WorldWideScience

Sample records for tar-contaminated freshwater sediments

  1. Abundance of dioxygenase genes similar to Ralstonia sp strain U2 nagAc is correlated with naphthalene concentrations in coal tar-contaminated freshwater sediments

    Energy Technology Data Exchange (ETDEWEB)

    Dionisi, H.M.; Chewning, C.S.; Morgan, K.H.; Menn, F.M.; Easter, J.P; Sayler, G.S. [University of Tennessee, Knoxville, TN (United States). Center for Environmental Biotechnology

    2004-07-01

    We designed a real-time PCR assay able to recognize dioxygenase large-subunit gene sequences with more than 90% similarity to the Ralstonia sp. strain U2 nagAc gene (nagAc-like gene sequences) in order to study the importance of organisms carrying these genes in the biodegradation of naphthalene. Sequencing of PCR products indicated that this real-time PCR assay was specific and able to detect a variety of nagAc-like gene sequences. One to 100 ng of contaminated-sediment total DNA in 25-{mu}l reaction mixtures produced an amplification efficiency of 0.97 without evident PCR inhibition. The assay was applied to surficial freshwater sediment samples obtained in or in close proximity to a coal tar-contaminated Superfund site. Naphthalene concentrations in the analyzed samples varied between 0.18 and 106 mg/kg of dry weight sediment. The assay for nagAc-like sequences indicated the presence of (4.1 {+-} 0.7) X 10{sup 3} to (2.9 {+-} 0.3) X 10{sup 5} copies of nagAc-like dioxygenase genes per mug of DNA extracted from sediment samples. These values corresponded to (1.2 {+-} 0.6) X 10{sup 5} to (5.4 {+-} 0.4) X 10{sup 7} copies of this target per g of dry weight sediment when losses of DNA during extraction were taken into account. There was a positive correlation between naphthalene concentrations and nagAc-like gene copies per microgram of DNA = 0.89) and per gram of dry weight sediment = 0.77). These results provide evidence of the ecological significance of organisms carrying nagAc-like genes in the biodegradation of naphthalene.

  2. Bench-scale demonstration of treatment technologies for contaminated sediments in Sydney Tar Ponds

    International Nuclear Information System (INIS)

    Volchek, K.; Velicogna, D.; Punt, M.; Wong, B.; Weimer, L.; Tsangaris, A.; Brown, C.E.

    2003-01-01

    A series of bench-scale tests were conducted to determine the capabilities of selected commercially available technologies for treating contaminated sediments from the South Pond of Sydney Tar Ponds. This study was conducted under the umbrella of a technology demonstration program aimed at evaluating technologies to be used in the remediation of such sediments. The following approach was proposed by SAIC Canada for the treatment of the sediments: (1) solvent extraction for the removal of organic contaminants, (2) acid/chelant leaching for the removal of inorganic contaminants such as heavy metals, and (3) plasma hearth process for the destruction of toxic streams resulting from the first two processes. Solvent extraction followed by plasma treatment proved effective for removing and destroying organic contaminants. The removal of metals did not achieve the expected results through leaching. An approach was proposed for treating those sediments based on the results of the study. The approach differed depending on the level of organic content. An assessment of associated process costs for both a pilot-scale field demonstration and a full-scale treatment was provided. 11 tabs., 4 figs

  3. Are PAHS the Right Metric for Assessing Toxicity Related to Oils, Tars, Creosote and Similar Contaminants in Sediments?

    Science.gov (United States)

    Oils, tars, and other non-aqueous phase hydrocarbon liquids (NAPLs) are common sources of contamination in aquatic sediments, and the toxicity of such contamination has generally been attributed to component chemicals, particularly PAHs. While there is no doubt PAHs can be toxic ...

  4. Remobilisation of uranium from contaminated freshwater sediments by bioturbation

    Energy Technology Data Exchange (ETDEWEB)

    Lagauzere, S.; Bonzom, J.M. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Saint-Paul-Lez-Durance (France). Lab. d' Ecotoxicologie des Radionucleides; Motelica-Heino, M. [Orleans Univ. (France). ISTO; Viollier, E. [Paris Diderot Univ., Paris (France). Inst. de Physique du Globe de Paris; Stora, G. [Aix-Marseille Univ., Marseille (France). Mediterranean Inst. of Oceanography (MIO)

    2014-07-01

    Benthic macro-invertebrate bioturbation can influence the remobilisation of uranium (U) initially associated with freshwater sediments, resulting in a high release of this pollutant through the overlying water column. Given the potential negative effects on aquatic biocenosis and the global ecological risk, it appears crucial to improve our current knowledge concerning the biogeochemical behaviour of U in sediments. The present study aimed to assess the biogeochemical modifications induced by Tubifex tubifex (Annelida, Clitellata, Tubificidae) bioturbation within the sediment in order to explain such a release of U. To reach this goal, U distribution between solid and solute phases of a reconstructed benthic system (i.e. in mesocosms) inhabited or not by T. tubifex worms was assessed in a 12-day laboratory experiment. Thanks notably to fine-resolution (mm-scale) measurements (e.g. ''diffusive equilibrium in thin-films'' DET gel probes for porewater, bioaccumulation in worms) of U and main chemical species (iron, sulfate, nitrate and nitrite), this work (i) confirmed that the removal of bottom sediment particles to the surface through the digestive tract of worms greatly favoured oxidative loss of U in the water column, and (ii) demonstrated that both U contamination and bioturbation of T. tubifex substantially influenced major microbial-driven biogeochemical reactions in sediments (e.g. stimulation of denitrification, sulfate reduction and iron dissolutive reduction). This study provides the first demonstration of biogeochemical modifications induced by bioturbation in freshwater U-contaminated sediments.

  5. A study of arsenic and chromium contamination in freshwater sediments

    International Nuclear Information System (INIS)

    Nazaratul Ashifa Abdullah Salim; Abdul Khalik Wood; Alias Mohd Yusof; Mohd Suhaimi Hamzah; Md Suhaimi Elias; Shamsiah Abdul Rahman

    2008-08-01

    Arsenic (As) is generally known for its toxicity while chromium (Cr) at the appropriate amount is an essential element to man and becomes quite toxic in excessive amount. Anthropogenic activities such as industrialization, agricultural and urbanization have led to the contamination of toxic elements into aquatic that finally end up in the sediment system. Environmental process like diagenetic process causes the toxic metals to migrate from the bedrock materials into the sediment surface and lastly into the water column. This process has been recognized to be the factor of arsenic contamination in well water in several countries such as Bangladesh, Taiwan, USA and Canada. A number of samples of freshwater sediments from identified rivers and lakes at Johor Bharu area had been analyzed to determine the concentration level of As and Cr using neutron activation analysis (NAA) technique. Certified Reference Material (CRM) namely BCSS-1 and IAEA Soil-7 were applied to provide good quality assurance control. The results obtained show that the concentrations of As in the rivers and lakes are 10-33 mg/g and 18-62 mg/g, respectively. The concentrations of Cr in the rivers range between 25 mg/g to125 mg/g, while in the lake sediments the concentrations range between 173 mg/g to 301 mg/g. The lakes sediments have higher As and Cr contents than the river sediment. The results of the As and Cr concentrations were then compared to the background value proposed by National Oceanic and Atmospheric Administration (NOAA), USA and interim freshwater sediment quality guidelines value established by Canadian Sediment Quality Guidelines for The Protection of Aquatic Life. (Author)

  6. Coal-tar-based sealcoated pavement: A major PAH source to urban stream sediments

    International Nuclear Information System (INIS)

    Witter, Amy E.; Nguyen, Minh H.; Baidar, Sunil; Sak, Peter B.

    2014-01-01

    We used land-use analysis, PAH concentrations and assemblages, and multivariate statistics to identify sediment PAH sources in a small (∼1303 km 2 ) urbanizing watershed located in South-Central, Pennsylvania, USA. A geographic information system (GIS) was employed to quantify land-use features that may serve as PAH sources. Urban PAH concentrations were three times higher than rural levels, and were significantly and highly correlated with combined residential/commercial/industrial land use. Principal components analysis (PCA) was used to group sediments with similar PAH assemblages, and correlation analysis compared PAH sediment assemblages to common PAH sources. The strongest correlations were observed between rural sediments (n = 7) and coke-oven emissions sources (r = 0.69–0.78, n = 5), and between urban sediments (n = 22) and coal-tar-based sealcoat dust (r = 0.94, n = 47) suggesting that coal-tar-based sealcoat is an important urban PAH source in this watershed linked to residential and commercial/industrial land use. -- Highlights: • Total PAH concentrations were measured at 35 sites along an urbanizing land-use gradient. • PAH concentrations increased with increasing urban land-use. • Urban land-use metrics were measured at three spatial scales using GIS. • PAH assemblages indicate coal-tar-based sealcoat is a major urban PAH source. • PAH assemblages indicate coke-oven emissions are an important rural PAH source. -- Coal-tar-based sealcoated pavement is a major PAH source to urban freshwater stream sediments in south-central Pennsylvania, USA

  7. Bioavailability and toxicity of metals from a contaminated sediment by acid mine drainage: linking exposure-response relationships of the freshwater bivalve Corbicula fluminea to contaminated sediment.

    Science.gov (United States)

    Sarmiento, Aguasanta M; Bonnail, Estefanía; Nieto, José Miguel; DelValls, Ángel

    2016-11-01

    Streams and rivers strongly affected by acid mine drainage (AMD) have legal vacuum in terms of assessing the water toxicity, since the use of conventional environmental quality biomarkers is not possible due to the absence of macroinvertebrate organisms. The Asian clam Corbicula fluminea has been widely used as a biomonitor of metal contamination by AMD in freshwater systems. However, these clams are considered an invasive species in Spain and the transplantation in the field study is not allowed by the Environmental Protection Agency. To evaluate the use of the freshwater bivalve C. fluminea as a potential biomonitor for sediments contaminated by AMD, the metal bioavailability and toxicity were investigated in laboratory by exposure of clams to polluted sediments for 14 days. The studied sediments were classified as slightly contaminated with As, Cr, and Ni; moderately contaminated with Co; considerably contaminated with Pb; and heavily contaminated with Cd, Zn, and specially Cu, being reported as very toxic to Microtox. On the fourth day of the exposure, the clams exhibited an increase in concentration of Ga, Ba, Sb, and Bi (more than 100 %), followed by Co, Ni, and Pb (more than 60 %). After the fourth day, a decrease in concentration was observed for almost all metals studied except Ni. An allometric function was used to determine the relationship between the increases in metal concentration in soft tissue and the increasing bioavailable metal concentrations in sediments.

  8. Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

    International Nuclear Information System (INIS)

    Hoess, S.; Ahlf, W.; Fahnenstich, C.; Gilberg, D.; Hollert, H.; Melbye, K.; Meller, M.; Hammers-Wirtz, M.; Heininger, P.; Neumann-Hensel, H.; Ottermanns, R.; Ratte, H.-T.

    2010-01-01

    Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

  9. Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

    Energy Technology Data Exchange (ETDEWEB)

    Hoess, S., E-mail: hoess@ecossa.d [Ecossa, Giselastr. 6, 82319 Starnberg (Germany); Institute of Biodiversity - Network (IBN), Dreikronengasse 2, 93047 Regensburg (Germany); Ahlf, W., E-mail: ahlf@tu-harburg.d [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Fahnenstich, C. [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Gilberg, D., E-mail: d-gilberg@ect.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hollert, H., E-mail: henner.hollert@bio5.rwth-aachen.d [Department of Ecosystem Analysis, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Melbye, K. [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Meller, M., E-mail: m-meller@ecotox-consult.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hammers-Wirtz, M., E-mail: hammers-wirtz@gaiac.rwth-aachen.d [Research Institute for Ecosystem Analysis and Assessment (gaiac), RWTH Aachen University, Worringerweg 1, 52056 Aachen (Germany); Heininger, P., E-mail: heininger@bafg.d [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56070 Koblenz (Germany); Neumann-Hensel, H., E-mail: hensel@fintelmann-meyer.d [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Ottermanns, R., E-mail: ottermanns@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Ratte, H.-T., E-mail: toni.ratte@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany)

    2010-09-15

    Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

  10. Tributyltin-resistant bacteria from estuarine and freshwater sediments.

    Science.gov (United States)

    Wuertz, S; Miller, C E; Pfister, R M; Cooney, J J

    1991-01-01

    Resistance to tributyltin (TBT) was examined in populations from TBT-polluted sediments and nonpolluted sediments from an estuary and from fresh water as well as in pure cultures isolated from those sediments. The 50% effective concentrations (EC50s) for populations were higher at a TBT-polluted freshwater site than at a site without TBT, suggesting that TBT selected for a TBT-resistant population. In contrast, EC50s were significantly lower for populations from a TBT-contaminated estuarine site than for those from a site without TBT, suggesting that other factors in addition to TBT determine whether populations become resistant. EC50s for populations from TBT-contaminated freshwater sediments were nearly 30 times higher than those for populations from TBT-contaminated estuarine sediments. We defined a TBT-resistant bacterium as one which grows on trypticase soy agar containing 8.4 microM TBT, a concentration which prevented the growth of 90% of the culturable bacteria from these sediments. The toxicity of TBT in laboratory media was influenced markedly by the composition of the medium and whether it was liquid or solid. Ten TBT-resistant isolates from estuarine sediments and 19 from freshwater sediments were identified to the genus level. Two isolates, each a Bacillus sp., may be the first gram-positive bacteria isolated from fresh water in the presence of a high concentration of TBT. There was a high incidence of resistance to heavy metals: metal resistance indices were 0.76 for estuarine isolates and 0.68 for freshwater isolates.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1746939

  11. Nontarget analysis of polar contaminants in freshwater sediments influenced by pharmaceutical industry using ultra-high-pressure liquid chromatography-quadrupole time-of-flight mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Terzic, Senka, E-mail: terzic@irb.h [Division of Marine and Environmental Research, Rudjer Boskovic Institute, 10000 Zagreb (Croatia); Ahel, Marijan [Division of Marine and Environmental Research, Rudjer Boskovic Institute, 10000 Zagreb (Croatia)

    2011-02-15

    A comprehensive analytical procedure for a reliable identification of nontarget polar contaminants in aquatic sediments was developed, based on the application of ultra-high-pressure liquid chromatography (UHPLC) coupled to hybrid quadrupole time-of-flight mass spectrometry (QTOFMS). The procedure was applied for the analysis of freshwater sediment that was highly impacted by wastewater discharges from the pharmaceutical industry. A number of different contaminants were successfully identified owing to the high mass accuracy of the QTOFMS system, used in combination with high chromatographic resolution of UHPLC. The major compounds, identified in investigated sediment, included a series of polypropylene glycols (n = 3-16), alkylbenzene sulfonate and benzalkonium surfactants as well as a number of various pharmaceuticals (chlorthalidone, warfarin, terbinafine, torsemide, zolpidem and macrolide antibiotics). The particular advantage of the applied technique is its capability to detect less known pharmaceutical intermediates and/or transformation products, which have not been previously reported in freshwater sediments. - Research highlights: UHPLC-QTOFMS coupling was applied for nontarget analysis of polar contaminants. Wide spectrum of polar contaminants was identified in polluted sediments. Pharmaceuticals and their intermediates were present in high concentrations. - Comprehensive analysis of freshwater sediments by UPLC/QTOF indicated importance of pharmaceutically-derived polar contaminants.

  12. Nontarget analysis of polar contaminants in freshwater sediments influenced by pharmaceutical industry using ultra-high-pressure liquid chromatography-quadrupole time-of-flight mass spectrometry

    International Nuclear Information System (INIS)

    Terzic, Senka; Ahel, Marijan

    2011-01-01

    A comprehensive analytical procedure for a reliable identification of nontarget polar contaminants in aquatic sediments was developed, based on the application of ultra-high-pressure liquid chromatography (UHPLC) coupled to hybrid quadrupole time-of-flight mass spectrometry (QTOFMS). The procedure was applied for the analysis of freshwater sediment that was highly impacted by wastewater discharges from the pharmaceutical industry. A number of different contaminants were successfully identified owing to the high mass accuracy of the QTOFMS system, used in combination with high chromatographic resolution of UHPLC. The major compounds, identified in investigated sediment, included a series of polypropylene glycols (n = 3-16), alkylbenzene sulfonate and benzalkonium surfactants as well as a number of various pharmaceuticals (chlorthalidone, warfarin, terbinafine, torsemide, zolpidem and macrolide antibiotics). The particular advantage of the applied technique is its capability to detect less known pharmaceutical intermediates and/or transformation products, which have not been previously reported in freshwater sediments. - Research highlights: → UHPLC-QTOFMS coupling was applied for nontarget analysis of polar contaminants. → Wide spectrum of polar contaminants was identified in polluted sediments. → Pharmaceuticals and their intermediates were present in high concentrations. - Comprehensive analysis of freshwater sediments by UPLC/QTOF indicated importance of pharmaceutically-derived polar contaminants.

  13. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

    International Nuclear Information System (INIS)

    Bryer, Pamela J.; Scoggins, Mateo; McClintock, Nancy L.

    2010-01-01

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, and 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments. - Coal-tar pavement sealants degrade stream invertebrate communities.

  14. Biological processes influencing contaminant release from sediments

    International Nuclear Information System (INIS)

    Reible, D.D.

    1996-01-01

    The influence of biological processes, including bioturbation, on the mobility of contaminants in freshwater sediments is described. Effective mass coefficients are estimated for tubificid oligochaetes as a function of worm behavior and biomass density. The mass transfer coefficients were observed to be inversely proportional to water oxygen content and proportional to the square root of biomass density. The sediment reworking and contaminant release are contrasted with those of freshwater amphipods. The implications of these and other biological processes for contaminant release and i n-situ remediation of soils and sediments are summarized. 4 figs., 1 tab

  15. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Bryer, P.J.; Scoggins, M.; McClintock, N.L. [Lamar University, Beaumont, TX (United States). Dept. of Biology

    2010-05-15

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments.

  16. Mineralization of PAHs in coal-tar impacted aquifer sediments and associated microbial community structure investigated with FISH

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, S W; Ong, S K; Moorman, T B [Iowa State University, Ames, IA (USA)

    2007-11-15

    The microbial community structure and mineralization of polycyclic aromatic hydrocarbons (PAHs) in a coal-tar contaminated aquifer were investigated spatially using fluorescence in situ hybridization (FISH) and in laboratory-scale incubations of the aquifer sediments. DAPI-detected microbial populations in the contaminated sediments were three orders of magnitude greater than nearby uncontaminated sediments, suggesting growth on coal-tar constituents in situ. Actinobacteria, {beta}- and {gamma}-Proteobacteria, and Flavobacteria dominated the in situ aerobic (> 1 mg l{sup -1} dissolved oxygen) microbial community, whereas sulfate-reducing bacteria comprised 37% of the microbial community in the sulfidogenic region of the aquifer. Rapid mineralization of naphthalene and phenanthrene were observed in aerobic laboratory microcosms and resulted in significant enrichment of {beta}- and {gamma}-Proteobacteria potentially explaining their elevated presence in situ. Nitrate- and sulfate-limited mineralization of naphthalene in laboratory microcosms occurred to a small degree in aquifer sediments from locations where groundwater chemistry indicated nitrate- and sulfate-reduction, respectively. The results of this study suggest that FISH may be a useful tool for providing a link between laboratory microcosms and groundwater measurements made in situ necessary to better demonstrate the potential for natural attenuation at complex PAH contaminated sites.

  17. Bioremediation potential of coal-tar-oil-contaminated soil

    International Nuclear Information System (INIS)

    Lajoie, C.A.

    1991-01-01

    The bioremediation of coal tar oil contaminated soil was investigated in 90 day laboratory simulation experiments. The effect of soil moisture, humic acid amendment, and coal tar oil concentration on the rate of disappearance of individual coal tar oil constituents (PAHs and related compounds) was determined by methylene chloride extraction and gas chromatography. Mass balance experiments determined the fate of both the individual 14 C-labeled PAHs phenanthrene, pyrene, and benzo(a)pyrene, and the total coal tar oil carbon. Mineralization, volatilization, incorporation into microbial biomass, disappearance of individual coal tar oil constitutents, and the distribution of residual 14 C-activity in different soil fractions were measured. The rate of disappearance of coal tar oil constituents increased with increasing soil moisture over the experimental range. Humic acid amendment initially enhanced the rate of disappearance, but decreased the extent of disappearance. The amount of contamination removed decreased at higher coal tar oil concentrations. The practical limit for biodegradation in the system tested appeared to be between 1.0 and 2.5% coal tar oil. Mineralization accounted for 40 to 50% of the applied coal tar oil. Volatilization was a minor pathway of disappearance

  18. Ultrasound-assisted extraction method for the simultaneous determination of emerging contaminants in freshwater sediments.

    Science.gov (United States)

    de Sousa, Diana Nara Ribeiro; Grosseli, Guilherme Martins; Mozeto, Antonio Aparecido; Carneiro, Renato Lajarim; Fadini, Pedro Sergio

    2015-10-01

    Sediments are the fate of several emerging organic contaminants, such as pharmaceuticals, personal care products and hormones, and therefore an important subject in environmental monitoring studies. In the present work, a simple and sensitive method was developed, validated and applied for the simultaneous extraction of atenolol, caffeine, carbamazepine, diclofenac, ibuprofen, naproxen, propranolol, triclosan, estrone, 17-β-estradiol and 17-α-ethinylestradiol using ultrasound-assisted extraction from freshwater sediment samples followed by solid-phase extraction clean-up and liquid chromatography with tandem mass spectrometry detection. The solvent type and extraction pH were evaluated to obtain the highest recoveries of the compounds. The best method shows absolute recoveries between 54.0 and 94.4% at 50 ng/g concentration. The method exhibits good precision with relative standard deviation ranging from 1.0-16%. The detection and quantification limits ranged from 0.006-0.067 and 0.016-0.336 ng/g, respectively. The developed method was successfully applied to freshwater sediment samples collected from different sites in Jundiaí River basin of São Paulo State, Brazil. The compounds atenolol, caffeine, propranolol and triclosan were detected in all the sampling sites with concentrations of 13.8, 41.0, 28.5 and 176 ng/g, respectively. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Coal-tar based pavement sealant toxicity to freshwater macroinvertebrates.

    Science.gov (United States)

    Bryer, Pamela J; Scoggins, Mateo; McClintock, Nancy L

    2010-05-01

    Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P pavement sealants contain bioavailable PAHs that may harm aquatic environments. Copyright 2009 Elsevier Ltd. All rights reserved.

  20. Tributyltin-resistant bacteria from estuarine and freshwater sediments.

    OpenAIRE

    Wuertz, S; Miller, C E; Pfister, R M; Cooney, J J

    1991-01-01

    Resistance to tributyltin (TBT) was examined in populations from TBT-polluted sediments and nonpolluted sediments from an estuary and from fresh water as well as in pure cultures isolated from those sediments. The 50% effective concentrations (EC50s) for populations were higher at a TBT-polluted freshwater site than at a site without TBT, suggesting that TBT selected for a TBT-resistant population. In contrast, EC50s were significantly lower for populations from a TBT-contaminated estuarine s...

  1. DNA-SIP identifies sulfate-reducing Clostridia as important toluene degraders in tar-oil-contaminated aquifer sediment

    Energy Technology Data Exchange (ETDEWEB)

    Winderl, C.; Penning, H.; von Netzer, F.; Meckenstock, R.U.; Lueders, T. [Helmholtz Zentrum Munchen, Neuherberg (Germany)

    2010-10-15

    Global groundwater resources are constantly challenged by a multitude of contaminants such as aromatic hydrocarbons. Especially in anaerobic habitats, a large diversity of unrecognized microbial populations may be responsible for their degradation. Still, our present understanding of the respective microbiota and their ecophysiology is almost exclusively based on a small number of cultured organisms, mostly within the Proteobacteria. Here, by DNA-based stable isotope probing (SIP), we directly identified the most active sulfate-reducing toluene degraders in a diverse sedimentary microbial community originating from a tar-oil-contaminated aquifer at a former coal gasification plant. On incubation of fresh sediments with {sup 13}C{sub 7}-toluene, the production of both sulfide and (CS{sub 2}){sup 13}CO{sub 2} was clearly coupled to the {sup 13}Clabeling of DNA of microbes related to Desulfosporosinus spp. within the Peptococcaceae (Clostridia). The screening of labeled DNA fractions also suggested a novel benzylsuccinate synthase alpha-subunit (bssA) sequence type previously only detected in the environment to be tentatively affiliated with these degraders. However, carbon flow from the contaminant into degrader DNA was only similar to 50%, pointing toward high ratios of heterotrophic CS{sub 2}-fixation during assimilation of acetyl-CoA originating from the contaminant by these degraders. These findings demonstrate that the importance of non-proteobacterial populations in anaerobic aromatics degradation, as well as their specific ecophysiology in the subsurface may still be largely ungrasped.

  2. In situ solidification/stabilization pilot study for the treatment of coal tar contaminated soils and river sediments

    International Nuclear Information System (INIS)

    Lawson, M.A.; Venn, J.G.; Pugh, L.B.; Vallis, T.

    1996-01-01

    Coal tar contamination was encountered at a former coal gasification site in soils below the groundwater table, and in the sediments of the adjacent river. Ex situ remediation techniques at this site would be costly because of the need to dewater the impacted media. In situ solidification/stabilization was tested to evaluate its effectiveness. Treatability testing was performed to evaluate a Portland cement/fly ash binder system with added stabilizing agents. Results were sufficiently promising to warrant pilot testing. Grout containing Portland cement, fly ash, organically modified clay, and granular activated carbon was pilot tested at the site. Test specimens were collected and tested to evaluate durability, compressive strength, and permeability. The samples were extracted by several methods and analyzed to measure the leachable concentrations of organic compounds and metals. Results indicated acceptable physical characteristics. Leachable concentrations of most polynuclear aromatic compounds were decreased

  3. Toxicity and bioaccumulation of sediment-associated contaminants using freshwater invertebrates: A review of methods and applications

    Science.gov (United States)

    Ingersoll, C.G.; Ankley, G.T.; Benoit, D.A.; Brunson, E.L.; Burton, G.A.; Dwyer, F.J.; Hoke, R.A.; Landrum, P.F.; Norberg-King, T. J.; Winger, P.V.

    1995-01-01

    This paper reviews recent developments in methods for evaluating the toxicity and bioaccumulation of contaminants associated with freshwater sediments and summarizes example case studies demonstrating the application of these methods. Over the past decade, research has emphasized development of more specific testing procedures for conducting 10-d toxicity tests with the amphipod Hyalella azteca and the midge Chironomus tentans. Toxicity endpoints measured in these tests are survival for H. azteca and survival and growth for C. tentans. Guidance has also been developed for conducting 28-d bioaccumulation tests with the oligochaete Lumbriculus variegatus, including determination of bioaccumulation kinetics for different compound classes. These methods have been applied to a variety of sediments to address issues ranging from site assessments to bioavailability of organic and inorganic contaminants using field-collected and laboratory-spiked samples. Survival and growth of controls routinely meet or exceed test acceptability criteria. Results of laboratory bioaccumulation studies with L. variegatus have been confirmed with comparisons to residues (PCBs, PAHs, DDT) present from synoptically collected field populations of oligochaetes. Additional method development is currently underway to develop chronic toxicity tests and to provide additional data-confirming responses observed in laboratory sediment tests with natural benthic populations.

  4. Release of polyaromatic hydrocarbons from coal tar contaminated soils

    International Nuclear Information System (INIS)

    Priddy, N.D.; Lee, L.S.

    1996-01-01

    A variety of process wastes generated from manufactured gas production (MGP) have contaminated soils and groundwater at production and disposal sites. Coal tar, consisting of a complex mixture of hydrocarbons present as a nonaqueous phase liquid, makes up a large portion of MGP wastes. Of the compounds in coal tar, polyaromatic hydrocarbons (PAHs) are the major constituents of environmental concern due to their potential mutagenic and carcinogenic hazards. Characterization of the release of PAHs from the waste-soil matrix is essential to quantifying long-term environmental impacts in soils and groundwater. Currently, conservative estimates for the release of PAHs to the groundwater are made assuming equilibrium conditions and using relationships derived from artificially contaminated soils. Preliminary work suggests that aged coal tar contaminated soils have much lower rates of desorption and a greater affinity for retaining organic contaminants. To obtain better estimates of desorption rates, the release of PAHs from a coal tar soil was investigated using a flow-interruption, miscible displacement technique. Methanol/water solutions were employed to enhance PAH concentrations above limits of detection. For each methanol/water solution employed, a series of flow interrupts of varying times was invoked. Release rates from each methanol/water solution were estimated from the increase in concentration with duration of flow interruption. Aqueous-phase release rates were then estimated by extrapolation using a log-linear cosolvency model

  5. Contaminants in the Greenland terrestrial and freshwater environment. National assessment

    International Nuclear Information System (INIS)

    Riget, F.; Aastrup, P.; Dietz, R.

    1997-01-01

    The present report reviews the available information on heavy metals, persistent organic pollutants and radioactivity in the Greenland freshwater and terrestrial environments. Levels in lake sediments, soil, humus and organisms are presented, spatial and temporal trends are discussed and where possible also biological effects. Many of the contaminants that occur in the Greenland environment originate from distant sources outside of the region, and are transported to the Arctic via three major pathways - atmospheric, terrestrial/freshwater and marine. The main sources of pollution in Greenland is considered to be the industrialization of Eurasia. Pollutants are mainly. The organochlorine levels in Greenland char are typically in the low range compared to values reported from Canada. The Greenland sediment samples showed all organochlorine values below the detection limits of 0.1 μg/kg dry weight, thus being among the lowest contaminated sediments within the Arctic. The total content of PAH in the Greenland sediment samples ranged between 78-635 μ3 g/kg dry wight, with a geometric mean of 178 μg/kg, comparable to or lower than reported values from other arctic countries. The lowest concentrations of anthropogenic radionuclides in the Greenland terrestrial and freshwater environment are found in the northern parts of Greenland and the highest in the south western parts. The main source of anthropogenic radioactivity is nuclear weapons testing in the atmosphere and the fallout from this activity is closely related to the amounts of precipitation. The predominant foodchain in the Arctic with regard to transport of radiocaesium to man is: Lichen-reindeer-man. Although the doses from the terrestrial foodchain are 20 times higher than those received from the marine foodchain, they are not considered to be of any relevance for the human health in Greenland. 4 appendices contain experimental results. (EG)

  6. Cable Bacteria in Freshwater Sediments

    DEFF Research Database (Denmark)

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus

    2015-01-01

    In marine sediments cathodic oxygen reduction at the sediment surface can be coupled to anodic sulfide oxidation in deeper anoxic layers through electrical currents mediated by filamentous, multicellular bacteria of the Desulfobulbaceae family, the so-called cable bacteria. Until now, cable...... bacteria have only been reported from marine environments. In this study, we demonstrate that cable bacteria also occur in freshwater sediments. In a first step, homogenized sediment collected from the freshwater stream Giber Å, Denmark, was incubated in the laboratory. After 2 weeks, pH signatures...... marine cable bacteria, with the genus Desulfobulbus as the closest cultured lineage. The results of the present study indicate that electric currents mediated by cable bacteria could be important for the biogeochemistry in many more environments than anticipated thus far and suggest a common evolutionary...

  7. Coal-tar-based pavement sealcoat and PAHs: implications for the environment, human health, and stormwater management.

    Science.gov (United States)

    Mahler, Barbara J; Metre, Peter C Van; Crane, Judy L; Watts, Alison W; Scoggins, Mateo; Williams, E Spencer

    2012-03-20

    Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20-35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments-including stormwater runoff, lake sediment, soil, house dust, and most recently, air-contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them.

  8. Coal-tar-based pavement sealcoat and PAHs: implications for the environment, human health, and stormwater management

    Science.gov (United States)

    Mahler, Barbara J.; Van Metre, Peter C.; Crane, Judy L.; Watts, Alison W.; Scoggins, Mateo; Williams, E. Spencer

    2012-01-01

    Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20-35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments—including stormwater runoff, lake sediment, soil, house dust, and most recently, air—contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them.

  9. Thermal remediation of tar-contaminated soil and oil-contaminated gravel

    International Nuclear Information System (INIS)

    Anthony, E.J.; Wang, J.

    2005-01-01

    High temperature treatments are commonly considered for the decontamination of soil as they have the advantages of reliability, high capacity, and effective destruction of hazardous materials with reduced long-term liability. This paper examined the remediation of soil contaminated by coal tar as well as gravel contaminated by oil. Pilot plant studies were conducted using 2 representative incineration technologies: rotary kiln and fluidized bed. The coal tar contaminated soil had accumulated over a few decades at a calcination plant in western Canada. The soil was sticky and could not be handled by conventional feeding and combustion systems. Crushed lignite was mixed with the soil as an auxiliary fuel and to reduce stickiness. A pilot plant furnace was used to evaluate the potential of decontamination in a rotary calciner. An analysis of both a modelling study and the test results showed that complete decontamination could be achieved in the targeted calciner. The results suggested that energy recovery was also possible, which could in turn make the remediation process more cost-effective. Decontamination of oil-contaminated gravel was conducted with a pilot plant fluidized bed combustor to study the feasibility of using incineration technology in the remediation of gravel and debris contaminated by oil spills. Results indicated that the gravel was decontaminated with acceptable emission performance. It was concluded that the study will be valuable to the application of commercial incineration processes for the remediation of polluted soils. It was observed that the weathering of the oiled gravel lowered the rate of decontamination. A small amount of salt water resulted in lowered decontamination rates, which may be an important factor for situations involving the remediation of shoreline gravel contaminated by oil. 24 refs., 6 tabs., 7 figs

  10. Studies estimating the dermal bioavailability of polynuclear aromatic hydrocarbons from manufactured plant tar-contaminated soils

    International Nuclear Information System (INIS)

    Roy, T.A.; Krueger, A.J.; Taylor, B.B.; Mauro, D.M.; Goldstein, L.S.

    1998-01-01

    In vitro percutaneous absorption studies were performed with contaminated soils or organic extracts of contaminated soils collected at manufactured gas plant (MGP) sites. The MGP tar contaminated soils were found to contain a group of targeted polynuclear aromatic hydrocarbons (PAH) at levels ranging from 10 to 2400 mg/kg. The soil extracts contained target PAH at levels ranging from 12 000 - 34 000 mg/kg. Dermal penetration rates of target PAH from the MGP tar-contaminated soils/soil extracts were determined experimentally through human skin using 3 H-benzo(a)pyrene (BaP) as a surrogate. Results from three MGP sites showed reductions of 2-3 orders of magnitude in PAH absorption through human skin from the most contaminated soils in comparison to the soil extracts. Reduction in PAH penetration can be attributed to PAH concentration and (soil) matrix properties. PAH dermal flux values are used to determine site-specific dermally absorbed dose (DAD) and chronic daily intake (CDI) which are essential terms required to estimate risk associated with human exposure to MGP tar and MGP tar-contaminated soils. 21 refs., 4 figs., 3 tabs

  11. Looking at biological community level to improve ecotoxicological assessment of freshwater sediments: report on a first French-Swiss workshop.

    Science.gov (United States)

    Pesce, Stéphane; Perceval, Olivier; Bonnineau, Chloé; Casado-Martinez, Carmen; Dabrin, Aymeric; Lyautey, Emilie; Naffrechoux, Emmanuel; Ferrari, Benoit J D

    2018-01-01

    The first French-Swiss workshop on ecotoxicology of freshwater sediment communities was co-organized by the French Research Institute of Science and Technology for Environment and Agriculture (Irstea) and the Swiss Centre for Applied Ecotoxicology (Ecotox Centre EAWAG-EPFL) in Villié-Morgon (Beaujolais Region, France) on April 27-28, 2017. The workshop brought together scientists working in different fields of expertise (ecotoxicologists, ecologists, environmental chemists…), environmental stakeholder groups and managers, as well as economic players (start-ups and consultancies) to better connect research needs of potential end-users with research outputs. The objectives of this workshop were (i) to establish the state of the art of research in the characterization of sediment contamination and in the evaluation of the effects on sediment-associated biological communities and ecosystem functioning and (ii) to give an overview of the French and Swiss regulations dealing with the assessment of contaminated sediments in freshwater ecosystems. The ultimate goal was to collectively identify research needs and knowledge gaps, as well as to highlight ways to improve the ecotoxicological assessment of sediments in freshwater environments by further considering the structure and functions of associated microbial and invertebrate communities.

  12. Coal-tar-based sealcoated pavement: a major PAH source to urban stream sediments.

    Science.gov (United States)

    Witter, Amy E; Nguyen, Minh H; Baidar, Sunil; Sak, Peter B

    2014-02-01

    We used land-use analysis, PAH concentrations and assemblages, and multivariate statistics to identify sediment PAH sources in a small (~1303 km(2)) urbanizing watershed located in South-Central, Pennsylvania, USA. A geographic information system (GIS) was employed to quantify land-use features that may serve as PAH sources. Urban PAH concentrations were three times higher than rural levels, and were significantly and highly correlated with combined residential/commercial/industrial land use. Principal components analysis (PCA) was used to group sediments with similar PAH assemblages, and correlation analysis compared PAH sediment assemblages to common PAH sources. The strongest correlations were observed between rural sediments (n = 7) and coke-oven emissions sources (r = 0.69-0.78, n = 5), and between urban sediments (n = 22) and coal-tar-based sealcoat dust (r = 0.94, n = 47) suggesting that coal-tar-based sealcoat is an important urban PAH source in this watershed linked to residential and commercial/industrial land use. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Sorption kinetics of TNT and RDX in anaerobic freshwater and marine sediments: Batch studies.

    Science.gov (United States)

    Ariyarathna, Thivanka; Vlahos, Penny; Tobias, Craig; Smith, Richard

    2016-01-01

    Examination of the partitioning of explosives onto sediment in marine environments is critical to predict the toxicological impacts of worldwide explosive-contaminated sites adjacent to estuaries, wetlands, and the coastal ocean. Marine sediments have been identified as sites of enhanced munitions removal, yet most studies addressing these interactions focus on soils and freshwater sediments. The present study measured the kinetics of 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) sorption onto 2 marine sediments of varying grain sizes (silt vs sand) and organic carbon (OC) content. Abiotic sediment sorption tests were performed at 23 °C, 15 °C, and 4 °C by spiking TNT and RDX solutions directly into anaerobic sediment slurries. Marine sediments showed significantly higher compound uptake rates (0.30-0.80 h(-1) ) than freshwater silt (0.0046-0.0065 h(-1) ) for both compounds, probably because of lower compound solubilities and a higher pH in marine systems. Equilibrium partition constants are on the same order of magnitude for marine silt (1.1-2.0 L kg(-1) sediment) and freshwater silt (1.4-3.1 L kg(-1) sediment) but lower for marine sand (0.72-0.92 L kg(-1) sediment). Total organic carbon content in marine sediments varied linearly with equilibrium partition constants for TNT and was moderately linear for RDX. Uptake rates and equilibrium constants of explosives are inversely correlated to temperature regardless of sediment type because of kinetic barriers associated with low temperatures. © 2015 SETAC.

  14. Direct and indirect effects of copper-contaminated sediments on the functions of model freshwater ecosystems.

    Science.gov (United States)

    Gardham, Stephanie; Chariton, Anthony A; Hose, Grant C

    2015-01-01

    Copper is acutely toxic to, and directly affects, primary producers and decomposers, which are key players in essential processes such as the nutrient cycle in freshwater ecosystems. Even though the indirect effects of metals (for example effects due to changes in species interactions) may be more common than direct effects, little is known about the indirect effects of copper on primary producers and decomposers. The effects of copper on phytoplankton, macrophytes, periphyton and organic matter decomposition in an outdoor lentic mesocosm facility were assessed, and links between the responses examined. Copper directly decreased macrophyte growth, subsurface organic matter decomposition, and the potential for high phytoplankton Chlorophyll a concentrations. However, periphyton cover and organic matter decomposition on the surface of the sediment were stimulated by the presence of copper. These latter responses were attributed to indirect effects, due to a reduction in grazing pressure from snails, particularly Physa acuta, in the higher copper-contaminated mesocosms. This permitted the growth of periphyton and other heterotrophs, ultimately increasing decomposition at the sediment surface. The present study demonstrates the pronounced influence indirect effects may have on ecological function, findings that may not be observed in traditional laboratory studies (which utilize single species or simplistic communities).

  15. Assessment of ground-water contamination by coal-tar derivatives, St. Louis Park area, Minnesota

    Science.gov (United States)

    Hult, M.F.

    1984-01-01

    Operation of a coal-tar distillation and wood-preserving facility in St. Louis Park, Minnesota, during 1918-72 contaminated ground water with coal-tar derivatives and inorganic chemicals. Coal-tar derivatives entered the groundwater system through three major paths: (1) Spills and drippings that percolated to the water table, (2) surface runoff and plant process water that was discharged to wetlands south of the former plant site, and (3) movement of coal tar directly into bedrock aquifers through a multiaquifer well on the site.

  16. A comparison of the response of Simocephalus mixtus (Cladocera) and Daphnia magna to contaminated freshwater sediments.

    Science.gov (United States)

    Martínez-Jerónimo, Fernando; Cruz-Cisneros, Jade Lizette; García-Hernández, Leonardo

    2008-09-01

    The southeast region of Mexico is characterized by intensive oil industry activities carried out by the national public enterprise Petróleos Mexicanos (PEMEX). The freshwater lagoon "El Limón", located in the municipality of Macuspana, state of Tabasco, Mexico, has received over 40 years discharges of untreated waste waters from the Petrochemical Complex "Ciudad PEMEX", located on the border of the lagoon. To assess the toxicity of the sediments and, hence, to obtain information on the biological effects of these contaminating discharges, the cladoceran Simocephalus mixtus was used as a test organism in acute (48h) and chronic (12d) toxicity assays. For comparison purposes, bioassays were also conducted with the reference cladoceran Daphnia magna. The sediments of this lagoon contain important amounts of metals and hydrocarbons that have been accumulated over time; however, the acute tests only registered reduced lethal effects on the test organisms (maxima of 10% and 17% mortality for D. magna and S. mixtus, respectively). This may be due to low bioavailability of the pollutants present in the sediments. On the other hand, partial or total inhibition and delay in the start of reproduction, reduction in clutch sizes, reduced survival, as well as reduction in the size of adults and offspring were recorded in the chronic assays. The most evident chronic effects were found in S. mixtus; in this species, reproduction was inhibited up to 72%, whereas D. magna was only affected by 24%. We determined that S. mixtus is a more sensitive test organism than D. magna to assess whole-sediment toxicity in tropical environments, and that chronic exposure bioassays are required for an integrated sediment evaluation. The sediments from "El Limón" lagoon induced chronic intoxication responses and, therefore, remediation measures are urgently needed to recover environmental conditions suitable for the development of its aquatic biota.

  17. Concentration of arsenic in water, sediments and fish species from naturally contaminated rivers.

    Science.gov (United States)

    Rosso, Juan José; Schenone, Nahuel F; Pérez Carrera, Alejo; Fernández Cirelli, Alicia

    2013-04-01

    Arsenic (As) may occur in surface freshwater ecosystems as a consequence of both natural contamination and anthropogenic activities. In this paper, As concentrations in muscle samples of 10 fish species, sediments and surface water from three naturally contaminated rivers in a central region of Argentina are reported. The study area is one of the largest regions in the world with high As concentrations in groundwater. However, information of As in freshwater ecosystems and associated biota is scarce. An extensive spatial variability of As concentrations in water and sediments of sampled ecosystems was observed. Geochemical indices indicated that sediments ranged from mostly unpolluted to strongly polluted. The concentration of As in sediments averaged 6.58 μg/g ranging from 0.23 to 59.53 μg/g. Arsenic in sediments barely followed (r = 0.361; p = 0.118) the level of contamination of water. All rivers showed high concentrations of As in surface waters, ranging from 55 to 195 μg/L. The average concentration of As in fish was 1.76 μg/g. The level of contamination with As differed significantly between species. Moreover, the level of bioaccumulation of As in fish species related to the concentration of As in water and sediments also differed between species. Whilst some fish species seemed to be able to regulate the uptake of this metalloid, the concentration of As in the large catfish Rhamdia quelen mostly followed the concentration of As in abiotic compartments. The erratic pattern of As concentrations in fish and sediments regardless of the invariable high levels in surface waters suggests the existence of complex biogeochemical processes behind the distribution patterns of As in these naturally contaminated ecosystems.

  18. Avoidance of polycyclic aromatic hydrocarbon-contaminated sediments by the freshwater invertebrates Gammarus pulex and Asellus aquaticus

    NARCIS (Netherlands)

    Lange, de H.J.; Sperber, V.; Peeters, E.T.H.M.

    2006-01-01

    Contamination of sediments is a serious problem in most industrialized areas. Sediments are often contaminated with trace metals and organic contaminants like polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Bioassays are often used to determine the effect of

  19. Investigation of changes in {delta}{sup 13}C of PAHs during phytoremediation of coal tar-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Mick Cooper; Cheng-Gong Sun; Margaret Smith; Harry Duncan; Colin Snape [University of Nottingham, Nottingham (United Kingdom). School of Chemical Environmental and Mining Engineering

    2007-07-01

    It has been shown that phytoremediation of polyaromatic hydrocarbon (PAH) contaminated land is a useful, low cost, low maintenance method of cleaning up land at former gas and coking works. However, PAH degradation in the soil and sediment is slow, but PAHs may be degraded through properly stimulated soil micro-organisms. Here we describe a laboratory trial, employing the clover Trifolium pretense (L.)(TP), which was grown in samples of soil contaminated by fresh coal tar, and in soil heavily contaminated by PAHs, obtained from a former coking works. As the latter substrate was 'naturally' contaminated, it contained both pure PAHs and their derivatives, and was thus considered fully 'weathered', and contained recalcitrant PAH species. Conventional analytical techniques (for example, GC-MS) generally provide little information on the source of pollutants such as PAHs. Previous work has established, however, that significant differences existed in the {sup 13}C/{sup 12}C isotopic ratios between PAHs from various sources. Source apportionment of PAH contamination by stable isotope analysis is a powerful technique, but one which assumes that isotopic fractionation is not a significant factor in aged or bioaltered matrices. Phytoremediation trials described here have been utilised in order to determine whether or not any such fractionation of {sup 13}C occurs during the process. Although PAH distributions can be markedly altered by biodegradation, it has been demonstrated that, for low temperature coal tar, the carbon stable isotopic values of the parent PAHs remain fairly constant. 22 refs., 2 figs., 5 tabs.

  20. Anthropogenic pollutants affect ecosystem services of freshwater sediments. The need for a 'triad plus x' approach

    Energy Technology Data Exchange (ETDEWEB)

    Gerbersdorf, Sabine Ulrike; Wieprecht, Silke [Stuttgart Univ. (Germany). Dept. of Hydraulic Engineering and Water Resources Management; Hollert, Henner; Brinkmann, Markus [RWTH Aachen Univ. (Germany). Dept. of Ecosystem Analysis; Schuettrumpf, Holger [RWTH Aachen Univ. (Germany). Inst. of Hydraulic Engineering and Water Resources Management; Manz, Werner [Koblenz-Landau Univ., Koblenz (Germany). Inst. for Integrated Natural Sciences

    2011-09-15

    Purpose: Freshwater sediments and their attached microbial communities (biofilms) are essential features of rivers and lakes, providing valuable ecosystem services such as nutrient recycling or self-purification which extend beyond the aquatic environment. Anthropogenic pollutants, whether from the industrial era or as a result of our contemporary lifestyles, can negatively affect these functions with hitherto unknown consequences on ecology, the economy and human health. Thus far, the singular view of the involved disciplines such as ecotoxicology, environmental microbiology, hydrology and geomorphology has prevented a deeper understanding of this emerging issue. Main features: This paper discusses briefly the progressions and the state-of-the-art methods within the disciplines of concern related to contaminated sediments, ranging from ecotoxicological test systems, microbiological/molecular approaches to unravel changes of microbial ecosystems, up to the modelling of sediment transport and sorption/desorption of associated pollutants. The first bilateral research efforts on contaminated sediments include efforts to assess ecotoxicological sediment risk including sediment mobility (i.e. ecotoxicology and engineering), enhance bioremediation potential (i.e. microbiology and ecotoxicology) or to understand biostabilisation processes of sediments by microbial assemblages (i.e. microbiology and engineering). Conclusions and perspectives: In freshwater habitats, acute, chronic and mechanism-specific toxic effects on organisms, shifts in composition, structure and functionality of benthic microbial communities, as well as the obstruction of important ecosystem services by continuously discharged and long-deposited pollutants, should be related to the in situ sediment dynamics. To achieve an improved understanding of the ecology of freshwater sediments and the impairment of their important ecosystem functions by human-derived pollutants, we suggest a 'triad plus x

  1. Luminescence monitoring of oil or tar contamination for industrial hygiene

    International Nuclear Information System (INIS)

    Gammage, R.B.; Vo-Dinh, T.

    1980-01-01

    Synfuel plants produce potentially carcinogenic oils and tars. Exposure of workers to these tars and oils is difficult to avoid completely and occurs via direct contact with dirty surfaces or condensation of escaped fumes onto or within the body. Surface skin, measurements are made directly with a near-ultraviolet luminoscope employing a fiber optics lightguide and a stethoscopic cap pressed against the skin. This instrument is especially suitable for measuring ng to μg/cm 2 amounts of residual contamination remaining on the surface of the skin after washing. To minimize the potential for carcinogenicity, the excitating ultraviolet light intensity is only 1/100th that of sunlight. (orig.)

  2. Forensic assessment of polycyclic aromatic hydrocarbons at the former Sydney Tar Ponds and surrounding environment using fingerprint techniques

    International Nuclear Information System (INIS)

    MacAskill, N. Devin; Walker, Tony R.; Oakes, Ken; Walsh, Margaret

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) were assessed spatially and temporally within and adjacent to a former coking and steel manufacturing facility in Sydney, Nova Scotia, Canada. Concentrations of PAHs were measured in surface soils, marine and estuary sediments prior to and during remediation of the Sydney Tar Ponds (STPs) site which was contaminated by nearly a century of coking and steel production. Previous studies identified PAHs in surficial marine sediments within Sydney Harbour, which were considered to be derived from STP discharges. Numerous PAH fingerprint techniques (diagnostic ratios, principal component analysis, quantitative and qualitative analysis) were applied to soil and sediment samples from the STPs and surrounding area to identify common source apportionment of PAHs. Results indicate coal combustion (from historical residential, commercial and industrial uses) and coal handling (from historic on-site stockpiling and current coal transfer and shipment facilities) are likely the principal source of PAHs found in urban soils and marine sediments, consistent with current and historical activities near these sites. However, PAH fingerprints associated with STP sediments correlated poorly with those of urban soils and marine sediments, but were similar to coal tar, historically consistent with by-products produced by the former coking operations. This study suggests PAH contamination of Sydney Harbour sediments and urban soils is largely unrelated to historic coking operations or recent remediation of the STPs site, but rather a legacy of extensive use of coal for a variety of activities. - Highlights: • PAHs were measured in soils and sediments near a former coking and steel facility. • Previous studies identified tar residues as main source of PAHs in marine sediments. • PAH fingerprint techniques were used to identify common source apportionment. • Fingerprint techniques indicated common sources derived from coal, not tar residues

  3. Predicting the 137Cs Contamination of Freshwater Fish in Hong Kong

    International Nuclear Information System (INIS)

    Poon, C.B.; Au, S.M.

    1999-01-01

    A predictive method for estimating the 137 Cs contamination of freshwater fish in Hong Kong after an acute deposition is presented. This method applies a published aquatic model to the freshwater fish culture ponds in Hong Kong. The predicted transfer coefficient, in terms of peak concentration in fish (wet weight) per unit deposition, is found to be generally lower than those observed in some European and UK lakes after the Chernobyl accident. While the water-fish concentration factor is undoubtedly an important factor, some unique features of the local freshwater fish culture systems, such as the absence of further radioactivity input from catchment to the fish ponds after deposition, and high removal of radioactivity by sedimentation, also play significant roles. Sensitivity of model parameters and uncertainties of prediction are also studied. This predictive model can serve as a useful tool in emergency planning and in countermeasure implementation during a nuclear emergency in Hong Kong. (author)

  4. Characterization of heavy metal concentrations in the sediments of three freshwater rivers in Huludao City, Northeast China

    International Nuclear Information System (INIS)

    Zheng Na; Wang Qichao; Liang Zhongzhu; Zheng Dongmei

    2008-01-01

    Wuli River, Cishan River, and Lianshan River are three freshwater rivers flowing through Huludao City, in a region of northeast China strongly affected by industrialization. Contamination assessment has never been conducted in a comprehensive way. For the first time, the contamination of three rivers impacted by different sources in the same city was compared. This work investigated the distribution and sources of Hg, Pb, Cd, Zn and Cu in the surface sediments of Wuli River, Cishan River, and Lianshan River, and assessed heavy metal toxicity risk with the application of two different sets of Sediment Quality Guideline (SQG) indices (effect range low/effect range median values, ERL/ERM; and threshold effect level/probable effect level, TEL/PEL). Furthermore, this study used a toxic unit approach to compare and gauge the individual and combined metal contamination for Hg, Pb, Cd, Zn and Cu. Results showed that Hg contamination in the sediments of Wuli River originated from previous sediment contamination of the chlor-alkali producing industry, and Pb, Cd, Zn and Cu contamination was mainly derived from atmospheric deposition and unknown small pollution sources. Heavy metal contamination to Cishan River sediments was mainly derived from Huludao Zinc Plant, while atmospheric deposition, sewage wastewater and unknown small pollution were the primary sources for Lianshan River. The potential acute toxicity in sediment of Wuli River may be primarily due to Hg contamination. Hg is the major toxicity contributor, accounting for 53.3-93.2%, 7.9-54.9% to total toxicity in Wuli River and Lianshan River, respectively, followed by Cd. In Cishan River, Cd is the major sediment toxicity contributor, however, accounting for 63.2-66.9% of total toxicity. - Sediment in Wuli River, Cishan River, and Lianshan River has been contaminated by heavy metals and adverse effects would be expected frequently in Wuli River and Cishan River

  5. A source mixing model to apportion PAHs from coal tar and asphalt binders in street pavements and urban aquatic sediments

    Energy Technology Data Exchange (ETDEWEB)

    Ahrens, M.J.; Depree, C.V. [National Institute of Water & Atmospheric Research, Hamilton (New Zealand)

    2010-12-15

    Present-day and more than 30 years old road and footpath pavements from Auckland, New Zealand were analysed for PAHs to test the hypothesis that coal tar based pavement binders contribute to unusually high PAH concentrations in adjacent stream and estuarine sediments Total PAH ({Sigma}{sub 28}PAH) concentrations in the dichloromethane-soluble fraction ('binder'), comprising 5-10% of pavement mass, were as high as 200 000 mg kg{sup -1}(10 000 mg kg{sup -1} in binder + aggregate) Older and deeper pavement layers were strongly pyrogenic, whereas pavement layers from recently sealed roads had a more petrogenic composition and more than 1000 times lower Sigma(28)PAH concentrations. Source identification analysis using three PAH isomer ratio pairs (benz(a)anthracene/(benz(a)anthracene + chrysene), benzo(a)pyrene/(benzo(a)pyrene + benzo(e)pyrene)), and indeno(1,2,3-cd)pyrene/(indeno(1,2,3-cd)pyrene + benzo(g,h,i)perylene) revealed low PAH (bitumen) pavements to have consistently lower isomer ratios than high PAH (coal tar) samples. A concentration-weighted mixing model, with coal tar and bitumen as source materials, explained more than 80% of the variance in isomer ratios and enveloped the entire PAH compositional and concentration range encountered PAH composition and concentrations in adjacent stream sediments ({gt} 15 mg kg{sup -1} dry weight) were consistent with diluted coal tar material as a principal PAH source. Due to the very high PAH concentrations of coal tar, a coal tar content of as little as 0.01% of total sediment mass can account for more than 90% of PAH concentrations in adjacent stream sediments.

  6. Microbiological reduction of Sb(V) in anoxic freshwater sediments

    Science.gov (United States)

    Oremland, Ronald S.; Kulp, Thomas R.; Miller, Laurence G.; Braiotta, Franco; Webb, Samuel M.; Kocar, Benjamin D; Blum, Jodi S.

    2014-01-01

    Microbiological reduction of millimolar concentrations of Sb(V) to Sb(III) was observed in anoxic sediments from two freshwater settings: (1) a Sb- and As-contaminated mine site (Stibnite Mine) in central Idaho and 2) an uncontaminated suburban lake (Searsville Lake) in the San Francisco Bay Area. Rates of Sb(V) reduction in anoxic sediment microcosms and enrichment cultures were enhanced by amendment with lactate or acetate as electron donors but not by H2, and no reduction occurred in sterilized controls. Addition of 2-14C-acetate to Stibnite Mine microcosms resulted in the production of 14CO2 coupled to Sb(V) reduction, suggesting that this process proceeds by a dissimilatory respiratory pathway in those sediments. Antimony(V) reduction in Searsville Lake sediments was not coupled to acetate mineralization and may be associated with Sb-resistance. The microcosms and enrichment cultures also reduced sulfate, and the precipitation of insoluble Sb(III)-sulfide complexes was a major sink for reduced Sb. The reduction of Sb(V) by Stibnite Mine sediments was inhibited by As(V), suggesting that As(V) is a preferred electron acceptor for the indigenous community. These findings indicate a novel pathway for anaerobic microbiological respiration and suggest that communities capable of reducing high concentrations of Sb(V) commonly occur naturally in the environment.

  7. PAHs underfoot: Contaminated dust from coal-tar sealcoated pavement is widespread in the United States

    Science.gov (United States)

    Van Metre, P.C.; Mahler, B.J.; Wilson, J.T.

    2009-01-01

    We reported in 2005 that runoff from parking lots treated with coal-tar-based sealcoat was a major source of polycyclic aromatic hydrocarbons (PAHs) to streams in Austin, Texas. Here we present new data from nine U. S. cities that show nationwide patterns in concentrations of PAHs associated with sealcoat Dust was swept from parking lots in six cities in the central and eastern U. S., where coal-tar-based sealcoat dominates use, and three cities in the western U. S., where asphalt-based sealcoat dominates use. For six central and eastern cities, median ?? PAH concentrations in dust from sealcoated and unsealcoated pavement are 2200 and 27 mg/kg, respectively. For three western cities, median ?? PAH concentrations in dust from sealcoated and unsealcoated pavement are similar and very low (2. 1 and 0. 8 mg/kg, respectively). Lakes in the central and eastern cities where pavement was sampled have bottom sediments with higher PAH concentrations than do those in the western cities relative to degree of urbanization. Bottom-sediment PAH assemblages are similar to those of sealcoated pavement dust regionally, implicating coal-tar-based sealcoat as a PAH source to the central and eastern lakes. Concentrations of benzo[a]pyrene in dust from coal-tar sealcoated pavement and adjacent soils greatly exceed generic soil screening levels, suggesting that research on human-health risk is warranted.

  8. Effect of biostimulation on the microbial community in PCB-contaminated sediments through periodic amendment of sediment with iron.

    Science.gov (United States)

    Srinivasa Varadhan, A; Khodadoust, Amid P; Brenner, Richard C

    2011-10-01

    Reductive dehalogenation of polychlorinated biphenyls (PCBs) by indigenous dehalorespiring microorganisms in contaminated sediments may be enhanced via biostimulation by supplying hydrogen generated through the anaerobic corrosion of elemental iron added to the sediment. In this study, the effect of periodic amendment of sediment with various dosages of iron on the microbial community present in sediment was investigated using phospholipid fatty acid analysis (PLFA) over a period of 18 months. Three PCB-contaminated sediments (two freshwater lake sediments and one marine sediment) were used. Signature biomarker analysis of the microbial community present in all three sediments revealed the enrichment of Dehalococcoides species, the population of which was sustained for a longer period of time when the sediment microcosms were amended with the lower dosage of iron (0.01 g iron per g dry sediment) every 6 months as compared to the blank system (without iron). Lower microbial stress levels were reported for the system periodically amended with 0.01 g of iron per g dry sediment every 6 months, thus reducing the competition from other hydrogen-utilizing microorganisms like methanogens, iron reducers, and sulfate reducers. The concentration of hydrogen in the system was found to be an important factor influencing the shift in microbial communities in all sediments with time. Periodic amendment of sediment with larger dosages of iron every 3 months resulted in the early prevalence of Geobacteraceae and sulfate-reducing bacteria followed by methanogens. An average pH of 8.4 (range of 8.2-8.6) and an average hydrogen concentration of 0.75% (range of 0.3-1.2%) observed between 6 and 15 months of the study were found to be conducive to sustaining the population of Dehalococcoides species in the three sediments amended with 0.01 g iron per g dry sediment. Biostimulation of indigenous PCB dechlorinators by the periodic amendment of contaminated sediments with low dosages of

  9. PAHs underfoot: contaminated dust from coal-tar sealcoated pavement is widespread in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Peter C. Van Metre; Barbara J. Mahler; Jennifer T. Wilson [U.S. Geological Survey, Austin, TX (USA)

    2009-01-15

    We reported in 2005 that runoff from parking lots treated with coal-tar-based sealcoat was a major source of polycyclic aromatic hydrocarbons (PAHs) to streams in Austin, Texas. Here we present new data from nine U.S. cities that show nationwide patterns in concentrations of {Sigma}PAHs associated with sealcoat. Dust was swept from parking lots in six cities in the central and eastern U.S., where coal-tar-based sealcoat dominates use, and three cities in the western U.S., where asphalt-based sealcoat dominates use. For six central and eastern cities, median SPAH concentrations in dust from sealcoated and unsealcoated pavement are 2200 and 27 mg/kg, respectively. For three western cities, median SPAH concentrations in dust from sealcoated and unsealcoated pavement are similar and very low (2.1 and 0.8 mg/kg, respectively). Lakes in the central and eastern cities where pavement was sampled have bottom sediments with higher PAH concentrations than do those in the western cities relative to degree of urbanization. Bottom-sediment PAH assemblages are similar to those of sealcoated pavement dust regionally, implicating coal-tar-based sealcoat as a PAH source to the central and eastern lakes. Concentrations of benzo(a)pyrene in dust from coal-tar sealcoated pavement and adjacent soils greatly exceed generic soil screening levels, suggesting that research on human-health risk is warranted. 30 refs., 4 figs., 2 tabs.

  10. Center for Contaminated Sediments

    Data.gov (United States)

    Federal Laboratory Consortium — The U.S. Army Corps of Engineers Center for Contaminated Sediments serves as a clearinghouse for technology and expertise concerned with contaminated sediments. The...

  11. Shoreline erosion and decadal sediment accumulation in the Tar-Pamlico estuary, North Carolina, USA: A source-to-sink analysis

    Science.gov (United States)

    Eulie, Devon O.; Corbett, D. Reide; Walsh, J. P.

    2018-03-01

    Estuaries contain vital habitats and it is important to understand how these areas respond to human activities and natural processes such as sea-level rise and wave attack. As estuarine shorelines erode or become modified with hard structures, there is potential for significantly altering the availability of sediment and the filling of coastal systems. This study used a source-to-sink approach and quantified rates of shoreline erosion in the Tar-Pamlico sub-estuary, a tributary of the larger Albemarle-Pamlico Estuarine System (APES). The average shoreline change rate (SCR) determined using an end-point method was -0.5 ± 0.9 m yr-1 for the Tar-Pamlico. Incorporating bulk density estimates, this contributes 0.6 × 105 tons of fine sediment to the system annually, or after accounting for fluvial input, about 40% of the total sediment supply to the sub-estuary. The role of the Tar-Pamlico as a sink for these sediments was addressed using the radionuclide tracers 210Pb and 137Cs. Radionuclide activities and sediment accumulation rates identified several depositional regions, in particular in the middle of the estuary. Linear sediment accumulation rates ranged from 0.10 ± 0.02 to 0.38 ± 0.02 g cm-2 yr-1, and total storage of fine sediment in the system was 1.6 × 105 t yr-1. It was not possible to confidently discern a change in the rate of shoreline erosion or seabed accumulation. A preliminary budget for fine sediments (grain-size <63 μm) was then calculated to compare erosional sources with sedimentary sinks. Almost all (∼93.0%) of the fine sediment entering the system was accumulated and stored, while only about 7.0% was exported to Pamlico Sound.

  12. Occurrence, distribution, and volume of metals-contaminated sediment of selected streams draining the Tri-State Mining District, Missouri, Oklahoma, and Kansas, 2011–12

    Science.gov (United States)

    Smith, D. Charlie

    2016-12-14

    , Tar Creek, and Spring River in order to characterize the vertical extent of mine waste in select streams in the TSMD. The largest concentrations of lead, zinc, and cadmium in gravel bar-sediment samples generally were detected in Turkey Creek and Tar Creek and the smallest concentrations were detected in Shoal Creek followed by the Spring River. Gravel bar-sediment samples from Turkey Creek exceeded the CPEC for cadmium (minimum of 70 percent of samples), lead (94 percent), and zinc (99 percent) at a slightly higher frequency than similar samples from Tar Creek (69 percent, 88 percent, and 96 percent, respectively). Gravel bar-sediment samples from Turkey Creek also contained the largest concentrations of cadmium (174 milligrams per kilogram [mg/kg]) and lead (7,520 mg/kg) detected; however, the largest zinc concentration (46,600 mg/kg) was detected in a gravel bar-sediment sample from Tar Creek. In contrast, none of the 65 gravel bar-sediment samples from Shoal Creek contained cadmium above the x-ray fluorescence reporting level of 12 mg/kg, and lead and zinc exceeded the CPEC in only 12 percent and 74 percent of samples, respectively. In most cases, concentrations of lead and zinc above the CPEC or TPEC were present at the maximum depth of boring, which indicated that nearly the entire thickness of sediment in the stream has been contaminated by mine wastes. Approximately 284,000 cubic yards of channel sediment from land surface to the maximum depth that exceeded the CPEC and approximately 236,000 cubic yards of channel sediment from land surface to the maximum depth that exceeded the TPEC were estimated along 37.6 of the 55.1 miles of Center Creek, Turkey Creek, Shoal Creek, and Tar Creek examined in this study. Mine-waste contamination reported along additional reaches of these streams is beyond the scope of this study. Flood-plain cores collected in the TSMD generally only had exceedances of the CPEC and TPEC for lead and zinc in the top 1 or 2 feet of soil with

  13. Ecological risk assessment of elemental pollution in sediment from Tunku Abdul Rahman National Park, Sabah

    Science.gov (United States)

    Elias, Md Suhaimi; Hamzah, Mohd Suhaimi; Rahman, Shamsiah Ab; Salim, Nazaratul Ashifa Abdullah; Siong, Wee Boon; Sanuri, Ezwiza

    2014-02-01

    Eleven (11) surface sediment samples were collected from Tunku Abdul Rahman National Park, Sabah. The neutron activation analysis (NAA) and inductively coupled plasma-mass spectrometry (ICP-MS) techniques were applied for the determinations metal contents and their distributions in sediment samples. The results shown that Arsenic (As) concentrations are enriched at all sampling stations except for station TAR 09, with enrichment factor (EF) values ranged from 1.1 to 7.2. The elements such as Cd, Cr, Sb and U showed enrichment at a few stations and other elements (Cr, Cu, Pb, Th, Zn) shown as background levels in all stations. Degrees of contamination in this study were calculated base on concentrations of six elements (As, Cd, Cr, Cu, Pb, and Zn). TAR 11 station can be categorized as very high degree of contamination with degree of contamination value of 43.2. TAR 07 station can be categorized as a considerable degree of contamination (contamination value of 16.9). Six stations (TAR 01, 03, 04, 05, 06, 08, 10) showed moderate degree of contamination, with contamination values ranging from 8.0 to 16.0. TAR 02 and TAR 09 stations showed low degree of contaminations (< 8.0). TAR 11 showed very high ecological risk index (RI) with RI value is 916. TAR 07 and TAR 10 showed moderate ecological risk index with RI value 263 and 213, respectively. Other stations showed low ecological risk with RI values ranging from 42.3 to 117 (< 150). Very high ecological risk index could give an adverse effect to the benthic organism. The data obtained from the enrichment factor, degree of contamination and ecological risk index provided vital information, which can be used for future comparison. Information from the present study will be useful to the relevant government agencies and authorities in preparing preventive action to control direct discharge of heavy metals from industries, agro-base activities and domestic waste to the rivers and the sea.

  14. Ecological risk assessment of elemental pollution in sediment from Tunku Abdul Rahman National Park, Sabah

    Energy Technology Data Exchange (ETDEWEB)

    Elias, Md Suhaimi; Hamzah, Mohd Suhaimi; Rahman, Shamsiah Ab; Salim, Nazaratul Ashifa Abdullah; Siong, Wee Boon; Sanuri, Ezwiza [Analytical Chemistry Application Group, Waste and Environmental Technology Division, Malaysian Nuclear Agency, Bangi 43000, Kajang, Selangor (Malaysia)

    2014-02-12

    Eleven (11) surface sediment samples were collected from Tunku Abdul Rahman National Park, Sabah. The neutron activation analysis (NAA) and inductively coupled plasma-mass spectrometry (ICP-MS) techniques were applied for the determinations metal contents and their distributions in sediment samples. The results shown that Arsenic (As) concentrations are enriched at all sampling stations except for station TAR 09, with enrichment factor (EF) values ranged from 1.1 to 7.2. The elements such as Cd, Cr, Sb and U showed enrichment at a few stations and other elements (Cr, Cu, Pb, Th, Zn) shown as background levels in all stations. Degrees of contamination in this study were calculated base on concentrations of six elements (As, Cd, Cr, Cu, Pb, and Zn). TAR 11 station can be categorized as very high degree of contamination with degree of contamination value of 43.2. TAR 07 station can be categorized as a considerable degree of contamination (contamination value of 16.9). Six stations (TAR 01, 03, 04, 05, 06, 08, 10) showed moderate degree of contamination, with contamination values ranging from 8.0 to 16.0. TAR 02 and TAR 09 stations showed low degree of contaminations (< 8.0). TAR 11 showed very high ecological risk index (R{sub I}) with RI value is 916. TAR 07 and TAR 10 showed moderate ecological risk index with R{sub I} value 263 and 213, respectively. Other stations showed low ecological risk with RI values ranging from 42.3 to 117 (< 150). Very high ecological risk index could give an adverse effect to the benthic organism. The data obtained from the enrichment factor, degree of contamination and ecological risk index provided vital information, which can be used for future comparison. Information from the present study will be useful to the relevant government agencies and authorities in preparing preventive action to control direct discharge of heavy metals from industries, agro-base activities and domestic waste to the rivers and the sea.

  15. Source Evaluation and Trace Metal Contamination in Benthic Sediments from Equatorial Ecosystems Using Multivariate Statistical Techniques.

    Directory of Open Access Journals (Sweden)

    Nsikak U Benson

    Full Text Available Trace metals (Cd, Cr, Cu, Ni and Pb concentrations in benthic sediments were analyzed through multi-step fractionation scheme to assess the levels and sources of contamination in estuarine, riverine and freshwater ecosystems in Niger Delta (Nigeria. The degree of contamination was assessed using the individual contamination factors (ICF and global contamination factor (GCF. Multivariate statistical approaches including principal component analysis (PCA, cluster analysis and correlation test were employed to evaluate the interrelationships and associated sources of contamination. The spatial distribution of metal concentrations followed the pattern Pb>Cu>Cr>Cd>Ni. Ecological risk index by ICF showed significant potential mobility and bioavailability for Cu, Cu and Ni. The ICF contamination trend in the benthic sediments at all studied sites was Cu>Cr>Ni>Cd>Pb. The principal component and agglomerative clustering analyses indicate that trace metals contamination in the ecosystems was influenced by multiple pollution sources.

  16. Influence of benthic macro-invertebrate bioturbation on the biogeochemical behaviour of uranium within freshwater sediments

    International Nuclear Information System (INIS)

    Lagauzere, S.

    2008-06-01

    In freshwater ecosystems, sediments act as an accumulation compartment for metallic pollutants as uranium. Secondary, there can also represent endogenous sources of contamination by resuspension (e.g. flood, bioturbation) or changes of metal speciation that acts upon their bioavailability. Indeed, metallic compounds can be transformed in more or less toxic or inert compounds through physico-chemical (e.g. pH, redox conditions, ionic force) and microbiological variations. These conditions are themselves under the effects of benthic macro-invertebrate activities via bioturbation processes. The main objective of this PhD was to determinate the influence of two benthic macro-invertebrate species (Chironomus riparius and Tubifex tubifex) on the distribution and the transfers of uranium within freshwater sediments. To reach this goal, laboratory experiments were performed in order to (i) assess the effects of uranium on benthic macro-invertebrates, more particularly on their bioturbation activity, (ii) determine the influence of these organisms on uranium behaviour through high resolution physico-chemical measurements (e.g. oxygen optodes, DET gel probes), and (iii) estimate the consequences of these interactions on pelagic organisms via genotoxicity measurements (micronuclei assay and molecular bio-markers analysis on Xenopus laevis). The results demonstrate that bioturbation intensity of macro-invertebrates can be affected in uranium-contaminated sediments, but the two species studied in this work show a relative tolerance. For high uranium concentrations (>100 times the geochemical background level), corresponding however to realistic concentrations in highly contaminated sites, T. tubifex worms are able to maintain a sufficient bioturbation activity that induces a high remobilization of uranium initially associated with sediments to the overlying water (factor 2 to 10). That represents therefore a potential risk for the remaining aquatic biocenose. However, by

  17. PAH concentrations in lake sediment decline following ban on coal-tar-based pavement sealants in Austin, Texas

    Science.gov (United States)

    Van Metre, Peter C.; Mahler, Barbara J.

    2013-01-01

    Recent studies have concluded that coal-tar-based pavement sealants are a major source of polycyclic aromatic hydrocarbons (PAHs) in urban settings in large parts of the United States. In 2006, Austin, TX, became the first jurisdiction in the U.S. to ban the use of coal-tar sealants. We evaluated the effect of Austin’s ban by analyzing PAHs in sediment cores and bottom-sediment samples collected in 1998, 2000, 2001, 2012, and 2014 from Lady Bird Lake, the principal receiving water body for Austin urban runoff. The sum concentration of the 16 EPA Priority Pollutant PAHs (∑PAH16) in dated core intervals and surficial bottom-sediment samples collected from sites in the lower lake declined about 44% from 1998–2005 to 2006–2014 (means of 7980 and 4500 μg kg–1, respectively), and by 2012–2014, the decline was about 58% (mean of 3320 μg kg–1). Concentrations of ∑PAH16 in bottom sediment from two of three mid-lake sites decreased by about 71 and 35% from 2001 to 2014. Concentrations at a third site increased by about 14% from 2001 to 2014. The decreases since 2006 reverse a 40-year (1959–1998) upward trend. Despite declines in PAH concentrations, PAH profiles and source-receptor modeling results indicate that coal-tar sealants remain the largest PAH source to the lake, implying that PAH concentrations likely will continue to decline as stocks of previously applied sealant gradually become depleted.

  18. Freshwater sediments and sludges: two important terrestrial sinks for emissions from damaged NPPs

    Science.gov (United States)

    Fischer, Helmut W.; Evangelia Souti, Maria; Ulbrich, Susanne; Hormann, Volker

    2013-04-01

    Surface deposition of radionuclides released from the damaged Fukushima NPPs is well documented and emissions to the Pacific Ocean and their distribution with time and space are also subject to monitoring and research. In both cases, solid matter (soil and sea sediment, respectively) acts as a sink for radioisotopes after their transport through air and water. The possible hazards from direct irradiation of workers and public and from entry of radionuclides into food chains are well recognized. Apart from direct deposition onto soil, plants, building roofs etc., aerosols and contaminated rainwater will reach surface waters, leading to long-term deposition in freshwater sediments (and possibly to interim contamination of drinking water). In populated and industrial areas, drained rainwater will enter the wastewater collection and treatment chain if a combined rain and wastewater sewer is used. Depending on the processes in the wastewater treatment plant and chemical element and speciation, the isotopes will either concentrate in treatment sludge or be released with the effluent to rivers and lakes and their sediments. The mentioned media may act as long-term storage for radioisotopes when disposed of properly, but can also contribute to direct irradiation of workers or public, lead to continuous releases to the environment and possibly enter the food chain in the same way as soil and sea sediments. It appears therefore essential to monitor these environmental compartments as well. However, very few data on Fukushima-related radioisotope concentration in sludges and freshwater sediments have been published to date. We will therefore compare data for regional surface deposition and related concentrations in surface water, river sediments and sewage sludge obtained in Europe during 1986 to published data from Japan in 2011 for the most important common short-lived (I-131, half-life = 8.02 d) and long-lived (Cs-137, half-life = 30.17 yr) isotopes. As in central Europe

  19. Physicochemical characteristics of radionuclides associated with sediment from a contaminated fresh water stream

    International Nuclear Information System (INIS)

    Murdock, R.N.; Hemingway, J.D.; Jones, S.R.

    1993-01-01

    The relationships between concentrations of 241 Am, 137 Cs and 239,240 Pu and sediment particle size and geochemical species were examined for sediments taken from a freshwater stream contaminated by radioactive effluent from a low-level waste disposal site. Both 137 Cs and gross alpha concentrations were strongly correlated with the silt and clay content of the sediment, radionuclide concentrations following the order: clay>silt>sand. Positive correlations with organic content were also observed for both 137 Cs and gross alpha activity. These relationships, together with erosional and depositional characteristics obtained from streamflow data, largely explained the spatial variation in radionuclide concentrations in streambed sediments. Sequential extraction experiments showed that 137 Cs was mostly ''irreversibly'' bound to sediment particle, principally illitic clays, whereas 241 Am and 239,240 Pu were associated primarily with organic and oxy-hydroxy species within the sediments. (Author)

  20. Suspended sediment and sediment-associated contaminants in San Francisco Bay

    Science.gov (United States)

    Schoellhamer, D.H.; Mumley, T.E.; Leatherbarrow, J.E.

    2007-01-01

    Water-quality managers desire information on the temporal and spatial variability of contaminant concentrations and the magnitudes of watershed and bed-sediment loads in San Francisco Bay. To help provide this information, the Regional Monitoring Program for Trace Substances in the San Francisco Estuary (RMP) takes advantage of the association of many contaminants with sediment particles by continuously measuring suspended-sediment concentration (SSC), which is an accurate, less costly, and more easily measured surrogate for several trace metals and organic contaminants. Continuous time series of SSC are collected at several sites in the Bay. Although semidiurnal and diurnal tidal fluctuations are present, most of the variability of SSC occurs at fortnightly, monthly, and semiannual tidal time scales. A seasonal cycle of sediment inflow, wind-wave resuspension, and winnowing of fine sediment also is observed. SSC and, thus, sediment-associated contaminants tend to be greater in shallower water, at the landward ends of the Bay, and in several localized estuarine turbidity maxima. Although understanding of sediment transport has improved in the first 10 years of the RMP, determining a simple mass budget of sediment or associated contaminants is confounded by uncertainties regarding sediment flux at boundaries, change in bed-sediment storage, and appropriate modeling techniques. Nevertheless, management of sediment-associated contaminants has improved greatly. Better understanding of sediment and sediment-associated contaminants in the Bay is of great interest to evaluate the value of control actions taken and the need for additional controls. ?? 2007 Elsevier Inc. All rights reserved.

  1. Ecological risk assessment of elemental pollution in sediment from Tunku Abdul Rahman National Park, Sabah

    International Nuclear Information System (INIS)

    Elias, Md Suhaimi; Hamzah, Mohd Suhaimi; Rahman, Shamsiah Ab; Salim, Nazaratul Ashifa Abdullah; Siong, Wee Boon; Sanuri, Ezwiza

    2014-01-01

    Eleven (11) surface sediment samples were collected from Tunku Abdul Rahman National Park, Sabah. The neutron activation analysis (NAA) and inductively coupled plasma-mass spectrometry (ICP-MS) techniques were applied for the determinations metal contents and their distributions in sediment samples. The results shown that Arsenic (As) concentrations are enriched at all sampling stations except for station TAR 09, with enrichment factor (EF) values ranged from 1.1 to 7.2. The elements such as Cd, Cr, Sb and U showed enrichment at a few stations and other elements (Cr, Cu, Pb, Th, Zn) shown as background levels in all stations. Degrees of contamination in this study were calculated base on concentrations of six elements (As, Cd, Cr, Cu, Pb, and Zn). TAR 11 station can be categorized as very high degree of contamination with degree of contamination value of 43.2. TAR 07 station can be categorized as a considerable degree of contamination (contamination value of 16.9). Six stations (TAR 01, 03, 04, 05, 06, 08, 10) showed moderate degree of contamination, with contamination values ranging from 8.0 to 16.0. TAR 02 and TAR 09 stations showed low degree of contaminations ( I ) with RI value is 916. TAR 07 and TAR 10 showed moderate ecological risk index with R I value 263 and 213, respectively. Other stations showed low ecological risk with RI values ranging from 42.3 to 117 (< 150). Very high ecological risk index could give an adverse effect to the benthic organism. The data obtained from the enrichment factor, degree of contamination and ecological risk index provided vital information, which can be used for future comparison. Information from the present study will be useful to the relevant government agencies and authorities in preparing preventive action to control direct discharge of heavy metals from industries, agro-base activities and domestic waste to the rivers and the sea

  2. Ecological risk assessment of elemental pollution in sediment from Tunku Abdul Rahman National Park, Sabah

    International Nuclear Information System (INIS)

    Mohd Suhaimi Elias; Mohd Suhaimi Hamzah; Shamsiah Abdul Rahman; Nazaratul Ashifa Abdullah Salim; Wee, B.S.; Ezwiza Sanuri

    2013-01-01

    Full-text: Eleven (11) surface sediment samples were collected from Tunku Abdul Rahman National Park, Sabah. The neutron activation analysis (NAA) and inductively coupled plasma-mass spectrometry (ICP-MS) techniques were applied for the determinations metal contents and their distributions in sediment samples. The results shown that Arsenic (As) concentrations are enriched at all sampling stations except for station TAR 09, with enrichment factor (EF) values ranged from 1.1 to 7.2. The elements such as Cd, Cr, Sb and U showed enrichment at a few stations and other elements (Cr, Cu, Pb, Th, Zn) shown as background levels in all stations. Degrees of contamination in this study were calculated base on concentrations of six elements (As, Cd, Cr, Cu, Pb, and Zn). TAR 11 station can be categorized as very high degree of contamination with degree of contamination value of 43.2. TAR 07 station can be categorized as a considerable degree of contamination (contamination value of 16.9). Six stations (TAR 01, 03, 04, 05, 06, 08, 10) showed moderate degree of contamination, with contamination values ranging from 8.0 to 16.0. TAR 02 and TAR 09 stations showed low degree of contaminations ( I ) with R I value is 916. TAR 07 and TAR 10 showed moderate ecological risk index with R I value 263 and 213, respectively. Other stations showed low ecological risk with R I values ranging from 42.3 to 117 (< 150). Very high ecological risk index could give an adverse effect to the benthic organism. The data obtained from the enrichment factor, degree of contamination and ecological risk index provided vital information, which can be used for future comparison. Information from the present study will be useful to the relevant government agencies and authorities in preparing preventive action to control direct discharge of heavy metals from industries, agro-base activities and domestic waste to the rivers and the sea. (author)

  3. Toxicity of lead-contaminated sediment to mallards

    Science.gov (United States)

    Heinz, G.H.; Hoffman, D.J.; Sileo, L.; Audet, D.J.; LeCaptain, L.J.

