Bioconcentration of TNT and RDX in coastal marine biota.

Science.gov (United States)

Ballentine, Mark; Tobias, Craig; Vlahos, Penny; Smith, Richard; Cooper, Christopher

2015-05-01

The bioconcentration factor (BCF) was measured for 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in seven different marine species of varying trophic levels. Time series and concentration gradient treatments were used for water column and tissue concentrations of TNT, RDX, and their environmentally important derivatives 2-amino-4,6-dintrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT). BCF values ranged from 0.0031 to 484.5 mL g(-1) for TNT and 0.023 to 54.83 mL g(-1) for RDX. The use of log K ow value as an indicator was evaluated by adding marine data from this study to previously published data. For the munitions in this study, log K ow value was a good indicator in the marine environment. The initial uptake and elimination rates of TNT and RDX for Fucus vesiculosus were 1.79 and 0.24 h(-1) for TNT and 0.50 and 0.0035 h(-1) for RDX respectively. Biotransformation was observed in all biota for both TNT and RDX. Biotransformation of TNT favored 4-ADNT over 2-ADNT at ratios of 2:1 for F. vesiculosus and 3:1 for Mytilus edulis. Although RDX derivatives were measureable, the ratios of RDX derivatives were variable with no detectable trend. Previous approaches for measuring BCF in freshwater systems compare favorably with these experiments with marine biota, yet significant gaps on the ultimate fate of munitions within the biota exist that may be overcome with the use stable isotope-labeled munitions substrates.

Comparison of cadmium and chromium bioconcentration factors between scaled and scale less fish species: common carp and sutchi (striped catfish

Directory of Open Access Journals (Sweden)

Sideh Zainab Abedi

2014-10-01

Full Text Available Background: Water-borne, indissoluble heavy metals are bioaccumulated in fish (human food source. In this research, chromium (Cr and cadmium (Cd bioconcentration factors (BCFs in the skin, gills, scales, livers and muscles of two widely-consumed fish species, scaled common carp Cyprinus carpio and scaleless catfish Pangasius hypophthalmus were compared. Material and Methods: Lethal concentrations of Cd and Cr (64.89 & 7.46, and 84.8 & 17.05 mg/L for the catfish and carp, respectively were determined during 96 hrs (96 h LC50, and the fishes were exposed for 15 days. Then the tissue samples were chemically digested and the contents of Cd and Cr were determined using atomic absorption. Results: Total contents of Cr and Cd in the catfish's tissues were 2286.11 & 360.73, and those of Cr & Cd in carp were 734.71 & 725.67 μg/g.dw (excluding the scales, respectively. Metal concentrations in the water residues (day 15 revealed lower Cr and Cd (0.059 & 0.0036 mg/L in the catfish than those in the carp media (0.1 & 0.0412 mg/L, respectively. In common carp, BCF of Cd was as liver > skin > gills > muscle > scales, and those in the catfish marked as liver>muscle >gills >skin. The BCF of Cr in common carp ranked as gills>liver>skin>scales>muscle, and the catfish showing a BCF pattern of Cr as liver> muscle>skin>gills. Conclusion: This study signifies that small amounts of cadmium and chromium with high BCFs especially in the muscles of scale less fish (catfish threat consumers’ health.

Bioconcentration of atrazine and chlorophenols into roots and shoots of rice seedlings

International Nuclear Information System (INIS)

Su Yuhong; Zhu Yongguan

2006-01-01

Accumulation of o-chlorophenol (CP), 2,4-dichlorophenol (DCP), and atrazine (ATR), as single and mixed contaminants, from hydroponic solutions into roots and shoots of rice seedlings was studied following 48-h exposure of the plant roots. As single contaminants at low levels, the observed bioconcentration factors (BCFs) of CP and DCP with roots approximated the equilibrium values according to the partition-limited model. The BCF of atrazine with roots was about half the partition limit for unknown reasons. The BCFs of CP and ATR with shoots also approximated the partition limits, while the BCF for more lipophilic DCP with shoots was about half the estimated limit, due to insufficient water transport into plants for DCP. As mixed contaminants at low levels, the BCFs with both roots and shoots were comparable with those for the single contaminants; at high levels, the BCFs generally decreased because of the enhanced mixed-contaminant phytotoxicity, as manifested by the greatly reduced plant transpiration rate. - Uptakes of o-chlorophenol, 2,4-dichlorophenol, and atrazine at various levels from nutrient solution by roots and shoots of rice seedlings were investigated using a partition-limited model

Radiological bioconcentration factors for aquatic, terrestrial, and wetland ecosystems at the Savannah River Site

International Nuclear Information System (INIS)

Cummins, C.L.

1994-09-01

As a result of operations at the Savannah River Site (SRS), over 50 radionuclides have been released to the atmosphere and to onsite streams and seepage basins. Now, many of these radionuclides are available to aquatic and/or terrestrial organisms for uptake and cycling through the food chain. Knowledge about the uptake and cycling of these radionuclides is now crucial in evaluating waste management and clean-up alternatives for the site. Numerous studies have been conducted at the SRS over the past forty years to study the uptake and distribution of radionuclides in the Savannah River Site environment. In many instances, bioconcentration factors have been calculated to quantify the uptake of a radionuclide by an organism from the surrounding medium (i.e., soil or water). In the past, it has been common practice to use bioconcentration factors from the literature because site-specific data were not readily available. However, because of the variability of bioconcentration factors due to experimental or environmental conditions, site-specific data should be used when available. This report compiles and summarizes site-specific bioconcentration factors for selected radionuclides released at the Savannah River Site (SRS). An extensive literature search yielded site-specific bioconcentration factors for cesium, strontium, cobalt, plutonium, americium, curium, and tritium. These eight radionuclides have been the primary radionuclides studied at SRS because of their long half lives or because they are major contributors to radiological dose from exposure. For most radionuclides, it was determined that the site-specific bioconcentration factors were higher than those reported in literature. This report also summarizes some conditions that affect radionuclide bioavailability to and bioconcentration by aquatic and terrestrial organisms

On the variability of plant bio-concentration factors (BCF) of environmental radionuclides. A case study on the effects of surface film and free space on the interpretation of 99mTcO4- sorption in duckweed

International Nuclear Information System (INIS)

Wolterbeek, H.T.; Van der Meer, A.J.G.M.; Dielemans, U.