    1999-01-01

    Because consumption of lead-contaminated sediment has been suspected as the cause of waterfowl mortality in the Coeur d?Alene River basin in Idaho, we studied the bioavailability and toxicity of this sediment to mallards (Anas platyrhynchos). In experiment 1, one of 10 adult male mallards died when fed a pelleted commercial duck diet that contained 24% lead-contaminated sediment (with 3,400 μg/g lead in the sediment). Protoporphyrin levels in the blood increased as the percentage of lead-contaminated sediment in the diet increased. Birds fed 24% lead-contaminated sediment exhibited atrophy of the breast muscles, green staining of the feathers around the vent, viscous bile, green staining of the gizzard lining, and renal tubular intranuclear inclusion bodies. Mallards fed 24% lead-contaminated sediment had means of 6.1 μg/g of lead in the blood and 28 μg/g in the liver (wet-weight basis) and 1,660 μg/g in the feces (dry-weight basis). In experiment 2, we raised the dietary concentration of the lead-contaminated sediment to 48%, but only about 20% sediment was actually ingested due to food washing by the birds. Protoporphyrin levels were elevated in the lead-exposed birds, and all of the mallards fed 48% lead-contaminated sediment had renal tubular intranuclear inclusion bodies. The concentrations of lead in the liver were 9.1 μg/g for mallards fed 24% lead-contaminated sediment and 16 μg/g for mallards fed 48% lead-contaminated sediment. In experiment 3, four of five mallards died when fed a ground corn diet containing 24% lead-contaminated sediment (with 4,000 μg/g lead in this sample of sediment), but none died when the 24% lead-contaminated sediment was mixed into a nutritionally balanced commercial duck diet; estimated actual ingestion rates for sediment were 14% and 17% for the corn and commercial diets. Lead exposure caused elevations in protoporphyrin, and four of the five mallards fed 24% lead-contaminated sediment in a commercial diet and all five

  4. Bacterial reduction of selenium in coal mine tailings pond sediment

    Energy Technology Data Exchange (ETDEWEB)

    Siddique, T.; Arocena, J.M.; Thring, R.W.; Zhang, Y.Q. [University of North British Columbia, Prince George, BC (Canada)

    2007-05-15

    Sediment from a storage facility for coal tailings solids was assessed for its capacity to reduce selenium (Se) by native bacterial community. One Se{sup 6+}-reducing bacterium Enterobacter hormaechei (Tar11) and four Se{sup 4+}-reducing bacteria, Klebsiella pneumoniae (Tar1), Pseudomonasfluorescens (Tar3), Stenotrophomonas maltophilia (Tar6), and Enterobacter amnigenus (Tar8) were isolated from the sediment. Enterobacter horinaechei removed 96% of the added Se{sup 6+} (0.92 mg L{sup -1} from the effluents when Se6+ was determined after 5 d of incubation. Analysis of the red precipitates showed that Se{sup 6+} reduction resulted in the formation of spherical particles ({lt}1.0 {mu} m) of Se 0 as observed under scanning electron microscope (SEM) and confirmed by EDAX. Selenium speciation was performed to examine the fate of the added Se{sup 6+} in the sediment with or without addition of Enterobacter hormaechei cells. More than 99% of the added Se{sup 6+} (about 2.5 mg L{sup -1}) was transformed in the nonsterilized sediment (without Enterobacter hormaechei cells) as well as in the sterilized (heat-killed) sediment (with Enterobacter hormaechei cells). The results of this study suggest that the lagoon sediments at the mine site harbor Se{sup 6+}- and Se{sup 4+} -reducing bacteria and may be important sinks for soluble Se (Se{sup 6+} and Se{sup 4+}). Enterobacter hormaechei isolated from metal-contaminated sediment may have potential application in removing Se from industrial effluents.

  5. Green remediation of contaminated sediment by stabilization/solidification with industrial by-products and CO2 utilization.

    Science.gov (United States)

    Wang, Lei; Chen, Liang; Tsang, Daniel C W; Li, Jiang-Shan; Yeung, Tiffany L Y; Ding, Shiming; Poon, Chi Sun

    2018-08-01

    Navigational dredging is an excavation of marine/freshwater sediment to maintain channels of sufficient depth for shipping safety. Due to historical inputs of anthropogenic contaminants, sediments are often contaminated by metals/metalloids, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and other contaminants. Its disposal can present significant environmental and financial burdens. This study developed a novel and green remediation method for contaminated sediment using stabilization/solidification with calcium-rich/low-calcium industrial by-products and CO 2 utilization. The hydration products were evaluated by quantitative X-ray diffraction analysis and thermogravimetric analysis. The incorporation of calcium carbide residue (CCR) facilitated hydration reaction and provided relatively high 7-d strength. In contrast, the addition of Class-F pulverized fly ash (PFA) and ground granulated blast furnace slag (GGBS) was beneficial to the 28-d strength development due to supplementary pozzolanic and hydration reactions. The employment of 1-d CO 2 curing was found to promote strength development (98%) and carbon sequestration (4.3wt%), while additional 7-d air curing facilitated cement rehydration and further carbonation in the sediment blocks. The leachability tests indicated that all studied binders, especially CCR binder, effectively immobilized contaminants in the sediments. The calcium-rich CCR and GGBS were regarded as promising candidates for augmenting the efficacy of CO 2 curing, whereas GGBS samples could be applicable as eco-paving blocks in view of their superior 28-d strength. This study presents a new and sustainable way to transform contaminated sediment into value-added materials. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Potential contributions of asphalt and coal tar to black carbon quantification in urban dust, soils, and sediments

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Y.; Mahler, B.J.; Van Metre, P.C.; Ligouis, B.; Werth, C.J. [University of Illinois Urbana Champaign, Urbana, IL (USA). Dept. of Civil & Environmental Engineering

    2010-12-01

    Measurements of black carbon (BC) using either chemical or thermal oxidation methods are generally thought to indicate the amount of char and/or soot present in a sample. In urban environments, however, asphalt and coal-tar particles worn from pavement are ubiquitous and, because of their pyrogenic origin, could contribute to measurements of BC. Here we explored the effect of the presence of asphalt and coal-tar particles on the quantification of BC in a range of urban environmental sample types, and evaluated biases in the different methods used for quantifying BC. Samples evaluated were pavement dust, residential and commercial area soils, lake sediments from a small urban watershed, and reference materials of asphalt and coal tar. Total BC was quantified using chemical treatment through acid dichromate (Cr{sub 2}O{sub 7}) oxidation and chemo-thermal oxidation at 375{sup o}C (CTO-375). BC species, including soot and char/charcoal, asphalt, and coal tar, were quantified with organic petrographic analysis. Comparison of results by the two oxidation methods and organic petrography indicates that both coal tar and asphalt contribute to BC quantified by Cr{sub 2}O{sub 7} oxidation, and that coal tar contributes to BC quantified by CTO-375. These results are supported by treatment of asphalt and coal-tar reference samples with Cr2O7 oxidation and CTO-375. The reference asphalt is resistant to Cr{sub 2}O{sub 7} oxidation but not to CTO-375, and the reference coal tar is resistant to both Cr2O7 oxidation and CTO-375. These results indicate that coal tar and/or asphalt can contribute to BC measurements in samples from urban areas using Cr{sub 2}O{sub 7} oxidation or CTO-375, and caution is advised when interpreting BC measurements made with these methods.

  7. Endocrine effects of contaminated sediments on the freshwater snail Potamopyrgus antipodarum in vivo and in the cell bioassays in vitro.

    Science.gov (United States)

    Mazurová, E; Hilscherová, K; Jálová, V; Köhler, H-R; Triebskorn, R; Giesy, J P; Bláha, L

    2008-09-17

    Lake Pilnok located in the black coal-mining region Ostrava-Karvina, Czech Republic, contains sediments highly contaminated with powdered waste coal. Moreover, population of the endangered species of narrow-clawed crayfish Pontastacus leptodactylus with high proportion of intersex individuals (18%) was observed at this site. These findings motivated our work that aimed to evaluate contamination, endocrine disruptive potency using in vitro assays and in vivo effects of contaminated sediments on reproduction of sediment-dwelling invertebrates. Chemical analyses revealed low concentrations of persistent chlorinated compounds and heavy metals but concentrations of polycyclic aromatic hydrocarbons (PAH) were high (sum of 16 PAHs 10 microg/g dw). Organic extracts from sediments caused significant in vitro AhR-mediated activity in the bioassay with H4IIE-luc cells, estrogenicity in MVLN cells and anti-androgenicity in recombinant yeast assay, and these effects could be attributed to non-persistent compounds derived from the waste coal. We have also observed significant in vivo effects of the sediments in laboratory experiments with the Prosobranchian euryhaline mud snail Potamopyrgus antipodarum. Sediments from Lake Pilnok as well as organic extracts of the sediments (externally added to the control sediment) significantly affected fecundity during 8 weeks of exposure. The effects were stimulations of fecundity at lower concentrations at the beginning of the experiment followed by inhibitions of fecundity and general toxicity. Our study indicates presence of chemicals that affected endocrine balance in invertebrates, and emphasizes the need for integrated approaches combining in vitro and in vivo bioassays with identification of chemicals to elucidate ecotoxicogical impacts of contaminated sediment samples.

  8. Ecological risk assessment of heavy metal in surface sediment collected from Tuanku Abdul Rahman National Park, Sabah

    International Nuclear Information System (INIS)

    Mohd Suhaimi Elias; Mohd Suhaimi Hamzah; Shamsiah Abdul Rahman; Nazaratul Ashifa Abdullah Salim; Wee Boon Siong; Ezwiza Sanuri

    2012-01-01

    Eleven (11) surface sediment samples were collected from Tuanku Abdul Rahman National Park, Sabah. The neutron activation analysis (NAA) and inductively coupled plasma-mass spectrometry (ICP-MS) techniques were applied for the determinations of the heavy metal contents and their distributions in sediment samples of Tuanku Abdul Rahman National Park. The results shown that Arsenic (As) concentrations are enriched in all sampling stations except station TAR 09, with enrichment factor (EF) values ranged from 1.1-7.2. The elements such as Cd, Cr, Sb and U showed enrichment in a few stations and other elements (Cr, Cu, Pb, Th, Zn) shown as background levels in all stations. Degrees of contamination in this study were calculated base on concentrations of six elements (As, Cd, Cr, Cu, Pb, and Zn). TAR11 station can be categorized as very high degree of contamination with degree of contamination value of 43.2. TAR07 station can be categorized as considerable degree of contamination (contamination value of 16.9). Six stations (TAR01, 03, 04, 05, 06, 08, 10) showed moderate degree of contamination, with contamination values ranging from 8.0-16.0. TAR02 and TAR09 stations showed low degree of contaminations ( I ) with value of R I I I I ≥ 600, respectively. TAR11 showed very high ecological risk index with R I value is 916. TAR07 and TAR10 showed moderate ecological risk index with R I value 263 and 213, respectively. Other stations showed low ecological risk with R I values ranging from 42.3 - 117 (< 150). Very high ecological risk index could give an adverse effect the marine or benthic organism. The data obtained from the enrichment factor, degree of contamination and ecological risk index provided vital information, which can be used for future comparison. Information from the present study will be useful to the relevant government agencies and authorities in preparing preventive action to control of heavy metal and other pollutants from industries, agro-base activities

  9. Biogenic silica in tidal freshwater marsh sediments and vegetation (Schelde estuary, Belgium)

    NARCIS (Netherlands)

    Struyf, E.; van Damme, S.; Gribsholt, B.; Middelburg, J.J.; Meire, P.

    2005-01-01

    To date, estuarine ecosystem research has mostly neglected silica cycling in freshwater intertidal marshes. However, tidal marshes can store large amounts of biogenic silica (BSi) in vegetation and sediment. BSi content of the typical freshwater marsh plants Phragmites australis, Impatiens

  10. Contaminated sediment transport during floods

    International Nuclear Information System (INIS)

    Fontaine, T.A.

    1992-01-01

    Over the past 48 years, operations and waste disposal activities at Oak Ridge National Laboratory have resulted in the contamination of parts of the White Oak Creek catchment. The contaminants presenting the highest risk to human health and the environment are particle reactive and are associated with the soils and sediments in the White Oak Creek drainage system. The erosion of these sediments during floods can result in the transport of contaminants both within the catchment and off-site into the Clinch River. A data collection program and a modeling investigation are being used to evaluate the probability of contaminated sediment transport during floods and to develop strategies for controlling off-site transport under present and future conditions

  11. Toxicity of nickel-spiked freshwater sediments to benthic invertebrates-Spiking methodology, species sensitivity, and nickel bioavailability

    Science.gov (United States)

    Besser, John M.; Brumbaugh, William G.; Kemble, Nile E.; Ivey, Chris D.; Kunz, James L.; Ingersoll, Christopher G.; Rudel, David

    2011-01-01

    This report summarizes data from studies of the toxicity and bioavailability of nickel in nickel-spiked freshwater sediments. The goal of these studies was to generate toxicity and chemistry data to support development of broadly applicable sediment quality guidelines for nickel. The studies were conducted as three tasks, which are presented here as three chapters: Task 1, Development of methods for preparation and toxicity testing of nickel-spiked freshwater sediments; Task 2, Sensitivity of benthic invertebrates to toxicity of nickel-spiked freshwater sediments; and Task 3, Effect of sediment characteristics on nickel bioavailability. Appendices with additional methodological details and raw chemistry and toxicity data for the three tasks are available online at http://pubs.usgs.gov/sir/2011/5225/downloads/.

  12. Characterization of freshwater mosses as indicators of radioactive contamination

    International Nuclear Information System (INIS)

    Beaugelin-Seiller, K.

    1994-01-01

    The necessity of indicators of freshwater contamination has developed the interest for aquatic mosses. From a fundamental point of view, studying the influence of some biotic and abiotic factors has permitted to better know the mechanisms of radionuclides accumulation by these bryophytes. From a radioecological point of view, simulating real cases of water contamination has allowed to give results a very interesting representativeness. The use of mosses as bio-indicators was applied for two in situ experiments, the results of which have been interpreted from those obtained in laboratory. Finally, an approach by a mathematical model has showed that it is possible to have, in a middle term, an evaluation tool of freshwater contamination, based on the radionuclides concentrations measured in aquatic mosses. (author). refs., 57 figs., 24 tabs

  13. Acid Tar Lagoons: Management and Recovery

    Science.gov (United States)

    Bohers, Anna; Hroncová, Emília; Ladomerský, Juraj

    2017-04-01

    liquid state et sim. Because of lack of geological research caused by fragile limestone bedrock under the lagoon in combination with aggressive substance in the lagoon, waste management of this contaminated site became even more complicated. The main aim of this work is to present by analysis a new possibility of acid tarry-waste management thanks to the technique of thermal desorption as a method for acid tar processing, through which it is possible to gain only organic part; and a technology of Blowing Decomposition as a method for its consequent recovery. Thermal desorption process is an effective separation process through which is possible to split acid tarry material into matrix (soil, sediments) and organic contaminants (PCB and POPs compounds). The process is carried out through a mobile unit which is relocatable. The work also presents a relation between volume of de-contaminated matrix and organic compounds. In order to boost the efficiency in processing of acid tar waste through thermal desorption, the work will present possibility of application of innovative technology - method of Blowing Decomposition for recovering of organic matter into technological lubricating oil.

  14. Characterizing toxicity of metal-contaminated sediments from mining areas

    Science.gov (United States)

    Besser, John M.; Brumbaugh, William G.; Ingersoll, Christopher G.

    2015-01-01

    This paper reviews methods for testing the toxicity of metals associated with freshwater sediments, linking toxic effects with metal exposure and bioavailability, and developing sediment quality guidelines. The most broadly applicable approach for characterizing metal toxicity is whole-sediment toxicity testing, which attempts to simulate natural exposure conditions in the laboratory. Standard methods for whole-sediment testing can be adapted to test a wide variety of taxa. Chronic sediment tests that characterize effects on multiple endpoints (e.g., survival, growth, and reproduction) can be highly sensitive indicators of adverse effects on resident invertebrate taxa. Methods for testing of aqueous phases (pore water, overlying water, or elutriates) are used less frequently. Analysis of sediment toxicity data focuses on statistical comparisons between responses in sediments from the study area and responses in one or more uncontaminated reference sediments. For large or complex study areas, a greater number of reference sediments is recommended to reliably define the normal range of responses in uncontaminated sediments – the ‘reference envelope’. Data on metal concentrations and effects on test organisms across a gradient of contamination may allow development of concentration-response models, which estimate metal concentrations associated with specified levels of toxic effects (e.g. 20% effect concentration or EC20). Comparisons of toxic effects in laboratory tests with measures of impacts on resident benthic invertebrate communities can help document causal relationships between metal contamination and biological effects. Total or total-recoverable metal concentrations in sediments are the most common measure of metal contamination in sediments, but metal concentrations in labile sediment fractions (e.g., determined as part of selective sediment extraction protocols) may better represent metal bioavailability. Metals released by the weak-acid extraction

  15. Preliminary evaluation of ground-water contamination by coal-tar derivatives, St. Louis Park area, Minnesota

    Science.gov (United States)

    Hult, Marc F.; Schoenberg, Michael E.

    1984-01-01

    Operation of a coal-tar distillation and wood-preserving plant from 1918 to 1972 in St. Louis Park, a suburb of Minneapolis, Minn., resulted in ground-water contamination. This preliminary evaluation presents an overview of the problem based on the results of the first year (1979) of an ongoing study.

  16. Spatial distribution of ammonia-oxidizing archaea and bacteria across eight freshwater lakes in sediments from Jiangsu of China

    Directory of Open Access Journals (Sweden)

    Xu Sun

    2014-03-01

    Full Text Available Ammonia-oxidizingarchaea (AOA and ammonia-oxidizing bacteria (AOB play an important role innitrogen transformation in freshwater sediments. However, it is still unclear towhat extent the distribution patterns of these microorganisms are affected bythe freshwater sediment across a large geographical scale. This study wasdesigned to gain insight into the heterogeneity distribution of AOA and AOB in32 freshwater sediments from a wide range of ecologic types. Real-time quantitative polymerasechain reaction PCR(qPCR combined with the terminal restrictionfragment length polymorphism(T-RFLP were employed to characterize the abundance, diversity, and communitystructure of the AOA and AOB in 32 freshwater sediments. AOA and AOB wereubiquitous in all sediments, and archaeal amoA far outnumbered bacterial amoA inmost sediments with lower organic matters. The abundance of AOA and AOB did notvary with the freshwater ecological type (macrophyte dominated region and algaedominated region. Based on  the T-RFLP of an amoA gene, this research found that organicmatters in pore water rather than other factors affect the AOA communitystructure in sediments, while the AOB were not significantly different in thefreshwater sediments. Phylogenetic analysis showed that all archaeal amoAsequences fell within either the Crenarchaeotal Group (CG I.1b or the CGI.1asubgroup, and all AOB clustered with genus Nitrosomonas or Nitrosospira. The data obtained inthis study elucidates the role of ammonia-oxidizing archaea andammonia-oxidizing bacteria in the nitrogen cycle of freshwater ecosystems.

  17. Effects of turbidity, sediment, and polyacrylamide on native freshwater mussels

    Science.gov (United States)

    Buczek, Sean B.; Cope, W. Gregory; McLaughlin, Richard A.; Kwak, Thomas J.

    2018-01-01

    Turbidity is a ubiquitous pollutant adversely affecting water quality and aquatic life in waterways globally. Anionic polyacrylamide (PAM) is widely used as an effective chemical flocculent to reduce suspended sediment (SS) and turbidity. However, no information exists on the toxicity of PAM‐flocculated sediments to imperiled, but ecologically important, freshwater mussels (Unionidae). Thus, we conducted acute (96 h) and chronic (24 day) laboratory tests with juvenile fatmucket (Lampsilis siliquoidea) and three exposure conditions (nonflocculated settled sediment, SS, and PAM‐flocculated settled sediment) over a range of turbidity levels (50, 250, 1,250, and 3,500 nephelometric turbidity units). Survival and sublethal endpoints of protein oxidation, adenosine triphosphate (ATP) production, and protein concentration were used as measures of toxicity. We found no effect of turbidity levels or exposure condition on mussel survival in acute or chronic tests. However, we found significant reductions in protein concentration, ATP production, and oxidized proteins in mussels acutely exposed to the SS condition, which required water movement to maintain sediment in suspension, indicating responses that are symptoms of physiological stress. Our results suggest anionic PAM applied to reduce SS may minimize adverse effects of short‐term turbidity exposure on juvenile freshwater mussels without eliciting additional lethal or sublethal toxicity.

  18. Metal impacts on microbial biomass in the anoxic sediments of a contaminated lake

    Energy Technology Data Exchange (ETDEWEB)

    Gough, Heidi L.; Dahl, Amy L.; Nolan, Melissa A.; Gaillard, Jean-Francois; Stahl, David A.

    2008-04-26

    Little is known about the long-term impacts of metal contamination on the microbiota of anoxic lake sediments. In this study, we examined microbial biomass and metals (arsenic, cadmium, chromium, copper, iron, lead, manganese, and zinc) in the sediments of Lake DePue, a backwater lake located near a former zinc smelter. Sediment core samples were examined using two independent measures for microbial biomass (total microscopic counts and total phospholipid-phosphate concentrations), and for various fractions of each metal (pore water extracts, sequential extractions, and total extracts of all studied metals and zinc speciation by X-ray absorption fine structure (XAFS). Zinc concentrations were up to 1000 times higher than reported for sediments in the adjacent Illinois River, and ranged from 21,400 mg/kg near the source to 1,680 mg/kg near the river. However, solid metal fractions were not well correlated with pore water concentrations, and were not good predictors of biomass concentrations. Instead, biomass, which varied among sites by as much as two-times, was inversely correlated with concentrations of pore water zinc and arsenic as established by multiple linear regression. Monitoring of other parameters known to naturally influence biomass in sediments (e.g., organic carbon concentrations, nitrogen concentrations, pH, sediment texture, and macrophytes) revealed no differences that could explain observed biomass trends. This study provides strong support for control of microbial abundance by pore water metal concentrations in contaminated freshwater sediments.

  19. Contamination of Omnivorous Freshwater Fish Species and Sediments by Chlorinated Hydrocarbons in Poland

    Directory of Open Access Journals (Sweden)

    Niewiadowska Alicja

    2014-10-01

    Full Text Available The occurrence and concentrations of organochlorine pesticides and polychlorinated biphenyls (PCBs were determined in 158 muscle samples of bream (Abramis brama and roach (Rutilus rutilus, and 84 samples of sediments collected from 10 river and lake sampling sites in 2011 and 2012. The concentrations of DDTs (p,p’-DDT, o,p’-DDT, p,p’-DDE, and p,p’-DDD, HCH isomers (a-, ß-, and y-HCH, HCB, and PCBs (six indicator PCB congeners 28, 52, 101, 138, 153 and 180 were determined using the capillary gas chromatography. The mean concentrations of DDTs in bream and roach were in the range of 11.2-654 and 4.5-121 ug/kg wet weight respectively, and PCBs were in the range of 1.3-75.9 and 1.1-112 ug/kg wet weight, respectively. Mean concentrations of DDTs and PCBs in sediments were 0.5-270 ug/kg dry weight and ⋋0.1-2.2 ug/kg dry weight respectively. The study showed clear spatial differences in the levels of organochlorine pesticides and PCBs in fish and sediments from different aquatic ecosystems. The highest levels of contaminants were detected in fish and sediments from the Vistula River in vicinity of Cracow. The possible risk to the fish meat consumers and ecological risk were evaluated.

  20. Assessment of sources of human pathogens and fecal contamination in a Florida freshwater lake.

    Science.gov (United States)

    Staley, Christopher; Reckhow, Kenneth H; Lukasik, Jerzy; Harwood, Valerie J

    2012-11-01

    We investigated the potential for a variety of environmental reservoirs to harbor or contribute fecal indicator bacteria (FIB), DNA markers of human fecal contamination, and human pathogens to a freshwater lake. We hypothesized that submerged aquatic vegetation (SAV), sediments, and stormwater act as reservoirs and/or provide inputs of FIB and human pathogens to this inland water. Analysis included microbial source tracking (MST) markers of sewage contamination (Enterococcus faecium esp gene, human-associated Bacteroides HF183, and human polyomaviruses), pathogens (Salmonella, Cryptosporidium, Giardia, and enteric viruses), and FIB (fecal coliforms, Escherichia coli, and enterococci). Bayesian analysis was used to assess relationships among microbial and physicochemical variables. FIB in the water were correlated with concentrations in SAV and sediment. Furthermore, the correlation of antecedent rainfall and major rain events with FIB concentrations and detection of human markers and pathogens points toward multiple reservoirs for microbial contaminants in this system. Although pathogens and human-source markers were detected in 55% and 21% of samples, respectively, markers rarely coincided with pathogen detection. Bayesian analysis revealed that low concentrations (<45 CFU × 100 ml(-1)) of fecal coliforms were associated with 93% probability that pathogens would not be detected; furthermore the Bayes net model showed associations between elevated temperature and rainfall with fecal coliform and enterococci concentrations, but not E. coli. These data indicate that many under-studied matrices (e.g. SAV, sediment, stormwater) are important reservoirs for FIB and potentially human pathogens and demonstrate the usefulness of Bayes net analysis for water quality assessment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Perfluoroalkyl acid contamination and polyunsaturated fatty acid composition of French freshwater and marine fishes.

    Science.gov (United States)

    Yamada, Ami; Bemrah, Nawel; Veyrand, Bruno; Pollono, Charles; Merlo, Mathilde; Desvignes, Virginie; Sirot, Véronique; Oseredczuk, Marine; Marchand, Philippe; Cariou, Ronan; Antignac, Jean-Phillippe; Le Bizec, Bruno; Leblanc, Jean-Charles

    2014-07-30

    In this study, French marine and freshwater fish perfluoroalkyl acid (PFAA) contamination are presented along with their fatty acid (FA) composition to provide further elements for a risk/benefit balance of fish consumption to be assessed. The 29 most consumed marine fish species were collected in four metropolitan French coastal areas in 2004 to constitute composite samples. Geographical differences in terms of consumed species and contamination level were taken into account. Three hundred and eighty-seven composite samples corresponding to 16 freshwater fish species collected between 2008 and 2010 in the six major French rivers or their tributaries were selected among the French national agency for water and aquatic environments freshwater fish sample library. The raw edible parts were analyzed for FA composition and PFAA contamination. Results show that freshwater fishes are more contaminated by PFAAs than marine fishes and do not share the same contamination profile. Freshwater fish contamination is mostly driven by perfluorooctane sulfonate (PFOS) (75%), whereas marine fish contamination is split between perfluorooctanoic acid (PFOA) (24%), PFOS (20%), perfluorohexanoic acid (PFHxA) (15%), perfluoropentanoic acid (PFHpA) (11%), and perfluorobutanoic acid (PFBA) (11%). Common carp, pike-perch, European perch, thicklip grey mullet, and common roach presented the most unfavorable balance profile due to their high level of PFAAs and low level of n-3 long-chain polyunsaturated fatty acids (LC-PUFAs). These data could be used, if needed, in an updated opinion on fish consumption that takes into account PFAA contamination.

  2. Diversity of 16S rRNA and dioxygenase genes detected in coal-tar-contaminated site undergoing active bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, M; Khanna, S [NIIT Univ, Neemrana (India). Dept. of Biotechnology & Bioinformation

    2010-04-15

    In order to develop effective bioremediation strategies for polyaromatic hydrocarbons (PAHs) degradation, the composition and metabolic potential of microbial communities need to be better understood, especially in highly PAH contaminated sites in which little information on the cultivation-independent communities is available. Coal-tar-contaminated soil was collected, which consisted of 122-122.5 mg g{sup -1} total extractable PAH compounds. Biodegradation studies with this soil indicated the presence of microbial community that is capable of degrading the model PAH compounds viz naphthalene, phenanthrene and pyrene at 50 ppm each. PCR clone libraries were established from the DNA of the coal-tar-contaminated soil, targeting the 16S rRNA to characterize (I) the microbial communities, (ii) partial gene fragment encoding the Rieske iron sulfur center {alpha}-subunit) common to all PAH dioxygenase enzymes and (iii) {beta}-subunit of dioxygenase. Phylotypes related to Proteobacteria ({Alpha}-, {Epsilon}- and Gammaproteobacteria), Acidobacteria, Actinobacteria, Firmicutes, Gemmatimonadetes and Deinococci were detected in 16S rRNA derived clone libraries. Many of the gene fragment sequences of alpha-subunit and beta-subunit of dioxygenase obtained from the respective clone libraries fell into clades that are distinct from the reference dioxygenase gene sequences. Presence of consensus sequence of the Rieske type (2Fe2S) cluster binding site suggested that these gene fragments encode for {alpha}-subunit of dioxygenase gene. Sequencing of the cloned libraries representing {alpha}-subunit gene fragments (Rf1) and beta-subunit of dioxygenase showed the presence of hitherto unidentified dioxygenase in coal-tar-contaminated soil.

  3. Response of microbial activities and diversity to PAHs contamination at coal tar contaminated land

    Science.gov (United States)

    Zhao, Xiaohui; Sun, Yujiao; Ding, Aizhong; Zhang, Dan; Zhang, Dayi

    2015-04-01

    Coal tar is one of the most hazardous and concerned organic pollutants and the main hazards are polycyclic aromatic hydrocarbons (PAHs). The indigenous microorganisms in soils are capable to degrade PAHs, with essential roles in biochemical process for PAHs natural attenuation. This study investigated 48 soil samples (from 8 depths of 6 boreholes) in Beijing coking and chemistry plant (China) and revealed the correlation between PAHs contamination, soil enzyme activities and microbial community structure, by 16S rRNA denaturing gradient gel electrophoresis (DGGE). At the site, the key contaminants were identified as naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene and anthracene, and the total PAHs concentration ranged from 0.1 to 923.9 mg/kg dry soil. The total PAHs contamination level was positively correlated (pcatalase activities (0.554-6.230 mL 0.02 M KMnO4/g•h) and dehydrogenase activities (1.9-30.4 TF μg/g•h soil), showing the significant response of microbial population and degrading functions to the organic contamination in soils. The PAHs contamination stimulated the PAHs degrading microbes and promoted their biochemical roles in situ. The positive relationship between bacteria count and dehydrogenase activities (p<0.05) suggested the dominancy of PAHs degrading bacteria in the microbial community. More interestingly, the microbial community deterioration was uncovered via the decline of microbial biodiversity (richness from 16S rRNA DGGE) against total PAHs concentration (p<0.05). Our research described the spatial profiles of PAHs contamination and soil microbial functions at the PAHs heavily contaminated sites, offering deeper understanding on the roles of indigenous microbial community in natural attenuation process.

  4. Development and application of an innovative expert decision support system to manage sediments and to assess environmental risk in freshwater ecosystems.

    Science.gov (United States)

    Dagnino, Alessandro; Bo, Tiziano; Copetta, Andrea; Fenoglio, Stefano; Oliveri, Caterina; Bencivenga, Mauro; Felli, Angelo; Viarengo, Aldo

    2013-10-01

    With the aim of supporting decision makers to manage contamination in freshwater environments, an innovative expert decision support system (EDSS) was developed. The EDSS was applied in a sediment quality assessment along the Bormida river (NW, Italy) which has been heavily contaminated by an upstream industrial site for more than a century. Sampling sites were classified by means of comparing chemical concentrations with effect-based target values (threshold and probable effect concentrations). The level of each contaminant and the combined toxic pressure were used to rank sites into three categories: (i) uncontaminated (8 sites), (ii) mildly contaminated (4) and (iii) heavily contaminated (19). In heavily contaminated sediments, an environmental risk index (EnvRI) was determined by means of integrating chemical data with ecotoxicological and ecological parameters (triad approach). In addition a sediment risk index (SedRI) was computed from combining chemical and ecotoxicological data. Eight sites exhibited EnvRI values ≥0.25, the safety threshold level (range of EnvRI values: 0.14-0.31) whereas SedRI exceeded the safety threshold level at 6 sites (range of SedRI values: 0.16-0.36). At sites classified as mildly contaminated, sublethal biomarkers were integrated with chemical data into a biological vulnerability index (BVI), which exceeded the safety threshold level at one site (BVI value: 0.28). Finally, potential human risk was assessed in selected stations (11 sites) by integrating genotoxicity biomarkers (GTI index falling in the range 0.00-0.53). General conclusions drawn from the EDSS data include: (i) in sites classified as heavily contaminated, only a few exhibited some significant, yet limited, effects on biodiversity; (ii) restrictions in re-using sediments from heavily contaminated sites found little support in ecotoxicological data; (iii) in the majority of the sites classified as mildly contaminated, tested organisms exhibited low response levels

  5. Dissimilatory Sb(V) reduction by microorganisms isolated from Sb-contaminated sediment

    Science.gov (United States)

    Dovick, M. A.; Kulp, T. R.

    2013-12-01

    Mining and smelting are major sources of trace metal contamination in freshwater systems. Arsenic (As) is a common contaminant derived from certain mining operations and is a known toxic metalloid and carcinogen. Antimony (Sb) is listed as a pollutant of priority interest by the EPA and is presumed to share similar geochemical and toxicological properties with arsenic. Both elements can occur in four different oxidation states (V, III, 0, and -III) under naturally occurring conditions. In aqueous solutions As(V) and Sb(V) predominate in oxygenated surface waters whereas As(III) and Sb(III) are stable in anoxic settings. Numerous studies have examined microbiological redox pathways that utilize As(V) as a terminal electron acceptor for anaerobic respiration, however there have been few studies on microbial mechanisms that may affect the biogeochemical cycling of Sb in the environment. Here we report bacterial reduction of Sb(V) to Sb(III) in anoxic enrichment cultures and bacterial isolates grown from sediment collected from an Sb contaminated pond at a mine tailings site in Idaho (total pond water Sb concentration = 235.2 +/- 136.3 ug/L). Anaerobic sediment microcosms (40 mL) were established in artificial freshwater mineral salt medium, amended with millimolar concentrations of Sb(V), acetate or lactate, and incubated at 27°C for several days. Antimony(V), lactate, and acetate concentrations were monitored during incubation by High Performance Liquid Chromatography (HPLC) and Ion Chromatography (IC). Live sediment microcosms reduced millimolar amendments of Sb(V) to Sb(III) coupled to the oxidation of acetate and lactate, while no activity occurred in killed controls. Enrichment cultures were established by serially diluting Sb(V)-reducing microcosms in mineral salt medium with Sb(V) and acetate, and a Sb(V)-reducing bacterial strain was isolated by plating on anaerobic agar plates amended with millimolar Sb(V) and acetate. Direct cell counting demonstrated that

  6. Evaluation of natural attenuation processes in the groundwater of a tar oil contaminated site: development of a monitoring network

    International Nuclear Information System (INIS)

    Borke, P.; Husers, N.; Werner, P.; Leibenath, C.

    2005-01-01

    Tar oil is a complex mixture of mainly aromatic hydrocarbons. It is found in the subsurface of manufactured gas plants (MGP), coking plants or wood preserving facilities. The transportation into the soil and groundwater stands for a severe contamination. This is due to the physico-chemical properties of the DNAPL (dense non aqueous phase liquid) and its mobility in the soil and aquifer system. Additionally most of the contaminants show a low biological degradability and solubility under in situ conditions. Therefore it is known as a long term source of contamination. Nevertheless, natural attenuation (NA) processes are detectable at tar oil contaminated sites. In the thematic network two of the German funding priority KORA (http://www.natural-attenuation.de) these processes are matter of investigation. Four typical contaminated sites were chosen to evaluate under which circumstances monitored natural attenuation (MNA) is applicable. Furthermore enhanced natural attenuation questions are examined. The design of monitoring networks at tar oil contaminated sites plays a significant role in gaining field evidence for natural attenuation as well as documenting the efficiency of the attenuation processes and evaluating the matching of performance goals. Well designed monitoring networks include the placement of monitoring wells in 3D so that 3D flow path, mass balances and an estimation of mass flux can be monitored. As an example the history of the monitoring network of a wood preserving facility is shown. Starting from a risk assessment network to a network for MNA is presented. In this case for example especially the determination of the groundwater flow direction in time and space is connected to the number of observation wells and their location. Moreover in the beginning the observation wells were located according to the assumed centerline of the plume. Because of the variability of the groundwater flow direction and the need to determine mass flux a control plane

  7. Development and application of freshwater sediment-toxicity benchmarks for currently used pesticides

    Science.gov (United States)

    Nowell, Lisa H.; Norman, Julia E.; Ingersoll, Christopher G.; Moran, Patrick W.

    2016-01-01

    Sediment-toxicity benchmarks are needed to interpret the biological significance of currently used pesticides detected in whole sediments. Two types of freshwater sediment benchmarks for pesticides were developed using spiked-sediment bioassay (SSB) data from the literature. These benchmarks can be used to interpret sediment-toxicity data or to assess the potential toxicity of pesticides in whole sediment. The Likely Effect Benchmark (LEB) defines a pesticide concentration in whole sediment above which there is a high probability of adverse effects on benthic invertebrates, and the Threshold Effect Benchmark (TEB) defines a concentration below which adverse effects are unlikely. For compounds without available SSBs, benchmarks were estimated using equilibrium partitioning (EqP). When a sediment sample contains a pesticide mixture, benchmark quotients can be summed for all detected pesticides to produce an indicator of potential toxicity for that mixture. Benchmarks were developed for 48 pesticide compounds using SSB data and 81 compounds using the EqP approach. In an example application, data for pesticides measured in sediment from 197 streams across the United States were evaluated using these benchmarks, and compared to measured toxicity from whole-sediment toxicity tests conducted with the amphipod Hyalella azteca (28-d exposures) and the midge Chironomus dilutus (10-d exposures). Amphipod survival, weight, and biomass were significantly and inversely related to summed benchmark quotients, whereas midge survival, weight, and biomass showed no relationship to benchmarks. Samples with LEB exceedances were rare (n = 3), but all were toxic to amphipods (i.e., significantly different from control). Significant toxicity to amphipods was observed for 72% of samples exceeding one or more TEBs, compared to 18% of samples below all TEBs. Factors affecting toxicity below TEBs may include the presence of contaminants other than pesticides, physical

  8. Chronic toxicity of nickel-spiked freshwater sediments: variation in toxicity among eight invertebrate taxa and eight sediments

    Science.gov (United States)

    Besser, John M.; Brumbaugh, William G.; Ingersoll, Christopher G.; Ivey, Chris D.; Kunz, James L.; Kemble, Nile E.; Schlekat, Christian E.; Garman, Emily R.

    2013-01-01

    This study evaluated the chronic toxicity of Ni-spiked freshwater sediments to benthic invertebrates. A 2-step spiking procedure (spiking and sediment dilution) and a 2-stage equilibration period (10 wk anaerobic and 1 wk aerobic) were used to spike 8 freshwater sediments with wide ranges of acid-volatile sulfide (AVS; 0.94–38 µmol/g) and total organic carbon (TOC; 0.42–10%). Chronic sediment toxicity tests were conducted with 8 invertebrates (Hyalella azteca, Gammarus pseudolimnaeus, Chironomus riparius, Chironomus dilutus, Hexagenia sp., Lumbriculus variegatus, Tubifex tubifex, and Lampsilis siliquoidea) in 2 spiked sediments. Nickel toxicity thresholds estimated from species-sensitivity distributions were 97 µg/g and 752 µg/g (total recoverable Ni; dry wt basis) for sediments with low and high concentrations of AVS and TOC, respectively. Sensitive species were tested with 6 additional sediments. The 20% effect concentrations (EC20s) for Hyalella and Gammarus, but not Hexagenia, were consistent with US Environmental Protection Agency benchmarks based on Ni in porewater and in simultaneously extracted metals (SEM) normalized to AVS and TOC. For Hexagenia, sediment EC20s increased at less than an equimolar basis with increased AVS, and toxicity occurred in several sediments with Ni concentrations in SEM less than AVS. The authors hypothesize that circulation of oxygenated water by Hexagenia led to oxidation of AVS in burrows, creating microenvironments with high Ni exposure. Despite these unexpected results, a strong relationship between Hexagenia EC20s and AVS could provide a basis for conservative site-specific sediment quality guidelines for Ni.

  9. Characterizing toxicity of metal-contaminated sediments from mining areas

    International Nuclear Information System (INIS)

    Besser, John M.; Brumbaugh, William G.; Ingersoll, Christopher G.

    2015-01-01

    Highlights: • We review methods for testing toxicity of sediments affected by metals. • Toxicity testing provides site-specific assessment of impacts on resident biota. • Goals are to document extent of toxicity and associations with metal exposure. • Need to characterize bioavailability of metals in sediment and pore water. • Toxicity data is basis for guidelines used to predict hazards of metal toxicity. - Abstract: This paper reviews methods for testing the toxicity of metals associated with freshwater sediments, linking toxic effects with metal exposure and bioavailability, and developing sediment quality guidelines. The most broadly applicable approach for characterizing metal toxicity is whole-sediment toxicity testing, which attempts to simulate natural exposure conditions in the laboratory. Standard methods for whole-sediment testing can be adapted to test a wide variety of taxa. Chronic sediment tests that characterize effects on multiple endpoints (e.g., survival, growth, and reproduction) can be highly sensitive indicators of adverse effects on resident invertebrate taxa. Methods for testing of aqueous phases (pore water, overlying water, or elutriates) are used less frequently. Analysis of sediment toxicity data focuses on statistical comparisons between responses in sediments from the study area and responses in one or more uncontaminated reference sediments. For large or complex study areas, a greater number of reference sediments is recommended to reliably define the normal range of responses in uncontaminated sediments – the ‘reference envelope’. Data on metal concentrations and effects on test organisms across a gradient of contamination may allow development of concentration-response models, which estimate metal concentrations associated with specified levels of toxic effects (e.g. 20% effect concentration or EC20). Comparisons of toxic effects in laboratory tests with measures of impacts on resident benthic invertebrate

  10. Development and application of freshwater sediment-toxicity benchmarks for currently used pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Nowell, Lisa H., E-mail: lhnowell@usgs.gov [U.S. Geological Survey, California Water Science Center, Placer Hall, 6000 J Street, Sacramento, CA 95819 (United States); Norman, Julia E., E-mail: jnorman@usgs.gov [U.S. Geological Survey, Oregon Water Science Center, 2130 SW 5" t" h Avenue, Portland, OR 97201 (United States); Ingersoll, Christopher G., E-mail: cingersoll@usgs.gov [U.S. Geological Survey, Columbia Environmental Research Center, 4200 New Haven Road, Columbia, MO 65021 (United States); Moran, Patrick W., E-mail: pwmoran@usgs.gov [U.S. Geological Survey, Washington Water Science Center, 934 Broadway, Suite 300, Tacoma, WA 98402 (United States)

    2016-04-15

    Sediment-toxicity benchmarks are needed to interpret the biological significance of currently used pesticides detected in whole sediments. Two types of freshwater sediment benchmarks for pesticides were developed using spiked-sediment bioassay (SSB) data from the literature. These benchmarks can be used to interpret sediment-toxicity data or to assess the potential toxicity of pesticides in whole sediment. The Likely Effect Benchmark (LEB) defines a pesticide concentration in whole sediment above which there is a high probability of adverse effects on benthic invertebrates, and the Threshold Effect Benchmark (TEB) defines a concentration below which adverse effects are unlikely. For compounds without available SSBs, benchmarks were estimated using equilibrium partitioning (EqP). When a sediment sample contains a pesticide mixture, benchmark quotients can be summed for all detected pesticides to produce an indicator of potential toxicity for that mixture. Benchmarks were developed for 48 pesticide compounds using SSB data and 81 compounds using the EqP approach. In an example application, data for pesticides measured in sediment from 197 streams across the United States were evaluated using these benchmarks, and compared to measured toxicity from whole-sediment toxicity tests conducted with the amphipod Hyalella azteca (28-d exposures) and the midge Chironomus dilutus (10-d exposures). Amphipod survival, weight, and biomass were significantly and inversely related to summed benchmark quotients, whereas midge survival, weight, and biomass showed no relationship to benchmarks. Samples with LEB exceedances were rare (n = 3), but all were toxic to amphipods (i.e., significantly different from control). Significant toxicity to amphipods was observed for 72% of samples exceeding one or more TEBs, compared to 18% of samples below all TEBs. Factors affecting toxicity below TEBs may include the presence of contaminants other than pesticides, physical/chemical characteristics

  11. Development and application of freshwater sediment-toxicity benchmarks for currently used pesticides

    International Nuclear Information System (INIS)

    Nowell, Lisa H.; Norman, Julia E.; Ingersoll, Christopher G.; Moran, Patrick W.

    2016-01-01

    Sediment-toxicity benchmarks are needed to interpret the biological significance of currently used pesticides detected in whole sediments. Two types of freshwater sediment benchmarks for pesticides were developed using spiked-sediment bioassay (SSB) data from the literature. These benchmarks can be used to interpret sediment-toxicity data or to assess the potential toxicity of pesticides in whole sediment. The Likely Effect Benchmark (LEB) defines a pesticide concentration in whole sediment above which there is a high probability of adverse effects on benthic invertebrates, and the Threshold Effect Benchmark (TEB) defines a concentration below which adverse effects are unlikely. For compounds without available SSBs, benchmarks were estimated using equilibrium partitioning (EqP). When a sediment sample contains a pesticide mixture, benchmark quotients can be summed for all detected pesticides to produce an indicator of potential toxicity for that mixture. Benchmarks were developed for 48 pesticide compounds using SSB data and 81 compounds using the EqP approach. In an example application, data for pesticides measured in sediment from 197 streams across the United States were evaluated using these benchmarks, and compared to measured toxicity from whole-sediment toxicity tests conducted with the amphipod Hyalella azteca (28-d exposures) and the midge Chironomus dilutus (10-d exposures). Amphipod survival, weight, and biomass were significantly and inversely related to summed benchmark quotients, whereas midge survival, weight, and biomass showed no relationship to benchmarks. Samples with LEB exceedances were rare (n = 3), but all were toxic to amphipods (i.e., significantly different from control). Significant toxicity to amphipods was observed for 72% of samples exceeding one or more TEBs, compared to 18% of samples below all TEBs. Factors affecting toxicity below TEBs may include the presence of contaminants other than pesticides, physical/chemical characteristics

  12. Comparative food-chain behavior and distribution of actinide elements in and around a contaminated fresh-water pond

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.; Trabalka, J.R.; Bogle, M.A.

    1981-01-01

    The bioaccumulation of 233 234 U, 238 U, 238 Pu, 239 240 Pu, 241 Am, and 244 Cm in both native and introduced biota was studied at Pond 3513, a former low-level radioactive waste settling basin at Oak Ridge National Laboratory. This system, which was decommissioned in 1976 after more than 30 years use, contains approximately 5 Ci of 239 240 Pu; inventories of other actinide isotopes are considerably less. Significantly higher concentrations of actinides in fish that were allowed access to sediments indicated that sedimentary particulates may be the primary source of transuranics to biota in shallow fresh-water ecosystems. Our study determined habitat, in particular the degree of association of an organism with the sediment-water interface, to be the primary factor in controlling transuranic concentrations in aquatic biota. In most of the biological samples analyzed, excluding samples suspected of being contaminated by sediment, 241 Am/ 239 Pu, 244 Cm/ 239 Pu, and 238 U/ 239 Pu ratios were greater than the respective ratio in sediment while 233 234 U/ 238 U, and 239 240 Pu/ 238 Pu ratios were not different from the respective ratios in sediment. The relative uptake of actinides from contaminated sediment by aquatic and terrestrial biota at this site was U > Cm greater than or equal to Am > Pu. The relative extractability of actinides from shoreline sediment was U > Cm approx. = Am > Pu; we also observed the same relative ranking for sediment-water exchange in situ. Concentrations of transuranics in water, terrestrial vegetation, and vertebrate carcasses were less than 10% of the recommended public exposure maximum permissible concentration (MPC) of the ICRP

  13. Toxicity of lead-contaminated sediment to mute swans

    Science.gov (United States)

    Day, D.D.; Beyer, W.N.; Hoffman, D.J.; Morton, Alexandra; Sileo, L.; Audet, D.J.; Ottinger, M.A.

    2003-01-01

    Most ecotoxicological risk assessments of wildlife emphasize contaminant exposure through ingestion of food and water. However, the role of incidental ingestion of sediment-bound contaminants has not been adequately appreciated in these assessments. This study evaluates the toxicological consequences of contamination of sediments with metals from hard-rock mining and smelting activities. Lead-contaminated sediments collected from the Coeur d'Alene River Basin in Idaho were combined with either a commercial avian maintenance diet or ground rice and fed to captive mute swans (Cygnus olor) for 6 weeks. Experimental treatments consisted of maintenance or rice diets containing 0, 12 (no rice group), or 24% highly contaminated (3,950 ug/g lead) sediment or 24% reference (9.7 ug/g lead) sediment. Although none of the swans died, the group fed a rice diet containing 24% lead-contaminated sediment were the most severely affected, experiencing a 24% decrease in mean body weight, including three birds that became emaciated. All birds in this treatment group had nephrosis; abnormally dark, viscous bile; and significant (p < 0.05) reductions in hematocrit and hemoglobin concentrations compared to their pretreatment levels. This group also had the greatest mean concentrations of lead in blood (3.2 ug/g), brain (2.2 ug/g), and liver (8.5 ug/g). These birds had significant (alpha = 0.05) increases in mean plasma alanine aminotransferase activity, cholesterol, and uric acid concentrations and decreased plasma triglyceride concentrations compared to all other treatment groups. After 14 days of exposure, mean protoporphyrin concentrations increased substantially, and mean delta-aminolevulinic acid dehydratase activity decreased by more than 95% in all groups fed diets containing highly contaminated sediments. All swans fed diets that contained 24% lead-contaminated sediment had renal acid-fast intranuclear inclusion bodies, which are diagnostic of lead poisoning in waterfowl. Body

  14. Contamination of Detained Sediment in Sustainable Urban Drainage Systems

    Directory of Open Access Journals (Sweden)

    Deonie Allen

    2017-05-01

    Full Text Available Adsorption is a key water pollution remediation measure used to achieve stormwater quality improvement in Sustainable urban Drainage Systems (SuDS. The level of contamination of detained sediment within SuDS assets is not well documented, with published investigations limited to specific contaminant occurrence in ponds, wetlands or infiltration devices (bioretention cells and generally focused on solute or suspended sediment. Guidance on contamination threshold levels and potential deposited sediment contamination information is not included in current UK SuDS design or maintenance guidance, primarily due to a lack of evidence and understanding. There is a need to understand possible deposited sediment contamination levels in SuDS, specifically in relation to sediment removal maintenance activities and potential impact on receiving waterways of conveyed sediment. Thus, the objective of the research presented herein was to identify what major elements and trace metals were observable in (the investigated SuDS assets detained sediment, the concentration of these major elements and trace metals and whether they met/surpassed ecotoxicity or contaminated land thresholds. The research presented here provides evidence of investigated SuDS sediment major element and trace metal levels to help inform guidance and maintenance needs, and presents a new methodology to identify the general cause (anthropocentric land use and extent of detained SuDS fine urban sediment contamination through use of a contamination matrix.

  15. Effects of clay minerals and organic matter in formulated sediments on the bioavailability of sediment-associated uranium to the freshwater midge, Chironomus dilutus

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Sarah E., E-mail: sarah.crawford@usask.ca [Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3 (Canada); Liber, Karsten, E-mail: karsten.liber@usask.ca [Toxicology Centre, University of Saskatchewan, 44 Campus Drive, Saskatoon, SK S7N 5B3 (Canada); School of Environment and Sustainability, 117 Science Place, University of Saskatchewan, Saskatoon, SK S7N 5C8 (Canada); Institute of Loess Plateau, 92 Wucheng Road, Shanxi University, Taiyuan, Shanxi 030006 (China)

    2015-11-01

    It is well established that bioavailability influences metal toxicity in aquatic ecosystems. However, the factors and mechanisms that influence uranium (U) bioavailability and toxicity in sediment have not been thoroughly evaluated, despite evidence that suggests different sediment components can influence the sorption and interaction of some metals. Given that dissolved U is generally accepted as being the primary bioavailable fraction of U, it is hypothesized that adsorption and interaction of U with different sediment components will influence the bioavailability of U in sediment. We investigated the effects of key sediment physicochemical properties on the bioavailability of U to a model freshwater benthic invertebrate, Chironomus dilutus. Several 10-day spiked sediment bioaccumulation experiments were performed, exposing C. dilutus larvae to a variety of formulated sediments spiked with different concentrations of U (5, 50 and/or 200 mg U/kg d.w.). Mean accumulation of U in C. dilutus larvae decreased significantly from 1195 to 10 mg U/kg d.w. as kaolin clay content increased from 0% to 60% in sediment spiked with 50 mg U/kg d.w. Similarly, higher organic matter content also resulted in a significant reduction of U bioaccumulation in C. dilutus larvae, indicating a reduction in U bioavailability. Concentrations of U in both the overlying water and sediment pore water displayed a strong positive relationship to U bioaccumulation in C. dilutus larvae (r{sup 2} = 0.77, p < 0.001 and r{sup 2} = 0.57, p < 0.001, respectively) for all experiments, while total U concentrations in the sediment had a poor relationship to U bioaccumulation (r{sup 2} = 0.10, p = 0.028). Results from this research confirm that sediment clay and organic matter content play a significant role in altering U bioavailability, which is important in informing risk assessments of U contaminated sites and in the development of site-specific sediment quality guidelines for U. - Highlights: • We

  16. The filter feeder Dreissena polymorpha affects nutrient, silicon, and metal(loid) mobilization from freshwater sediments.

    Science.gov (United States)

    Schaller, Jörg; Planer-Friedrich, Britta

    2017-05-01

    Organic sediments in aquatic ecosystems are well known sinks for nutrients, silicon, and metal(loid)s. Organic matter-consuming organisms like invertebrate shredders, grazers, and bioturbators significantly affect element fixation or remobilization by changing redox conditions or binding properties of organic sediments. Little is known about the effect of filter feeders, like the zebra mussel Dreissena polymorpha, an invasive organism in North American and European freshwater ecosystems. A laboratory batch experiment exposing D. polymorpha (∼1200 organisms per m 2 ) to organic sediment from a site contaminated with arsenic, copper, lead, and uranium revealed a significant uptake and accumulation of arsenic, copper, iron, and especially uranium both into the soft body tissues and the seashell. This is in line with previous observations of metal(loid) accumulation from biomonitoring studies. Regarding its environmental impact, D. polymorpha significantly contributed to mobilization of silicon, iron, phosphorus, arsenic, and copper and to immobilization of uranium (p < 0.001), probably driven by redox conditions, microbial activity within the gut system, or active control of element homeostasis. No net mobilization or immobilization was observed for zinc and lead, because of their low mobility at the prevailing pH of 7.5-8.5. The present results suggest that D. polymorpha can both ameliorate (nutrient mobilization, immobilization of toxicants mobile under oxic conditions) or aggravate negative effects (mobilization of toxicants mobile under reducing conditions) in ecosystems. Relating the results of the present study to observed population densities in natural freshwater ecosystems suggests a significant influence of D. polymorpha on element cycling and needs to be considered in future studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Temporal and Spatial Dynamics of Sediment Anaerobic Ammonium Oxidation (Anammox) Bacteria in Freshwater Lakes.

    Science.gov (United States)

    Yang, Yuyin; Dai, Yu; Li, Ningning; Li, Bingxin; Xie, Shuguang; Liu, Yong

    2017-02-01

    Anaerobic ammonium-oxidizing (anammox) process can play an important role in freshwater nitrogen cycle. However, the distribution of anammox bacteria in freshwater lake and the associated environmental factors remain essentially unclear. The present study investigated the temporal and spatial dynamics of sediment anammox bacterial populations in eutrotrophic Dianchi Lake and mesotrophic Erhai Lake on the Yunnan Plateau (southwestern China). The remarkable spatial change of anammox bacterial abundance was found in Dianchi Lake, while the relatively slight spatial shift occurred in Erhai Lake. Dianchi Lake had greater anammox bacterial abundance than Erhai Lake. In both Dianchi Lake and Erhai Lake, anammox bacteria were much more abundant in summer than in spring. Anammox bacterial community richness, diversity, and structure in these two freshwater lakes were subjected to temporal and spatial variations. Sediment anammox bacterial communities in Dianchi Lake and Erhai Lake were dominated by Candidatus Brocadia and a novel phylotype followed by Candidatus Kuenenia; however, these two lakes had distinct anammox bacterial community structure. In addition, trophic status determined sediment anammox bacterial community structure.

  18. Isolation and characterization of acetate-utilizing anaerobes from a freshwater sediment

    NARCIS (Netherlands)

    Scholten, J.C.M.; Stams, A.J.M.

    2000-01-01

    Acetate-degrading anaerobic microorganisms in freshwater sediment were quantified by the most probable number technique. From the highest dilutions a methanogenic, a sulfate-reducing, and a nitrate-reducing microorganism were isolated with acetate as substrate. The methanogen (culture AMPB-Zg) was

  19. The trace element analysis in freshwater fish species, water and sediment in Iyidere stream (Rize-Turkey).

    Science.gov (United States)

    Verep, Bulent; Mutlu, Cengiz; Apaydin, Gokhan; Cevik, Ugur

    2012-07-15

    Many environmental problems like dam construction, agricultural debris, flooding and industrial establishments threaten Iyidere stream (Rize, Turkey) on the southeastern coast of the Black Sea (Turkey). The trace element concentrations in water, fish and sediments in lyidere stream (Rize, Turkey) were investigated in this study. The concentration of six different elements in ten freshwater fish species and sediment was determined using energy dispersive X-ray fluorescence method. A radioisotope excited X-ray fluorescence analysis using the method of multiple standard addition is applied for the elemental analysis of fish and sediments. Water samples for trace metals were analyzed using standard spectrophotometry methods. A qualitative analysis of spectral peaks showed that ten different freshwater fish samples (Chondrostoma colchicum, Chalcalburnus chalcoides, Salmo trutta labrax, Alburnoides bipunctatus, Leuciscus cephalus, Barbus taurus escherichia, Capoeta tinca, Neogobius kessleri, Rutilus frisii, Lampetra lanceolata) and sediment contained phosphorus (P), sulphur (S), chlorine (Cl), potassium (K), calcium (Ca) and titanium (Ti). Heavy metals as toxic elements for biota (Pb, Cd, Hg, Zn and Mn etc.) were not detected in fish, water and sediments. Thus, It can be declared that freshwater fish of Iyidere does not contains health risks for consumers in terms of metal pollution.

  20. Preparation and characterization of nickel-spiked freshwater sediments for toxicity tests: toward more environmentally realistic nickel partitioning

    Science.gov (United States)

    Brumbaugh, William G.; Besser, John M.; Ingersoll, Christopher G.; May, Thomas W.; Ivey, Chris D.; Schlekat, Christian E.; Garman, Emily R.

    2013-01-01

    Two spiking methods were compared and nickel (Ni) partitioning was evaluated during a series of toxicity tests with 8 different freshwater sediments having a range of physicochemical characteristics. A 2-step spiking approach with immediate pH adjustment by addition of NaOH at a 2:1 molar ratio to the spiked Ni was effective in producing consistent pH and other chemical characteristics across a range of Ni spiking levels. When Ni was spiked into sediment having a high acid-volatile sulfide and organic matter content, a total equilibration period of at least 10 wk was needed to stabilize Ni partitioning. However, highest spiking levels evidently exceeded sediment binding capacities; therefore, a 7-d equilibration in toxicity test chambers and 8 volume-additions/d of aerobic overlying water were used to avoid unrealistic Ni partitioning during toxicity testing. The 7-d pretest equilibration allowed excess spiked Ni and other ions from pH adjustment to diffuse from sediment porewater and promoted development of an environmentally relevant, 0.5- to 1-cm oxic/suboxic sediment layer in the test chambers. Among the 8 different spiked sediments, the logarithm of sediment/porewater distribution coefficient values (log Kd) for Ni during the toxicity tests ranged from 3.5 to 4.5. These Kd values closely match the range of values reported for various field Ni-contaminated sediments, indicating that testing conditions with our spiked sediments were environmentally realistic.

  1. Characterization of acid tars

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, Sunday A., E-mail: sunday.leonard@ucl.ac.uk [Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT (United Kingdom); Stegemann, Julia A. [Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT (United Kingdom); Roy, Amitava [J. Bennett Johnston, Sr., Centre for Advance Microstructures and Devices (CAMD), 6980 Jefferson Highway, Louisiana State University, Baton Rouge, LA, 70806 (United States)

    2010-03-15

    Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

  2. Characterization of acid tars

    International Nuclear Information System (INIS)

    Leonard, Sunday A.; Stegemann, Julia A.; Roy, Amitava

    2010-01-01

    Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain.

  3. Spatial and seasonal variations of Acid Volatile Sulfide (AVS) and Simultaneously Extracted Metals (SEM) in Dutch marine and freshwater sediments

    NARCIS (Netherlands)

    Hoop MAGT van den; Hollander HA den; Kerdijk HN; LAC; ECO; Delft Hydraulics

    1995-01-01

    Within the framework of the project Exposure Assessment, Acid Volatile Sulfide (AVS) and Simultaneously Extracted Metal (SEM) contents of Dutch marine and freshwater sediments were determined. For the present set of fifteen marine and six freshwater sediments AVS levels vary between non-detectable

  4. Diversity of sulfur-cycle prokaryotes in freshwater lake sediments investigated using aprA as the functional marker gene.

    Science.gov (United States)

    Watanabe, Tomohiro; Kojima, Hisaya; Takano, Yoshinori; Fukui, Manabu

    2013-09-01

    The diversity of sulfate-reducing prokaryotes (SRPs) and sulfur-oxidizing prokaryotes (SOPs) in freshwater lake ecosystems was investigated by cloning and sequencing of the aprA gene, which encodes for a key enzyme in dissimilatory sulfate reduction and sulfur oxidation. To understand their diversity better, the spatial distribution of aprA genes was investigated in sediments collected from six geographically distant lakes in Antarctica and Japan, including a hypersaline lake for comparison. The microbial community compositions of freshwater sediments and a hypersaline sediment showed notable differences. The clones affiliated with Desulfobacteraceae and Desulfobulbaceae were frequently detected in all freshwater lake sediments. The SOP community was mainly composed of four major phylogenetic groups. One of them formed a monophyletic cluster with a sulfur-oxidizing betaproteobacterium, Sulfuricella denitrificans, but the others were not assigned to specific genera. In addition, the AprA sequences, which were not clearly affiliated to either SRP or SOP lineages, dominated the libraries from four freshwater lake sediments. The results showed the wide distribution of some sulfur-cycle prokaryotes across geographical distances and supported the idea that metabolic flexibility is an important feature for SRP survival in low-sulfate environments. Copyright © 2013 Elsevier GmbH. All rights reserved.

  5. Mixture design and treatment methods for recycling contaminated sediment

    International Nuclear Information System (INIS)

    Wang, Lei; Kwok, June S.H.; Tsang, Daniel C.W.; Poon, Chi-Sun

    2015-01-01

    Graphical abstract: - Highlights: • Contaminated sediment can be recycled as fill material for site formation. • Thermal pretreatment of sediment permits non-load-bearing block application. • CO 2 curing enhances strength and reduces carbon footprint. • Inclusion of granular wastes reinforces the solidified sediment matrix. • Sediment blocks are useful resources for construction use. - Abstract: Conventional marine disposal of contaminated sediment presents significant financial and environmental burden. This study aimed to recycle the contaminated sediment by assessing the roles and integration of binder formulation, sediment pretreatment, curing method, and waste inclusion in stabilization/solidification. The results demonstrated that the 28-d compressive strength of sediment blocks produced with coal fly ash and lime partially replacing cement at a binder-to-sediment ratio of 3:7 could be used as fill materials for construction. The X-ray diffraction analysis revealed that hydration products (calcium hydroxide) were difficult to form at high sediment content. Thermal pretreatment of sediment removed 90% of indigenous organic matter, significantly increased the compressive strength, and enabled reuse as non-load-bearing masonry units. Besides, 2-h CO 2 curing accelerated early-stage carbonation inside the porous structure, sequestered 5.6% of CO 2 (by weight) in the sediment blocks, and acquired strength comparable to 7-d curing. Thermogravimetric analysis indicated substantial weight loss corresponding to decomposition of poorly and well crystalline calcium carbonate. Moreover, partial replacement of contaminated sediment by various granular waste materials notably augmented the strength of sediment blocks. The metal leachability of sediment blocks was minimal and acceptable for reuse. These results suggest that contaminated sediment should be viewed as useful resources

  6. Mixture design and treatment methods for recycling contaminated sediment

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lei; Kwok, June S.H.; Tsang, Daniel C.W., E-mail: dan.tsang@polyu.edu.hk; Poon, Chi-Sun

    2015-02-11

    Graphical abstract: - Highlights: • Contaminated sediment can be recycled as fill material for site formation. • Thermal pretreatment of sediment permits non-load-bearing block application. • CO{sub 2} curing enhances strength and reduces carbon footprint. • Inclusion of granular wastes reinforces the solidified sediment matrix. • Sediment blocks are useful resources for construction use. - Abstract: Conventional marine disposal of contaminated sediment presents significant financial and environmental burden. This study aimed to recycle the contaminated sediment by assessing the roles and integration of binder formulation, sediment pretreatment, curing method, and waste inclusion in stabilization/solidification. The results demonstrated that the 28-d compressive strength of sediment blocks produced with coal fly ash and lime partially replacing cement at a binder-to-sediment ratio of 3:7 could be used as fill materials for construction. The X-ray diffraction analysis revealed that hydration products (calcium hydroxide) were difficult to form at high sediment content. Thermal pretreatment of sediment removed 90% of indigenous organic matter, significantly increased the compressive strength, and enabled reuse as non-load-bearing masonry units. Besides, 2-h CO{sub 2} curing accelerated early-stage carbonation inside the porous structure, sequestered 5.6% of CO{sub 2} (by weight) in the sediment blocks, and acquired strength comparable to 7-d curing. Thermogravimetric analysis indicated substantial weight loss corresponding to decomposition of poorly and well crystalline calcium carbonate. Moreover, partial replacement of contaminated sediment by various granular waste materials notably augmented the strength of sediment blocks. The metal leachability of sediment blocks was minimal and acceptable for reuse. These results suggest that contaminated sediment should be viewed as useful resources.

  7. Characterization of freshwater mosses as indicators of radioactive contamination; Caracterisation de mousses dulcaquicoles comme indicateurs de contamination radioactive

    Energy Technology Data Exchange (ETDEWEB)

    Beaugelin-Seiller, K

    1994-12-16

    The necessity of indicators of freshwater contamination has developed the interest for aquatic mosses. From a fundamental point of view, studying the influence of some biotic and abiotic factors has permitted to better know the mechanisms of radionuclides accumulation by these bryophytes. From a radioecological point of view, simulating real cases of water contamination has allowed to give results a very interesting representativeness. The use of mosses as bio-indicators was applied for two in situ experiments, the results of which have been interpreted from those obtained in laboratory. Finally, an approach by a mathematical model has showed that it is possible to have, in a middle term, an evaluation tool of freshwater contamination, based on the radionuclides concentrations measured in aquatic mosses. (author). refs., 57 figs., 24 tabs.

  8. Bioavailability of sediment-bound contaminants to marine organisms

    Energy Technology Data Exchange (ETDEWEB)

    Brown, B. [Battelle/Marine Sciences Lab., Sequim, WA (United States)]|[Colby Coll., Waterville, ME (United States); Neff, J. [Battelle/Marine Sciences Lab., Sequim, WA (United States)]|[Battelle Ocean Sciences, Duxbury, MA (United States)

    1993-09-01

    The bioavailability of sediment-bound contaminants to marine organisms indicates that there exists a potential for transfer of these contaminants through marine food webs to commercial fisheries products consumed by humans. However, there has been relatively little effort to combine and synthesize data on chemical/biological interactions between benthic animals and seagrasses and the sediments in which they reside on the one hand, and on the chemistry of bioaccumulation on the other. This report provides a conceptual basis for an approach to bioavailability and biomagnification of sediment-bound contaminants that reviews biological and chemical approaches.

  9. Effects of discharge, wind, and tide on sedimentation in a recently restored tidal freshwater wetland

    NARCIS (Netherlands)

    Verschelling, Eelco; van der Deijl, Eveline; van der Perk, Marcel; Sloff, Kees; Middelkoop, Hans

    2017-01-01

    Sediment deposition is one of the key mechanisms to counteract the impact of sea level rise in tidal freshwater wetlands (TFWs). However, information about sediment deposition rates in TFWs is limited, especially for those located in the transition zone between the fluvially dominated and tidally

  10. Human health risk assessment in relation to environmental pollution of two artificial freshwater lakes in The Netherlands.

    OpenAIRE

    Albering, H J; Rila, J P; Moonen, E J; Hoogewerff, J A; Kleinjans, J C

    1999-01-01

    A human health risk assessment has been performed in relation to recreational activities on two artificial freshwater lakes along the river Meuse in The Netherlands. Although the discharges of contaminants into the river Meuse have been reduced in the last decades, which is reflected in decreasing concentrations of pollutants in surface water and suspended matter, the levels in sediments are more persistent. Sediments of the two freshwater lakes appear highly polluted and may pose a health ri...

  11. Effects of discharge, wind, and tide on sedimentation in a recently restored tidal freshwater wetland

    NARCIS (Netherlands)

    Verschelling, Eelco; van der Deijl, Eveline; van der Perk, Marcel; Sloff, C.J.; Middelkoop, Hans

    2017-01-01

    Sediment deposition is one of the key mechanisms to counteract the impact of sea level rise in tidal freshwater wetlands (TFWs). However, information about sediment deposition rates in TFWs is limited, especially for those located in the transition zone between the fluvially dominated and tidally

  12. Role of nitrogen fixation in the autecology of Polaromonas naphthalenivorans in contaminated sediments.

    Science.gov (United States)

    Hanson, Buck T; Yagi, Jane M; Jeon, Che Ok; Madsen, Eugene M

    2012-06-01

    Polaromonas naphthalenivorans strain CJ2 is a Gram-negative betaproteobacterium that was identified, using stable isotope probing in 2003, as a dominant in situ degrader of naphthalene in coal tar-contaminated sediments. The sequenced genome of strain CJ2 revealed several genes conferring nitrogen fixation within a 65.6 kb region of strain CJ2's chromosome that is absent in the genome of its closest sequenced relative Polaromonas sp. strain JS666. Laboratory growth and nitrogenase assays verified that these genes are functional, providing an alternative source of nitrogen in N-free media when using naphthalene or pyruvate as carbon sources. Knowing this, we investigated if nitrogen-fixation activity could be detected in microcosms containing sediments from the field site where strain CJ2 was isolated. Inducing nitrogen limitation with the addition of glucose or naphthalene stimulated nitrogenase activity in amended sediments, as detected using the acetylene reduction assay. With the use of fluorescence microscopy, we screened the microcosm sediments for the presence of active strain CJ2 cells using a dual-labelling approach. When we examined the carbon-amended microcosm sediments stained with both a strain CJ2-specific fluorescent in situ hybridization probe and a polyclonal fluorescently tagged antibody, we were able to detect dual-labelled active cells. In contrast, in sediments that received no carbon addition (showing no nitrogenase activity), no dual-labelled cells were detected. Furthermore, the naphthalene amendment enhanced the proportion of active strain CJ2 cells in the sediment relative to a glucose amendment. Field experiments performed in sediments where strain CJ2 was isolated showed nitrogenase activity in response to dosing with naphthalene. Dual-label fluorescence staining of these sediments showed a fivefold increase in active strain CJ2 in the sediments dosed with naphthalene over those dosed with deionized water. These experiments show that

  13. Nematode communities in contaminated river sediments

    International Nuclear Information System (INIS)

    Heininger, Peter; Hoess, Sebastian; Claus, Evelyn; Pelzer, Juergen; Traunspurger, Walter

    2007-01-01

    Nematode communities of eight sites from three river catchments were investigated in terms of the genera composition, feeding types, and life-history strategists. The sampling sites showed a gradient of anthropogenic contamination with heavy metals and organic pollutants being important factors in differentiating the sites. Nematode community structure was related to sediment pollution and the hydro-morphological structure of the sampling sites. Heavily contaminated sites were characterized by communities with high relative abundances of omnivorous and predacious nematodes (Tobrilus, c-p 3; Mononchus, c-p 4), while sites with low to medium contamination were dominated by bacterivorous nematodes (Monhystera, Daptonema; c-p 2) or suction feeders (Dorylaimus, c-p 4). The relatively high Maturity Index values in the heavily polluted sites were surprising. Nematodes turned out to be a suitable organism group for monitoring sediment quality, with generic composition being the most accurate indicator for assessing differences in nematode community structure. - Nematode community structure of river sediments is related to pollution and site structure

  14. Nematode communities in contaminated river sediments

    Energy Technology Data Exchange (ETDEWEB)

    Heininger, Peter [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56068 Koblenz (Germany); Hoess, Sebastian [Ecossa - Ecological Sediment and Soil Assessment, Thierschstr. 43, 80538 Munich (Germany); Claus, Evelyn [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56068 Koblenz (Germany); Pelzer, Juergen [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56068 Koblenz (Germany); Traunspurger, Walter [University of Bielefeld, Department of Animal Ecology, Morgenbreede 45, 33615 Bielefeld (Germany)]. E-mail: traunspurger@uni-bielefeld.de

    2007-03-15

    Nematode communities of eight sites from three river catchments were investigated in terms of the genera composition, feeding types, and life-history strategists. The sampling sites showed a gradient of anthropogenic contamination with heavy metals and organic pollutants being important factors in differentiating the sites. Nematode community structure was related to sediment pollution and the hydro-morphological structure of the sampling sites. Heavily contaminated sites were characterized by communities with high relative abundances of omnivorous and predacious nematodes (Tobrilus, c-p 3; Mononchus, c-p 4), while sites with low to medium contamination were dominated by bacterivorous nematodes (Monhystera, Daptonema; c-p 2) or suction feeders (Dorylaimus, c-p 4). The relatively high Maturity Index values in the heavily polluted sites were surprising. Nematodes turned out to be a suitable organism group for monitoring sediment quality, with generic composition being the most accurate indicator for assessing differences in nematode community structure. - Nematode community structure of river sediments is related to pollution and site structure.

  15. The biological transport of radionuclides in grassland and freshwater ecosystems

    International Nuclear Information System (INIS)

    Rudge, S.A.

    1989-12-01

    This thesis examines the biological transport of radionuclides through terrestrial and aquatic ecosystems, with particular reference to radiocaesium. The semi-natural grassland habitat was located at Drigg, W. Cumbria, contaminated primarily by radioactive fallout, from several sources over the past decade. Advantage was made of the deposition of radionuclides from the Chernobyl reactor incident, which occurred during the early stages of the investigation. The study examined the distribution of radiocaesium for the major components of the grassland ecosystem, within the soil-plant-invertebrate-small mammal food chain. Data concerning temporal fluctuation of radionuclide transfer factors between food chain components are presented. The final section examines the spatial distribution of radiocaesium in sediment and the freshwater eel (Anguilla anguilla) in a small stream contaminated by radioactive effluent. The relationship between activity levels in eels and the sediments in which they rest and forage was investigated. Factors influencing uptake of radiocaesium in freshwater fish were also examined. (author)

  16. Assessment of sediment contamination in Casco Bay, Maine, USA

    Energy Technology Data Exchange (ETDEWEB)

    Wade, Terry L. [Geochemical and Environmental Research Group, Texas A and M University, 833 Graham Road, College Station, TX 77845 (United States); Sweet, Stephen T. [Geochemical and Environmental Research Group, Texas A and M University, 833 Graham Road, College Station, TX 77845 (United States)], E-mail: sweet@gerg.tamu.edu; Klein, Andrew G. [Geography Department, Texas A and M University, 814B Eller O and M Building, College Station, TX 77843 (United States)

    2008-04-15

    The current status of contaminant concentrations in Casco Bay, decadal trends of these contaminants and changes in their geographical distribution are assessed using sediment samples collected approximately 10 years apart. In general, regulated contaminants appeared to be decreasing in concentration. Total PAH and dioxins/furans concentrations did not significantly change over this period. Total organochlorine pesticides, 4,4-DDE, 4,4-DDD, total DDT, PCB, tributyltin and total butyltin decreased in concentration. Trace element concentrations in sediments decreased at the majority of the sampling sites for chromium, nickel, and selenium while arsenic, cadmium, copper, lead, mercury, silver, and zinc remained relatively constant. None of the contaminants measured has increased by more than a factor of 2. Selected sites located in the Inner Bay, where concentrations are higher and new inputs were more likely, showed increased concentrations of contaminants. Most contaminants were not found at concentrations expected to adversely affect sediment biota based on ERL/ERM guidelines. - Sediment studies indicate decadal decreases for many chemical contaminants in Casco Bay.

  17. Assessment of sediment contamination in Casco Bay, Maine, USA

    International Nuclear Information System (INIS)

    Wade, Terry L.; Sweet, Stephen T.; Klein, Andrew G.

    2008-01-01

    The current status of contaminant concentrations in Casco Bay, decadal trends of these contaminants and changes in their geographical distribution are assessed using sediment samples collected approximately 10 years apart. In general, regulated contaminants appeared to be decreasing in concentration. Total PAH and dioxins/furans concentrations did not significantly change over this period. Total organochlorine pesticides, 4,4-DDE, 4,4-DDD, total DDT, PCB, tributyltin and total butyltin decreased in concentration. Trace element concentrations in sediments decreased at the majority of the sampling sites for chromium, nickel, and selenium while arsenic, cadmium, copper, lead, mercury, silver, and zinc remained relatively constant. None of the contaminants measured has increased by more than a factor of 2. Selected sites located in the Inner Bay, where concentrations are higher and new inputs were more likely, showed increased concentrations of contaminants. Most contaminants were not found at concentrations expected to adversely affect sediment biota based on ERL/ERM guidelines. - Sediment studies indicate decadal decreases for many chemical contaminants in Casco Bay

  18. Influence of particle sorting in transport of sediment-associated contaminants

    International Nuclear Information System (INIS)

    Lane, L.J.; Hakonson, T.E.

    1982-01-01

    Hydrologic and sediment transport models are developed to route the flow of water and sediment (by particle size classes) in alluvial stream channels. A simplified infiltration model is used to compute runoff from upland areas and flow is routed in ephemeral stream channels to account for infiltration or transmission losses in the channel alluvium. Hydraulic calculations, based on the normal flow assumption and an approximating hydrograph, are used to compute sediment transport by particle size classes. Contaminants associated with sediment particles are routed in the stream channels to predict contaminatant transport by particle size classes. An empirical adjustment factor, the enrichment ratio, is shown to be a function of the particle size distribution of stream bed sediments, contaminant concentrations by particle size, differential sediment transport rates, and the magnitude of the runoff event causing transport of sediment and contaminants. This analysis and an example application in a liquid effluent-receiving area illustrate the significance of particle sorting in transport of sediment associated contaminants

  19. Sediment and contaminant transport in a marine environment

    International Nuclear Information System (INIS)

    Onishi, Y.; Thompson, F.L.

    1986-01-01

    The finite-element model FETRA is an unsteady, verically averaged two-dimensional model to simulate the transport of sediment and contaminants (radionuclides, heavy metals, pesticides, etc.) in coastal and estuarine water. The model, together with the hydrodynamic model CAFE-I, was applied to the Irish Sea to predict the migration and accumulation of sediment (both cohesive and noncohesive) and of a radionuclide (dissolved and sediment-sorbed) in a tide- and wind-driven system. The study demonstrated that FETRA is a useful tool for assessing sediment and toxic contaminant transport in a marine environment

  20. Sediment Capping and Natural Recovery, Contaminant Transport Fundamentals With Applications to Sediment Caps

    National Research Council Canada - National Science Library

    Petrovski, David M; Corcoran, Maureen K; May, James H; Patrick, David M

    2005-01-01

    Engineered sediment caps and natural recovery are in situ remedial alternatives for contaminated sediments, which consist of the artificial or natural placement of a layer of material over a sediment...

  1. Phytoremediation as a management option for contaminated sediments in tidal marshes, flood control areas and dredged sediment landfill sites.

    Science.gov (United States)

    Bert, Valérie; Seuntjens, Piet; Dejonghe, Winnie; Lacherez, Sophie; Thuy, Hoang Thi Thanh; Vandecasteele, Bart

    2009-11-01

    Polluted sediments in rivers may be transported by the river to the sea, spread over river banks and tidal marshes or managed, i.e. actively dredged and disposed of on land. Once sedimented on tidal marshes, alluvial areas or control flood areas, the polluted sediments enter semi-terrestrial ecosystems or agro-ecosystems and may pose a risk. Disposal of polluted dredged sediments on land may also lead to certain risks. Up to a few years ago, contaminated dredged sediments were placed in confined disposal facilities. The European policy encourages sediment valorisation and this will be a technological challenge for the near future. Currently, contaminated dredged sediments are often not valorisable due to their high content of contaminants and their consequent hazardous properties. In addition, it is generally admitted that treatment and re-use of heavily contaminated dredged sediments is not a cost-effective alternative to confined disposal. For contaminated sediments and associated disposal facilities used in the past, a realistic, low cost, safe, ecologically sound and sustainable management option is required. In this context, phytoremediation is proposed in the literature as a management option. The aim of this paper is to review the current knowledge on management, (phyto)remediation and associated risks in the particular case of sediments contaminated with organic and inorganic pollutants. This paper deals with the following features: (1) management and remediation of contaminated sediments and associated risk assessment; (2) management options for ecosystems on polluted sediments, based on phytoremediation of contaminated sediments with focus on phytoextraction, phytostabilisation and phytoremediation of organic pollutants and (3) microbial and mycorrhizal processes occurring in contaminated sediments during phytoremediation. In this review, an overview is given of phytoremediation as a management option for semi-terrestrial and terrestrial ecosystems

  2. A survey of benthic sediment contaminants in reaches of the Columbia River Estuary based on channel sedimentation characteristics.

    Science.gov (United States)

    Counihan, Timothy D; Waite, Ian R; Nilsen, Elena B; Hardiman, Jill M; Elias, Edwin; Gelfenbaum, Guy; Zaugg, Steven D

    2014-06-15

    While previous studies have documented contaminants in fish, sediments, water, and wildlife, few specifics are known about the spatial distribution of contaminants in the Columbia River Estuary (CRE). Our study goal was to characterize sediment contaminant detections and concentrations in reaches of the CRE that were concurrently being sampled to assess contaminants in water, invertebrates, fish, and osprey (Pandion haliaetus) eggs. Our objectives were to develop a survey design based on sedimentation characteristics and then assess whether sediment grain size, total organic carbon (TOC), and contaminant concentrations and detections varied between areas with different sedimentation characteristics. We used a sediment transport model to predict sedimentation characteristics of three 16km river reaches in the CRE. We then compartmentalized the modeled change in bed mass after a two week simulation to define sampling strata with depositional, stable, or erosional conditions. We collected and analyzed bottom sediments to assess whether substrate composition, organic matter composition, and contaminant concentrations and detections varied among strata within and between the reaches. We observed differences in grain size fractions between strata within and between reaches. We found that the fine sediment fraction was positively correlated with TOC. Contaminant concentrations were statistically different between depositional vs. erosional strata for the industrial compounds, personal care products and polycyclic aromatic hydrocarbons class (Indus-PCP-PAH). We also observed significant differences between strata in the number of detections of Indus-PCP-PAH (depositional vs. erosional; stable vs. erosional) and for the flame retardants, polychlorinated biphenyls, and pesticides class (depositional vs. erosional, depositional vs. stable). When we estimated mean contaminant concentrations by reach, we observed higher contaminant concentrations in the furthest downstream

  3. A survey of benthic sediment contaminants in reaches of the Columbia River Estuary based on channel sedimentation characteristics

    Science.gov (United States)

    Counihan, Timothy D.; Waite, Ian R.; Nilsen, Elena B.; Hardiman, Jill M.; Elias, Edwin; Gelfenbaum, Guy; Zaugg, Steven D.

    2014-01-01

    While previous studies have documented contaminants in fish, sediments, water, and wildlife, few specifics are known about the spatial distribution of contaminants in the Columbia River Estuary (CRE). Our study goal was to characterize sediment contaminant detections and concentrations in reaches of the CRE that were concurrently being sampled to assess contaminants in water, invertebrates, fish, and osprey (Pandion haliaetus) eggs. Our objectives were to develop a survey design based on sedimentation characteristics and then assess whether sediment grain size, total organic carbon (TOC), and contaminant concentrations and detections varied between areas with different sedimentation characteristics. We used a sediment transport model to predict sedimentation characteristics of three 16 km river reaches in the CRE. We then compartmentalized the modeled change in bed mass after a two week simulation to define sampling strata with depositional, stable, or erosional conditions. We collected and analyzed bottom sediments to assess whether substrate composition, organic matter composition, and contaminant concentrations and detections varied among strata within and between the reaches. We observed differences in grain size fractions between strata within and between reaches. We found that the fine sediment fraction was positively correlated with TOC. Contaminant concentrations were statistically different between depositional vs. erosional strata for the industrial compounds, personal care products and polycyclic aromatic hydrocarbons class (Indus–PCP–PAH). We also observed significant differences between strata in the number of detections of Indus–PCP–PAH (depositional vs. erosional; stable vs. erosional) and for the flame retardants, polychlorinated biphenyls, and pesticides class (depositional vs. erosional, depositional vs. stable). When we estimated mean contaminant concentrations by reach, we observed higher contaminant concentrations in the furthest

  4. Environmental impact of ongoing sources of metal contamination on remediated sediments

    Energy Technology Data Exchange (ETDEWEB)

    Knox, Anna Sophia, E-mail: anna.knox@srn.doe.gov [Savannah River National Laboratory, Aiken, SC 29808 (United States); Paller, Michael H., E-mail: michael.paller@srnl.doe.gov [Savannah River National Laboratory, Aiken, SC 29808 (United States); Milliken, Charles E., E-mail: charles.milliken@srnl.doe.gov [Savannah River National Laboratory, Aiken, SC 29808 (United States); Redder, Todd M., E-mail: tredder@limno.com [LimnoTech, Ann Arbor, Minnesota 48108 (United States); Wolfe, John R., E-mail: jwolfe@limno.com [LimnoTech, Ann Arbor, Minnesota 48108 (United States); Seaman, John, E-mail: seaman@srel.uga.edu [Savannah River Ecology Laboratory, University of Georgia, Aiken, SC 29802 (United States)

    2016-09-01

    A challenge to all remedial approaches for contaminated sediments is the continued influx of contaminants from uncontrolled sources following remediation. We investigated the effects of ongoing contamination in mesocosms employing sediments remediated by different types of active and passive caps and in-situ treatment. Our hypothesis was that the sequestering agents used in active caps and in situ treatment will bind elements (arsenic, chromium, cadmium, cobalt, copper, nickel, lead, selenium, and zinc) from ongoing sources thereby reducing their bioavailability and protecting underlying remediated sediments from recontamination. Most element concentrations in surface water remained significantly lower in mesocosms with apatite and mixed amendment caps than in mesocosms with passive caps (sand), uncapped sediment, and spike solution throughout the 2520 h experiment. Element concentrations were significantly higher in Lumbriculus variegatus from untreated sediment than in Lumbriculus from most active caps. Pearson correlations between element concentrations in Lumbriculus and metal concentrations in the top 2.5 cm of sediment or cap measured by diffusive gradient in thin films (DGT) sediment probes were generally strong (as high as 0.98) and significant (p < 0.05) for almost all tested elements. Metal concentrations in both Lumbriculus and sediment/cap were lowest in apatite, mixed amendment, and activated carbon treatments. These findings show that some active caps can protect remediated sediments by reducing the bioavailable pool of metals/metalloids in ongoing sources of contamination. - Graphical abstract: Conventional methods of remediating contaminated sediments may be inadequate for the protection of benthic organisms when ongoing sources of contamination are present. However, sediment caps with chemically active sequestering agents have the ability to reduce the bioavailable pool of metals in ongoing sources of contamination (red dots), reduce toxicity to

  5. Environmental impact of ongoing sources of metal contamination on remediated sediments

    International Nuclear Information System (INIS)

    Knox, Anna Sophia; Paller, Michael H.; Milliken, Charles E.; Redder, Todd M.; Wolfe, John R.; Seaman, John

    2016-01-01

    A challenge to all remedial approaches for contaminated sediments is the continued influx of contaminants from uncontrolled sources following remediation. We investigated the effects of ongoing contamination in mesocosms employing sediments remediated by different types of active and passive caps and in-situ treatment. Our hypothesis was that the sequestering agents used in active caps and in situ treatment will bind elements (arsenic, chromium, cadmium, cobalt, copper, nickel, lead, selenium, and zinc) from ongoing sources thereby reducing their bioavailability and protecting underlying remediated sediments from recontamination. Most element concentrations in surface water remained significantly lower in mesocosms with apatite and mixed amendment caps than in mesocosms with passive caps (sand), uncapped sediment, and spike solution throughout the 2520 h experiment. Element concentrations were significantly higher in Lumbriculus variegatus from untreated sediment than in Lumbriculus from most active caps. Pearson correlations between element concentrations in Lumbriculus and metal concentrations in the top 2.5 cm of sediment or cap measured by diffusive gradient in thin films (DGT) sediment probes were generally strong (as high as 0.98) and significant (p < 0.05) for almost all tested elements. Metal concentrations in both Lumbriculus and sediment/cap were lowest in apatite, mixed amendment, and activated carbon treatments. These findings show that some active caps can protect remediated sediments by reducing the bioavailable pool of metals/metalloids in ongoing sources of contamination. - Graphical abstract: Conventional methods of remediating contaminated sediments may be inadequate for the protection of benthic organisms when ongoing sources of contamination are present. However, sediment caps with chemically active sequestering agents have the ability to reduce the bioavailable pool of metals in ongoing sources of contamination (red dots), reduce toxicity to

  6. Sediment and toxic contaminant transport modeling in coastal waters

    International Nuclear Information System (INIS)

    Onishi, Yasuo; Mayer, D.W.; Argo, R.S.

    1982-01-01

    Models are presented to estimate the migration of toxic contaminants in coastal waters. Ocean current is simulated by the vertically-averaged, finite element, two-demensional model known as CAFE-I with the Galerkin weighted residual technique. The refraction of locally generated waves or swells is simulated by the wave refraction model, LO3D. Using computed current, depth, and wave characteristics, the finite element model, FETRA, simulated sediment and contaminant transport in coastal waters, estuaries and rivers. Prior to the application of these models to the Irish Sea and other coastal waters, the finite element model, FETRA, was tested to demonstrate its ability to simulate sediment and contaminant interaction, and the mechanism governing the transport, deposition, and resuspension of contaminated sediment. Several simple equations such as the unsteady, advection-diffusion equation, the equation for noncohesive-sediment load due to wind-induced waves in offshore and surf zones, and the equation for sediment-radionuclide transport simulation were solved during the preliminary testing of the model. (Kato, T.)

  7. The influence of hydrology on lacustrine sediment contaminant records

    Science.gov (United States)

    Rosen, Michael R.

    2015-01-01

    The way water flows to a lake, through streams, as runoff, or as groundwater, can control the distribution and mass of sediment and contaminants deposited. Whether a lake is large or small, deep or shallow, open or closed, the movement of water to a lake and the circulation patterns of water within a lake control how and where sediment and contaminants are deposited. Particle-associated contaminants may stay close to the input source of contamination or be transported by currents to bathymetric lows. A complex morphology of the lake bottom or shoreline can also affect how contaminants will be distributed. Dissolved contaminants may be widely dispersed in smaller lakes, but may be diluted in large lakes away from the source. Although dissolved contaminants may not be deposited in lake sediments, the impact of dissolved contaminants (such as nitrogen) may be reflected by the ecosystem. For instance, increased phosphorus and nitrogen may increase organic content or algal biomass, and contribute to eutrophication of the lake over time. Changes in oxidation-reduction potential at the sediment-water interface may either release some contaminants to the water column or conversely deposit other contaminants to the sediment depending on the compound’s chemical characteristics. Changes in land use generally affect the hydrology of the watershed surrounding a lake, providing more runoff if soil binding vegetation is removed or if more impervious cover (roads and buildings) is increased. Groundwater inputs may change if pumping of the aquifer connected to the lake occurs. Even if groundwater is only a small portion of the volume of water entering a lake, if contaminant concentrations in the aquifer are high compared to surface water inputs, the mass of contaminants from groundwater may be as, or more, important than surface water contributions.

  8. Mercury contaminated sediment sites—An evaluation of remedial options

    Energy Technology Data Exchange (ETDEWEB)

    Randall, Paul M., E-mail: randall.paul@epa.gov [U.S. Environmental Protection Agency, Office of Research and Development, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, OH 45268 (United States); Chattopadhyay, Sandip, E-mail: Sandip.Chattopadhyay@tetratech.com [Tetra Tech, Inc., 250 West Court Street, Suite 200W, Cincinnati, OH 45202 (United States)

    2013-08-15

    Mercury (Hg) is a naturally-occurring element that is ubiquitous in the aquatic environment. Though efforts have been made in recent years to decrease Hg emissions, historically-emitted Hg can be retained in the sediments of aquatic bodies where they may be slowly converted to methylmercury (MeHg). Consequently, Hg in historically-contaminated sediments can result in high levels of significant exposure for aquatic species, wildlife and human populations consuming fish. Even if source control of contaminated wastewater is achievable, it may take a very long time, perhaps decades, for Hg-contaminated aquatic systems to reach relatively safe Hg levels in both water and surface sediment naturally. It may take even longer if Hg is present at higher concentration levels in deep sediment. Hg contaminated sediment results from previous releases or ongoing contributions from sources that are difficult to identify. Due to human activities or physical, chemical, or biological processes (e.g. hydrodynamic flows, bioturbation, molecular diffusion, and chemical transformation), the buried Hg can be remobilized into the overlying water. Hg speciation in the water column and sediments critically affect the reactivity (i.e. conversion of inorganic Hg(II) to MeHg), transport, and its exposure to living organisms. Also, geochemical conditions affect the activity of methylating bacteria and its availability for methylation. This review paper discusses remedial considerations (e.g. key chemical factors in fate and transport of Hg, source characterization and control, environmental management procedures, remediation options, modeling tools) and includes practical case studies for cleaning up Hg-contaminated sediment sites. -- Highlights: ► Managing mercury-contaminated sediment sites are challenging to remediate. ► Remediation technologies are making a difference in managing these sites. ► Partitioning plays a dominant role in the distribution of mercury species. ► Mathematical

  9. Sediment and toxic contaminant transport modeling in coastal waters

    International Nuclear Information System (INIS)

    Onishi, Y.; Mayer, D.W.; Argo, R.S.

    1982-02-01

    A hydrodynamic model, CAFE-I, a wave refraction model, LO3D, and a sediment and contaminant transport model, FETRA, were selected as tools for evaluating exposure levels of radionuclides, heavy metals, and other toxic chemicals in coastal waters. Prior to the application of these models to the Irish Sea and other coastal waters, the finite element model, FETRA, was tested to demonstrate its ability to simulate sediment and contaminant interactions (e.g., adsorption and desorption), and the mechanisms governing the transport, deposition, and resuspension of contaminated sediments

  10. Estimating release of polycyclic aromatic hydrocarbons from coal-tar contaminated soil at manufactured gas plant sites. Final report

    International Nuclear Information System (INIS)

    Lee, L.S.

    1998-04-01

    One of EPRI's goals regarding the environmental behavior of organic substances consists of developing information and predictive tools to estimate the release potential of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils at manufactured gas (MGP) plant sites. A proper assessment of the distribution of contaminants under equilibrium conditions and the potential for mass-transfer constraints is essential in evaluating the environmental risks of contaminants in the subsurface at MGP sites and for selecting remediation options. The results of this research provide insights into estimating maximum release concentrations of PAHs from MGP soils that have been contaminated by direct contact with the tar or through years of contact with contaminated groundwater. Attention is also given to evaluating the use of water-miscible cosolvents for estimating aqueous phase concentrations, and assessing the role of mass-transfer constraints in the release of PAHs from MGP site soils

  11. Resuspended contaminated sediments cause sublethal stress to oysters: A biomarker differentiates total suspended solids and contaminant effects.

    Science.gov (United States)

    Edge, Katelyn J; Dafforn, Katherine A; Simpson, Stuart L; Ringwood, Amy H; Johnston, Emma L

    2015-06-01

    Resuspended contaminated sediments represent an important route of contaminant exposure for aquatic organisms. During resuspension events, filter-feeding organisms are exposed to contaminants, in both the dissolved form (at the gills) and the particulate form (in the digestive system). In addition, these organisms must manage the physical stress associated with an increase in total suspended solids (TSS). To date, few studies have experimentally compared the contributions to biological stress of contaminated and clean suspended solids. The authors mixed field-collected sediments (cellular biomarkers (lysosomal membrane stability, lipid peroxidation, and glutathione) were measured to evaluate sublethal toxicity. Lysosomal membrane stability was the most sensitive biomarker for distinguishing effects from resuspended contaminated sediments, as increasing amounts of contaminated TSS increased lysosomal membrane destabilization. The authors' results illustrate the importance of considering contaminant exposures from resuspended sediments when assessing the toxicity of contaminants to aquatic organisms. © 2015 SETAC.

  12. Tracking riverborne sediment and contaminants in Commencement Bay, Washington, using geochemical signatures

    Science.gov (United States)

    Takesue, Renee K.; Conn, Kathleen E.; Dinicola, Richard S.

    2017-09-29

    Large rivers carry terrestrial sediment, contaminants, and other materials to the coastal zone where they can affect marine biogeochemical cycles and ecosystems. This U.S. Geological Survey study combined river and marine sediment geochemistry and organic contaminant analyses to identify riverborne sediment and associated contaminants at shoreline sites in Commencement Bay, Puget Sound, Washington, that could be used by adult forage fish and other marine organisms. Geochemical signatures distinguished the fine fraction (contaminants were measured in surface sediment did not have measurable 7Be activities in that layer, so their contaminant assemblages were attributed to sources from previous years. Concentrations of organic contaminants (the most common of which were polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and fecal sterols) were higher in the contaminants in marine rather than river sediment, indicates that riverborne sediment-bound contaminants are retained in shallow marine habitats of Commencement Bay. The retention of earlier inputs complicates efforts to identify recent inputs and sources. Understanding modern sources and fates of riverborne sediment and contaminants and their potential ecological impacts will therefore require a suite of targeted geochemical studies in such marine depositional environments.

  13. Recolonization and succession of subtidal macrobenthic infauna in sediments contaminated with cadmium

    International Nuclear Information System (INIS)

    Lu, L.; Wu, R.S.S.

    2003-01-01

    No significant differences in abundance, species number, diversity and species composition were found between cadmium-contaminated and control sediments after 14 months. - Recolonization and succession of macrobenthic infauna in defaunated sediment contaminated with Cd were studied over a period of 14 months. Trays with defaunated sediment contaminated with cadmium, and trays with defaunated (control) sediment, were exposed at the subtidal in a subtropical environment. Macrobenthic succession exhibited different patterns in Cd-contaminated and control sediments. Abundance and species number were significantly higher in Cd-contaminated sediment during early succession, suggesting that cadmium may facilitate recolonization of certain species of macrobenthos. Cadmium also led to a significant change in species composition in initial colonization and subsequent succession. No significant difference in abundance, species number, diversity and species composition was found between Cd-contaminated and control sediments at the end of experiment, suggesting a stable benthic community was arrived within 14 months

  14. Recolonization and succession of subtidal macrobenthic infauna in sediments contaminated with cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Lu, L.; Wu, R.S.S

    2003-01-01

    No significant differences in abundance, species number, diversity and species composition were found between cadmium-contaminated and control sediments after 14 months. - Recolonization and succession of macrobenthic infauna in defaunated sediment contaminated with Cd were studied over a period of 14 months. Trays with defaunated sediment contaminated with cadmium, and trays with defaunated (control) sediment, were exposed at the subtidal in a subtropical environment. Macrobenthic succession exhibited different patterns in Cd-contaminated and control sediments. Abundance and species number were significantly higher in Cd-contaminated sediment during early succession, suggesting that cadmium may facilitate recolonization of certain species of macrobenthos. Cadmium also led to a significant change in species composition in initial colonization and subsequent succession. No significant difference in abundance, species number, diversity and species composition was found between Cd-contaminated and control sediments at the end of experiment, suggesting a stable benthic community was arrived within 14 months.

  15. Some properties of suspended sediment absorbed cations in turbid freshwaters of South Africa

    International Nuclear Information System (INIS)

    Grobbelaar, J.U.; Stegmann, P.; Keulder, P.C.

    1980-01-01

    Large quantities of suspended sediments are common in many of South Africa's freshwaters. Temporal and spatial variations in the amounts of cations adsorbed were recorded. The adsorption appears to be dependent on valency, because greater quantities of the higher valencies are adsorbed. Ca++ dominated the adsorbed cations and Mg++ the dissolved fraction. Water originating from the Beaufort Series contained high sodium concentrations. Fe++ dominated the adsorbed minor cations. Large quantities of sediments transported by rivers enter impoundments. The adsorbed ions transported in this way are influenced by the type of suspended sediment and form a significant part of the total input of ions

  16. Occurrence of triclosan, triclocarban, and its lesser chlorinated congeners in Minnesota freshwater sediments collected near wastewater treatment plants

    Science.gov (United States)

    Venkatesan, Arjun K.; Pycke, Benny F.G.; Barber, Larry B.; Lee, Kathy E.; Halden, Rolf U.

    2012-01-01

    The antimicrobial agents triclosan (TCS), triclocarban (TCC) and their associated transformation products are of increasing concern as environmental pollutants due to their potential adverse effects on humans and wildlife, including bioaccumulation and endocrine-disrupting activity. Analysis by tandem mass spectrometry of 24 paired freshwater bed sediment samples (top 10 cm) collected by the U.S. Geological Survey near 12 wastewater treatment plants (WWTPs) in Minnesota revealed TCS and TCC concentrations of up to 85 and 822 ng/g dry weight (dw), respectively. Concentrations of TCS and TCC in bed sediments collected downstream of WWTPs were significantly greater than upstream concentrations in 58% and 42% of the sites, respectively. Dichloro- and non-chlorinated carbanilides (DCC and NCC) were detected in sediments collected at all sites at concentrations of up to 160 and 1.1 ng/g dw, respectively. Overall, antimicrobial concentrations were significantly higher in lakes than in rivers and creeks, with relative abundances decreasing from TCC > TCS > DCC > NCC. This is the first statewide report on the occurrence of TCS, TCC and TCC transformation products in freshwater sediments. Moreover, the results suggest biological or chemical TCC dechlorination products to be ubiquitous in freshwater environments of Minnesota, but whether this transformation occurs in the WWTP or bed sediment remains to be determined.

  17. Coal Tar and Coal-Tar Pitch

    Science.gov (United States)

    Learn about coal-tar products, which can raise your risk of skin cancer, lung cancer, and other types of cancer. Examples of coal-tar products include creosote, coal-tar pitch, and certain preparations used to treat skin conditions such as eczema, psoriasis, and dandruff.

  18. Antimony and arsenic exhibit contrasting spatial distributions in the sediment and vegetation of a contaminated wetland.

    Science.gov (United States)

    Warnken, Jan; Ohlsson, Rohana; Welsh, David T; Teasdale, Peter R; Chelsky, Ariella; Bennett, William W

    2017-08-01

    Antimony is a priority environmental contaminant that is relatively poorly studied compared to other trace metal(loid)s. In particular, the behaviour of antimony in wetland sediments, where anaerobic conditions often dominate, has received considerably less attention compared to well-drained terrestrial soil environments. Here we report the results of a spatial assessment of antimony in the sediments and vegetation of a freshwater wetland exposed to stibnite tailings for the past forty years. The concentration of antimony in the sediment decreased rapidly with distance from the tailings deposit, from a maximum of ∼22,000 mg kg -1 to ∼1000 mg kg -1 at a distance of ∼150 m. In contrast, arsenic was distributed more evenly across the wetland, indicating that it was more mobile under the prevailing hypoxic/anoxic conditions. Less clear trends were observed in the tissues of wetland plants, with the concentrations of antimony in waterlilies (2.5-195 mg kg -1 ) showing no clear trends with distance from the tailings deposit, and no correlation with sediment concentrations. Sedges and Melaleuca sp. trees had lower antimony concentrations (<25 mg kg -1 and 5 mg kg -1 , respectively) compared to waterlilies, but showed a non-significant trend of higher concentrations closer to the tailings. For all vegetation types sampled, antimony concentrations were consistently lower than arsenic concentrations (Sb:As = 0.27-0.31), despite higher concentrations of antimony in the sediment. Overall, the results of this study highlight clear differences in the behaviour of antimony and arsenic in freshwater wetlands, which should be considered during the management and remediation of such sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Sensitivity ranking for freshwater invertebrates towards hydrocarbon contaminants.

    Science.gov (United States)

    Gerner, Nadine V; Cailleaud, Kevin; Bassères, Anne; Liess, Matthias; Beketov, Mikhail A

    2017-11-01

    Hydrocarbons have an utmost economical importance but may also cause substantial ecological impacts due to accidents or inadequate transportation and use. Currently, freshwater biomonitoring methods lack an indicator that can unequivocally reflect the impacts caused by hydrocarbons while being independent from effects of other stressors. The aim of the present study was to develop a sensitivity ranking for freshwater invertebrates towards hydrocarbon contaminants, which can be used in hydrocarbon-specific bioindicators. We employed the Relative Sensitivity method and developed the sensitivity ranking S hydrocarbons based on literature ecotoxicological data supplemented with rapid and mesocosm test results. A first validation of the sensitivity ranking based on an earlier field study has been conducted and revealed the S hydrocarbons ranking to be promising for application in sensitivity based indicators. Thus, the first results indicate that the ranking can serve as the core component of future hydrocarbon-specific and sensitivity trait based bioindicators.

  20. The distribution of radionuclides between the dissolved and particulate phases of a contaminated freshwater stream

    International Nuclear Information System (INIS)

    Murdock, R.N.; Johnson, M.S.; Hemingway, J.D.

    1995-01-01

    Streamwater concentrations of the radionuclides 137 Cs, 241 Am and 239,240 Pu from a contaminated freshwater stream showed significant relationships between total concentration and flow rate. When total concentrations were divided into their dissolved and particulate components 239,240 Pu was shown to exist mainly (>80%) in the solute phase ( 137 Cs and 241 Am were distributed equally between the two phases. 137 Cs was most likely present either as the dissolved ion or as the specifically adsorbed ion on particulate sediments. Particle-associated 241 Am and the small particulate component of 239,240 Pu, were believed to be bound to sediment surface coatings, such as organic or oxide/hydroxides, rather than the truly adsorbed ion. Solute phase 239,240 Pu was most likely associated with colloidal organic carbon species (such as humic or fulvic acids). This was also apparent, but to a lesser extent, for 241 Am. Distribution coefficients were determined for a number of discrete sites and environmental conditions. The response of the stream to removal of its source of radioactivity (via a re-routing scheme) was both significant and rapid. (author)

  1. Beyond the bed: Effects of metal contamination on recruitment to bedded sediments and overlying substrata

    International Nuclear Information System (INIS)

    Hill, Nicole A.; Simpson, Stuart L.; Johnston, Emma L.

    2013-01-01

    Metal-contaminated sediments pose a recognised threat to sediment-dwelling fauna. Re-mobilisation of contaminated sediments however, may impact more broadly on benthic ecosystems, including on diverse assemblages living on hard substrata patches immediately above sediments. We used manipulative field experiments to simultaneously test for the effects of metal contamination on recruitment to marine sediments and overlying hard substrata. Recruitment to sediments was strongly and negatively affected by metal contamination. However, while assemblage-level effects on hard-substratum fauna and flora were observed, most functional groups were unaffected or slightly enhanced by exposure to contaminated sediments. Diversity of hard-substratum fauna was also enhanced by metal contamination at one site. Metal-contaminated sediments appear to pose less of a hazard to hard-substratum than sediment-dwelling assemblages, perhaps due to a lower direct contaminant exposure or to indirect effects mediated by contaminant impacts on sediment fauna. Our results indicate that current sediment quality guidelines are protective of hard-substrata organisms. - Highlights: ► Potential for contaminated sediments to exert impacts beyond the sediment communities. ► We examine effects on recruitment to sediments and overlying hard substrata simultaneously. ► Metal-contaminated sediments had a strong negative impact on sediment fauna. ► Metal-contaminated sediments pose less of a hazard to hard-substratum fauna. ► Sediment quality guidelines are likely protective of hard-substrata organisms. - Under natural disturbance regimes, metal-contaminated sediments pose less of a direct risk to hard-substratum fauna than to sediment-dwelling fauna and SQG appear appropriate.

  2. Incorporating Contaminant Bioavailability into Sediment Quality Assessment Frameworks

    Science.gov (United States)

    The recently adopted sediment quality assessment framework for evaluating bay and estuarine sediments in the State of California incorporates bulk sediment chemistry as a key line of evidence(LOE) but does not address the bioavailability of measured contaminants. Thus, the chemis...

  3. MOIRA: a computerised decision support system for the management of radionuclide contaminated freshwater ecosystems

    International Nuclear Information System (INIS)

    Gallego, Eduardo; Brittain, John E.; Hakanson, Lars; Heling, Rudie; Hofman, Dmitry; Monte, Luigi

    2004-01-01

    The radiation dose resulting from contamination of freshwater ecosystems due to the release of radioactive substances into the environment may be reduced by applying suitable countermeasures. Despite their benefits, intervention strategies may have detrimental effects of economic, ecological and social nature. Thus, it is of paramount importance to assess, by objective criteria, the global cost-benefit balance of different options. The MOIRA project (A MOdel based computerised system for management support to Identify optimal remedial strategies for Restoring radionuclide contaminated Aquatic ecosystems) has developed a user-friendly, computerised tool that will allow decision makers to choose optimal intervention strategies for freshwater ecosystems with different contamination scenarios. The aim of the paper is to briefly describe the main components of the MOIRA system and to demonstrate its application using real case based scenarios. (author)

  4. Changes of freshwater-lens thickness in basaltic island aquifers overlain by thick coastal sediments

    Science.gov (United States)

    Rotzoll, Kolja; Oki, Delwyn S.; El-Kadi, Aly I.

    2010-01-01

    Freshwater-lens thickness and long-term changes in freshwater volume in coastal aquifers are commonly assessed through repeated measurement of salinity profiles from monitor wells that penetrate into underlying salt water. In Hawaii, the thickest measured freshwater lens is currently 262 m in dike-free, volcanic-rock aquifers that are overlain by thick coastal sediments. The midpoint depth (depth where salinity is 50% salt water) between freshwater and salt water can serve as an indicator for freshwater thickness. Most measured midpoints have risen over the past 40 years, indicating a shrinking lens. The mean rate of rise of the midpoint from 1999–2009 varied locally, with faster rates in highly developed areas (1.0 m/year) and slower rates in less developed areas (0.5 m/year). The thinning of the freshwater lenses is the result of long-term groundwater withdrawal and reduced recharge. Freshwater/salt-water interface locations predicted from measured water levels and the Ghyben-Herzberg principle may be deeper than measured midpoints during some periods and shallower during other periods, although depths may differ up to 100 m in some cases. Moreover, changes in the midpoint are slower than changes in water level. Thus, water levels may not be a reliable indicator of the amount of freshwater in a coastal aquifer.

  5. Metal concentrations in stream biofilm and sediments and their potential to explain biofilm microbial community structure

    International Nuclear Information System (INIS)

    Ancion, Pierre-Yves; Lear, Gavin; Dopheide, Andrew; Lewis, Gillian D.

    2013-01-01

    Concentrations of metals associated with sediments have traditionally been analysed to assess the extent of heavy metal contamination in freshwater environments. Stream biofilms present an alternative medium for this assessment which may be more relevant to the risk incurred by stream ecosystems as they are intensively grazed by aquatic organisms at a higher trophic level. Therefore, we investigated zinc, copper and lead concentrations in biofilms and sediments of 23 stream sites variously impacted by urbanisation. Simultaneously, biofilm bacterial and ciliate protozoan community structure was analysed by Automated Ribosomal Intergenic Spacer Analysis and Terminal Restriction Fragment Length Polymorphism, respectively. Statistical analysis revealed that biofilm associated metals explained a greater proportion of the variations observed in bacterial and ciliate communities than did sediment associated-metals. This study suggests that the analysis of metal concentrations in biofilms provide a good assessment of detrimental effects of metal contaminants on aquatic biota. - Highlights: ► Zn, Cu and Pb concentrations in biofilm and sediments from 23 streams were assessed. ► Bacteria and ciliate protozoa were simultaneously used as biological indicators. ► Zn and Cu were generally enriched in biofilm compared to sediments. ► Metals in biofilm provide a useful assessment of freshwater ecosystem contamination. ► Results highlight the likely ecological importance of biofilm associated metals. - Metal concentrations in stream biofilms provide a good assessment of the effects of trace metal contaminants on freshwater ecosystems.

  6. Evolution of bacterial community during bioremediation of PAHs in a coal tar contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Lors, C.; Ryngaert, A.; Perie, F.; Diels, L.; Damidot, D. [University of Lille, Lille (France)

    2010-11-15

    The monitoring of a windrow treatment applied to soil contaminated by mostly 2, 3- and 4-ring PAHs produced by coal tar distillation was performed by following the evolution of both PAH concentration and the bacterial community. Total and PAH-degrading bacterial community structures were followed by 165 rRNA PCR-DGGE in parallel with quantification by bacterial counts and 16 PAH measurements. Six months of biological treatment led to a strong decrease in 2-, 3- and 4-ring PAH concentrations (98, 97 and 82%, respectively). This result was associated with the activity of bacterial PAH-degraders belonging mainly to the Gamma proteobacteria, in particular the Enterobacteria and Pseudomonas genera which were detected over the course of the treatment. This group was considered to be a good bioindicator to determine the potential PAH biodegradation of contaminated soil. Conversely other species like the Beta proteobacteria were detected after 3 months when 2-, 3- and 4-ring PAHs were almost completely degraded. Thus presence of the Beta proteobacteria group could be considered a good candidate indicator to estimate the endpoint of biotreatment of this type of PAH contaminated soil.

  7. Environmental magnetic methods for detecting and mapping contaminated sediments in lakes

    Science.gov (United States)

    Boyce, J. I.

    2009-05-01

    The remediation of contaminated sediments is an urgent environmental priority in the Great Lakes and requires detailed mapping of impacted sediment layer thickness, areal distribution and pollutant levels. Magnetic property measurements of sediment cores from two heavily polluted basins in Lake Ontario (Hamilton Harbour, Frenchman's Bay) show that concentrations of hydrocarbons (PAH) and a number of heavy metals (Pb, As, Ni, Cu, Cr, Zn, Cd, Fe) are strongly correlated with magnetic susceptibility. The magnetic susceptibility contrast between the contaminated sediment and underlying 'pre-colonial' sediments is sufficient to generate a total field anomaly (ca. 2-20 nT) that can be measured with a magnetometer towed above the lake bed. Systematic magnetic surveying (550 line km) of Hamilton Harbour using a towed marine magnetometer clearly identifies a number of well-defined magnetic anomalies that coincide with known accumulations of contaminated lake sediment. When calibrated against in-situ magnetic property measurements, the modeled apparent susceptibility from magnetic survey results can be used to classify the relative contaminant impact levels. The results demonstrate the potential of magnetic property measurements for rapid reconnaissance mapping of large areas of bottom contamination prior to detailed coring and sediment remediation.

  8. Atrazine Contamination and Potential Health Effects on Freshwater Mussel Uniandra contradens Living in Agricultural Catchment at Nan Province, Thailand

    Directory of Open Access Journals (Sweden)

    Tongchai Thitiphuree

    2013-01-01

    Full Text Available Seasonal cultivation in northern part of Thailand leads to widely uses of agrochemicals especially atrazine herbicide. To examine whether an intensive use of atrazine could lead to contamination in aquatic environment, sediment and water were collected from an agricultural catchment in Nan Province during 2010-2011 and subjected to analysis for atrazine by GC-MS. The results showed that detectable levels of atrazine were found in water (0.16 µg/ml and sediment (0.23 µg/g of the catchment. To monitor potential effects of atrazine on aquatic animals, a freshwater mussel Uniandra contradens was used as a sentinel species for bioaccumulation and potential health effects. Mussels collected from the catchment during 2010-2011 were subjected to analysis for atrazine residue in tissue and condition factor based on body weight and shell length. The results showed that detectable levels of atrazine were found in mussel tissue with the highest level (8.40  2.06 ng/g in late wet season when runoff from heavy rain was evidenced. Condition factor, an indicative of overall health, showed a significant negative correlation with atrazine residue in the tissue. This information could be used as part of the monitoring program for herbicide contamination and potential health effects in agricultural environment.

  9. Surface sediment quality relative to port activities: A contaminant-spectrum assessment.

    Science.gov (United States)

    Yu, Shen; Hong, Bing; Ma, Jun; Chen, Yongshan; Xi, Xiuping; Gao, Jingbo; Hu, Xiuqin; Xu, Xiangrong; Sun, Yuxin

    2017-10-15

    Ports are facing increasing environmental concerns with their importance to the global economy. Numerous studies indicated sediment quality deterioration in ports; however, the deterioration is not discriminated for each port activity. This study investigated a spectrum of contaminants (metals and organic pollutants) in surface sediments at 20 sampling points in Port Ningbo, China, one of the top five world ports by volume. The spectrum of contaminants (metals and organic pollutants) was quantified following marine sediment quality guidelines of China and USA and surface sediment quality was assessed according to thresholds of the two guidelines. Coupling a categorical matrix of port activities with the matrix of sedimentary contaminants revealed that contaminants were highly associated with the port operations. Ship repair posed a severe chemical risk to sediment. Operations of crude oil and coal loadings were two top activities related to organic pollutants in sediments while port operations of ore and container loadings discharged metals. Among the 20 sampling points, Cu, Zn, Pb, and DDT and its metabolites were the priority contaminants influencing sediment quality. Overall, surface sediments in Port Ningbo had relatively low environmental risks but ship repair is an environmental concern that must be addressed. This study provides a practical approach for port activity-related quality assessment of surface sediments in ports that could be applicable in many world sites. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. UTILIZATION OF AQUEOUS-TAR CONDENSATES FORMED DURING GASIFICATION

    Directory of Open Access Journals (Sweden)

    Anna Kwiecińska

    2016-11-01

    Full Text Available Gasification of solid fuels is an alternative process for energy production using conventional and renewable fuels. Apart from desired compounds, i.e. carbon oxide, hydrogen and methane, the produced gas contains complex organic (tars and inorganic (carbonizate, ammonia contaminants. Those substances, together with water vapor, condensate during cooling of the process gas, what results in the formation of aqueous-tar condensate, which requires proper methods of utilization. The management of this stream is crucial for commercialization and application of the gasification technology. In the paper the treatment of aqueous-tar condensates formed during biomass gasification process is discussed. The removal of tars from the stream was based on their spontaneous separation. The aqueous stream was subjected to ultrafiltration operated at different pressures. Such a treatment configuration enabled to obtain highly concentrated retentate, which could be recycled to the gasifier, and filtrate, which could be subjected to further treatment.

  11. Development, evaluation, and application of sediment quality targets for assessing and managing contaminated sediments in Tampa Bay, Florida

    Science.gov (United States)

    MacDonald, D.D.; Carr, R.S.; Eckenrod, D.; Greening, H.; Grabe, S.; Ingersoll, C.G.; Janicki, S.; Janicki, T.; Lindskoog, R.A.; Long, E.R.; Pribble, R.; Sloane, G.; Smorong, D.E.

    2004-01-01

    Tampa Bay is a large, urban estuary that is located in west central Florida. Although water quality conditions represent an important concern in this estuary, information from numerous sources indicates that sediment contamination also has the potential to adversely affect aquatic organisms, aquatic-dependent wildlife, and human health. As such, protecting relatively uncontaminated areas of the bay from contamination and reducing the amount of toxic chemicals in contaminated sediments have been identified as high-priority sediment management objectives for Tampa Bay. To address concerns related to sediment contamination in the bay, an ecosystem-based framework for assessing and managing sediment quality conditions was developed that included identification of sediment quality issues and concerns, development of ecosystem goals and objectives, selection of ecosystem health indicators, establishment of metrics and targets for key indicators, and incorporation of key indicators, metrics, and targets into watershed management plans and decision-making processes. This paper describes the process that was used to select and evaluate numerical sediment quality targets (SQTs) for assessing and managing contaminated sediments. These SQTs included measures of sediment chemistry, whole-sediment and pore-water toxicity, and benthic invertebrate community structure. In addition, the paper describes how the SQTs were used to develop site-specific concentration-response models that describe how the frequency of adverse biological effects changes with increasing concentrations of chemicals of potential concern. Finally, a key application of the SQTs for defining sediment management areas is discussed.

  12. Interactions between eutrophication and contaminants - partitioning, bioaccumulation and effects on sediment-dwelling organisms

    Energy Technology Data Exchange (ETDEWEB)

    Hylland, Ketil; Schaanning, Morten; Skei, Jens; Berge, John Arthur; Eriksen, Dag Oe.; Skoeld, Mattias; Gunnarsson, Jonas

    1997-12-31

    This report describes an experiment on the interactions between eutrophication and contaminants in marine sediments. The experiment was performed in 24 continuously flushed glass aquaria within which three sediment-dwelling species were kept in a marine sediment. A filter-feeder, blue mussel, was kept in downstream aquaria. The experiment combined three environmental factors: oxygen availability, the presence or absence of contaminants, the addition of organic matter. The objectives were: (1) to quantify differences in the partitioning of contaminants between sediment, pore water and biota as a result of the treatment, (2) to quantify effects of treatments and interactions between treatments on sediment-dwelling organisms, (3) to identify differences, if any, in the release of contaminants from the sediment as the result of treatments. All three contaminants bio accumulated to higher levels in sediments with increased levels of organic material. Feeding directly or indirectly appeared to be the major route for bioaccumulation of benzo(a)pyrene and mercury. Cadmium was also controlled by the concentration in pore water. Sediment in enriched aquaria released more contaminants than sediment with low organic content. Organic enrichment strongly affected growth in the three sediment-dwelling organisms. Growth was less affected by decreased oxygen availability. The presence of contaminants had little effect on the three sediment-dwelling species at the concentrations used in the experiment. 103 refs., 14 figs., 12 tabs.

  13. Evaluating the provenance of fine sediment in degraded Freshwater Pearl Mussel habitats.

    Science.gov (United States)

    Blake, Will; Haley, Steve; Goddard, Rupert; Stone, Peter; Broadhead, Kat

    2015-04-01

    Freshwater Pearl Mussels (FWPM), Margaritifera margaritifera, are among the most critically threatened freshwater bivalves worldwide. In addition to their important roles in particle processing, nutrient release, and sediment mixing, they also serve as an ideal target species for evaluation of aquatic ecosystem functioning especially in the context of their symbiotic relationship with Atlantic salmon Salmo salar and brown or sea trout Salmo trutta. Poor water quality, particularly eutrophication, and siltation are considered major contributory factors in the decline of the species hence management of diffuse water pollution from agriculture (DWPA) is a key priority in catchments that host FWPM habitats. Against this background, this study adopted a combined monitoring, surveying and sediment fingerprinting approach to determine the principal sources of fine sediment impacting FWPM habitats in the River Clun, a Special area of Conservation (SAC) for FWPMs in central western UK. Potential sediment production hotspot areas in the ca 200 km2 catchment area upstream of FWPM habitats were initially evaluated using the SCIMAP risk mapping tool. Suspended sediment monitoring was undertaken on the main stem channel where FWPM habitats are located and wet weather catchment walkover surveys undertaken along the upstream river and stream network. Within this monitoring framework, sediment fingerprinting was undertaken at two levels. The first level aimed to link primary catchment sources (cultivated and uncultivated soil, channel bank erosion, and material transported via roads and tracks) to suspended sediment output from each main tributary upstream of the FWPM beds. The second level linked silt in the FWMP beds to the main tributaries, as integrated source end-members, with the inclusion of main channel bank erosion, a notable feature of walkover surveys as an additional source. Geochemical fingerprints, determined by XRF spectroscopy, were dominated by conservative mineral

  14. Contaminated sediment removal from a spent fuel storage canal

    International Nuclear Information System (INIS)

    Geber, K.R.

    1993-01-01

    A leaking underground spent fuel transfer canal between a decommissioned reactor and a radiochemical separations building at the Oak Ridge National Laboratory (ORNL) was found to contain RCRA-hazardous and radioactive sediment. Closure of the Part B RCRA permitted facility required the use of an underwater robotic vacuum and a filtration-containment system to separate and stabilize the contaminated sediment. This paper discusses the radiological controls established to maintain contamination and exposures As Low As Reasonably Achievable (ALARA) during the sediment removal

  15. Technical guidelines for environmental dredging of contaminated sediments

    Science.gov (United States)

    2008-09-01

    This report provides technical guidelines for evaluating : environmental dredging as a sediment remedy component. This document : supports the Contaminated Sediment Remediation Guidance for : Hazardous Waste Sites, released by the U.S. Environmental ...

  16. Toxicological effects of polychlorinated biphenyls (PCBs) on freshwater turtles in the United States.

    Science.gov (United States)

    Ming-Ch'eng Adams, Clare Isabel; Baker, Joel E; Kjellerup, Birthe V

    2016-07-01

    Prediction of vertebrate health effects originating from persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) has remained a challenge for decades thus making the identification of bioindicators difficult. POPs are predominantly present in soil and sediment, where they adhere to particles due to their hydrophobic characteristics. Animals inhabiting soil and sediment can be exposed to PCBs via dermal exposure while others may obtain PCBs through contaminated trophic interaction. Freshwater turtles can serve as bioindicators due to their strong site fidelity, longevity and varied diet. Previous research observed the health effects of PCBs on turtles such as decreased bone mass, changed sexual development and decreased immune responses through studying both contaminated sites along with laboratory experimentation. Higher deformity rates in juveniles, increased mortality and slower growth have also been observed. Toxicological effects of PCBs vary between species of freshwater turtles and depend on the concertation and configuration of PCB congeners. Evaluation of ecotoxicological effects of PCBs in non-endangered turtles could provide important knowledge about the health effects of endangered turtle species thus inform the design of remediation strategies. In this review, the PCB presence in freshwater turtle habitats and the ecotoxicological effects were investigated with the aim of utilizing the health status to identify areas of focus for freshwater turtle conservation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Freshwater and fish

    International Nuclear Information System (INIS)

    Saxen, R.

    1997-01-01

    Severe radioactive contamination of the freshwater environment could have serious consequences for both drinking water and fish. Most of the Nordic countries have an abundance of freshwater lakes and rivers. Finland alone has about 56,000 lakes, each with a surface area of 1 hectare or more. Nearly 10% of Finland's surface is covered with lakes and rivers. In Sweden, about 9% of the surface area is freshwater, in Norway about 5%, and in Denmark only about 2%. Freshwater plays a minor role in Iceland, but even there numerous rivers discharge from the volcanic soils to the Ocean. Cs-137 and 90 Sr are likely to be the most important radionuclides with respect to long term radioactive contamination of freshwater. If radioactive deposition occurs in the absence of snow and ice radionuclides will contaminate the surface water directly and may rapidly enter the aquatic food chain. Fish which eat contaminated plankton become contaminated almost immediately. Deposition during summer increases the transfer for radionuclides to fish since fish metabolism is faster during the warm season. During the cold period, fish metabolism is slow and thus uptake and excretion of radiocaesium are also slow. (EG)

  18. Stabilization and in situ management of radioactive contaminated sediments of Port Hope harbor

    International Nuclear Information System (INIS)

    Dolinar, G.M.; Killey, R.W.D.; Philipase, K.E.

    1991-01-01

    This paper presents the findings of laboratory and field studies undertaken to assess the feasibility of in situ management of contaminated sediments in Port Hope harbor. The contaminated sediments stem from historic releases from an adjacent radium and uranium refinery, and uranium, arsenic, and radium are the most abundant contaminants. With improved emission controls, currently accumulating sediments have much lower levels of contamination, and the harbor waters currently meet water quality limits for the contaminants of concern. Within a few years, however, the continuing sedimentation will render the harbor unusable. Field tests have confirmed the dredging will result in incomplete removal of the contaminated sediments and that sediment suspension and the release of pores waters during dredging will produce harbor water contaminant concentrations that would require the treatment of large volumes of water. In addition, no remedial work can start until a site for the dredged material can be found. The local community inquired whether in situ burial of the sediments and abandonment of the harbor would provide safe disposal

  19. Tracing salmon-derived nutrients and contaminants in freshwater food webs across a pronounced spawner density gradient.

    Science.gov (United States)

    Gregory-Eaves, Irene; Demers, J Marc J; Kimpe, Lynda; Krümmel, Eva M; Macdonald, Robie W; Finney, Bruce P; Blais, Jules M

    2007-06-01

    Many have demonstrated that anadromous Pacific salmon are significant vectors of nutrients from the ocean to freshwaters. Recently. however, it has been recognized that salmon spawners also input significant quantities of contaminants. The objectives of this paper are to delineate the extent to which salmon-derived nutrients are integrated into the freshwater food web using delta(15)N and delta(13)C and to assess the influence of the salmon pathway in the accumulation of contaminants in rainbow trout (Oncorhynchus mykiss). We found that the delta(15)N and delta(13)C of food web components were related positively and significantly to sockeye salmon (Oncorhynchus nerka) spawner density. Contaminant concentrations in rainbow trout also positively and significantly were related to sockeye salmon spawner density. These data suggest that the anadromous salmon nutrient and contaminant pathways are related and significantly impact the contaminant burden of resident fish.

  20. Does bioleaching represent a biotechnological strategy for remediation of contaminated sediments?

    Energy Technology Data Exchange (ETDEWEB)

    Fonti, Viviana, E-mail: v.fonti@univpm.it; Dell' Anno, Antonio; Beolchini, Francesca

    2016-09-01

    Bioleaching is a consolidated biotechnology in the mining industry and in bio-hydrometallurgy, where microorganisms mediate the solubilisation of metals and semi-metals from mineral ores and concentrates. Bioleaching also has the potential for ex-situ/on-site remediation of aquatic sediments that are contaminated with metals, which represent a key environmental issue of global concern. By eliminating or reducing (semi-)metal contamination of aquatic sediments, bioleaching may represent an environmentally friendly and low-cost strategy for management of contaminated dredged sediments. Nevertheless, the efficiency of bioleaching in this context is greatly influenced by several abiotic and biotic factors. These factors need to be carefully taken into account before selecting bioleaching as a suitable remediation strategy. Here we review the application of bioleaching for sediment bioremediation, and provide a critical view of the main factors that affect its performance. We also discuss future research needs to improve bioleaching strategies for contaminated aquatic sediments, in view of large-scale applications. - Highlights: • Bioleaching may represent a sustainable strategy for contaminated dredged sediments • The performance is greatly influenced by several abiotic and biotic factors • Geochemical characteristics and metal partitioning have a key role • Sulphide minerals in the sediment are a favorable element • Microorganisms other than Fe/S oxidisers may open new perspectives.

  1. Does bioleaching represent a biotechnological strategy for remediation of contaminated sediments?

    International Nuclear Information System (INIS)

    Fonti, Viviana; Dell'Anno, Antonio; Beolchini, Francesca

    2016-01-01

    Bioleaching is a consolidated biotechnology in the mining industry and in bio-hydrometallurgy, where microorganisms mediate the solubilisation of metals and semi-metals from mineral ores and concentrates. Bioleaching also has the potential for ex-situ/on-site remediation of aquatic sediments that are contaminated with metals, which represent a key environmental issue of global concern. By eliminating or reducing (semi-)metal contamination of aquatic sediments, bioleaching may represent an environmentally friendly and low-cost strategy for management of contaminated dredged sediments. Nevertheless, the efficiency of bioleaching in this context is greatly influenced by several abiotic and biotic factors. These factors need to be carefully taken into account before selecting bioleaching as a suitable remediation strategy. Here we review the application of bioleaching for sediment bioremediation, and provide a critical view of the main factors that affect its performance. We also discuss future research needs to improve bioleaching strategies for contaminated aquatic sediments, in view of large-scale applications. - Highlights: • Bioleaching may represent a sustainable strategy for contaminated dredged sediments • The performance is greatly influenced by several abiotic and biotic factors • Geochemical characteristics and metal partitioning have a key role • Sulphide minerals in the sediment are a favorable element • Microorganisms other than Fe/S oxidisers may open new perspectives

  2. Innovative Capping Technology To Prevent The Migration of Toxic Chemicals From Contaminated Sediments

    Science.gov (United States)

    Capping is a common strategy for decreasing the risk associated with contaminated sediments in lakes and streams. Historically, caps have been designed to physically isolate contaminated sediments and prevent the transport of contaminants from sediments into the water above them...

  3. Pharmaceuticals and personal care products (PPCPs in the freshwater aquatic environment

    Directory of Open Access Journals (Sweden)

    Anekwe Jennifer Ebele

    2017-03-01

    Full Text Available Pharmaceuticals and personal care products (PPCPs are a unique group of emerging environmental contaminants, due to their inherent ability to induce physiological effects in human at low doses. An increasing number of studies has confirmed the presence of various PPCPs in different environmental compartments, which raises concerns about the potential adverse effects to humans and wildlife. Therefore, this article reviews the current state-of-knowledge on PPCPs in the freshwater aquatic environment. The environmental risk posed by these contaminants is evaluated in light of the persistence, bioaccumulation and toxicity criteria. Available literature on the sources, transport and degradation of PPCPs in the aquatic environment are evaluated, followed by a comprehensive review of the reported concentrations of different PPCP groups in the freshwater aquatic environment (water, sediment and biota of the five continents. Finally, future perspectives for research on PPCPs in the freshwater aquatic environment are discussed in light of the identified research gaps in current knowledge.

  4. Simulation of contaminated sediment transport in White Oak Creek basin

    International Nuclear Information System (INIS)

    Bao, Y.; Clapp, R.B.; Brenkert, A.L.; Moore, T.D.; Fontaine, T.A.

    1995-01-01

    This paper presents a systematic approach to management of the contaminated sediments in the White Oak Creek watershed at Oak Ridge National Laboratory near Oak Ridge, Tennessee. The primary contaminant of concern is radioactive cesium-137 ( 137 Cs), which binds to soil and sediment particles. The key components in the approach include an intensive sampling and monitoring system for flood events; modeling of hydrological processes, sediment transport, and contaminant flux movement; and a decision framework with a detailed human health risk analysis. Emphasis is placed on modeling of watershed rainfall-runoff and contaminated sediment transport during flooding periods using the Hydrologic Simulation Program- Fortran (HSPF) model. Because a large number of parameters are required in HSPF modeling, the major effort in the modeling process is the calibration of model parameters to make simulation results and measured values agree as closely as possible. An optimization model incorporating the concepts of an expert system was developed to improve calibration results and efficiency. Over a five-year simulation period, the simulated flows match the observed values well. Simulated total amount of sediment loads at various locations during storms match with the observed values within a factor of 1.5. Simulated annual releases of 137 Cs off-site locations match the data within a factor of 2 for the five-year period. The comprehensive modeling approach can provide a valuable tool for decision makers to quantitatively analyze sediment erosion, deposition, and transport; exposure risk related to radionuclides in contaminated sediment; and various management strategies

  5. Molecular diversity and tools for deciphering the methanogen community structure and diversity in freshwater sediments.

    Science.gov (United States)

    Chaudhary, Prem Prashant; Brablcová, Lenka; Buriánková, Iva; Rulík, Martin

    2013-09-01

    Methanogenic archaeal communities existing in freshwater sediments are responsible for approximately 50 % of the total global emission of methane. This process contributes significantly to global warming and, hence, necessitates interventional control measures to limit its emission. Unfortunately, the diversity and functional interactions of methanogenic populations occurring in these habitats are yet to be fully characterized. Considering several disadvantages of conventional culture-based methodologies, in recent years, impetus is given to molecular biology approaches to determine the community structure of freshwater sedimentary methanogenic archaea. 16S rRNA and methyl coenzyme M reductase (mcrA) gene-based cloning techniques are the first choice for this purpose. In addition, electrophoresis-based (denaturing gradient gel electrophoresis, temperature gradient gel electrophoresis, and terminal restriction fragment length polymorphism) and quantitative real-time polymerase chain reaction techniques have also found extensive applications. These techniques are highly sensitive, rapid, and reliable as compared to traditional culture-dependent approaches. Molecular diversity studies revealed the dominance of the orders Methanomicrobiales and Methanosarcinales of methanogens in freshwater sediments. The present review discusses in detail the status of the diversity of methanogens and the molecular approaches applied in this area of research.

  6. Temporal and spatial trends in sediment contaminants associated with toxicity in California watersheds

    International Nuclear Information System (INIS)

    Siegler, Katie; Phillips, Bryn M.; Anderson, Brian S.; Voorhees, Jennifer P.; Tjeerdema, Ron S.

    2015-01-01

    California's Stream Pollution Trends program (SPoT) assesses long-term water quality trends, using 100 base-of-the-watershed sampling sites. Annual statewide sediment surveys from 2008 to 2012 identified consistent levels of statewide toxicity (19%), using the freshwater amphipod Hyalella azteca. Significant contaminant trends included a decrease in PCBs, stable concentrations of metals and PAHs, and a statewide increase in detections and concentrations of pyrethroid pesticides. The pyrethroid pesticide bifenthrin was detected in 69% of samples (n = 410). Detection of toxicity increased in a subset of samples tested at a more environmentally relevant test temperature (15 °C), and the magnitude of toxicity was much greater, indicating pyrethroid pesticides as a probable cause. Pyrethroid toxicity thresholds (LC50) were exceeded in 83% of samples with high toxicity. Principal components analysis related pyrethroids, metals and total organic carbon to urban land use. - Highlights: • Toxicity and contaminant concentrations were higher in urban dominated watersheds. • Average and range of total pyrethroid concentrations increased between 2008 and 2012. • Pyrethroid toxicity thresholds (LC50) were exceeded in 83% of samples with high toxicity. - Detections and concentrations of current use pesticides are increasing in California urban watersheds, while legacy organochlorine contaminants are decreasing statewide.

  7. Declining metal levels at Foundry Cove (Hudson River, New York): Response to localized dredging of contaminated sediments

    International Nuclear Information System (INIS)

    Mackie, Joshua A.; Natali, Susan M.; Levinton, Jeffrey S.; Sanudo-Wilhelmy, Sergio A.

    2007-01-01

    This study examines the effectiveness of remediating a well-recognized case of heavy metal pollution at Foundry Cove (FC), Hudson River, New York. This tidal freshwater marsh was polluted with battery-factory wastes (1953-1979) and dredged in 1994-1995. Eight years after remediation, dissolved and particulate metals (Cd, Co, Cu, Pb, Ni, and Ag) were found to be lower than levels in the lower Hudson near New York City. Levels of metals (Co, Ni, Cd) on suspended particles were comparatively high. Concentrations of surface sediment Cd throughout the marsh system remain high, but have decreased both in the dredged and undredged areas: Cd was 2.4-230 mg/kg dw of sediment in 2005 vs. 109-1500 mg/kg in the same area in 1983. The rate of tidal export of Cd from FC has decreased by >300-fold, suggesting that dredging successfully stemmed a major source of Cd to the Hudson River. - Dredging of a hotspot of metal-contaminated sediment is associated with a recognizable local and river-wide decline in cadmium in the Hudson River, New York

  8. Performance testing of the sediment-contaminant transport model, SERATRA, at different rivers

    International Nuclear Information System (INIS)

    Onishi, Y.; Yabusaki, S.B.; Kincaid, C.T.

    1982-04-01

    Mathematical models of sediment-contaminant migration in surface water must account for transport, intermedia transfer, decay and degradation, and transformation processes. The unsteady, two dimensional, sediment-contaminant transport code, SERATRA (Onishi, Schreiber and Codell 1980) includes these mechanisms. To assess the accuracy of SERATRA to simulate the sediment-contaminant transport and fate processes, the code was tested against one-dimensional analytical solutions, checked for its mass balance, and applied to field sites. The field application cases ranged from relatively simple, steady conditions to unsteady, nonuniform conditions for large, intermediate, and small rivers. It was found that SERATRA is capable of simulating sediment-contaminant transport under a wide range of conditions

  9. IN SITU REMEDIATION OF CONTAMINATED SEDIMENTS - ACTIVE CAPPING TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A.; Roberts, J.; Paller, M.; Reible, D.

    2010-09-02

    Active capping is a relatively new approach for treating contaminated sediments. It involves applying chemically reactive amendments to the sediment surface. The main role of active caps is to stabilize contaminants in contaminated sediments, lower the bioavailable pool of contaminants, and reduce the release of contaminants to the water column. Metals are common contaminants in many marine and fresh water environments as a result of industrial and military activities. The mobile, soluble forms of metals are generally considered toxic. Induced chemical precipitation of these metals can shift toxic metals from the aqueous phase to a solid, precipitated phase which is often less bioavailable. This approach can be achieved through application of sequestering agents such as rock phosphates, organoclays, zeolites, clay minerals, and biopolymers (e.g., chitosan) in active capping technology. Active capping holds great potential for a more permanent solution that avoids residual risks resulting from contaminant migration through the cap or breaching of the cap. In addition to identifying superior active capping agents, research is needed to optimize application techniques, application rates, and amendment combinations that maximize sequestration of contaminants. A selected set of active capping treatment technologies has been demonstrated at a few sites, including a field demonstration at the Savannah River Site, Aiken, SC. This demonstration has provided useful information on the effects of sequestering agents on metal immobilization, bioavailability, toxicity, and resistance to mechanical disturbance.

  10. In Situ Remediation Of Contaminated Sediments - Active Capping Technology

    International Nuclear Information System (INIS)

    Knox, A.; Roberts, J.; Paller, M.; Reible, D.

    2010-01-01

    Active capping is a relatively new approach for treating contaminated sediments. It involves applying chemically reactive amendments to the sediment surface. The main role of active caps is to stabilize contaminants in contaminated sediments, lower the bioavailable pool of contaminants, and reduce the release of contaminants to the water column. Metals are common contaminants in many marine and fresh water environments as a result of industrial and military activities. The mobile, soluble forms of metals are generally considered toxic. Induced chemical precipitation of these metals can shift toxic metals from the aqueous phase to a solid, precipitated phase which is often less bioavailable. This approach can be achieved through application of sequestering agents such as rock phosphates, organoclays, zeolites, clay minerals, and biopolymers (e.g., chitosan) in active capping technology. Active capping holds great potential for a more permanent solution that avoids residual risks resulting from contaminant migration through the cap or breaching of the cap. In addition to identifying superior active capping agents, research is needed to optimize application techniques, application rates, and amendment combinations that maximize sequestration of contaminants. A selected set of active capping treatment technologies has been demonstrated at a few sites, including a field demonstration at the Savannah River Site, Aiken, SC. This demonstration has provided useful information on the effects of sequestering agents on metal immobilization, bioavailability, toxicity, and resistance to mechanical disturbance.

  11. Electrolysis-driven bioremediation of crude oil-contaminated marine sediments.

    Science.gov (United States)

    Bellagamba, Marco; Cruz Viggi, Carolina; Ademollo, Nicoletta; Rossetti, Simona; Aulenta, Federico

    2017-09-25

    Bioremediation is an effective technology to tackle crude oil spill disasters, which takes advantage of the capacity of naturally occurring microorganisms to degrade petroleum hydrocarbons under a range of environmental conditions. The enzymatic process of breaking down oil is usually more rapid in the presence of oxygen. However, in contaminated sediments, oxygen levels are typically too low to sustain the rapid and complete biodegradation of buried hydrocarbons. Here, we explored the possibility to electrochemically manipulate the redox potential of a crude oil-contaminated marine sediment in order to establish, in situ, conditions that are conducive to contaminants biodegradation by autochthonous microbial communities. The proposed approach is based on the exploitation of low-voltage (2V) seawater electrolysis to drive oxygen generation (while minimizing chlorine evolution) on Dimensionally Stable Anodes (DSA) placed within the contaminated sediment. Results, based on a laboratory scale setup with chronically polluted sediments spiked with crude oil, showed an increased redox potential and a decreased pH in the vicinity of the anode of 'electrified' treatments, consistent with the occurrence of oxygen generation. Accordingly, hydrocarbons biodegradation was substantially accelerated (up to 3-times) compared to 'non-electrified' controls, while sulfate reduction was severely inhibited. Intermittent application of electrolysis proved to be an effective strategy to minimize the energy requirements of the process, without adversely affecting degradation performance. Taken as a whole, this study suggests that electrolysis-driven bioremediation could be a sustainable technology for the management of contaminated sediments. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Chronic toxicity of sediment-associated linear alkylbenzene sulphonates (LAS) to freshwater benthic organisms

    Energy Technology Data Exchange (ETDEWEB)

    Comber, S.D.W. [WRc-NSF, Henley Road, Medmenham, Marlow, Buckinghamshire, SL7 2HD (United Kingdom)]. E-mail: sean.comber@atkinsglobal.com; Conrad, A.U. [Weinberg Group, Blue Tower, Box 16, B-1050 Brussels (Belgium); Hoess, S. [ECOSSA, Thierschstrasser 43, 80538, Muenchen (Germany); Webb, S. [CEFIC, Ave E. Van Nieuwenhuyse 4, B-1160 Brussels (Belgium); Marshall, S. [Unilever Research, Environment Centre, Bebington, Wirral, Merseyside, L63 3JW (United Kingdom)

    2006-11-15

    The toxicity of linear alkylbenzene sulphonates (LAS), to freshwater benthic organisms was assessed during exposure to spiked sediment. Lethal and sub-lethal end-points were monitored for two organisms (oligochaete Lumbriculus variegatus and nematode Caenorhabditis elegans). Results demonstrated relatively low toxicity (LOECs >100 mg/kg dry weight). No observed effect concentrations (NOECs) of 81 mg/kg dw (Lumbriculus) and 100 mg/kg dw (Caenorhabditis) were determined. For the oligochaete, no specific endpoint was particularly sensitive to LAS. For the nematode, egg production was the most sensitive endpoint. Significant degradation was measured over the 28-day duration of the Lumbriculus study, equating to a half-life of 20 days in sediment. - This paper provides sediment toxicity data for LAS, essential for a detailed and accurate environment risk assessment.

  13. Chronic toxicity of sediment-associated linear alkylbenzene sulphonates (LAS) to freshwater benthic organisms

    International Nuclear Information System (INIS)

    Comber, S.D.W.; Conrad, A.U.; Hoess, S.; Webb, S.; Marshall, S.

    2006-01-01

    The toxicity of linear alkylbenzene sulphonates (LAS), to freshwater benthic organisms was assessed during exposure to spiked sediment. Lethal and sub-lethal end-points were monitored for two organisms (oligochaete Lumbriculus variegatus and nematode Caenorhabditis elegans). Results demonstrated relatively low toxicity (LOECs >100 mg/kg dry weight). No observed effect concentrations (NOECs) of 81 mg/kg dw (Lumbriculus) and 100 mg/kg dw (Caenorhabditis) were determined. For the oligochaete, no specific endpoint was particularly sensitive to LAS. For the nematode, egg production was the most sensitive endpoint. Significant degradation was measured over the 28-day duration of the Lumbriculus study, equating to a half-life of 20 days in sediment. - This paper provides sediment toxicity data for LAS, essential for a detailed and accurate environment risk assessment

  14. Toxicity assessment of reference and natural freshwater sediments with the luminotox assay

    CSIR Research Space (South Africa)

    Dellamatrice, PM

    2006-08-01

    Full Text Available to exist between LuminoTox-Solid Phase Assay (Lum-SPA) and Microtox Solid Phase Assay (Mic-SPA) indicating that both tests display a similar toxicity response pattern for CRM sediments having differing contaminant profiles. The sediment elutriate Lum...

  15. The response of Scirpus pungens to crude oil contaminated sediments

    Energy Technology Data Exchange (ETDEWEB)

    Longpre, D; Jaouich, A [Quebec Univ., Montreal, PQ (Canada); Jarry, V [Environment Canada, Montreal, PQ (Canada); Venosa, A D [US Environmental Protection Agency, Cincinnati, OH (United States). National Risk Management Research Lab.; Lee, K [Fisheries and Oceans Canada, Mont Joli, PQ (Canada). Inst. Maurice Lamontagne; Suidan, M T [Cincinnati Univ., Cincinnati, OH (United States). Dept. of Civil and Environmental Engineering

    1999-01-01

    An exposure study was conducted to determine the impacts of an oil spill on the plant Scirpus pungens and to determine potential recovery rates of the species in the event of an accidental spill within the St. Lawrence River. Scirpus pungens is an important wetland plant which is essential for control of coastal erosion and which provides a unique habitat for a variety of biota. Sediments contaminated with medium-light crude oil were used in this study. Transplants in oiled and unoiled sediments were maintained in greenhouses to monitor changes in plant height, growth and mortality over a 63 day period. Results showed that plants exposed to high concentrations of oiled sediment were much smaller than those exposed to lightly contaminated sediments. Elevated oil concentrations greatly decreased plant biomass. Mortality was highly correlated with oil concentration. Transplants were able to survive, grow and produce new shoots in sediments contaminated with crude oil in a range of concentrations comparable to those associated with oil spills.

  16. The response of Scirpus pungens to crude oil contaminated sediments

    International Nuclear Information System (INIS)

    Longpre, D.; Jaouich, A.; Jarry, V.; Venosa, A.D.; Lee, K.; Suidan, M.T.

    1999-01-01

    An exposure study was conducted to determine the impacts of an oil spill on the plant Scirpus pungens and to determine potential recovery rates of the species in the event of an accidental spill within the St. Lawrence River. Scirpus pungens is an important wetland plant which is essential for control of coastal erosion and which provides a unique habitat for a variety of biota. Sediments contaminated with medium-light crude oil were used in this study. Transplants in oiled and unoiled sediments were maintained in greenhouses to monitor changes in plant height, growth and mortality over a 63 day period. Results showed that plants exposed to high concentrations of oiled sediment were much smaller than those exposed to lightly contaminated sediments. Elevated oil concentrations greatly decreased plant biomass. Mortality was highly correlated with oil concentration. Transplants were able to survive, grow and produce new shoots in sediments contaminated with crude oil in a range of concentrations comparable to those associated with oil spills

  17. Concentrations and compositions of organochlorine contaminants in sediments, soils, crustaceans, fishes and birds collected from Lake Tai, Hangzhou Bay and Shanghai city region, China

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, Haruhiko [Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan)]. E-mail: nakata@sci.kumamoto-u.ac.jp; Hirakawa, Yuko [Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Kawazoe, Masahiro [Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, (Japan); Nakabo, Tetsuji [Kyoto University Museum, Kyoto University, Sakyo-ku, Kyoto 606-8501 (Japan); Arizono, Koji [Faculty of Environmental and Symbiotic Sciences, Kumamoto Prefectural University, 3-1-100 Tsukide, Kumamoto 862-8502 (Japan); Abe, Shin-Ichi [Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Kitano, Takeshi [Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Shimada, Hideaki [Faculty of Education, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Watanabe, Izumi [Faculty of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchuu-city, Tokyo 183-8509 (Japan); Li Weihua [Shanghai Institute of Planned Parenthood Research, 2140 Xie Tu road, Shanghai 200032 (China); Ding Xucheng [Shanghai Institute of Planned Parenthood Research, 2140 Xie Tu road, Shanghai 200032 (China)

    2005-02-01

    Contamination by persistent organochlorines (OCs), such as DDTs, hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) were examined in sediments, soils, fishes, crustaceans, birds, and aquaculture feed from Lake Tai, Hangzhou Bay, and in the vicinity of Shanghai city in China during 2000 and 2001. OCs were detected in all samples analyzed, and DDT and its metabolites were the predominant contaminants in most sediments, soils and biota. Concentrations of p,p'-DDT and ratio of p,p'-DDT to {sigma}DDTs were significantly higher in marine fishes than those in freshwater fishes. While the use of DDTs has been officially banned in China since 1983, these results indicate a recent input of technical DDTs into the marine environment around Hangzhou Bay. Comparison of organochlorine concentrations in fishes collected from Lake Tai and Hangzhou Bay suggests the presence of local sources of HCHs, chlordanes and PCBs at Lake Tai. Higher proportions of penta- and hexa-PCB congeners in fishes at Lake Tai may suggest the use of highly chlorinated PCB product, such as PCB{sub 5}, around this lake. To our knowledge, this is a first comprehensive study to examine the present status of organochlorine contamination in various environmental media, such as sediments, soils and wildlife, in China. - Elevated concentrations of DDTs were detected in sediments, soils, and wildlife collected from China.

  18. Ammonium addition inhibits 13C-methane incorporation into methanotroph membrane lipids in a freshwater sediment

    NARCIS (Netherlands)

    Nold, S.C.; Boschker, H.T.S.; Pel, R.; Laanbroek, H.J.

    1999-01-01

    To investigate the effect of ammonium addition on the species composition and activity of freshwater methane oxidizing bacteria, intact sediment cores were labeled with 13CH4 and incubated under ambient and elevated ammonium concentrations. After 7 days, methanotroph activity was assessed by

  19. Effect of sulfate and nitrate on acetate conversion by anaerobic microorganisms in a freshwater sediment

    NARCIS (Netherlands)

    Scholten, J.C.M.; Bodegom, van P.M.; Vogelaar, J.; Ittersum, van A.; Hordijk, K.; Roelofsen, W.; Stams, A.J.M.

    2002-01-01

    Acetate is quantitatively the most important substrate for methane production in a freshwater sediment in The Netherlands. In the presence of alternative electron acceptors the conversion of acetate by methanogens was strongly inhibited. By modelling the results, obtained in experiments with and

  20. Environmental monitoring of Columbia River sediments: Grain-size distribution and contaminant association

    Energy Technology Data Exchange (ETDEWEB)

    Blanton, M.L.; Gardiner, W.W.; Dirkes, R.L.

    1995-04-01

    Based on the results of this study and literature review, the following conclusions can be made: Sediment grain size and TOC (total organic carbon) influence contaminant fate and transport (in general, sediments with higher TOC content and finer grain-size distribution can have higher contaminant burdens than sediments from a given river section that have less TOC and greater amounts of coarse-grained sediments). Physiochemical sediment characteristics are highly variable among monitoring sites along the Columbia River. Sediment grain characterization and TOC analysis should be included in interpretations of sediment-monitoring data.

  1. Environmental monitoring of Columbia River sediments: Grain-size distribution and contaminant association

    International Nuclear Information System (INIS)

    Blanton, M.L.; Gardiner, W.W.; Dirkes, R.L.

    1995-04-01

    Based on the results of this study and literature review, the following conclusions can be made: Sediment grain size and TOC (total organic carbon) influence contaminant fate and transport (in general, sediments with higher TOC content and finer grain-size distribution can have higher contaminant burdens than sediments from a given river section that have less TOC and greater amounts of coarse-grained sediments). Physiochemical sediment characteristics are highly variable among monitoring sites along the Columbia River. Sediment grain characterization and TOC analysis should be included in interpretations of sediment-monitoring data

  2. Assessing sediment contamination using six toxicity assays

    OpenAIRE

    Allen G. BURTON Jr.; Carolyn ROWLAND; Renato BAUDO; Monica BELTRAMI

    2001-01-01

    An evaluation of sediment toxicity at Lake Orta, Italy was conducted to compare a toxicity test battery of 6 assays and to evaluate the extent of sediment contamination at various sediment depths. Lake Orta received excessive loadings of copper and ammonia during the 1900’s until a large remediation effort was conducted in 1989-90 using lime addition. Since that time, the lake has shown signs of a steady recovery of biological communities. The study results showed acute toxicity still exists ...

  3. Equilibrium sampling for a thermodynamic assessment of contaminated sediments

    DEFF Research Database (Denmark)

    Mayer, Philipp; Nørgaard Schmidt, Stine; Mäenpää, Kimmo

    Hydrophobic organic contaminants (HOCs) reaching the aquatic environment are largely stored in sediments. The risk of contaminated sediments is challenging to assess since traditional exhaustive extraction methods yield total HOC concentrations, whereas freely dissolved concentrations (Cfree......) govern diffusive uptake and partitioning. Equilibrium sampling of sediment was introduced 15 years ago to measure Cfree, and it has since developed into a straightforward, precise and sensitive approach for determining Cfree and other exposure parameters that allow for thermodynamic assessment...... of polluted sediments. Glass jars with µm-thin silicone coatings on the inner walls can be used for ex situ equilibration while a device housing several silicone-coated fibers can be used for in situ equilibration. In both cases, parallel sampling with varying silicone thicknesses can be applied to confirm...

  4. Seasonal Changes in Microbial Community Structure in Freshwater Stream Sediment in a North Carolina River Basin

    Directory of Open Access Journals (Sweden)

    John P. Bucci

    2014-01-01

    Full Text Available This study examined seasonal differences in microbial community structure in the sediment of three streams in North Carolina’s Neuse River Basin. Microbes that reside in sediment are at the base of the food chain and have a profound influence on the health of freshwater stream environments. Terminal-Restriction Fragment Length Polymorphism (T-RFLP, molecular fingerprint analysis of 16S rRNA genes was used to examine the diversity of bacterial species in stream sediment. Sediment was sampled in both wet and dry seasons from an agricultural (Bear, mixed urban (Crabtree and forested (Marks Creek, and the microbiota examined. Gamma, Alpha and Beta proteobacteria were prevalent species of microbial taxa represented among all sites. Actinobacteria was the next most prevalent species observed, with greater occurrence in dry compared to the wet season. Discernable clustering was observed of Marks and Bear Creek samples collected during the wetter period (September–April, which corresponded with a period of higher precipitation and cooler surface water temperatures. Although not statistically significant, microbial community structure appeared different between season (ANOSIM, R = 0.60; p < 0.10. Principal components analysis confirmed this pattern and showed that the bacterial groups were separated by wet and dry seasonal periods. These results suggest seasonal differences among the microbial community structure in sediment of freshwater streams and that these communities may respond to changes in precipitation during wetter periods.

  5. Ammonium addition inhibits 13C-methane incorporation into methanotroph membrane lipids in a freshwater sediment

    NARCIS (Netherlands)

    Nold, s.c.; Boschker, H.T.S.; Pel, R.; Laanbroek, H.J.

    1999-01-01

    To investigate the effect of ammonium addition on the species composition and activity of freshwater methane oxidizing bacteria, intact sediment cores were labeled with (CH4)-C-13 and incubated under ambient and elevated ammonium concentrations. After 7 days, methanotroph activity was assessed by

  6. Coal tar phototherapy for psoriasis reevaluated: erythemogenic versus suberythemogenic ultraviolet with a tar extract in oil and crude coal tar

    International Nuclear Information System (INIS)

    Lowe, N.J.; Wortzman, M.S.; Breeding, J.; Koudsi, H.; Taylor, L.

    1983-01-01

    Recent studies have questioned the therapeutic value of coal tar versus ultraviolet (UV) radiation and their relative necessity in phototherapy for psoriasis. In this investigation, different aspects of tar phototherapy have been studied in single-blind bilateral paired comparison studies. The effects of 1% crude coal tar were compared with those of petrolatum in conjunction with erythemogenic and suberythemogenic doses of ultraviolet light (UVB) using a FS72 sunlamp tubed cabinet. Crude coal tar was clinically superior to petrolatum with suberythemogenic ultraviolet. With the erythemogenic UVB, petrolatum was equal in efficacy to crude coal tar. Suberythemogenic UVB was also used adjunctively to compare the effects of a 5% concentration of a tar extract in an oil base to 5% crude coal tar in petrolatum or the oil base without tar. The tar extract in oil plus suberythemogenic UVB produced significantly more rapid improvement than the oil base plus UVB. The direct bilateral comparison of equal concentrations of tar extract in oil base versus crude coal tar in petrolatum in a suberythemogenic UV photo regimen revealed no statistical differences between treatments. In a study comparing tar extract in oil and the oil base without ultraviolet radiation, the tar extract in oil side responded more rapidly

  7. An evaluation of contaminated estuarine sites using sediment quality guidelines and ecological assessment methodologies.

    Science.gov (United States)

    Fulton, M; Key, P; Wirth, E; Leight, A K; Daugomah, J; Bearden, D; Sivertsen, S; Scott, G

    2006-10-01

    Toxic contaminants may enter estuarine ecosystems through a variety of pathways. When sediment contaminant levels become sufficiently high, they may impact resident biota. One approach to predict sediment-associated toxicity in estuarine ecosystems involves the use of sediment quality guidelines (ERMs, ERLs) and site-specific contaminant chemistry while a second approach utilizes site-specific ecological sampling to assess impacts at the population or community level. The goal of this study was to utilize an integrated approach including chemical contaminant analysis, sediment quality guidelines and grass shrimp population monitoring to evaluate the impact of contaminants from industrial sources. Three impacted sites and one reference site were selected for study. Grass shrimp populations were sampled using a push-netting approach. Sediment samples were collected at each site and analyzed for metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and pesticides. Contaminant levels were then compared to sediment quality guidelines. In general, grass shrimp population densities at the sites decreased as the ERM quotients increased. Grass shrimp densities were significantly reduced at the impacted site that had an ERM exceedance for chromium and the highest Mean ERM quotient. Regression analysis indicated that sediment chromium concentrations were negatively correlated with grass shrimp density. Grass shrimp size was reduced at two sites with intermediate levels of contamination. These findings support the use of both sediment quality guidelines and site-specific population monitoring to evaluate the impacts of sediment-associated contaminants in estuarine systems.

  8. Estimating release of polycyclic aromatic hydrocarbons from coal tar at manufactured-gas plant sites

    International Nuclear Information System (INIS)

    Loehr, R.C.; Rao, P.S.C.; Lee, L.S.; Okuda, I.