2000-01-01

The present paper addresses plant bioaccumulation factor (BCF) variability, and specifically focuses attention upon the handling of duckweed (Lemna gibba) material, sampled from experimental media, especially considering accumulation/kinetic studies with 99mTcO 4 - . In these short-term studies, relatively small BCF-values may be encountered, with related interferences in its assessment due to the presence of 99mTcO 4 - in the surface film medium (SF) and in the cellular water free spaces (FS). The sample handling methods used to remove the SF+FS component of the accumulated 99mTcO 4 - consisted of blotting, centrifugation and rinsing. The three methods were investigated using d-[1- 14 C]mannitol, 42K + , 82Br - and 99mTcO 4 - radioisotopes, which were measured by - and γ-spectrometry, in both solution and solid samples. Centrifugation seems the most promising method to remove SF+FS 99mTcO 4 - . Results based on both mass analysis and radioactivity determinations in centrifugated fluids are independent of applied concentrations (10 -11 to 10 -3 mol m -3 99mTcO 4 - ), and are invariably compatible with the conceptual idea of the FS as a free-entrance phase for solutes. Blotting results in an overestimation of BCF values (up to factor 3 for the 99mTcO 4 - experiments performed), probably due to the incomplete removal of the SF+FS, and is suggested to yield irregular results, leading to high variances in BCF values obtained. The application of an efflux/rinsing period is indicated to result in an underestimation of BCF values (up to factor 10 for the 99mTcO 4 - experiments performed), probably due to excess removal of (non-SF+FS) components of accumulated solutes. Here we advocate centrifugation as a routine sample handling method to avoid SF+FS interferences in short-term (kinetic) 99mTcO 4 - uptake studies in duckweed. Moreover, the results suggest a more general applicability of centrifugation as a sample handling method to avoid SF+FS interferences in short

In-situ partitioning and bioconcentration of polycyclic aromatic hydrocarbons among water, suspended particulate matter, and fish in the Dongjiang and Pearl Rivers and the Pearl River Estuary, China

International Nuclear Information System (INIS)

Li, Haiyan; Lu, Lei; Huang, Wen; Yang, Juan; Ran, Yong

2014-01-01

Highlights: • PAHs are relatively higher in marine fish than in freshwater fish. • PAHs respectively show significant correlations with DOC, POC, and Chl a. • The log K oc for PAHs is one order magnitude higher than the predicted. • The log BCF values in fish and their tissues are nonlinear in respect to log K ow . • Lipid is related to PAHs in freshwater fish, but not in marine fishes. - Abstract: The partitioning and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matter (SPM), and fish samples from the Dongjiang River (DR), Pearl River (PR), and the Pearl River Estuary (PRE) were examined. Although PAHs are much lower in PRE than in DR or PR, PAHs in some fish species are significantly higher in PRE than in DR or PR. Aqueous or particulate PAHs respectively show significant correlations with dissolved organic carbon, particulate organic matter, and chlorophyll a, suggesting that biological pumping effect regulates their distribution. The in situ partitioning coefficients (log K oc ) for PAHs are one order magnitude higher than the empirical log K oc –log K ow correlation. The bioconcentration factor (BCF) is slightly higher for the marine fish than for the freshwater fish. The above phenomena indicate that BCF may vary due to the diversity of fish species, feeding habits, and metabolism of PAHs in fish

Factors affecting heavy metal uptake in plant selection for phytoremediation

Energy Technology Data Exchange (ETDEWEB)

Anton, A.; Mathe-Gaspar, G. [Research Inst. for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences, Budapest (Hungary)

2005-04-01

The heavy metal uptake of ten plant species was studied under different soil and climatic conditions. Effects of soil pH, temperature, plant species and phenophase on the heavy metal content of stems and leaves were determined in pot experiments. Plants and soil samples were collected from a lead/zinc mine ore (Gyoengyoesoroszi, Hungary) and characterised by high contents of Pb, Zn, As, Cd, Cu. The possibility of an adapted phytoremediation technology was indicated by different bioconcentration factors (BCF). The BCF depended markedly (10- to 100-fold) on plant species and environmental conditions. Based on our results a ''season-adapted'' phytoextraction technology with different plant species (utilising their different temperature requirements and/or harvest time) is suggested. (orig.)

Ramie (Boehmeria nivea)'s uranium bioconcentration and tolerance attributes.

Science.gov (United States)

Wang, Wei-Hong; Luo, Xue-Gang; Liu, Lai; Zhang, Yan; Zhao, Hao-Zhou

2018-04-01

The authors sampled and analyzed 15 species of dominant wild plants in Huanan uranium tailings pond in China, whose tailings' uranium contents were 3.21-120.52 μg/g. Among the 15 species of wild plants, ramie (Boehmeria nivea) had the strongest uranium bioconcentration and transfer capacities. In order to study the uranium bioconcentration and tolerance attributes of ramie in detail, and provide a reference for the screening remediation plants to phytoremedy on a large scale in uranium tailings pond, a ramie cultivar Xiangzhu No. 7 pot experiment was carried out. We found that both wild ramie and Xiangzhu No. 7 could bioconcentrate uranium, but there were two differences. One was wild ramie's shoots bioconcentrated uranium up to 20 μg/g (which can be regarded as the critical content value of the shoot of uranium hyperaccumulator) even the soil uranium content was as low as 5.874 μg/g while Xiangzhu No. 7's shoots could reach 20 μg/g only when the uranium treatment concentrations were 275 μg/g or more; the other was that all the transfer factors of 3 wild samples were >1, and the transfer factors of 27 out of 28 pot experiment samples were uranium hyperaccumulator. Xiangzhu No. 7 satisfied the needs of uranium hyperaccumulator on accumulation capability, tolerance capability, bioconcentration factor, but not transfer capability, so Xiangzhu No. 7 was not a uranium hyperaccumulator. We analyzed the possible reasons why there were differences in the uranium bioconcentration and transfer attributes between wild ramie and Xiangzhu No. 7., and proposed the direction for further research. In our opinion, both the plants which bioconcentrate contaminants in the shoots and roots can act as phytoextractors. Although Xiangzhu No. 7's biomass and accumulation of uranium were concentrated on the roots, the roots were small in volume and easy to harvest. And Xiangzhu No. 7's cultivating skills and protection measures had been developed very well. Xiangzhu No. 7's

Mercury in Orange Birch Bolete Leccinum versipelle and soil substratum: bioconcentration by mushroom and probable dietary intake by consumers.