    1992-08-01

    One component of the EPRI's research on Envirorunental Behavior of Organic Substances (EBOS) consists of developing information and models to predict releases of monocyclic and polycyclic aromatic hydrocarbons (MAHs and PAHs) to groundwater from coal tars and contaminated soils at MGP sites. The results of this report focus primarily on release of PAHs from coal tars. There are at least two approaches to predicting the release of organic chemicals from coal tar to water. The simplest method to estimate aqueous concentrations is to assume that water solubility of a PAH compound released from the tar can be defined by equilibrium precipitation-dissolution reactions. Application of Raoult's law is another method to predict aqueous concentrations, which requires the assumption of ''ideal'' behavior for partitioning of PAHs between the tar and water phases. To evaluate the applicability of these two methods for predicting PAH releases, laboratory experiments were conducted with eight coal tar samples from former MGP sites across the country. Migration of chemicals in the environment and resulting contaminant plumes in groundwater are determined by leachate concentrations of the chemicals. The use of equilibrium precipitation-dissolution reactions will usually result in an overestimation of PAH concentrations in the leachate from a coal tar source, and thus the resulting PAH concentrations in groundwater. Raoult's law appears to be a more accurate approach to predicting the release of several PAHs from coal tars. Furthermore, if nonequilibrium conditions prevail, aqueous-phase PAH concentrations will be even lower than those predicted using Raoult's law

  9. Passive sampling methods for contaminated sediments: State of the science for organic contaminants

    Science.gov (United States)

    Lydy, Michael J; Landrum, Peter F; Oen, Amy MP; Allinson, Mayumi; Smedes, Foppe; Harwood, Amanda D; Li, Huizhen; Maruya, Keith A; Liu, Jingfu

    2014-01-01

    This manuscript surveys the literature on passive sampler methods (PSMs) used in contaminated sediments to assess the chemical activity of organic contaminants. The chemical activity in turn dictates the reactivity and bioavailability of contaminants in sediment. Approaches to measure specific binding of compounds to sediment components, for example, amorphous carbon or specific types of reduced carbon, and the associated partition coefficients are difficult to determine, particularly for native sediment. Thus, the development of PSMs that represent the chemical activity of complex compound–sediment interactions, expressed as the freely dissolved contaminant concentration in porewater (Cfree), offer a better proxy for endpoints of concern, such as reactivity, bioaccumulation, and toxicity. Passive sampling methods have estimated Cfree using both kinetic and equilibrium operating modes and used various polymers as the sorbing phase, for example, polydimethylsiloxane, polyethylene, and polyoxymethylene in various configurations, such as sheets, coated fibers, or vials containing thin films. These PSMs have been applied in laboratory exposures and field deployments covering a variety of spatial and temporal scales. A wide range of calibration conditions exist in the literature to estimate Cfree, but consensus values have not been established. The most critical criteria are the partition coefficient between water and the polymer phase and the equilibrium status of the sampler. In addition, the PSM must not appreciably deplete Cfree in the porewater. Some of the future challenges include establishing a standard approach for PSM measurements, correcting for nonequilibrium conditions, establishing guidance for selection and implementation of PSMs, and translating and applying data collected by PSMs. Integr Environ Assess Manag 2014;10:167–178. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of

  10. Seed dormancy and persistent sediment seed banks of ephemeral freshwater rock pools in the Australian monsoon tropics.

    Science.gov (United States)

    Cross, Adam T; Turner, Shane R; Renton, Michael; Baskin, Jerry M; Dixon, Kingsley W; Merritt, David J

    2015-04-01

    Rock pools are small, geologically stable freshwater ecosystems that are both hydrologically and biologically isolated. They harbour high levels of plant endemism and experience environmental unpredictability driven by the presence of water over variable temporal scales. This study examined the hypothesis that the sediment seed bank in monsoon tropical freshwater rock pools would persist through one or more periods of desiccation, with seed dormancy regulating germination timing in response to rock pool inundation and drying events. Seeds were collected from seven dominant rock pool species, and germination biology and seed dormancy were assessed under laboratory conditions in response to light, temperature and germination stimulators (gibberellic acid, karrikinolide and ethylene). Field surveys of seedling emergence from freshwater rock pools in the Kimberley region of Western Australia were undertaken, and sediment samples were collected from 41 vegetated rock pools. Seedling emergence and seed bank persistence in response to multiple wetting and drying cycles were determined. The sediment seed bank of individual rock pools was large (13 824 ± 307 to 218 320 ± 42 412 seeds m(-2) for the five species investigated) and spatially variable. Seedling density for these same species in the field ranged from 13 696 to 87 232 seedlings m(-2). Seeds of rock pool taxa were physiologically dormant, with germination promoted by after-ripening and exposure to ethylene or karrikinolide. Patterns of seedling emergence varied between species and were finely tuned to seasonal temperature and moisture conditions, with the proportions of emergent seedlings differing between species through multiple inundation events. A viable seed bank persisted after ten consecutive laboratory inundation events, and seeds retained viability in dry sediments for at least 3 years. The persistent seed bank in freshwater rock pools is likely to provide resilience to plant

  11. Radioactivity of the Bega sediment-case study of a contaminated canal

    International Nuclear Information System (INIS)

    Bikit, I.; Varga, E.; Conkic, Lj.; Slivka, J.; Mrda, D.; Curcic, S.; Zikic-Todorovic, N.; Veskovic, M.

    2005-01-01

    The Bega canal is one among many heavily polluted canals in Vojvodina (the northern province of Serbia and Montenegro). In the framework of the revitalization of this canal, the radionuclide content of the sediment was investigated in order to support the safe deposition after excavation. It was found that, in comparison with the Danube sediment and Vojvodina soil, the Bega sediment is contaminated with 238 U and 137 Cs. The origin of this contamination is discussed. No traces of contamination by nuclear power plants in the region were found, while the presence of technologically enhanced, natural occurring radioactive materials (TENORM) was proved

  12. Contaminant bioavailability in soils, sediments, and aquatic environments

    OpenAIRE

    Traina, Samuel J.; Laperche, Valérie

    1999-01-01

    The aqueous concentrations of heavy metals in soils, sediments, and aquatic environments frequently are controlled by the dissolution and precipitation of discrete mineral phases. Contaminant uptake by organisms as well as contaminant transport in natural systems typically occurs through the solution phase. Thus, the thermodynamic solubility of contaminant-containing minerals in these environments can directly influence the chemical reactivity, transport, and ecotoxici...

  13. Methane Bubbles Transport Particles From Contaminated Sediment to a Lake Surface

    Science.gov (United States)

    Delwiche, K.; Hemond, H.

    2017-12-01

    Methane bubbling from aquatic sediments has long been known to transport carbon to the atmosphere, but new evidence presented here suggests that methane bubbles also transport particulate matter to a lake surface. This transport pathway is of particular importance in lakes with contaminated sediments, as bubble transport could increase human exposure to toxic metals. The Upper Mystic Lake in Arlington, MA has a documented history of methane bubbling and sediment contamination by arsenic and other heavy metals, and we have conducted laboratory and field studies demonstrating that methane bubbles are capable of transporting sediment particles over depths as great as 15 m in Upper Mystic Lake. Methane bubble traps were used in-situ to capture particles adhered to bubble interfaces, and to relate particle mass transport to bubble flux. Laboratory studies were conducted in a custom-made 15 m tall water column to quantify the relationship between water column height and the mass of particulate transport. We then couple this particle transport data with historical estimates of ebullition from Upper Mystic Lake to quantify the significance of bubble-mediated particle transport to heavy metal cycling within the lake. Results suggest that methane bubbles can represent a significant pathway for contaminated sediment to reach surface waters even in relatively deep water bodies. Given the frequent co-occurrence of contaminated sediments and high bubble flux rates, and the potential for human exposure to heavy metals, it will be critical to study the significance of this transport pathway for a range of sediment and contaminant types.

  14. The assessment of sediment contamination in an acid mine drainage impacted river in Gauteng (South Africa) using three sediment bioassays

    OpenAIRE

    2015-01-01

    M.Sc. (Zoology) Sediment contamination occurs as a result of various anthropogenic activities; mainly through mining-, agricultural- and industrial practices. Many of the contaminants arising from these activities enter the aquatic system and precipitate from the surrounding water, binding to sediment particles. In the sediment compartment, these contaminants reach concentrations much higher than in solution with the overlying water. Even though the quality of the overlying water may prove...

  15. Passive sampling methods for contaminated sediments

    DEFF Research Database (Denmark)

    Peijnenburg, Willie J.G.M.; Teasdale, Peter R.; Reible, Danny

    2014-01-01

    “Dissolved” concentrations of contaminants in sediment porewater (Cfree) provide a more relevant exposure metric for risk assessment than do total concentrations. Passive sampling methods (PSMs) for estimating Cfree offer the potential for cost-efficient and accurate in situ characterization...

  16. The influence of sulfate and nitrate on the methane formation by methanogenic archaea in freshwater sediments

    OpenAIRE

    Scholten, J.C.M.

    1999-01-01

    In this thesis the effect of inorganic electron acceptors (sulfate and nitrate) on methane emission from freshwater sediments in the Netherlands was investigated. The chosen study area was a polder located between Leiden and Utrecht, and is representative for similar polders in The Netherlands (Chapter 3). The polder contains peat grasslands in which ditches are lying used for maintaining stable water levels. The ditches contain sediment which is a potential source of C...

  17. Assessment of heavy metal contamination in the sediment of the River Ghaghara, a major tributary of the River Ganga in Northern India

    Science.gov (United States)

    Singh, Harendra; Pandey, Ruby; Singh, Sudhir Kumar; Shukla, D. N.

    2017-11-01

    The present study includes a systematic analysis of sediment contamination by heavy metals of the River Ghaghara flowing through the Uttar Pradesh and Bihar in Indian Territory. To estimate the geochemical environment of the river, seven heavy metals, namely Co, Cu, Cr, Ni, Cd, Zn, and Pb were examined from the freshly deposited river bed sediment. All the sediment samples were collected on a seasonal basis for the assessment of fluctuation in 2014-2015 and after preparation samples were analyzed using standard procedure. Result showed that heavy metal concentration ranged between 11.37 and 18.42 mg/kg for Co, 2.76 and 11.74 mg/kg for Cu, 61.25 and 87.68 mg/kg for Cr, 15.29 and 25.59 mg/kg for Ni, 0.21 and 0.28 mg/kg for Cd, 13.26 and 17.59 mg/kg for Zn, 10.71 and 14.26 mg/kg for Pb in different season. Metal contamination factor indicates the anthropogenic input in the river sediment was in the range of (0.62-0.97) for Co, (0.04-0.26) for Cu, (0.68-0.97) for Cr, (0.22-0.38) for Ni, (0.70-0.93) for Cd, (0.14-0.19) for Zn, and (0.54-0.71) for Pb. The highest contamination degree of the sediment was noticed as 4.01 at Ayodhya and lowest as 3.16 at Katerniaghat. Geo-accumulation index was noted between (0 and 1) which showed that sediment was uncontaminated to moderately contaminated and may have adverse affects on freshwater ecology of the river. Pollution load index (PLI) was found highest at Chhapra which was 0.45 and lowest at Katerniaghat which was 0.35 and it indicates that the river sediment has a low level of contamination. Significant high correlation was observed between Co, Cu, and Zn, it suggests same source of contamination input is mainly due to human settlement and agriculture activity. Positive correlation between Zn, Co, Cu, Cr, and Ni indicated a natural origin of these elements in the river sediment. Cluster analysis suggests grouping of similar polluted sites. The strong similarity between Co, Zn, Pb, Ni, Cu, and Cd showed relationship of these

  18. The effect of activated carbon on partitioning, desorption, and biouptake of native polychlorinated biphenyls in four freshwater sediments.

    Science.gov (United States)

    Sun, Xueli; Ghosh, Upal

    2008-11-01

    The present study evaluated the effect of activated carbon amendment in four freshwater sediments from the Great Lakes (North America) areas of concern with a wide range of sediment geochemical characteristics (0.83-5.1% total organic carbon) and polychlorinated biphenyl (PCB) concentrations (0.33-84.7 microg/g). The work focused on understanding the impact of activated carbon amendment on PCB aqueous partitioning, PCB desorption characteristics, and PCB biouptake in a freshwater oligochaete (Lumbriculus variegatus). The results showed that PCB aqueous equilibrium concentrations, rapid desorption fractions, and biouptake by the oligochaete were reduced after activated carbon amendment. Addition of activated carbon at a dose of 0.5-fold native organic carbon reduced PCB bioaccumulation by 42% for Niagara River sediment, 85% for Grasse River sediment, 74% for Milwaukee River sediment 1, and 70% for Milwaukee River sediment 2. A linear relationship was observed between log biota-sediment accumulation factor and the first 6-h desorption fractions for each PCB homologue for treated and untreated sediments. Water-lipid bioconcentration factors for PCB congeners were largely conserved after amendment with activated carbon. Our present results suggest that at steady state, changes in the aqueous PCB concentrations can be used to predict changes in PCB bioaccumulation in deposit-feeding organisms. Thus, use of advanced pore-water measurement techniques, such as solid-phase extraction passive samplers, may be suitable for long-term monitoring of treatment performance.

  19. Potential risks of metal toxicity in contaminated sediments of Deule river in Northern France

    International Nuclear Information System (INIS)

    Lourino-Cabana, Beatriz; Lesven, Ludovic; Charriau, Adeline; Billon, Gabriel; Ouddane, Baghdad; Boughriet, Abdel

    2011-01-01

    Research highlights: → A historical environmental pollution is evidenced with reference to background levels. → Sedimentary trace metals partitioning is examined under undisturbed conditions. → Anoxia and diagenetic processes induce geochemical and mineralogical variabilities. → Do metals present in particles and pore waters exhibit a potential toxicity risk? → Behaviour of binding fractions contributes to trace metals scavenging. - Abstract: The aim of this paper was to evaluate the potential sediment cumulative damage and toxicity due to metal contamination in a polluted zone of Deule river (in northern France) from nearby two smelters. Metal-enrichment factors and geoaccumulation indices measured with sediment depth revealed that - compared to background levels either in local reference soils or in world rivers sediments/suspended particulate matter - Cd contributed to the highest pollution levels, followed by Zn, Pb and to a much lesser extent Cu and Ni. A comparison of the vertical distribution of AVS (acid volatile sulfides), SEM (simultaneously extracted metals), TMC (total metal concentrations), TOC (total organic carbon) and interstitial water-metal concentrations in the sediment allowed us to highlight the extent of toxicity caused by Cd, Pb, Zn, Ni and Cu and to raise the possibility of their association with certain geochemical phases. To assess the actual environmental impacts of these metals in Deule river, numerical sediment quality guidelines were further used in the present work. Sedimentary Pb, Zn, and Cd contents largely exceeded PEC (probable effect concentration) values reported as consensus-based sediment quality guidelines for freshwater ecosystems. As for risks of toxicity from pore waters, metal concentrations reached their maxima at the surficial layers of the sediment (1-3 cm) and IWCTU (Interstitial Water Criteria Toxicity Unit) observed for Pb and to a lesser extent Cd, violated the corresponding water quality data recommended

  20. Sources of heavy metals in sediments of the Hudson River Estuary

    International Nuclear Information System (INIS)

    Williams, S.C.; Simpson, H.J.; Olsen, C.R.; Bopp, R.F.

    1978-01-01

    Sediments in the Hudson Estuary contain zinc, copper and lead from metal pollutants discharged to the harbor in the New York City area, from dispersed sources of contamination introduced upstream, and from natural weathering processes. The magnitude of the contribution from each of these three sources to particular sites can be estimated on the basis of total metal abundances, relative proportions of several metals, and other sediment properties. The pattern of recent heavy-metal contamination in Hudson sediments closely follows the distribution in sediments of 137 Cs which was derived over the past two decades from global fallout and local releases from a commercial nuclear reactor. Several simple empirical corrections related to grain size and mineralogy variations are suggested for comparing heavy-metal contamination levels of sandy continental shelf sediments with fine-grained estuarine and coastal sediments. Iron has little variation in Hudson sediments while manganese is greater in surface sediment of some low-salinity and fresh-water areas than deeper in the sediments, and generally less in the high-salinity area of rapid sediment deposition in New York harbor. Much of the pollutant Cu added to the harbor appears to be rapidly deposited in the sediments. (Auth.)

  1. Geophysical characterization of contaminated muddy sediments

    International Nuclear Information System (INIS)

    McDermott, I. R.; English, G. E.

    1997-01-01

    A non-intrusive, seismic subbottom profile survey of pond sediments was conducted on a former U.S.Naval Facility at Argentia, Newfoundland, to characterize the nature and extent of contamination. An IKB Seistec boomer was used in conjunction with C-CORE's HI-DAPT digital data acquisition and processing system and differential GPS system. The survey was successful in locating regions of soft muddy sediments and in determining the thickness of these deposits. Subsurface buried objects, which are potential sources of pollution, were also identified. Intrusive profiling of the sediment was done with a new tool, the Soil Stiffness Probe, which combines two geophysical measurement systems to determine bulk density and shear stiffness. The muddy sediments were found to be highly 'fluidized', indicating that they could be easily removed with a suction dredge. 4 refs., 5 figs

  2. TBT-contaminated sediments. Treatment in a pilot scale

    Energy Technology Data Exchange (ETDEWEB)

    Stichnothe, H.; Calmano, W.; Arevalo, E.; Keller, A.; Thoeming, J. [Hamburg Univ. of Technology, Dept. Environmental Science and Technology, Hamburg (Germany)

    2005-07-01

    Background, aims and scope. Sediments in harbours and nearby shipyards demonstrate widespread contamination with tributyltin (TBT). Therefore, reuse and relocation of dredged material from these locations are prohibited. Even if the international marine organization (IMO) convention concerning TBT-based paints is ratified (champ 2003) the TBT problem in sediments will continue to remain for many years due to the persistence of TBT. Methods. An electrochemical process has been developed to treat polluted sediments. Dredged materials with high and low TBT-contents were studied on a technical and a pilot scale. The treatment process was assessed by chemical analysis and a biotest battery. Additionally, an economic analysis was performed to check the economic feasibility of the process to treat dredged material from two different locations at different operating conditions. Furthermore an up-scaling estimation was performed to evaluate treatment costs at a larger scale, i.e. for a plant having a capacity of 720,000 t/a. Results and discussion. Butyltin species and polycyclic aromatic hydrocarbons (PAH) were decomposed due to electrochemically-induced oxidation, while the treatment did not alter heavy metal and PCB concentrations. The bacteria luminescence test indicated a reduced toxicity after the electrochemical treatment, while the algae growth inhibition test and bacteria contact test did not confirm these results. Based on a small consumer price of Euro 0.12/kWh, treating the high-contaminated sediment in the pilot plant would cost Euro 21/m{sup 3} and Euro 31/m{sup 3} for the low contaminated sediment, respectively. Assuming an industrial consumer price of Euro 0.06/kWh for electricity in an up-scaled process with a capacity of 720,000 t/a, the total treatment costs for the low contaminated sediment would be Euro 13/m{sup 3}. Conclusion. The results of treating dredged material from Bremerhaven and the fine-grained fraction from the METHA plant show that the

  3. Heavy metal contamination of soil and sediment in Zambia

    African Journals Online (AJOL)

    USER

    Key words: Heavy metal, contamination, mining, soil, sediment. INTRODUCTION ... drinking water and inhaling air or soil contaminated by mining activities and the ..... indicates that copper waste discharged into the upper reaches of the Kafue ...

  4. A DEVICE AND METHOD FOR MEASURING TAR IN A TAR-ENVIRONMENT

    DEFF Research Database (Denmark)

    2017-01-01

    The present disclosure describes a device and corresponding method for measuring tar in a tar environment, e.g., a tar producing environment such as a stove or a combustion engine, based on UV absorption spectroscopy. A first measurement along an optical path in the tar environment is performed...

  5. The influence of sulfate and nitrate on the methane formation by methanogenic archaea in freshwater sediments

    NARCIS (Netherlands)

    Scholten, J.C.M.

    1999-01-01

    In this thesis the effect of inorganic electron acceptors (sulfate and nitrate) on methane emission from freshwater sediments in the Netherlands was investigated. The chosen study area was a polder located between Leiden and Utrecht, and is representative for similar polders

  6. Survival of Salmonella enterica in Freshwater and Sediments and Transmission by the Aquatic Midge Chironomus tentans (Chironomidae: Diptera)

    Science.gov (United States)

    Moore, Barry C.; Martinez, Edward; Gay, John M.; Rice, Daniel H.

    2003-01-01

    Survival of a nalidixic acid-resistant strain of Salmonella enterica serovar Typhimurium mr-DT-104 in water and sediments was tested using artificially contaminated aquaria. Water samples remained culture positive for salmonella for up to 54 days. Sediment samples were culture positive up to 119 days. In addition, potential mechanisms for spreading salmonella in the environments by chironomid larvae and adults were tested. We evaluated the acquisition of mr-DT-104 by chironomids from contaminated aquatic sediments and subsequent spread to uncontaminated sediments. Larval chironomids raised in contaminated sediments became culture positive, and the bacteria were carried over to adults after emergence. Contamination of clean sediments by chironomid larvae was not demonstrated. These findings clearly suggest that mr-DT-104 serovar organisms can survive in aquatic sediments for at least several months. Uptake of salmonellae by chironomid larvae and adults suggests that they are possible vectors of mr-DT-104 in both aquatic and terrestrial environments, although the role of larval defecation in movement of bacteria to new sediments was not demonstrated. PMID:12902242

  7. Studies on the applicability of biomarkers in estimating the systematic bioavailability of polynuclear aromatic hydrocarbons from manufactured gas plant tar-contaminated soils

    International Nuclear Information System (INIS)

    Koganti, A.; Spina, D.A.; Rozett, K.; Ma, B.-L.; Weyand, E.; Taylor, B.B.; Mauro, D.M.

    1998-01-01

    The systematic bioavailability of polynuclear aromatic hydrocarbons (PAH) from ingested soils containing manufactured gas plant (MGP) tar was evaluated in mice. Soil and organic extract of each soil were incorporated into a diet and fed to mice for two weeks. 1-Hydroxypyrene levels in urine and chemical:DNA adduct levels in lungs were used as biomarkers of PAH systematic bioavailability. Estimates of PAH relative bioavailability were determined by comparing the bioavailability observed between each soil and corresponding organic extract. In all but one case, bioavailiablity estimates based on 1-hydroxypyrene levels in urine indicate that the presence of MGP tar on soil results in a considerable decrease in PAH systemic bioavailablity (9-75%). Similarly, PAH bioavailability estimates based on chemical:DNA adduct formation ranged from nondetectable to 76%. These results clearly indicate that the bioavailiablity of PAH is less than 100% when soil contaminated with MGP tar is ingested by nice. In addition, the experimental methods employed in this study appear suitable for evaluating the effects of soil on the gastrointestinal absorption and systemic bioavailability of PAH from soil containing complex organic mixtures. 44 refs., 1 fig., 5 tabs

  8. Effects of petroleum and metal contaminated soil on plants and earthworms: Survival and bioaccumulation

    International Nuclear Information System (INIS)

    Tatem, H.E.; Simmers, J.W.; Skogerboe, J.G.; Lee, C.R.

    1993-01-01

    Earthworms, Eisenia foetida, and bermudagrass, Cynodon dactylon, were used in the laboratory to test the toxicity of contaminated sediment taken from a small fresh water lake in North Carolina. This work was part of an investigation to determine the potential effects of upland disposal of this sediment. The contaminated sediment contained As, Cr, Cu, Pb, Hg, Ni, Zn and petroleum hydrocarbons at concentrations much greater than nearby soils. Test cylinders were planted with bermudagrass; earthworms were added 30 days later. Both species were harvested at 60 days, weighed and submitted for chemical analyses. Cynodon was affected by the contaminated sediment but grew well in the mixtures of sediment and upland soil. Similar results were obtained with the Eisenia. These species did not accumulate hydrocarbons from the sediment with the possible exception of pyrene. The metals Cd, Pb, and Zn were elevated in plants exposed to the contaminated sediment. Earthworms exposed to this sediment accumulated Pb to concentrations greater than animals exposed to the manure control. This work demonstrated that a contaminated freshwater sediment was not toxic to plants or earthworms and that most petroleum hydrocarbons were not accumulated. The only metal that may be of some concern was Pb

  9. Evaluating a 5-year metal contamination remediation and the biomonitoring potential of a freshwater gastropod along the Xiangjiang River, China.

    Science.gov (United States)

    Li, Deliang; Pi, Jie; Zhang, Ting; Tan, Xiang; Fraser, Dylan J

    2018-05-16

    Effective remediation of heavy metal pollution in aquatic systems is desired in many regions, but it requires integrative assessments of sediments, water, and biota that can serve as robust biomonitors. We assessed the effects of a 5-year metal contamination remediation along the Xiangjiang River, China, by comparing concentrations of trace metals in water and surface sediments between 2010-2011 and 2016. We also explored the trace metal biomonitoring potential of a freshwater gastropod (Bellamya aeruginosa). Metal concentrations in water (means and ranges) dropped over time to within permissible limits of drinking water guidelines set by China, USEPA, and WHO in 2016. Although sediment means and ranges of Cd, Pb, Zn, and Mn also diminished with remediation, those for Cr and Cu slightly increased, and all six metals retained concentrations higher than standards set by China. All metals in sediments could also be associated with anthropogenic inputs using a hierarchical clustering analysis, and they generate high potential ecological risks based on several indices, especially for Cd and As. The bio-sediment accumulation factors of all measured trace metals in gastropod soft tissues and shells were lower than 1.0, except for Ca. Trace metal contents in gastropods were positively correlated with those in water and surface sediments for As (soft tissues) and Cr (shells). Collectively, our results do not yet highlight strong beneficial effects of 5-year remediation and clearly illustrate the heavy metal pollution remaining in Xiangjiang River sediment. Additional physical, chemical, and biological measurements should be implemented to improve sediment quality. We further conclude that gastropod soft tissues and shells can be suitable biomonitors of spatial differences in some heavy metals found within river sediments (e.g., As, Cr).

  10. Human health risk assessment in relation to environmental pollution of two artificial freshwater lakes in The Netherlands.

    Science.gov (United States)

    Albering, H J; Rila, J P; Moonen, E J; Hoogewerff, J A; Kleinjans, J C

    1999-01-01

    A human health risk assessment has been performed in relation to recreational activities on two artificial freshwater lakes along the river Meuse in The Netherlands. Although the discharges of contaminants into the river Meuse have been reduced in the last decades, which is reflected in decreasing concentrations of pollutants in surface water and suspended matter, the levels in sediments are more persistent. Sediments of the two freshwater lakes appear highly polluted and may pose a health risk in relation to recreational activities. To quantify health risks for carcinogenic (e.g., polycyclic aromatic hydrocarbons) as well as noncarcinogenic compounds (e.g., heavy metals), an exposure assessment model was used. First, we used a standard model that solely uses data on sediment pollution as the input parameter, which is the standard procedure in sediment quality assessments in The Netherlands. The highest intake appeared to be associated with the consumption of contaminated fish and resulted in a health risk for Pb and Zn (hazard index exceeded 1). For the other heavy metals and for benzo(a)pyrene, the total averaged exposure levels were below levels of concern. Secondly, input data for a more location-specific calculation procedure were provided via analyses of samples from sediment, surface water, and suspended matter. When these data (concentrations in surface water) were taken into account, the risk due to consumption of contaminated fish decreased by more than two orders of magnitude and appeared to be negligible. In both exposure assessments, many assumptions were made that contribute to a major degree to the uncertainty of this risk assessment. However, this health risk evaluation is useful as a screening methodology for assessing the urgency of sediment remediation actions.

  11. Effects of dredging operations on sediment quality. Contaminant mobilization in dredged sediments from the Port of Santos, SP, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Torres, Ronaldo J.; Santos, Fernando C.; Mozeto, Antonio A. [Lab. de Biogeoquimica Ambiental, Dept. de Quimica, Univ. Federal de Sao Carlos, Sao Paulo, SP (Brazil); Abessa, Denis M.S.; Maranho, Luciane A.; Davanso, Marcela B. [Campus Experimental do Litoral Paulista, UNESP - Univ. Estadual Paulista ' Julio de Mesquita Filho' , Sao Paulo, SP (Brazil); Nascimento, Marcos R.L. do [Lab. de Pocos de Caldas (LAPOC), CNEN-Comissao Nacional de Energia Nuclear, MG (Brazil)

    2009-10-15

    Background, aim, and scope Contaminated sediments are a worldwide problem, and mobilization of contaminants is one of the most critical issues in environmental risk assessment insofar as dredging projects are concerned. The investigation of how toxic compounds are mobilized during dredging operations in the channel of the Port of Santos, Brazil, was conducted in an attempt to assess changes in the bioavailability and toxicity of these contaminants. Materials and methods Bulk sediment samples and their interstitial waters and elutriates were subjected to chemical evaluation and ecotoxicological assessment. Samples were collected from the channel before dredging, from the dredge's hopper, and from the disposal site and its surroundings. Results The results indicate that the bulk sediments from the dredging site are contaminated moderately with As, Pb, and Zn and severely with Hg, and that polycyclic aromatic hydrocarbon (PAH) concentrations are relatively high. Our results also show a 50% increase in PAH concentrations in suspended solids in the water collected from the hopper dredge. This finding is of great concern, since it refers to the dredge overflow water which is pumped back into the ecosystem. Acute toxicity tests on bulk sediment using the amphipod Tiburonella viscana showed no toxicity, while chronic tests with the sea urchin Lytechinus variegatus showed toxicity in the interstitial waters and elutriates. Results are compared with widely used sediment quality guidelines and with a sediment quality assessment scheme based on various lines of evidence. Conclusions The data presented here indicate that the sediments collected in this port show a certain degree of contamination, especially those from the inner part of the channel. The classification established in this study indicated that sediments from the dredged channel are impacted detrimentally and that sea disposal may disperse contaminants. According to this classification, the sediments are

  12. Potential nitrate removal in a coastal freshwater sediment (Haringvliet Lake, The Netherlands) and response to salinization

    NARCIS (Netherlands)

    Laverman, A.M.; Canavan, R.W.; Slomp, C.P.; Van Cappellen, P.

    2007-01-01

    Nitrogen transformations and their response to salinization were studied in bottom sediment of a coastal freshwater lake (Haringvliet Lake, The Netherlands). The lake was formed as the result of a river impoundment along the south-western coast of the Netherlands, and is currently targeted for

  13. Sediment-hosted contaminants and distribution patterns in the Mississippi and Atchafalaya River Deltas

    Science.gov (United States)

    Flocks, James G.; Kindinger, Jack G.; Ferina, Nicholas; Dreher, Chandra

    2002-01-01

    The Mississippi and Atchafalaya Rivers transport very large amounts of bedload and suspended sediments to the deltaic and coastal environments of the northern Gulf of Mexico. Absorbed onto these sediments are contaminants that may be detrimental to the environment. To adequately assess the impact of these contaminants it is first necessary to develop an understanding of sediment distribution patterns in these deltaic systems. The distribution patterns are defined by deltaic progradational cycles. Once these patterns are identified, the natural and industrial contaminant inventories and their depositional histories can be reconstructed. Delta progradation is a function of sediment discharge, as well as channel and receiving-basin dimensions. Fluvial energy controls the sediment distribution pattern, resulting in a coarse grained or sandy framework, infilled with finer grained material occupying the overbank, interdistributary bays, wetlands and abandoned channels. It has been shown that these fine-grained sediments can carry contaminants through absorption and intern them in the sediment column or redistribute them depending on progradation or degradation of the delta deposit. Sediment distribution patterns in delta complexes can be determined through high-resolution geophysical surveys and groundtruthed with direct sampling. In the Atchafalaya and Mississippi deltas, remote sensing using High-Resolution Single-Channel Seismic Profiling (HRSP) and Sidescan Sonar was correlated to 20-ft vibracores to develop a near-surface geologic framework that identifies variability in recent sediment distribution patterns. The surveys identified bedload sand waves, abandoned-channel back-fill, prodelta and distributary mouth bars within the most recently active portions of the deltas. These depositional features respond to changes in deltaic processes and through their response may intern or transport absorbed contaminants. Characterizing these features provides insight into the

  14. Diffusive Gradients in Thin Films Reveals Differences in Antimony and Arsenic Mobility in a Contaminated Wetland Sediment during an Oxic-Anoxic Transition.

    Science.gov (United States)

    Arsic, Maja; Teasdale, Peter R; Welsh, David T; Johnston, Scott G; Burton, Edward D; Hockmann, Kerstin; Bennett, William W

    2018-02-06

    Antimony (Sb) and arsenic (As) are priority environmental contaminants that often co-occur at mining-impacted sites. Despite their chemical similarities, Sb mobility in waterlogged sediments is poorly understood in comparison to As, particularly across the sediment-water interface (SWI) where changes can occur at the millimeter scale. Combined diffusive gradients in thin films (DGT) and diffusive equilibration in thin films (DET) techniques provided a high resolution, in situ comparison between Sb, As, and iron (Fe) speciation and mobility across the SWI in contaminated freshwater wetland sediment mesocosms under an oxic-anoxic-oxic transition. The shift to anoxic conditions released Fe(II), As(III), and As(V) from the sediment to the water column, consistent with As release being coupled to the reductive dissolution of iron(III) (hydr)oxides. Conversely, Sb(III) and Sb(V) effluxed to the water column under oxic conditions and fluxed into the sediment under anoxic conditions. Porewater DGT-DET depth profiles showed apparent decoupling between Fe(II) and Sb release, as Sb was primarily mobilized across the SWI under oxic conditions. Solid-phase X-ray absorption spectroscopy (XAS) revealed the presence of an Sb(III)-S phase in the sediment that increased in proportion with depth and the transition from oxic to anoxic conditions. The results of this study showed that Sb mobilization was decoupled from the Fe cycle and was, therefore, more likely linked to sulfur and/or organic carbon (e.g., most likely authigenic antimony sulfide formation or Sb(III) complexation by reduced organic sulfur functional groups).

  15. Carbon materials for syngas conditioning and tar removal

    International Nuclear Information System (INIS)

    Romero Millán, Lina María; Sierra Vargas, Fabio Emiro

    2017-01-01

    Within the framework of worldwide energy context, the development of technologies and processes for energy production form renewable and non-conventional sources is a priority. According to this, gasification is an interesting process that converts different kinds of organic materials in fuel gases. The main issue related with this process is the fact that the producer gas contains also contaminants and tars that are undesirable for the gas usage in internal combustion motors or turbines. The present work aims to analyze the actual state of the existing methods to remove tars form gasification fuel gases, emphasizing the use of different kinds of carbon materials. (author)

  16. Abating coal tar seepage into surface water bodies using sheet piles with sealed interlocks

    International Nuclear Information System (INIS)

    Collingwood, B.I.; Boscardin, M.D.; Murdock, R.F.

    1995-01-01

    A former coal tar processing facility processed crude coal tar supplied from manufactured gas plants in the area. Coal-tar-contaminated ground water from the site was observed seeping through an existing timber bulkhead along a tidal river and producing a multicolored sheen on the surface of the river. As part of a short-term measure to abate the seepage into the river, 64-m long anchored sheet pile wall with sheet pile wing walls at each end was constructed inland of the of the timber bulkhead. The sheet piles extended to low-permeability soils at depth and the interlocks of the sheet piles were provided with polyurethane rubber seals. Based on postconstruction observations for leakage and sheens related to leakage, the steel sheet piles with polyurethane rubber interlock seals appeared to provide a successful seal and abate coal-tar-contaminated ground water seepage into the river. The tie rod penetration sealing proved to be a more problematic detail, but through several postconstruction grouting episodes, an effective seal was produced

  17. Induction of mouthpart deformities in chironomid larvae exposed to contaminated sediments

    Energy Technology Data Exchange (ETDEWEB)

    Di Veroli, Alessandra [Dipartimento di Biologia Cellulare e Ambientale, Universita degli Studi di Perugia, Via Elce Di Sotto, 06123 Perugia (Italy); Goretti, Enzo [Dipartimento di Biologia Cellulare e Ambientale, Universita degli Studi di Perugia, Via Elce Di Sotto, 06123 Perugia (Italy); Paumen, Miriam Leon; Kraak, Michiel H.S.; Admiraal, Wim [Department of Aquatic Ecology and Ecotoxicology, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Sciencepark 904, 1098 XH Amsterdam (Netherlands)

    2012-07-15

    The aim of the present study was to improve the cause-effect relationship between toxicant exposure and chironomid mouthpart deformities, by linking induction of mouthpart deformities to contaminated field sediments, metal mixtures and a mutagenic polycyclic aromatic compound metabolite (acridone). Mouthpart deformities in Chironomus riparius larvae were induced by both the heavy metal mixture and by acridone. A clear correlation between metal concentrations in the sediment and deformities incidence was only observed when the contaminated field sediments were left out of the analysis, probably because these natural sediments contained other toxic compounds, which could be responsible for a higher incidence of deformities than predicted by the measured metal concentrations only. The present study clearly improved the cause-effect relationship between toxicant exposure and the induction of mouthpart deformities. It is concluded that the incidence of mouthpart deformities may better reflect the potential toxicity of contaminated sediments than chemical analysis. - Highlights: Black-Right-Pointing-Pointer We tested the induction of deformities in C. riparius in laboratory toxicity experiments. Black-Right-Pointing-Pointer We used field sediments and spiked sediments with heavy metals and mutagenic PAC. Black-Right-Pointing-Pointer Mouthpart deformities were induced both by heavy metal mixtures and by acridone. Black-Right-Pointing-Pointer A correlation between metal concentrations in the sediment and deformities was found. Black-Right-Pointing-Pointer Mouthpart deformities better reflect the toxicity of sediments than chemical analysis. - Mouthpart deformities of Chironomus riparius larvae better reflect the toxicity of sediments than chemical analysis.

  18. Toxicity and biodegradation of PCBs in contaminated sediments

    International Nuclear Information System (INIS)

    Dercova, K.; Cicmanova, J.; Lovecka, P.; Demnerova, K.; Mackova, M.; Hucko, P.; Kusnir, P.

    2006-01-01

    PCBs represent a serious ecological problem due to their low degradability, high toxicity, and strong bioaccumulation. Because of many environmental and economical problems, there are efforts to develop bio-remediation technologies for decontamination of the PCB-polluted areas. PCB were used by storage of spent nuclear fuel in nuclear power plants Jaslovske Bohunice. In the locality of the former producer of PCB - Chemko Strazske a. s. - big amount of these substances is still persisting in sediments and soil. The goal of this study was to analyze the contaminated sediments from Strazsky canal and Zemplinska Sirava water reservoir from several points of view. The study of eco-toxicity confirmed that both sediments were toxic for various tested organisms. The genotoxicity test has not proved the mutagenic effect. The subsequent step included microbiological analysis of the contaminated sediments and isolation of pure bacterial cultures capable of degrading PCBs. In order to determine the genetic potential for their biodegradability, the gene bphA1 was identified using PCR technique in their genomes. This gene codes the enzyme biphenyl-dioxygenase, which is responsible for PCB degradation. The final goal was to perform aerobic biodegradation of PCBs in the sediments. The bacteria present in both sediments are able to degrade certain low chlorinated congeners. The issue of biodiversity is still open and has to be studied to reveal the real cooperation between bacteria. (authors)

  19. Review on utilization of biochar for metal-contaminated soil and sediment remediation.

    Science.gov (United States)

    Wang, Mingming; Zhu, Yi; Cheng, Lirong; Andserson, Bruce; Zhao, Xiaohui; Wang, Dayang; Ding, Aizhong

    2018-01-01

    Biochar is a carbon-neutral or even carbon-negative material produced through thermal decomposition of plant- and animal-based biomass under oxygen-limited conditions. Recently, there has been an increasing interest in the application of biochar as an adsorbent, soil ameliorant and climate mitigation approach in many types of applications. Metal-contaminated soil remediation using biochar has been intensively investigated in small-scale and pilot-scale trials with obtained beneficial results and multifaceted effects. But so far, the study and application of biochar in contaminated sediment management has been very limited, and this is also a worldwide problem. Nonetheless, there is reason to believe that the same multiple benefits can also be realized with these sediments due to similar mechanisms for stabilizing contaminants. This paper provides a review on current biochar properties and its use as a sorbent/amendment for metal-contaminated soil/sediment remediation and its effect on plant growth, fauna habits as well as microorganism communities. In addition, the use of biochar as a potential strategy for contaminated sediment management is also discussed, especially as regards in-situ planning. Finally, we highlight the possibility of biochar application as an effective amendment and propose further research directions to ensure the safe and sustainable use of biochar as an amendment for remediation of contaminated soil and sediment. Copyright © 2017. Published by Elsevier B.V.

  20. Algal-bacterial interactions in metal contaminated floodplain sediments

    International Nuclear Information System (INIS)

    Boivin, M.E.Y.; Greve, G.D.; Garcia-Meza, J.V.; Massieux, B.; Sprenger, W.; Kraak, M.H.S.; Breure, A.M.; Rutgers, M.; Admiraal, W.

    2007-01-01

    The aim of the present study was to investigate algal-bacterial interactions in a gradient of metal contaminated natural sediments. By means of multivariate techniques, we related the genetic structure (denaturing gradient gel electrophoresis, DGGE) and the physiological structure (community-level physiological profiling, CLPP) of the bacterial communities to the species composition of the algal communities and to the abiotic environmental variables, including metal contamination. The results revealed that genetic and physiological structure of the bacterial communities correlated with the species composition of the algal community, but hardly to the level of metal pollution. This must be interpreted as an indication for a strong and species-specific linkage of algal and bacterial species in floodplain sediments. Metals were, however, not proven to affect either the algal or the bacterial communities of the Dutch river floodplains. - Algal and bacterial communities in floodplain sediments are interlinked, but are not affected by metal pollution

  1. In situ electro-osmotic cleanup of tar contaminated soil—Removal of polycyclic aromatic hydrocarbons

    KAUST Repository

    Lima, Ana T.

    2012-12-01

    An in situ electro-osmosis experiment was set up in a tar contaminated clay soil in Olst, the Netherlands, at the site of a former asphalt factory. The main goal of this experiment was to remove polycyclic aromatic hydrocarbons (PAHs) from the contaminated clay layer by applying an electric gradient of 12 V m-1 across the soil over an electrode distance of 1 m. With the movement of water by electro-osmosis and the addition of a non-ionic surfactant (Tween 80), the non-polar PAHs were dragged along by convection and removed from the fine soil fraction. Soil samples were taken at the start and after 159 days at the end of the experiment. Water at the electrode wells was sampled regularly during the course of the experiment. The results reflect the heterogeneity of the soil characteristics and show the PAH concentrations within the experimental set up. After first having been released into the anolyte solution due to extraction by Tween 80 and subsequent diffusion, PAH concentrations increased significantly in the electrode reservoirs at the cathode side after 90 days of experiment. Although more detailed statistical analysis is necessary to quantify the efficiency of the remediation, it can be concluded that the use of electro-osmosis together with a non-ionic surfactant is a feasible technique to mobilize non-polar organic contaminants in clayey soils. Crown Copyright © 2011 Published by Elsevier Ltd. All rights reserved.

  2. Contaminated sediment research task: SHC Task 3.61.3

    Science.gov (United States)

    A poster presentation for the SHC BOSC review will summarize the research efforts under Sustainable and Healthy Communities Research Program (SHC) in the Contaminated Sediment Task within the Contaminated Sites Project. For the Task, Problem Summary & Decision Context; Task O...

  3. Decomposition of tar in gas from updraft gasifier by thermal cracking

    DEFF Research Database (Denmark)

    Brandt, Peder; Henriksen, Ulrik Birk

    2000-01-01

    Continuing earlier work with tar reduction by partial oxidation of pyrolysis gas [1] thermal cracking has been evaluated as a gas cleaning process. The work has been focusing on cleaning gas from updraft gasifiers, and the long term purpose is to develop a tar cleaning unit based on thermal...... cracking. An experimental set-up has been built, in which a flow of contaminated gas can be heated up to 1290°C in a reactor made of pure Al2O3. Four measurements were made. Three with gas from a pyrolysis unit simulating updraft gasifier, and one with gas from an updraft gasifier. Cracking temperatures...... was 1200, 1250 and 1290°C, and the residence time at this temperature was 0.5 second. The measurements show that at the selected residence time of 0.5 second, the gas flow in a thermal tar cracking unit has to be heated to at least 1250°C to achieve sufficient tar cleaning. At 1290°C, a tar content as low...

  4. Kinetics of hydrophobic organic contaminant extraction from sediment by granular activated carbon

    NARCIS (Netherlands)

    Rakowska, M.I.; Kupryianchyk, D.; Smit, M.; Koelmans, A.A.; Meent, van de D.

    2014-01-01

    Ex situ solid phase extraction with granular activated carbon (GAC) is a promising technique to remediate contaminated sediments. The methods' efficiency depends on the rate by which contaminants are transferred from the sediment to the surface of GAC. Here, we derive kinetic parameters for

  5. Management and the conservation of freshwater ecosystems

    Science.gov (United States)

    Wipfli, Mark S.; Richardson, John S.

    2015-01-01

    Riparian areas are the terrestrial environment adjacent to water that both influences and is influenced by the aquatic feature (Gregory et al., 1991; Naiman et al., 2010). Riparian areas along streams provide shade, sources of wood and organic matter, contribute to bank stability, filter sediments, take up excess nutrients from groundwater inputs, and other key processes that protect freshwaters (e.g. Naiman et al., 2010; Richardson & Danehy, 2007; Figure 9.1). Riparian areas also increase biodiversity through habitat complexity and close juxtaposition of aquatic and terrestrial environments (Quinn et al., 2004; Naiman et al., 2010). Alterations to riparian areas, despite their small area relative to the landscape, have disproportionate effects on habitats and fish communities (Naiman et al., 2010; Wipfli & Baxter, 2010). Key habitat losses and alterations are derived from modification of riparian areas by reducing instream habitat complexity (Bilby & Ward, 1989; Fausch & Northcote, 1992; Naiman et al., 2010), diminishing the productive basis of freshwater food webs (Belsky et al., 1999; Quinn et al., 2004), increasing nutrient, contaminant and sediment intrusion (Muscutt et al., 1993; Daniels & Gilliam, 1996; Nguyen et al., 1998; Waters, 1999).

  6. Stability of plutonium contaminated sediments in the Miami--Erie Canal

    International Nuclear Information System (INIS)

    Farmer, B.M.; Carfagno, D.G.

    1978-01-01

    This study was conducted to evaluate the stability of plutonium-contaminated sediment in the Miami-Erie Canal. Correlations were sought to relate concentrations at air sampling stations to plutonium-238 concentrations in air and stack emissions, wind direction, particulate loading, rainfall, and construction activities. There appears to be some impact on airborne concentrations at air sampling stations 122 and 123 from the contaminated sediment in the canal and ponds area. For purposes of this evaluation, it was assumed that the plutonium-238 found in the air samples came from the contaminated sediment in the canal/ponds area. To complete the evaluation of the inhalation pathway, dose calculations were performed using actual airborne concentrations of plutonium-238 measured at sampler 123. The dose equivalent to an individual in that area was calculated for 1 yr and 70 yr. Dose calculations were also performed on potential uptake of contaminated vegetation from that area for 1 yr and 70 yr. This study indicates that, although the contaminated sediments in the canal and pond area appear to contribute to airborne plutonium-238, the observed maximum monthly concentration of plutonium-238 in air is a small fraction of the DOE Radioactivity Concentration Guide (RCG) and the nine-month average concentration of plutonium-238 in air observed thus far during 1977 is less than 1% of the RCG. Dose equivalents, conservatively calculated from these actual data, are well within existing DOE standards and proposed EPA guidance

  7. Effects of sediment quality on macroinvertebrates in the Sunraysia region of the Murray-Darling Rivers, Australia

    Energy Technology Data Exchange (ETDEWEB)

    Sharley, David J. [Centre for Environmental Stress and Adaptation Research-Hoffmann Laboratory, Zoology Department, University of Melbourne, Level 2, Bio 21 Institute, 30 Flemington Road, Parkville, Victoria 3010 (Australia)], E-mail: sharleyd@unimelb.edu.au; Hoffmann, Ary A. [Centre for Environmental Stress and Adaptation Research-Hoffmann Laboratory, Zoology Department, University of Melbourne, Level 2, Bio 21 Institute, 30 Flemington Road, Parkville, Victoria 3010 (Australia); Pettigrove, Vincent [Research and Technology, Melbourne Water, PO Box 4342, Melbourne, Victoria 3001 (Australia)

    2008-12-15

    A field-based microcosm approach was tested to identify deterioration of sediment quality in waterways using freshwater macroinvertebrates. The method can potentially identify the nature of contaminants based on species-specific responses. Sediments were collected from the Murray and Darling Rivers and irrigation drains within the Sunraysia region of south-eastern Australia and compared to non-polluted reference sediment. Clean sediments were also spiked with fertiliser to test whether nutrients affected the aquatic fauna. Seven of the eight sediments from the Sunraysia region had a negative impact on the macroinvertebrates, in particular sediment from the Darling River, which supported an impoverished fauna. Three species of chironomid showed varied responses to sediment quality and, although it was hypothesised that nutrients may have impacted on the macroinvertebrate fauna, the results suggest that other pollutants are also involved. The field-based microcosm method proved effective for determining the impact of sediment quality on indigenous macroinvertebrates. - Sediment quality effects on freshwater macroinvertebrates are isolated.

  8. Effects of sediment quality on macroinvertebrates in the Sunraysia region of the Murray-Darling Rivers, Australia

    International Nuclear Information System (INIS)

    Sharley, David J.; Hoffmann, Ary A.; Pettigrove, Vincent

    2008-01-01

    A field-based microcosm approach was tested to identify deterioration of sediment quality in waterways using freshwater macroinvertebrates. The method can potentially identify the nature of contaminants based on species-specific responses. Sediments were collected from the Murray and Darling Rivers and irrigation drains within the Sunraysia region of south-eastern Australia and compared to non-polluted reference sediment. Clean sediments were also spiked with fertiliser to test whether nutrients affected the aquatic fauna. Seven of the eight sediments from the Sunraysia region had a negative impact on the macroinvertebrates, in particular sediment from the Darling River, which supported an impoverished fauna. Three species of chironomid showed varied responses to sediment quality and, although it was hypothesised that nutrients may have impacted on the macroinvertebrate fauna, the results suggest that other pollutants are also involved. The field-based microcosm method proved effective for determining the impact of sediment quality on indigenous macroinvertebrates. - Sediment quality effects on freshwater macroinvertebrates are isolated

  9. Characterization of heavy-metal-contaminated sediment by using unsupervised multivariate techniques and health risk assessment.

    Science.gov (United States)

    Wang, Yeuh-Bin; Liu, Chen-Wuing; Wang, Sheng-Wei

    2015-03-01

    This study characterized the sediment quality of the severely contaminated Erjen River in Taiwan by using multivariate analysis methods-including factor analysis (FA), self-organizing maps (SOMs), and positive matrix factorization (PMF)-and health risk assessment. The SOMs classified the dataset with similar heavy-metal-contaminated sediment into five groups. FA extracted three major factors-traditional electroplating and metal-surface processing factor, nontraditional heavy-metal-industry factor, and natural geological factor-which accounted for 80.8% of the variance. The SOMs and FA revealed the heavy-metal-contaminated-sediment hotspots in the middle and upper reaches of the major tributary in the dry season. The hazardous index value for health risk via ingestion was 0.302. PMF further qualified the source apportionment, indicating that traditional electroplating and metal-surface-processing industries comprised 47% of the health risk posed by heavy-metal-contaminated sediment. Contaminants discharged from traditional electroplating and metal-surface-processing industries in the middle and upper reaches of the major tributary must be eliminated first to improve the sediment quality in Erjen River. The proposed assessment framework for heavy-metal-contaminated sediment can be applied to contaminated-sediment river sites in other regions. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Effect of Lake Trophic Status and Rooted Macrophytes on Community Composition and Abundance of Ammonia-oxidizing Prokaryotes in Freshwater Sediments

    DEFF Research Database (Denmark)

    Herrmann, Martina; Saunders, Aaron Marc; Schramm, Andreas

    2009-01-01

    ) and slightly higher for AOA in unvegetated sediment and AOA in association with M. alterniflorum (0.01 to 2%), while AOA accounted for up to 5% in the rhizospheres of L. uniflora and J. bulbosus. These results indicate that (i) AOA are at least as numerous as AOB in freshwater sediments, (ii) aquatic...

  11. Relating groundwater and sediment chemistry to microbial characterization at a BTEX-contaminated site

    International Nuclear Information System (INIS)

    Pfiffner, S.M.; Palumbo, A.V.; McCarthy, J.F.; Gibson, T.

    1996-01-01

    The National Center for Manufacturing Science is investigating bioremediation of petroleum hydrocarbon at a site in Belleville, Michigan. As part of this study we examined the microbial communities to help elucidate biodegradative processes currently active at the site. We observed high densities of aerobic hydrocarbon degraders and denitrifiers in the less-contaminated sediments. Low densities of iron and sulfate reducers were measured in the same sediments. In contrast, the highly-contaminated sediments showed low densities of aerobic hydrocarbon degraders and denitrifiers and high densities of iron and sulfate reducers. Methanogens were also found in these highly-contaminated sediments. These contaminated sediments also showed a higher biomass, by phospholipid fatty acids, and greater ratios of phospholipid fatty acids which indicate stress within the microbial community. Aquifer chemistry analyses indicated that the more-contaminated area was more reduced and had lower sulfate than the less-contaminated area. These conditions suggest that the subsurface environment at the highly-contaminated area had progressed into sulfate reduction and methanogensis. The less-contaminated area, although less reduced, also appeared to be progressing into primarily iron- and sulfate-reducing microbial communities. The proposed treatment to stimulate bioremediation includes addition of oxygen and nitrate. Groundwater chemistry and microbial analyses revealed significant differences resulted from the injection of dissolved oxygen and nitrate in the subsurface. These differences included increases in pH and Eh and large decreases in BTEX, dissolved iron, and sulfate concentrations at the injection well

  12. Study of the sediment contamination levels in a mangrove swamp polluted by a marine oil spill

    Energy Technology Data Exchange (ETDEWEB)

    Wong, T.W.Y.; Ke, L.; Wong, Y.S.; Tam, N.F.Y. [City University of Hong Kong, Hong Kong SAR (China)

    2002-07-01

    The pattern of oil retention in mangrove sediments was studied in an effort to determine the temporal changes of petroleum hydrocarbon concentrations and composition several months after oil spills occur. Mangroves are inter-tidal wetlands in tropical and subtropical coastlines. Due to the anoxic and water logging characteristics of mangrove sediments, oil residues linger much longer in these wetlands compared to other coastal habitats. In November 2000, an accidental oil spill occurred in the Pearl River Estuary in which approximately 230,000 litres of crude oil was leaked from an oil tanker. The spilled oil migrated to the YiO, a typical mangrove swamp in Hong Kong Special Administrative Region. The degree of oil contamination in the sediments depended on the sediment texture and topography of the mangrove. The total petroleum hydrocarbon (TPH) concentration of the sediments in the most affected area near a freshwater creek flowing into the sea was 130 times higher than normal, one month after the accident. The mean TPH concentration was 2862 ug/g of dry sediment while the mean carbon preference index was 1.22 compared to the background value of 3.97. The temporal changes of the petroleum hydrocarbon level in 5 defined areas were examined for 7 months after the spill. The most polluted area next to the creek was determined to have very high TPH levels in the muddy sediments even 7 months after the spill. Oil residues infiltrated as deep as 20 cm into the sediments, making it more difficult to degrade than surface pollution and posing long-term adverse effects on trees in the area. It was determined that with growing industrialization and increasing demands for fuel and energy supply, mangroves in South China should be ranked as top priority for protection from oil spills. 19 refs., 6 tabs., 6 figs.

  13. Study of the sediment contamination levels in a mangrove swamp polluted by a marine oil spill

    International Nuclear Information System (INIS)

    Wong, T.W.Y.; Ke, L.; Wong, Y.S.; Tam, N.F.Y.

    2002-01-01

    The pattern of oil retention in mangrove sediments was studied in an effort to determine the temporal changes of petroleum hydrocarbon concentrations and composition several months after oil spills occur. Mangroves are inter-tidal wetlands in tropical and subtropical coastlines. Due to the anoxic and water logging characteristics of mangrove sediments, oil residues linger much longer in these wetlands compared to other coastal habitats. In November 2000, an accidental oil spill occurred in the Pearl River Estuary in which approximately 230,000 litres of crude oil was leaked from an oil tanker. The spilled oil migrated to the YiO, a typical mangrove swamp in Hong Kong Special Administrative Region. The degree of oil contamination in the sediments depended on the sediment texture and topography of the mangrove. The total petroleum hydrocarbon (TPH) concentration of the sediments in the most affected area near a freshwater creek flowing into the sea was 130 times higher than normal, one month after the accident. The mean TPH concentration was 2862 ug/g of dry sediment while the mean carbon preference index was 1.22 compared to the background value of 3.97. The temporal changes of the petroleum hydrocarbon level in 5 defined areas were examined for 7 months after the spill. The most polluted area next to the creek was determined to have very high TPH levels in the muddy sediments even 7 months after the spill. Oil residues infiltrated as deep as 20 cm into the sediments, making it more difficult to degrade than surface pollution and posing long-term adverse effects on trees in the area. It was determined that with growing industrialization and increasing demands for fuel and energy supply, mangroves in South China should be ranked as top priority for protection from oil spills. 19 refs., 6 tabs., 6 figs

  14. Evidence for mild sediment Pb contamination affecting leaf-litter decomposition in a lake.

    Science.gov (United States)

    Oguma, Andrew Y; Klerks, Paul L

    2015-08-01

    Much work has focused on the effects of metal-contaminated sediment on benthic community structure, but effects on ecosystem functions have received far less attention. Decomposition has been widely used as an integrating metric of ecosystem function in lotic systems, but not for lentic ones. We assessed the relationship between low-level sediment lead (Pb) contamination and leaf-litter decomposition in a lentic system. We measured 30-day weight loss in 30 litter-bags that were deployed along a Pb-contamination gradient in a cypress-forested lake. At each deployment site we also quantified macrobenthos abundance, dissolved oxygen, water depth, sediment organic content, sediment silt/clay content, and both total sediment and porewater concentrations of Cd, Cu, Ni, Pb and Zn. Principal components (PC) analysis revealed a negative relationship between Pb concentration and benthic macroinvertebrate abundance, and this covariation dominated the first PC axis (PC1). Subsequent correlation analyses revealed a negative relationship between PC1 and percent leaf-litter loss. Our results indicate that leaf-litter decomposition was related to sediment Pb and benthic macroinvertebrate abundance. They also showed that ecosystem function may be affected even where sediment Pb concentrations are mostly below threshold-effects sediment quality guidelines--a finding with potential implications for sediment risk assessment. Additionally, the litter-bag technique used in this study showed promise as a tool in risk assessments of metal-contaminated sediments in lentic systems.

  15. In-situ and laboratory study of radiocaesium mobility in freshwater sediments

    International Nuclear Information System (INIS)

    Comans, R.N.J.; Bonouvrie, P.A.; Lange, G.J. de

    1992-09-01

    The title project was designed to identify areas of our understanding of the transport of radionuclides through aquatic environments and uptake by fish which limit the general applicability of the present generation of mathematical models. The initial programme concentrated on four areas: 1. Chemical processes underlying adsorption onto particles; 2. The processes involved in the enhanced transport of radio- caesium from some catchments; 3. Processes of remobilization in sediments and at the seawater/freshwater interface; 4. Effects of water chemistry and the ecology of aquatic organisms on the uptake, storage and excretion of radio- nuclides. (author). 6 refs., 5 figs

  16. MEASURING CONTAMINANT RESUSPENSION RESULTING FROM SEDIMENT CAPPING

    Science.gov (United States)

    This Sediment Issue summarizes two studies undertaken at marine sites by the National Risk Management Research Laboratory of U.S. EPA to evaluate the resuspension of surface materials contaminated with polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) b...

  17. Three decades of TBT contamination in sediments around a large scale shipyard.

    Science.gov (United States)

    Kim, Nam Sook; Shim, Won Joon; Yim, Un Hyuk; Ha, Sung Yong; An, Joon Geon; Shin, Kyung Hoon

    2011-08-30

    Tributyltin (TBT) contamination in sediments was investigated in the vicinity of a large-scale shipyard in the years after the implementation of a total ban on the use of TBT based antifouling paints in Korea. Extremely high level of TBT (36,292ng Sn/g) in surface sediment was found at a station in front of a drydock and near surface runoff outfall of the shipyard. TBT concentration in surface sediments of Gohyeon Bay, where the shipyard is located, showed an apparent decreased TBT concentration gradient from the shipyard towards the outer bay. The vertical distribution of TBT contamination derived from a sediment core analysis demonstrated a significant positive correlation (r(2)=0.88; pTBT concentrations at six stations surveyed before (2003) and seven years after (2010) the total ban showed no significant differences (p>0.05). Despite the ban on the use of TBT, including ocean going vessels, surface sediments are still being heavily contaminated with TBT, and its levels well exceeded the sediment quality guideline or screening values. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Use of advanced chemical fingerprinting in PAH source identification and allocation at a coal tar processing site

    International Nuclear Information System (INIS)

    Brown, J.S.; Boehm, P.D.; Douglas, G.S.

    1995-01-01

    Advanced chemical fingerprinting analyses were used to determine source allocation at a former coal tar processing facility which had been converted to a petroleum recycling site. Soil samples from the site had high petroleum hydrocarbon concentrations and elevated levels of polynuclear aromatic hydrocarbons (PAH). Comparisons of PAH distributions were used to differentiate the coal tar hydrocarbons from the petroleum hydrocarbons in soil samples. A more specific technique was needed to accurately allocate the contribution of the two sources to the observed PAH contamination in the soil. Petroleum biomarkers (steranes and triterpanes) which are present in crude oils and many refined petroleum products but are absent in coal tar were used to quantitatively allocate the source of the PAH contamination based on the relative ratio of the PAH to the biomarkers in soil samples. Using the resulting coal tar/petroleum source ratio the contribution of petroleum to the overall PAH contamination at the site was calculated. A multivariate statistical technique (principal component analysis or PCA) was used to provide an independent validation of the source allocation. The results of the source allocation provided a foundation for the site clean-up and remediation costs

  19. Potential Ecological Effects of Contaminants in the Exposed Par Pond Sediments

    International Nuclear Information System (INIS)

    Paller, M.H.; Wike, L.D.

    1996-08-01

    Sediment and small mammal samples were collected from the exposed sediments of Par Pond in early 1995, shortly before the reservoir was refilled after a 4-year drawdown. Sampling was confined to elevations between 58 and 61 meters (190 and 200 feet) above mean sea level, which includes the sediments likely to be exposed if the Par Pond water level is permitted to fluctuate naturally. Both soil and small mammal samples were analyzed for a number of radionuclides and metals. Some of the soil samples were also analyzed for organic contaminants. The objective of the study was to determine if contaminant levels in the Par Pond sediments were high enough to cause deleterious ecological effects

  20. The impact of storms and stratification on sediment transport in the Rhine region of freshwater influence

    NARCIS (Netherlands)

    Flores, Raúl P.; Rijnsburger, S.; Horner-Devine, Alexander R.; Souza, Alejandro J.; Pietrzak, J.D.

    2017-01-01

    We present measurements of along and across-shore sediment transport in a region of the Dutch coast 10 km north of the Rhine River mouth. This section of the coast is characterized by strong vertical density stratification because it is within the midfield region of the Rhine region of freshwater

  1. Seasonal and spatial variations in heterotrophic nanoflagellate and bacteria abundances in sediments of a freshwater littoral zone

    NARCIS (Netherlands)

    Starink, Mathieu; Bär-Gilissen, M.J.; Cappenberg, T.E.

    1996-01-01

    We studied seasonal variation in heterotrophic nanoflagellates (HNAN) and bacterial, densities at different depths in the sediment of two freshwater littoral stations. Station 1 was in a reed bed of Phragmites australis; station 2 was outside the reed zone in open water. Benthic HNAN abundances

  2. Green remediation and recycling of contaminated sediment by waste-incorporated stabilization/solidification.

    Science.gov (United States)

    Wang, Lei; Tsang, Daniel C W; Poon, Chi-Sun

    2015-03-01

    Navigational/environmental dredging of contaminated sediment conventionally requires contained marine disposal and continuous monitoring. This study proposed a green remediation approach to treat and recycle the contaminated sediment by means of stabilization/solidification enhanced by the addition of selected solid wastes. With an increasing amount of contaminated sediment (20-70%), the 28-d compressive strength of sediment blocks decreased from greater than 10MPa to slightly above 1MPa. For augmenting the cement hydration, coal fly ash was more effective than lime and ground seashells, especially at low sediment content. The microscopic and spectroscopic analyses showed varying amounts of hydration products (primarily calcium hydroxide and calcium silicate hydrate) in the presence of coal fly ash, signifying the influence of pozzolanic reaction. To facilitate the waste utilization, cullet from beverage glass bottles and bottom ashes from coal combustion and waste incineration were found suitable to substitute coarse aggregate at 33% replacement ratio, beyond which the compressive strength decreased accordingly. The mercury intrusion porosimetry analysis indicated that the increase in the total pore area and average pore diameter were linearly correlated with the decrease of compressive strength due to waste replacement. All the sediment blocks complied with the acceptance criteria for reuse in terms of metal leachability. These results suggest that, with an appropriate mixture design, contaminated sediment and waste materials are useful resources for producing non-load-bearing masonry units or fill materials for construction uses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Comparison of contaminants from different trophic levels and ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, R.; Riget, F. [Department of Arctic Environment, Ministry of Environment and Energy, National Environmental Research Institute, Tagensvej 135, 4 floor, DK-2200 Copenhagen (Denmark); Cleemann, M. [Department of Environmental Chemistry, Ministry of Environment and Energy, National Environmental Research Institute, Frederiksborgvej 399, DK-4000 Roskilde (Denmark); Aarkrog, A. [Risoe National Laboratory, Frederiksborgvej 399, DK-4000 Roskilde (Denmark); Johansen, P. [Department of Arctic Environment, Ministry of Environment and Energy, National Environmental Research Institute, Tagensvej 135, 4 floor, DK-2200 Copenhagen (Denmark); Hansen, J.C. [Risoe National Laboratory, Frederiksborgvej 399, DK-4000 Roskilde (Denmark)

    2000-01-17

    The present paper provides an overview of the priority contaminants and media from the Greenland part of the Arctic Monitoring and Assessment Program. Levels and accumulation patterns of heavy metals, POPs and a radionuclide (137Cs) are compared from the terrestrial, freshwater and marine ecosystems. Of the nine compounds presented, seven (Cd, Hg, Se, {sigma}PCB, {sigma}DDT, {sigma}HCH, HCB) increased in concentration towards higher trophic levels. For these contaminants the concentrations in soil and aquatic sediment were in the same order of magnitude, whereas the concentrations in marine biota were higher than found in the freshwater and terrestrial ecosystems probably due to the presence of longer food chains. Pb and 137Cs showed the reverse pattern compared with the other compounds. The concentrations in soil and aquatic sediments decreased in the order terrestrial, freshwater and marine ecosystems, which was reflected in the biota as well. Reindeer had similar or lower levels of Pb and 137Cs than lichens. Levels of Pb and 137Cs in marine biota did not show the same clear increase towards higher trophic as found for the other analysed compounds. Greenland Inuit contains considerably less mercury but higher levels of {sigma}PCB, {sigma}DDT and HCB than other Arctic marine top consumers.

  4. Contaminated Sediment Management in Dam Removals and River Restoration Efforts: Critical Need for Research and Policy Development

    Science.gov (United States)

    Evans, J. E.

    2015-12-01

    Over 1,000 U.S. dams have been removed (1975-2015) for reasons including obsolescence, liability concerns, water quality upgrades, fisheries, or ecosystem enhancements. Contaminated sediment can significantly complicate the approval process, cost, and timeline of a dam removal, or stop it entirely. In a dam removal, reservoir sediment changes from a sink to a source of contaminants. Recently, the Sierra Club sued to stop the removal of a large dam in Ohio because of the potential impact of phosphate releases on toxic algal blooms in Lake Erie. Heavy metals, PCBs, PAHs, pesticides, and petroleum hydrocarbons can be present in reservoir sediments. In a non-dam removal scenario, reservoir management tools range from "no action" to dredging, dewatering and removal, or sediment capping. But it is not clear how these reservoir management techniques apply to dam removals. Case studies show typically >80% of the reservoir sediment is eventually eroded, precluding sediment capping as a containment option. However, the released contaminants are diluted by mixing with "clean" sediment and are transported to different physio-chemical environments which may immobilize or biodegrade the contaminants. Poorly understood options include phased drawdown/reseeding the former reservoir to contain sediments, diking contaminant "hot spots," and addressing contaminant stratigraphy (where historical use created "hot layers" in the reservoir sediment). Research and policy development needs include: (1) assessment methods based on synergistic effects of multiple contaminants being present; (2) ways to translate the pre-removal contaminant concentrations to post-removal health risks downstream; (3) evaluation of management practices for contaminant "hot spots" and "hot layers;" (4) tools to forecast the presence of contaminated sediment using easily accessible information; and (5) ways to limit liability risk for organizations participating in dam removals involving contaminated sediment.

  5. Sediment processes and mercury transport in a frozen freshwater fluvial lake (Lake St. Louis, QC, Canada).

    Science.gov (United States)

    Canário, João; Poissant, Laurier; O'Driscoll, Nelson; Vale, Carlos; Pilote, Martin; Lean, David

    2009-04-01

    An open-bottom and a closed-bottom mesocosm were developed to investigate the release of mercury from sediments to the water column in a frozen freshwater lake. The mesoscosms were deployed in a hole in the ice and particulate mercury (Hg(P)) and total dissolved mercury (TDHg) were measured in sediments and in water column vertical profiles. In addition, dissolved gaseous mercury (DGM) in water and mercury water/airflux were quantified. Concentrations of TDHg, DGM, and mercury flux were all higher in the open-bottom mesocosm than in the closed-bottom mesocosm. In this paper we focus on the molecular diffusion of mercury from the sediment in comparison with the TDHg accumulation in the water column. We conclude that the molecular diffusion and sediment resuspension play a minor role in mercury release from sediments suggesting that solute release during ebullition is an important transport process for mercury in the lake.

  6. The remediation of heavy metals contaminated sediment.

    Science.gov (United States)

    Peng, Jian-Feng; Song, Yong-Hui; Yuan, Peng; Cui, Xiao-Yu; Qiu, Guang-Lei

    2009-01-30

    Heavy metal contamination has become a worldwide problem through disturbing the normal functions of rivers and lakes. Sediment, as the largest storage and resources of heavy metal, plays a rather important role in metal transformations. This paper provides a review on the geochemical forms, affecting factors and remediation technologies of heavy metal in sediment. The in situ remediation of sediment aims at increasing the stabilization of some metals such as the mobile and the exchangeable fractions; whereas, the ex situ remediation mainly aims at removing those potentially mobile metals, such as the Mn-oxides and the organic matter (OM) fraction. The pH and OM can directly change metals distribution in sediment; however oxidation-reduction potential (ORP), mainly through changing the pH values, indirectly alters metals distribution. Mainly ascribed to their simple operation mode, low costs and fast remediation effects, in situ remediation technologies, especially being fit for slight pollution sediment, are applied widely. However, for avoiding metal secondary pollution from sediment release, ex situ remediation should be the hot point in future research.

  7. VARIATIONS IN THE SPECTRAL PROPERTIES OF FRESHWATER AND ESTUARINE CDOM CAUSED BY PARTITIONING ONTO RIVER AND ESTUARINE SEDIMENTS

    Science.gov (United States)

    The optical properties and geochemical cycling of chromophoric dissolved organic matter (CDOM) are altered by its sorption to freshwater and estuarine sediments. Measured partition coefficients (Kp) of Satilla River (Georgia) and Cape Fear River estuary (North Carolina) CDOM ran...

  8. Investigations of contaminated fluvial sediment deposits: merging of statistical and geomorphic approaches.

    Science.gov (United States)

    Ryti, Randall T; Reneau, Steven L; Katzman, Danny

    2005-05-01

    Concentrations of contaminants in sediment deposits can have large spatial variability resulting from geomorphic processes acting over long time periods. Thus, systematic (e.g., regularly spaced sample locations) or random sampling approaches might be inefficient and/or lead to highly biased results. We demonstrate the bias associated with systematic sampling and compare these results to those achieved by methods that merge a geomorphic approach to evaluating the physical system and stratified random sampling concepts. By combining these approaches, we achieve a more efficient and less biased characterization of sediment contamination in fluvial systems. These methods are applied using a phased sampling approach to characterize radiological contamination in sediment deposits in two semiarid canyons that have received historical releases from the Los Alamos National Laboratory. Uncertainty in contaminant inventory was used as a metric to evaluate the adequacy of sampling during these phased investigations. Simple, one-dimensional Monte Carlo simulations were used to estimate uncertainty in contaminant inventory. We also show how one can use stratified random sampling theory to help estimate uncertainty in mean contaminant concentrations.

  9. Temporal and spatial distributions of contaminants in sediments of Santa Monica Bay, California

    Science.gov (United States)

    Bay, S.M.; Zeng, E.Y.; Lorenson, T.D.; Tran, K.; Alexander, Corrine

    2003-01-01

    Contaminant inputs from wastewater discharge, a major source of contamination to Santa Monica Bay (SMB), have declined drastically during the last three decades as a result of improved treatment processes and better source control. To assess the concomitant temporal changes in the SMB sediments, a study was initiated in June 1997, in which 25 box cores were collected using a stratified random sampling design. Five sediment strata corresponding to the time intervals of 1890-1920, 1932-1963, 1965-1979, 1979-1989, and 1989-1997 were identified using 210Pb dating techniques. Samples from each stratum were analyzed for metals, 1,1,1-Trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites (DDTs), polychlorinated biphenyls (PCBs), and total organic carbon (TOC). Samples from the 1965-1979, 1979-1989, and 1989-1997 strata were also analyzed for polycyclic aromatic hydrocarbons (PAHs) and linear alkylbenzenes (LABs). Sediment metal concentrations increased from 1890-1979 and were similar during the time intervals of 1965-1979, 1979-1989, and 1989-1997, although the mass emissions of trace metals from sewage inputs declined substantially during the same time period. Trace organic contamination in SMB was generally highest in sediments corresponding to deposition during the years of 1965-1979 or 1979-1989 and showed a decline in concentration in the 1989-1997 stratum. Temporal trends of contamination were greatest in sediments collected from areas near the Hyperion Treatment Plant (HTP) outfall system and on the slope of Redondo Canyon. The highest contaminant concentrations were present in sediments near the HTP 7-mile outfall in the 1965-1979 stratum. Elevated trace metal and organic concentrations were still present in the 1989-1997 stratum of most stations, suggesting that sediment contaminants have moved vertically in the sediment column since sludge discharges from the 7-mile outfall (a dominant source of contamination to the bay) ceased in 1987. The

  10. Contaminants in surface water and sediments near the Tynagh silver mine site, County Galway, Ireland

    Energy Technology Data Exchange (ETDEWEB)

    O' Neill, A. [School of Planning, Architecture and Civil Engineering, Queen' s University of Belfast, Belfast, Northern Ireland (United Kingdom); Phillips, D.H., E-mail: d.phillips@qub.ac.uk [School of Planning, Architecture and Civil Engineering, Queen' s University of Belfast, Belfast, Northern Ireland (United Kingdom); Bowen, J. [School of Planning, Architecture and Civil Engineering, Queen' s University of Belfast, Belfast, Northern Ireland (United Kingdom); Sen Gupta, B. [School of the Built Environment, Hariot-Watt University, Edinburgh, Scotland (United Kingdom)

    2015-04-15

    A former silver mine in Tynagh, Co. Galway, Ireland is one of the most contaminated mine sites in Europe with maximum concentrations of Zn, As, Pb, Mn, Ni, Cu, and Cd far exceeding guideline values for water and sediment. The aims of this research were to 1) further assess the contamination, particularly metals, in surface water and sediment around the site, and 2) determine if the contamination has increased 10 years after the Environmental Protection Agency Ireland (EPAI) identified off-site contamination. Site pH is alkaline to neutral because CaCO{sub 3}-rich sediment and rock material buffer the exposed acid generating sulphide-rich ore. When this study was compared to the previous EPAI study conducted 10 years earlier, it appeared that further weathering of exposed surface sediment had increased concentrations of As and other potentially toxic elements. Water samples from the tailings ponds and adjacent Barnacullia Stream had concentrations of Al, Cd, Mn, Zn and Pb above guideline values. Lead and Zn concentrations from the tailings pond sediment were 16 and 5 times higher, respectively, than concentrations reported 10 years earlier. Pb and Zn levels in most sediment samples exceeded the Expert Group (EGS) guidelines of 1000 and 5000 mg/kg, respectively. Arsenic concentrations were as high as 6238 mg/kg in the tailings ponds sediment, which is 62 and 862 times greater than the EGS and Canadian Soil Quality Guidelines (CSQG), respectively. Cadmium, Cu, Fe, Mn, Pb and Zn concentrations in water and sediment were above guideline values downstream of the site. Additionally, Fe, Mn and organic matter (OM) were strongly correlated and correlated to Zn, Pb, As, Cd, Cu and Ni in stream sediment. Therefore, the nearby Barnacullia Stream is also a significant pathway for contaminant transport to downstream areas. Further rehabilitation of the site may decrease the contamination around the area. - Highlights: • Tynagh silver mine in Co. Galway, Ireland is a source of

  11. Multivariate analysis of heavy metal contamination using river sediment cores of Nankan River, northern Taiwan

    Science.gov (United States)

    Lee, An-Sheng; Lu, Wei-Li; Huang, Jyh-Jaan; Chang, Queenie; Wei, Kuo-Yen; Lin, Chin-Jung; Liou, Sofia Ya Hsuan

    2016-04-01

    Through the geology and climate characteristic in Taiwan, generally rivers carry a lot of suspended particles. After these particles settled, they become sediments which are good sorbent for heavy metals in river system. Consequently, sediments can be found recording contamination footprint at low flow energy region, such as estuary. Seven sediment cores were collected along Nankan River, northern Taiwan, which is seriously contaminated by factory, household and agriculture input. Physico-chemical properties of these cores were derived from Itrax-XRF Core Scanner and grain size analysis. In order to interpret these complex data matrices, the multivariate statistical techniques (cluster analysis, factor analysis and discriminant analysis) were introduced to this study. Through the statistical determination, the result indicates four types of sediment. One of them represents contamination event which shows high concentration of Cu, Zn, Pb, Ni and Fe, and low concentration of Si and Zr. Furthermore, three possible contamination sources of this type of sediment were revealed by Factor Analysis. The combination of sediment analysis and multivariate statistical techniques used provides new insights into the contamination depositional history of Nankan River and could be similarly applied to other river systems to determine the scale of anthropogenic contamination.

  12. Coal tar in dermatology

    Energy Technology Data Exchange (ETDEWEB)

    Roelofzen, J.H.J.; Aben, K.K.H.; Van Der Valk, P.G.M.; Van Houtum, J.L.M.; Van De Kerkhof, P.C.M.; Kiemeney, L.A.L.M. [Radboud University Nijmegen Medical Center, Nijmegen (Netherlands). Dept. of Dermatology

    2007-07-01

    Coal tar is one of the oldest treatments for psoriasis and eczema. It has anti-inflammatory, antibacterial, antipruritic and antimitotic effects. The short-term side effects are folliculitis, irritation and contact allergy. Coal tar contains carcinogens. The carcinogenicity of coal tar has been shown in animal studies and studies in occupational settings. There is no clear evidence of an increased risk of skin tumors or internal tumors. Until now, most studies have been fairly small and they did not investigate the risk of coal tar alone, but the risk of coal tar combined with other therapies. New, well-designed, epidemiological studies are necessary to assess the risk of skin tumors and other malignancies after dermatological use of coal tar.

  13. Long-term distribution of Cs-137 in freshwater ecosystem and the effect of bioturbation on leakage of Cs-137 from the sediments

    International Nuclear Information System (INIS)

    Aquilonius, K.

    1995-06-01

    The first aim of the project was to make a literature compilation regarding Cs-137 in freshwater systems. Secondly, in order to follow up the long-term behaviour of Cs-137 in Lake Hillesjoen, sediment and water was sampled with respect to Cs-137. Finally, an experiment was done with chironomids, with the aim to assess the impact of bioturbation on the leakage of Cs-137 from the sediment, since this is one of the factors contributing to the uncertainties in radioecological models. Some aspects of long-term distribution of Cs-137 in freshwater lakes is discussed. In lake Hillesjoen the pool of Cs-137 in sediments (225 kBq/m 2 , 1993) has gradually increased since the Chernobyl accident, and now exceeds the initial deposition (100 kBq/m 2 ). The effect of bioturbation on the leakage from the sediment to the water could not be clarified in this experiment, but is discussed. 40 refs

  14. Pattern recognition on X-ray fluorescence records from Copenhagen lake sediments using principal component analysis

    DEFF Research Database (Denmark)

    Schreiber, Norman; Garcia, Emanuel; Kroon, Aart

    2014-01-01

    Principle Component Analysis (PCA) was performed on chemical data of two sediment cores from an urban fresh-water lake in Copenhagen, Denmark. X-ray fluorescence (XRF) core scanning provided the underlying datasets on 13 variables (Si, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Cd, Pb). Principle......, Fe, Rb) and characterized the content of minerogenic material in the sediment. In case of both cores, PC2 was a good descriptor emphasized as the contamination component. It showed strong linkages with heavy metals (Cu, Zn, Pb), disclosing changing heavy-metal contamination trends across different...

  15. Options for In Situ Capping of Palos Verdes Shelf Contaminated Sediments

    National Research Council Canada - National Science Library

    Palermo, Michael; Schroeder, Paul; Rivera, Yilda; Ruiz, Carlos; Clarke, Doug; Gailani, Joe; Clausner, James; Hynes, Mary; Fredette, Thomas; Tardy, Barbara

    1999-01-01

    The U.S. Army Engineer Waterways Experiment Station (WES) has performed an evaluation of in situ capping options for sediment restoration of DDT and PCB contaminated sediments on the Palos Verdes (PV...

  16. Factors influencing mercury in freshwater surface sediments of northeastern North America

    Science.gov (United States)

    Kamman, N.C.; Chalmers, A.; Clair, T.A.; Major, A.; Moore, R.B.; Norton, S.A.; Shanley, J.B.