Science.gov (United States)

Krasińska, Grażyna; Falandysz, Jerzy

2016-01-01

The aim of this study was to examine the contamination, accumulation, and distribution of mercury in fruiting bodies by Leccinum versipelle fungus collected from distant sites across Poland. Mercury was determined using validated method by cold-vapor atomic absorption spectroscopy after direct sample matrix combustion. A large set of data gained using 371 fruiting bodies and 204 soil samples revealed the susceptibility of L. versipelle to Hg contamination and permitted the estimation of probable intake of Hg contaminant by consumers foraging for this species. The range of median values of Hg determined in caps of L. versipelle was from 0.20 to 2.0 mg kg(-1) dry biomass, and the median for 19 localities was 0.65 mg kg(-1) dry biomass. The values of the Hg bioconcentration factor (BCF) determined for L. versipelle correlated negatively with Hg contents. Mercury in topsoil beneath L. versipelle ranged from 0.019 to 0.041 mg kg(-1) dry matter for less-contaminated locations (BCF of 17 to 65 for caps) and from 0.076 to 0.39 mg kg(-1) dry matter for more contaminated locations (BCF of 1.9 to 22). Fruiting bodies of L. versipelle collected in some regions of Poland if consumed in amount of 300 g in one meal in a week could provide Hg doses above the provisionally tolerable weekly intake (PTWI) value of 0.004 mg Hg kg(-1) body mass, while regular consumptions for most of the locations were below the limit even with more frequent consumption. Also summarized are available data on Hg for three species of fungi of genus Leccinum foraged in Europe.

Using BCF as a mediator for task management in building design

DEFF Research Database (Denmark)

Treldal, Niels; Parsianfar, Hussain; Karlshøj, Jan

2016-01-01

buildingSMART has adopted the BIM Collaboration Format (BCF) to improve interoperability in the field of process information exchange. The original scope of BCF was linked to a need to communicate BIM-related tasks, but a further expansion of the BCF format should be considered to add additional ...

Acute toxicity and bioconcentration of 14C-fenvalerate in tilapianilotica, the Bioavilability and biological activity of its residues in rats

International Nuclear Information System (INIS)

Aly, M.A.S.

2003-01-01

Fresh water fish tilapia treated with 300 MU/L of 1 4C-fenvalerate died at 24 h post treatment with (Ld50, 12 h). however, when sand sediments were pure in the glass aquaria (250 g/L), 50% of fish survived with (Lc50 extended to 72-96 h) a bioconcentration factor (BCF) of 800 for fenvalerate was observed at 24 h in tilapia. Maximum accumulation of 1 4C-fenvalerate in fish was at 24 h (15.6 Mg/g) and 50% eliminated in 96 h. At the end of depuration period of 8 days 36% of radioactivity (3.0 Mg/g) could be recovered in fish (40% in head, the rest in different parts of body). In believability study, when rats were fed on dried fish the majority of radioactivity was eliminated at 48 h (19.0% in urine and 68.6% in faeces) with majority of radioactivity eliminated as fenvalerate equivalent in 5 days

A Bayesian approach to assessing the uncertainty in estimating bioconcentration factors in earthworms--the example of quinoxyfen.

Science.gov (United States)

Fragoulis, George; Merli, Annalisa; Reeves, Graham; Meregalli, Giovanna; Stenberg, Kristofer; Tanaka, Taku; Capri, Ettore

2011-06-01

Quinoxyfen is a fungicide of the phenoxyquinoline class used to control powdery mildew, Uncinula necator (Schw.) Burr. Owing to its high persistence and strong sorption in soil, it could represent a risk for soil organisms if they are exposed at ecologically relevant concentrations. The objective of this paper is to predict the bioconcentration factors (BCFs) of quinoxyfen in earthworms, selected as a representative soil organism, and to assess the uncertainty in the estimation of this parameter. Three fields in each of four vineyards in southern and northern Italy were sampled over two successive years. The measured BCFs varied over time, possibly owing to seasonal changes and the consequent changes in behaviour and ecology of earthworms. Quinoxyfen did not accumulate in soil, as the mean soil concentrations at the end of the 2 year monitoring period ranged from 9.16 to 16.0 µg kg⁻¹ dw for the Verona province and from 23.9 to 37.5 µg kg⁻¹ dw for the Taranto province, with up to eight applications per season. To assess the uncertainty of the BCF in earthworms, a probabilistic approach was used, firstly by building with weighted bootstrapping techniques a generic probabilistic density function (PDF) accounting for variability and incompleteness of knowledge. The generic PDF was then used to derive prior distribution functions, which, by application of Bayes' theorem, were updated with the new measurements and a posterior distribution was finally created. The study is a good example of probabilistic risk assessment. The means of mean and SD posterior estimates of log BCFworm (2.06, 0.91) are the 'best estimate values'. Further risk assessment of quinoxyfen and other phenoxyquinoline fungicides and realistic representative scenarios for modelling exercises required for future authorization and post-authorization requirements can now use this value as input. Copyright © 2011 Society of Chemical Industry.

Toxic effects, bioconcentration and depuration of verapamil in the early life stages of common carp (Cyprinus carpio L.)

Energy Technology Data Exchange (ETDEWEB)

Steinbach, Christoph, E-mail: steinbach@frov.jcu.cz [Research Institute of Fish Culture and Hydrobiology, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, CZ-38925 Vodnany (Czech Republic); Fedorova, Ganna [Research Institute of Fish Culture and Hydrobiology, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, CZ-38925 Vodnany (Czech Republic); Prokes, Miroslav [Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, v.v.i., Kvetna 8, 603 65 Brno (Czech Republic); Grabicova, Katerina; Machova, Jana; Grabic, Roman; Valentova, Olga; Kroupova, Hana Kocour [Research Institute of Fish Culture and Hydrobiology, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, CZ-38925 Vodnany (Czech Republic)

2013-09-01

Verapamil is a pharmaceutical that belongs to a group of calcium channel blockers and is mainly used as a treatment of angina pectoris and arterial hypertension. Verapamil has been detected in aquatic environments in concentrations ranging from ng L{sup −1} to μg L{sup −1}. In the present study, a series of acute toxicity tests of verapamil on various developmental stages of common carp (Cyprinus carpio) were conducted. As a result, 96hLC{sub 50} values of verapamil were estimated at 16.4 ± 9.2, 7.3 ± 1.5 and 4.8 ± 0.2 mg L{sup −1} for embryos (E5–E9) and common carp larvae L2 and L5, respectively. Lethal concentrations of verapamil decreased with an increase in the age of the fish. Acute exposure to verapamil significantly reduced the heart rate in the embryos and larvae. In an embryo-larval toxicity test (sub-chronic exposure), the bioconcentration, depuration, and toxic effects of verapamil were assessed in common carp. The fish were exposed to verapamil in a concentration of 0.463 (environmentally relevant), 4.63, 46.3 and 463 μg L{sup −1}. Verapamil had no effect on the accumulated mortality, hatching, condition factor, growth or ontogeny of the fish in any of the tested concentrations. In carp exposed to 463 and 46.3 μg L{sup −1} of verapamil, significantly higher occurrences of malformations and edemas were observed compared to the control. The bioconcentration factor of verapamil in whole fish homogenates ranged between 6.6 and 16.6 and was therefore below the critical value for hazard substances (BCF > 500). The half-life and the 95% depuration time for the tested compound were estimated to be 10.2 ± 1.6 days and 44.2 ± 8.6 days, respectively. No effects of verapamil on the studied endpoints were observed at environmentally relevant concentrations. - Highlights: • Study of the acute and sub-chronic toxicity of verapamil on early-life stages of common carp. • Acute exposure to verapamil reduced the heart rate in early-life stages of

Toxic effects, bioconcentration and depuration of verapamil in the early life stages of common carp (Cyprinus carpio L.)

International Nuclear Information System (INIS)

Steinbach, Christoph; Fedorova, Ganna; Prokes, Miroslav; Grabicova, Katerina; Machova, Jana; Grabic, Roman; Valentova, Olga; Kroupova, Hana Kocour

2013-01-01

Verapamil is a pharmaceutical that belongs to a group of calcium channel blockers and is mainly used as a treatment of angina pectoris and arterial hypertension. Verapamil has been detected in aquatic environments in concentrations ranging from ng L −1 to μg L −1 . In the present study, a series of acute toxicity tests of verapamil on various developmental stages of common carp (Cyprinus carpio) were conducted. As a result, 96hLC 50 values of verapamil were estimated at 16.4 ± 9.2, 7.3 ± 1.5 and 4.8 ± 0.2 mg L −1 for embryos (E5–E9) and common carp larvae L2 and L5, respectively. Lethal concentrations of verapamil decreased with an increase in the age of the fish. Acute exposure to verapamil significantly reduced the heart rate in the embryos and larvae. In an embryo-larval toxicity test (sub-chronic exposure), the bioconcentration, depuration, and toxic effects of verapamil were assessed in common carp. The fish were exposed to verapamil in a concentration of 0.463 (environmentally relevant), 4.63, 46.3 and 463 μg L −1 . Verapamil had no effect on the accumulated mortality, hatching, condition factor, growth or ontogeny of the fish in any of the tested concentrations. In carp exposed to 463 and 46.3 μg L −1 of verapamil, significantly higher occurrences of malformations and edemas were observed compared to the control. The bioconcentration factor of verapamil in whole fish homogenates ranged between 6.6 and 16.6 and was therefore below the critical value for hazard substances (BCF > 500). The half-life and the 95% depuration time for the tested compound were estimated to be 10.2 ± 1.6 days and 44.2 ± 8.6 days, respectively. No effects of verapamil on the studied endpoints were observed at environmentally relevant concentrations. - Highlights: • Study of the acute and sub-chronic toxicity of verapamil on early-life stages of common carp. • Acute exposure to verapamil reduced the heart rate in early-life stages of common carp. • The

Uptake of polychlorinated biphenyls and organochlorine pesticides from soil and air into radishes (Raphanus sativus)

DEFF Research Database (Denmark)

Mikes, Ondrej; Cupr, P.; Trapp, Stefan

2009-01-01

Uptake of organochlorine pesticides and polychlorinated biphenyls from soil and air into radishes was measured at a heavily contaminated field site. The highest contaminant concentrations were found for DDT and its metabolites, and for beta-hexachlorocyclohexane. Bioconcentration factor (BCF, def...

Bioconcentration of haloxyfop-methyl in bluegill (Lepomis macrochirus Rafinesque)

International Nuclear Information System (INIS)

Murphy, P.G.; Lutenske, N.E.

1990-01-01

Bluegill (Lepomis macrochirus Rafinesque) were exposed to a 14 C haloxyfop-methyl [methyl 2-(4-((3-chloro-5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoate] concentration averaging 0.29 μg/L under flow-through conditions for 28 days. At the end of 28 days, the fish were transferred to clean water for a 4-day flow-through clearance period. Bluegill were found to rapidly absorb the ester from water which was then biotransformed at an extremely fast rate within the fish, such that essentially no haloxyfop-methyl was detected in the fish. The estimated bioconcentration factor for haloxyfop-methyl in whole fish was 14 C residue within whole fish was haloxyfop acid [2-(4-((3-chloro-5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoic acid] which accounted for an average of about 60% of the total radioactivity. The high rate of biotransformation of the parent compound within the fish demonstrates the importance of basing the bioconcentration factor upon the actual concentration of parent material within the organism rather than the total radioactive residue levels for bioconcentration studies with radiolabeled compounds

Quantitative structure-activity relationships for the toxicity and bioconcentration factor of nitrobenzene derivatives towards the guppy (Poecilia reticulata)

NARCIS (Netherlands)

Deneer, J.W.; Sinnige, T.L.; Seinen, W.; Hermens, J.L.M.

The acute toxicity and bioconcentration factor of a series of nitrobenzene derivatives was determined for the guppy. Toxicity is found to be determined by both hydrophobicity (expressed by the octanol/water partition coefficient) and rate of reduction of the nitro group (expressed by either

Role of pH for the bioconcentration of ionizable organic compounds

DEFF Research Database (Denmark)

Trapp, Stefan; Franco, Antonio

-values determined at different pH. As second tool, a dynamic cell model based on the Fick-Nernst-Planck equation was tested. For the BCF fish of monovalent acids and bases, the BCF regressions and the cell model performed similar. For the BCF of water plants and plant roots, the regression failed to predict the BCF...