    2005-01-01

    We report on an inventory and analysis of sediment mercury (Hg) concentrations from 579 sites across northeastern North America. Sediment Hg concentrations ranged from the limit of detection ca. 0.01-3.7 ??g g -1 (dry weight, d.w.), and the average concentration was 0.19 ??g g-1 (d.w.) Sediment methylmercury concentrations ranged from 0.15 to 21 ng g-1 (d.w.) and the mean concentration was 3.83 ng g -1 (d.w.). Total Hg concentrations (HgT) were greatest in lakes > reservoirs > rivers, although the proportion of Hg as methylmercury showed an inverse pattern. Total Hg was weakly and positively correlated with the sediment organic matter and percent of watershed as forested land, and weakly and negatively correlated with sediment solids content, drainage area, and agricultural land. Sediment methylmercury concentrations were weakly and positively correlated to wetland area, and weakly and negatively correlated to drainage area. Methylmercury, expressed as a percentage of HgT was positively correlated to agricultural land area. For sites with co-located sediment and fish-tissue sampling results, there was no relationship between sediment Hg and fish-tissue Hg. Finally, our data indicate that at least 44% of waters across the region have sediment HgT concentrations in excess of Canadian and United States minimum sediment contaminant guidelines for the protection of aquatic biota. ?? 2005 Springer Science+Business Media, Inc.

  17. Submerged macrophytes modify bacterial community composition in sediments in a large, shallow, freshwater lake.

    Science.gov (United States)

    Zhao, Da-Yong; Liu, Peng; Fang, Chao; Sun, Yi-Meng; Zeng, Jin; Wang, Jian-Qun; Ma, Ting; Xiao, Yi-Hong; Wu, Qinglong L

    2013-04-01

    Submerged aquatic macrophytes are an important part of the lacustrine ecosystem. In this study, the bacterial community compositions in the rhizosphere sediments from three kinds of submerged macrophytes (Ceratophyllum demersum, Potamogeton crispus, and Vallisneria natans) were investigated to determine whether submerged macrophytes could drive the variation of bacterial community in the eutrophic Taihu Lake, China. Molecular techniques, including terminal restriction fragment length polymorphism (T-RFLP) of PCR-amplified 16S rRNA gene and clone libraries, were employed to analyze the bacterial community compositions. Remarkable differences of the T-RFLP patterns were observed among the different samples, and the results of LIBSHUFF analysis also confirmed that the bacterial community compositions in the rhizosphere sediments of three kinds of submerged macrophytes were statistically different from that of the unvegetated sediment. Acidobacteria, Deltaproteobacteria, and Betaproteobacteria were the dominant bacterial groups in the rhizosphere sediments of Ceratophyllum demersum, Potamogeton crispus, and Vallisneria natans, respectively, accounting for 15.38%, 29.03%, and 18.00% of the total bacterial abundances. Our study demonstrated that submerged macrophytes could influence the bacterial community compositions in their rhizosphere sediments, suggesting that macrophytes have an effect on the cycling and transportation of nutrients in the freshwater lake ecosystem.

  18. Levels and distribution of polybrominated diphenyl ethers (PBDEs) in the freshwater environment surrounding a PBDE manufacturing plant in China

    International Nuclear Information System (INIS)

    Xu Jie; Gao Zishen; Xian Qiming; Yu Hongxia; Feng Jianfang

    2009-01-01

    Polybrominated diphenyl ethers (PBDEs) were determined in muscle, liver and eggs of freshwater fishes and surface sediments from the Nongkang River in Jinhu, Jiangsu Province, China. The present study is the first to report PBDE concentrations in the freshwater environment surrounding a PBDE manufacturing plant in China. The concentrations of 13 PBDE congeners in muscle, liver and eggs of freshwater fishes ranged from < LOD to 130, < LOD to 252 and < LOD to 33.3 ng/g lipid wt, respectively, while the concentrations of 13 PBDE congeners in surface sediments from sewage outfall, upstream and downstream of the river were 52, 9.2, 7.1 ng/g organic carbon wt, respectively. Contamination by PBDEs in this area was not serious when compared with other regions of the world. A relatively high proportion of BDE-183 was found, consistent with the octa-BDE technical mixtures from the manufacturing plant by the side of the river. - The first study to report concentrations of PBDEs in the freshwater environment surrounding a PBDE manufacturing plant in China.

  19. Phytoremediation prospects of willow stands on contaminated sediment: a field trial

    International Nuclear Information System (INIS)

    Vervaeke, P.; Luyssaert, S.; Mertens, J.; Meers, E.; Tack, F.M.G.; Lust, N.

    2003-01-01

    A field trial indicated increased degradation of mineral oil in sediments planted with willow. - Establishing fast growing willow stands on land disposed contaminated dredged sediment can result in the revaluation of this material and opens possibilities for phytoremediation. A field trial was designed to assess the impact of planting a willow stand (Salix viminalis L. 'Orm') on the dissipation of organic contaminants (mineral oil and PAHs) in dredged sediment. In addition, the accumulation of heavy metals (Cd, Cu, Pb and Zn) in the biomass was determined. After 1.5 years, a significant decrease of 57% in the mineral oil concentration in the sediment planted with willow was observed. Degradation of mineral oil in sediment which was left fallow, was only 15%. The mineral oil degradation under willow was most pronounced (79%) in the root zone of the stand. In the sediment which was left fallow there was a significant reduction of the total PAH content by 32% compared with a 23% reduction in the planted sediment. The moderate and selective metal uptake, measured in this study, limits the prospects for phytoextraction of metals from dredged sediment

  20. Phytoremediation prospects of willow stands on contaminated sediment: a field trial

    Energy Technology Data Exchange (ETDEWEB)

    Vervaeke, P.; Luyssaert, S.; Mertens, J.; Meers, E.; Tack, F.M.G.; Lust, N

    2003-11-01

    A field trial indicated increased degradation of mineral oil in sediments planted with willow. - Establishing fast growing willow stands on land disposed contaminated dredged sediment can result in the revaluation of this material and opens possibilities for phytoremediation. A field trial was designed to assess the impact of planting a willow stand (Salix viminalis L. 'Orm') on the dissipation of organic contaminants (mineral oil and PAHs) in dredged sediment. In addition, the accumulation of heavy metals (Cd, Cu, Pb and Zn) in the biomass was determined. After 1.5 years, a significant decrease of 57% in the mineral oil concentration in the sediment planted with willow was observed. Degradation of mineral oil in sediment which was left fallow, was only 15%. The mineral oil degradation under willow was most pronounced (79%) in the root zone of the stand. In the sediment which was left fallow there was a significant reduction of the total PAH content by 32% compared with a 23% reduction in the planted sediment. The moderate and selective metal uptake, measured in this study, limits the prospects for phytoextraction of metals from dredged sediment.

  1. Uranium Phases in Contaminated Sediments Below Hanford's U Tank Farm

    International Nuclear Information System (INIS)

    Um, Wooyong; Wang, Zheming; Serne, R. Jeffrey; Williams, Benjamin D.; Brown, Christopher F.; Dodge, Cleveland J.; Francis, Arokiasamy J.

    2009-01-01

    Macroscopic and spectroscopic investigations (XAFS, XRF and TRLIF) on Hanford contaminated vadose zone sediments from the U-tank farm showed that U(VI) exists as different surface phases as a function of depth below ground surface (bgs). Dominant U(VI) silicate precipitates (boltwoodite and uranophane) were present in shallow-depth sediments (15-16 m bgs). In the intermediate depth sediments (20-25 m bgs), adsorbed U(VI) phases dominated but small amounts of surface precipitates consisting of polynuclear U(VI) surface complex were also identified. The deep depth sediments (> 28 m bgs) showed no signs of contact with tank wastes containing Hanford-derived U(VI), but natural uranium solid phases were observed. Most of the U(VI) was preferentially associated with the silt and clay size fractions and showed strong correlation with Ca, especially for the precipitated U(VI) silicate phase in the shallow depth sediments. Because U(VI) silicate precipitates dominate the U(VI) phases in the shallow depth sediments, macroscopic (bi)carbonate leaching should result in U(VI) releases from both desorption and dissolution processes. Having several different U(VI) surface phases in the Hanford contaminated sediments indicates that the U(VI) release mechanism could be complicated and that detailed characterization of the sediments would be needed to estimate U(VI) fate and transport in vadose zone

  2. Assessment of Trace Metals Contamination of Surface Water and Sediment: A Case Study of Mvudi River, South Africa

    Directory of Open Access Journals (Sweden)

    Joshua N. Edokpayi

    2016-02-01

    Full Text Available Trace metals contamination of rivers and sediments remains a global threat to biodiversity and humans. This study was carried out to assess the variation pattern in trace metals contamination in Mvudi River water and sediments for the period of January–June 2014. Metal concentrations were analyzed using an inductively-coupled plasma optical emission spectrometer after nitric acid digestion. A compliance study for the water samples was performed using the guidelines of the Department of Water Affairs and Forestry (DWAF of South Africa and the World Health Organization (WHO. The National Oceanic and Atmospheric Administration (NOAA sediment quality guidelines for marine and estuarine sediments and the Canadian Council of Ministers of the Environment sediment guidelines (CCME for freshwater sediments were used to determine the possible toxic effects of the metals on aquatic organisms. pH (7.2–7.7 and conductivity (10.5–16.1 mS/m values complied with DWAF and WHO standards for domestic water use. Turbidity values in nephelometric turbidity units (NTU were in the range of 1.9–429 and exceeded the guideline values. The monthly average levels of trace metals in the water and sediments of Mvudi River were in the range of: Al (1.01–9.644 mg/L and 4296–5557 mg/kg, Cd (0.0003–0.002 mg/L and from below the detection limit to 2.19 mg/kg, Cr (0.015–0.357 mg/L and 44.23–149.52 mg/kg, Cu (0.024–0.185 mg/L and 13.22–1027 mg/kg, Fe (0.702–2.645 mg/L and 3840–6982 mg/kg, Mn (0.081–0.521 mg/L and 279–1638 mg/kg, Pb (0.002–0.042 mg/L and 1.775-4.157 mg/kg and Zn (0.031–0.261 mg/L and 14.481–39.88 mg/kg. The average concentrations of Al, Cr, Fe, Mn and Pb in the water samples exceeded the recommended guidelines of DWAF and WHO for domestic water use. High concentrations of Al and Fe were determined in the sediment samples. Generally, the concentrations of Cd, Cr and Cu in the sediments exceeded the corresponding effect range low

  3. Treatment of lignite tars, etc

    Energy Technology Data Exchange (ETDEWEB)

    1936-08-07

    A process is described for treating tars such as lignite tar, shale tar, or peat tar, and similar tars, characterized by the fact that the tar is rectified to about 240/sup 0/C and the residue brought to a temperature above 50/sup 0/C after diluting with a product of the type of gasoline or ligroin at about 30/sup 0/C and treated with selective solvents preferably low-boiling phenols and eventually with water.

  4. Effect of sulfate and nitrate on acetate conversion by anaerobic microorganisms in a freshwater sediment.

    Science.gov (United States)

    Scholten, Johannes C M; Bodegom, Peter M; Vogelaar, Jaap; Ittersum, Alexander; Hordijk, Kees; Roelofsen, Wim; Stams, Alfons J M

    2002-12-01

    Acetate is quantitatively the most important substrate for methane production in a freshwater sediment in The Netherlands. In the presence of alternative electron acceptors the conversion of acetate by methanogens was strongly inhibited. By modelling the results, obtained in experiments with and without (13)C-labelled acetate, we could show that the competition for acetate between methanogens and sulfate reducers is the main cause of inhibition of methanogenesis in the sediment. Although nitrate led to a complete inhibition of methanogenesis, acetate-utilising nitrate-reducing bacteria hardly competed with methanogens for the available acetate in the presence of nitrate. Most-probable-number enumerations showed that methanogens (2x10(8) cells cm(-3) sediment) and sulfate reducers (2x10(8) cells cm(-3) sediment) were the dominant acetate-utilising organisms in the sediment, while numbers of acetate-utilising nitrate reducers were very low (5x10(5) cells cm(-3) sediment). However, high numbers of sulfide-oxidising nitrate reducers were detected. Denitrification might result in the formation of toxic products. We speculate that the accumulation of low concentrations of NO (<0.2 mM) may result in an inhibition of methanogenesis.

  5. Spatial and temporal distribution of microplastics in water and sediments of a freshwater system (Antuã River, Portugal).

    Science.gov (United States)

    Rodrigues, M O; Abrantes, N; Gonçalves, F J M; Nogueira, H; Marques, J C; Gonçalves, A M M

    2018-08-15

    Microplastics (particles with a sizemicroplastics in freshwater systems is less understood than in marine environment. Hence, the present study aims to provide new insights into microplastics abundances and distribution in Antuã River (Portugal) by applying the isolation method of wet peroxide oxidation with addition of zinc chloride to water and sediment samples collected in March and October 2016, in three sampling sites. The abundance of microplastics in water ranged from 5 to 8.3mgm -3 or 58-193itemsm -3 in March and from 5.8-51.7mgm -3 or 71-1265itemsm -3 in October. In sediments, the abundance ranged from 13.5-52.7mgkg -1 or 100-629itemskg -1 in March and from 2.6-71.4mgkg -1 or 18-514itemskg -1 in October. The water and sediment samples with the greatest abundances were from São João da Madeira and Aguincheira, respectively. Spatio-temporal distribution showed different pattern according to methodological approaches, seasonal and hydrodynamic conditions and the proximity to urban/industry areas. Analysis of plastics by Fourier transform infrared spectroscopy underline polyethylene and polypropylene as the most common polymer types identified in this work. The low medium high oxidation ratio was 56:22:22 (%) in March and 61:31:8 (%) in October. Foams and fibers were the most abundant type in São João da Madeira, while fibers and fragments were the most abundant in Aguincheira and Estarreja in water and sediment samples, respectively. This study emphasizes the importance of rivers as carriage systems of microplastics. Further studies should be performed to identify point sources in order to mitigate the microplastics contamination in aquatic systems. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Assessing sediment contamination using six toxicity assays

    Directory of Open Access Journals (Sweden)

    Allen G. BURTON Jr.

    2001-08-01

    Full Text Available An evaluation of sediment toxicity at Lake Orta, Italy was conducted to compare a toxicity test battery of 6 assays and to evaluate the extent of sediment contamination at various sediment depths. Lake Orta received excessive loadings of copper and ammonia during the 1900’s until a large remediation effort was conducted in 1989-90 using lime addition. Since that time, the lake has shown signs of a steady recovery of biological communities. The study results showed acute toxicity still exists in sediments at a depth of 5 cm and greater. Assays that detected the highest levels of toxicity were two whole sediment exposures (7 d using Hyalella azteca and Ceriodaphnia dubia. The MicrotoxR assay using pore water was the third most sensitive assay. The Thamnotox, Rototox, Microtox solid phase, and Seed Germination-Root Elongation (pore and solid phase assays showed occasional to no toxicity. Based on similarity of responses and assay sensitivity, the two most useful assays were the C. dubia (or H. azteca and Microtox pore water. These assays were effective at describing sediment toxicity in a weight-of-evidence approach.

  7. Dominance of sulfur-fueled iron oxide reduction in low-sulfate freshwater sediments.

    Science.gov (United States)

    Hansel, Colleen M; Lentini, Chris J; Tang, Yuanzhi; Johnston, David T; Wankel, Scott D; Jardine, Philip M

    2015-11-01

    A central tenant in microbial biogeochemistry is that microbial metabolisms follow a predictable sequence of terminal electron acceptors based on the energetic yield for the reaction. It is thereby oftentimes assumed that microbial respiration of ferric iron outcompetes sulfate in all but high-sulfate systems, and thus sulfide has little influence on freshwater or terrestrial iron cycling. Observations of sulfate reduction in low-sulfate environments have been attributed to the presumed presence of highly crystalline iron oxides allowing sulfate reduction to be more energetically favored. Here we identified the iron-reducing processes under low-sulfate conditions within columns containing freshwater sediments amended with structurally diverse iron oxides and fermentation products that fuel anaerobic respiration. We show that despite low sulfate concentrations and regardless of iron oxide substrate (ferrihydrite, Al-ferrihydrite, goethite, hematite), sulfidization was a dominant pathway in iron reduction. This process was mediated by (re)cycling of sulfur upon reaction of sulfide and iron oxides to support continued sulfur-based respiration--a cryptic sulfur cycle involving generation and consumption of sulfur intermediates. Although canonical iron respiration was not observed in the sediments amended with the more crystalline iron oxides, iron respiration did become dominant in the presence of ferrihydrite once sulfate was consumed. Thus, despite more favorable energetics, ferrihydrite reduction did not precede sulfate reduction and instead an inverse redox zonation was observed. These findings indicate that sulfur (re)cycling is a dominant force in iron cycling even in low-sulfate systems and in a manner difficult to predict using the classical thermodynamic ladder.

  8. Assessment, modelization and analysis of 106 Ru experimental transfers through a freshwater trophic system

    International Nuclear Information System (INIS)

    Vray, F.

    1994-01-01

    Experiments are carried out in order to study 106 RU transfers through a freshwater ecosystem including 2 abiotic compartments (water and sediment) and 3 trophic levels (10 species). Experimental results are expressed mathematically so as they can be included into a global model which is then tested in two different situations. The comparison of the available data concerning the in situ measured concentrations to the corresponding calculated ones validates the whole procedure. Analysis of the so validated results lightens ruthenium distribution process in the environment. The rare detection of this radionuclide in organisms living in areas contaminated by known meaningful releases can be explained by a relativity high detection limit and by a slight role of the sediment as a secondary contamination source. (author). 78 figs., 18 tabs

  9. Conceptual Site Model for Newark Bay—Hydrodynamics and Sediment Transport

    Directory of Open Access Journals (Sweden)

    Parmeshwar L. Shrestha

    2014-02-01

    Full Text Available A conceptual site model (CSM has been developed for the Newark Bay Study Area (NBSA as part of the Remedial Investigation/Feasibility Study (RI/FS for this New Jersey site. The CSM is an evolving document that describes the influence of physical, chemical and biological processes on contaminant fate and transport. The CSM is initiated at the start of a project, updated during site activities, and used to inform sampling and remediation planning. This paper describes the hydrodynamic and sediment transport components of the CSM for the NBSA. Hydrodynamic processes are influenced by freshwater inflows, astronomical forcing through two tidal straits, meteorological conditions, and anthropogenic activities such as navigational dredging. Sediment dynamics are driven by hydrodynamics, waves, sediment loading from freshwater sources and the tidal straits, sediment size gradation, sediment bed properties, and particle-to-particle interactions. Cohesive sediment transport is governed by advection, dispersion, aggregation, settling, consolidation, and erosion. Noncohesive sediment transport is governed by advection, dispersion, settling, armoring, and transport in suspension and along the bed. The CSM will inform the development and application of a numerical model that accounts for all key variables to adequately describe the NBSA’s historical, current, and future physical conditions.

  10. Effects-based spatial assessment of contaminated estuarine sediments from Bear Creek, Baltimore Harbor, MD, USA.

    Science.gov (United States)

    Hartzell, Sharon E; Unger, Michael A; McGee, Beth L; Wilson, Sacoby M; Yonkos, Lance T

    2017-10-01

    Estuarine sediments in regions with prolonged histories of industrial activity are often laden to significant depths with complex contaminant mixtures, including trace metals and persistent organic pollutants. Given the complexity of assessing risks from multi-contaminant exposures, the direct measurement of impacts to biological receptors is central to characterizing contaminated sediment sites. Though biological consequences are less commonly assessed at depth, laboratory-based toxicity testing of subsurface sediments can be used to delineate the scope of contamination at impacted sites. The extent and depth of sediment toxicity in Bear Creek, near Baltimore, Maryland, USA, was delineated using 10-day acute toxicity tests with the estuarine amphipod Leptocheirus plumulosus, and chemical analysis of trace metals and persistent organic pollutants. A gradient of toxicity was demonstrated in surface sediments with 21 of 22 tested sites differing significantly from controls. Effects were most pronounced (100% lethality) at sites proximate to a historic industrial complex. Sediments from eight of nine core samples to depths of 80 cm were particularly impacted (i.e., caused significant lethality to L. plumulosus) even in locations overlain with relatively non-toxic surface sediments, supporting a conclusion that toxicity observed at the surface (top 2 cm) does not adequately predict toxicity at depth. In seven of nine sites, toxicity of surface sediments differed from toxicity at levels beneath by 28 to 69%, in five instances underestimating toxicity (28 to 69%), and in two instances overestimating toxicity (44 to 56%). Multiple contaminants exceeded sediment quality guidelines and correlated positively with toxic responses within surface sediments (e.g., chromium, nickel, polycyclic aromatic hydrocarbon (PAH), total petroleum hydrocarbon). Use of an antibody-based PAH biosensor revealed that porewater PAH concentrations also increased with depth at most sites. This

  11. Indian coal tars. II

    Energy Technology Data Exchange (ETDEWEB)

    Basu, A N; Bhatnagar, J N; Roy, A K

    1954-01-01

    Laboratory experiments were carried out on these efforts: (1) rank and specific-gravity fractions on tar yield; (2) addition of water to the coal charge, or steam during carbonization, on yield of tar and tar acids; (3) the presence of a cracking agent (shale) with and without steam addition on the yield of tar and tar acids (the particular shale used without steam reduced the yield, and the restricted use of steam brought the yield to the former noncatalyzed level); and (4) catalytic effect of three different samples of shale, firebrick, quartz, coke, and silica-alumina on the cracking of tar acids (the most active were two of the shales, a freshly-prepared coke, and the Al/sub 2/O/sub 3/-SiO/sub 2/ catalysts that gave conversion up to 98%). The products were mainly carbon, aromatic hydrocarbons of the naphthalene series and gases (CO and H/sub 2/). The yield of the tar becomes less as coal of lower specific gravity is used or when higher temperatures are used for carbonization. The mineral matter associated with Indian coals acts as a decomposition catalyst for tar acids, as shown by experiments on the decomposition of PhOH at temperatures above 800/sup 0/.

  12. Tracking the origin and dispersion of contaminated sediments transported by rivers draining the Fukushima radioactive contaminant plume

    Directory of Open Access Journals (Sweden)

    H. Lepage

    2015-03-01

    Full Text Available This study was conducted in several catchments draining the main Fukushima Dai-ichi Power Plant contaminant plume in Fukushima prefecture, Japan. We collected soils and sediment drape deposits (n = 128 and investigated the variation in 137Cs enrichment during five sampling campaigns, conducted every six months, which typically occurred after intense erosive events such as typhoons and snowmelt. We show that upstream contaminated soils are eroded during summer typhoons (June–October before being exported during the spring snowmelt (March–April. However, this seasonal cycle of sediment dispersion is further complicated by the occurrence of dam releases that may discharge large amounts of contaminants to the coastal plains during the coming years.

  13. ACTIVE CAPPING TECHNOLOGY - NEW APPROACHES FOR IN SITU REMEDIATION OF CONTAMINATED SEDIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A.; Paller, M.; Roberts, J.

    2012-02-13

    This study evaluated pilot-scale active caps composed of apatite, organoclay, biopolymers, and sand for the remediation of metal-contaminated sediments. The active caps were constructed in Steel Creek, at the Savannah River Site near Aiken, South Carolina. Monitoring was conducted for 12 months. Effectiveness of the caps was based on an evaluation of contaminant bioavailability, resistance to erosion, and impacts on benthic organisms. Active caps lowered metal bioavailability in the sediment during the one-year test period. Biopolymers reduced sediment suspension during cap construction, increased the pool of carbon, and lowered the release of metals. This field validation showed that active caps can effectively treat contaminants by changing their speciation, and that caps can be constructed to include more than one type of amendment to achieve multiple goals.

  14. Tar bases in low-temperature coal tar

    Energy Technology Data Exchange (ETDEWEB)

    Sugiura, S; Ueno, H; Yokoyama, H

    1951-01-01

    Tar bases were extracted from three fractions, that boil below 260/sup 0/ at 260/sup 0/ to 280/sup 0/, and 280/sup 0/ to 330/sup 0/, respectively, of the low-temperature tar obtained by the carbonization of Ube coal in a Koppers' vertical retort at approximately 750/sup 0/. These were divided, respectively, into three groups, acetate-forming amine, HCl salt-forming bases (I), and CHCl/sub 3/-soluble bases (II), and further fractionally distilled. From the physical and chemical properties of the fractions thus obtained, it was concluded that low-temperature coal tar contained no low boiling pyridine homologues and that, besides higher homologues of pyridine, nonaromatic, more saturated, and less basic compounds of larger atomic weight and smaller refractive index, such as derivatives of pyrrole and indole, also existed as in crude petroleum.

  15. EVALUATION OF THE STATE-OF-THE-ART CONTAMINATED SEDIMENT TRANSPORT AND FATE MODELING SYSTEM

    Science.gov (United States)

    Modeling approaches for evaluating the transport and fate of sediment and associated contaminants are briefly reviewed. The main emphasis is on: 1) the application of EFDC (Environmental Fluid Dynamics Code), the state-of-the-art contaminated sediment transport and fate public do...

  16. Radioactive contamination of the Balchug (Upper Yenisey) floodplain, Russia in relation to sedimentation processes and geomorphology.

    Science.gov (United States)

    Linnik, V G; Brown, J E; Dowdall, M; Potapov, V N; Surkov, V V; Korobova, E M; Volosov, A G; Vakulovsky, S M; Tertyshnik, E G

    2005-03-01

    The radioactive contamination of a riverine floodplain, heavily influenced by discharges from Krasnoyarsk-26, has been studied with respect to sedimentation processes and the geomorphology of the Upper Yenisey floodplain. The study was effected by implementation of a regime of in situ observations and measurements, sampling, and the interpretation of satellite images. The results of the study indicate that on the Balchug Bypass Floodplain, radionuclide contamination is primarily influenced by the thickness of the deposited sediments, and the area can be considered as two depositional environments. The Balchug floodplain area was contaminated due to sedimentation of radionuclide-contaminated alluvium, whose depositional regime significantly changed after the construction of a hydroelectric power station in 1967. Contamination levels are lower on the upstream part of the floodplain where sediment depth is less than 0.2-0.3 m, and this contamination started to accumulate in 1967, while the downstream part of the floodplain, exhibiting deeper deposits, displays higher levels of radionuclide contamination because radionuclides began to deposit here in 1958 when the Krasnoyarsk-26 Mining and Chemical Combine (KMCC) commenced operation. Radionuclide contamination of the floodplain is also related to the elevation of the floodplain, higher regions of the floodplain typically having lower contamination than low-lying areas, which tend to be frequently inundated with sediments being deposited during such inundations. Local relief, its orientation, and vegetation cover have also combined to form sediment traps with significantly higher radionuclide contamination. Lithological analysis combined with radiometric assay indicates a total 137Cs floodplain inventory of 33.7 GBq.

  17. Radioactive contamination of the Balchug (Upper Yenisey) floodplain, Russia, in relation to sedimentation processes and geomorphology

    International Nuclear Information System (INIS)

    Linnik, V.G.; Korobova, E.M.; Volosov, A.G.; Brown, J.E.; Dowdall, M.; Potapov, V.N.; Surkov, V.V.; Vakulovsky, S.M.; Tertyshnik, E.G.

    2005-01-01

    The radioactive contamination of a riverine floodplain, heavily influenced by discharges from Krasnoyarsk-26, has been studied with respect to sedimentation processes and the geomorphology of the Upper Yenisey floodplain. The study was effected by implementation of a regime of in situ observations and measurements, sampling, and the interpretation of satellite images. The results of the study indicate that on the Balchug Bypass Floodplain, radionuclide contamination is primarily influenced by the thickness of the deposited sediments, and the area can be considered as two depositional environments. The Balchug floodplain area was contaminated due to sedimentation of radionuclide-contaminated alluvium, whose depositional regime significantly changed after the construction of a hydroelectric power station in 1967. Contamination levels are lower on the upstream part of the floodplain where sediment depth is less than 0.2-0.3 m, and this contamination started to accumulate in 1967, while the downstream part of the floodplain, exhibiting deeper deposits, displays higher levels of radionuclide contamination because radionuclides began to deposit here in 1958 when the Krasnoyarsk-26 Mining and Chemical Combine (KMCC) commenced operation. Radionuclide contamination of the floodplain is also related to the elevation of the floodplain, higher regions of the floodplain typically having lower contamination than low-lying areas, which tend to be frequently inundated with sediments being deposited during such inundations. Local relief, its orientation, and vegetation cover have also combined to form sediment traps with significantly higher radionuclide contamination. Lithological analysis combined with radiometric assay indicates a total 137 Cs floodplain inventory of 33.7 GBq

  18. Metal availability in a highly contaminated, dredged-sediment disposal site: field measurements and geochemical modeling.

    Science.gov (United States)

    Lions, Julie; Guérin, Valérie; Bataillard, Philippe; van der Lee, Jan; Laboudigue, Agnès

    2010-09-01

    Two complementary approaches were used to characterize arsenic and metal mobilizations from a dredged-sediment disposal site: a detailed field study combined with hydrogeochemical modeling. Contaminants in sediments were found to be mainly present as sulfides subject to oxidation. Secondary phases (carbonates, sulfates, (hydr)oxides) were also observed. Oxidative processes occurred at different rates depending on physicochemical conditions and contaminant contents in the sediment. Two distinct areas were identified on the site, each corresponding to a specific contaminant mobility behavior. In a reducing area, Fe and As were highly soluble and illustrated anoxic behavior. In well-oxygenated material, groundwater was highly contaminated in Zn, Cd and Pb. A third zone in which sediments and groundwater were less contaminated was also characterized. This study enabled us to prioritize remediation work, which should aim to limit infiltration and long-term environmental impact. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  19. A field study on phytoremediation of dredged sediment contaminated by heavy metals and nutrients: the impacts of sediment aeration.

    Science.gov (United States)

    Wu, Juan; Yang, Lihua; Zhong, Fei; Cheng, Shuiping

    2014-12-01

    Compared to traditional chemical or physical treatments, phytoremediation has proved to be a cost-effective and environmentally sound alternative for remediation of contaminated dredged sediment. A field study was conducted in a sediment disposal site predominantly colonized by Typha angustifolia under different sediment moisture conditions to estimate the phytoremediation effects of dredged sediment. The moisture content was 37.30 % and 48.27 % in aerated and waterlogged sediment, respectively. Total nitrogen (TN) content was higher in the waterlogged sediment than in the aerated sediment. The total Cd contents were lower in aerated sediment, which was mainly resulted from the lower exchangeable fraction of Cd. The bioaccumulation of P, Cu and Pb in T. angustifolia was promoted by waterlogging, and the belowground tissue concentrations and accumulation factors (AFs) of Cu were higher than that of other metals, which can be explained by that Cu is an essential micronutrient for plants. Consistent with many previous studies, T. angustifolia showed higher metal levels in roots than in above-ground tissues at both the sediment conditions. Due to the improved biomass produced in the aerated sediment, the removals of nutrients and the metals by plant harvest were higher from aerated sediment than from waterlogged sediment. It was indicated that maintaining the dredged sediment aerated can avoid release risk and plant uptake of metals, while the opposite management option can promote phytoextraction of these contaminants.

  20. Contamination by persistent toxic substances in surface sediment of urban rivers in Chaohu City, China.

    Science.gov (United States)

    Li, Feipeng; Zhang, Haiping; Meng, Xiangzhou; Chen, Ling; Yin, Daqiang

    2012-01-01

    The concentration and spatial distribution of persistent toxic substances (PTS) in the river sediment in Chaohu City, China were investigated. A total of nine surface sediments were collected and the selected PTS pollutants including six heavy metals and nineteen polybrominated diphenyl ethers (PBDEs) were analyzed. The mean heavy metal concentrations (in mg/kg, dry weight) ranged within 0.18-1.53 (Hg), 50.08-200.18 (Cu), 118.70-313.65 (Zn), 50.77-310.85 (Cr), 37.12-92.72 (Pb) and 13.29-197.24 (As), and Cu, Zn and As have been regarded as the main metal pollutants. The levels of PBDEs (1.2-12.1 ng/g) and BDE-209 (2.4-30.5 ng/g) were at the middle level of the global range. BDE-209 was the predominant congener (67.0%-85.7%), which agrees with the fact that technical deca-BDE mixtures are the dominant PBDE formulation in China. The relative high level of PTS pollutants in the western part of the city is probably owing to the intensive agricultural activities and lack of sewerage system there. The ecological risk assessment with the sediment quality guidelines (SOGs) indicates that the urban river sediments in the city have been heavily contaminated by heavy metals with probable ecotoxicological impacts on freshwater organisms and the main toxic pollutants are Hg and As. The results of current study imply that the city, and perhaps many other small cities in China as well, requires immediate pollution control measures with emphasis on not only conventional organic pollutants but also on PTS such as heavy metals and PBDEs.

  1. Diversity of methanogenic archaea in freshwater sediments of lacustrine ecosystems.

    Science.gov (United States)

    Laskar, Folguni; Das Purkayastha, Sumi; Sen, Aniruddha; Bhattacharya, Mrinal K; Misra, Biswapriya B

    2018-02-01

    About half of the global methane (CH 4 ) emission is contributed by the methanogenic archaeal communities leading to a significant increase in global warming. This unprecedented situation has increased the ever growing necessity of evaluating the control measures for limiting CH 4 emission to the atmosphere. Unfortunately, research endeavors on the diversity and functional interactions of methanogens are not extensive till date. We anticipate that the study of the diversity of methanogenic community is paramount for understanding the metabolic processes in freshwater lake ecosystems. Although there are several disadvantages of conventional culture-based methods for determining the diversity of methanogenic archaeal communities, in order to understand their ecological roles in natural environments it is required to culture the microbes. Recently different molecular techniques have been developed for determining the structure of methanogenic archaeal communities thriving in freshwater lake ecosystem. The two gene based cloning techniques required for this purpose are 16S rRNA and methyl coenzyme M reductase (mcrA) in addition to the recently developed metagenomics approaches and high throughput next generation sequencing efforts. This review discusses the various methods of culture-dependent and -independent measures of determining the diversity of methanogen communities in lake sediments in lieu of the different molecular approaches and inter-relationships of diversity of methanogenic archaea. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. In situ and laboratory bioassays with Chironomus riparius larvae to assess toxicity of metal contamination in rivers: the relative toxic effect of sediment versus water contamination.

    Science.gov (United States)

    Faria, Mafalda S; Lopes, Ricardo J; Nogueira, António J A; Soares, Amadeu M V M

    2007-09-01

    We used bioassays employing head capsule width and body length increase of Chironomus riparius larvae as end points to evaluate metal contamination in streams. Bioassays were performed in situ near an abandoned Portuguese goldmine in the spring of 2003 and 2004. Bioassays also were performed under laboratory conditions with water and sediment collected from each stream to verify if laboratory bioassays could detect in situ toxicity and to evaluate the relative contribution of sediment and water to overall toxicity. We used field sediments with control water and control sediments with field water to discriminate between metal contamination in water and sediment. Field water with dry and sieved, organic matter-free, and nontreated sediments was used to determine the toxicity of heavy metals that enter the organism through ingested material. In both in situ and laboratory bioassays, body length increase was significantly inhibited by metal contamination, whereas head capsule width was not affected. Body length increase was more affected by contaminated sediment compared to contaminated water. The lowest-effect level of heavy metals was observed in the dry and sieved sediment that prevented ingestion of sediment particles by larvae. These results suggest that body length increase of C. riparius larvae can be used to indicate the impact of metal contamination in rivers. Chironomus riparius larvae are more affected by heavy metals that enter the organism through ingested sediment than by heavy metals dissolved in the water column. Nevertheless, several factors, such as the particle size and organic matter of sediment, must be taken into account.

  3. Comparison of five bioassay techniques for assessing sediment-bound contaminants

    OpenAIRE

    Ahlf, Wolfgang; Calmano, Wolfgang; Erhard, Judith; Förstner, Ulrich

    1989-01-01

    Biological response could not be predicted based on chemical concentration of the sediment contaminants. Bioassays integrate the response of test organisms to contaminants and nutrients. Comparative results of five acute bioassays indicated that Neubauer phytoassay was the most sensitive. The mircobial biomass and algal growth tests indicated a response to the availability of contaminants and nutrients. These results suggest the usefulness of a diversity of bioassays in toxicity testing of se...

  4. Dissolution and transport of coal tar compounds in fractured clay-rich residuum

    DEFF Research Database (Denmark)

    Vulava, Vijay M.; McKay, Larry D.; Broholm, Mette Martina

    2012-01-01

    the importance of rapid dissolution and transport through the fracture networks. The concentrations continued to rise but did not reach the corresponding effective solubility limit in most cases. Compounds that were less soluble and those that were more susceptible to sorption or matrix diffusion eluted...... at a much slower rate. Analysis of contaminant concentrations in microcore residuum samples indicated that all 10 compounds had spread throughout the entire monolith and had diffused into the fine-grained matrix between fractures. These data suggest that the predominantly fine pore structure did not appear......We investigated the dissolution and transport of organic contaminants from a crude coal tar mixture in a monolith of fractured clay-rich residuum. An electrolyte solution was eluted through the residuum monolith containing a small emplaced source of coal tar under biologically inhibited and mildly...

  5. Understanding the fate and transport of petroleum hydrocarbons from coal tar within gasholders.

    Science.gov (United States)

    Coulon, Frédéric; Orsi, Roberto; Turner, Claire; Walton, Chris; Daly, Paddy; Pollard, Simon J T

    2009-02-01

    Coal tars have been identified as posing a threat to human health due to their toxic, mutagenic and carcinogenic characteristics. Workers involved in former gasholders decommissioning are potentially exposed to relevant concentrations of volatile and semi-volatile hydrocarbons upon opening up derelict tanks and during tar excavation/removal. While information on contaminated sites air-quality and its implications on medium-long term exposure is available, acute exposure issues associated with the execution of critical tasks are less understood. Calculations indicated that the concentration of a given contaminant in the gasholder vapour phase only depends on the coal tar composition, being only barely affected by the presence of water in the gasholder and the tar volume/void space ratio. Fugacity modelling suggested that risk-critical compounds such as benzene, naphthalene and other monocyclic and polycyclic aromatic hydrocarbons may gather in the gasholder air phase at significant concentrations. Gasholder emissions were measured on-site and compared with the workplace exposure limits (WELs) currently in use in UK. While levels for most of the toxic compounds were far lower than WELs, benzene air-concentrations where found to be above the accepted threshold. In addition due to the long exposure periods involved in gasholder decommissioning and the significant contribution given by naphthalene to the total coal tar vapour concentration, the adoption of a WEL for naphthalene may need to be considered to support operators in preventing human health risk at the workplace. The Level I fugacity approach used in this study demonstrated its suitability for applications to sealed environments such as gasholders and its further refining could provide a useful tool for land remediation risk assessors.

  6. Contaminant characterization of sediment and pore-water in the Clinch River and Poplar Creek

    International Nuclear Information System (INIS)

    Levine, D.A.; Harris, R.A.; Campbell, K.R.; Hargrove, W.W.; Rash, C.D.

    1995-01-01

    Sediment and pore-water samples were collected from 80 locations in the Clinch River and Poplar Creek system to characterize concentrations and spatial distribution of contaminants for use in ecological risk assessment. Sediment cores were collected at each site and the top 15 cm was analyzed to represent the biologically active zone. Sediment for pore-water extraction was collected in large volumes using a Ponar grab sampler. Pore-water was extracted from this sediment using centrifugation, All samples were analyzed for metals (including methyl mercury), organics, and radiological constituents. Additionally, sediment was analyzed for physical properties: particle size distribution, density, and porosity. Sediment and pore-water were also analyzed for total organic carbon and nitrogen and ammonia levels. Sediment and pore-water were also analyzed for total organic carbon and nitrogen and ammonia levels. Sediment and pre-water results indicate that there are several areas where concentrations of a variety of contaminants are high enough to causes ecological effects. These locations in the river are immediately downstream from know sources of Contamination from on-site DOE facilities. East Fork Poplar Creek is a source of several metals, including mercury, cadmium, chromium, and copper. Mitchell Branch is a source of number of metals, uranium isotopes, technetium-99, and several PAHs. There are two clear sources of arsenic and selenium to the system, one in Poplar Creek and one in Melton Hill Reservoir, both related to past disposal of coal-ash. High concentrations in sediments did not always coincide with high concentrations in pore-water for the same sites and contaminants. This appears to be related to particle size of the sediment and total organic carbon

  7. A Risk-Based Characterization of Sediment Contamination by Legacy and Emergent Contaminants of Concern in Coastal British Columbia, Canada.

    Science.gov (United States)

    Morales-Caselles, Carmen; Desforges, Jean-Pierre W; Dangerfield, Neil; Ross, Peter S

    2017-08-01

    Sediments have long been used to help describe pollution sources, contaminated sites, trends over time, and habitat quality for marine life. We collected surficial sediments from 12 sites at an average seawater depth of 25 m in three near-urban areas of the Salish Sea (British Columbia, Canada) to investigate habitat quality for marine life, including heavily contaminated killer whales. Samples were analyzed using high-resolution instrumentation for a wide variety of congeners of polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs), hexabromocyclododecane (HBCDD), polybrominated biphenyls, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans, organochlorine pesticides, and polychlorinated naphthalenes (PCNs). The top six contaminant classes detected in sediments were ∑PCB > ∑PBDE > ∑PCDD/F > DDT > ∑HBCDD > ∑PCN. Near-urban harbor sediments had up to three orders of magnitude higher concentrations of contaminants than more remote sites. With limited tools available to characterize biological risks associated with complex mixtures in the real world, we applied several available approaches to prioritize the pollutant found in our study: (1) sediment quality guidelines from the Canadian Council of Ministers of the Environment where available; (2) US NOAA effects range low and other international guidelines; (3) total TEQ for dioxin-like PCBs for the protection of mammals; and (4) the calculation of risk quotients. Our findings provide an indication of the state of contamination of coastal environments in British Columbia and guidance for chemical regulations and priority setting, as well as management actions including best-practices, dredging, disposal at sea, and source control. In this regard, the legacy PCB and the emergent PBDEs should command continued priority monitoring.

  8. Supplementary guidance for the investigation and risk-assessment of potentially contaminated sediments

    Energy Technology Data Exchange (ETDEWEB)

    Baker, K.; Spadaro, P.; Starr, J.; Thomas, J. [Arcadis, Arnhem (Netherlands); Hildenbrand, B. [Energy Institute, London (United Kingdom); Smith, J.W.N.; Dunk, M.; Grosjean, T.; De Ibarra, M.; Medve, A.; Den Haan, K.

    2013-11-15

    This report provides guidance on the investigation and assessment of potentially contaminated sediments, focusing on the inland, estuarine and coastal environments. It is designed as a complementary, technical companion document to Energy Institute and CONCAWE (2013) report 'Guidance on characterising, assessing and managing risks associated with potentially contaminated sediments' (Report E1001). It highlights a number of significant challenges associated with assessing the aquatic and water bottom environment, which means that a sediment assessment should not be undertaken lightly. Where a decision is taken to undertake a site assessment, this report promotes the use of an iterative process of Conceptual Site Model (CSM) development, data collection, data evaluation and a continuous CSM refinement, taking into account the results obtained. Risk-based assessment is described throughout the report, entailing four tiers of assessment, which progress from a qualitative assessment (Tier 0) through to a detailed cause-attribution assessment (Tier 3), in which the decrease in uncertainty in the assessment process is balanced against the increased costs and timescales with progress to a higher tier assessment. The application of this evidence-driven risk-based approach to sediment site management, including remedial control measures, should help to overcome at least some of the challenges associated with contaminants in sediment sites in Europe, and promote a sustainable approach to sediment management on a case-by-case basis.

  9. Process of treating tars

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, C; Hempel, H; Weissenburger, H

    1955-05-05

    A process is described for treating tars or tar oils, especially carbonization tars, characterized in that the tars or tar oils are mixed with benzene or light oils which contain no aromatic material or only slight amounts, or with gas oil in such amounts that the asphalt precipitates, and after separation of the precipitated material the mixture is treated with caustic solution for separation of the phenols, and after separation of the phenolate liquor the mixture is subjected to heating for removal of the dilution medium, then the remaining oil can be used as heating oil or it is submitted to distillation for the purpose of recovering a fuel suitable for diesel motors, while the phenolate liquor is worked up into phenols.

  10. INTERACTIONS AMONG PHOSPHATE AMENDMENTS, MICROBES AND URANIUM MOBILITY IN CONTAMINATED SEDIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Knox, A

    2007-08-30

    The use of sequestering agents for the transformation of radionuclides in low concentrations in contaminated soils/sediments offers considerable potential for long-term environmental cleanup. This study evaluated the influence of four phosphate amendments and two microbial amendments on U availability. The synchrotron X-ray fluorescence mapping of the untreated U-contaminated sediment showed that U was closely associated with Mn. All tested phosphate amendments reduced aqueous U concentration more than 90%, likely due to formation of insoluble phosphate precipitates. The addition of A. piechaudii and P. putida alone were found to reduce U concentrations 63% and 31% respectively. Uranium sorption in phosphate treatments was significantly reduced in the presence of microbes. However, increased microbial activity in the treated sediment led to reduction of phosphate effectiveness. The average U concentration in 1 M MgCl{sub 2} extract from U amended sediment was 437 {micro}g/kg, but in the same sediment without microbes (autoclaved sediment), the extractable U concentration was only 103 {micro}g/kg. When the autoclaved amended sediment was treated with autoclaved biological apatite, U concentration in the 1 M MgCl{sub 2} extract was {approx}0 {micro}g/kg. Together these tests suggest that microbes may enhance U leaching and reduce phosphate amendment remedial effectiveness.

  11. Historical record of mercury contamination in sediments from the Babeni Reservoir in the Olt River, Romania.

    Science.gov (United States)

    Bravo, Andrea Garcia; Loizeau, Jean-Luc; Ancey, Lydie; Ungureanu, Viorel Gheorghe; Dominik, Janusz

    2009-08-01

    Mercury (Hg) is a ubiquitous and hazardous contaminant in the aquatic environment showing a strong biomagnification effect along the food chain. The most common transfer path of Hg to humans is contaminated fish consumption. In severely exposed humans, Hg poisoning may lead to damage in the central nervous system. Thus, it is important to examine current and past contamination levels of Hg in aquatic milieu. The Olt River is the largest Romanian tributary of the Danube River. The use of Hg as an electrode in a chlor-alkali plant contributed to the contamination of the aquatic environment in the Rm Valcea region. The purpose of this study was to compare the current state of Hg contamination with the past contamination using a historical record obtained from a dated sediment core from one of the Olt River reservoirs (Babeni) located downstream from the chlor-alkali plant. To our knowledge, no published data on Hg contamination in this region are available. The Babeni Reservoir was selected for this study because it is situated downstream from the chlor-alkali plant, whilst the other reservoirs only retain the pollutants coming from the upstream part of the watershed. Preliminary analyses (unpublished) showed high Hg concentrations in the surface sediment of the Babeni Reservoir. One core was taken in the upstream Valcea Reservoir to provide a local background level of Hg concentrations in sediments. Sediment texture was uniform in the cores from both reservoirs. Laminated sediment structure, without any obvious discontinuities, was observed. Hg concentrations in the sediment core from the Valcea Reservoir were low and constant (0.01-0.08 mg/kg). In Babeni Reservoir sediments, Hg concentrations were very high in the deeper core section (up to 45 mg/kg in the longest core) and decreased to lower concentrations toward the top of the cores (1.3-2.4 mg/kg). This decrease probably reflects technological progress in control of emissions from the Hg-cell-based chlor

  12. Sources and contamination rate of port sediments: evidences from dimensional, mineralogical, and chemical investigations

    Science.gov (United States)

    Lucchetti, Gabriella; Cutroneo, Laura; Carbone, Cristina; Consani, Sirio; Vagge, Greta; Canepa, Giuseppe; Capello, Marco

    2017-04-01

    Ports are complex environments due to their complicated geometry (quays, channels, and piers), the presence of human activities (vessel traffic, yards, industries, and discharges), and natural factors (stream and torrent inputs, sea action, and currents). Due to the many activities that take place in a port, sediments and waters are often contaminated by different kinds of chemicals, such as hydrocarbons, dioxins, pesticides, nutrients, and metals. The contamination rate of a port basin is site specific and depends on the sources of contamination in the nearby urban system as well as the port system itself, such as city discharges and sewers, river intake, vessel traffic, factories (Taylor and Owens, 2009). Moreover, two important sources and vehicles of contaminants are: a) anthropogenic road deposited sediments derived from the runoff of the port and city area, and natural road deposited sediments derived from rivers and torrents, and b) airborne particulate matter and sediments (Taylor and Owens, 2009). The Port of Genoa is situated at the apex of the Ligurian Sea in the north western Mediterranean Sea and is characterised by the presence of several commercial activities that have contributed, over the years, and still contribute today, to the contaminant accumulation in both the water column and the bottom sediments. This port basin includes the mouth of several streams and the mouth of the Bisagno and the Polcevera Torrents, along the banks of which can be found several small towns, quarries, factories, and the suburbs of the city of Genoa, a ferry terminal, different container terminals, marinas, dry docks, the coal power plant of Genoa, and different wastewater treatment plant discharges. Starting from these considerations, we have examined the marine environment of a port from the point of view of the water mass circulation, hydrological characteristics, distribution of the sediment grain size, mineralogical characteristics, and metal concentrations of the

  13. The significance of sediment contamination in the Elbe River floodplain (Czech Republic)

    Science.gov (United States)

    Chalupová, Dagmar; Janský, Bohumír; Langhammer, Jakub; Šobr, Miroslav; Jiři, Medek; Král, Stanislav; Jiřinec, Petr; Kaiglova, Jana; Černý, Michal; Žáček, Miroslav; Leontovyčova, Drahomíra; Halířová, Jarmila

    2015-04-01

    The abstract brings the information about the research that was focused on anthropogenic pollution of river and lake sediments in the middle course of the Elbe River (Czech Republic). The main aim was to identify and to evaluate the significance of old polluted sediments in the river and its side structures (old meanders, cut lakes, oxbow lakes) between Hradec Králové and Mělník (confluence with the Moldau River) and to assess the risk coming from the remobilization of the contaminated matter. The Elbe River floodplain has been highly inhabited since the Middle Ages, and, especially in the 20th century, major industrial plants were founded here. Since that time, the anthropogenic load of the river and it`s floodplain has grown. Although the contaminants bound to the sediment particles are usually stable, the main risk is coming from the fact that under changes in hydrological regime and water quality (floods, changes in pH, redox-potential, presence of complex substances etc.), the pollution can be released and remobilized again. The most endangered areas are: the surroundings of Pardubice (chemical factory Synthesia, Inc.; refinery PARAMO), and Neratovice (chemical factory Spolana, Inc.). The chemical factories situated close to these towns represented the most problematic polluters of the Elbe River especially during 2nd half of 20th century. In the research, the main attention was aimed at subaquatic sediments of selected cut lakes situated in the vicinity of the above mentioned sources of pollution. To describe the outreach of contamination, several further fluvial lakes were taken into account too. Sediment sampling was carried out from boats on lakes and with the help of drilling rig in the floodplain. Gained sediment cores were divided into several parts which were analysed separately. Chemical analyses included substances identified by ICPER (International Commission for the Protection of the Elbe River) as well as chemicals considered as significant in

  14. Polycyclic aromatic hydrocarbon contamination in stormwater detention pond sediments in coastal South Carolina.

    Science.gov (United States)

    Weinstein, John E; Crawford, Kevin D; Garner, Thomas R

    2010-03-01

    The purpose of this study was to characterize the polycyclic aromatic hydrocarbon (PAH) contamination in the sediments of stormwater detention ponds in coastal South Carolina. Levels of the sum of PAH analytes were significantly higher in the sediments of commercial ponds compared to that of reference, golf course, low-density residential, and high-density residential ponds. Isomer ratio analysis suggested that the predominant source of PAHs were pyrogenic; however, many ponds had a PAH signature consistent with mixed uncombusted and combusted PAH sources. PAH levels in these sediments could be modeled using both pond drainage area and pond surface area. These results demonstrate that the sediment from most commercial ponds, and a few residential and golf course ponds, were moderately contaminated with PAHs. PAH levels in these contaminated ponds exceeded between 42% and 75% of the ecological screening values for individual PAH analytes established by US EPA Region IV, suggesting that they may pose a toxicological risk to wildlife.

  15. Mining-Related Sediment and Soil Contamination in a Large Superfund Site: Characterization, Habitat Implications, and Remediation.

    Science.gov (United States)

    Juracek, K E; Drake, K D

    2016-10-01

    Historical mining activity (1850-1970) in the now inactive Tri-State Mining District provided an ongoing source of lead and zinc to the environment including the US Environmental Protection Agency Superfund site located in Cherokee County, southeast Kansas, USA. The resultant contamination adversely affected biota and caused human health problems and risks. Remediation in the Superfund site requires an understanding of the magnitude and extent of contamination. To provide some of the required information, a series of sediment and soil investigations were conducted in and near the Superfund site to characterize lead and zinc contamination in the aquatic and floodplain environments along the main-stem Spring River and its major tributaries. In the Superfund site, the most pronounced lead and zinc contamination, with concentrations that far exceed sediment quality guidelines associated with potential adverse biological effects, was measured for streambed sediments and floodplain soils located within or downstream from the most intensive mining-affected areas. Tributary streambeds and floodplains in affected areas are heavily contaminated with some sites having lead and zinc concentrations that are an order of magnitude (or more) greater than the sediment quality guidelines. For the main-stem Spring River, the streambed is contaminated but the floodplain is mostly uncontaminated. Measured lead and zinc concentrations in streambed sediments, lakebed sediments, and floodplain soils documented a persistence of the post-mining contamination on a decadal timescale. These results provide a basis for the prioritization, development, and implementation of plans to remediate contamination in the affected aquatic and floodplain environments within the Superfund site.

  16. Mining-related sediment and soil contamination in a large Superfund site: Characterization, habitat implications, and remediation

    Science.gov (United States)

    Juracek, Kyle E.; Drake, K. D.

    2016-01-01

    Historical mining activity (1850–1970) in the now inactive Tri-State Mining District provided an ongoing source of lead and zinc to the environment including the US Environmental Protection Agency Superfund site located in Cherokee County, southeast Kansas, USA. The resultant contamination adversely affected biota and caused human health problems and risks. Remediation in the Superfund site requires an understanding of the magnitude and extent of contamination. To provide some of the required information, a series of sediment and soil investigations were conducted in and near the Superfund site to characterize lead and zinc contamination in the aquatic and floodplain environments along the main-stem Spring River and its major tributaries. In the Superfund site, the most pronounced lead and zinc contamination, with concentrations that far exceed sediment quality guidelines associated with potential adverse biological effects, was measured for streambed sediments and floodplain soils located within or downstream from the most intensive mining-affected areas. Tributary streambeds and floodplains in affected areas are heavily contaminated with some sites having lead and zinc concentrations that are an order of magnitude (or more) greater than the sediment quality guidelines. For the main-stem Spring River, the streambed is contaminated but the floodplain is mostly uncontaminated. Measured lead and zinc concentrations in streambed sediments, lakebed sediments, and floodplain soils documented a persistence of the post-mining contamination on a decadal timescale. These results provide a basis for the prioritization, development, and implementation of plans to remediate contamination in the affected aquatic and floodplain environments within the Superfund site.

  17. Combining contamination indexes, sediment quality guidelines and multivariate data analysis for metal pollution assessment in marine sediments of Cienfuegos Bay, Cuba.

    Science.gov (United States)

    Peña-Icart, Mirella; Pereira-Filho, Edenir Rodrigues; Lopes Fialho, Lucimar; Nóbrega, Joaquim A; Alonso-Hernández, Carlos; Bolaños-Alvarez, Yoelvis; Pomares-Alfonso, Mario S

    2017-02-01

    The purpose of the present work was to combine several tools for assessing metal pollution in marine sediments from Cienfuegos Bay. Fourteen surface sediments collected in 2013 were evaluated. Concentrations of As, Cu, Ni, Zn and V decreased respect to those previous reported. The metal contamination was spatially distributed in the north and south parts of the bay. According to the contamination factor (CF) enrichment factor (EF) and index of geoaccumulation (I geo ), Cd and Cu were classified in that order as the most contaminated elements in most sediment. Comparison of the total metal concentrations with the threshold (TELs) and probable (PELs) effect levels in sediment quality guidelines suggested a more worrisome situation for Cu, of which concentrations were occasional associated with adverse biological effects in thirteen sediments, followed by Ni in nine sediments; while adverse effects were rarely associated with Cd. Probably, Cu could be considered as the most dangerous in the whole bay because it was classified in the high contamination levels by all indexes and, simultaneously, associated to occasional adverse effects in most samples. Despite the bioavailability was partially evaluated with the HCl method, the low extraction of Ni (<3% in all samples) and Cu (<55%, except sample 3) and the relative high extraction of Cd (50% or more, except sample 14) could be considered as an attenuating (Ni and Cu) or increasing (Cd) factor in the risk assessment of those element. Copyright © 2016. Published by Elsevier Ltd.

  18. Mapping sediment contamination and toxicity in Winter Quarters Bay, McMurdo Station, Antarctica.

    Science.gov (United States)

    Crockett, Alan B; White, Gregory J

    2003-07-01

    Winter Quarters Bay (WQB) is a small embayment located adjacent to McMurdo Station, the largest research base in Antarctica. The bay is approximately 250 m wide and long, with a maximum depth of 33 m. Historically, trash from the McMurdo Station was piled on the steep shoreline of WQB, doused with fuel and ignited. That practice has ceased, and the adjacent land area has been regraded to cover the residual waste. The bottom of WQB remains littered with drums, equipment, tanks, tires, cables, and other objects, especially the southeastern side of the bay where dumping took place. Sediments are contaminated with PCBs, metals, and hydrocarbon fuels. The objectives of this study were to map the distribution of organic contaminants in WQB, assess the toxicity of WQB sediments using a simple microbial test, and determine correlations between toxicity and contaminant levels. The study suggests that adverse ecological effects have occurred from one or more of the contaminants found in WQB but the source of the toxic impacts to bay sediments remains unknown. Whole sediment toxicity was only correlated with oil-equivalent while solvent extracts of sediments were correlated with PAHs and oil-equivalent. The authors recommend that an integrated research plan be developed that focuses on determining what additional information is needed to make informed decisions on possible remediation of WQB.

  19. Tar removal from biomass gasification streams: processes and catalysts; Remocao do alcatrao de correntes de gaseificacao de biomassa: processos e catalisadores

    Energy Technology Data Exchange (ETDEWEB)

    Quitete, Cristina P.B. [Centro de Pesquisa e Desenvolvimento Leopoldo Americo Miguez de Mello (CENPES/PETROBRAS), Rio de Janeiro, RJ (Brazil). Processos de Conversao de Biomassa; Souza, Mariana M.V.M., E-mail: mmattos@eq.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Centro de Tecnologia. Escola de Quimica

    2014-07-01

    Biomass gasification is a technology that has attracted great interest in synthesis of biofuels and oxo alcohols. However, this gas contains several contaminants, including tar, which need to be removed. Removal of tar is particularly critical because it can lead to operational problems. This review discusses the major pathways to remove tar, with a particular focus on the catalytic steam reforming of tar. Few catalysts have shown promising results; however, long-term studies in the context of real biomass gasification streams are required to realize their potential. (author)

  20. Monitoring of tar contents in gases. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Finn [ChimneyLab Europe ApS, Hadsten (Denmark); Houmann Jakobsen, H. [BioSynergi Proces ApS, Hoersholm (Denmark)

    2012-08-15

    The purpose of this project is to develop and test a relative cheap and simple online tar measuring method, which can monitor the tar content in product gas from thermal gasification. The measuring principle is absorption of tar from sample gas in Isopropanol (IPA), and measuring on this solution by UV-spectrophotometer. Continuous sampling of tar containing producer gas turned out to be a larger problem than earlier foreseen. The best solution was decided to be sampling with higher flows, and afterwards cleaning the IPA in activated carbon. The ambitions for continuous sampling had to be decreased to 1 week, where the IPA and the activated carbon is contaminated by tar and has to be replaced. However this requires larger amounts of IPA and activated carbon. For IPA the weekly consumption was 12-15 Litres and for activated carbon 10 Litres. The whole analyzer unit turned out to be more complex than first projected, mainly because of the increased amounts of IPA. The best mist filter, with respect to pressure drop, efficiency and retention time is a combination of glass wool and quarts wool. The unit has been tested on gas; 20 kW pellets burner for 116 hours. Harbooere updraft gasifier for 519 hours. Skive fluid bed gasifier for 879 hours. There have during the project period been several simple practical problems such as bubbles in the IPA, increasing pressure drop over the activated carbon bed, dropout of UV data acquisition program and increasing baseline. The principle showed from the beginning some good results, with the limitation of 1 week continuous operation, but at the 5. period in Skive the baseline was increasing all the time, and it was not possible to solve this problem. (LN)

  1. Topical tar: Back to the future

    Energy Technology Data Exchange (ETDEWEB)

    Paghdal, K.V.; Schwartz, R.A. [University of Medicine & Dentistry of New Jersey, Newark, NJ (United States)

    2009-08-15

    The use of medicinal tar for dermatologic disorders dates back to the ancient times. Although coal tar is utilized more frequently in modern dermatology, wood tars have also been widely employed. Tar is used mainly in the treatment of chronic stable plaque psoriasis, scalp psoriasis, atopic dermatitis, and seborrheic dermatitis, either alone or in combination therapy with other medications, phototherapy, or both. Many modifications have been made to tar preparations to increase their acceptability, as some dislike its odor, messy application, and staining of clothing. One should consider a tried and true treatment with tar that has led to clearing of lesions and prolonged remission times. Occupational studies have demonstrated the carcinogenicity of tar; however, epidemiologic studies do not confirm similar outcomes when used topically. This article will review the pharmacology, formulations, efficacy, and adverse effects of crude coal tar and other tars in the treatment of selected dermatologic conditions.

  2. Evolution of radioactive dose rates in fresh sediment deposits along coastal rivers draining Fukushima contamination plume.

    Science.gov (United States)

    Evrard, Olivier; Chartin, Caroline; Onda, Yuichi; Patin, Jeremy; Lepage, Hugo; Lefèvre, Irène; Ayrault, Sophie; Ottlé, Catherine; Bonté, Philippe

    2013-10-29

    Measurement of radioactive dose rates in fine sediment that has recently deposited on channel bed-sand provides a solution to address the lack of continuous river monitoring in Fukushima Prefecture after Fukushima Dai-ichi nuclear power plant (FDNPP) accident. We show that coastal rivers of Eastern Fukushima Prefecture were rapidly supplied with sediment contaminated by radionuclides originating from inland mountain ranges, and that this contaminated material was partly exported by typhoons to the coastal plains as soon as by November 2011. This export was amplified during snowmelt and typhoons in 2012. In 2013, contamination levels measured in sediment found in the upper parts of the catchments were almost systematically lower than the ones measured in nearby soils, whereas their contamination was higher in the coastal plains. We thereby suggest that storage of contaminated sediment in reservoirs and in coastal sections of the river channels now represents the most crucial issue.

  3. Links between contaminant hotspots in low flow estuarine systems and altered sediment biogeochemical processes

    Science.gov (United States)

    Sutherland, Michael D.; Dafforn, Katherine A.; Scanes, Peter; Potts, Jaimie; Simpson, Stuart L.; Sim, Vivian X. Y.; Johnston, Emma L.

    2017-11-01

    The urbanisation of coastal zones is a major threat to the health of global estuaries and has been linked to increased contamination (e.g. metals) and excess organic matter. Urban stormwater networks collect and funnel contaminants into waterways at point sources (e.g. stormdrains). Under dry, low flow conditions, these stormwater contaminants can accumulate in sediments over time and result in modifications to benthic sediment biogeochemical processes. To quantify these processes, this field study measured differences in benthic metabolism (CR, GPP, NEM) and sediment-water nutrient fluxes (NH3, NOx, PO4) associated with stormdrains (0 m, 200 m and 1000 m away) and increased water-retention (embayments vs channels). Significant changes to benthic metabolism were detected with distance from stormdrains, and with differences in water-retention rates, above natural spatial and temporal variation. Oxygen consumption was ∼50% higher at stormdrains (0 m) compared to 1000 m away and >70% higher at stormdrains (0 m) located in embayments compared to channels. Oxygen production also appeared to decrease with distance from stormdrains in embayments, but patterns were variable. These changes to benthic metabolism were of a magnitude expected to influence benthic nutrient cycling, but NH3, NOx and PO4 fluxes were generally low, and highly spatially and temporally variable. Overall, metal (Cu) contamination explained most of the variation in sediment biogeochemical processes between embayments and channels, while sediment grain size explained differences in fluxes with distance from stormdrains. Importantly, although there was evidence of increased productivity associated with stormdrains, we also detected evidence of early hypoxia suggesting that systems with legacy stormwater contaminants exist on a tipping point. Future work should investigate changes to sediment processes after a major rainfall event, when large and sudden inputs of potentially toxic contaminants occur

  4. Comparison of contaminants from different trophic levels and ecosystems

    DEFF Research Database (Denmark)

    Dietz, R.; Riget, F.; Cleemann, M.

    2000-01-01

    The present paper provides an overview of the priority contaminants and media from the Greenland part of the Arctic Monitoring and Assessment Program. Levels and accumulation patterns of heavy metals, POPs and a radionuclide (Cs-137) are compared from the terrestrial, freshwater and marine...... ecosystems. Of the nine compounds presented, seven (Cd, Hg, Se, Sigma PCB, Sigma DDT, Sigma HCH, HCB) increased in concentration towards higher trophic levels. For these contaminants the concentrations in soil and aquatic sediment were in the same order of magnitude, whereas the concentrations in marine...

  5. Muddied waters: suspended sediment impacts on gill structure and aerobic scope in an endangered native and an invasive freshwater crayfish

    DEFF Research Database (Denmark)

    Rosewarne, P.J.; Svendsen, Jon Christian; Mortimer, R.J.G.

    2014-01-01

    Suspended sediment (SS) loadings in freshwater habitats have increased over the past century and SS is now a significant environmental stressor. Greater tolerance to environmental stressors has been proposed as a factor in the success of aquatic invasive species. Further, parasites may interact...

  6. Removing tar information from cigarette packages may reduce South Korean smokers' misconceptions about low-tar cigarettes

    Directory of Open Access Journals (Sweden)

    Hye-Jin Paek

    2018-03-01

    Full Text Available Background Many smokers still have misconceptions about “light” or “low tar” cigarettes. In South Korea, low-tar (< 3 mg cigarette sales have increased sharply from 1.8% in 2002 to 49.2% in 2015. Although government regulations forbid cigarette packages from displaying messages such as “mild,” “low-tar,” and “light,” numbers indicating tar amounts are still permitted. This study examines whether removing tar information from packaging altogether reduces people's misconceptions about low tar cigarettes. Methods An online experiment was conducted among 531 smokers who were randomly assigned to one of two conditions. In the “tar” condition, 271 participants were shown in random order three cigarette packages for three major brands (Esse, The One, Marlboro with different tar amounts. In the “no-tar” condition, 260 participants were shown the same packages without tar information. Next, participants evaluated which type of cigarette was mildest, least harmful, easier for nonsmokers to start smoking, and easier for smokers to quit. After descriptive statistics were checked, twelve sets of chi-square tests were performed. Results Average age of the participants was 26.22 (14 - 62 years; 53.5% were male. All 12 chi-square tests were statistically significant. Participants in the tar condition judged the lowest-tar cigarette to be mildest, least harmful, easier to start, and easier to quit. In the no-tar condition, for the Korean brands Esse and The One, most respondents evaluated all cigarette types to be the same only for harm, ease of starting, and ease of quitting; for Marlboro, judgments were the same as those in the tar condition except that “easier to quit” was judged to be the same across the three types. Conclusions Banning tar information from cigarette packages may help reduce smokers' misconceptions about low-tar cigarettes. People have inconsistent judgments about differently packaged cigarettes when tar

  7. Quality controlled water, sediment, tissue, and tar/oil chemistry analyses from the Deepwater Horizon (DWH) oil spill event in the Gulf of Mexico from 2010-04 to 2011-06, sourced from NOAA's Query Manager data management system (NODC Accession 0108924)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This collection includes 4 data files (one each for water, sediment, tissue, and tar/oil analyses) containing data from the Deepwater Horizon (DWH) Oil Spill Event...

  8. Biodegradation studies of diesel-contaminated soils and sediments

    International Nuclear Information System (INIS)

    Schlauch, M.; Clark, D.

    1992-01-01

    Radian Corporation is currently remediating the Atchison, Topeka and Sante Fe Railway Superfund site in Clovis, New Mexico. Biodegradation of the petroleum hydrocarbon-contaminated soils and sediments was chosen as the remedial alternative. In order to evaluate the optimum conditions for full-scale bioremediation at this site, Radian designed and implemented various laboratory and field studies. The initial laboratory treatability study was conducted to determine if hydrocarbons in both soils and sediments could be biodegraded using indigenous microorganisms, and determine that the soil were biodegradable, while the sediments were not due to inhibitory factors. To further evaluate the biodegradability6 of the sediments, a laboratory study was initiated which introduced chloride-resistant microbes. The study showed that the sediment bioremediation was possibly by utilizing these microbes; however, the cost was not favorable. Finally, a field plot study was initiated to determine how soil biodegradation would proceed in field conditions, to optimize influencing factors such as moisture and nutrient levels and bioseed addition, and to investigate alternate methods of bioremediating the sediments. Results showed that hydrocarbons in the soils biodegraded much faster in the field than in the lab, and that hydrocarbons in sediments applied to biotreated soils containing acclimated microorganisms were successfully biodegraded

  9. Assessment of metal and trace element contamination in water, sediment, plants, macroinvertebrates, and fish in Tavasci Marsh, Tuzigoot National Monument, Arizona

    Science.gov (United States)

    Beisner, Kimberly R.; Paretti, Nicholas V.; Brasher, Anne M.D.; Fuller, Christopher C.; Miller, Matthew P.

    2014-01-01

    Tavasci Marsh is a large freshwater marsh within the Tuzigoot National Monument in central Arizona. It is the largest freshwater marsh in Arizona that is unconnected to the Colorado River and is designated as an Important Bird Area by the Audubon Society. The marsh has been altered significantly by previous land use and the monument’s managers are evaluating the restoration of the marsh. In light of historical mining activities located near the marsh from the first half of the 20th century, evaluations of water, sediment, plant, and aquatic biota in the marsh were conducted. The evaluations were focused on nine metals and trace elements commonly associated with mining and other anthropogenic activities (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn) together with isotopic analyses to understand the presence, sources and timing of water and sediment contaminants to the marsh and the occurrence in aquatic plants, dragonfly larvae, and fish. Results of water analyses indicate that there were two distinct sources of water contributing to the marsh during the study: one from older high elevation recharge entering the marsh at Shea Spring (as well as a number of unnamed seeps and springs on the northeastern edge of the marsh) and the other from younger low elevation recharge or from Pecks Lake. Water concentrations for arsenic exceeded the U.S. Environmental Protection Agency primary drinking water standard of 10 μg/L at all sampling sites. Surface waters at Tavasci Marsh may contain conditions favorable for methylmercury production. All surficial and core sediment samples exceeded or were within sample concentration variability of at least one threshold sediment quality guideline for As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn. Several sediment sites were also above or were within sample concentration variability of severe or probable effect sediment quality guidelines for As, Cd, and Cu. Three sediment cores collected in the marsh have greater metal and trace element concentrations

  10. Sedimentation and contamination patterns of dike systems along the Rhône River (France)

    Science.gov (United States)

    Seignemartin, Gabrielle; Tena, Alvaro; Piégay, Hervé; Roux, Gwenaelle; Winiarski, Thierry

    2017-04-01

    Humans have historically modified the Rhône River, especially in the last centuries. In the 19th century, the river was systematically embanked for flood protection purposes, and works continued along the 20th century with dike system engineering work for navigation. The Rhône was canalised and its historical course by-passed by a series of hydroelectric dams. Besides, industrial activity polluted the river. For example, high levels of PCB's were attributed to the inputs of the heavily industrialized zone downstream from Lyon. During floods, these contaminants, associated with the suspended sediment, were trapped by the engineering works and the floodplain. Currently, a master plan to reactivate the river dynamics in the alluvial margins by removing the groyne-fields and dikes in the by-passed sections is being implemented. Within this context, this work aims to assess historical dynamics of sediment and associated contaminants in the floodplain (e.g. trace metal elements), notably in the dike system, in order to evaluate the contamination risk related to bank protection removal. With this objective, a transversal methodology has been applied coupling GIS diachronic analysis (old maps, bathymetric data, Orthophotos, LIDAR, etc.) to understand the historical floodplain evolution, sediment survey to obtain sediment thickness (metal rod and Ground Penetrating Radar), and sediment sampling (manual auger and core sampling) to obtain the metal element concentrations (X-Ray Fluorescence and Inductively Coupled Plasma Mass Spectrometry). By this way, metal element patterns were defined and used as contamination tracing indicators to apprehend the contamination history but also as geochemical background indicators to define the sediment source influence. We found that sediment temporal patterns are directly related with the by-pass construction year. Spatially, fine sediment deposition predominates in the dike systems, being lower in the floodplain already disconnected in

  11. Capabilities of Seven Species of Aquatic Macrophytes for Phytoremediation of Pentachlorophenol Contaminated Sediment

    Science.gov (United States)

    Zhao, Liangyuan; Guo, Weijie; Li, Qingyun; Li, Huan; Zhao, Weihua; Cao, Xiaohuan

    2017-01-01

    Sediments are regarded as the ultimate sink of pentachlorophenol(PCP) in aquatic environment, and capabilities of seven species of aquatic macrophytes for remediating PCP contaminated sediment were investigated. Seven species of aquatic macrophytes could significantly accelerate the degradation of PCP in sediments. Among all, canna indica L., Acorus calamus L. and Iris tectorum Maxim. can be used as efficient alternative plants for remediation of PCP contaminated sediment, which attained 98%, 92% and 88% of PCP removal in sediments, respectively. PCP was detected only in root tissues and the uptake was closely related to the root lipid contents of seven plants. The presence of seven aquatic macrophytes significantly increased microbial populations and the activities of dehydrogenase compared with control sediments, indicating that rhizosphere microorganism played important role in the remediation process. In conclusion, seven species of aquatic macrophytes may act as promising tools for the PCP phytoremediation in aquatic environment, especially Canna indica L., Acorus calamus L. and Iris tectorum Maxim.

  12. High bacterial biodiversity increases degradation performance of hydrocarbons during bioremediation of contaminated harbor marine sediments

    International Nuclear Information System (INIS)

    Dell'Anno, Antonio; Beolchini, Francesca; Rocchetti, Laura; Luna, Gian Marco; Danovaro, Roberto

    2012-01-01

    We investigated changes of bacterial abundance and biodiversity during bioremediation experiments carried out on oxic and anoxic marine harbor sediments contaminated with hydrocarbons. Oxic sediments, supplied with inorganic nutrients, were incubated in aerobic conditions at 20 °C and 35 °C for 30 days, whereas anoxic sediments, amended with organic substrates, were incubated in anaerobic conditions at the same temperatures for 60 days. Results reported here indicate that temperature exerted the main effect on bacterial abundance, diversity and assemblage composition. At higher temperature bacterial diversity and evenness increased significantly in aerobic conditions, whilst decreased in anaerobic conditions. In both aerobic and anaerobic conditions, biodegradation efficiencies of hydrocarbons were significantly and positively related with bacterial richness and evenness. Overall results presented here suggest that bioremediation strategies, which can sustain high levels of bacterial diversity rather than the selection of specific taxa, may significantly increase the efficiency of hydrocarbon degradation in contaminated marine sediments. - Highlights: ► Bioremediation performance was investigated on hydrocarbon contaminated sediments. ► Major changes in bacterial diversity and assemblage composition were observed. ► Temperature exerted the major effect on bacterial assemblages. ► High bacterial diversity increased significantly biodegradation performance. ► This should be considered for sediment remediation by bio-treatments. - Bioremediation strategies which can sustain high levels of bacterial diversity may significantly increase the biodegradation of hydrocarbons in contaminated marine sediments.

  13. Distilling tar; distillation, destructive

    Energy Technology Data Exchange (ETDEWEB)

    Brash, P; Young, W

    1866-09-17

    The tarry residue, which separates on treating crude shale oil with sulfuric acid, is redistilled, in the manner described in Specification No. 1278, A.D. 1866, together with shale. Previous to the distillation, the acid is neutralized with lime, or may be separated by blowing steam into the tar and adding salt. The purified tar thus obtained is absorbed by ashes, or is mixed with lime or other alkaline matter, or the shale may be mixed with lime and distilled with the tar, which is allowed to flow over and through the shale during the process. The tar obtained in the purification of natural paraffin may be similarly utilized.

  14. Trace contaminant concentration affects mineral transformation and pollutant fate in hydroxide-weathered Hanford sediments

    International Nuclear Information System (INIS)

    Perdrial, Nicolas; Rivera, Nelson; Thompson, Aaron; O’Day, Peggy A.; Chorover, Jon

    2011-01-01

    Highlights: ► Fate of Sr, Cs and I tracked during hydroxide-weathering of sediments. ► pCO 2 and contaminant concentration affected mineral transformation. ► Sodalite/cancrinite formed at μM levels, chabazite at mM levels. ► Absence of CO 2 resulted in calcite dissolution and strätlingite formation. ► Trace contaminant concentrations modified their own sequestration path. - Abstract: Prior work has shown that when silicaceous sediments are infused with caustic radioactive waste, contaminant fate is tightly coupled to ensuing mineral weathering reactions. However, the effects of local aqueous geochemical conditions on these reactions are poorly studied. Thus, we varied contaminant concentration and pCO 2 during the weathering of previously uncontaminated Hanford sediments over 6 months and 1 year in a solution of caustic waste (pH 13, high ionic strength). Co-contaminants Sr, Cs and I were added at “low” (Cs/Sr: 10 −5 m; I: 10 −7 m) and “high” (Cs/Sr: 10 −3 m; I: 10 −5 m) concentrations, and headspace was held at atmospheric or undetectable ( 2 partial pressure. Solid phase characterization revealed the formation of the zeolite chabazite in “high” samples, whereas feldspathoids, sodalite and cancrinite, were formed preferentially in “low” samples. Sr, Cs and I were sequestered in all reacted sediments. Native calcite dissolution in the CO 2 -free treatment drove the formation of strätlingite (Ca 2 Al 2 SiO 7 ·8H 2 O) and diminished availability of Si and Al for feldspathoid formation. Results indicate that pCO 2 and contaminant concentrations strongly affect contaminant speciation in waste-weathered sediments, and are therefore likely to impact reaction product stability under any remediation scenario.

  15. Toxicity of coal-tar and asphalt sealants to eastern newts, Notophthalmus viridescens

    Energy Technology Data Exchange (ETDEWEB)

    Bommarito, T.; Sparling, D.W.; Halbrook, R.S. [South Illinois University, Carbondale, IL (United States). Cooperative Wildlife Research Laboratory

    2010-09-15

    Between 1970 and 2000 the concentration of total polycyclic aromatic hydrocarbons (TPAH) in several lakes across the country increased whereas those of other persistent organic pollutants (POPs) tended to remain stable or declined. Urbanized watersheds experienced greater rises in TPAH concentration compared to non-urban lakes. Sources for urban PAHs include industrial wastes, vehicular exhausts and oil leaks and sealants from pavement surfaces. Both coal-tar and asphalt sealants are used to protect surfaces but runoff from surfaces coated with coal-tar can have mean concentrations of 3500 mg TPAHs kg{sup -1}, much higher than runoff from asphalt-sealed or cement surfaces. Unaltered parent compounds of PAHs can have many lethal and sublethal toxic effects, but oxidation and UV radiation can alter the toxicity of these compounds, sometimes creating degradates that are many times more toxic than parent compounds. The purposes of this study were to determine if coal-tar sealants can be toxic to adult eastern newts (Notophthalmus viridescens) and to compare the toxicity of coal-tar sealant to that of asphalt sealant. Newts were exposed to sediments containing dried sealants ranging from 0 mg kg{sup -1} to 1500 mg kg{sup -1} under simultaneous exposure to UV radiation and visible light to determine concentration/response relationships. No significant mortality occurred with any treatment. Significant effects due to sealants included decreased righting ability and diminished liver enzyme activities. Coal-tar sealant was more effective in inducing these changes than was asphalt sealant.

  16. Prioritizing research for trace pollutants and emerging contaminants in the freshwater environment

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Kyle E., E-mail: Kyle.Murray@utsa.ed [Center for Water Research, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249-0663 (United States); Thomas, Sheeba M [San Antonio River Authority, San Antonio, TX (United States); Bodour, Adria A [Air Force Center for Engineering and the Environment (AFCEE), Brooks City-Base, TX (United States)

    2010-12-15

    Organic chemicals have been detected at trace concentrations in the freshwater environment for decades. Though the term trace pollutant indicates low concentrations normally in the nanogram or microgram per liter range, many of these pollutants can exceed an acceptable daily intake (ADI) for humans. Trace pollutants referred to as emerging contaminants (ECs) have recently been detected in the freshwater environment and may have adverse human health effects. Analytical techniques continue to improve; therefore, the number and frequency of detections of ECs are increasing. It is difficult for regulators to restrict use of pollutants that are a human health hazard; scientists to improve treatment techniques for higher priority pollutants; and the public to modify consumption patterns due to the vast number of ECs and the breadth of literature on the occurrence, use, and toxicity. Hence, this paper examines literature containing occurrence and toxicity data for three broad classes of trace pollutants and ECs (industrials, pesticides, and pharmaceuticals and personal care products (PPCPs)), and assesses the relevance of 71 individual compounds. The evaluation indicates that widely used industrials (BPF) and PPCPs (AHTN, HHCB, ibuprofen, and estriol) occur frequently in samples from the freshwater environment but toxicity data were not available; thus, it is important to establish their ADI. Other widely used industrials (BDE-47, BDE-99) and pesticides (benomyl, carbendazim, aldrin, endrin, ethion, malathion, biphenthrin, and cypermethrin) have established ADI values but occurrence in the freshwater environment was not well documented. The highest priority pollutants for regulation and treatment should include industrials (PFOA, PFOS and DEHP), pesticides (diazinon, methoxychlor, and dieldrin), and PPCPs (EE2, carbamazepine, {beta}E2, DEET, triclosan, acetaminophen, and E1) because they occur frequently in the freshwater environment and pose a human health hazard at

  17. Prioritizing research for trace pollutants and emerging contaminants in the freshwater environment

    International Nuclear Information System (INIS)

    Murray, Kyle E.; Thomas, Sheeba M.; Bodour, Adria A.

    2010-01-01

    Organic chemicals have been detected at trace concentrations in the freshwater environment for decades. Though the term trace pollutant indicates low concentrations normally in the nanogram or microgram per liter range, many of these pollutants can exceed an acceptable daily intake (ADI) for humans. Trace pollutants referred to as emerging contaminants (ECs) have recently been detected in the freshwater environment and may have adverse human health effects. Analytical techniques continue to improve; therefore, the number and frequency of detections of ECs are increasing. It is difficult for regulators to restrict use of pollutants that are a human health hazard; scientists to improve treatment techniques for higher priority pollutants; and the public to modify consumption patterns due to the vast number of ECs and the breadth of literature on the occurrence, use, and toxicity. Hence, this paper examines literature containing occurrence and toxicity data for three broad classes of trace pollutants and ECs (industrials, pesticides, and pharmaceuticals and personal care products (PPCPs)), and assesses the relevance of 71 individual compounds. The evaluation indicates that widely used industrials (BPF) and PPCPs (AHTN, HHCB, ibuprofen, and estriol) occur frequently in samples from the freshwater environment but toxicity data were not available; thus, it is important to establish their ADI. Other widely used industrials (BDE-47, BDE-99) and pesticides (benomyl, carbendazim, aldrin, endrin, ethion, malathion, biphenthrin, and cypermethrin) have established ADI values but occurrence in the freshwater environment was not well documented. The highest priority pollutants for regulation and treatment should include industrials (PFOA, PFOS and DEHP), pesticides (diazinon, methoxychlor, and dieldrin), and PPCPs (EE2, carbamazepine, βE2, DEET, triclosan, acetaminophen, and E1) because they occur frequently in the freshwater environment and pose a human health hazard at

  18. EVALUATION OF BIOAEROSOL COMPONENTS, GENERATION FACTORS, AND AIRBORNE TRANSPORT ASSOCIATED WITH LIME TREATMENT OF CONTAMINATED SEDIMENT

    Science.gov (United States)

    Lime treatment has been used in contaminated sediment management activities for many purposes such as dewatering, improvement of physical properties, and reducing contaminant mobility. Exothermic volatilization of volatile organic compounds from lime-treated sediment is well kno...

  19. Heavy metal contamination in surface runoff sediments of the urban area of Vilnius, Lithuania

    Directory of Open Access Journals (Sweden)

    Gytautas Ignatavičius

    2017-02-01

    Full Text Available Surface runoff from urbanized territories carries a wide range of pollutants. Sediments in untreated runoff from direct discharge stormwater systems significantly contribute to urban waterway pollution. In this study, heavy metal (Pb, Zn, Cu, Cr, Ba, As and Fe contamination in surface runoff sediments of the urban area of the city of Vilnius was investigated. The surface runoff sediment samples were collected from seven dischargers with the highest volume rate of water flow and concentrations of suspended solids. The geospatial analysis of the distribution of heavy metals shows that there are several active pollution sources supplying the dischargers with contaminated sediments. Most of these areas are located in the central part of the city and in old town with intense traffic. Principal components analysis and t-test results clearly depicted the significantly different chemical compositions of winter and autumn surface sediment samples. The sampling approach and assessment of results provide a useful tool to examine the contamination that is generated in urban areas, distinguish pollution sources and give a better understanding of the importance of permeable surfaces and green areas.

  20. Influence Of Groundwater Discharge On Arsenic Contamination In Sediments

    Science.gov (United States)

    A field investigation was conducted to evaluate the impact of a discharging arsenic plume on sediment contaminant characteristics at a site adjacent to a landfill in northeastern Massachusetts. Site characterization included assessment of the hydrologic and chemical samples coll...

  1. Mineral transformation controls speciation and pore-fluid transmission of contaminants in waste-weathered Hanford sediments

    Science.gov (United States)

    Perdrial, Nicolas; Thompson, Aaron; O'Day, Peggy A.; Steefel, Carl I.; Chorover, Jon

    2014-09-01

    Portions of the Hanford Site (WA, USA) vadose zone were subjected to weathering by caustic solutions during documented releases of high level radioactive waste (containing Sr, Cs and I) from leaking underground storage tanks. Previous studies have shown that waste-sediment interactions can promote variable incorporation of contaminants into neo-formed mineral products (including feldspathoids and zeolites), but processes regulating the subsequent contaminant release from these phases into infiltrating background pore waters remain poorly known. In this paper, reactive transport experiments were conducted with Hanford sediments previously weathered for one year in simulated hyper-alkaline waste solutions containing high or low 88Sr, 127I, and 133Cs concentrations, with or without CO2(aq). These waste-weathered sediments were leached in flow-through column experiments with simulated background pore water (characteristic of meteoric recharge) to measure contaminant release from solids formed during waste-sediment interaction. Contaminant sorption-desorption kinetics and mineral transformation reactions were both monitored using continuous-flow and wet-dry cycling regimes for ca. 300 pore volumes. Less than 20% of contaminant 133Cs and 88Sr mass and less than 40% 127I mass were released over the course of the experiment. To elucidate molecular processes limiting contaminant release, reacted sediments were studied with micro- (TEM and XRD) and molecular- (Sr K-edge EXAFS) scale methods. Contaminant dynamics in column experiments were principally controlled by rapid dissolution of labile solids and competitive exchange reactions. In initially feldspathoidic systems, time-dependent changes in the local zeolitic bonding environment observed with X-ray diffraction and EXAFS are responsible for limiting contaminant release. Linear combination fits and shell-by-shell analysis of Sr K-edge EXAFS data revealed modification in Sr-Si/Al distances within the zeolite cage. Wet

  2. A Field Study of NMR Logging to Quantify Petroleum Contamination in Subsurface Sediments

    Science.gov (United States)

    Fay, E. L.; Knight, R. J.; Grunewald, E. D.

    2016-12-01

    Nuclear magnetic resonance (NMR) measurements are directly sensitive to hydrogen-bearing fluids including water and petroleum products. NMR logging tools can be used to detect and quantify petroleum hydrocarbon contamination in the sediments surrounding a well or borehole. An advantage of the NMR method is that data can be collected in both cased and uncased holes. In order to estimate the volume of in-situ hydrocarbon, there must be sufficient contrast between either the relaxation times (T2) or the diffusion coefficients (D) of water and the contaminant. In a field study conducted in Pine Ridge, South Dakota, NMR logging measurements were used to investigate an area of hydrocarbon contamination from leaking underground storage tanks. A contaminant sample recovered from a monitoring well at the site was found to be consistent with a mixture of gasoline and diesel fuel. NMR measurements were collected in two PVC-cased monitoring wells; D and T2 measurements were used together to detect and quantify contaminant in the sediments above and below the water table at both of the wells. While the contrast in D between the fluids was found to be inadequate for fluid typing, the T2 contrast between the contaminant and water in silt enabled the estimation of the water and contaminant volumes. This study shows that NMR logging can be used to detect and quantify in-situ contamination, but also highlights the importance of sediment and contaminant properties that lead to a sufficiently large contrast in T2 or D.

  3. Dissolved organic matter from soils contaminated by coal tars: towards a better understanding of its nature and reactivity

    International Nuclear Information System (INIS)

    Hanser, Ogier

    2015-01-01

    A large amount of wastelands inherited from former industrial activities contains persistent organic contamination (coal, coal tar...). While the regulation requires an evaluation of the contamination degree of these soils, it doesn't take into account the transformation byproducts such as polar compounds, poorly studied. Yet they solubilize in aqueous phase by percolation of meteoric waters through these contaminated sites. Despite the fact that literature targeting the fresh DOM is abundant, it is not directly transposable to the anthropogenic DOM coming from wastelands, which still need to be more precisely defined to improve our knowledge of this specific DOM and its evolution over time. A multi-technical approach was developed to comprehend the anthropogenic DOM coming from former coking and gas plant soils, thanks to a combination of laboratory experiments (under controlled conditions) and on field devices (lysimeters). Their study show that they contained a high aromatic DOM, while the aromatic polycyclic compounds only consist of a low proportion of the total DOM. Complementary experiences targeting the influence of some parameters (pH, hydrophobicity) suggest a strong link between the pH and the spatial DOM organization and a decrease in the apparent molecular weight with the hydrophobicity. Artificial aging experiences show an enrichment in polar condensed compounds leading to their water mobilization. (author) [fr

  4. 15N indicates an active N-cycling microbial community in low carbon, freshwater sediments.

    Science.gov (United States)

    Sheik, C.

    2017-12-01

    Earth's large lakes are unique aquatic ecosystems, but we know little of the microbial life driving sedimentary biogeochemical cycles and ultimately the isotopic record. In several of these large lakes, water column productivity is constrained by element limitation, such as phosphorus and iron, creating oligotrophic water column conditions that drive low organic matter content in sediments. Yet, these sediments are biogeochemically active and have been shown to have oxygen consumption rates akin to pelagic ocean sediments and complex sulfur cycling dynamics. Thus, large oligotrophic lakes provide unique and interesting biogeochemical contrast to highly productive freshwater and coastal marine systems. Using Lake Superior as our study site, we found microbial community structure followed patterns in bulk sediment carbon and nitrogen concentrations. These observed patterns were loosely driven by land proximity, as some stations are more coastal and have higher rates of sedimentation, allochthonous carbon inputs and productivity than pelagic sites. Interestingly, upper sediment carbon and nitrogen stable isotopes were quite different from water column. Sediment carbon and nitrogen isotopes correlated significantly with microbial community structure. However, 15N showed much stronger correlation than 13C, and became heavier with core depth. Coinciding with the increase in 15N values, we see evidence of both denitrification and anammox processes in 16S rRNA gene libraries and metagenome assembled genomes. Given that microorganisms prefer light isotopes and that these N-cycling processes both contribute to N2 production and efflux from the sediment, the increase in 15N with sediment depth suggests microbial turnover. Abundance of these genomes also varies with depth suggesting these novel microorganisms are partitioning into specific sediment geochemical zones. Additionally, several of these genomes contain genes involved in sulphur cycling, suggesting a dual

  5. Vertical and horizontal distribution of sediment nitrite-dependent methane-oxidizing organisms in a mesotrophic freshwater reservoir.

    Science.gov (United States)

    Long, Yan; Liu, Changbao; Lin, Hengliang; Li, Ningning; Guo, Qingwei; Xie, Shuguang

    2017-06-01

    In the present study, we investigated the spatial change of sediment nitrite-dependent anaerobic methane-oxidizing (n-damo) organisms in the mesotrophic freshwater Gaozhou Reservoir (6 different sampling locations and 2 sediment depths (0-5 cm, 5-10 cm)), one of the largest drinking water reservoirs in China. The abundance of sediment n-damo bacteria was quantified using quantitative polymerase chain reaction assay, while the richness, diversity, and composition of n-damo pmoA gene sequences were characterized using clone library analysis. Vertical and horizontal changes in sediment n-damo bacterial abundance occurred in Gaozhou Reservoir, with 1.37 × 10 5 to 8.24 × 10 5 n-damo 16S rRNA gene copies per gram of dry sediment. Considerable horizontal and vertical variations of n-damo pmoA gene diversity (Shannon index = 0.32-2.50) and composition also occurred in this reservoir. Various types of sediment n-damo pmoA genes existed in Gaozhou Reservoir. A small proportion of n-damo pmoA gene sequences (19.1%) were related to those recovered from "Candidatus Methylomirabilis oxyfera". Our results suggested that sediment n-damo pmoA gene diversity might be regulated by nitrite, while n-damo pmoA gene richness might be governed by multiple environmental factors, including total organic carbon, total phosphorus, nitrite, and total nitrogen.

  6. SEDIMENT CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX.

    Science.gov (United States)

    The increasing density of golf courses represents a potential source of sediment contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to determine the concentrations of contaminants and toxicities...

  7. Geochemical and mineralogical investigation of uranium in multi-element contaminated, organic-rich subsurface sediment

    International Nuclear Information System (INIS)

    Qafoku, Nikolla P.; Gartman, Brandy N.; Kukkadapu, Ravi K.; Arey, Bruce W.; Williams, Kenneth H.; Mouser, Paula J.; Heald, Steve M.; Bargar, John R.; Janot, Noémie; Yabusaki, Steve; Long, Philip E.

    2014-01-01

    Highlights: • Subsurface naturally reduced zones (NRZ) contain U and other potential co-contaminants. • The NRZ has a remarkable assortment of chemically complex, potential U hosts. • Micron-scale, multi-contaminant areas were discovered in NRZ. • U(IV) occurs as biogenic UO 2 (82%), or biomass – bound monomeric U(IV) (18%). • NRZs may exhibit contaminant sink-source complex behavior. - Abstract: Subsurface regions of alluvial sediments characterized by an abundance of refractory or lignitic organic carbon compounds and reduced Fe and S bearing minerals, which are referred to as naturally reduced zones (NRZ), are present at the Integrated Field Research Challenge site in Rifle, CO (a former U mill site), and other contaminated subsurface sites. A study was conducted to demonstrate that the NRZ contains a variety of contaminants and unique minerals and potential contaminant hosts, investigate micron-scale spatial association of U with other co-contaminants, and determine solid phase-bounded U valence state and phase identity. The NRZ sediment had significant solid phase concentrations of U and other co-contaminants suggesting competing sorption reactions and complex temporal variations in dissolved contaminant concentrations in response to transient redox conditions, compared to single contaminant systems. The NRZ sediment had a remarkable assortment of potential contaminant hosts, such as Fe oxides, siderite, Fe(II) bearing clays, rare solids such as ZnS framboids and CuSe, and, potentially, chemically complex sulfides. Micron-scale inspections of the solid phase showed that U was spatially associated with other co-contaminants. High concentration, multi-contaminant, micron size (ca. 5–30 μm) areas of mainly U(IV) (53–100%) which occurred as biogenic UO 2 (82%), or biomass – bound monomeric U(IV) (18%), were discovered within the sediment matrix confirming that biotically induced reduction and subsequent sequestration of contaminant U(VI) via

  8. Wastewater canal Vojlovica, industrial complex Pančevo, Serbia – preliminary ecotoxicological assessment of contaminated sediment

    Directory of Open Access Journals (Sweden)

    IVANA PLANOJEVIĆ

    2011-03-01

    Full Text Available Effluents collected from the industrial complex of Pančevo, Serbia (oil refinery, petrochemical plant, and fertilizer factory, are discharged into a wastewater canal entering the Danube River. In this study, which was focused on sediment assessment, a complex triad approach consisting of chemical analysis, sediment toxicity tests and macrozoobenthos community analysis was applied. In toxicity tests on sediment elutriates, the following responses were registered – stimulatory effect in algal bioassay, no effect in acute test with Daphnia magna, and low to moderate toxicity in the conventional Vibrio fischeri test. Moderate to high toxicities were recorded in solid phase tests on Myriophyllum aquaticum and V. fischeri. High content of Hg, certain PAHs and non-characterised sediment contaminants accumulated over years contribute not only to the registered toxicity, but also to the complete absence of macrozoobenthos. The obtained results proved that regularly measured conventional and priority pollutants are hardly ever the only toxic contaminants present in sediments. Toxicity tests, in particular the contact test, might guide towards a better selection of parameters to be regularly or occasionally monitored. In addition, complete sediment toxicity tests proved to be an appropriate method for assessing the bioavailability of the chemically detected contaminants. The analysis of the macrozoobenthos composition and structure as inevitable part of sediment risk assessment procedures integrates the effects of multiple stressors and gives a realistic insight into not only sediment contamination by toxic pollutants, but also the sediment status in general.

  9. Contaminants in stream sediments from seven United States metropolitan areas: part II—sediment toxicity to the amphipod Hyalella azteca and the midge Chironomus dilutus

    Science.gov (United States)

    Kemble, Nile E.; Hardesty, Douglas K.; Ingersoll, Christopher G.; Kunz, James L.; Sibley, Paul K.; Calhoun, Daniel L.; Gilliom, Robert J.; Kuivila, Kathryn; Nowell, Lisa H.; Moran, Patrick W.

    2013-01-01

    Relationships between sediment toxicity and sediment chemistry were evaluated for 98 samples collected from seven metropolitan study areas across the United States. Sediment-toxicity tests were conducted with the amphipod Hyalella azteca (28 day exposures) and with the midge Chironomus dilutus (10 day exposures). Overall, 33 % of the samples were toxic to amphipods and 12 % of the samples were toxic to midge based on comparisons with reference conditions within each study area. Significant correlations were observed between toxicity end points and sediment concentrations of trace elements, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), or organochlorine (OC) pesticides; however, these correlations were typically weak, and contaminant concentrations were usually below sediment-toxicity thresholds. Concentrations of the pyrethroid bifenthrin exceeded an estimated threshold of 0.49 ng/g (at 1 % total organic carbon) in 14 % of the samples. Of the samples that exceeded this bifenthrin toxicity threshold, 79 % were toxic to amphipods compared with 25 % toxicity for the samples below this threshold. Application of mean probable effect concentration quotients (PECQs) based on measures of groups of contaminants (trace elements, total PAHs, total PCBs,OCpesticides, and pyrethroid pesticides [bifenthrin in particular]) improved the correct classification of samples as toxic or not toxic to amphipods compared with measures of individual groups of contaminants. Sediments are a repository for many contaminants released into surface waters. Because of this, organisms inhabiting sediments may be exposed to a wide range of contaminants (United States Environmental Protection Agency (USEPA) United States Environmental Protection Agency 2000; American Society for Testing and Materials [ASTM] American Society for Testing and Materials International 2012). Contaminants of potential concern in sediments typically include trace elements (metals

  10. Thallium dispersal and contamination in surface sediments from South China and its source identification.

    Science.gov (United States)

    Liu, Juan; Wang, Jin; Chen, Yongheng; Shen, Chuan-Chou; Jiang, Xiuyang; Xie, Xiaofan; Chen, Diyun; Lippold, Holger; Wang, Chunlin

    2016-06-01

    Thallium (Tl) is a non-essential element in humans and it is considered to be highly toxic. In this study, the contents, sources, and dispersal of Tl were investigated in surface sediments from a riverine system (the western Pearl River Basin, China), whose catchment has been contaminated by mining and roasting of Tl-bearing pyrite ores. The isotopic composition of Pb and total contents of Tl and other relevant metals (Pb, Zn, Cd, Co, and Ni) were measured in the pyrite ores, mining and roasting wastes, and the river sediments. Widespread contamination of Tl was observed in the sediments across the river, with the highest concentration of Tl (17.3 mg/kg) measured 4 km downstream from the pyrite industrial site. Application of a modified Institute for Reference Materials and Measurement (IRMM) sequential extraction scheme in representative sediments unveiled that 60-90% of Tl and Pb were present in the residual fraction of the sediments. The sediments contained generally lower (206)Pb/(207)Pb and higher (208)Pb/(206)Pb ratios compared with the natural Pb isotope signature (1.2008 and 2.0766 for (206)Pb/(207)Pb and (208)Pb/(206)Pb, respectively). These results suggested that a significant fraction of non-indigenous Pb could be attributed to the mining and roasting activities of pyrite ores, with low (206)Pb/(207)Pb (1.1539) and high (208)Pb/(206)Pb (2.1263). Results also showed that approximately 6-88% of Tl contamination in the sediments originated from the pyrite mining and roasting activities. This study highlights that Pb isotopic compositions could be used for quantitatively fingerprinting the sources of Tl contamination in sediments. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Degradation of polycyclic aromatic hydrocarbons (PAHs) in an aged coal tar contaminated soil under in-vessel composting conditions

    International Nuclear Information System (INIS)

    Antizar-Ladislao, Blanca; Lopez-Real, Joe; Beck, Angus James

    2006-01-01

    In-vessel composting of polycyclic aromatic hydrocarbons (PAHs) present in contaminated soil from a manufactured gas plant site was investigated over 98 days using laboratory-scale in-vessel composting reactors. The composting reactors were operated at 18 different operational conditions using a 3-factor factorial design with three temperatures (T, 38 deg. C, 55 deg. C and 70 deg. C), four soil to green waste ratios (S:GW, 0.6:1, 0.7:1, 0.8:1 and 0.9:1 on a dry weight basis) and three moisture contents (MC, 40%, 60% and 80%). PAH losses followed first order kinetics reaching 0.015 day -1 at optimal operational conditions. A factor analysis of the 18 different operational conditions under investigation indicated that the optimal operational conditions for degradation of PAHs occurred at MC 60%, S:GW 0.8:1 and T 38 deg. C. Thus, it is recommended to maintain operational conditions during in-vessel composting of PAH-solid waste close to these values. - Maximum degradation of PAHs in an aged coal tar contaminated soil can be achieved using optimal operational conditions during composting

  12. Contamination of harbor sediments in the eastern Gulf of Finland (Neva Bay), Baltic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Ussenkov, S.M. [Dept. of Lithology and Marine Geology, Faculty of Geology, St. Petersburg State Univ. (Russian Federation)

    1997-11-01

    The areal distribution of oil products and various trace metals have been studied in bottom surface deposits from the harbors of Neva Bay. The data of contents were normalized to natural background concentrations. Also the size and biomass of benthos groups were analyzed. The results show clearly that industrial discharges have elevated levels of contamination in the sediments. Few efficient measures against environmental contamination have been taken. The sediments contain very high concentrations of oil products and such heavy metals as Hg, Pb, Cu, and Zn. The benthic organisms most sensitive to heavy metal contamination are Chironomidae. The dredging and dumping of the contaminated deposits can lead to secondary contamination of the Gulf of Finland and the Baltic proper. (orig.)

  13. Technology unlocks tar sands energy

    Energy Technology Data Exchange (ETDEWEB)

    Law, C

    1967-09-25

    Tar sand processing technology has been developed primarily in the categories of extraction techniques and in-situ processing. In October, a $235 million venture into tar sand processing will be inspected by visitors from many points on the globe. A synthetic crude of premium quality will be flowing through a 16-in. pipeline from the Tar Island plant site of Great Canadian Oil Sands to Edmonton. This processing plant uses an extractive mining technique. The tar sand pay zone in this area averages approximately 150 ft in thickness with a 50-ft overburden. It has been estimated that the tar sands cannot be exploited when the formation thickness is less than 100 ft and overburden exceeds the same amount. This indicates that extraction techniques can only be used to recover approximately 15% of the tar sand deposits. An in-situ recovery technique developed by Shell of Canada is discussed in detail. In essence it is selective hydraulic fracturing, followed by the injection of emulsifying chemicals and steam.

  14. PCB dechlorination hotspots and reductive dehalogenase genes in sediments from a contaminated wastewater lagoon.

    Science.gov (United States)

    Mattes, Timothy E; Ewald, Jessica M; Liang, Yi; Martinez, Andres; Awad, Andrew; Richards, Patrick; Hornbuckle, Keri C; Schnoor, Jerald L

    2017-08-12

    Polychlorinated biphenyls (PCBs) are a class of persistent organic pollutants that are distributed worldwide. Although industrial PCB production has stopped, legacy contamination can be traced to several different commercial mixtures (e.g., Aroclors in the USA). Despite their persistence, PCBs are subject to naturally occurring biodegradation processes, although the microbes and enzymes involved are poorly understood. The biodegradation potential of PCB-contaminated sediments in a wastewater lagoon located in Virginia (USA) was studied. Total PCB concentrations in sediments ranged from 6.34 to 12,700 mg/kg. PCB congener profiles in sediment sample were similar to Aroclor 1248; however, PCB congener profiles at several locations showed evidence of dechlorination. The sediment microbial community structure varied among samples but was dominated by Proteobacteria and Firmicutes. The relative abundance of putative dechlorinating Chloroflexi (including Dehalococcoides sp.) was 0.01-0.19% among the sediment samples, with Dehalococcoides sp. representing 0.6-14.8% of this group. Other possible PCB dechlorinators present included the Clostridia and the Geobacteraceae. A PCR survey for potential PCB reductive dehalogenase genes (RDases) yielded 11 sequences related to RDase genes in PCB-respiring Dehalococcoides mccartyi strain CG5 and PCB-dechlorinating D. mccartyi strain CBDB1. This is the first study to retrieve potential PCB RDase genes from unenriched PCB-contaminated sediments.

  15. Chemical speciation and transformation of mercury in contaminated sediments

    OpenAIRE

    Drott, Andreas

    2009-01-01

    Biomagnification of mercury (Hg) in aquatic food webs occurs almost exclusively as mono-methyl Hg (MeHg). In this thesis, the influence of chemical speciation and environmental conditions on transformations of inorganic Hg (HgII) and MeHg was studied at eight sites in Sweden with Hg contaminated sediments. The source of contamination was either Hg0(l) or phenyl-Hg, and total Hg concentrations ranged between 1.0-1100 nmol g-1. The environmental conditions, e.g. salinity, temperature climate, p...

  16. Assessment of the genotoxic potential of contaminated estuarine sediments in fish peripheral blood: Laboratory versus in situ studies

    International Nuclear Information System (INIS)

    Costa, Pedro M.; Neuparth, Teresa S.; Caeiro, Sandra; Lobo, Jorge; Martins, Marta; Ferreira, Ana M.; Caetano, Miguel; Vale, Carlos; Angel DelValls, T.; Costa, Maria H.

    2011-01-01

    Juvenile Senegalese soles (Solea senegalensis) were exposed to estuarine sediments through 28-day laboratory and in situ (field) bioassays. The sediments, collected from three distinct sites (a reference plus two contaminated) of the Sado Estuary (W Portugal) were characterized for total organic matter, redox potential, fine fraction and for the levels of metals, polycyclic aromatic hydrocarbons (PAHs) and organochlorines, namely polychlorinated biphenyls (PCBs) and dichloro diphenyl tricholoethane plus its main metabolites (DDTs). Genotoxicity was determined in whole peripheral blood by the single-cell gel electrophoresis (SCGE or 'comet') assay and by scoring erythrocytic nuclear abnormalities (ENA). Analysis was complemented with the determination of lipid peroxidation in blood plasma by the thiobarbituric acid reactive substances (TBARS) protocol and cell type sorting. The results showed that exposure to contaminated sediments induced DNA fragmentation and clastogenesis. Still, laboratory exposure to the most contaminated sediment revealed a possible antagonistic effect between metallic and organic contaminants that might have been enhanced by increased bioavailability. The laboratory assay caused a more pronounced increase in ENA whereas a very significant increase in DNA fragmentation was observed in field-tested fish exposed to the reference sediment, which is likely linked to increased lipid peroxidation that probably occurred due to impaired access to food. Influence of natural pathogens was ruled out by unaltered leukocyte counts. The statistical integration of data correlated lipid peroxidation with biological variables such as fish length and weight, whereas the genotoxicity biomarkers were more correlated to sediment contamination. It was demonstrated that laboratory and field bioassays for the risk assessment of sediment contamination may yield different genotoxicity profiles although both provided results that are in overall accordance with sediment

  17. Assessment of the genotoxic potential of contaminated estuarine sediments in fish peripheral blood: Laboratory versus in situ studies

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Pedro M., E-mail: pmcosta@fct.unl.pt [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Neuparth, Teresa S. [CIIMAR-Centro Interdisciplinar de Investigacao Marinha e Ambiental, Laboratorio de Toxicologia Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto (Portugal); Caeiro, Sandra [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Departamento de Ciencias e Tecnologia, Universidade Aberta, Rua da Escola Politecnica, 141, 1269-001 Lisboa (Portugal); Lobo, Jorge [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Martins, Marta; Ferreira, Ana M.; Caetano, Miguel; Vale, Carlos [IPIMAR-INRB, Instituto Nacional dos Recursos Biologicos, Avenida de Brasilia, 1449-006 Lisboa (Portugal); Angel DelValls, T. [UNESCO/UNITWIN/WiCop Chair-Departamento de Quimica Fisica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cadiz, Poligono rio San Pedro s/n, 11510 Puerto Real, Cadiz (Spain); Costa, Maria H. [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2011-01-15

    Juvenile Senegalese soles (Solea senegalensis) were exposed to estuarine sediments through 28-day laboratory and in situ (field) bioassays. The sediments, collected from three distinct sites (a reference plus two contaminated) of the Sado Estuary (W Portugal) were characterized for total organic matter, redox potential, fine fraction and for the levels of metals, polycyclic aromatic hydrocarbons (PAHs) and organochlorines, namely polychlorinated biphenyls (PCBs) and dichloro diphenyl tricholoethane plus its main metabolites (DDTs). Genotoxicity was determined in whole peripheral blood by the single-cell gel electrophoresis (SCGE or 'comet') assay and by scoring erythrocytic nuclear abnormalities (ENA). Analysis was complemented with the determination of lipid peroxidation in blood plasma by the thiobarbituric acid reactive substances (TBARS) protocol and cell type sorting. The results showed that exposure to contaminated sediments induced DNA fragmentation and clastogenesis. Still, laboratory exposure to the most contaminated sediment revealed a possible antagonistic effect between metallic and organic contaminants that might have been enhanced by increased bioavailability. The laboratory assay caused a more pronounced increase in ENA whereas a very significant increase in DNA fragmentation was observed in field-tested fish exposed to the reference sediment, which is likely linked to increased lipid peroxidation that probably occurred due to impaired access to food. Influence of natural pathogens was ruled out by unaltered leukocyte counts. The statistical integration of data correlated lipid peroxidation with biological variables such as fish length and weight, whereas the genotoxicity biomarkers were more correlated to sediment contamination. It was demonstrated that laboratory and field bioassays for the risk assessment of sediment contamination may yield different genotoxicity profiles although both provided results that are in overall accordance with

  18. Cytotoxicity of TiO2 nanoparticles towards freshwater sediment microorganisms at low exposure concentrations

    International Nuclear Information System (INIS)

    Kumari, Jyoti; Kumar, Deepak; Mathur, Ankita; Naseer, Arif; Kumar, Ravi Ranjan; Thanjavur Chandrasekaran, Prathna; Chaudhuri, Gouri; Pulimi, Mrudula; Raichur, Ashok M.; Babu, S.; Chandrasekaran, Natarajan; Nagarajan, R.; Mukherjee, Amitava

    2014-01-01

    There is a persistent need to assess the effects of TiO 2 nanoparticles on the aquatic ecosystem owing to their increasing usage in consumer products and risk of environmental release. The current study is focused on TiO 2 nanoparticle-induced acute toxicity at sub-ppm level (≤1 ppm) on the three different freshwater sediment bacterial isolates and their consortium under two different irradiation (visible light and dark) conditions. The consortium of the bacterial isolates was found to be less affected by the exposure to the nanoparticles compared to the individual cells. The oxidative stress contributed considerably towards the cytotoxicity under both light and dark conditions. A statistically significant increase in membrane permeability was noted under the dark conditions as compared to the light conditions. The optical and fluorescence microscopic images showed aggregation and chain formation of the bacterial cells, when exposed to the nanoparticles. The electron microscopic (SEM, TEM) observations suggested considerable damage of cells and bio-uptake of nanoparticles. The exopolysaccrides (EPS) production and biofilm formation were noted to increase in the presence of the nanoparticles, and expression of the key genes involved in biofilm formation was studied by RT-PCR. - Highlights: • Toxicity of NPs towards freshwater sediment bacteria at sub-ppm concentrations. • Decreased toxicity of the nanoparticles in the consortium of microorganisms. • Enhanced bacterial resistance through EPS and biofilm formation in the presence of NPs. • Considerable surface damage of cells and internalization of NPs. • Gene expression analyses related to biofilm formation in the presence of NPs

  19. Detection by denaturing gradient gel electrophoresis of ammonia-oxidizing bacteria in microcosms of crude oil-contaminated mangrove sediments.

    Science.gov (United States)

    dos Santos, A C F; Marques, E L S; Gross, E; Souza, S S; Dias, J C T; Brendel, M; Rezende, R P

    2012-01-27

    Currently, the effect of crude oil on ammonia-oxidizing bacterium communities from mangrove sediments is little understood. We studied the diversity of ammonia-oxidizing bacteria in mangrove microcosm experiments using mangrove sediments contaminated with 0.1, 0.5, 1, 2, and 5% crude oil as well as non-contaminated control and landfarm soil from near an oil refinery in Camamu Bay in Bahia, Brazil. The evolution of CO(2) production in all crude oil-contaminated microcosms showed potential for mineralization. Cluster analysis of denaturing gradient gel electrophoresis-derived samples generated with primers for gene amoA, which encodes the functional enzyme ammonia monooxygenase, showed differences in the sample contaminated with 5% compared to the other samples. Principal component analysis showed divergence of the non-contaminated samples from the 5% crude oil-contaminated sediment. A Venn diagram generated from the banding pattern of PCR-denaturing gradient gel electrophoresis was used to look for operational taxonomic units (OTUs) in common. Eight OTUs were found in non-contaminated sediments and in samples contaminated with 0.5, 1, or 2% crude oil. A Jaccard similarity index of 50% was found for samples contaminated with 0.1, 0.5, 1, and 2% crude oil. This is the first study that focuses on the impact of crude oil on the ammonia-oxidizing bacterium community in mangrove sediments from Camamu Bay.

  20. Anaerobic U(IV) Bio-oxidation and the Resultant Remobilization of Uranium in Contaminated Sediments

    International Nuclear Information System (INIS)

    Coates, John D.

    2005-01-01

    A proposed strategy for the remediation of uranium (U) contaminated sites is based on immobilizing U by reducing the oxidized soluble U, U(VI), to form a reduced insoluble end product, U(IV). Due to the use of nitric acid in the processing of nuclear fuels, nitrate is often a co-contaminant found in many of the environments contaminated with uranium. Recent studies indicate that nitrate inhibits U(VI) reduction in sediment slurries. However, the mechanism responsible for the apparent inhibition of U(VI) reduction is unknown, i.e. preferential utilization of nitrate as an electron acceptor, direct biological oxidation of U(IV) coupled to nitrate reduction, and/or abiotic oxidation by intermediates of nitrate reduction. Recent studies indicates that direct biological oxidation of U(IV) coupled to nitrate reduction may exist in situ, however, to date no organisms have been identified that can grow by this metabolism. In an effort to evaluate the potential for nitrate-dependent bio-oxidation of U(IV) in anaerobic sedimentary environments, we have initiated the enumeration of nitrate-dependent U(IV) oxidizing bacteria. Sediments, soils, and groundwater from uranium (U) contaminated sites, including subsurface sediments from the NABIR Field Research Center (FRC), as well as uncontaminated sites, including subsurface sediments from the NABIR FRC and Longhorn Army Ammunition Plant, Texas, lake sediments, and agricultural field soil, sites served as the inoculum source. Enumeration of the nitrate-dependent U(IV) oxidizing microbial population in sedimentary environments by most probable number technique have revealed sedimentary microbial populations ranging from 9.3 x 101 - 2.4 x 103 cells (g sediment)-1 in both contaminated and uncontaminated sites. Interestingly uncontaminated subsurface sediments (NABIR FRC Background core FB618 and Longhorn Texas Core BH2-18) both harbored the most numerous nitrate-dependent U(IV) oxidizing population 2.4 x 103 cells (g sediment)-1

  1. Local to regional scale industrial heavy metal pollution recorded in sediments of large freshwater lakes in central Europe (lakes Geneva and Lucerne) over the last centuries

    International Nuclear Information System (INIS)

    Thevenon, Florian; Graham, Neil D.; Chiaradia, Massimo; Arpagaus, Philippe; Wildi, Walter; Poté, John

    2011-01-01

    This research first focuses on the spatial and temporal patterns of heavy metals from contrasting environments (highly polluted to deepwater sites) of Lake Geneva. The mercury (Hg) and lead (Pb) records from two deepwater sites show that the heavy metal variations before the industrial period are primarily linked to natural weathering input of trace elements. By opposition, the discharge of industrial treated wastewaters into Vidy Bay of Lake Geneva during the second part of the 20th century, involved the sedimentation of highly metal-contaminated sediments in the area surrounding the WWTP outlet pipe discharge. Eventually, a new Pb isotope record of sediments from Lake Lucerne identifies the long-term increasing anthropogenic lead pollution after ca. 1500, probably due to the development of metallurgical activities during the High Middle Ages. These data furthermore allows to compare the recent anthropogenic sources of water pollution from three of the largest freshwater lakes of Western Europe (lakes Geneva, Lucerne, and Constance). High increases in Pb and Hg highlight the regional impact of industrial pollution after ca. 1750–1850, and the decrease of metal pollution in the 1980s due to the effects of remediation strategies such as the implementation of wastewater treatment plants (WWTPs). However, at all the studied sites, the recent metal concentrations remain higher than pre-industrial levels. Moreover, the local scale pollution data reveal two highly contaminated sites (> 100 μg Pb/g dry weight sediment) by industrial activities, during the late-19th and early-20th centuries (Lake Lucerne) and during the second part of the 20th century (Vidy Bay of Lake Geneva). Overall, the regional scale pollution history inferred from the three large and deep perialpine lakes points out at the pollution of water systems by heavy metals during the last two centuries due to the discharge of industrial effluents. Highlights: ► Natural sources dominated trace element

  2. Characterization of Contaminant Migration Potential Through In-Place Sediment Caps

    Science.gov (United States)

    2011-06-01

    grab. Extraction and analysis of sediment/cap material used pesticide -grade organic solvents obtained from Fisher Scientific (Pittsburgh, PA). The 16...34Controlled Field Release of a Bioluminescent Genetically Engineered  Microorganism  for  Bioremediation  Process Monitoring and Control." Environmental Science...role of sorbent amendments in enhancing cap performance. Laboratory column experiments were performed using contaminated sediments and capping

  3. Monitoring of organic contaminants in sediments using low field proton nuclear magnetic resonance

    Science.gov (United States)

    Zhang, Chi; Rupert, Yuri

    2016-04-01

    The effective monitoring of soils and groundwater contaminated with organic compounds is an important goal of many environmental restoration efforts. Recent geophysical methods such as electrical resistivity, complex conductivity, and ground penetrating radar have been successfully applied to characterize organic contaminants in the subsurface and to monitor remediation process both in laboratory and in field. Low field proton nuclear magnetic resonance (NMR) is a geophysical tool sensitive to the molecular-scale physical and chemical environment of hydrogen-bearing fluids in geological materials and shows promise as a novel method for monitoring contaminant remediation. This laboratory research focuses on measurements on synthetic samples to determine the sensitivity of NMR to the presence of organic contaminants and improve understanding of relationships between NMR observables, hydrological properties of the sediments, and amount and state of contaminants in porous media. Toluene, a light non-aqueous phase liquid (LNAPL) has been selected as a representative organic contaminant. Three types of porous media (pure silica sands, montmorillonite clay, and various sand-clay mixtures with different sand/clay ratios) were prepared as synthetic sediments. NMR relaxation time (T2) and diffusion-relaxation (D - T2) correlation measurements were performed in each sediment saturated with water and toluene mixed fluid at assorted concentrations (0% toluene and 100% water, 1% toluene and 99% water, 5% toluene and 95% water, 25% toluene and 75% water, and 100% toluene and 0% water) to 1) understand the effect of different porous media on the NMR responses in each fluid mixture, 2) investigate the role of clay content on T2 relaxation of each fluid, 3) quantify the amount hydrocarbons in the presence of water in each sediment, and 4) resolve hydrocarbons from water in D - T2 map. Relationships between the compositions of porous media, hydrocarbon concentration, and hydraulic

  4. MANAGING ARSENIC CONTAMINATED SOIL, SEDIMENT, AND INDUSTRIAL WASTE WITH SOLIDIFICATION/STABILIZATION TREATMENT

    Science.gov (United States)

    Arsenic contamination of soil, sediment and groundwater is a widespread problem in certain areas and has caused great public concern due to increased awareness of the health risks. Often the contamination is naturally occurring, but it can also be a result of waste generated from...

  5. Release of Aged Contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

    Energy Technology Data Exchange (ETDEWEB)

    Chorover, Jon [Univ. of Arizona, Tucson, AZ (United States); Perdrial, Nico [Univ. of Arizona, Tucson, AZ (United States); Mueller, Karl [Pennsylvania State Univ., University Park, PA (United States); Strepka, Caleb [Pennsylvania State Univ., University Park, PA (United States); O' Day, Peggy [Univ. of California, Merced, CA (United States); Rivera, Nelson [Univ. of California, Merced, CA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chang, Hyun-Shik [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Steefel, Carl [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Thompson, Aaron [Univ. of Georgia, Athens, GA (United States)

    2012-08-14

    Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake (Chorover et al., 2008). In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, PCO2, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. Below, we provide some detailed descriptions of our results from this three year study, recently completed following a one-year no cost extension.

  6. Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

    Energy Technology Data Exchange (ETDEWEB)

    Chorover, Jon; Perdrial, Nico; Mueller, Karl; Strepka, Caleb; O’Day, Peggy; Rivera, Nelson; Um, Wooyong; Chang, Hyun-Shik; Steefel, Carl; Thompson, Aaron

    2012-11-05

    Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, partial pressure of carbon dioxide, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. In this final report, we provide detailed descriptions of our results from this three-year study, completed in 2012 following a one-year no cost extension.

  7. Histological biomarkers in liver and gills of juvenile Solea senegalensis exposed to contaminated estuarine sediments: A weighted indices approach

    International Nuclear Information System (INIS)

    Costa, Pedro M.; Diniz, Mario S.; Caeiro, Sandra; Lobo, Jorge; Martins, Marta; Ferreira, Ana M.; Caetano, Miguel; Vale, Carlos; DelValls, T. Angel; Costa, M. Helena

    2009-01-01

    Young juvenile Solea senegalensis were exposed to three sediments with distinct contamination profiles collected from a Portuguese estuary subjected to anthropogenic sources of contamination (the Sado estuary, western Portugal). Sediments were surveyed for metals (cadmium, chromium, copper, nickel, lead and zinc), a metalloid (arsenic) and organic contaminants (polycyclic aromatic hydrocarbons, polychlorinated biphenyls and a pesticide, dichloro-diphenyl-trichloroethane plus its metabolites), as well as total organic matter, redox potential and particle fine fraction. The fish were exposed to freshly collected sediments in a 28-day laboratorial assay and collected for histological analyses at days 0 (T 0 ), 14 (T 14 ) and 28 (T 28 ). Individual weighted histopathological indices were obtained, based on presence/absence data of eight and nine liver and gill pathologies, respectively, and on their biological significance. Although livers sustained more severe lesions, the sediments essentially contaminated by organic substances caused more damage to both organs than the sediments contaminated by both metallic and organic contaminants, suggesting a possible synergistic effect. Correlation analyses showed that some alterations are linked, forming distinctive histopathological patterns that are in accordance with the severity of lesions and sediment characteristics. The presence of large eosinophilic bodies in liver and degeneration of mucous cells in gills (a first-time described alteration) were some of the most noticeable alterations observed and were related to sediment organic contaminants. Body size has been found to be negatively correlated with histopathological damage in livers following longer term exposures. It is concluded that histopathological indices provide reliable and discriminatory data even when biomonitoring as complex media as natural sediments. It is also concluded that the effects of contamination may result not only from toxicant concentrations

  8. Contamination of freshwater fish from rivers Sava and Danube with polychlorinated biphenyls

    International Nuclear Information System (INIS)

    Jankovic, S.; Radicevic, T.; Spiric, A.; Nedeljkovic, M.

    2002-01-01

    During air strikes, in april 1999, Institute of meat hygiene and technology have begun examination of freshwater fish to establish the degree of contamination. The information about damaged industrial facilities and toxic waste that have been spilled were hard to find, and was unofficial and contradicts. Because of that, at the first time we collected samples from different locations, but after first results, we concentrated our attention on locations on river Danube downstream from Pancevo and on river Sava upstream from Belgrade, the locations indicated as environmental 'hot spots'. According to our experience, knowledge, equipment and analytical skills we have chosen to determine the concentrations of PCBs in freshwater fish species, since aquatic fauna might be used as indicator organisms for the evaluation of water pollution. Polychlorinated biphenyls as contaminant of interest, have been chosen because large quantities of PCBs reached the soil and waste and ground waters from damaged transformers and capacitors, where they serve as dielectric fluids. Also, PCBs are highly toxic and due to their liposolubility and persistence, these compounds accumulate through food chain. In 1999, from April to December, we had collected 23 samples of different fish species on river Danube, downstream from Pancevo and 15 samples from locations on river Sava upstream from Belgrade. The concentrations of PCBs (mg/kg fat and mg/kg fresh weight) were expressed as the sum of individual congeners (IUPAC numbers 28, 52, 101, 138, 153, 180) and as Aroclor 1260 (peaks were identified as a fingerprint pattern by comparison with Aroclor standards). The concentrations of PCBs (mg/kg fat) are determined to evaluate the extent of contamination and concentrations of PCBs (mg/kg fresh weight) indicate daily intake and help us to estimate the risk for human health. Residues of PCBs in the fat extracted from fish sample were analysed according to the USDA Analytical Chemistry Guidebook. Gas

  9. Unexpected and novel putative viruses in the sediments of a deep-dark permanently anoxic freshwater habitat.

    Science.gov (United States)

    Borrel, Guillaume; Colombet, Jonathan; Robin, Agnès; Lehours, Anne-Catherine; Prangishvili, David; Sime-Ngando, Télesphore

    2012-11-01

    Morphological diversity, abundance and community structure of viruses were examined in the deep and anoxic sediments of the volcanic Lake Pavin (France). The sediment core, encompassing 130 years of sedimentation, was subsampled every centimeter. High viral abundances were recorded and correlated to prokaryotic densities. Abundances of viruses and prokaryotes decreased with the depth, contrasting the pattern of virus-to-prokaryote ratio. According to fingerprint analyses, the community structure of viruses, bacteria and archaea gradually changed, and communities of the surface (0-10 cm) could be discriminated from those of the intermediate (11-27 cm) and deep (28-40 cm) sediment layers. Viral morphotypes similar to virions of ubiquitous dsDNA viruses of bacteria were observed. Exceptional morphotypes, previously never reported in freshwater systems, were also detected. Some of these resembled dsDNA viruses of hyperthermophilic and hyperhalophilic archaea. Moreover, unusual types of spherical and cubic virus-like particles (VLPs) were observed. Infected prokaryotic cells were detected in the whole sediment core, and their vertical distribution correlated with both viral and prokaryotic abundances. Pleomorphic ellipsoid VLPs were visible in filamentous cells tentatively identified as representatives of the archaeal genus Methanosaeta, a major group of methane producers on earth.

  10. Kinetics of hydrophobic organic contaminant extraction from sediment by granular activated carbon.

    Science.gov (United States)

    Rakowska, M I; Kupryianchyk, D; Smit, M P J; Koelmans, A A; Grotenhuis, J T C; Rijnaarts, H H M

    2014-03-15

    Ex situ solid phase extraction with granular activated carbon (GAC) is a promising technique to remediate contaminated sediments. The methods' efficiency depends on the rate by which contaminants are transferred from the sediment to the surface of GAC. Here, we derive kinetic parameters for extraction of polycyclic aromatic hydrocarbons (PAH) from sediment by GAC, using a first-order multi-compartment kinetic model. The parameters were obtained by modeling sediment-GAC exchange kinetic data following a tiered model calibration approach. First, parameters for PAH desorption from sediment were calibrated using data from systems with 50% (by weight) GAC acting as an infinite sink. Second, the estimated parameters were used as fixed input to obtain GAC uptake kinetic parameters in sediment slurries with 4% GAC, representing the ex situ remediation scenario. PAH uptake rate constants (kGAC) by GAC ranged from 0.44 to 0.0005 d(-1), whereas GAC sorption coefficients (KGAC) ranged from 10(5.57) to 10(8.57) L kg(-1). These values are the first provided for GAC in the presence of sediment and show that ex situ extraction with GAC is sufficiently fast and effective to reduce the risks of the most available PAHs among those studied, such as fluorene, phenanthrene and anthracene. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Upgrading of hydropyrolysis coal tar by hydroprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Haglund, R.; Otterstedt, J.E.; Sterte, J. (Chalmers Univ. of Tech., Goeteborg (Sweden). 1. Dept. of Engineering Chemistry)

    1991-05-01

    Upgrading of a hydropyrolysis coal tar by hydroprocessing was investigated using different process conditions. The response of the hydropyrolysis tar to hydroprocessing was compared to those of a conventional coal tar and two heavy oil fractions. At comparable conditions, the removal of heteroatoms from the hydropyrolysis tar was more effective than from the conventional tar and, in particular, than from the oil fractions. Using conditions typical for hydroprocessing of heavy oil fractions, the contents of N, O as well as S in the hydropyrolysis tar were reduced by more than 90%. Hydroprocessing also resulted in a considerable increase in the gasoline fraction of the tar. (orig.).

  12. Simulation of ground-water flow in the St. Peter aquifer in an area contaminated by coal-tar derivatives, St. Louis Park, Minnesota. Water Resources Investigation

    International Nuclear Information System (INIS)

    Lorenz, D.L.; Stark, J.R.

    1990-01-01

    A model constructed to simulate ground-water flow in part of the Prairie du Chien-Jordan and St. Peter aquifers, St. Louis Park, Minnesota, was used to test hypotheses about the movement of ground water contaminated with coal-tar derivatives and to simulate alternatives for reducing the downgradient movement of contamination in the St. Peter aquifer. The model, constructed for a previous study, was applied to simulate the effects of current ground-water withdrawals on the potentiometric surface of the St. Peter aquifer. Model simulations predict that the multiaquifer wells have the potential to limit downgradient migration of contaminants in the St. Peter aquifer caused by cones of depression created around the multiaquifer wells. Differences in vertical leakage to the St. Peter aquifer may exist in areas of bedrock valleys. Model simulations indicate that these differences are not likely to affect significantly the general patterns of ground-water flow

  13. Persistent organochlorine pesticide residues in freshwater systems ...

    African Journals Online (AJOL)

    DRINIE

    determined in water and sediment samples of freshwater systems in the Eastern Cape Province of South Africa that ... The organochlorine pesticides (OCPs) in water and sediments ...... Test Methods For Evaluating Solid Waste (3rd edn.) ...

  14. Assessing the Extent of Sediment Contamination Around Creosote-treated Pilings Through Chemical and Biological Analyses

    Science.gov (United States)

    Stefansson, E. S.

    2008-12-01

    Creosote is a common wood preservative used to treat marine structures, such as docks and bulkheads. Treated dock pilings continually leach polycyclic aromatic hydrocarbons (PAHs) and other creosote compounds into the surrounding water and sediment. Over time, these compounds can accumulate in marine sediments, reaching much greater concentrations than those in seawater. The purpose of this study was to assess the extent of creosote contamination in sediments, at a series of distances from treated pilings. Three pilings were randomly selected from a railroad trestle in Fidalgo Bay, WA and sediment samples were collected at four distances from each: 0 meters, 0.5 meters, 1 meter, and 2 meters. Samples were used to conduct two bioassays: an amphipod bioassay (Rhepoxynius abronius) and a sand dollar embryo bioassay. Grain size and PAH content (using a fluorometric method) were also measured. Five samples in the amphipod bioassay showed significantly lower effective survival than the reference sediment. These consisted of samples closest to the piling at 0 and 0.5 meters. One 0 m sample in the sand dollar embryo bioassay also showed a significantly lower percentage of normal embryos than the reference sediment. Overall, results strongly suggest that creosote-contaminated sediments, particularly those closest to treated pilings, can negatively affect both amphipods and echinoderm embryos. Although chemical data were somewhat ambiguous, 0 m samples had the highest levels of PAHs, which corresponded to the lowest average survival in both bioassays. Relatively high levels of PAHs were found as far as 2 meters away from pilings. Therefore, we cannot say how far chemical contamination can spread from creosote-treated pilings, and at what distance this contamination can still affect marine organisms. These results, as well as future research, are essential to the success of proposed piling removal projects. In addition to creosote-treated pilings, contaminated sediments must

  15. Physicochemical Approaches for the Remediation of Former Manufactured Gas Plant Tars

    Science.gov (United States)

    Hauswirth, S.; Miller, C. T.

    2014-12-01

    Former manufactured gas plant (FMGP) tars are one of the most challenging non-aqueous phase liquid (NAPL) contaminants to remediate due to their complex chemical composition, high viscosities, and ability to alter wettability. In this work, we investigate several in situ remediation techniques for the removal of tar from porous media. Batch and column experiments were conducted to test the effectiveness of mobilization, solubilization, and chemical oxidation remediation approaches. Alkaline (NaOH), surfactant (Triton X-100), and polymer (xanthan gum) agents were used in various combinations to reduce tar-water interfacial tension, increase flushing solution viscosity, and increase the solubilities of tar components. Base-activated sodium persulfate was used alone and in combination with surfactant to chemically oxidized tar components. The effectiveness of each method was assessed in terms of both removal of PAHs from the system and reduction of dissolved-phase effluent polycyclic aromatic hydrocarbon (PAH) concentrations. In column studies, alkaline-polymer (AP) and alkaline-surfactant-polymer (ASP) solutions efficiently mobilized 81-93% and 95-96% of residual PAHs, respectively, within two pore volumes. The impact of AP flushing on dissolved-phase PAH concentrations was relatively low; however, the concentrations of several low molar mass PAHs were significantly reduced after ASP flushing. Surfactant-polymer (SP) solutions removed over 99% of residual PAHs through a combination of mobilization and solubilization, and reduced the post-remediation, dissolved-phase total PAH concentration by 98.4-99.1%. Degradation of residual PAHs by base-activated sodium persulfate was relatively low (30-50%), and had little impact on dissolved-phase PAH concentrations.

  16. Nickel, Lead and Zinc Contamination in the Surface Sediments of Agh Gel Wetland, Iran

    Directory of Open Access Journals (Sweden)

    Soheil Sobhan Ardakani

    2016-07-01

    Full Text Available Background & Aims of the Study: Due to the increased human activities around the Agh Gel wetland, this study aimed to measured accumulations of heavy metals (Ni, Pb and Zn in the surface sediment samples taken from this wetland. Materials & Methods: Samples were taken from 10 stations and exposed to bulk digestion and chemical partitioning. Finally, Ni, Pb and Zn concentrations were monitored with ICP-OES in the sediments. Also, geo-accumulation index, contamination factor and pollution load index were used to evaluate the magnitude of contaminants in the sediment profile. Results: The results showed, the average of metal concentration in samples (mg kg-1 wet weight were 34.20±3.58 for Ni, 25.37±2.52 for Pb and 127.20±15.21 for Zn, respectively. Therefore, the pattern of metal concentrations in sediment was determined as Zinc>Nickel >Lead. According to the mean I-geo values, sediments' qualities are classified as unpolluted category for Ni and Pb. Also, sediment's quality is classified as unpolluted to moderately polluted for Zn. The CF values for all elements are classified as moderate contamination. The PLI values indicated that metal pollution exists for all sampling stations. Conclusions: The obtained results indicated that the Agh Gel wetland has a potential to threaten by chemical pollutants such as agricultural effluent. So, in order to preserve the environment of the Agh Gel wetland from deterioration, monitoring of water and sediment qualities is recommended periodically.

  17. USING SPMDS TO ACCESS MANAGMENT STRATEGIES FOR PCB CONTAMINATED SEDIMENTS

    Science.gov (United States)

    Dredging, in-place treatment, capping and monitored natural recovery, used together or separately are the primary approaches for managing contaminated sediment risks. Understanding how well different approaches work in different environments is critical for choosing an appropria...

  18. Preliminary evaluation of heavy metal contamination in the Zarrin-Gol River sediments, Iran.

    Science.gov (United States)

    Malvandi, Hassan

    2017-04-15

    The major objectives of the study were to test the hypothesis of the Zarrin-Gol River as a reference site for ecotoxicological studies and to assess the contamination degree of heavy metals and metalloids in the river using four contamination indices. For these purposes, eleven heavy metal and metalloid concentrations were analyzed. The average concentrations (mgkg -1 ) in the sediments were: 37.67 (chromium) 286.28 (manganese), 13,751.04 (iron), 8.79 (cobalt), 12.39 (nickel), 32.68 (zinc), 21.91 (arsenic), 40.59 (selenium), 2923.86 (aluminum), ND (silver) and 785.96 (magnesium). Contamination factor, enrichment factor, pollution load index, and geoaccumulation index were calculated to evaluate the contamination degree and influence of human activities on heavy metal levels. The contamination indices of the sediment samples showed that arsenic and selenium were the highest pollutants. The results indicated that the Zarrin-Gol River could not be used as a reference site at least for arsenic and selenium. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Contaminants in stream sediments from seven United States metropolitan areas: part I: distribution in relation to urbanization

    Science.gov (United States)

    Nowell, Lisa H.; Moran, Patrick W.; Gilliom, Robert J.; Calhoun, Daniel L.; Ingersoll, Christopher G.; Kemble, Nile E.; Kuivila, Kathryn; Phillips, Patrick J.

    2013-01-01

    Organic contaminants and trace elements were measured in bed sediments collected from streams in seven metropolitan study areas across the United States to assess concentrations in relation to urbanization. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, organochlorine pesticides, the pyrethroid insecticide bifenthrin, and several trace elements were significantly related to urbanization across study areas. Most contaminants (except bifenthrin, chromium, nickel) were significantly related to the total organic carbon (TOC) content of the sediments. Regression models explained 45–80 % of the variability in individual contaminant concentrations using degree of urbanization, sediment-TOC, and study-area indicator variables (which represent the combined influence of unknown factors, such as chemical use or release, that are not captured by available explanatory variables). The significance of one or more study-area indicator variables in all models indicates marked differences in contaminant levels among some study areas, even after accounting for the nationally modeled effects of urbanization and sediment-TOC. Mean probable effect concentration quotients (PECQs) were significantly related to urbanization. Trace elements were the major contributors to mean PECQs at undeveloped sites, whereas organic contaminants, especially bifenthrin, were the major contributors at highly urban sites. Pyrethroids, where detected, accounted for the largest share of the mean PECQ. Part 2 of this series (Kemble et al. 2012) evaluates sediment toxicity to amphipods and midge in relation to sediment chemistry.

  20. Influence of a Brazilian sewage outfall on the toxicity and contamination of adjacent sediments

    Science.gov (United States)

    Abessa, D.M.S.; Carr, R.S.; Rachid, B.R.F.; Sousa, E.C.P.M.; Hortelani, M.A.; Sarkis, J.E.

    2005-01-01

    The submarine sewage outfall of Santos (SSOS) is situated in the Santos Bay (São Paulo, Brazil) and is potentially a significant source of contaminants to the adjacent marine ecosystem. The present study aimed to assess the influence of SSOS on the sediment toxicity and contamination at Santos Bay. At the disposal site, sediments tended to be finer, organically richer and exhibited higher levels of surfactants and metals, sometimes exceeding the “Threshold Effect Level” values. The SSOS influence was more evident toward the East, where the sediments exhibited higher levels of TOC, total S and metals during the summer 2000 sampling campaign. Sediment toxicity to amphipods was consistently detected in four of the five stations studied. Amphipod survival tended to correlate negatively to Hg, total N and % mud. This work provides evidence that the SSOS discharge affects the quality of sediments from Santos Bay, and that control procedures are warranted.

  1. COPING WITH CONTAMINATED SEDIMENTS AND SOILS IN THE URBAN ENVIRONMENT.

    Energy Technology Data Exchange (ETDEWEB)

    JONES,K.W.; VAN DER LELIE,D.; MCGUIGAN,M.; ET AL.

    2004-05-25

    Soils and sediments contaminated with toxic organic and inorganic compounds harmful to the environment and to human health are common in the urban environment. We report here on aspects of a program being carried out in the New York/New Jersey Port region to develop methods for processing dredged material from the Port to make products that are safe for introduction to commercial markets. We discuss some of the results of the program in Computational Environmental Science, Laboratory Environmental Science, and Applied Environmental Science and indicate some possible directions for future work. Overall, the program elements integrate the scientific and engineering aspects with regulatory, commercial, urban planning, local governments, and community group interests. Well-developed connections between these components are critical to the ultimate success of efforts to cope with the problems caused by contaminated urban soils and sediments.

  2. Polychlorinated biphenyl (PCB) contamination in Galveston Bay, Texas: Comparing concentrations and profiles in sediments, passive samplers, and fish.

    Science.gov (United States)

    Oziolor, Elias M; Apell, Jennifer N; Winfield, Zach C; Back, Jeffrey A; Usenko, Sascha; Matson, Cole W

    2018-05-01

    The industrialized portion of the Houston Ship Channel (HSC) is heavily contaminated with anthropogenic contaminants, most prominent of which are the polychlorinated biphenyls (PCBs). This contamination has driven adaptive evolution in a keystone species for Galveston Bay, the Gulf killifish (Fundulus grandis). We investigated the geographical extent of PCB impacts by sampling 12 sites, ranging from the heavily industrialized upper portion of the HSC to Galveston Island. At each site, PCB concentrations and profiles were determined in three environmental compartments: sediment, water (polyethylene passive samplers), and fish tissue (resident Gulf killifish). We observed a steep gradient of PCB contamination, ranging from 4.00 to 100,000 ng/g organic carbon in sediment, 290-110,000 ng/g lipid in fish, and 4.5-2300 ng/g polyethylene in passive samplers. The PCB congener profiles in Gulf killifish at the most heavily contaminated sites were shifted toward the higher chlorinated PCBs and were highly similar to the sediment contamination profiles. In addition, while magnitude of total PCB concentrations in sediment and total fish contamination levels were highly correlated between sites, the relative PCB congener profiles in fish and passive samplers were more alike. This strong correlation, along with a lack of dependency of biota-sediment accumulation factors with total contamination rates, confirm the likely non-migratory nature of Gulf killifish and suggest their contamination levels are a good site-specific indicator of contamination in the Galveston Bay area. The spatial gradient of PCB contamination in Galveston Bay was evident in all three matrices studied and was observed effectively using Gulf killifish contamination as an environmentally relevant bioindicator of localized contamination in this environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Human impact on fluvial sediments: distinguishing regional and local sources of heavy metals contamination

    Science.gov (United States)

    Novakova, T.; Matys Grygar, T.; Bábek, O.; Faměra, M.; Mihaljevič, M.; Strnad, L.

    2012-04-01

    Industrial pollution can provide a useful tool to study spatiotemporal distribution of modern floodplain sediments, trace their provenance, and allow their dating. Regional contamination of southern Moravia (the south-eastern part of the Czech Republic) by heavy metals during the 20th century was determined in fluvial sediments of the Morava River by means of enrichment factors. The influence of local sources and sampling sites heterogeneity were studied in overbank fines with different lithology and facies. For this purpose, samples were obtained from hand-drilled cores from regulated channel banks, with well-defined local sources of contamination (factories in Zlín and Otrokovice) and also from near naturally inundated floodplains in two nature protected areas (at 30 km distance). The analyses were performed by X-ray fluorescence spectroscopy (ED XRF), ICP MS (EDXRF samples calibration, 206Pb/207Pb ratio), magnetic susceptibility, cation exchange capacity (CEC), and 137Cs and 210Pb activities. Enrichment factors (EF) of heavy metals (Pb, Zn, Cu and Cr) and magnetic susceptibility of overbank fines in near-naturally (near annually) inundated areas allowed us to reconstruct historical contamination by heavy metals in the entire study area independently on lithofacies. Measured lithological background values were then used for calculation of EFs in the channel sediments and in floodplain sediments deposited within narrow part of a former floodplain which is now reduced to about one quarter of its original width by flood defences. Sediments from regulated channel banks were found stratigraphically and lithologically "erratic", unreliable for quantification of regional contamination due to a high variability of sedimentary environment. On the other hand, these sediments are very sensitive to the nearby local sources of heavy metals. For a practical work one must first choose whether large scale, i.e. a really averaged regional contamination should be reconstructed

  4. Contamination of port zone sediments by metals from Large Marine Ecosystems of Brazil.

    Science.gov (United States)

    Buruaem, Lucas M; Hortellani, Marcos A; Sarkis, Jorge E; Costa-Lotufo, Leticia V; Abessa, Denis M S

    2012-03-01

    Sediment contamination by metals poses risks to coastal ecosystems and is considered to be problematic to dredging operations. In Brazil, there are differences in sedimentology along the Large Marine Ecosystems in relation to the metal distributions. We aimed to assess the extent of Al, Fe, Hg, Cd, Cr, Cu, Ni, Pb and Zn contamination in sediments from port zones in northeast (Mucuripe and Pecém) and southeast (Santos) Brazil through geochemical analyses and sediment quality ratings. The metal concentrations found in these port zones were higher than those observed in the continental shelf or the background values in both regions. In the northeast, metals were associated with carbonate, while in Santos, they were associated with mud. Geochemical analyses showed enrichments in Hg, Cd, Cu, Ni and Zn, and a simple application of international sediment quality guidelines failed to predict their impacts, whereas the use of site-specific values that were derived by geochemical and ecotoxicological approaches seemed to be more appropriate in the management of the dredged sediments. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Plastic pollution in freshwater ecosystems: macro-, meso-, and microplastic debris in a floodplain lake.

    Science.gov (United States)

    Blettler, Martin C M; Ulla, Maria Alicia; Rabuffetti, Ana Pia; Garello, Nicolás

    2017-10-23

    Plastic pollution is considered an important environmental problem by the United Nations Environment Programme, and it is identified, alongside climate change, as an emerging issue that might affect biological diversity and human health. However, despite research efforts investigating plastics in oceans, relatively little studies have focused on freshwater systems. The aim of this study was to estimate the spatial distribution, types, and characteristics of macro-, meso-, and microplastic fragments in shoreline sediments of a freshwater lake. Food wrappers (mainly polypropylene and polystyrene), bags (high- and low-density polyethylene), bottles (polyethylene terephthalate), and disposable Styrofoam food containers (expanded polystyrene) were the dominant macroplastics recorded in this study. Contrary to other studies, herein macroplastic item surveys would not serve as surrogates for microplastic items. This is disadvantageous since macroplastic surveys are relatively easier to conduct. Otherwise, an average of 25 mesoplastics (mainly expanded polystyrene) and 704 microplastic particles (diverse resins) were recorded per square meter in sandy sediments. Comparisons with other studies from freshwater and marine beaches indicated similar relevance of plastic contamination, demonstrating for the first time that plastic pollution is a serious problem in the Paraná floodplain lakes. This study is also valuable from a social/educational point of view, since plastic waste has been ignored in the Paraná catchment as a pollutant problem, and therefore, the outcome of the current study is a relevant contribution for decision makers.

  6. Methymercury Formation in Marine and Freshwater Systems: Sediment Characteristics, Microbial Activity and SRB Phylogeny Control Formation Rates and Food-Chain Exposure

    Science.gov (United States)

    King, J. K.; Saunders, F. M.

    2004-05-01

    Mercury research in freshwater and marine systems suggests that sediment characteristics such as organic substrate, mercury speciation, and sulfate/sulfide concentrations influence availability of inorganic mercury for methylation. Similarly, sediment characteristics also influence sulfate-reducing bacterial (SRB) respiration as well as the presence/distribution of phylogenetic groups responsible for mercury methylation. Our work illustrates that the process of methylmercury formation in freshwater and marine systems are not dissimilar. Rather, the same geochemical parameters and SRB phylogenetic groups determine the propensity for methylmercury formation and are applicable in both fresh- and marine-water systems. The presentation will include our integration of sediment geochemical and microbial parameters affecting mercury methylation in specific freshwater and marine systems. Constructed wetlands planted with Schoenoplectus californicus and amended with gypsum (CaSO4) have demonstrated a capacity to remove inorganic mercury from industrial outfalls. However, bioaccumulation studies of periphyton, eastern mosquitofish (Gambusia holbrooki) and lake chubsucker (Erimyzon sucetta) were conducted in order to ascertain the availability of wetland-generated methylmercury to biota. Total mercury concentrations in mosquitofish from non-sulfate treated controls and the reference location were significantly lower than those from the low and high sulfate treatments while mean total mercury concentrations in lake chubsuckers were also significantly elevated in the high sulfate treatment compared to the low sulfate, control and reference populations. Methylmercury concentrations in periphyton also corresponded with mercury levels found in the tissue of the lake chubsuckers, and these findings fit well given the trophic levels identified for both species of fish. Overall, data from this study suggest that the initial use of gypsum to accelerate the maturity of a constructed

  7. Linking metatranscriptomic to bioremediation processes of oil contaminated marine sediments

    Science.gov (United States)

    Cuny, P.; Atkinson, A.; Léa, S.; Guasco, S.; Jezequel, R.; Armougom, F.; Michotey, V.; Bonin, P.; Militon, C.

    2016-02-01

    Oil-derived hydrocarbons are one major source of pollution of marine ecosystems. In coastal marine areas they tend to accumulate in the sediment where they can impact the benthic communities. Oil hydrocarbons biodegradation by microorganisms is known to be one of the prevalent processes acting in the removal of these contaminants from sediments. The redox oscillation regimes generated by bioturbation, and the efficiency of metabolic coupling between functional groups associated to these specific redox regimes, are probably determinant factors controlling hydrocarbon biodegradation. Metatranscriptomic analysis appears like a promising approach to shed new light on the metabolic processes involved in the response of microbial communities to oil contamination in such oxic/anoxic oscillating environments. In the framework of the DECAPAGE project (ANR CESA-2011-006 01), funded by the French National Agency for Research, the metatranscriptomes (RNA-seq) of oil contaminated or not (Ural blend crude oil, 5 000 ppm) and bioturbated or not (addition of the common burrowing organism Hediste diversicolor, 1000 ind/m2) mudflat sediments, incubated in microcosms during 4 months at 19±1°C, were compared. The analysis of active microbial communities by SSU rRNA barcoding shows that the main observable changes are due to the presence of H. diversicolor. On the contrary, oil addition is the main factor explaining the observed changes in the genes expression patterns with 1949 genes specifically up or down-regulated (which is the case of only 245 genes when only H. diversicolor worms are added). In particular, the oil contamination leads to a marked overexpression (i) of benzyl- and alkylsuccinate synthase genes (ass and bss) that are involved in the anaerobic metabolism of aromatics (toluene) and alkanes, respectively and, (ii) of genes coding for nucleotide excision repair exonucleases indicating that DNA repair processes are also activated.

  8. Influence of larval period on responses of overwintering green frog (Rana clamitans) larvae exposed to contaminated sediments

    Energy Technology Data Exchange (ETDEWEB)

    Snodgrass, J.W.; Hopkins, W.A.; Jackson, B.P.; Baionno, J.A.; Broughton, J. [Towson State University, Towson, MD (US). Dept. of Biological Science

    2005-06-01

    Pond-breeding amphibians exhibit large intra- and interspecific differences in the duration of the aquatic larval phase. In contaminated aquatic environments, a prolonged larval phase means prolonged exposure to pollutants and, potentially, more severe toxic effects. In the laboratory, we tested this hypothesis by exposing green frog larvae (Rana clamitans) to commercial clean sand (control), sediment from an abandoned surface mine (mine), or sediment contaminated with coal combustion waste (CCW). By collecting eggs late in the breeding season, we obligated larvae to overwinter and spend a protracted amount of time exposed to contaminated sediments. The experiment was continued until all larvae either successfully completed metamorphosis or died (301 d). Larvae exposed to mine sediments accumulated significant levels of Pb and Zn, whereas larvae exposed to CCW-contaminated sediment accumulated significant levels of As, Se, Sr, and V. Larvae exposed to mine sediments suffered sublethal effects in the form of reduced growth and size at metamorphosis, but the proportion of larvae successfully completing metamorphosis (93%) was the same for both control and mine treatments. In contrast, larvae exposed to CCW-contaminated sediment suffered greatly reduced survival (13%) compared to both control and mine treatments. Moreover, among larvae in the CCW treatment, the majority of mortality occurred during the latter part the overwintering period (after day 205), corresponding to the onset of metamorphosis in the controls. Our results suggest that the length of the larval period may be one of many life-history or ecological characteristics that influence the sensitivity of aquatic breeding amphibians to environmental pollutants.

  9. Local to regional scale industrial heavy metal pollution recorded in sediments of large freshwater lakes in central Europe (lakes Geneva and Lucerne) over the last centuries.

    Science.gov (United States)

    Thevenon, Florian; Graham, Neil D; Chiaradia, Massimo; Arpagaus, Philippe; Wildi, Walter; Poté, John

    2011-12-15

    This research first focuses on the spatial and temporal patterns of heavy metals from contrasting environments (highly polluted to deepwater sites) of Lake Geneva. The mercury (Hg) and lead (Pb) records from two deepwater sites show that the heavy metal variations before the industrial period are primarily linked to natural weathering input of trace elements. By opposition, the discharge of industrial treated wastewaters into Vidy Bay of Lake Geneva during the second part of the 20th century, involved the sedimentation of highly metal-contaminated sediments in the area surrounding the WWTP outlet pipe discharge. Eventually, a new Pb isotope record of sediments from Lake Lucerne identifies the long-term increasing anthropogenic lead pollution after ca. 1500, probably due to the development of metallurgical activities during the High Middle Ages. These data furthermore allows to compare the recent anthropogenic sources of water pollution from three of the largest freshwater lakes of Western Europe (lakes Geneva, Lucerne, and Constance). High increases in Pb and Hg highlight the regional impact of industrial pollution after ca. 1750-1850, and the decrease of metal pollution in the 1980s due to the effects of remediation strategies such as the implementation of wastewater treatment plants (WWTPs). However, at all the studied sites, the recent metal concentrations remain higher than pre-industrial levels. Moreover, the local scale pollution data reveal two highly contaminated sites (>100 μg Pb/g dry weight sediment) by industrial activities, during the late-19th and early-20th centuries (Lake Lucerne) and during the second part of the 20th century (Vidy Bay of Lake Geneva). Overall, the regional scale pollution history inferred from the three large and deep perialpine lakes points out at the pollution of water systems by heavy metals during the last two centuries due to the discharge of industrial effluents. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Preparation of pure phenols from tars

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, J

    1933-02-07

    A process is disclosed for the preparation of pure phenols from brown coal tar, shale tar, or primary tar, characterized in that the raw oil obtained from the tar is carefully fractionated, in a suitable way without or with a slight pressure decrease, or before the fractionation the raw oil is heated to free the prepared phenolate solution from impurities after successful oxidation by passing in steam at a temperature between 100 and 120/sup 0/C.

  11. Sediment-water distribution of contaminants of emerging concern in a mixed use watershed

    Science.gov (United States)

    This study evaluated the occurrence and distribution of 15 contaminants of emerging concern (CEC) in stream water and sediments in the Zumbro River watershed in Minnesota and compared these with sub-watershed land uses. Sixty pairs of sediment and water samples were collected across all seasons from...

  12. Analysis of tars produced in biomass gasification

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, J.; Wang, Y.; Kinoshita, C.M. [Univ. of Hawaii, Honolulu, HI (United States)

    1993-12-31

    Parametric tests on tar formation, varying temperature, equivalence ratio, and residence time, are performed on a bench-scale, indirectly-heated fluidized bed gasifier. Prepared tar samples are analyzed in a gas chromatograph (GC) with a flame ionization detector, using a capillary column. Standards containing dominant tar species have been prepared for GC calibration. The identified peaks include single-ring hydrocarbons, such as benzene, to five-ring hydrocarbons, such as perylene; depending on the gasification conditions, the identified species represent about 70 to 90% (mass basis) of the tar constituents. Under all conditions tested, benzene and naphthalene were the most dominant species. Temperature and equivalence ratio have significant effect on tar yield and tar composition. Tar yield decreases with increasing temperature or equivalence ratio. The test results suggest that lower temperature favors the formation of more aromatic tar species with diversified substituent groups, while higher temperature favors the formation of fewer aromatic tar species without substituent groups. Higher temperature or equivalence ratio favors the formation of polyaromatic compounds. Oxygen-containing compounds exist in significant quantities only at temperature below 800{degrees}C and decrease with increasing temperature, equivalence ratio, or residence time.

  13. Immobilization of lead and cadmium from aqueous solution and contaminated sediment using nano-hydroxyapatite

    International Nuclear Information System (INIS)

    Zhang Zizhong; Li Mengyan; Chen Wei; Zhu Shuzhen; Liu Nannan; Zhu Lingyan

    2010-01-01

    The effectiveness and mechanism of nano-hydroxyapatite particles (nHAp) in immobilizing Pb and Cd from aqueous solutions and contaminated sediment were investigated. The maximum sorption amount (Q max ) of Pb and Cd in aqueous solution was 1.17 and 0.57 mmol/g. The X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) surface and depth analysis indicated that dissolution-precipitation is the primary immobilization mechanism for Pb, while surface complexation and intraparticle diffusion account for Cd sequestration. Different amounts of nHAp (0-10% nHAp/dry weight) were added to the contaminated sediment. Sequential extraction showed that nHAp could effectively reduce the exchangeable fraction of Pb and Cd in the sediment and significantly reduce the concentration in porewater. The results in this study showed that nHAp can immobilize Pb and Cd in sediment effectively. - Nano-hydroxyapatite shows potential and advantages to immobilize lead and cadmium in aqueous solution and sediment.

  14. Determination of phenol in tar

    Energy Technology Data Exchange (ETDEWEB)

    Dierichs, A; Heinichen, G

    1955-01-01

    During low-temperature carbonization of lignite, the phenols and other oxygenated compounds appear both in the aqueous-process liquor and in the tar. Measurements of these oxygenated components resulting from low-temperature carbonization may serve as a parameter for the classification of lignites. However, such measurements are complicated by the instability of the tar and the complex nature of some of the acidic substances. Difficulties with the previous methods of analysis are reviewed. The present method outlines separation of aqueous-process liquor from lignite tar in a Fischer retort, followed by determination of phenols and fatty acids in the tar phase. The jacketed tar receiver is washed with 300 milliliter xylol and treated with aqueous caustic washes. Neutral oils are separated from the aqueous alkali solution. It is then extracted with ether and finally acidified with HCl. Solids are filtered off, and phenols and fatty acids are separated by Na/sub 2/CO/sub 3/ solution.

  15. Comparison of bioaccumulation and biomarker responses in Dreissena polymorpha and D. bugensis after exposure to resuspended sediments.

    Science.gov (United States)

    Schäfer, S; Hamer, B; Treursić, B; Möhlenkamp, C; Spira, D; Korlević, M; Reifferscheid, G; Claus, E

    2012-05-01

    The zebra mussel Dreissena polymorpha is widely used as sentinel organism for the assessment of environmental contamination in freshwater environments. However, in the River Rhine (Germany), the D. polymorpha population is declining, whereas the closely related quagga mussel D. bugensis is found in high numbers at some sites. In the present laboratory study, D. polymorpha and D. bugensis were exposed to resuspended native sediments for ≤2 weeks. Wet sediments (quagga mussel can be used as alternative test organism for the zebra mussel.

  16. Trace metal contamination in mangrove sediments, Guanabara Bay, Rio de Janeiro, Brazil

    OpenAIRE

    Farias,Cassia O.; Hamacher,Claudia; Wagener,Angela de Luca R.; Campos,Reinaldo C. de; Godoy,José M.

    2007-01-01

    The Guanabara Bay in Rio de Janeiro has undergone profound alterations of its natural environmental conditions. Metal concentration increase in sediments has been reported to be among these alterations. Trace-metal contamination and availability were studied in sediments of 3 mangrove areas of the bay. Cd, Zn, Pb, Ni, Cu and Al concentrations were determined in segments of sediment cores, after treatment with 1 mol L-1 HCl and with concentrated HNO3. Fe and Mn were determined in the leach wit...

  17. A marine to freshwater sediment succession from Kowhai Beach wetland, Northland : implications for Holocene sea level

    International Nuclear Information System (INIS)

    Hicks, H.; Nichol, S.L.

    2007-01-01

    An infilled wetland located behind coastal dunes in north-east Northland is used to reconstruct a local history of environmental change spanning early Holocene (c. 7000 yr BP) to modern time. Proxy indicators (sediment texture, diatoms and pollen) provide evidence for a transition from marginal marine- to brackish- to freshwater-conditions in the wetland. Radiocarbon ages constrain the chronology of this succession to 7880-7430 cal. yr BP for the early period of marine conditions, 3570-3210 cal. yr BP for the latter brackish phase and 1060-800 cal. yr BP for the change to freshwater conditions. Within this succession, the diatom record preserves a strong brackish signal at core depths above the limit of the modern tidal range. This is presented as preliminary evidence for a mid-Holocene sea level highstand for northern New Zealand of approximately 1.2 m above present mean sea level. (author). 40 refs., 7 figs., 1 tab

  18. Influence of Chironomus riparius (Diptera, Chironomidae) and Tubifex tubifex (Annelida, Oligochaeta) on oxygen uptake by sediments. Consequences of uranium contamination

    Energy Technology Data Exchange (ETDEWEB)

    Lagauzere, S. [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire (IRSN), DEI/SECRE/LRE, Cadarache 186, BP 3, F-13115 Cedex, Saint Paul Lez Durance (France)], E-mail: lagauzere@gmail.com; Pischedda, L.; Cuny, P. [Laboratoire de Microbiologie, Geochimie et Ecologie Marines, UMR 6117 CNRS/COM/Universite de la Mediterranee, Campus de Luminy, Case 901, F-13288 Cedex 09, Marseille (France); Gilbert, F. [EcoLab, Laboratoire d' Ecologie Fonctionnelle, UMR 5245 CNRS/INP/Universite Paul Sabatier, 29 Rue Jeanne Marvig, F-31055 Cedex 4, Toulouse (France); Stora, G. [Laboratoire de Microbiologie, Geochimie et Ecologie Marines, UMR 6117 CNRS/COM/Universite de la Mediterranee, Campus de Luminy, Case 901, F-13288 Cedex 09, Marseille (France); Bonzom, J.-M. [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire (IRSN), DEI/SECRE/LRE, Cadarache 186, BP 3, F-13115 Cedex, Saint Paul Lez Durance (France)

    2009-04-15

    The diffusive oxygen uptake (DOU) of sediments inhabited by Chironomus riparius and Tubifex tubifex was investigated using a planar oxygen optode device, and complemented by measurements of bioturbation activity. Additional experiments were performed within contaminated sediments to assess the impact of uranium on these processes. After 72 h, the two invertebrate species significantly increased the DOU of sediments (13-14%), and no temporal variation occurred afterwards. Within contaminated sediments, it was already 24% higher before the introduction of the organisms, suggesting that uranium modified the sediment biogeochemistry. Although the two species firstly reacted by avoidance of contaminated sediment, they finally colonized it. Their bioturbation activity was reduced but, for T. tubifex, it remained sufficient to induce a release of uranium to the water column and an increase of the DOU (53%). These results highlight the necessity of further investigations to take into account the interactions between bioturbation, microbial metabolism and pollutants. - This study highlights the ecological importance of bioturbation in metal-contaminated sediments.