Piperonyl butoxide enhances the bioconcentration and photoinduced toxicity of fluoranthene and benzo[a]pyrene to larvae of the grass shrimp (Palaemonetes pugio).

Science.gov (United States)

Weinstein, John E; Garner, Thomas R

2008-04-08

Piperonyl butoxide (PBO) is a commonly used synergist in many pyrethroid formulations due to its ability to interfere with cytochrome P450 (CYP) monooxygenases. Because PBO can co-occur in the estuarine environment with polycyclic aromatic hydrocarbons (PAHs), a class of compounds metabolized by CYP isozymes, the overall objective of this study was to investigate the influence of PBO on the bioconcentration and photoinduced toxicity of two common PAH contaminants, fluoranthene (FLU) and benzo[a]pyrene (BaP), on the larvae of the grass shrimp (Palaemonetes pugio). PBO alone was not particularly toxic to grass shrimp larvae. In dark exposures and under simulated sunlight (UV-A=211.0+/-7.0 microW/cm(2), UV-B=9.8+/-2.4microW/cm(2)), 96-h LC(50) values were similar (814.4 and 888.6 microg/L, respectively), suggesting that PBO toxicity is not enhanced in the presence of sunlight. The presence of sublethal concentrations of PBO in single PAH toxicity tests increased the bioconcentration of the two tested PAHs, and these increases were greatest at the lowest tested PAH concentrations. Mean bioconcentration factors (BCF) at the three lowest FLU and BaP treatments increased 14.3- and 7.1-fold, respectively, in the low PBO (127 microg/L) exposure compared to that of the no PBO exposure. Under simulated sunlight, PBO exposure also increased the photoinduced toxicity of the two tested PAHs, and this increase occurred in a PBO concentration-dependent fashion. For FLU, 96-h LC(50) values decreased from 2.35 microg/L in the absence of PBO to 0.76 microg/L in the high PBO (256 microg/L) exposure. For BaP, 96-h LC(50) values similarly decreased from 1.02 microg/L in the absence of PBO to 0.30microg/L in the high PBO exposure. The presence of PBO also influenced the PAH tissue residue-response relationship, but in different ways for FLU and BaP. For FLU, slopes of the tissue residue-response relationship decreased in the presence of PBO, and for BaP, there was a trend towards

Radiological bioconcentration factors for aquatic, terrestrial, and wetland ecosystems at the Savannah River site

International Nuclear Information System (INIS)

Friday, G.P.; Cummins, C.L.; Schwartzman, A.L.

1996-01-01

Since the early 1950s, the Savannah River Site (SRS) released over 50 radionuclides into the environment while producing nuclear defense materials. These releases directly exposed aquatic and terrestrial biota to ionizing radiation from surface water, soil, and sediment, and also indirectly by the ingestion of items in the food chain. As part of new missions to develop waste management strategies and identify cost-effective environmental restoration options, knowledge concerning the uptake and distribution of these radionuclides is essential. This report compiles and summarizes site-specific bioconcentration factors for selected radionuclides released at SRS

Radiological bioconcentration factors for aquatic, terrestrial, and wetland ecosystems at the Savannah River site

Energy Technology Data Exchange (ETDEWEB)

Friday, G.P.; Cummins, C.L.; Schwartzman, A.L.

1996-12-31

Since the early 1950s, the Savannah River Site (SRS) released over 50 radionuclides into the environment while producing nuclear defense materials. These releases directly exposed aquatic and terrestrial biota to ionizing radiation from surface water, soil, and sediment, and also indirectly by the ingestion of items in the food chain. As part of new missions to develop waste management strategies and identify cost-effective environmental restoration options, knowledge concerning the uptake and distribution of these radionuclides is essential. This report compiles and summarizes site-specific bioconcentration factors for selected radionuclides released at SRS.

Uptake of Cadmium by Lemna minor, a (hyper?- accumulator plant involved in phytoremediation applications

Directory of Open Access Journals (Sweden)

Bianconi D.

2013-04-01

Full Text Available Metal pollution in waters and soils is a major environmental and human health problem. Cadmium (Cd2+ is a heavy metal displaying toxic effects in plants. In this work we studied the potentiality of Lemna minor, a monocotyledonous aquatic macrophyte, to phytoremediate cadmium-polluted waters. The plants were exposed to different cadmium concentrations 0, 13, 22 and 46μM CdSO4 for a period of 24, 48 and 72 hours. Relative growth rates (RGR, bioconcentration factor (BCF, tolerance index (Ti, cadmium uptake in whole plant and maximum efficiency of PSII (Fv/Fm were measured under controlled climate conditions. RGR, Ti and Fv/Fm declined with increasing exposure time and cadmium concentrations, while the BCF and cadmium uptake showed an opposite behavior. Data analysis of RGR, BCF, Tiand FV/FM indicates that L. minor maintains a good capacity of growth, metal bioconcentration, tolerance and efficiency of PSII up to 48h in plants exposed to 13 and 22μM CdSO4. Our results exhibited that L. minor is a good cadmium accumulator and is able to remediate Cd-polluted waters, especially at low Cd concentrations.

Uptake, accumulation and some biochemical responses in ...

African Journals Online (AJOL)

Under the conditions of these increasing zinc concentrations, the highest zinc accumulation was obtained in the roots of the plants treated with 10 mM applications. The zinc concentration in the vegetative parts, was highest in the root and was lowest in the cotyledons. The highest bioconcentration factor (BCF) value was ...

A comparative study on capability of different tree species in accumulating heavy metals from soil and ambient air.

Science.gov (United States)

Alahabadi, Ahmad; Ehrampoush, Mohammad Hassan; Miri, Mohammad; Ebrahimi Aval, Hamideh; Yousefzadeh, Samira; Ghaffari, Hamid Reza; Ahmadi, Ehsan; Talebi, Parvaneh; Abaszadeh Fathabadi, Zeynab; Babai, Fatemeh; Nikoonahad, Ali; Sharafi, Kiomars; Hosseini-Bandegharaei, Ahmad

2017-04-01

Heavy metals (HMs) in the urban environment can be bio-accumulated by plant tissues. The aim of this study was to compare fourteen different tree species in terms of their capability to accumulate four airborne and soilborne HMs including; zinc (Zn), copper (Cu), lead (Pb), and cadmium (Cd). Samplings were performed during spring, summer, and fall seasons. To compare bioaccumulation ability, bio-concentration factor (BCF), comprehensive bio-concentration index (CBCI), and metal accumulation index (MAI) were applied. Species with the highest accumulation for single metal which shown using BCF did not have the highest CBCI and MAI. Based on CBCI and MAI, Pinus eldarica (7.74), Wistaria sinensis (8.82), Morus alba (8.7), and Nigral morus (27.15) had the highest bioaccumulation capacity of HMs, respectively. Therefore, these species can be used for phytoextraction of HMs pollution and green and buffer zone in the urban. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influences of binding to dissolved organic matter on hydrophobic organic compounds in a multi-contaminant system: Coefficients, mechanisms and ecological risks

International Nuclear Information System (INIS)

Li, Yi-Long; He, Wei; Liu, Wen-Xiu; Kong, Xiang-Zhen; Yang, Bin; Yang, Chen; Xu, Fu-Liu

2015-01-01

The complexation flocculation (CF) method was successfully employed to identify binding coefficients (K_d_o_c) of specific organic contaminants to dissolved organic matter (DOM, often indicated by dissolved organic carbon, DOC) in a multi-contaminant hydrophobic organic contaminant (HOC) system. K_d_o_c values were obtained for most of the evaluated 33 HOCs, indicating the feasibility and applicability of the CF method in a multi-contaminant system. Significant positive correlations were observed between binding coefficients and octanol–water partition coefficients (K_o_w) for organic halogen compounds, such as polybrominated diphenyl ethers (PBDEs) (R"2 = 0.95, p < 0.05) and organic chlorine pesticides (OCPs) (methoxychlor excluded, R"2 = 0.82, p < 0.05). The positive correlations identified between the lgK_d_o_c and lgBCF (bioconcentration factor) for PBDEs and OCPs, as well as the negative correlation observed for polycyclic aromatic hydrocarbons (PAHs), indicated that different binding or partition mechanisms between PAHs and organic halogen compounds exist. These differences further result in discriminative competition partitions of HOCs between DOM and organisms. Assuming that only freely dissolved HOCs are bioconcentrative, the results of DOM-influenced bioconcentration factor (BCF_D_O_M) and DOM-influenced lowest observed effect level (LOEL_D_O_M) indicate that the ecological risk of HOCs is decreased by DOM. - Highlights: • Complexing-flocculation is viable in measuring K_d_o_c in a multi-polluted system. • The binding mechanisms between PAHs and organic halogens were different. • DOM should be considered when assessing ecological risk of HOCs in natural ecosystem. - Assuming only freely dissolved HOCs are effective, bioconcentration factors and ecological risks of HOCs are decreased by dissolved organic matter via binding.

Selection of bioaccumulation criteria for environmental emergency (E2) planning

International Nuclear Information System (INIS)

Ketcheson, K.; Hradecky, K.; Gagne, M.; St-Amant-Verret, M.

2006-01-01

Environment Canada's Environmental Emergency regulations require the evaluation of a substance by a Risk Evaluation Framework (REF). Bioaccumulation criteria are used within the environmental hazard ratings section of the REF to determine the risk of a substance to organisms and are obtained from 3 types of measurements depending on data reliability: (1) bioaccumulation factors (BAF); (2) bioconcentration factors (BCF); and (3) an octanol-water partition coefficient (log K ow ). This paper presented details of a study of international and regional bioaccumulation criteria conducted to aid in determining appropriate criteria for E2 regulations and plans, with specific reference to substances toxic to aquatic organisms. An E2 plan is required if a substance has a bioconcentration factor of more than 500 in conjunction with aquatic toxicity. Bioaccumulation criteria from several sources for 745 substances were obtained to aid in choosing the most important parameters. Various international and regional criteria were examined and corresponding sources were summarized, and different source criteria was compared with empirical chemical data. The criteria chosen included both log K ow values and BCF values, although it was suggested that BCF and BAF are more realistic measures of bioaccumulation than log K ow , as they are derived from animal studies. The chosen values agreed with the virtual elimination criteria set out by the Canadian Environmental Protection Act (CEPA) 1999 as well as United States Environmental Protection Agency (EPA) criteria. It was concluded that the bioaccumulation criteria for E2 planning will help Environment Canada ensure the protection of the environment from hazardous substances. 11 refs., 3 tabs., 5 figs

Inoculating Helianthus annuus (sunflower) grown in zinc and cadmium contaminated soils with plant growth promoting bacteria--effects on phytoremediation strategies.

Science.gov (United States)

Marques, Ana P G C; Moreira, Helena; Franco, Albina R; Rangel, António O S S; Castro, Paula M L

2013-06-01

Plant growth promoting bacteria (PGPR) may help reducing the toxicity of heavy metals to plants in polluted environments. In this work the effects of inoculating metal resistant and plant growth promoting bacterial strains on the growth of Helianthus annuus grown in Zn and Cd spiked soils were assessed. The PGPR strains Ralstonia eutropha (B1) and Chrysiobacterium humi (B2) reduced losses of weight in metal exposed plants and induced changes in metal bioaccumulation and bioconcentration - with strain B2 decreasing up to 67% Zn accumulation and by 20% Zn bioconcentration factor (BCF) in the shoots, up to 64% Zn uptake and 38% Zn BCF in the roots, and up to 27% Cd uptake and 27% Cd BCF in plant roots. The impact of inoculation on the bacterial communities in the rhizosphere of the plant was also assessed. Bacterial community diversity decreased with increasing levels of metal contamination in the soil, but in rhizosphere soil of plants inoculated with the PGPR strains, a higher bacterial diversity was kept throughout the experimental period. Inoculation of sunflower, particularly with C. humi (B2), appears to be an effective way of enhancing the short term stabilization potential of the plant in metal contaminated land, lowering losses in plant biomass and decreasing aboveground tissue contamination. Copyright © 2013 Elsevier Ltd. All rights reserved.