  19. Influence of Chironomus riparius (Diptera, Chironomidae) and Tubifex tubifex (Annelida, Oligochaeta) on oxygen uptake by sediments. Consequences of uranium contamination

    International Nuclear Information System (INIS)

    Lagauzere, S.; Pischedda, L.; Cuny, P.; Gilbert, F.; Stora, G.; Bonzom, J.-M.

    2009-01-01

    The diffusive oxygen uptake (DOU) of sediments inhabited by Chironomus riparius and Tubifex tubifex was investigated using a planar oxygen optode device, and complemented by measurements of bioturbation activity. Additional experiments were performed within contaminated sediments to assess the impact of uranium on these processes. After 72 h, the two invertebrate species significantly increased the DOU of sediments (13-14%), and no temporal variation occurred afterwards. Within contaminated sediments, it was already 24% higher before the introduction of the organisms, suggesting that uranium modified the sediment biogeochemistry. Although the two species firstly reacted by avoidance of contaminated sediment, they finally colonized it. Their bioturbation activity was reduced but, for T. tubifex, it remained sufficient to induce a release of uranium to the water column and an increase of the DOU (53%). These results highlight the necessity of further investigations to take into account the interactions between bioturbation, microbial metabolism and pollutants. - This study highlights the ecological importance of bioturbation in metal-contaminated sediments

  20. Cytotoxicity of TiO{sub 2} nanoparticles towards freshwater sediment microorganisms at low exposure concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Kumari, Jyoti; Kumar, Deepak; Mathur, Ankita; Naseer, Arif; Kumar, Ravi Ranjan [Centre for Nanobiotechnology, VIT University, Vellore 632014 (India); Thanjavur Chandrasekaran, Prathna [Department of Materials Engineering, Indian Institute of Science, Bangalore (India); Chaudhuri, Gouri; Pulimi, Mrudula [Centre for Nanobiotechnology, VIT University, Vellore 632014 (India); Raichur, Ashok M. [Department of Materials Engineering, Indian Institute of Science, Bangalore (India); Department of Chemical Technology, University of Johannesburg (South Africa); Babu, S. [School of Bio Sciences and Technology, VIT University, Vellore (India); Chandrasekaran, Natarajan [Centre for Nanobiotechnology, VIT University, Vellore 632014 (India); Nagarajan, R. [Department of Chemical Engineering, IIT Madras, Chennai (India); Mukherjee, Amitava, E-mail: amit.mookerjea@gmail.com [Centre for Nanobiotechnology, VIT University, Vellore 632014 (India)

    2014-11-15

    There is a persistent need to assess the effects of TiO{sub 2} nanoparticles on the aquatic ecosystem owing to their increasing usage in consumer products and risk of environmental release. The current study is focused on TiO{sub 2} nanoparticle-induced acute toxicity at sub-ppm level (≤1 ppm) on the three different freshwater sediment bacterial isolates and their consortium under two different irradiation (visible light and dark) conditions. The consortium of the bacterial isolates was found to be less affected by the exposure to the nanoparticles compared to the individual cells. The oxidative stress contributed considerably towards the cytotoxicity under both light and dark conditions. A statistically significant increase in membrane permeability was noted under the dark conditions as compared to the light conditions. The optical and fluorescence microscopic images showed aggregation and chain formation of the bacterial cells, when exposed to the nanoparticles. The electron microscopic (SEM, TEM) observations suggested considerable damage of cells and bio-uptake of nanoparticles. The exopolysaccrides (EPS) production and biofilm formation were noted to increase in the presence of the nanoparticles, and expression of the key genes involved in biofilm formation was studied by RT-PCR. - Highlights: • Toxicity of NPs towards freshwater sediment bacteria at sub-ppm concentrations. • Decreased toxicity of the nanoparticles in the consortium of microorganisms. • Enhanced bacterial resistance through EPS and biofilm formation in the presence of NPs. • Considerable surface damage of cells and internalization of NPs. • Gene expression analyses related to biofilm formation in the presence of NPs.

  1. Scale-dependency of macroinvertebrate communities: responses to contaminated sediments within run-of-river dams.

    Science.gov (United States)

    Colas, Fanny; Archaimbault, Virginie; Devin, Simon

    2011-03-01

    Due to their nutrient recycling function and their importance in food-webs, macroinvertebrates are essential for the functioning of aquatic ecosystems. These organisms also constitute an important component of biodiversity. Sediment evaluation and monitoring is an essential aspect of ecosystem monitoring since sediments represent an important component of aquatic habitats and are also a potential source of contamination. In this study, we focused on macroinvertebrate communities within run-of-river dams, that are prime areas for sediment and pollutant accumulation. Little is known about littoral macroinvertebrate communities within run-of-river dam or their response to sediment levels and pollution. We therefore aimed to evaluate the following aspects: the functional and structural composition of macroinvertebrate communities in run-of-river dams; the impact of pollutant accumulation on such communities, and the most efficient scales and tools needed for the biomonitoring of contaminated sediments in such environments. Two run-of-river dams located in the French alpine area were selected and three spatial scales were examined: transversal (banks and channel), transversal x longitudinal (banks/channel x tail/middle/dam) and patch scale (erosion, sedimentation and vegetation habitats). At the patch scale, we noted that the heterogeneity of littoral habitats provided many available niches that allow for the development of diversified macroinvertebrate communities. This implies highly variable responses to contamination. Once combined on a global 'banks' spatial scale, littoral habitats can highlight the effects of toxic disturbances. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Organotin persistence in contaminated marine sediments and porewaters: In situ degradation study using species-specific stable isotopic tracers

    Energy Technology Data Exchange (ETDEWEB)

    Furdek, Martina; Mikac, Nevenka [Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, Zagreb (Croatia); Bueno, Maite; Tessier, Emmanuel; Cavalheiro, Joana [Laboratoire de Chimie Analytique Bio-inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l’Environnement et les Matériaux, CNRS UMR 5254, Université de Pau et des Pays de l’Adour, Hélioparc Pau Pyrénées, 2, Av. P. Angot, 64053 Pau Cedex 9 (France); Monperrus, Mathilde, E-mail: mathilde.monperrus@univ-pau.fr [Laboratoire de Chimie Analytique Bio-inorganique et Environnement, Institut Pluridisciplinaire de Recherche sur l’Environnement et les Matériaux, CNRS UMR 5254, Université de Pau et des Pays de l’Adour, Hélioparc Pau Pyrénées, 2, Av. P. Angot, 64053 Pau Cedex 9 (France)

    2016-04-15

    Highlights: • Limiting step in OTC degradation in sediments is their desorption into porewater. • TBT persistence in contaminated sediments increases in sediments rich in organic matter. • DBT does not accumulate in sediments as degradation product of TBT. • TBT and DBT degradation in porewaters occurs with half-lives from 2.9 to 9.2 days. • PhTs degradation is slower than BuTs degradation in oxic porewaters. - Abstract: This paper provides a comprehensive study of the persistence of butyltins and phenyltins in contaminated marine sediments and presents the first data on their degradation potentials in porewaters. The study’s aim was to explain the different degradation efficiencies of organotin compounds (OTC) in contaminated sediments. The transformation processes of OTC in sediments and porewaters were investigated in a field experiment using species-specific, isotopically enriched organotin tracers. Sediment characteristics (organic carbon content and grain size) were determined to elucidate their influence on the degradation processes. The results of this study strongly suggest that a limiting step in OTC degradation in marine sediments is their desorption into porewaters because their degradation in porewaters occurs notably fast with half-lives of 9.2 days for tributyltin (TBT) in oxic porewaters and 2.9 ± 0.1 and 9.1 ± 0.9 days for dibutyltin (DBT) in oxic and anoxic porewaters, respectively. By controlling the desorption process, organic matter influences the TBT degradation efficiency and consequently defines its persistence in contaminated sediments, which thus increases in sediments rich in organic matter.

  3. Organotin persistence in contaminated marine sediments and porewaters: In situ degradation study using species-specific stable isotopic tracers

    International Nuclear Information System (INIS)

    Furdek, Martina; Mikac, Nevenka; Bueno, Maite; Tessier, Emmanuel; Cavalheiro, Joana; Monperrus, Mathilde

    2016-01-01

    Highlights: • Limiting step in OTC degradation in sediments is their desorption into porewater. • TBT persistence in contaminated sediments increases in sediments rich in organic matter. • DBT does not accumulate in sediments as degradation product of TBT. • TBT and DBT degradation in porewaters occurs with half-lives from 2.9 to 9.2 days. • PhTs degradation is slower than BuTs degradation in oxic porewaters. - Abstract: This paper provides a comprehensive study of the persistence of butyltins and phenyltins in contaminated marine sediments and presents the first data on their degradation potentials in porewaters. The study’s aim was to explain the different degradation efficiencies of organotin compounds (OTC) in contaminated sediments. The transformation processes of OTC in sediments and porewaters were investigated in a field experiment using species-specific, isotopically enriched organotin tracers. Sediment characteristics (organic carbon content and grain size) were determined to elucidate their influence on the degradation processes. The results of this study strongly suggest that a limiting step in OTC degradation in marine sediments is their desorption into porewaters because their degradation in porewaters occurs notably fast with half-lives of 9.2 days for tributyltin (TBT) in oxic porewaters and 2.9 ± 0.1 and 9.1 ± 0.9 days for dibutyltin (DBT) in oxic and anoxic porewaters, respectively. By controlling the desorption process, organic matter influences the TBT degradation efficiency and consequently defines its persistence in contaminated sediments, which thus increases in sediments rich in organic matter.

  4. A combination of bioleaching and bioprecipitation for deep removal of contaminating metals from dredged sediment

    Energy Technology Data Exchange (ETDEWEB)

    Fang Di, E-mail: dfang@ouc.edu.cn [Department of Environmental Engineering, Ocean University of China, Qingdao 266100 (China); State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Zhang Ruichang [Department of Environmental Engineering, Ocean University of China, Qingdao 266100 (China); Zhou Lixiang [Department of Environmental Engineering, Nanjing Agricultural University, Nanjing 210095 (China); Li Jie [Department of Environmental Engineering, Ocean University of China, Qingdao 266100 (China)

    2011-08-15

    Highlights: {yields} Bioleaching-bioprecipitation can deeply cleanup sediment-borne metal contaminants. {yields} Bioleaching results in a sufficient solubilisation of sediment-borne metals. {yields} Bioprecipitation removes most of solubilised metals from sediment leachate at pH 3.7. {yields} Bioremoval of soluble Zn, Cu and Cr is due to the formation of ZnS, Cu{sub 2}S and CrOOH. {yields} Alkalization of bioleached sediment by Ca(OH){sub 2} excludes the risk of re-acidification. - Abstract: A linked microbial process comprising bioleaching with sulfate-oxidizing bacteria and bioprecipitation with sulfate-reducing bacteria operating sequentially was investigated to deeply remove contaminating metals from dredged sediment. The results showed that sediment bioleaching resulted in a sharp decrease in sediment pH from an initial pH {approx}7.6 to pH {approx}2.5 within 10-20 days, approximately 65% of the main heavy metals present (Zn + Cu + Cr) were solubilized, and most of the unsolubilized metals existed in residual form of sediment. The acidic leachate that resulted from sediment bioleaching was efficiently stripped of metal sulfates using a bioprecipitation reactor when challenged with influent as low as pH {approx}3.7. More than 99% of Zn{sup 2+}, 99% of Cu{sup 2+} and 90% of Cr{sup 3+} were removed from the leachate, respectively, due to the formation of ZnS, Cu{sub 2}S and CrOOH precipitates, as confirmed by SEM-EDS and XRD detection. It was also found that alkalization of bioleached sediment using Ca(OH){sub 2} excluded the risk of sediment re-acidification. The ability of the combined process developed in this study to deeply remove heavy metals in insoluble sulfides or hydroxides forms makes it particularly attractive for the treatment of different types of metal contaminants.

  5. A combination of bioleaching and bioprecipitation for deep removal of contaminating metals from dredged sediment

    International Nuclear Information System (INIS)

    Fang Di; Zhang Ruichang; Zhou Lixiang; Li Jie

    2011-01-01

    Highlights: → Bioleaching-bioprecipitation can deeply cleanup sediment-borne metal contaminants. → Bioleaching results in a sufficient solubilisation of sediment-borne metals. → Bioprecipitation removes most of solubilised metals from sediment leachate at pH 3.7. → Bioremoval of soluble Zn, Cu and Cr is due to the formation of ZnS, Cu 2 S and CrOOH. → Alkalization of bioleached sediment by Ca(OH) 2 excludes the risk of re-acidification. - Abstract: A linked microbial process comprising bioleaching with sulfate-oxidizing bacteria and bioprecipitation with sulfate-reducing bacteria operating sequentially was investigated to deeply remove contaminating metals from dredged sediment. The results showed that sediment bioleaching resulted in a sharp decrease in sediment pH from an initial pH ∼7.6 to pH ∼2.5 within 10-20 days, approximately 65% of the main heavy metals present (Zn + Cu + Cr) were solubilized, and most of the unsolubilized metals existed in residual form of sediment. The acidic leachate that resulted from sediment bioleaching was efficiently stripped of metal sulfates using a bioprecipitation reactor when challenged with influent as low as pH ∼3.7. More than 99% of Zn 2+ , 99% of Cu 2+ and 90% of Cr 3+ were removed from the leachate, respectively, due to the formation of ZnS, Cu 2 S and CrOOH precipitates, as confirmed by SEM-EDS and XRD detection. It was also found that alkalization of bioleached sediment using Ca(OH) 2 excluded the risk of sediment re-acidification. The ability of the combined process developed in this study to deeply remove heavy metals in insoluble sulfides or hydroxides forms makes it particularly attractive for the treatment of different types of metal contaminants.

  6. Marine sediments as a sink, and contaminated sediments as a diffuse source of radionuclides

    International Nuclear Information System (INIS)

    Salbu, B.; Borretzen, P.

    1997-01-01

    Full text: Marine sediments may act as a sink for radionuclides originating from atmospheric fallout (e.g. Chernobyl accident), for radionuclides in discharges from nuclear installations (e.g. Sellafield, UK) for river transported radionuclides, and radionuclides released from nuclear waste dumped at sea (e.g. fjords at Novaya Zemlya). In order to assess short and long term consequences of radionuclides entering the marine ecosystem, the role of sediments as a relatively permanent sink and the potential for contaminated sediments to act as a diffuse source should be focused. The retention of radionuclides in sediments will depend on the source term, i.e. the physico-chemical forms of radionuclides entering the system and on interactions with various sediment components. Radionuclides associated with particles or aggregating polymers are removed from the water phase by sedimentation, while sorption to surface sediment layers is of relevance for ionic radionuclide species including negatively charged colloids. With time, transformation processes will influence the mobility of radionuclides in sediments. The diffusion into mineral lattices will increase fixation, while the influence of for instance red/ox conditions and bio-erosion may mobilize radionuclides originally fixed in radioactive particles. Thus, information of radionuclides species, surface interactions, transformation processes and kinetics is essential for reducing the uncertainties in marine transfer models. Dynamic model experiments where chemically well defined tracers are added to a sea water-marine sediment system are useful for providing information on time dependent interactions and distribution coefficients. When combined with sequential extraction techniques, information on mobility and rate of fixation is subsequently attained. In the present work experimental results from the Irish Sea and the Kara Sea will be discussed

  7. Coal-tar-based pavement sealcoat, polycyclic aromatic Hydrocarbons (PAHs), and environmental health

    Science.gov (United States)

    Mahler, B.J.; Van Metre, P.C.

    2011-01-01

    Studies by the U.S. Geological Survey (USGS) have identified coal-tar-based sealcoat-the black, viscous liquid sprayed or painted on asphalt pavement such as parking lots-as a major source of polycyclic aromatic hydrocarbon (PAH) contamination in urban areas for large parts of the Nation. Several PAHs are suspected human carcinogens and are toxic to aquatic life.

  8. Biological treatment of PAH-contaminated sediments in a Sequencing Batch Reactor

    International Nuclear Information System (INIS)

    Chiavola, Agostina; Baciocchi, Renato; Gavasci, Renato

    2010-01-01

    The technical feasibility of a sequential batch process for the biological treatment of sediments contaminated by polycyclic aromatic hydrocarbons (PAHs) was evaluated through an experimental study. A bench-scale Sediment Slurry Sequencing Batch Reactor (SS-SBR) was fed with river sediments contaminated by a PAH mixture made by fluorene, anthracene, pyrene and crysene. The process performance was evaluated under different operating conditions, obtained by modifying the influent organic load, the feed composition and the hydraulic residence time. Measurements of the Oxygen Uptake Rates (OURs) provided useful insights on the biological kinetics occurring in the SS-SBR, suggesting the minimum applied cycle time-length of 7 days could be eventually halved, as also confirmed by the trend observed in the volatile solid and total organic carbon data. The removal efficiencies gradually improved during the SS-SBR operation, achieving at the end of the study rather constant removal rates above 80% for both 3-rings PAHs (fluorene and anthracene) and 4-ring PAHs (pyrene and crysene) for an inlet total PAH concentration of 70 mg/kg as dry weight (dw).

  9. Incorporating bioavailability into management limits for copper in sediments contaminated by antifouling paint used in aquaculture.

    Science.gov (United States)

    Simpson, Stuart L; Spadaro, David A; O'Brien, Dom

    2013-11-01

    Although now well embedded within many risk-based sediment quality guideline (SQG) frameworks, contaminant bioavailability is still often overlooked in assessment and management of contaminated sediments. To optimise management limits for metal contaminated sediments, we assess the appropriateness of a range methods for modifying SQGs based on bioavailability considerations. The impairment of reproduction of the amphipod, Melita plumulosa, and harpacticoid copepod, Nitocra spinipes, was assessed for sediments contaminated with copper from antifouling paint, located below aquaculture cages. The measurement of dilute acid-extractable copper (AE-Cu) was found to provide the most useful means for monitoring the risks posed by sediment copper and setting management limits. Acid-volatile sulfide was found to be ineffective as a SQG-modifying factor as these organisms live mostly at the more oxidised sediment water interface. SQGs normalised to %-silt/organic carbon were effective, but the benefits gained were too small to justify this approach. The effectiveness of SQGs based on AE-Cu was attributed to a small portion of the total copper being present in potentially bioavailable forms (typicallycopper was likely present as paint flakes in the form of copper (I) oxide, the active ingredient of the antifoulant formulation. While the concentrations of paint-associated copper are very high in some sediments, as the transformation of this form of copper to AE-Cu appears slow, monitoring and management limits should assess the more bioavailable AE-Cu forms, and further efforts be made to limit the release of paint particles into the environment. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  10. Composition and Dissolution of a Migratory, Weathered Coal Tar Creosote DNAPL

    Directory of Open Access Journals (Sweden)

    Kerstin E. Scherr

    2016-09-01

    Full Text Available Opaque, viscous tars derived from the carbonization of fossile carbon feedstocks, such coal tars and creosote, are long-term sources of groundwater contamination, predominantly with poly- and heterocyclic aromatic hydrocarbons (PAH. The dissolution, ageing and migratory behavior of dense, non aqueous phase liquid (DNAPL coal tar blobs and pools forming at the aquitard is not sufficiently understood to estimate the risk and adequately design groundwater treatment measures at a contaminated site. In this study, we investigate the composition and dissolution of a migrated, aged creosote DNAPL and corresponding experimental and groundwater profiles using comprehensive two-dimensional gas chromatography (GCxGC-MS. GC-FID unresolved compounds were attributed to methylated homocyclic species using GCxGC-MS in the Methylanthracene weight range. Equilibrium concentrations were estimated using Raoult’s law, assuming non-ideal behavior. Low molecular weight compounds were found to be prevalent even after decades of weathering, with Naphthalene (8% by mass representing the most abundant identified compound, contrary to the expected preferential depletion of hydrophilic compounds. Morevoer, dimethylnaphthalenes were relatively more abundant in the aqueous boundary layer than in the DNAPL. DNAPL migration over 400m with the groundwater flow effected lower viscosity and specific gravity of the migrated phase body in a superposition of weathering, transport and aquifer chromatography effects. Based on a decomposition of analysed and estimated constituents using the group contribution approach, reference DNAPL values for activity coefficients γi were used to model aqueous solubilities for selected compounds. Anthracene was close to its theoretical precipitation limit in the bulk DNAPL. While laboratory and modelled DNAPL dissolution behavior agree well, field data imply the presence of specific interfacial in situ processes significantly impacting dissolution

  11. Hydrocarbon contamination of coastal sediments from the Sfax area (Tunisia), Mediterranean Sea.

    Science.gov (United States)

    Louati, A; Elleuch, B; Kallel, M; Saliot, A; Dagaut, J; Oudot, J

    2001-06-01

    The coastal area off the city of Sfax (730,000 inhabitants), well-known for fisheries and industrial activities, receives high inputs of organic matter mostly anthropogenic. Eighteen stations were selected in the vicinity of the direct discharge of industrial sewage effluents in the sea in order to study the spatial distribution of the organic contamination. Surface sediments sampled in the shallow shelf were analysed for hydrocarbons by Fourier transform infrared spectroscopy, gas chromatography and gas chromatography/mass spectrometry. Total hydrocarbon distributions revealed high contamination as compared to other coastal Mediterranean sites, with an average concentration of 1865 ppm/dry weight sediment. Gas chromatographic distribution patterns, values of unresolved mixture/n-alkane ratio and distributions of steranes and hopanes confirmed a petroleum contamination of the Arabian light crude oil type. Biogenic compounds were also identified with a series of short-chain carbon-numbered n-alkenes in the carbon range 16-24.

  12. Hydroconversion of coal tars: effect of the temperature of pyrolysis on the reactivity of tars

    Energy Technology Data Exchange (ETDEWEB)

    Lemberton, J.L.; Touzeyidio, M.; Guisnet, M.

    1988-12-01

    The hydroconversion of a low-temperature and of a high-temperature tar was carried out in the presence of a sulfided Ni and Mo on alumina catalyst - pure or mixed with an acid catalyst (HY zeolite). Significant amounts of light products can be obtained from low temperature tar, formed however through a non-catalytic process. On the contrary, there is a slight catalytic effect during the hydroprocessing of high temperature tar, but the yield in light products is very low. These results can be explained by an extensive poisoning of the NiMo on alumina catalyst by coke which is initiated by the O- and N-containing compounds of the tars. 10 refs., 1 fig., 3 tabs.

  13. The Effect of Substrate Contaminates on the Life of Epoxy Coatings Submerged in Sea Water

    Science.gov (United States)

    1991-03-01

    contaminants: coal tar, SovaPon, Mare Island and Aquapon . Aquapon is a clear (unpigmented) polyamide epoxy coating. While Aquapon is not normally used for...pigmented coatings. It was found that the Aquapon and coal tar coatings performed similarly, and blistered to the same extent, at the contamination levels...used in the test program. The Sovapon and Mare Island coatings were slightly more resistive to blistering when compared to Aquapon or coal tar but they

  14. Natural attenuation of aged tar-oil in soils: A case study from a former gas production site

    Science.gov (United States)

    Ivanov, Pavel; Eickhorst, Thilo; Wehrer, Markus; Georgiadis, Anna; Rennert, Thilo; Eusterhues, Karin; Totsche, Kai Uwe

    2017-04-01

    Contamination of soils with tar oil occurred on many industrial sites in Europe. The main source of such contamination has been former manufactured gas plants (MGP). As many of them were destroyed during the World War II or abandoned in the second half of the XXth century, the contamination is depleted in volatile and degradable hydrocarbons (HC) but enriched in the heavy oil fractions due to aging processes. We studied a small tar-oil spill in a former MGP reservoir basin. The tar-oil had a total petroleum hydrocarbon (TPH) content of 245 mg/g. At the margin of the spill, vegetation has started to overgrow and intensively root the tar-oil layer. This zone comprised the uppermost 5-7 cm of our profile and contained 28 mg/g of TPH (A-layer)- The layer below the root zone (7-15 cm) was the most contaminated, with 90 mg/g TPH (B-layer). The layer underneath (15-22 cm) had smaller concentrations of 16 mg/g TPH (C-layer). Further down in the profile (D-layer) we found only slightly higher TPH content than in the control samples (1,4 mg/g vs 0,6 mg/g). The polycyclic aromatic hydrocarbons analysis showed the same distribution throughout all layers with highest contents of the PAHs with 4-6 condensed aromatic rings. Direct cell count and extraction of microbial biomass showed that the highly contaminated soil layers A and B had 2-3 times more bacteria than the control soils. CARD-FISH analysis revealed that in samples from layers A and B Archaea were more abundant (12% opposing to 6-7% in control soil). Analysis of bacteria (tested for Alpha-, Beta-, Gamma- and Epsilonproteobacteria and Actinobacteria) showed the dominance of Alphaproteobacteria in the layer A and C both beneath and above the most contaminated layer B. The primers covered the whole microbial consortia in these two layers, leaving almost no unidentified cells. In the most contaminated layer B Alphaproteobacteria amounted only to 20% of the microbial consortium, and almost 40% of the cells remained

  15. Different partition of polycyclic aromatic hydrocarbon on environmental particulates in freshwater: Microplastics in comparison to natural sediment.

    Science.gov (United States)

    Wang, Wenfeng; Wang, Jun

    2018-01-01

    Microplastics pollution in the aquatic ecosystems has aroused increasing concerns in recent years. Though microplastics are known to sorb organic contaminants from water, the interaction mechanisms between microplastics and organic chemicals are not yet well understood. Here we investigated the partition characteristics of phenanthrene (Phe) in three mass-produced plastic particles, including polyethylene (PE), polystyrene (PS) and polyvinylchloride (PVC), and one natural sediment, as a comparison. The sorption kinetics of Phe onto microplastics and natural sediment were successfully described by the pseudo-second-order model (R 2 > 0.992), while the equilibrium data were best-fitted to the Langmuir isotherm (R 2 > 0.995). Compared with natural sediment, microplastics exhibited higher capacities for Phe which followed an order of PE > PS > PVC. As the aqueous concentration of pyrene (Pyr) increased, both uptakes and distribution coefficients (K d ) of Phe within the solids decreased, with natural sediment giving the largest decline. Although proportions of Phe desorbed from the contaminated microplastics were low, due to the high Phe uptake, microplastics released larger amounts of the sorbed Phe to water than the natural sediment during the desorption process. Given their minimal abundance relative to natural sediment, microplastics may play a less important role in the transport of organic pollutants in a natural aquatic environment. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Quantitative analysis of the extent of heavy-metal contamination in soils near Picher, Oklahoma, within the Tar Creek Superfund Site.

    Science.gov (United States)

    Beattie, Rachelle E; Henke, Wyatt; Davis, Conor; Mottaleb, M Abdul; Campbell, James H; McAliley, L Rex

    2017-04-01

    The Tri-State Mining District of Missouri, Kansas and Oklahoma was the site of large-scale mining operations primarily for lead and zinc until the mid-1950s. Although mining across the area has ceased, high concentrations of heavy metals remain in the region's soil and water systems. The town of Picher, Ottawa County, OK, lies within this district and was included in the Tar Creek Superfund Site by the U.S. Environmental Protection Agency in 1980 due to extensive contamination. To elucidate the extent of heavy-metal contamination, a soil-chemistry survey of the town of Picher was conducted. Samples (n = 111) were collected from mine tailings, locally known as chat, in Picher and along cardinal-direction transects within an 8.05-km radius of the town in August 2015. Samples were analyzed for soil pH, moisture, and metal content. Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) analyses of 20 metals showed high concentrations of lead (>1000 ppm), cadmium (>40 ppm) and zinc (>4000 ppm) throughout the sampled region. Soil moisture content ranged from 0.30 to 35.9%, and pH values ranged from 5.14 to 7.42. MANOVA of metal profiles determined that soils collected from the north transect and chat were significantly different (p zinc were correlated with one another. These data show an unequal distribution of contamination surrounding the Picher mining site. Mapping heavy-metal contamination in these soils represents the first step in understanding the distribution of these contaminants at the Picher mining site. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Trace metal distribution in sediments of the Pearl River Estuary and the surrounding coastal area, South China

    International Nuclear Information System (INIS)

    Ip, Carman C.M.; Li Xiangdong; Zhang Gan; Wai, Onyx W.H.; Li, Y.-S.

    2007-01-01

    Surface sediments and sediment cores collected at the Pearl River Estuary (PRE) and its surrounding coastal area were analysed for total metal concentrations, chemical partitioning, and Pb isotopic compositions. The distribution of Cu, Cr, Pb, and Zn demonstrated a typical diffusion pattern from the land to the direction of the sea. Two hotspots of trace metal contamination were located at the mixed zone between freshwater and marine waters. The enrichment of metals in the sediments could be attributed to the deposition of the dissolved and particulate trace metals in the water column at the estuarine area. The similar Pb isotopic signatures of the sediments at the PRE and its surrounding coastal area offered strong evidence that the PRE was a major source of trace metals to the adjacent coastal area. Slightly lower 206 Pb/ 207 Pb ratios in the coastal sediments may indicate other inputs of Pb in addition to the PRE sources, including the inputs from Hong Kong and other parts of the region. - The distribution of trace metals in sediments reflected contaminant sources, physical and chemical deposition processes

  18. Assimilation of remote sensing observations into a sediment transport model of China's largest freshwater lake: spatial and temporal effects.

    Science.gov (United States)

    Zhang, Peng; Chen, Xiaoling; Lu, Jianzhong; Zhang, Wei

    2015-12-01

    Numerical models are important tools that are used in studies of sediment dynamics in inland and coastal waters, and these models can now benefit from the use of integrated remote sensing observations. This study explores a scheme for assimilating remotely sensed suspended sediment (from charge-coupled device (CCD) images obtained from the Huanjing (HJ) satellite) into a two-dimensional sediment transport model of Poyang Lake, the largest freshwater lake in China. Optimal interpolation is used as the assimilation method, and model predictions are obtained by combining four remote sensing images. The parameters for optimal interpolation are determined through a series of assimilation experiments evaluating the sediment predictions based on field measurements. The model with assimilation of remotely sensed sediment reduces the root-mean-square error of the predicted sediment concentrations by 39.4% relative to the model without assimilation, demonstrating the effectiveness of the assimilation scheme. The spatial effect of assimilation is explored by comparing model predictions with remotely sensed sediment, revealing that the model with assimilation generates reasonable spatial distribution patterns of suspended sediment. The temporal effect of assimilation on the model's predictive capabilities varies spatially, with an average temporal effect of approximately 10.8 days. The current velocities which dominate the rate and direction of sediment transport most likely result in spatial differences in the temporal effect of assimilation on model predictions.

  19. Effectiveness of remediation of metal-contaminated mangrove sediments (Sydney estuary, Australia).

    Science.gov (United States)

    Birch, Gavin; Nath, Bibhash; Chaudhuri, Punarbasu

    2015-04-01

    Industrial activities and urbanization have had a major consequence for estuarine ecosystem health and water quality globally. Likewise, Sydney estuary has been significantly impacted by widespread, poor industrial practices in the past, and remediation of legacy contaminants have been undertaken in limited parts of this waterway. The objective of the present investigation was to determine the effectiveness of remediation of a former Pb-contaminated industrial site in Homebush Bay on Sydney estuary (Australia) through sampling of inter-tidal sediments and mangrove (Avicennia marina) tissue (fine nutritive roots, pneumatophores, and leaves). Results indicate that since remediation 6 years previously, Pb and other metals (Cu, Ni and Zn) in surficial sediment have increased to concentrations that approach pre-remediation levels and that they were considerably higher than pre-settlement levels (3-30 times), as well as at the reference site. Most metals were compartmentalized in fine nutritive roots with bio-concentration factors greater than unity, while tissues of pneumatophores and leaves contained low metal concentrations. Lead concentrations in fine nutritive root, pneumatophore, and leaf tissue of mangroves from the remediated site were similar to trees in un-remediated sites of the estuary and were substantially higher than plants at the reference site. The situation for Zn in fine nutritive root tissue was similar. The source of the metals was either surface/subsurface water from the catchment or more likely remobilized contaminated sediment from un-remediated parts of Homebush Bay. Results of this study demonstrate the problems facing management in attempting to reduce contamination in small parts of a large impacted area to concentrations below local base level.

  20. Final Project Report: Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

    Energy Technology Data Exchange (ETDEWEB)

    Jon Chorover, University of Arizona; Peggy O' €™Day, University of California, Merced; Karl Mueller, Penn State University; Wooyong Um, Pacific Northwest National Laboratory; Carl Steefel, Lawrence Berkeley National Laboratory

    2012-10-01

    Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided detailed characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, PCO2, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions.

  1. Dehydration of hydrated low-temperature tar

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, T

    1949-01-01

    Yoshida examined the mechanism of the dehydration of hydrated low-temperature tar with a microscope. The tar containing free carbon and coal dust is so stable that the removal of the above substances and water by a physical method is very difficult. Addition of light oil produced by fractionation of low-temperature tar facilitates the operations. Yoshida tried using the separate acid, neutral, and basic components of the light oil; the acid oil proved to be most effective. For many reasons it is convenient to use light oil as it is. In this method the quantity of light oil required is 2 to 3 times that of tar. But in supplementing the centrifugal method, the quantity of light oil needed might be only half the amount of tar.

  2. Enhanced bioremediation of 4-nonylphenol and cadmium co-contaminated sediment by composting with Phanerochaete chrysosporium inocula.

    Science.gov (United States)

    Xu, Piao; Lai, Cui; Zeng, Guangming; Huang, Danlian; Chen, Ming; Song, Biao; Peng, Xin; Wan, Jia; Hu, Liang; Duan, Abing; Tang, Wangwang

    2018-02-01

    Composting is identified as an effective approach for solid waste disposal. The bioremediation of 4-nonylphenol (4NP) and cadmium (Cd) co-contaminated sediment was investigated by composting with Phanerochaete chrysosporium (P. chrysosporium) inocula. P. chrysosporium inocula and proper C/N ratios (25.51) accelerated the composting process accompanied with faster total organic carbon loss, 4NP degradation and Cd passivation. Microbiological analysis demonstrated that elevated activities of lignocellulolytic enzymes and sediment enzymes was conducive to organic chemical transformation. Bacterial community diversity results illustrated that Firmicutes and Proteobacteria were predominant species during the whole composting process. Aerobic cellulolytic bacteria and organic degrading species played significant roles. Toxicity characteristic leaching procedure (TCLP) extraction and germination indices results indicated the efficient detoxification of 4NP and Cd co-contaminated sediment after 120 days of composting. Overall, results demonstrated that P. chrysosporium enhanced composting was available for the bioremediation of 4NP and Cd co-contaminated sediment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Source apportionment of trace metals in river sediments: A comparison of three methods

    International Nuclear Information System (INIS)

    Chen, Haiyang; Teng, Yanguo; Li, Jiao; Wu, Jin; Wang, Jinsheng

    2016-01-01

    Increasing trace metal pollution in river sediment poses a significant threat to watershed ecosystem health. Identifying potential sources of sediment metals and apportioning their contributions are of key importance for proposing prevention and control strategies of river pollution. In this study, three advanced multivariate receptor models, factor analysis with nonnegative constraints (FA-NNC), positive matrix factorization (PMF), and multivariate curve resolution weighted-alternating least-squares (MCR-WALS), were comparatively employed for source apportionment of trace metals in river sediments and applied to the Le'an River, a main tributary of Poyang Lake which is the largest freshwater lake in China. The pollution assessment with contamination factor and geoaccumulation index suggested that the river sediments in Le'an River were contaminated severely by trace metals due to human activities. With the three apportionment tools, similar source profiles of trace metals in sediments were extracted. Especially, the MCR-WALS and PMF models produced essentially the same results. Comparatively speaking, the weighted schemes might give better solutions than the unweighted FA-NNC because the uncertainty information of environmental data was considered by PMF and MCR-WALS. Anthropogenic sources were apportioned as the most important pollution sources influencing the sediment metals in Le'an River with contributions of about 90%. Among them, copper tailings occupied the largest contribution (38.4–42.2%), followed by mining wastewater (29.0–33.5%), and agricultural activities (18.2–18.7%). To protect the ecosystem of Le'an River and Poyang Lake, special attention should be paid to the discharges of mining wastewater and the leachates of copper tailing ponds in that region. - Highlights: • Three advanced receptor models were comparatively employed for source apportionment. • The MCR-WALS and PMF models produce essentially same source profiles. • Copper

  4. Annual sediment flux estimates in a tidal strait using surrogate measurements

    Science.gov (United States)

    Ganju, N.K.; Schoellhamer, D.H.

    2006-01-01

    Annual suspended-sediment flux estimates through Carquinez Strait (the seaward boundary of Suisun Bay, California) are provided based on surrogate measurements for advective, dispersive, and Stokes drift flux. The surrogates are landward watershed discharge, suspended-sediment concentration at one location in the Strait, and the longitudinal salinity gradient. The first two surrogates substitute for tidally averaged discharge and velocity-weighted suspended-sediment concentration in the Strait, thereby providing advective flux estimates, while Stokes drift is estimated with suspended-sediment concentration alone. Dispersive flux is estimated using the product of longitudinal salinity gradient and the root-mean-square value of velocity-weighted suspended-sediment concentration as an added surrogate variable. Cross-sectional measurements validated the use of surrogates during the monitoring period. During high freshwater flow advective and dispersive flux were in the seaward direction, while landward dispersive flux dominated and advective flux approached zero during low freshwater flow. Stokes drift flux was consistently in the landward direction. Wetter than average years led to net export from Suisun Bay, while dry years led to net sediment import. Relatively low watershed sediment fluxes to Suisun Bay contribute to net export during the wet season, while gravitational circulation in Carquinez Strait and higher suspended-sediment concentrations in San Pablo Bay (seaward end of Carquinez Strait) are responsible for the net import of sediment during the dry season. Annual predictions of suspended-sediment fluxes, using these methods, will allow for a sediment budget for Suisun Bay, which has implications for marsh restoration and nutrient/contaminant transport. These methods also provide a general framework for estimating sediment fluxes in estuarine environments, where temporal and spatial variability of transport are large. ?? 2006 Elsevier Ltd. All rights

  5. Separating cresote from tars, mineral oils, etc

    Energy Technology Data Exchange (ETDEWEB)

    Erdmann, E

    1921-01-07

    Phenolic bodies are extracted from tars such as lignite, shale, peat, coal, producer and low temperature tars, and from tar distillates and residues and from mineral oils and distillates by washing with a mixture of acetone and water. Acetone extracts of the tars etc., may be mixed with water or aqueous acetone to cause the separation of the oils, while the creosote remains in solution.

  6. Local to regional scale industrial heavy metal pollution recorded in sediments of large freshwater lakes in central Europe (lakes Geneva and Lucerne) over the last centuries

    Energy Technology Data Exchange (ETDEWEB)

    Thevenon, Florian, E-mail: Florian.Thevenon@yahoo.fr [Institute F.-A. Forel, University of Geneva, Versoix (Switzerland); Graham, Neil D. [Institute F.-A. Forel, University of Geneva, Versoix (Switzerland); Chiaradia, Massimo [Department of Mineralogy, University of Geneva, Geneva (Switzerland); Arpagaus, Philippe; Wildi, Walter; Pote, John [Institute F.-A. Forel, University of Geneva, Versoix (Switzerland)

    2011-12-15

    This research first focuses on the spatial and temporal patterns of heavy metals from contrasting environments (highly polluted to deepwater sites) of Lake Geneva. The mercury (Hg) and lead (Pb) records from two deepwater sites show that the heavy metal variations before the industrial period are primarily linked to natural weathering input of trace elements. By opposition, the discharge of industrial treated wastewaters into Vidy Bay of Lake Geneva during the second part of the 20th century, involved the sedimentation of highly metal-contaminated sediments in the area surrounding the WWTP outlet pipe discharge. Eventually, a new Pb isotope record of sediments from Lake Lucerne identifies the long-term increasing anthropogenic lead pollution after ca. 1500, probably due to the development of metallurgical activities during the High Middle Ages. These data furthermore allows to compare the recent anthropogenic sources of water pollution from three of the largest freshwater lakes of Western Europe (lakes Geneva, Lucerne, and Constance). High increases in Pb and Hg highlight the regional impact of industrial pollution after ca. 1750-1850, and the decrease of metal pollution in the 1980s due to the effects of remediation strategies such as the implementation of wastewater treatment plants (WWTPs). However, at all the studied sites, the recent metal concentrations remain higher than pre-industrial levels. Moreover, the local scale pollution data reveal two highly contaminated sites (> 100 {mu}g Pb/g dry weight sediment) by industrial activities, during the late-19th and early-20th centuries (Lake Lucerne) and during the second part of the 20th century (Vidy Bay of Lake Geneva). Overall, the regional scale pollution history inferred from the three large and deep perialpine lakes points out at the pollution of water systems by heavy metals during the last two centuries due to the discharge of industrial effluents. Highlights: Black-Right-Pointing-Pointer Natural sources

  7. Trace metals in water and sediments from Ologe Lagoon, southwestern Nigeria

    International Nuclear Information System (INIS)

    Yusuf, K.A.; Osibanjo, O.

    2006-01-01

    The concentrations of trace metals in water and sediment samples from Ologe lagoon located in southwestern Nigeria were investigated. The lagoon is a source of water for domestic, transportation and fishing activities. The water quality characteristics for a period of two years (January, 1997 - November, 1998), and the speciation of metals in the lagoon sediments were evaluated. The lagoon water quality characteristics, with respect to heavy metal contamination, were compared with global averages for freshwater and international water quality standards for drinking water. All elements except iron, were well within the safety limits. Sequential extraction techniques were used to establish the association of the total concentrations of Zn, Cu, Pb, Cd and Mn in the sediment samples with their contents as exchangeable, carbonates, Fe/Mn oxides, and organic and residual fractions. The concentrations of trace metals in the whole sediments were generally below the world-wide background levels. When compared to a number of sediment quality guidelines, the concentrations of trace metals were found to be below the level considered to have the potential to cause biological effects. Pb and Cd were extracted from the residual fraction at values greater than 50%. The metals that were most easily extractable in the samples analyzed were Mn and Zn, which posed the highest risk to water contamination. The low level of industrialization in the study area has kept the lagoon relatively free from heavy metal contamination. (author)

  8. Passive sampling methods for contaminated sediments: Scientific rationale supporting use of freely dissolved concentrations

    DEFF Research Database (Denmark)

    Mayer, Philipp; Parkerton, Thomas F.; Adams, Rachel G.

    2014-01-01

    Passive sampling methods (PSMs) allow the quantification of the freely dissolved concentration (Cfree ) of an organic contaminant even in complex matrices such as sediments. Cfree is directly related to a contaminant's chemical activity, which drives spontaneous processes including diffusive upta...

  9. Measuring hypoxia induced metal release from highly contaminated estuarine sediments during a 40 day laboratory incubation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Banks, Joanne L., E-mail: jlbanks@student.unimelb.edu.au [Department of Zoology, University of Melbourne, Victoria, 3010 Australia (Australia); Ross, D. Jeff, E-mail: Jeff.Ross@utas.edu.au [Institute of Marine and Antarctic Studies, Nubeena Crescent, Taroona, Tasmania, 7053 Australia (Australia); Keough, Michael J., E-mail: mjkeough@unimelb.edu.au [Department of Zoology, University of Melbourne, Victoria, 3010 Australia (Australia); Eyre, Bradley D., E-mail: bradley.eyre@scu.edu.au [Centre for Coastal Biogeochemistry, School of Environmental Science and Management, Southern Cross University, PO Box 157, Lismore, NSW, 2480 Australia (Australia); Macleod, Catriona K., E-mail: Catriona.Macleod@utas.edu.au [Institute of Marine and Antarctic Studies, Nubeena Crescent, Taroona, Tasmania, 7053 Australia (Australia)

    2012-03-15

    Nutrient inputs to estuarine and coastal waters worldwide are increasing and this in turn is increasing the prevalence of eutrophication and hypoxic and anoxic episodes in these systems. Many urbanised estuaries are also subject to high levels of anthropogenic metal contamination. Environmental O{sub 2} levels may influence whether sediments act as sinks or sources of metals. In this study we investigated the effect of an extended O{sub 2} depletion event (40 days) on fluxes of trace metals (and the metalloid As) across the sediment-water interface in sediments from a highly metal contaminated estuary in S.E. Tasmania, Australia. We collected sediments from three sites that spanned a range of contamination and measured total metal concentration in the overlying water using sealed core incubations. Manganese and iron, which are known to regulate the release of other divalent cations from sub-oxic sediments, were released from sediments at all sites as hypoxia developed. In contrast, the release of arsenic, cadmium, copper and zinc was comparatively low, most likely due to inherent stability of these elements within the sediments, perhaps as a result of their refractory origin, their association with fine-grained sediments or their being bound in stable sulphide complexes. Metal release was not sustained due to the powerful effect of metal-sulphide precipitation of dissolved metals back into sediments. The limited mobilisation of sediment bound metals during hypoxia is encouraging, nevertheless the results highlight particular problems for management in areas where hypoxia might occur, such as the release of metals exacerbating already high loads or resulting in localised toxicity. - Highlights: Black-Right-Pointing-Pointer Metal contaminated sediments exposed to long-term hypoxia released Mn and Fe pulses. Black-Right-Pointing-Pointer As flux increased under anoxic conditions Cd, Cu and Zn fluxes occurred only during the first week of hypoxia. Black

  10. Mathematical simulation of sediment and contaminant transport in surface waters. Annual report, October 1977--September 1978

    International Nuclear Information System (INIS)

    Onishi, Y.; Arnold, E.M.; Serne, R.J.; Cowan, C.E.; Thompson, F.L.; Mayer, D.W.

    1979-01-01

    Various pathways exist for exposure of humans and biota to radioactive materials released from nuclear facilities. Hydrologic transport (liquid pathway) is one element in the evaluation of the total radiation dose to man. Mathematical models supported by well-planned field data collection programs can be useful tools in assessing the hydrologic transport and ultimate fate of radionuclides. Radionuclides with high distribution coefficients or radionuclides in surface waters with high suspended sediment concentrations are, to a great extent, adsorbed by river and marine sediments. Thus, otherwise dilute contaminants are concentrated. Contaminated sediments may be deposited on the river and ocean beds creating a significant pathway to man. Contaminated bed sediment in turn may become a long-term source of pollution through desorption and resuspension. In order to assess migration and accumulation of radionuclides in surface waters, mathematical models must correctly simulate essential mechanisms of radionuclide transport. The objectives of this study were: (1) to conduct a critical review of (a) radionuclide transport models as well as sediment transport and representative water quality models in rivers, estuaries, oceans, lakes, and reservoirs, and (b) adsorption and desorption mechanisms of radionuclides with sediments in surface waters; (2) to synthesize a mathematical model capable of predicting short- and long-term transport and accumulation of radionuclides in marine environments

  11. Effects of lead-contaminated sediment on Rana sphenocephala tadpoles

    Science.gov (United States)

    Sparling, D.W.; Krest, S.K.; Ortiz-Santaliestra, M.

    2006-01-01

    We exposed larval southern leopard frogs (Rana sphenocephala) to lead-contaminated sediments to determine the lethal and sublethal effects of this metal. Tadpoles were laboratory-raised from early free-swimming stage through metamorphosis at lead concentrations of 45, 75, 180, 540, 2360, 3940, 5520, and 7580 mg/kg dry weight in sediment. Corresponding pore water lead concentrations were 123, 227, 589, 1833, 8121, 13,579, 19,038, and 24,427 ug/L. Tadpoles exposed to lead concentrations in sediment of 3940 mg/kg or higher died within 2 to 5 days of exposure. At lower concentrations, mortality through metamorphosis ranged from 3.5% at 45 mg/kg lead to 37% at 2360 mg/kg lead in sediment. The LC50 value for lead in sediment was 3728 mg/kg (95% CI=1315 to 72,847 mg/kg), which corresponded to 12,539 ug/L lead in pore water (95% CI= 4000 to 35,200 ug/L). Early growth and development were depressed at 2,360 mg/kg lead in sediment (8100 ug/L in pore water) but differences were not evident by the time of metamorphosis. The most obvious effect of lead was its pronounced influence on skeletal development. Whereas tadpoles at 45 mg/kg lead in sediment did not display permanent abnormalities, skeletal malformations increased in frequency and severity at all higher lead concentrations. By 2360 mg/kg, 100% of surviving metamorphs displayed severe spinal problems, reduced femur and humerus lengths, deformed digits, and other bone malformations. Lead concentrations in tissues correlated positively with sediment and pore water concentrations.

  12. EFFECT OF CONTAMINANT AND ORGANIC MATTER BIOAVAILABILITY ON THE MICROBIAL DEHALOGENATION OF SEDIMENT-BOUND CHLOROBENZENES. (R825513C007)

    Science.gov (United States)

    The extent of reductive dechlorination occurring in contaminated, estuarine sediments was investigated. Contaminant and organic matter bioavailability and their effect on the reductive dechlorination of sediment-bound chlorobenzenes was the main focus of the work presented her...

  13. Influence of Contact Time on the Extraction of 233Uranyl Spike and Contaminant Uranium From Hanford Sediment

    International Nuclear Information System (INIS)

    Smith, Steven C.; Szecsody, James E.

    2011-01-01

    In this study 233Uranyl nitrate was added to uranium (U) contaminated Hanford 300 Area sediment and incubated under moist conditions for 1 year. It hypothesized that geochemical transformations and/or physical processes will result in decreased extractability of 233U as the incubation period increases, and eventually the extraction behavior of the 233U spike will be congruent to contaminant U that has been associated with sediment for decades. Following 1 week, 1 month, and 1 year incubation periods, sediment extractions were performed using either batch or dynamic (sediment column flow) chemical extraction techniques. Overall, extraction of U from sediment using batch extraction was less complicated to conduct compared to dynamic extraction, but dynamic extraction could distinguish the range of U forms associated with sediment which are eluted at different times.

  14. REMOTE SENSING OF THE SEDIMENTATION PLUME OF THE RIVER SAN JUAN

    OpenAIRE

    Ballestero, Daniel

    2004-01-01

    The River San Juan (RSJ), in the border between Nicaragua and Costa Rica, is one the major rivers in Central America and drains the largest basin in the region (38570 km²) in terms of volume. Extending from Lago Cicibolca to the Caribbean Sea, the RSJ is an important source of freshwater, sediments, nutrients and pollutants to the continental shelf. Ecosystems degradation, contamination of water bodies and overexploitation of natural resources, particularly deforestation in the southern part ...

  15. Microbial community responses to organophosphate substrate additions in contaminated subsurface sediments.

    Directory of Open Access Journals (Sweden)

    Robert J Martinez

    Full Text Available BACKGROUND: Radionuclide- and heavy metal-contaminated subsurface sediments remain a legacy of Cold War nuclear weapons research and recent nuclear power plant failures. Within such contaminated sediments, remediation activities are necessary to mitigate groundwater contamination. A promising approach makes use of extant microbial communities capable of hydrolyzing organophosphate substrates to promote mineralization of soluble contaminants within deep subsurface environments. METHODOLOGY/PRINCIPAL FINDINGS: Uranium-contaminated sediments from the U.S. Department of Energy Oak Ridge Field Research Center (ORFRC Area 2 site were used in slurry experiments to identify microbial communities involved in hydrolysis of 10 mM organophosphate amendments [i.e., glycerol-2-phosphate (G2P or glycerol-3-phosphate (G3P] in synthetic groundwater at pH 5.5 and pH 6.8. Following 36 day (G2P and 20 day (G3P amended treatments, maximum phosphate (PO4(3- concentrations of 4.8 mM and 8.9 mM were measured, respectively. Use of the PhyloChip 16S rRNA microarray identified 2,120 archaeal and bacterial taxa representing 46 phyla, 66 classes, 110 orders, and 186 families among all treatments. Measures of archaeal and bacterial richness were lowest under G2P (pH 5.5 treatments and greatest with G3P (pH 6.8 treatments. Members of the phyla Crenarchaeota, Euryarchaeota, Bacteroidetes, and Proteobacteria demonstrated the greatest enrichment in response to organophosphate amendments and the OTUs that increased in relative abundance by 2-fold or greater accounted for 9%-50% and 3%-17% of total detected Archaea and Bacteria, respectively. CONCLUSIONS/SIGNIFICANCE: This work provided a characterization of the distinct ORFRC subsurface microbial communities that contributed to increased concentrations of extracellular phosphate via hydrolysis of organophosphate substrate amendments. Within subsurface environments that are not ideal for reductive precipitation of uranium

  16. Quantifying modern erosion rates and river-sediment contamination in the Bolivian Andes

    Science.gov (United States)

    Vezzoli, Giovanni; Ghielmi, Giacomo; Mondaca, Gonzalo; Resentini, Alberto; Villarroel, Elena Katia; Padoan, Marta; Gentile, Paolo

    2013-08-01

    We use petrographic, mineralogical and geochemical data on modern river sediments of the Tupiza basin in the Bolivian Andes to investigate the relationships among human activity, heavy-metal contamination of sediments and modern erosion rates in mountain fluvial systems. Forward mixing model was used to quantify the relative contributions from each main tributary to total sediment load of the Tupiza River. The absolute sediment load was estimated by using the Pacific Southwest Inter Agency Committee model (PSIAC, 1968) after two years of geological field surveys (2009; 2010), together with data obtained from the Instituto Nacional del Agua public authority (INA, 2007), and suspended-load data from Aalto et al. (2006). Our results indicate that the sediment yield in the drainage basin is 910 ± 752 ton/km2year and the mean erosion rate is 0.40 ± 0.33 mm/year. These values compare well with erosion rates measured by Insel et al. (2010) using 10Be cosmogenic radionuclide concentrations in Bolivian river sediments. More than 40% of the Tupiza river load is produced in the upper part of the catchment, where highly tectonized and weathered rocks are exposed and coupled with sporadic land cover and intense human activity (mines). In the Rio Chilco basin strong erosion of upland valleys produce an increase of erosion (˜10 mm/year) and the influx of large amounts of sediment by mass wasting processes. The main floodplain of the Tupiza catchment represents a significant storage site for the heavy metals (˜657 ton/year). Fluvial sediments contain zinc, lead, vanadium, chromium, arsenic and nickel. Since the residence time of these contaminants in the alluvial plain may be more than 100 years, they may represent a potential source of pollution for human health.

  17. Biogeochemical gradients above a coal tar DNAPL

    Energy Technology Data Exchange (ETDEWEB)

    Scherr, Kerstin E., E-mail: kerstin.brandstaetter-scherr@boku.ac.at [University of Natural Resources and Life Sciences Vienna (BOKU), Department IFA-Tulln, Institute for Environmental Biotechnology, Konrad Lorenz Strasse 20, 3430 Tulln (Austria); Backes, Diana [University of Natural Resources and Life Sciences Vienna (BOKU), Department IFA-Tulln, Institute for Environmental Biotechnology, Konrad Lorenz Strasse 20, 3430 Tulln (Austria); Scarlett, Alan G. [University of Plymouth, Petroleum and Environmental Geochemistry Group, Biogeochemistry Research Centre, Drake Circus, Plymouth, Devon PL4 8AA (United Kingdom); Lantschbauer, Wolfgang [Government of Upper Austria, Directorate for Environment and Water Management, Division for Environmental Protection, Kärntner Strasse 10-12, 4021 Linz (Austria); Nahold, Manfred [GUT Gruppe Umwelt und Technik GmbH, Ingenieurbüro für Technischen Umweltschutz, Plesching 15, 4040 Linz (Austria)

    2016-09-01

    Naturally occurring distribution and attenuation processes can keep hydrocarbon emissions from dense non aqueous phase liquids (DNAPL) into the adjacent groundwater at a minimum. In a historically coal tar DNAPL-impacted site, the de facto absence of a plume sparked investigations regarding the character of natural attenuation and DNAPL resolubilization processes at the site. Steep vertical gradients of polycyclic aromatic hydrocarbons, microbial community composition, secondary water quality and redox-parameters were found to occur between the DNAPL-proximal and shallow waters. While methanogenic and mixed-electron acceptor conditions prevailed close to the DNAPL, aerobic conditions and very low dissolved contaminant concentrations were identified in three meters vertical distance from the phase. Comprehensive two-dimensional gas chromatography–mass spectrometry (GC × GC–MS) proved to be an efficient tool to characterize the behavior of the present complex contaminant mixture. Medium to low bioavailability of ferric iron and manganese oxides of aquifer samples was detected via incubation with Shewanella alga and evidence for iron and manganese reduction was collected. In contrast, 16S rDNA phylogenetic analysis revealed the absence of common iron reducing bacteria. Aerobic hydrocarbon degraders were abundant in shallow horizons, while nitrate reducers were dominating in deeper aquifer regions, in addition to a low relative abundance of methanogenic archaea. Partial Least Squares – Canonical Correspondence Analysis (PLS-CCA) suggested that nitrate and oxygen concentrations had the greatest impact on aquifer community structure in on- and offsite wells, which had a similarly high biodiversity (H’ and Chao1). Overall, slow hydrocarbon dissolution from the DNAPL appears to dominate natural attenuation processes. This site may serve as a model for developing legal and technical strategies for the treatment of DNAPL-impacted sites where contaminant plumes are

  18. Measuring hypoxia induced metal release from highly contaminated estuarine sediments during a 40 day laboratory incubation experiment

    International Nuclear Information System (INIS)

    Banks, Joanne L.; Ross, D. Jeff; Keough, Michael J.; Eyre, Bradley D.; Macleod, Catriona K.

    2012-01-01

    Nutrient inputs to estuarine and coastal waters worldwide are increasing and this in turn is increasing the prevalence of eutrophication and hypoxic and anoxic episodes in these systems. Many urbanised estuaries are also subject to high levels of anthropogenic metal contamination. Environmental O 2 levels may influence whether sediments act as sinks or sources of metals. In this study we investigated the effect of an extended O 2 depletion event (40 days) on fluxes of trace metals (and the metalloid As) across the sediment–water interface in sediments from a highly metal contaminated estuary in S.E. Tasmania, Australia. We collected sediments from three sites that spanned a range of contamination and measured total metal concentration in the overlying water using sealed core incubations. Manganese and iron, which are known to regulate the release of other divalent cations from sub-oxic sediments, were released from sediments at all sites as hypoxia developed. In contrast, the release of arsenic, cadmium, copper and zinc was comparatively low, most likely due to inherent stability of these elements within the sediments, perhaps as a result of their refractory origin, their association with fine-grained sediments or their being bound in stable sulphide complexes. Metal release was not sustained due to the powerful effect of metal-sulphide precipitation of dissolved metals back into sediments. The limited mobilisation of sediment bound metals during hypoxia is encouraging, nevertheless the results highlight particular problems for management in areas where hypoxia might occur, such as the release of metals exacerbating already high loads or resulting in localised toxicity. - Highlights: ► Metal contaminated sediments exposed to long-term hypoxia released Mn and Fe pulses. ► As flux increased under anoxic conditions Cd, Cu and Zn fluxes occurred only during the first week of hypoxia. ► Flux of these metals from 3 sites was not related to total sediment metal

  19. Assessment of heavy metal contamination in water and sediments of Trepça and Sitnica rivers, Kosovo, using pollution indicators and multivariate cluster analysis.

    Science.gov (United States)

    Ferati, Flora; Kerolli-Mustafa, Mihone; Kraja-Ylli, Arjana

    2015-06-01

    The concentrations of As, Cd, Cr, Co, Cu, Ni, Pb, and Zn in water and sediment samples from Trepça and Sitnica rivers were determined to assess the level of contamination. Six water and sediment samples were collected during the period from April to July 2014. Most of the water samples was found within the European and Kosovo permissible limits. The highest concentration of As, Cd, Pb, and Zn originates primarily from anthropogenic sources such discharge of industrial water from mining flotation and from the mine waste eroded from the river banks. Sediment contamination assessment was carried out using the pollution indicators such as contamination factor (CF), degree of contamination (Cd), modified degree of contamination (mCd), pollution load index (PLI), and geo-accumulation index (Igeo). The CF values for the investigated metals indicated a high contaminated nature of sediments, while the Cd values indicated a very high contamination degree of sediments. The mCd values indicate a high degree of contamination of Sitnica river sediment to ultrahigh degree of contamination of Trepça river sediment. The PLI values ranged from 1.89 to 14.1 which indicate that the heavy metal concentration levels in all investigated sites exceeded the background values and sediment quality guidelines. The average values of Igeo revealed the following ranking of intensity of heavy metal contamination of the Trepça and Sitnica river sediments: Cd > As > Pb > Zn > Cu > Co > Cr > Ni. Cluster analysis suggests that As, Cd, Cr, Co, Cu, Ni, Pb, and Zn are derived from anthropogenic sources, particularly discharges from mining flotation and erosion form waste from a zinc mine plant. In order to protect the sediments from further contamination, the designing of a monitoring network and reducing the anthropogenic discharges are suggested.

  20. Selected trace-element and organic contaminants in the streambed sediments of the Potomac River Basin, August 1992

    Science.gov (United States)

    Gerhart, James M.; Blomquist, Joel D.

    1995-01-01

    This report describes the occurrence and distribution of five selected contaminants in streambed sediments at 22 stream sites in the Potomac River Basin. Lead, mercury, and total DDT (dichlorodiphenyltrichloroethane) were detected at all sites, and chlordane and total PCB's (polychlorinated biphenyls) were detected at most sites. At six sites, streambed-sediment concentrations of contaminants were detected at levels with the potential to cause frequent adverse effects on aquatic organisms that live in the sediments. Chlordane was detected at these high levels at sampling sites on the Anacostia River, the North Branch Potomac River, Bull Run, and Accotink Creek; mercury was detected at these levels at sites on the South River and the South Fork Shenandoah River; and total PCB's were detected at these levels at the site on the South Fork Shenandoah River. The highest concentrations of all five contaminants generally occurred at sampling sites downstream from areas with industrial plants, urban centers, or orchard and agricultural activity. The occurrence of these contaminants in streambed sediments of the Potomac River Basin is of concern because the contaminants (1) are environmentally persistent, (2) are available for downstream transport during high streamflow periods, and (3) have the potential to cause adverse effects on the health of aquatic organisms and humans through bioaccumulation.

  1. Ammonia gas transport and reactions in unsaturated sediments: Implications for use as an amendment to immobilize inorganic contaminants

    International Nuclear Information System (INIS)

    Zhong, L.; Szecsody, J.E.; Truex, M.J.; Williams, M.D.; Liu, Y.

    2015-01-01

    Highlights: • Ammonia transport can be predicted from gas movement and equilibrium partitioning. • Ammonia diffusion rate in unsaturated sediment is a function of water contents. • High pH induced by ammonia causes mineral dissolution and sequential precipitation. • Ammonia treatment effectively immobilized uranium from contaminated sediments. - Abstract: Use of gas-phase amendments for in situ remediation of inorganic contaminants in unsaturated sediments of the vadose zone may be advantageous, but there has been limited development and testing of gas remediation technologies. Treatment with ammonia gas has a potential for use in treating inorganic contaminants (such as uranium) because it induces a high pore-water pH, causing mineral dissolution and subsequent formation of stable precipitates that decrease the mobility of some contaminants. For field application of this treatment, further knowledge of ammonia transport in porous media and the geochemical reactions induced by ammonia treatment is needed. Laboratory studies were conducted to support calculations needed for field treatment design, to quantify advective and diffusive ammonia transport in unsaturated sediments, to evaluate inter-phase (gas/sediment/pore water) reactions, and to study reaction-induced pore-water chemistry changes as a function of ammonia delivery conditions, such as flow rate, gas concentration, and water content. Uranium-contaminated sediment was treated with ammonia gas to demonstrate U immobilization. Ammonia gas quickly partitions into sediment pore water and increases the pH up to 13.2. Injected ammonia gas advection front movement can be reasonably predicted by gas flow rate and equilibrium partitioning. The ammonia gas diffusion rate is a function of the water content in the sediment. Sodium, aluminum, and silica pore-water concentrations increase upon exposure to ammonia and then decline as aluminosilicates precipitate when the pH declines due to buffering. Up to 85% of

  2. Induction of mouthpart deformities in chironomid larvae exposed to contaminated sediments.

    NARCIS (Netherlands)

    Di Veroli, A.; Goretti, E.; León Paumen, M.; Kraak, M.H.S.; Admiraal, W.

    2012-01-01

    The aim of the present study was to improve the cause-effect relationship between toxicant exposure and chironomid mouthpart deformities, by linking induction of mouthpart deformities to contaminated field sediments, metal mixtures and a mutagenic polycyclic aromatic compound metabolite (acridone).

  3. Heavy metal contamination in stream water and sediments of gold ...

    African Journals Online (AJOL)

    This study assessed the seasonal variation in heavy metal contamination of stream water and sediments in the gold mining area of Atakunmosa West local Government, Osun State, Nigeria. Twelve villages of prominence in illegal gold mining were selected for the study covering dry and wet seasons of 2012. Stream water ...

  4. Metal release from contaminated coastal sediments under changing pH conditions: Implications for metal mobilization in acidified oceans.

    Science.gov (United States)

    Wang, Zaosheng; Wang, Yushao; Zhao, Peihong; Chen, Liuqin; Yan, Changzhou; Yan, Yijun; Chi, Qiaoqiao

    2015-12-30

    To investigate the impacts and processes of CO2-induced acidification on metal mobilization, laboratory-scale experiments were performed, simulating the scenarios where carbon dioxide was injected into sediment-seawater layers inside non-pressurized chambers. Coastal sediments were sampled from two sites with different contamination levels and subjected to pre-determined pH conditions. Sediment samples and overlying water were collected for metal analysis after 10-days. The results indicated that CO2-induced ocean acidification would provoke increased metal mobilization causing adverse side-effects on water quality. The mobility of metals from sediment to the overlying seawater was correlated with the reduction in pH. Results of sequential extractions of sediments illustrated that exchangeable metal forms were the dominant source of mobile metals. Collectively, our data revealed that high metal concentrations in overlying seawater released from contaminated sediments under acidic conditions may strengthen the existing contamination gradients in Maluan Bay and represent a potential risk to ecosystem health in coastal environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Earthworms as colonisers: Primary colonisation of contaminated land, and sediment and soil waste deposits

    NARCIS (Netherlands)

    Eijsackers, H.J.P.

    2010-01-01

    This paper reviews the role of earthworms in the early colonisation of contaminated soils as well as sediment and waste deposits, which are worm-free because of anthropogenic activities such as open-cast mining, soil sterilisation, consistent pollution or remediation of contaminated soil. Earthworms

  6. Multi-elemental contamination and historic record in sediments from the Santos-Cubatao Estuarine System, Brazil

    International Nuclear Information System (INIS)

    Luiz-Silva, Wanilson; Machado, Wilson; Matos, Rosa H.R.

    2008-01-01

    This paper records for the first time the contamination history and identifies the sources of 38 elements in sediments from the Santos-Cubatao Estuarine System (SE Brazil), at one of the most industrialized areas in Latin America. The compositions of samples from a 260 cm long sediment core collected in the Morrao River estuary were determined by ICP-MS. Enrichment factors, principal component analysis, correlation matrixes, and the characterization of geochemical signatures permitted a consistent data evaluation. Contaminant elements such as Cr, Mn, Ni, Zn, Ga, Ag, Cd, Sn, Sb, Pb, and Bi were associated with steel plant-derived Fe concentrations, while Be, Ca, Sc, Co, Cu, Sr, Y, Zr, Nb, Hf, Ta, Th, and U were associated with fertilizer industry-derived P concentrations. An overlap of sedimentary Fe distribution and local steel plant production indicated that Fe is a reliable marker of the contamination history, allowing the estimation of sedimentation rates over a period of 45 years of industrial activities. (author)

  7. Human hepatoma cells exposed to estuarine sediment contaminant extracts permitted the differentiation between cytotoxic and pro-mutagenic fractions

    International Nuclear Information System (INIS)

    Pinto, M.; Costa, P.M.; Louro, H.; Costa, M.H.; Lavinha, J.

    2014-01-01

    Complex toxicant mixtures present in estuarine sediments often render contaminant screening unfeasible and compromise determining causation. HepG2 cells were subjected to bioassays with sediment extracts obtained with a series of progressively polar solvents plus a crude extract. The sediments were collected from an impacted area of an estuary otherwise regarded as pristine, whose stressors result mostly from aquaculture effluents and hydrodynamic shifts that enhance particle deposition. Compared to a reference scenario, the most polar extracts yielded highest cytotoxicity while higher genotoxicity (including oxidative damage) was elicited by non-polar solvents. While the former caused effects similar to those expected from biocides, the latter triggered effects compatible with known pro-mutagens like PAHs, even though the overall levels of toxicants were considered of low risk. The results indicate that the approach may constitute an effective line-of-evidence to infer on the predominant set of hazardous contaminants present in complex environmental mixtures. -- Highlights: • Estuarine sediment contaminants were extracted with different organic solvents. • More polar solvents contained the most cytotoxic contaminant fraction. • Non-polar solvents extracted the main genotoxic component of the mixture. • DNA base oxidation was detected through FPG/Comet assay. • The contamination pattern could be inferred from cytoassays with HepG2 cells. -- Polar/non-polar sediment fractions elicited differential cytotoxic and genotoxic effects in human HepG2 cells

  8. Assessment of DDT, HCH and PAH contamination and associated ecotoxicological risks in surface sediments of coastal Tema Harbour (Ghana).

    Science.gov (United States)

    Botwe, Benjamin O; Kelderman, Peter; Nyarko, Elvis; Lens, Piet N L

    2017-02-15

    This study assessed DDTs, HCHs and PAHs contamination in sediments from the Tema Harbour (Ghana) and the associated ecotoxicological risks. The results showed widespread DDTs, HCHs and PAHs contamination in the harbour sediments with mean concentrations ranging from 6.0-12.8, 2.8-12.7 and 2750-5130μg·kg -1 d·w, respectively. The silt-clay and total organic carbon contents of the sediments poorly correlated with the pollutant concentrations. DDTs and HCHs contamination relate to past use of DDT and lindane, which under the anoxic harbour conditions resulted in disproportionately higher concentrations of p,p'-DDD and γ-HCH in the sediments. No conclusion could be drawn on the sources of PAHs as either petrogenic or pyrogenic. The pollutant concentrations in the harbour sediments, particularly γ-HCH, may pose high ecotoxicological risks. In comparison to a previous study, this study indicates there has been a considerable reduction in PAH contamination in the Tema Harbour since the last major oil spill in 2007. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Contribution of PAHs from coal-tar pavement sealcoat and other sources to 40 U.S. lakes

    Science.gov (United States)

    Van Metre, Peter C.; Mahler, Barbara J.

    2010-01-01

    Contamination of urban lakes and streams by polycyclic aromatic hydrocarbons (PAHs) has increased in the United States during the past 40 years. We evaluated sources of PAHs in post-1990 sediments in cores from 40 lakes in urban areas across the United States using a contaminant mass-balance receptor model and including as a potential source coal-tar-based (CT) sealcoat, a recently recognized source of urban PAH. Other PAH sources considered included several coal- and vehicle-related sources, wood combustion, and fuel-oil combustion. The four best modeling scenarios all indicate CT sealcoat is the largest PAH source when averaged across all 40 lakes, contributing about one-half of PAH in sediment, followed by vehicle-related sources and coal combustion. PAH concentrations in the lakes were highly correlated with PAH loading from CT sealcoat (Spearman's rho=0.98), and the mean proportional PAH profile for the 40 lakes was highly correlated with the PAH profile for dust from CT-sealed pavement (r=0.95). PAH concentrations and mass and fractional loading from CT sealcoat were significantly greater in the central and eastern United States than in the western United States, reflecting regional differences in use of different sealcoat product types. The model was used to calculate temporal trends in PAH source contributions during the last 40 to 100 years to eight of the 40 lakes. In seven of the lakes, CT sealcoat has been the largest source of PAHs since the 1960s, and in six of those lakes PAH trends are upward. Traffic is the largest source to the eighth lake, located in southern California where use of CT sealcoat is rare.

  10. Relating the ability of mallards to ingest high levels of sediment to potential contaminant exposure in waterfowl

    Science.gov (United States)

    Heinz, Gary H.; Beyer, W. Nelson; Hoffman, David J.; Audet, Daniel J.

    2010-01-01

    When waterfowl feed from the bottom of bodies of water, they sometimes ingest sediments along with their food, and this sediment can be a major source of contaminants. Learning how much sediment waterfowl can consume in their diet and still maintain their health would be helpful in assessing potential threats from contaminants in sediment. In a controlled laboratory study the maximum tolerated percentage of sediment in the diet of mallards (Anas platyrhynchos) was measured. When fed a well-balanced commercial avian diet, 50, 60, or 70% sediment in the diet on a dry-weight basis did not cause weight loss over a two-week period. Ducks fed this same commercial diet, but containing 80 or 90% sediment, lost 8.6 and 15.6% of their body weight, respectively, in the first week on those diets. After factoring in the ability of the mallards to sieve out some of the sediment from their diet before swallowing it, we concluded that the mallards could maintain their health even when approximately half of what they swallowed, on a dry-weight basis, was sediment.

  11. Transcriptomic analyses in a benthic fish exposed to contaminated estuarine sediments through laboratory and in situ bioassays.

    Science.gov (United States)

    Costa, Pedro M; Miguel, Célia; Caeiro, Sandra; Lobo, Jorge; Martins, Marta; Ferreira, Ana M; Caetano, Miguel; Vale, Carlos; DelValls, T A; Costa, Maria H

    2011-11-01

    The transcription of contaminant response-related genes was investigated in juvenile Senegalese soles exposed to sediments from three distinct sites (a reference plus two contaminated) of a Portuguese estuary (the Sado, W Portugal) through simultaneous 28-day laboratory and in situ bioassays. Transcription of cytochrome P450 1A (CYP1A), metallothionein 1 (MT1), glutathione peroxidase (GPx), catalase (CAT), caspase 3 (CASP3) and 90 kDa heat-shock protein alpha (HSP90AA) was surveyed in the liver by real-time PCR. CASP3 transcription analysis was complemented by surveying apoptosis through the TUNEL reaction. After 14 days of exposure, relative transcription was either reduced or decreased in fish exposed to the contaminated sediments, revealing a disturbance stress phase during which animals failed to respond to insult. After 28 days of exposure all genes' transcription responded to contamination but laboratory and in situ assays depicted distinct patterns of regulation. Although sediments revealed a combination of organic and inorganic toxicants, transcription of the CYP1A gene was consistently correlated to organic contaminants. Metallothionein regulation was found correlated to metallic and organic xenobiotic contamination in the laboratory and in situ, respectively. The transcription of oxidative stress-related genes can be a good indicator of general stress but caution is mandatory when interpreting the results since regulation may be influenced by multiple factors. As for MT1, HSP90 up-regulation has potential to be a good indicator for total contamination, as well as the CASP3 gene, even though hepatocyte apoptosis depicted values inconsistent with sediment contamination, showing that programmed cell death did not directly depend on caspase transcription alone.

  12. Evolution of radioactive dose rates in fresh sediment deposits along coastal rivers draining Fukushima contamination plume

    OpenAIRE

    Evrard, Olivier; Chartin, Caroline; Onda, Yuichi; Patin, Jeremy; Lepage, Hugo; Lef?vre, Ir?ne; Ayrault, Sophie; Ottl?, Catherine; Bont?, Philippe

    2013-01-01

    Measurement of radioactive dose rates in fine sediment that has recently deposited on channel bed-sand provides a solution to address the lack of continuous river monitoring in Fukushima Prefecture after Fukushima Dai-ichi nuclear power plant (FDNPP) accident. We show that coastal rivers of Eastern Fukushima Prefecture were rapidly supplied with sediment contaminated by radionuclides originating from inland mountain ranges, and that this contaminated material was partly exported by typhoons t...

  13. Secondary environmental impacts of remedial alternatives for sediment contaminated with hydrophobic organic contaminants.

    Science.gov (United States)

    Choi, Yongju; Thompson, Jay M; Lin, Diana; Cho, Yeo-Myoung; Ismail, Niveen S; Hsieh, Ching-Hong; Luthy, Richard G

    2016-03-05

    This study evaluates secondary environmental impacts of various remedial alternatives for sediment contaminated with hydrophobic organic contaminants using life cycle assessment (LCA). Three alternatives including two conventional methods, dredge-and-fill and capping, and an innovative sediment treatment technique, in-situ activated carbon (AC) amendment, are compared for secondary environmental impacts by a case study for a site at Hunters Point Shipyard, San Francisco, CA. The LCA results show that capping generates substantially smaller impacts than dredge-and-fill and in-situ amendment using coal-based virgin AC. The secondary impacts from in-situ AC amendment can be reduced effectively by using recycled or wood-based virgin AC as production of these materials causes much smaller impacts than coal-based virgin AC. The secondary environmental impacts are highly sensitive to the dredged amount and the distance to a disposal site for dredging, the capping thickness and the distance to the cap materials for capping, and the AC dose for in-situ AC amendment. Based on the analysis, this study identifies strategies to minimize secondary impacts caused by different remediation activities: optimize the dredged amount, the capping thickness, or the AC dose by extensive site assessments, obtain source materials from local sites, and use recycled or bio-based AC. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. In situ recovery of oil from Utah tar sand: a summary of tar sand research at the Laramie Energy Technology Center

    Energy Technology Data Exchange (ETDEWEB)

    Marchant, L.C.; Westhoff, J.D.

    1985-10-01

    This report describes work done by the United States Department of Energy's Laramie Energy Technology Center from 1971 through 1982 to develop technology for future recovery of oil from US tar sands. Work was concentrated on major US tar sand deposits that are found in Utah. Major objectives of the program were as follows: determine the feasibility of in situ recovery methods applied to tar sand deposits; and establish a system for classifying tar sand deposits relative to those characteristics that would affect the design and operation of various in situ recovery processes. Contents of this report include: (1) characterization of Utah tar sand; (2) laboratory extraction studies relative to Utah tar sand in situ methods; (3) geological site evaluation; (4) environmental assessments and water availability; (5) reverse combustion field experiment, TS-1C; (6) a reverse combustion followed by forward combustion field experiment, TS-2C; (7) tar sand permeability enhancement studies; (8) two-well steam injection experiment; (9) in situ steam-flood experiment, TS-1S; (10) design of a tar sand field experiment for air-stream co-injection, TS-4; (11) wastewater treatment and oil analyses; (12) economic evaluation of an in situ tar sand recovery process; and (13) appendix I (extraction studies involving Utah tar sands, surface methods). 70 figs., 68 tabs.

  15. Distribution of metals and extent of contamination in sediments from the south-eastern Baltic Sea (Lithuanian zone

    Directory of Open Access Journals (Sweden)

    Nijolė Remeikaitė-Nikienė

    2018-04-01

    Full Text Available Summary: The distribution of metals (Pb, Cu, Cd, Ni, Cr, Zn in surface sediments and the potential pollution sources in the south-eastern part (SE of the Baltic Sea (Lithuanian zone were investigated in relation to the environmental characteristics (amount of fine-grained particles, TOC content in sediments, origin of sedimentary organic matter, salinity, water depth in 2011–2014. The higher metal concentrations were measured in sediments of the Curonian Lagoon and in the open waters. An approach using various environmental indices (enrichment factor EF, geoaccumulation index Igeo and contamination factor CF was used to quantitatively assess a contamination degree. The principal component analysis (PCA was applied in order to further scrutinize pollution from metal sources. The values of the contamination indices showed no/very low sediment contamination with Ni and Cr, minor–moderate contamination with Cu, Zn and Pb and moderate–considerable pollution with Cd. The strong relationships among metals suggested their similar distribution pattern and a combination of natural and anthropogenic sources. The higher metal concentrations coincided with an increasing amount of fine-grained fraction and organic carbon. In the territorial waters, the distribution of elements was related to the water depth. In addition, the binding of metals with insoluble iron sulphides might explain their high concentrations at the most remote and deepest stations. Keywords: Metals, Enrichment factor, Geoaccumulation index, Contamination factor, The Baltic Sea, The Curonian Lagoon

  16. Magnetic characteristics of sediment grains concurrently contaminated with TBT and metals near a shipyard in Busan, Korea.