Bioconcentration of 14 C-Carbofuran and 14 C- Lindane in fresh water Tilapia Nilitica and the bioavailability of their residues to rats

International Nuclear Information System (INIS)

Aly, M.A.S.; Afifi, L.M.

1997-01-01

Tilapia Nilotica were exposed to 14 C- carbofuran (125 MUg/1) and 14 C - lindane (80 MUg/1) for 96 h. Uptake period followed by 8 days depuration period. The bioconcentration factor (BCF) for carbofuran reached 32.4 at 12 h and 82 for lindane at 48 h. The amount of 14 C-activity found in fish treated with 14 C - carbofuran after the uptake period showed the following descending order: viscera > remaining parts > gills > muscles. In case of 14 C - lindane treated fish the recovered amount followed the order; remaining parts> viscera > gills muscles. During the depuration period, carbofuran residues taken up by fish were eliminated in 2 phases, an initial rapid phase followed by a slower gradual one. However, the rate of elimination in case of lindane was much slower especially during the first 2 days. At the end of the depuration period (8 days), the muscles (edible portion) contained 10% and 58% of 14 C -activity in case of carbofuran and lindane treated groups, respectively. Both insecticides proved to be bioavailable when rats were fed treated fish. Of the administered dose, 44.1% and 53.0% were excreted in urine and feces case of 14 C-carbofuran while in case of 14 C - lindane it was 30.9% and 41.7% for urine and feces, respectively. 2 figs., 2 tabs

Bioconcentration factors and potential human health risks of heavy metals in cultivated Lentinus edodes in Chengdu, People's Republic of China.

Science.gov (United States)

Pei, Donghui; Xie, Han; Song, Haihai; Xu, Heng; Wu, Yumeng

2015-02-01

Lentinus edodes is one of the most popular edible mushrooms in the market. However, it contains heavy metals that are poisonous to humans even at trace concentrations. The concentrations and bioconcentration factors of five heavy metals in cultivated L. edodes in Chengdu were studied, and the potential health risks to local residents associated with the cultivated L. edodes consumption were evaluated. Total concentrations of cadmium (Cd), lead (Pb), chromium (Cr), arsenic (As), and mercury were determined in the fruiting bodies and the substrate from three agricultural areas. Fruiting bodies samples were collected at different growing times (2, 4, 6, and 8 days). The bioconcentration factors of heavy metals from the substrate to the fruiting bodies were estimated, and the potential health risks of local L. edodes were assessed. Because antioxidant enzymes can resist the creation of reactive oxygen species and defend against heavy metals, the activities of three antioxidant enzymes (superoxide dismutase, catalase, and peroxidase) in the fruiting bodies were also determined. A gradual change in heavy metal concentrations occurred across the growing time of the fruiting bodies. Cd transferred from the substrate to the fruiting bodies in larger concentrations than did Pb, Cr, and As. However, Chengdu residents were not exposed to significant health risks associated with consumption of local L. edodes. Nevertheless, more attention should be focused on children because of their higher sensitivity to metal pollutants.

Correlation and prediction of environmental properties of alcohol ethoxylate surfactants using the UNIFAC method

DEFF Research Database (Denmark)

Cheng, Hongyuan; Kontogeorgis, Georgios; Stenby, Erling Halfdan

2005-01-01

), the bioconcentration factor (BCF), and the toxicity. Kow values of alcohol ethoxylates are difficult to measure. Existing methods such as those in commercial software like ACD,ClogP and KowWin have not been applied to surfactants, and they fail for heavy alcohol ethoxylates (alkyl carbon numbers above 12). Thus...... and toxicity of alcohol ethoxylates are correlated with their Kow. The proposed approach can be extended to other families of nonionic surfactants....

Assessment of potential indigenous plant species for the phytoremediation of arsenic-contaminated areas of Bangladesh.

Science.gov (United States)

Mahmud, Rezwanul; Inoue, Naoto; Kasajima, Shin-Ya; Shaheen, Riffat

2008-01-01

Soil and water contaminated with arsenic (As) pose a major environmental and human health problem in Bangladesh. Phytoremediation, a plant-based technology, may provide an economically viable solution for remediating the As-polluted sites. The use of indigenous plants with a high tolerance and accumulation capacity for As may be a very convenient approach for phytoremediation. To assess the potential of native plant species for phytoremediation, plant and soil samples were collected from four As-contaminated (groundwater) districts in Bangladesh. The main criteria used for selecting plants for phytoremediation were high bioconcentration factors (BCFs) and translocation factors (TFs) of As. From the results of a screening of 49 plant species belonging to 29 families, only one species of fern (Dryopteris filix-mas), three herbs (Blumea lacera, Mikania cordata, and Ageratum conyzoides), and two shrubs (Clerodendrum trichotomum and Ricinus communis) were found to be suitable for phytoremediation. Arsenic bioconcentration and translocation factors > 1 suggest that these plants are As-tolerant accumulators with potential use in phytoextraction. Three floating plants (Eichhornia crassipes, Spirodela polyrhiza, and Azolla pinnata) and a common wetland weed (Monochoria vaginalis) also showed high BCF and TF values; therefore, these plants may be promising candidates for cleaningup As-contaminated surface water and wetland areas. The BCF of Oryza sativa, obtained from As-contaminated districts was > 1, which highlights possible food-chain transfer issues for As-contaminated areas in Bangladesh.

Lead (Pb Accumulation in Water, Sediment and Mussels (Hiatula chinensis from Pasir Panjang Coast, Lekok-Pasuruan

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Defri Yona

2016-10-01

Full Text Available This study attempted to evaluate Pb accumulation in the water, sediment and mussels (Hiatula chinensis from Lekok-Pasuruan. There were four sampling stations representing the study area: (1 urban areas, (2 water flow area from steam power plant (PLTU, (3 waste disposal area of PLTU, (4 fishing port. The average concentration of lead varied between stations in the water (0.279 ppm, sediment (0.423 ppm and mussels (0.427 ppm. Pearson`s correlation test shows strong relationship (p > 0.05 between Pb in the water, sediment and Hiatula chinensis. Mussels accumulation of lead from the sediment was assessed using bio-concentration factor (BCF and the result shows Hiatula chinensis is an accumulator of Pb (BCF > 1.