    Science.gov (United States)

    Choi, Jin Young; Hong, Gi Hoon; Ra, Kongtae; Kim, Kyung-Tae; Kim, Kyoungrean

    2014-08-30

    Bottom sediments near shipyards are often susceptible to receiving accidental spills of TBT and metals or their degradation products from hull scraping of antifouling system paints applied prior to 2008, when the AFS Convention 2001 was not in force. We investigated TBT and metal contamination of sediments near the shipyards of a small marina located in Busan, Korea and found that they were highly contaminated with TBT, Cu, and Zn. To better understand the environmental impacts and to make an optimal remediation plan, we characterized individual antifouling fragments in terms of metal and TBT contents, magnetic properties, and grain-size. Coarse-sized individual antifouling fragments exhibited simultaneously high levels of TBT, metals and high magnetic susceptibility, and appeared to be a major source of pollution in the sediment. Therefore, magnetic separation in combination with size-separation appears to be a cost-effective remediation method to remove the TBT and metals from contaminated shipyard sediments. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Demonstration of In Situ Treatment with Reactive Amendments for Contaminated Sediments in Active DoD Harbors

    Science.gov (United States)

    2017-06-30

    as hazardous wastes . The sediments are contaminated from the sediment bed surface to 1 foot below the sediment - water interface. The site is...enable deep water placement of the material on the sediment surface. The AquaGate, which is denser than water , sinks rapidly through the water column...zone (generally 10–20 centimeters [cm] below sediment - water interface) unless it is determined that there is little or no advective transport of

  18. Trace metals in antifouling paint particles and their heterogeneous contamination of coastal sediments

    International Nuclear Information System (INIS)

    Singh, Nimisha; Turner, Andrew

    2009-01-01

    Antifouling paint residues collected from the hard-standings of a marine leisure boat facility have been chemically characterised. Scanning electron microscopy revealed distinct layers, many containing oxidic particles of Cu and Zn. Quantitative analysis indicated concentrations of Cu and Zn averaging about 300 and 100 mg g -1 , respectively, and small proportions of these metals ( -1 , respectively. Estuarine sediment collected near a boatyard contained concentrations of Cu and Zn an order of magnitude greater than respective concentrations in 'background' sediment, and mass balance calculations suggested that the former sample was contaminated by about 1% by weight of paint particles. Clearly, antifouling residues represent a highly significant, heterogeneous source of metallic contamination in the marine environment where boating activities occur.

  19. Phytoremediation prospects of willow stands on contaminated sediment : A field trial

    NARCIS (Netherlands)

    Vervaeke, P; Luyssaert, S.; Mertens, J.; Meers, E.; Tack, F. M.G.; Lust, N

    2003-01-01

    Establishing fast growing willow stands on land disposed contaminated dredged sediment can result in the revaluation of this material and opens possibilities for phytoremediation. A field trial was designed to assess the impact of planting a willow stand (Salix viminalis L. 'Orm') on the dissipation

  20. Organic environmental poisons in Norwegian freshwater fish

    International Nuclear Information System (INIS)

    2002-01-01

    According to this article, the level of organic poisons in Norwegian freshwater fish is, on the whole, is too small to threaten human health. It has been found, however, that liver from some species such as burbot, from some lakes, should not be eaten. These lakes are found to contain higher levels of PCB (polychlorinated biphenyls) and DDT (dichlorodiphenyltrichloroethane). Previously, pregnant or breast-feeding women anywhere in Norway have been advised not to eat pike, large perch or large trout because of too much mercury. Other people should not eat these species more often than once per month. In general, the level of organic environmental poisons is higher in the southern part of the country than in the northern part. The sediments of the lakes in large parts of South Norway are contaminated with lead, mercury and cadmium as compared with the conditions before the industrial revolution. However, the level of metals in the lake sediments are relatively low, and these substances are unlikely to appear in the food chain, by and large. The anthropogenic emission of lead was insignificant before the industrial revolution. The exception of lead from German mining industry in the 1700s

  1. Rare earth elements as tracers of sediment contamination by phosphogypsum in the Santos estuary, southern Brazil

    International Nuclear Information System (INIS)

    Barros de Oliveira, Sonia Maria; Cardoso da Silva, Paulo Sergio; Paci Mazzilli, Barbara; Teixeira Favaro, Deborah Ines; Saueia, Catia Heloisa

    2007-01-01

    In the Cubatao region, southern Brazil, sediments are transported by several rivers from the Serra do Mar Ridge into the Santos estuary. Fertilizer plants have been operating along the margins of one of these rivers (Mogi River) producing a large volume of phosphogypsum, which is stockpiled in nearby areas. Surface sediments of the Mogi River were sampled upstream and downstream in relation to the point where the effluents of the phosphogypsum piles flow into the drainage system. In the vicinity of this point one sediment core was collected. Results show that REE, Ba, Zr and Th concentrations in the non-contaminated sediments are of the same order as those present in the upper continental crust. The contaminated samples present a composition affected by that of the phosphogypsum, marked by a higher concentration of these elements and a stronger degree of REE fractionation. These phosphogypsum characteristics are inherited from the Catalao igneous phosphate ore and were moderately modified by the industrial process of phosphoric acid production. The phosphogypsum signal decreases rapidly downstream, pointing to a limited area of influence of the stacks. The deepest sediments of the core are also free of contamination, representing a time interval prior to the deposition of phosphogypsum wastes on the banks of the estuary

  2. Quantification of Hydroxylated Polybrominated Diphenyl Ethers (OH-BDEs), Triclosan, and Related Compounds in Freshwater and Coastal Systems.

    Science.gov (United States)

    Kerrigan, Jill F; Engstrom, Daniel R; Yee, Donald; Sueper, Charles; Erickson, Paul R; Grandbois, Matthew; McNeill, Kristopher; Arnold, William A

    2015-01-01

    Hydroxylated polybrominated diphenyl ethers (OH-BDEs) are a new class of contaminants of emerging concern, but the relative roles of natural and anthropogenic sources remain uncertain. Polybrominated diphenyl ethers (PBDEs) are used as brominated flame retardants, and they are a potential source of OH-BDEs via oxidative transformations. OH-BDEs are also natural products in marine systems. In this study, OH-BDEs were measured in water and sediment of freshwater and coastal systems along with the anthropogenic wastewater-marker compound triclosan and its photoproduct dioxin, 2,8-dichlorodibenzo-p-dioxin. The 6-OH-BDE 47 congener and its brominated dioxin (1,3,7-tribromodibenzo-p-dioxin) photoproduct were the only OH-BDE and brominated dioxin detected in surface sediments from San Francisco Bay, the anthropogenically impacted coastal site, where levels increased along a north-south gradient. Triclosan, 6-OH-BDE 47, 6-OH-BDE 90, 6-OH-BDE 99, and (only once) 6'-OH-BDE 100 were detected in two sediment cores from San Francisco Bay. The occurrence of 6-OH-BDE 47 and 1,3,7-tribromodibenzo-p-dioxin sediments in Point Reyes National Seashore, a marine system with limited anthropogenic impact, was generally lower than in San Francisco Bay surface sediments. OH-BDEs were not detected in freshwater lakes. The spatial and temporal trends of triclosan, 2,8-dichlorodibenzo-p-dioxin, OH-BDEs, and brominated dioxins observed in this study suggest that the dominant source of OH-BDEs in these systems is likely natural production, but their occurrence may be enhanced in San Francisco Bay by anthropogenic activities.

  3. Quantification of Hydroxylated Polybrominated Diphenyl Ethers (OH-BDEs, Triclosan, and Related Compounds in Freshwater and Coastal Systems.

    Directory of Open Access Journals (Sweden)

    Jill F Kerrigan

    Full Text Available Hydroxylated polybrominated diphenyl ethers (OH-BDEs are a new class of contaminants of emerging concern, but the relative roles of natural and anthropogenic sources remain uncertain. Polybrominated diphenyl ethers (PBDEs are used as brominated flame retardants, and they are a potential source of OH-BDEs via oxidative transformations. OH-BDEs are also natural products in marine systems. In this study, OH-BDEs were measured in water and sediment of freshwater and coastal systems along with the anthropogenic wastewater-marker compound triclosan and its photoproduct dioxin, 2,8-dichlorodibenzo-p-dioxin. The 6-OH-BDE 47 congener and its brominated dioxin (1,3,7-tribromodibenzo-p-dioxin photoproduct were the only OH-BDE and brominated dioxin detected in surface sediments from San Francisco Bay, the anthropogenically impacted coastal site, where levels increased along a north-south gradient. Triclosan, 6-OH-BDE 47, 6-OH-BDE 90, 6-OH-BDE 99, and (only once 6'-OH-BDE 100 were detected in two sediment cores from San Francisco Bay. The occurrence of 6-OH-BDE 47 and 1,3,7-tribromodibenzo-p-dioxin sediments in Point Reyes National Seashore, a marine system with limited anthropogenic impact, was generally lower than in San Francisco Bay surface sediments. OH-BDEs were not detected in freshwater lakes. The spatial and temporal trends of triclosan, 2,8-dichlorodibenzo-p-dioxin, OH-BDEs, and brominated dioxins observed in this study suggest that the dominant source of OH-BDEs in these systems is likely natural production, but their occurrence may be enhanced in San Francisco Bay by anthropogenic activities.

  4. Centrifuge treatment of coal tar

    Energy Technology Data Exchange (ETDEWEB)

    L.A. Kazak; V.Z. Kaidalov; L.F. Syrova; O.S. Miroshnichenko; A.S. Minakov [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

    2009-07-15

    New technology is required for the removal of water and heavy fractions from regular coal tar. Centrifuges offer the best option. Purification of coal tar by means of centrifuges at OAO NLMK permits the production of pitch coke or electrode pitch that complies with current standards.

  5. Oil in nearshore subtidal sediments of Saudi Arabia from the Gulf War spill

    International Nuclear Information System (INIS)

    Michel, J.; Hayes, M.O.; Keenan, R.S.; Jensen, J.R.; Narumalani, S.

    1993-01-01

    Detailed sedimentological and dynamic-process studies of the shallow, subtidal habitats of Dawhats ad Dafi and al Mussallamiyah and the bays at Tanaqib on the Saudi Arabian coast were carried out one year after the Gulf War oil spill. These studies were part of Leg II of the NOAA ship Mt. Mitchell cruise. Satellite imagery and space shuttle photography were used extensively to develop detailed study plans. Work accomplished during the study included deployment of three current meters, a tide gauge, and suspended sediment traps (at seven locations). Bathymetric surveys were conducted along 14 transects, and 197 bottom observation dives were carried out. More than 170 bottom sediment samples were collected for chemical and/or textural analysis. Sediment hydrocarbon screening by HPLC fluorescence was conducted on board to verify and refine the sampling plan. The results to date show no evidence of large-scale sinking of oil as a result of the spill. Subtidal oil, as sparse tar balls, was visually observed by divers at three locations, all of which were associated with the erosion of oiled sand from outer beaches. On-board chemical results showed that subtidal sediments have been contaminated at levels ranging from 20 to 2,000 mg petroleum hydrocarbons/kg, with the highest contamination up in the sheltered, muddy basins. However, the oil initially stranded in the intertidal zone does not appear to be accumulating in the nearshore subtidal region in significant quantities one year later

  6. Preliminary Results: Release Of Metals From Acid-Mine Drainage Contaminated Streambed Sediments Under Anaerobic Conditions

    Science.gov (United States)

    Many miles of streams in the western U.S. are contaminated with acid-mine drainage (AMD) from abandoned metal mines. Treatment of these streams may include removal of the existing sediments, with subsequent burial (e.g., in a repository). Burial of previously aerobic sediments ma...

  7. Evaluation of the effects of coal fly ash amendments on the toxicity of a contaminated marine sediment

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, R.M.; Perron, M.M.; Friedman, C.L.; Suuberg, E.M.; Pennell, K.G.; Cantwell, M.G.; Pelletier, M.C.; Ho, K.T.; Serbst, J.R.; Ryba, S.A. [US EPA, Narragansett, RI (USA). Office for Research and Development

    2009-01-15

    Approaches for cleaning up contaminated sediments range from dredging to in situ treatment. In this study, we discuss the effects of amending reference and contaminated sediments with coal fly ash to reduce the bioavailability and toxicity of a field sediment contaminated with polycyclic aromatic hydrocarbons (PAHs). Six fly ashes and a coconut charcoal were evaluated in 7-d whole sediment toxicity tests with a marine amphipod (Ampelisca abdita) and mysid (Americamysis bahia). Fly ashes with high carbon content and the coconut charcoal showed proficiency at reducing toxicity. Some of the fly ashes demonstrated toxicity in the reference treatments. It is suspected that some of this toxicity is related to the presence of ammonia associated with fly ashes as a result of postoxidation treatment to reduce nitrous oxide emissions. Relatively simple methods exist to remove ammonia from fly ash before use, and fly ashes with low ammonia content are available. Fly ashes were also shown to effectively reduce overlying water concentrations of several PAHs. No evidence was seen of the release of the metals cadmium, copper, nickel, or lead from the fly ashes. A preliminary 28-d polychaete bioaccumulation study with one of the high-carbon fly ashes and a reference sediment was also performed. Although preliminary, no evidence was seen of adverse effects to worm growth or lipid content or of accumulation of PAHs or mercury from exposure to the fly ash. These data show fly ashes with high carbon content could represent viable remedial materials for reducing the bioavailability of organic contaminants in sediments.

  8. Davis Pond freshwater prediversion biomonitoring study: freshwater fisheries and eagles

    Science.gov (United States)

    Jenkins, Jill A.; Bourgeois, E. Beth; Jeske, Clint W.

    2008-01-01

    In January 2001, the construction of the Davis Pond freshwater diversion structure was completed by the U.S. Army Corps of Engineers. The diversion of freshwater from the Mississippi River is intended to mitigate saltwater intrusion from the Gulf of Mexico and to lessen the concomitant loss of wetland areas. In addition to the freshwater inflow, Barataria Bay basin would receive nutrients, increased flows of sediments, and water-borne and sediment-bound compounds. The purpose of this biomonitoring study was, therefore, to serve as a baseline for prediversion concentrations of selected contaminants in bald eagle (Haliaeetus leucocephalus) nestlings (hereafter referred to as eaglets), representative freshwater fish, and bivalves. Samples were collected from January through June 2001. Two similarly designed postdiversion studies, as described in the biological monitoring program, are planned. Active bald eagle nests targeted for sampling eaglet blood (n = 6) were generally located southwest and south of the diversion structure. The designated sites for aquatic animal sampling were at Lake Salvador, at Lake Cataouatche, at Bayou Couba, and along the Mississippi River. Aquatic animals representative of eagle prey were collected. Fish were from three different trophic levels and have varying feeding strategies and life histories. These included herbivorous striped mullet (Mugil cephalus), omnivorous blue catfish (Ictalurus furcatus), and carnivorous largemouth bass (Micropterus salmoides). Three individuals per species were collected at each of the four sampling sites. Freshwater Atlantic rangia clams (Rangia cuneata) were collected at the downstream marsh sites, and zebra mussels (Dreissena spp.) were collected on the Mississippi River. The U.S. Geological Survey (USGS) Biomonitoring of Environmental Status and Trends (BEST) protocols served as guides for fish sampling and health assessments. Fish are useful for monitoring aquatic ecosystems because they accumulate

  9. Concentrations of polycyclic aromatic hydrocarbons (PAHs) and azaarenes in runoff from coal-tar- and asphalt-sealcoated pavement

    International Nuclear Information System (INIS)

    Mahler, Barbara J.; Van Metre, Peter C.; Foreman, William T.

    2014-01-01

    Coal-tar-based sealcoat, used extensively on parking lots and driveways in North America, is a potent source of PAHs. We investigated how concentrations and assemblages of PAHs and azaarenes in runoff from pavement newly sealed with coal-tar-based (CT) or asphalt-based (AS) sealcoat changed over time. Samples of simulated runoff were collected from pavement 5 h to 111 d following application of AS or CT sealcoat. Concentrations of the sum of 16 PAHs (median concentrations of 328 and 35 μg/L for CT and AS runoff, respectively) in runoff varied relatively little, but rapid decreases in concentrations of azaarenes and low molecular weight PAHs were offset by increases in high molecular weight PAHs. The results demonstrate that runoff from CT-sealcoated pavement, in particular, continues to contain elevated concentrations of PAHs long after a 24-h curing time, with implications for the fate, transport, and ecotoxicological effects of contaminants in runoff from CT-sealcoated pavement. - Highlights: • We compare PAH and azaarene concentrations in runoff from coal-tar- and asphalt-sealed pavement. • Concentrations in coal-tar-sealcoat runoff greatly exceeded those in asphalt-sealcoat runoff. • Decreases in azaarenes and LMW PAHs were offset by increases in HMW PAHs. • PAH concentrations in coal-tar-sealcoat runoff remained high for months after application. - Concentrations of PAHs in runoff from pavement with coal-tar-based sealcoat continue to be elevated for at least 3 months following sealcoat application

  10. Measurement of oxytetracycline and emamectin benzoate in freshwater sediments downstream of land based aquaculture facilities in the Atlantic Region of Canada.

    Science.gov (United States)

    Lalonde, Benoit A; Ernst, William; Greenwood, Lyndsay

    2012-09-01

    This study investigated the occurrence of oxytetracycline (OTC) and emamectin benzoate (EB) in sediments located near the effluent outfall from four freshwater aquaculture facilities in Atlantic Canada. While two facilities had no detectable concentrations of EB or OTC, two facilities had detectable concentrations of one or both of these chemicals. Concentrations ranged from <0.05-18 mg/kg to <0.01-2.5 mg/kg for OTC and EB respectively. Although these values could not be compared with freshwater toxicant values, some of the concentrations of EB and OTC detected were higher than LC(50) values calculated for marine invertebrates. OTC concentrations measured in this study are also of a magnitude which has been known to produce resistant bacteria.

  11. Long-term environmental and health implications of morphological change and sediment transport with respect to contaminants

    Science.gov (United States)

    Sneddon, Christopher; Copplestone, David; Tyler, Andrew; Hunter, Peter; Smith, Nick

    2014-05-01

    The EPSRC-funded Adaptation and Resilience of Coastal Energy Supply (ARCoES) project encompasses four research strands, involving 14 institutions and six PhD studentships. ARCoES aims to determine the threats posed to future energy generation and the distribution network by flooding and erosion, changing patterns of coastal sedimentation, water temperature and the distribution of plants and animals in the coastal zone. Whilst this research has direct benefits for the operation of coastal power stations, ARCoES aims to have a wider stakeholder engagement through assessing how the resilience of coastal communities may be altered by five hundred years of coastal evolution. Coastal evolution will have substantial implications for the energy sector of the North West of England as former waste storage sites are eroded and remobilised within the intertidal environment. The current intertidal environmental stores of radioactivity will also experience reworking as ocean chemistry changes and saltmarsh chronologies are reworked in response to rising sea levels. There is a duel requirement to understand mass sediment movement along the North West coast of England as understanding the sediment transport dynamics is key to modelling long term coastal change and understanding how the environmental store of radioactivity will be reworked. The University of Stirling is researching the long-term environmental and health implications of remobilisation and transport of contaminated sediments around the UK coastline. Using a synergy of hyperspectral and topographic information the mobilisation of sediment bound contaminants within the coastal environment will be investigated. Potential hazards posed by contaminants are determined by a set of environmental impact test criteria which evaluate the bio-accessibility and ionising dose of contaminants. These test criteria will be used to comment on the likely environmental impact of modelled sediment transport and anticipated changes in

  12. In-Situ Survival Mechanisms of U and Tc Reducing Bacteria in Contaminated Sediments. Final Report

    International Nuclear Information System (INIS)

    Lee Krumholz Jimmy Ballard

    2005-01-01

    The proposed effort will identify genes and ultimately physiological mechanisms and pathways that are expressed under in situ conditions and are critical to functioning of aquifer dwelling anaerobic bacteria living in contaminated systems. The main objectives are: (1) Determine which Metal-reducer specific genes are important for activities in normal and contaminated subsurface sediment. To achieve these goals, we have generated a library of chromosomal mutants. These are introduced into contaminated sediments, incubated, allowed to grow, and then reisolated. A negative selection process allows us to determine which mutants have been selected against in sediments and thereby identify genes required for survival in subsurface sediments. (2) Delineate the function of these genes through GeneBank and Clusters of Orthologous Groups (COGs) comparisons and analyze other sediment microorganisms to determine if similar genes are present in these populations. After determining the sequence of the genes identified through the previous objectives, we delineate the role of those specific genes in the physiology of G20, MR-1 and perhaps other microorganisms. (3) Determine the loss in function of a select group of mutants. Cells with mutations in known genes with testable functions are assayed for the loss of that function if specific assays are available. Mutants with unknown loss of function and other mutants are run through a series of tests including motility, attachment, and rate of sulfate or iron reduction. These tests allow us to categorize mutants for subsequent more detailed study

  13. Solid-waste leach characteristics and contaminant-sediment interactions

    International Nuclear Information System (INIS)

    Serne, R.J.; LeGore, V.L.; Cantrell, K.J.; Lindenmeier, C.W.; Campbell, J.A.; Amonette, J.E.; Conca, J.L.; Wood, M.I.

    1993-10-01

    The objectives of this report and subsequent volumes include describing progress on (1) development of conceptual-release models for Hanford Site defense solid-waste forms; (2) optimization of experimental methods to quantify the release from contaminants from solid wastes and their subsequent interactions with unsaturated sediments; and (3) creation of empirical data for use as provisional source term and retardation factors that become input parameters for performance assessment analyses for future Hanford disposal units and baseline risk assessments for inactive and existing disposal units

  14. Volatilisation of aromatic hydrocarbons from soil: part II, fluxes from coal tar contaminated soils residing below the soil surface

    International Nuclear Information System (INIS)

    Lindhardt, B.; Christensen, T.H.

    1996-01-01

    The non-steady-state fluxes of aromatic hydrocarbons from coal tar contaminated soil, placed below a 5 cm deep layer of uncontaminated soil, were measured in the laboratory over a period of 53 days. The contaminated soil originated from a former gasworks site and contained concentrations of 11 selected aromatic hydrocarbons between 50 to 840 μg/cm 3 . Where the microbial activity was inhibited, the fluxes stabilized on a semi-steady-state level for the monocyclic aromatic hydrocarbons, naphthalene and 1-methylnaphthalene after a period of 10-20 days. Fluxes of acenaphthene and fluorene were only measurable in an experiment that utilized a cover soil with a low organic content. The fluxes were predicted by a numerical model assuming that the compounds acted independently of each other and that local equilibrium between the air, water, and sorbed phases existed. The model overestimated the fluxes for all the detected aromatic hydrocarbons by a factor of 1.3 to 12. When the cover soil was adapted to degrade naphthalene, the fluxes of naphthalene and 1-methylnaphthalene approached the detection limit after 5 to 8 days. Thereafter the fluxes of these two compounds were less than predicted by the model employing half-life values of 0.5 and 1 day for naphthalene and 1-methylnaphthalene respectively. 10 refs., 6 figs., 7 tabs

  15. Coal tar pitch. Interrelations between properties and utilization of coal tar pitch

    Energy Technology Data Exchange (ETDEWEB)

    Collin, G; Koehler, H [Ruetgerswerke A.G., Duisburg (Germany, F.R.)

    1977-06-01

    Coal tar pitch is won as a highly aromatic, thermoplastic residue by destillating coal tar. In this paper the structure as well as the chemical and physical data of this pitch are introduced. In addition to this the actual as well as possible applications are indicated. For example, the pitch can be used for the production of binders, e.g. for electrodes and road construction as well as in combination with plastics for the production of insulating material and corrosion protection material.

  16. Assessment of contamination and origin of metals in mining affected river sediments: A case study of the Aries catchment, Romania

    Directory of Open Access Journals (Sweden)

    Levei Erika

    2014-01-01

    Full Text Available The study presents the current status of contamination with metals (Cu, Cr, Cd, Pb, Ni, Zn, As and their anthropogenic or natural origin in the sediments of the Aries river basin, Romania, affected by mining activities. The results indicated an enrichment of metals in sediments. Different contamination levels were identified on the Aries river and its tributaries. According to sediment quality guidelines and contamination indices, sediments from the Aries river were found to be highly contaminated with Cd, Cu, As, considerably with Zn and moderately with Pb and Ni. The right-bank tributaries were found to be more contaminated than the left-bank affluents, where only a contamination with As of geogenic origin was identified. The Principal Component Analysis allowed to identify five latent factors (86 % total variability reflecting the anthropogenic and natural origins of metals. Arsenic, Cd and partially Pb were found to have a common anthropogenic origin, different from that of Cu. The statistical approach indicated also the geogenic origin of Pb due to its association with Ca, K, Na, Sr. Chromium and Ni were attributed to natural source following their association with Mn, Fe, Al and Mg, respectively.

  17. Coal tar: past, present and future

    Energy Technology Data Exchange (ETDEWEB)

    Thami, G.P.; Sarkar, R. [Government Medical College & Hospital, Chandigarh (India). Dept. of Dermatology & Venerology

    2002-03-01

    Crude coal tar has been used in the treatment of dermatoses for many decades. In the last few years its use has been limited to skin diseases such as psoriasis and chronic dermatitis. Newer topical modalities for psoriasis are being used increasingly for treatment, but have failed to replace crude coal tar as a first-line treatment of psoriasis. The authors review the pharmacology, chemistry and use of crude coal tar in order to reappraise its role as a therapeutic agent in dermatology.

  18. Sampling method, storage and pretreatment of sediment affect AVS concentrations with consequences for bioassay responses

    Energy Technology Data Exchange (ETDEWEB)

    Lange, H.J. de [Aquatic Ecology and Water Quality Management Group, Wageningen University, Wageningen University and Research Centre, P.O. Box 8080, 6700 DD, Wageningen (Netherlands); Centre for Ecosystem Studies, Alterra, Wageningen University and Research Centre, P.O. Box 47, 6700 AA, Wageningen (Netherlands)], E-mail: marieke.delange@wur.nl; Griethuysen, C. van; Koelmans, A.A. [Aquatic Ecology and Water Quality Management Group, Wageningen University, Wageningen University and Research Centre, P.O. Box 8080, 6700 DD, Wageningen (Netherlands)

    2008-01-15

    Sediment treatment and sediment storage may alter sediment toxicity, and consequently biotic response. Purpose of our study was to combine these three aspects (treatment-toxicity-biotic response) in one integrated approach. We used Acid Volatile Sulfide (AVS) concentrations as a proxy of the disturbance of the sediment. AVS and Simultaneously Extracted Metal (SEM) concentrations were compared to bioassay responses with the freshwater benthic macroinvertebrate Asellus aquaticus. Storage conditions and sediment treatment affected AVS but not SEM levels. AVS can be used as a proxy for sediment disturbance. The best way to pretreat the sediment for use in a bioassay in order to maintain initial AVS conditions was to sample the sediment with an Ekman grab, immediately store it in a jar without headspace, and freeze it as soon as possible. In a survey using seven different sediments, bioassay responses of A. aquaticus were correlated with SEM and AVS characteristics. - Change in AVS is a good proxy for sediment disturbance and combined with SEM it can be used as a suitable predictor for biotic effects of sediment contamination.

  19. Investigation of sewage contamination using steroid indexes in sediments of the Guajará Estuary (Amazon coast, Brazil

    Directory of Open Access Journals (Sweden)

    Heyde Gonçalves Gomes

    2015-12-01

    Full Text Available Abstract Amazonian aquatic systems are usually associated with pristine waters, however, irregular urban occupation of the hydrographic basins and sewerage deficiencies may lead to point and diffuse contamination. Sewage contamination in intertidal surface sediments from the Guajará Estuary, Brazilian Amazon coast, was evaluated using a set of steroids as biomarkers. Sediments collected along the urbanized margin were also analyzed for chlorophyll a, total organic carbon and grain sizes. Coprostanol, the main fecal sterol, was found at concentrations varying from 0.06 to 7.93 µg g-1 dry sediment, following the sequence Tucunduba > Ver-o-Peso > Porto da Palha > Tamandaré > Icoaraci > Miramar. Mixed sources of organic matter and coastal process probably concurred to produce weak correlations among the parameters. Plant derived sterols, including n-C30 alcohol and β-amyrinyl alkanoates, were clearly abundant, but they did not preclude the use of other steroid signals to the assessment of sewage contamination. High values of the steroid indexes involving 5α and 5β stanols and stanones highlighted sewage contamination at the sites with the lowest absolute coprostanol concentrations. The predominance of 5β stanols indicated a chronically sewage contamination of the area.

  20. Distillation of tar and tar fractions in the presence of surface-active coke

    Energy Technology Data Exchange (ETDEWEB)

    Jaeppelt, A; Klaus, J

    1943-01-01

    The tar obtained by low-temperature carbonization of Upper Silesian gas coke and fractions from this tar were distilled in the presence of different grades of coke dust with varying surface activity; the coke had been activated by steam in the course of its production by low-temperature carbonization. The surface activity of the coke dusts was measured by determining the heat of wetting with C/sub 6/H/sub 6/. Tar and coke dust, both anhydrous, were mixed in a kneading machine in such proportions that the capillaries of the dust were saturated and enough ''externally'' bound tar was present to permit briquetting. The briquets were distilled without cracking and with steam as heating medium. The yield and quality of the distillate depended on the magnitude of the internal surface of the coke dust used; a mixture of a very active coke from brown coal and tar yielded a distillate with Conradson carbon residue of 1.34 percent, asphalt content 6.1 percent and eta/sub 20/ 5.4/sup 0/ E. as compared with C residue of 10.95 percent, asphalt content 33.5 percent and eta/sub 20/ 123.6/sup 0/ E. of the distillate obtained in the absence of surface-active coke. Even higher-boiling fractions can be improved by this treatment, although it is preferable to use oils with an initial boiling point below 300/sup 0/. The ratio of oil to adsorbent is not critical, but better results were obtained with higher percentages of added coke dust. The process in its present form is not suited for the conversion of crude creosote to useful phenols.

  1. Metal contamination in benthic macroinvertebrates in a sub-basin in the southeast of Brazil

    Directory of Open Access Journals (Sweden)

    WAC Chiba

    Full Text Available Benthic macroinvertebrates have many useful properties that make possible the use of these organisms as sentinel in biomonitoring programmes in freshwater. Combined with the characteristics of the water and sediment, benthic macroinvertebrates are potential indicators of environmental quality. Thus, the spatial occurrence of potentially toxic metals (Al, Zn, Cr, Co, Cu, Fe, Mn and Ni in the water, sediment and benthic macroinvertebrates samples were investigated in a sub-basin in the southeast of Brazil in the city of São Carlos, São Paulo state, with the aim of verifying the metals and environment interaction with benthic communities regarding bioaccumulation. Hypothetically, there can be contamination by metals in the aquatic environment in the city due to lack of industrial effluent treatment. All samples were analysed by the USEPA adapted method and processed in an atomic absorption spectrophotometer. The sub-basin studied is contaminated by toxic metals in superficial water, sediment and benthic macroinvertebrates. The Bioaccumulation Factor showed a tendency for metal bioaccumulation by the benthic organisms for almost all the metal species. The results show a potential human and ecosystem health risk, contributing to metal contamination studies in aquatic environments in urban areas.

  2. Evaluation and selection of test methods for assessment of contaminated sediments in the Baltic Sea

    DEFF Research Database (Denmark)

    Lehtonen, Kari; Ahvo, Aino; Berezina, Nadya

    The purpose of the CONTEST project (2014-15) is to test, develop, evaluate and select suitable biological methods to be applied in the quantitative and qualitative assessment of toxicity of anthropogenically contaminated sediments in the Baltic Sea marine region. Here is presented results from...... showed large variability in the sensitivity of the different biotests. Most of the tests applied showed concentration-dependent effects on the test organisms. New experiments will be carried out in 2015. The CONTEST project is funded by the Nordic Council of Ministers and the Finnish Ministry...... a set of pilot experiments, which were performed by the participating laboratories. Chemical analysis of the contaminated harbour sediment chosen as the test matrix confirmed the presence of high concentrations of polycyclic aromatic hydrocarbons, organotins and trace metals, and the sediment...

  3. Heavy metal profile of water, sediment and freshwater cat fish, Chrysichthys nigrodigitatus (Siluriformes: Bagridae), of Cross River, Nigeria.

    Science.gov (United States)

    Ayotunde, Ezekiel Olatunji; Offem, Benedict Obeten; Ada, Fidelis Bekeh

    2012-09-01

    Cross River serves as a major source of drinking water, transportation, agricultural activities and fishing in Cross River State, Nigeria. Since there is no formal control of effluents discharged into the river, it is important to monitor the levels of metals contaminants in it, thus assessing its suitability for domestic and agricultural use. In order to determine this, three sampling stations designated as Ikom (Station I), Obubra Ogada (Station II) and Calabar (Station III) were randomly selected to study. For this, ten samples of the freshwater Silver Catfish (Chryshchythys nigrogitatus) (29.4-39.5cm SL, 310-510g), sediment and water were collected from each sampling Station from June 2009-June 2010. The heavy metals profiles ofZn, Cu, Fe, Co, Pb, Cd and Cr, in water, sediments and fish muscle were analyzed by atomic absorption spectrophotometry (AAS). In fish, the heavy metals concentration was found to be Cu>Fe>Zn>Cu>Pb>Cd>Co; the highest mean concentration of Copper (0.297 +/- 0.022 microg/g), Cadmium (0.011 +/- 0.007 microg/g), Iron (0.371 +/- 0.489 microg/g), Lead (0.008 +/- 0.008 microg/g), were determined for the fish. In water, the order was found to be Fe>Pb>Zn>Cu>Cr>Cd>Co; the highest mean concentration of Iron (0.009 +/- 0.00) microg/g), Copper (0.015 +/- 0.01 microg/g), Lead (0.0002 +/- 0.00 microg/g) Cadmium (0.0006 +/- 0.001 microg/g), Zinc (0.0036 +/- 0.003 microg/g), were observed in the surface water, respectively. The highest mean concentration of Copper (0.037 +/- 0.03 microg/g), Iron (0.053 +/- 0.04 microg/g), Lead (0.0002 +/- 0.00 microg/g), Cobalt (0.0002 +/- 0.00 microg/g), Cadmium (0.0006 +/- 0.001 microg/g) and Zinc (.009 +/- 0.0015 microg/g) was observed in the bottom water. In sediments, the concentration order found was Zn>Fe>Cu>Pb>Co>Cd; the highest mean concentration of 0.057 +/- 0.04 microg/g, 0.043 +/- 0.03 microg/g, 0.0006 +/- 0.00 microg/g, 0.0002 +/- 0.00 microg/g, 0.0009 +/- 0.00 microg/g, 0.099 +/- 0.00404 microg/g in Iron

  4. Environmental Risk of Metal Mining Contaminated River Bank Sediment at Redox-Transitional Zones

    Directory of Open Access Journals (Sweden)

    Sarah F. L. Lynch

    2014-01-01

    Full Text Available Diffuse metal pollution from mining impacted sediment is widely recognised as a potential source of contamination to river systems and may significantly hinder the achievement of European Union Water Framework Directive objectives. Redox-transitional zones that form along metal contaminated river banks as a result of flood and drought cycles could cause biogeochemical changes that alter the behaviour of polyvalent metals iron and manganese and anions such as sulphur. Trace metals are often partitioned with iron, manganese and sulphur minerals in mining-contaminated sediment, therefore the dissolution and precipitation of these minerals may influence the mobility of potentially toxic trace metals. Research indicates that freshly precipitated metal oxides and sulphides may be more “reactive” (more adsorbent and prone to dissolution when conditions change than older crystalline forms. Fluctuations at the oxic-anoxic interface brought about through changes in the frequency and duration of flood and drought episodes may therefore influence the reactivity of secondary minerals that form in the sediment and the flux of dissolved trace metal release. UK climate change models predict longer dry periods for some regions, interspersed with higher magnitude flood events. If we are to fully comprehend the future environmental risk these climate change events pose to mining impacted river systems it is recommended that research efforts focus on identifying the primary controls on trace metal release at the oxic-anoxic interface for flood and drought cycles of different duration and frequency. This paper critically reviews the literature regarding biogeochemical processes that occur at different temporal scales during oxic, reducing and dry periods and focuses on how iron and sulphur based minerals may alter in form and reactivity and influence the mobility of trace metal contaminants. It is clear that changes in redox potential can alter the composition

  5. Dynamics of metallic contaminants at a basin scale--Spatial and temporal reconstruction from four sediment cores (Loire fluvial system, France).

    Science.gov (United States)

    Dhivert, E; Grosbois, C; Courtin-Nomade, A; Bourrain, X; Desmet, M

    2016-01-15

    From the 19th century, the Loire basin (France) presents potentially pollutant activities such as mining and heavy industries. This paper shows spatio-temporal distribution of trace elements in sediments at a basin-scale, based on a comparison of archived temporal signals recorded in four sedimentary cores. Anthropogenic sources contributing to sediment contamination are also characterized, using geochemical signatures recorded in river bank sediments of the most industrialized tributaries. This study highlights upstream-downstream differences concerning recorded contamination phases in terms of spatial influence and temporality of archiving processes. Such differences were related to (i) various spatial influences of contamination sources and (ii) polluted sediments dispersion controlled by transport capacity of metal-carrier phases and hydrosedimentary dynamics. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Phytoremediation Of Mercury And Methylmercury Contaminated Sediments By Water Hyacinth (Eichhornia crassipes)

    Science.gov (United States)

    Phytoremediation has potential to be implemented at mercury (Hg) and methylmercury (MeHg) contaminated sites. Water hyacinths (Eichhornia crassipes) were investigated for their ability to assimilate Hg and MeHg into plant biomass, in both aquatic and sediment-associated f...

  7. Mussels and sediment as monitoring tools for contaminants: which to use when?

    Science.gov (United States)

    For decades, sediments and mussels have been used to assess the ecological and human health risks associated with concentrations of bioavailable organic and metal contaminants in a variety of coastal-wide and localized monitoring programs. Mussels (Mytilus edulis) bioaccumulate o...

  8. Stable lead isotopic characterisation of the historical record of environmental lead contamination in dated freshwater lake sediment cores from northern and central Scotland

    Energy Technology Data Exchange (ETDEWEB)

    Eades, L.J.; Farmer, J.G. [Environmental Chemistry Unit, Department of Chemistry, University of Edinburgh, West Mains Road, EH9 3JJ, Scotland Edinburgh (United Kingdom); MacKenzie, A.B. [Scottish Universities Research and Reactor Centre, East Kilbride, G75 0QF, Scotland Glasgow (United Kingdom); Kirika, A.; Bailey-Watts, A.E. [NERC Centre for Ecology and Hydrology, EH26 0QB, Scotland Penicuik (United Kingdom)

    2002-06-20

    Sediment cores from three Scottish freshwater lakes, Loch Ness in the remote north and Loch Lomond and the Lake of Menteith, much closer to the heavily populated and industrialised central belt, were analysed for 210Pb, 137Cs, Pb and stable Pb isotopic composition (206Pb/207Pb). The radionuclide data were used to establish chronologies for the Loch Ness and Loch Lomond cores, but a chronology could not be developed for the Lake of Menteith core, in which the surface sediment had been subject to intense mixing. Although Pb concentrations generally started increasing during the mid-17th Century, a small peak occurred for Loch Ness in the early 16th Century, perhaps attributable to the influence of medieval mining and smelting in mainland Europe. Temporal trends in the pattern of Pb accumulation were similar for Loch Ness and both sites in Loch Lomond, with 40-50% of the anthropogenic Pb deposited prior to the 20th Century. Fluxes of anthropogenic Pb to the lake sediments peaked during the 1950s at all locations where chronologies could be established. The 5-fold increase in anthropogenic Pb inventory for the southern basin of Loch Lomond relative to Loch Ness reflected geographical proximity to the main polluting sources. The 206Pb/207Pb data for anthropogenic Pb in the sediments from Loch Ness and Loch Lomond exhibited largely similar trends related to five different time periods. Pre-1820, the 206Pb/207Pb ratio was close to that for coal (1.181). From 1820 to 1900, a fairly constant 206Pb/207Pb ratio of 1.17 probably resulted from a combination of emissions from the smelting of indigenous Pb ore (1.170) and coal burning (1.181) in Scotland, and industrial activity to the south in England, where Australian Pb of characteristically low 206Pb/207Pb ratio (1.04) was already in use. From 1901 to 1930, the 206Pb/207Pb ratio declined by <0.01, due to the increasing influence of Australian Pb. From 1931 to 1975/1985, the 206Pb/207Pb ratio of anthropogenic Pb declined by a

  9. Stable lead isotopic characterisation of the historical record of environmental lead contamination in dated freshwater lake sediment cores from northern and central Scotland.

    Science.gov (United States)

    Eades, L J; Farmer, J G; MacKenzie, A B; Kirika, A; Bailey-Watts, A E

    2002-06-20

    Sediment cores from three Scottish freshwater lakes, Loch Ness in the remote north and Loch Lomond and the Lake of Menteith, much closer to the heavily populated and industrialised central belt were analysed for 210Pb, 137Cs, Pb and stable Pb isotopic composition (206Pb/207Pb). The radionuclide data were used to establish chronologies for the Loch Ness and Loch Lomond cores, but a chronology could not be developed for the Lake of Menteith core, in which the surface sediment had been subject to intense mixing. Although Pb concentrations generally started increasing during the mid-17th Century, a small peak occurred for Loch Ness in the early 16th Century, perhaps attributable to the influence of medieval mining and smelting in mainland Europe. Temporal trends in the pattern of Pb accumulation were similar for Loch Ness and both sites in Loch Lomond, with 40-50% of the anthropogenic Pb deposited prior to the 20th Century. Fluxes of anthropogenic Pb to the lake sediments peaked during the 1950s at all locations where chronologies could be established. The 5-fold increase in anthropogenic Pb inventory for the southern basin of Loch Lomond relative to Loch Ness reflected geographical proximity to the main polluting sources. The 206Pb/207Pb data for anthropogenic Pb in the sediments from Loch Ness and Loch Lomond exhibited largely similar trends related to five different time periods. Pre-1820, the 206Pb/207Pb ratio was close to that for coal (1.181). From 1820 to 1900, a fairly constant 206Pb/207Pb ratio of approximately 1.17 probably resulted from a combination of emissions from the smelting of indigenous Pb ore (1.170) and coal burning (1.181) in Scotland, and industrial activity to the south in England, where Australian Pb of characteristically low 206Pb/207Pb ratio (1.04) was already in use. From 1901 to 1930, the 206Pb/207Pb ratio declined by <0.01, due to the increasing influence of Australian Pb. From 1931 to 1975/1985, the 206Pb/207Pb ratio of anthropogenic Pb

  10. Remediation of organochlorine pesticides contaminated lake sediment using activated carbon and carbon nanotubes.

    Science.gov (United States)

    Hua, Shan; Gong, Ji-Lai; Zeng, Guang-Ming; Yao, Fu-Bing; Guo, Min; Ou, Xiao-Ming

    2017-06-01

    Organochlorine pesticides (OCPs) in sediment were a potential damage for humans and ecosystems. The aim of this work was to determine the effectiveness of carbon materials remedy hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethanes (DDTs) in sediment. Two different carbon materials including activated carbon (AC) and multi-walled carbon nanotubes (MWCNTs) were used in the present research. Sediment treated with 2 wt% AC and MWCNTs after 150 d contact showed 97%, and 75% reduction for HCH, and 93% and 59% decrease for DDTs in aqueous equilibrium concentration, respectively. Similarly, the reduction efficiencies of DDT and HCH uptake by semipermeable membrane devices (SPMDs) treated with AC (MWCNTs) were 97% (75%) and 92% (63%), respectively under the identical conditions. Furthermore, for 2 wt% AC (MWCNTs) system, a reduction of XAD beads uptake up to 87% (52%) and 73% (67%) was obtained in HCH and DDT flux to overlying water in quiescent system. Adding MWCNTs to contaminated sediment did not significantly decrease aqueous equilibrium concentration and DDTs and HCH availability in SPMDs compared to AC treatment. A series of results indicated that AC had significantly higher remediation efficiency towards HCH and DDTs in sediment than MWCNTs. Additionally, the removal efficiencies of two organic pollutants improved with increasing material doses and contact times. The greater effectiveness of AC was attributed to its greater specific surface area, which was favorable for binding contaminants. These results highlighted the potential for using AC as in-situ sorbent amendments for sediment remediation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Irrigation-induced contamination of water, sediment, and biota in the western United States-synthesis of data from the National Irrigation Water Quality Program

    Science.gov (United States)

    Seiler, Ralph L.; Skorupa, Joseph P.; Naftz, David L.; Nolan, B. Thomas

    2003-01-01

    In October 1985 the U.S. Department of the Interior (DOI), through the National Irrigation Water Quality Program (NIWQP), began a series of field investigations at 26 areas in the Western United States to determine whether irrigation drainage has had harmful effects on fish, wildlife, and humans or has reduced beneficial uses of water. In 1992 NIWQP initiated the Data Synthesis Project to evaluate data collected during the field investigations. Geologic, climatologic, and hydrologic data were evaluated and water, sediment, and biota from the 26 areas were analyzed to identify commonalities and dominant factors that result in irrigation-induced contamination of water and biota. Data collected for the 26 area investigations have been compiled and merged into a common data base. The structure of the data base is designed to enable assessment of relations between contaminant concentrations in water, sediment, and biota. The data base is available to the scientific community through the World Wide Web at URL http://www.usbr.gov/niwqp. Analysis of the data base for the Data Synthesis included use of summary statistics, factor analysis, and logistic regression. A Geographic Information System was used to store and analyze spatially oriented digital data such as land use, geology and evaporation rates. In the U.S. Department of the Interior (DOI) study areas, samples of water, bottom sediment, and biota were collected for trace-element and pesticide analysis. Contaminants most commonly associated with irrigation drainage were identified by comparing concentrations in water with established criteria. For surface water, the criteria used were typically chronic criteria for the protection of freshwater aquatic life. Because ground water can discharge to the surface where wildlife can be exposed to it, the criteria used for ground water were both the maximum contaminant levels (MCL's) for drinking water and the chronic criteria for the protection of freshwater aquatic life

  12. Plutonium contamination in soils and sediments at Mayak PA, Russia.

    Science.gov (United States)

    Skipperud, Lindis; Salbu, Brit; Oughton, Deborah H; Drozcho, Eugeny; Mokrov, Yuri; Strand, Per

    2005-09-01

    The Mayak Production Association (Mayak PA) was established in the late 1940's to produce plutonium for the Soviet Nuclear Weapons Programme. In total, seven reactors and two reprocessing plants have been in operation. Today, the area comprises both military and civilian reactors as well as reprocessing and metallurgical plants. Authorized and accidental releases of radioactive waste have caused severe contamination to the surrounding areas. In the present study, [alpha]-spectrometry and inductively coupled plasma-mass spectrometry (ICP-MS) have been used to determine plutonium activities and isotope ratios in soil and sediment samples collected from reservoirs of the Techa River at the Mayak area and downstream Techa River. The objective of the study was to determine the total inventory of plutonium in the reservoirs and to identify the different sources contributing to the plutonium contamination. Results based on [alpha]-spectrometry and ICP-MS measurements show the presence of different sources and confirmed recent reports of civilian reprocessing at Mayak. Determination of activity levels and isotope ratios in soil and sediment samples from the Techa River support the hypothesis that most of the plutonium, like other radionuclides in the Techa River, originated from the very early waste discharges to the Techa River between 1949 and 1951. Analysis of reservoir sediment samples suggest that about 75% of the plutonium isotopes could have been released to Reservoir 10 during the early weapons production operation of the plant, and that the majority of plutonium in Reservoir 10 originates from discharges from power production or reprocessing. Enhanced 240Pu/239Pu atom ratios in river sediment upper layers (0-2 cm) between 50 and 250 km downstream from the plant indicate a contribution from other, non-fallout sources.

  13. Influence of dams on sediment continuity: A study case of a natural metallic contamination.

    Science.gov (United States)

    Frémion, Franck; Bordas, François; Mourier, Brice; Lenain, Jean-François; Kestens, Tim; Courtin-Nomade, Alexandra

    2016-03-15

    Sediments play an important role on the quality of aquatic ecosystems, notably in the reservoir areas where they can either be a sink or a source of contaminants, depending on the management and hydrological conditions. The physicochemical properties of 25 surface sediments samples of a reservoir catchment (Vaussaire, Cantal, France) were studied. Results show a strong influence of dam presence, notably on the grain size and organic matter (OM) contents. The concentrations of trace metals and metalloids (As, Cd, Cr, Cu, Ni, Pb and Zn) were also measured and compared with worldwide reservoir concentrations and international sediment quality guideline levels in order to assess the intensity of the metallic contamination. Cr and Ni are the trace elements presenting the significantly highest values at the catchment scale. Enrichment Factors (EF), calculated using both local and national backgrounds, show that metals have mainly a natural origin, explaining especially the Cr and Ni values, linked with the composition of parental rocks. Unexpectedly, all the observed metal concentrations are lower in the reservoir than upstream and downstream, which might be related to the high fresh OM inputs in the reservoir, diluting the global metallic contamination. Multivariate statistical analyses, carried out in order to identify the relationship between the studied metals and sediment characteristics, tend to support this hypothesis, confirming the unusually low influence of such poorly-degraded OM on trace element accumulation in the reservoir. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Sediment contaminants and biological effects in southern California: Use of a multivariate statistical approach to assess biological impact

    International Nuclear Information System (INIS)

    Maxon, C.L.; Barnett, A.M.; Diener, D.R.

    1997-01-01

    This study attempts to predict biological toxicity and benthic community impact in sediments collected from two southern California sites. Contaminant concentrations and grain size were evaluated as predictors using a two-step multivariate approach. The first step used principal component analysis (PCA) to describe contamination type and magnitude present at each site. Four dominant PC vectors, explaining 88% of the total variance, each corresponded to a unique physical and/or chemical signature. The four PC vectors, in decreasing order of importance, were: (1) high molecular weight polynuclear aromatic hydrocarbons (PAH), most likely from combusted or weathered petroleum; (2) low molecular weight alkylated PAH, primarily from weathered fuel product; (3) low molecular weight nonalkylated PAH, indicating a fresh petroleum-related origin; and (4) fine-grained sediments and metals. The second step used stepwise regression analysis to predict individual biological effects (dependent) variables using the four PC vectors as independent variables. Results showed that sediment grain size alone was the best predictor of amphipod mortality. Contaminant vectors showed discrete depositional areas independent of grain size. Neither contaminant concentrations nor PCA vectors were good predictors of biological effects, most likely due to the low concentrations in sediments

  15. Contaminant levels and toxicity of sediments and water of Baltimore Harbor and Back River, Maryland

    International Nuclear Information System (INIS)

    Logan, D.T.; Jacobs, F.; Mehrotra, N.

    1995-01-01

    The Patapsco and Back River Watershed drains the Baltimore metropolitan area, Maryland's most heavily industrialized and urbanized region. Due to the intensive development and industrialization of the Baltimore metropolitan area over the past 250 years, high levels of contaminants have been discharged into Baltimore Harbor on the Patapsco River and into the Back River. Pollutants historically discharged include heavy metals, petroleum hydrocarbons, pesticides, cyanide, sewage, other organic chemicals, and nutrients. Sources have included industrial and municipal discharges, sewerage overflows, urban runoff, and leaks and spills from vessels and on-land facilities. The Maryland Department of the Environment undertook this study of ambient conditions as part of a developing strategy to assess and improve conditions in the Chesapeake Bay and its tributaries. Past studies were compiled, evaluated, and synthesized to identify the areas of degraded conditions and contaminants of possible concern. Sediment contaminant levels were assessed using historical sediment chemistry data, Effects Range Low and Median concentrations (ER-L and ER-M) as toxicological benchmarks, and a sum of toxicity units approach for multiple contaminants. Data on toxicity testing and biological monitoring was compared to sediment and water quality data. Fish tissue data were used to examine bioaccumulated chemicals. A computerized Geographical Information System (GIS) was used to manipulate and display complex geographical data. The final identification of areas and chemicals of potential concern relied on a syntheses of these results as well as information on present and past contaminant loadings

  16. Contamination and ecological risk assessment of trace elements in sediments of the rivers of Sundarban mangrove forest, Bangladesh.

    Science.gov (United States)

    Islam, M A; Al-Mamun, A; Hossain, F; Quraishi, S B; Naher, K; Khan, R; Das, S; Tamim, U; Hossain, S M; Nahid, F

    2017-11-15

    In this study, total concentrations of 16 trace elements (Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Sb, Hg, Pb, Th and U) in sediments of the rivers of the Sundarban mangrove forest, after the catastrophic oil spill accident in the Sela river of Sundarban, were determined. The overall mean concentrations of V, Cr, Fe and Cd in surface sediments of the Sundarban are remarkably higher than available literature data of those elements. Trace element contamination assessment, using different environmental contamination indices, reveals that As, Sb, Th and U are low to moderately contaminated while Cd is moderately to severely contaminated in the sediments of this area. The multivariate statistical analyses were applied to reveal the origin and behavior of the elements during their transport in the mangrove ecosystem. High Cr, Ni, Cu and As concentrations suggest the risk of potentially adverse biological effects in the ecosystem. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Electrodialytic remediation of sediments

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland

    Sediments of harbors and freshwaters are regularly dredged for various reasons: maintenance of navigational depths, recovery of recreational locations, and even environmental recovery. In the past, sediments dredged from harbors have been dumped at sea, however, environmental regulations now, in ...

  18. Problems with the dating of sediment core using excess 210Pb in a freshwater system impacted by large scale watershed changes

    International Nuclear Information System (INIS)

    Baskaran, Mark; Nix, Joe; Kuyper, Clark; Karunakara, N.

    2014-01-01

    Pb-210 dating of freshwater and coastal sediments have been extensively conducted over the past 40 years for historical pollution reconstruction studies, sediment focusing, sediment accumulation and mixing rate determination. In areas where there is large scale disturbance of sediments and the watershed, the vertical profiles of excess 210 Pb ( 210 Pb xs ) could provide erroneous or less reliable information on sediment accumulation rates. We analyzed one sediment core from Hendrix Lake in southwestern Arkansas for excess 210 Pb and 137 Cs. There is no decrease in excess 210 Pb activity with depth while the 137 Cs profile indicates sharp peak corresponding to 1963 and the 137 Cs penetration depth of 137 Cs corresponds to 1952. The historical data on the accelerated mercury mining during 1931–1944 resulted in large-scale Hg input to this watershed. Using the peak Hg activity as a time marker, the obtained sediment accumulation rates agree well with the 137 Cs-based rates. Four independent evidences (two-marker events based on 137 Cs and two marker events based on Hg mining activity) result in about the same sedimentation rates and thus, we endorse earlier suggestion that 210 Pb profile always needs to be validated with at least one another independent method. We also present a concise discussion on what important factors that can affect the vertical profiles of 210 Pb xs in relatively smaller lakes

  19. Burrowing and avoidance behaviour in marine organisms exposed to pesticide-contaminated sediment

    DEFF Research Database (Denmark)

    Møhlenberg, Flemming; Kiørboe, Thomas

    1983-01-01

    Behavioural effects of marine sediment contaminated with pesticides (6000 ppm parathion, 200 ppm methyl parathion, 200 ppm malathion) were studied in a number of marine organisms in laboratory tests and in situ. The burrowing behaviour in Macoma baltica, Cerastoderma edule, Abra alba, Nereis...

  20. Flash hydropyrolysis of bituminous coal . III. Research on flash hydropyrolysis tar

    Energy Technology Data Exchange (ETDEWEB)

    Dong, M.; Zhu, Z.; He, Y.; Ding, N.; Tang, L. [East China University of Science and Technology, Shanghai (China)

    2000-02-01

    Tar sample obtained by flash hydropyrolysis (FHP) from Dongshen coal at high pressure entrained reactor was investigated. An effect of flash hydropyrolysis temperature on the main components in tar was studied and the quality of the tar was compared with high temperature coke oven tar. The results showed that: the yields of liquid hydrocarbon in FHP tar were more than 15%, which is twofold of that in coke oven tar; the FHP tar has high oil fraction and low pitch; high phenol components and pure condensed polycyclic aromatic hydrocarbon, and low aliphatic hydrocarbon. The components of the FHP tar were simpler than that of high temperature coke oven tar. Therefore, FHP has improved the quantity and quality of tar. 11 refs., 3 figs., 5 tabs.

  1. Metal-macrofauna interactions determine microbial community structure and function in copper contaminated sediments.

    Science.gov (United States)

    Mayor, Daniel J; Gray, Nia B; Elver-Evans, Joanna; Midwood, Andrew J; Thornton, Barry

    2013-01-01

    Copper is essential for healthy cellular functioning, but this heavy metal quickly becomes toxic when supply exceeds demand. Marine sediments receive widespread and increasing levels of copper contamination from antifouling paints owing to the 2008 global ban of organotin-based products. The toxicity of copper will increase in the coming years as seawater pH decreases and temperature increases. We used a factorial mesocosm experiment to investigate how increasing sediment copper concentrations and the presence of a cosmopolitan bioturbating amphipod, Corophium volutator, affected a range of ecosystem functions in a soft sediment microbial community. The effects of copper on benthic nutrient release, bacterial biomass, microbial community structure and the isotopic composition of individual microbial membrane [phospholipid] fatty acids (PLFAs) all differed in the presence of C. volutator. Our data consistently demonstrate that copper contamination of global waterways will have pervasive effects on the metabolic functioning of benthic communities that cannot be predicted from copper concentrations alone; impacts will depend upon the resident macrofauna and their capacity for bioturbation. This finding poses a major challenge for those attempting to manage the impacts of copper contamination on ecosystem services, e.g. carbon and nutrient cycling, across different habitats. Our work also highlights the paucity of information on the processes that result in isotopic fractionation in natural marine microbial communities. We conclude that the assimilative capacity of benthic microbes will become progressively impaired as copper concentrations increase. These effects will, to an extent, be mitigated by the presence of bioturbating animals and possibly other processes that increase the influx of oxygenated seawater into the sediments. Our findings support the move towards an ecosystem approach for environmental management.

  2. Metal-macrofauna interactions determine microbial community structure and function in copper contaminated sediments.

    Directory of Open Access Journals (Sweden)

    Daniel J Mayor

    Full Text Available Copper is essential for healthy cellular functioning, but this heavy metal quickly becomes toxic when supply exceeds demand. Marine sediments receive widespread and increasing levels of copper contamination from antifouling paints owing to the 2008 global ban of organotin-based products. The toxicity of copper will increase in the coming years as seawater pH decreases and temperature increases. We used a factorial mesocosm experiment to investigate how increasing sediment copper concentrations and the presence of a cosmopolitan bioturbating amphipod, Corophium volutator, affected a range of ecosystem functions in a soft sediment microbial community. The effects of copper on benthic nutrient release, bacterial biomass, microbial community structure and the isotopic composition of individual microbial membrane [phospholipid] fatty acids (PLFAs all differed in the presence of C. volutator. Our data consistently demonstrate that copper contamination of global waterways will have pervasive effects on the metabolic functioning of benthic communities that cannot be predicted from copper concentrations alone; impacts will depend upon the resident macrofauna and their capacity for bioturbation. This finding poses a major challenge for those attempting to manage the impacts of copper contamination on ecosystem services, e.g. carbon and nutrient cycling, across different habitats. Our work also highlights the paucity of information on the processes that result in isotopic fractionation in natural marine microbial communities. We conclude that the assimilative capacity of benthic microbes will become progressively impaired as copper concentrations increase. These effects will, to an extent, be mitigated by the presence of bioturbating animals and possibly other processes that increase the influx of oxygenated seawater into the sediments. Our findings support the move towards an ecosystem approach for environmental management.

  3. Physical and performance properties of coal tar urethanes - pipe

    International Nuclear Information System (INIS)

    Hickney, J.; Hendry, M.

    1984-01-01

    The purpose of this paper is to review certain physical properties of coal tar extended urethane coatings designed specifically for use in the pipe coatings market. The blend of coal tar and urethane resins provides a novel finished product with properties cumulatively inherent in its constituents. Typically, coal tar and coal tar pitch offer exceptional water resistance and cathodic alkali resistance when blended with other resins. An example is the standard coal tar epoxies used for many years in the marine markets for shipbottoms

  4. Evaluation and assessment of baseline metal contamination in surface sediments from the Bernam River, Malaysia.

    Science.gov (United States)

    Kadhum, Safaa A; Ishak, Mohd Yusoff; Zulkifli, Syaizwan Zahmir

    2016-04-01

    The Bernam River is one of the most important rivers in Malaysia in that it provides water for industries and agriculture located along its banks. The present study was conducted to assess the level of contamination of heavy metals (Cd, Ni, Cr, Sn, and Fe) in surface sediments in the Bernam River. Nine surface sediment samples were collected from the lower, middle, and upper courses of the river. The results indicated that the concentrations of the metals decreased in the order of Sn > Cr > Ni > Fe > Cd (56.35, 14.90, 5.3, 4.6, and 0.62 μg/g(1) dry weight). Bernam River sediments have moderate to severe enrichment for Sn, moderate for Cd, and no enrichment for Cr, Ni, and Fe. The contamination factor (CF) results demonstrated that Cd and Sn are responsible for the high contamination. The pollution load index (PLI), for all the sampling sites, suggests that the sampling stations were generally unpolluted with the exception of the Bagan Tepi Sungai, Sabak Bernam, and Tanjom Malim stations. Multivariate techniques including Pearson's correlation and hierarchical cluster analysis were used to apportion the various sources of the metals. The results suggested that the sediment samples collected from the upper course of the river had lower metal concentrations, while sediments in the middle and lower courses of the river had higher metal concentrations. Therefore, our results can be useful as a baseline data for government bodies to adopt corrective measure on the issues related to heavy metal pollution in the Bernam River in the future.

  5. Assessment of sediment contamination at Great Lakes Areas of Concern: the ARCS Program Toxicity-Chemistry Work Group strategy

    Science.gov (United States)

    Ross, P.E.; Burton, G.A.; Crecelius, E.A.; Filkins, J. C.; Giesy, J.P.; Ingersoll, C.G.; Landrum, P.F.; Mac, M.J.; Murphy, T.J.; Rathbun, J. E.; Smith, V. E.; Tatem, H. E.; Taylor, R.W.

    1992-01-01

    In response to a mandate in Section 118(c)(3) of the Water Quality Act of 1987, a program called Assessment and Remediation of Contaminated Sediments (ARCS) was established. Four technical work groups were formed. This paper details the research strategy of the Toxicity-Chemistry Work Group.The Work Group's general objectives are to develop survey methods and to map the degree of contamination and toxicity in bottom sediments at three study areas, which will serve as guidance for future surveys at other locations. A related objective is to use the data base that will be generated to calculate sediment quality concentrations by several methods. The information needed to achieve these goals will be collected in a series of field surveys at three areas: Saginaw Bay (MI), Grand Calumet River (IN), and Buffalo River (NY). Assessments of the extent of contamination and potential adverse effects of contaminants in sediment at each of these locations will be conducted by collecting samples for physical characterization, toxicity testing, mutagenicity testing, chemical analyses, and fish bioaccumulation assays. Fish populations will be assessed for tumors and external abnormalities, and benthic community structure will be analyzed. A mapping approach will use low-cost indicator parameters at a large number of stations, and will extrapolate by correlation from traditional chemical and biological studies at a smaller number of locations. Sediment toxicity testing includes elutriate, pore water and whole sediment bioassays in a three-tiered framework. In addition to the regular series of toxicity tests at primary mater stations, some stations are selected for a more extensive suite of tests.

  6. Characterization of acid tar waste from benzol purification | Danha ...

    African Journals Online (AJOL)

    The use of concentrated sulphuric acid to purify benzene, toluene and xylene produces acidic waste known as acid tar. The characterization of the acid tar to determine the composition and physical properties to device a way to use the waste was done. There were three acid tars two from benzene (B acid tar), toluene and ...

  7. The Lagoon of Ravenna (Italy). Characterisation of mercury-contaminated sediments

    Energy Technology Data Exchange (ETDEWEB)

    Fabbri, D.; Lombardo, M.; Trombini, C.; Vassura, I. [Laboratorio di Chimica Ambientale, Universita di Bologna, Ravenna (Italy); Felisatti, O. [Ambiente SpA, Ravenna (Italy)

    1998-05-06

    Between 1958 and 1973, the wetland called Pialassa Baiona near Ravenna (Italy) had been heavily polluted by industrial effluents, among which mercury represented the most hazardous contaminant. Three sediment cores representative of a channel and a pond in the southern area, close to the discharge point, were analysed. Up to 244 {mu}g/g (dry weight) of mercury were observed in the top 0-20 cm layer. Among various parameters under study, good correlation was found between mercury and redox properties of the sediment, sulphur and organic matter. Styrene/butadiene based polymers, produced by the same industrial area since 1958, were found to be an important component of organic matter. Despite the analogy with the Minamata case, mercury appears to be efficiently trapped by the sediment, probably in the form of sulphide and/or bound to the organic matter and so far it has not represented a hazard for public health as confirmed by the lack of epidemiological effects in Ravenna area due to exposure to mercury

  8. A preliminary study on the phytoremediation of antibiotic contaminated sediment.

    Science.gov (United States)

    Hoang, Thuy Thi Thanh; Tu, Loan Thi Cam; Le Nga, Phi; Dao, Quoc Phu

    2013-01-01

    In Vietnam's coastal wetlands, fluoroquinolones, a widely used class of antibiotics in shrimp farming, are frequently detected in sediments of former shrimp farms. This phenomenon could lead to negative impacts on the aquatic ecosystem, since the antibiotic residues could induce changes in the microorganism communities of the water body. The potential of native wetland plants (Acrostichum aureum L. and Rhizophora apiculata Blume Fl. Javae) for phytoremediation of fluoroquinolones (ciprofloxacin and norfloxacin) was investigated. The half-life for each antibiotic was estimated at approximately 10 days in the planted sediment. With respect to the accumulation of ciprofloxacin and norfloxacin in plants, these antibiotics were found mainly in roots. Antibiotic translocation from root to stem and leaves occurred at a low rate. The results showed that A. aureum and R. apiculata can be valuable for the phytoremediation of antibiotic-contaminated sediments. Additionally, the initialfindings of the presence of resistant bacteria indicated that bacteria could play a role in facilitating the phytodegradation.

  9. Preliminary Results: Release Of Metals From Acid-Mine Drainage Contaminated Streambed Sediments Under Anaerobic Conditions (Presentation)

    Science.gov (United States)

    Many miles of streams in the western U.S. are contaminated with acid-mine drainage (AMD) from abandoned metal mines. Treatment of these streams may include removal of the existing sediments, with subsequent burial (e.g., in a repository). Burial of previously aerobic sediments ma...

  10. Response of core microbial consortia to hydrocarbon contaminations in coastal sediment habitats

    Directory of Open Access Journals (Sweden)

    Mathilde Jeanbille

    2016-10-01

    Full Text Available Traditionally, microbial surveys investigating the effect of chronic anthropogenic pressure such as polyaromatic hydrocarbons (PAHs contaminations consider just the alpha and beta diversity and ignore the interactions among the different taxa forming the microbial community. Here, we investigated the ecological relationships between the three domains of life (i.e. Bacteria, Archaea and Eukarya using 454 pyrosequencing data of the 16S rRNA and 18S rRNA genes from chronically impacted and pristine sediments, along the coasts of the Mediterranean Sea (Gulf of Lion, Vermillion coast, Corsica, Bizerte lagoon and Lebanon and the French Atlantic Ocean (Bay of Biscay and English Channel. Our approach provided a robust ecological framework for the partition of the taxa abundance distribution into 859 core OTUs and 6629 satellite OTUs. OTUs forming the core microbial community showed the highest sensitivity to changes in environmental and contaminant variations, with salinity, latitude, temperature, particle size distribution, total organic carbon (TOC and PAH concentrations as main drivers of community assembly. The core communities were dominated by Gammaproteobacteria and Deltaproteobacteria for Bacteria, by Thaumarchaeota, Bathyarchaeota and Thermoplasmata for Archaea and Metazoa and Dinoflagellata for Eukarya. In order to find associations among microorganisms, we generated a co-occurrence network in which PAHs were found to impact significantly the potential predator – prey relationship in one microbial consortium composed of ciliates and Actinobacteria. Comparison of network topological properties between contaminated and non-contaminated samples showed substantial differences in the structure of the network and indicated a higher vulnerability to environmental perturbations in the contaminated sediments.

  11. Ammonia-oxidizing Bacteria and Archaea in the Rhizosphere of Freshwater Macrophytes

    DEFF Research Database (Denmark)

    Herrmann, Martina; Schramm, Andreas

    2007-01-01

    AMMONIA-OXIDIZING ARCHAEA AND BACTERIA IN THE RHIZOSPHERE OF FRESHWATER MACROPHYTES Martina Herrmann and Andreas Schramm Department of Biological Sciences, Microbiology, University of Aarhus, Denmark Aquatic macrophytes such as Littorella uniflora and Lobelia dortmanna release oxygen from...... their roots and thereby stimulate nitrification and coupled nitrification-denitrification in their rhizosphere. However, oxygen release and inorganic nitrogen concentrations differ markedly between macrophyte species. We therefore propose (i) that the rhizosphere of freshwater macrophytes harbours a species......-specific microbial community distinct from that of unvegetated sediment and (ii) that aquatic macrophytes have an impact on abundance and activity of nitrifying and denitrifying bacteria in freshwater sediment. The goal of this study was to test these hypotheses for the key functional group for coupled nitrification...

  12. Accumulation patterns of lipophilic organic contaminants in surface sediments and in economic important mussel and fish species from Jakarta Bay, Indonesia

    International Nuclear Information System (INIS)

    Dwiyitno; Dsikowitzky, Larissa; Nordhaus, Inga; Andarwulan, Nuri; Irianto, Hari Eko; Lioe, Hanifah Nuryani; Ariyani, Farida; Kleinertz, Sonja

    2016-01-01

    Non-target screening analyses were conducted in order to identify a wide range of organic contaminants in sediment and animal tissue samples from Jakarta Bay. High concentrations of di-iso-propylnaphthalenes (DIPNs), linear alkylbenzenes (LABs) and polycyclic aromatic hydrocarbons (PAHs) were detected in all samples, whereas phenylmethoxynaphthalene (PMN), DDT and DDT metabolites (DDX) were detected at lower concentrations. In order to evaluate the uptake and accumulation by economic important mussel (Perna viridis) and fish species, contaminant patterns of DIPNs, LABs and PAHs in different compartments were compared. Different patterns of these contaminant groups were found in sediment and animal tissue samples, suggesting compound-specific accumulation and metabolism processes. Significantly higher concentrations of these three contaminant groups in mussel tissue as compared to fish tissue from Jakarta Bay were found. Because P. viridis is an important aquaculture species in Asia, this result is relevant for food safety. - Highlights: • Analyses of surface sediment and animal tissue samples from a tropical coastal system • Non-target screening enabled identification of a wide range of organic contaminants. • Comparison of contaminant patterns in surface sediments and animal tissue samples • Results illustrate compound-specific accumulation and metabolism processes. • Higher concentrations of all contaminants in mussel tissue as compared to fish tissue

  13. Polycyclic aromatic hydrocarbon (PAH) contamination of surface sediments and oysters from the inter-tidal areas of Dar es Salaam, Tanzania

    International Nuclear Information System (INIS)

    Gaspare, Lydia; Machiwa, John F.; Mdachi, S.J.M.; Streck, Georg; Brack, Werner

    2009-01-01

    Surface sediment and oyster samples from the inter-tidal areas of Dar es Salaam were analyzed for 23 polycyclic aromatic hydrocarbons (PAHs) including the 16 compounds prioritized by US-EPA using GC/MS. The total concentration of PAHs in the sediment ranged from 78 to 25,000 ng/g dry weight, while oyster concentrations ranged from 170 to 650 ng/g dry weight. Hazards due to sediment contamination were assessed using Equilibrium Partitioning Sediment Benchmarks and Threshold Effect Levels. Diagnostic indices and principle component analysis were used to identify possible sources. Interestingly, no correlation between sediment and oyster concentrations at the same sites was found. This is supported by completely different contamination patterns, suggesting different sources for both matrices. Hazard assessment revealed possible effects at six out of eight sites on the benthic communities and oyster populations. The contribution of PAH intake via oyster consumption to carcinogenic risks in humans seems to be low. - PAH contamination may pose hazards to benthos but limited risks to humans

  14. Polycyclic aromatic hydrocarbon (PAH) contamination of surface sediments and oysters from the inter-tidal areas of Dar es Salaam, Tanzania

    Energy Technology Data Exchange (ETDEWEB)

    Gaspare, Lydia; Machiwa, John F. [Department of Aquatic Environment and Conservation, University of Dar es Salaam, P.O. Box 60091, Dar es Salaam (Tanzania, United Republic of); Mdachi, S.J.M. [Department of Chemistry, University of Dar es Salaam, P.O. Box 35062, Dar es Salaam (Tanzania, United Republic of); Streck, Georg [UFZ Helmholtz Centre for Environmental Research Leipzig-Halle, Department of Effect-Directed Analysis, Permoserstrasse 15, 04318 Leipzig (Germany); Brack, Werner [UFZ Helmholtz Centre for Environmental Research Leipzig-Halle, Department of Effect-Directed Analysis, Permoserstrasse 15, 04318 Leipzig (Germany)], E-mail: werner.brack@ufz.de

    2009-01-15

    Surface sediment and oyster samples from the inter-tidal areas of Dar es Salaam were analyzed for 23 polycyclic aromatic hydrocarbons (PAHs) including the 16 compounds prioritized by US-EPA using GC/MS. The total concentration of PAHs in the sediment ranged from 78 to 25,000 ng/g dry weight, while oyster concentrations ranged from 170 to 650 ng/g dry weight. Hazards due to sediment contamination were assessed using Equilibrium Partitioning Sediment Benchmarks and Threshold Effect Levels. Diagnostic indices and principle component analysis were used to identify possible sources. Interestingly, no correlation between sediment and oyster concentrations at the same sites was found. This is supported by completely different contamination patterns, suggesting different sources for both matrices. Hazard assessment revealed possible effects at six out of eight sites on the benthic communities and oyster populations. The contribution of PAH intake via oyster consumption to carcinogenic risks in humans seems to be low. - PAH contamination may pose hazards to benthos but limited risks to humans.

  15. Reduction of metal exposure of Daubenton's bats (Myotis daubentonii) following remediation of pond sediment as evidenced by metal concentrations in hair.

    Science.gov (United States)

    Flache, Lucie; Ekschmitt, Klemens; Kierdorf, Uwe; Czarnecki, Sezin; Düring, Rolf-Alexander; Encarnação, Jorge A

    2016-03-15

    Transfer of contaminants from freshwater sediments via aquatic insects to terrestrial predators is well documented in spiders and birds. Here, we analyzed the metal exposure of Myotis daubentonii using an urban pond as their preferred foraging area before and after a remediation measure (sediment dredging) at this pond. Six metal elements (Zn, Cu, Cr, Cd, Pb and Ni) were measured in the sediment of the pond, in EDTA extracts of the sediment and in hair samples of M. daubentonii foraging at the pond. Samples were taken before remediation in 2011 and after remediation in 2013. Metal concentrations were quantified by ICP-OES after miniaturized microwave assisted extraction. In 2011, the pond sediment exhibited a high contamination with nickel, a moderate contamination with copper and chromium and low contents of zinc, cadmium and lead. While sediment metal contents declined only weakly after remediation, a much more pronounced reduction in the concentrations of zinc, copper, chromium and lead concentrations was observed in bat hair. Our results suggest a marked decline in metal exposure of the bats foraging at the pond as a consequence of the remediation measure. It is concluded that Daubenton's bats are suitable bioindicators of metal contamination in aquatic environments, integrating metal exposure via prey insects over their entire foraging area. We further suggest that bat hair is a useful monitoring unit, allowing a non-destructive and non-invasive assessment of metal exposure in bats. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Elevated in-home sediment contaminant concentrations - the consequence of a particle settling-winnowing process from Hurricane Katrina floodwaters.

    Science.gov (United States)

    Ashley, Nicholas A; Valsaraj, Kalliat T; Thibodeaux, Louis J

    2008-01-01

    Sediment samples were collected from two homes which were flooded in the wake of Hurricane Katrina in August 2005. The samples were analyzed for trace metals and semi-volatile organic compounds using techniques based on established EPA methods. The data showed higher concentrations of some metals and semi-volatile organic pollutants than reported in previous outdoor sampling events of soils and sediments. The Lake Pontchartrain sediments became resuspended during the hurricane, and this material subsequently was found in the residential areas of New Orleans following levee breaches. The clay and silt particles appear to be selectively deposited inside homes, and sediment contaminant concentrations are usually greatest within this fraction. Re-entry advisories based on outdoor sample concentration results may have under-predicted the exposure levels to homeowners and first responders. All contaminants found in the sediment sampled in this study have their origin in the sediments of Lake Pontchartrain and other localized sources.

  17. Possible developments for ex situ phytoremediation of contaminated sediments, in tropical and subtropical regions - Review.

    Science.gov (United States)

    Pittarello, Marco; Busato, Jader Galba; Carletti, Paolo; Dobbss, Leonardo Barros

    2017-09-01

    The growing problem of remediation of contaminated sediments dredged from harbor channels needs to be resolved by a cost effective and sustainable technology. Phytoremediation, by ex situ remediation plants, seems to have the potential to replace traditional methods in case of moderately contaminated sediments. On the other side, the need to mix sediments with soil and/or sand to allow an easier establishment of most employed species causes an increase of the volume of the processed substrate up to 30%. Moreover the majority of phytoremediating species are natives of temperate climate belt. Mangroves, with a special focus on the genus Avicennia - a salt secreting species - should represent an effective alternative in terms of adaptation to salty, anoxic sediments and an opportunity to develop ex situ phytoremediation plants in tropical and subtropical regions. The use of humic acid to increase root development, cell antioxidant activity and the potential attenuation of the "heavy metals exclusion strategy" to increase phytoextraction potentials of mangroves will be reviewed. Copyright © 2017. Published by Elsevier Ltd.

  18. An approach for assessing potential sediment-bound contaminant threats near the intake of a drinking water treatment plant.

    Science.gov (United States)

    Chen, Fei; Anderson, William B; Huck, Peter M

    2013-01-01

    To assist in assessing a potential contaminated sediment threat near a drinking water intake in a large lake, a technique known as the fingerprint analysis of leachate contaminants (FALCON), was investigated and enhanced to help draw more statistically significant definitive conclusions. This represents the first application of this approach, originally developed by the USEPA to characterize and track leachate penetration in groundwater and contaminant migration from waste and landfill sites, in a large lake from the point-of-view of source water protection. FALCON provided valuable information regarding contaminated sediment characterization, source attribution, and transport within a surface water context without the need for knowledge of local hydrodynamic conditions, potentially reducing reliance on complicated hydrodynamic analysis. A t-test to evaluate the significance of correlations was shown to further enhance the FALCON procedure. In this study, the sensitivity of FALCON was found to be improved by using concentration data from both conserved organics and heavy metals in combination. Furthermore, data analysis indicated that it may be possible to indirectly assess the success of remediation efforts (and the corresponding need to plan for a treatment upgrade in the event of escalating contaminant concentrations) by examining the temporal change in correlation between the source and intake sediment fingerprints over time. This method has potential for widespread application in situations where conserved contaminants such as heavy metals and higher molecular weight polycyclic aromatic hydrocarbons (PAHs), are being or have previously been deposited in sediment somewhere in, or within range of, an intake protection zone. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. The temporal relationship between advertising and sales of low-tar cigarettes.

    Science.gov (United States)

    Reed, Mark B; Anderson, Christy M; Burns, David M

    2006-12-01

    To determine whether a temporal relationship exists between the advertising and sales of low-tar cigarettes. It was hypothesised that increases in the advertising of low-tar cigarettes would precede increases in sales for these cigarettes. The themes of cigarette advertisements were reviewed and coded for 20 low-tar cigarette brands advertised in 13 widely read magazines in the US between 1960 and 1996. These 20 brands represented most of the low-tar cigarette advertisements and cigarette sales from 1967 to 1996. Cigarette sales data were obtained from the 1994 Maxwell report that summarises all cigarette sales from 1925 to 1990. If the advertisement referred to the low-tar attributes of the cigarette advertised, the advertisement was coded as having a low-tar theme and was included in the analysis. Five different graphical presentations of the relationship between the advertising and sales of the 20 low-tar cigarette brands showed a temporal relationship between low-tar advertising and sales for these brands. This relationship was observed for brands that introduced a low-tar alternative into an existing brand family (eg, Marlboro Light) and for new exclusively low-tar brands (eg, Carlton). Despite large increases in the advertising for the exclusively low-tar brands, sales of these brands remained low relative to sales of the low-tar alternative brands. Increases in print advertising of 20 of the most popular low-tar cigarette brands were followed by increases in sales for these cigarettes. Despite increases in the advertising of exclusively low-tar brands in the mid-1970s and early 1980s, the sales of these brands never matched the sales of the low-tar alternative brands. This suggests that it may have been easier to get smokers to switch to low-tar brands within a brand family compared with entirely new low-tar brands. Over the past 30 years, the marketing of low-tar cigarettes as a healthier alternative to higher-tar cigarettes has resulted in these brands

  20. Sediment quality criteria: A review with recommendations for developing criteria for the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Driver, C.J.

    1994-05-01

    Criteria for determining the quality of liver sediment are necessary to ensure that concentrations of contaminants in aquatic systems are within acceptable limits for the protection of aquatic and human life. Such criteria should facilitate decision-making about remediation, handling, and disposal of contaminants. Several approaches to the development of sediment quality criteria (SQC) have been described and include both descriptive and numerical methods. However, no single method measures all impacts at all times to all organisms (U.S. EPA 1992b). The U.S. EPA`s interest is primarily in establishing chemically based, numerical SQC that are applicable nation-wide (Shea 1988). Of the approaches proposed for SQC development, only three are being considered for numerical SQC on a national level. These approaches include an Equilibrium Partitioning Approach, a site-specific method using bioassays (the Apparent Effects Threshold Approach), and an approach similar to EPA`s water quality criteria (Pavlou and Weston 1984). Although national (or even regional) criteria address a number of political, litigative, and engineering needs, some researchers feel that protection of benthic communities require site-specific, biologically based criteria (Baudo et al. 1990). This is particularly true for areas where complex mixtures of contaminants are present in sediments. Other scientifically valid and accepted procedures for freshwater SQC include a background concentration approach, methods using field or spiked bioassays, a screening level concentration approach, the Apparent Effects Threshold Approach, the Sediment Quality Triad, the International Joint Commission Sediment Assessment Strategy, and the National Status and Trends Program Approach. The various sediment assessment approaches are evaluated for application to the Hanford Reach and recommendations for Hanford Site sediment quality criteria are discussed.