EXPERIMENTAL AND MONTE CARLO INVESTIGATIONS OF BCF-12 SMALL‑AREA PLASTIC SCINTILLATION DETECTORS FOR NEUTRON PINHOLE CAMERA.

Science.gov (United States)

Bielecki, J; Drozdowicz, K; Dworak, D; Igielski, A; Janik, W; Kulinska, A; Marciniak, L; Scholz, M; Turzanski, M; Wiacek, U; Woznicka, U; Wójcik-Gargula, A

2017-12-11

Plastic organic scintillators such as the blue-emitting BCF-12 are versatile and inexpensive tools. Recently, BCF-12 scintillators have been foreseen for investigation of the spatial distribution of neutrons emitted from dense magnetized plasma. For this purpose, small-area (5 mm × 5 mm) detectors based on BCF-12 scintillation rods and Hamamatsu photomultiplier tubes were designed and constructed at the Institute of Nuclear Physics. They will be located inside the neutron pinhole camera of the PF-24 plasma focus device. Two different geometrical layouts and approaches to the construction of the scintillation element were tested. The aim of this work was to determine the efficiency of the detectors. For this purpose, the experimental investigations using a neutron generator and a Pu-Be source were combined with Monte Carlo computations using the Geant4 code. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Phytoremediation of heavy metals from fly ash pond by Azolla caroliniana.

Science.gov (United States)

Pandey, Vimal Chandra

2012-08-01

Abundance of naturally growing Azolla caroliniana (water fern) on the surface of metal enriched fly ash (FA) pond reflects its toxitolerant characteristics. Results indicate the efficiency of A. caroliniana for phytoremediation of FA pond because of its higher bioconcentration factor. The metal concentration ranged from 175 to 538 and 86 to 753mgkg(-1) in roots and fronds, respectively. Bioconcentration factor (BCF) values of all metals in root and frond ranged from 1.7 to18.6 and 1.8 to 11.0, respectively, which were greater than one and indicates the metal accumulation potential of A. caroliniana. Translocation factor (TF) ranged from 0.37 to 1.4 for various heavy metals. The field result proved that A. caroliniana is a potential accumulator for the examined heavy metals and can be used for phytoremediation of FA pond. Copyright © 2012 Elsevier Inc. All rights reserved.

Uptake of polychlorinated biphenyls and organochlorine pesticides from soil and air into radishes (Raphanus sativus)

Energy Technology Data Exchange (ETDEWEB)

Mikes, Ondrej; Cupr, Pavel [RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk University, Kamenice 126/3, 625 00 Brno (Czech Republic); Trapp, Stefan [Department of Environmental Engineering, Technical University of Denmark, Miljoevej 113, DK-2800 Kgs. Lyngby (Denmark); Klanova, Jana [RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk University, Kamenice 126/3, 625 00 Brno (Czech Republic)], E-mail: klanova@recetox.muni.cz

2009-02-15

Uptake of organochlorine pesticides and polychlorinated biphenyls from soil and air into radishes was measured at a heavily contaminated field site. The highest contaminant concentrations were found for DDT and its metabolites, and for {beta}-hexachlorocyclohexane. Bioconcentration factor (BCF, defined as a ratio between the contaminant concentration in the plant tissue and concentration in soil) was determined for roots, edible bulbs and shoots. Root BCF values were constant and not correlated to log K{sub OW}. A negative correlation between BCF and log K{sub OW} was found for edible bulbs. Shoot BCF values were rather constant and varied between 0.01 and 0.22. Resuspended soil particles may facilitate the transport of chemicals from soil to shoots. Elevated POP concentrations found in shoots of radishes grown in the control plot support the hypothesis that the uptake from air was more significant for shoots than the one from soil. The uptake of POPs from air was within the range of theoretical values predicted from log K{sub OA}. - Uptake from air represented for majority of persistent organochlorines a dominant pathway into shoots while uptake from soil was dominant for roots.

KABAM Version 1.0 User's Guide and Technical Documentation - Appendix F -Description of Equations Used to Calculate the BCF, BAF, BMF, and BSAF Values

Science.gov (United States)

Describes equations for bioconcentration, bioaccumulation, biomagnification and biota-sediment accumulation factors used in KABAM V1.0. KABAM is a simulation model used to predict pesticide concentrations in aquatic regions for use in exposure assessments.

Evaluation of the cadmium and lead phytoextraction by castor bean (Ricinus communis L.) in hydroponics

Science.gov (United States)

Niu, Z. X.; Sun, L. N.

2017-06-01

Phytoextraction has been considered as an innovative method to remove toxic metals from soil; higher biomass plants such as castor bean (Ricinus communis L.) have already been considered as a hyperaccumulating candidate. In the present study, castor bean was used to accumulate the cadmium and lead in hydroponic culture, and the root exudates and biomass changes were analyzed. Results demonstrated that ratios of aerial biomass/ root biomass (AW/RW) in treatments declined with concentrations of Cd or Pb. Optical density (OD) at 190 nm and 280 nm of root exudates observed in Cd and Pb treatments were lower than the control. In single Cd or Pb treatments, bioconcentration factors (BCF) of Cd or Pb increased with time and decreased with concentrations, the highest BCFs appeared in Cd5 (14.36) and Pb50 (6.48), respectively. Cd-BCF or Pb-BCF showed positive correlations with AW/RW ratios and OD values, and they were negative correlated with Cd and Pb concentration. Results in this study may supply useful information for phytoremediation of soil contaminated with cadmium and lead in situ.

Toxic effects, bioconcentration and depuration of verapamil in the early life stages of common carp (Cyprinus carpio L.)

Czech Academy of Sciences Publication Activity Database

Steinbach, C.; Fedorova, G.; Prokeš, Miroslav; Grabicová, K.; Máchová, J.; Grabic, R.; Valentová, O.; Kocour Kroupová, H.

461-462, 461-462 (2013), s. 198-206 ISSN 0048-9697 Institutional support: RVO:68081766 Keywords : Bioconcentration * Embryo-larval test * Half-life time * Heart rate * Verapamil Subject RIV: GL - Fishing Impact factor: 3.163, year: 2013

Bioconcentration, bioaccumulation, and metabolism of pesticides in aquatic organisms.

Science.gov (United States)

Katagi, Toshiyuki

2010-01-01

The ecotoxicological assessment of pesticide effects in the aquatic environment should normally be based on a deep knowledge of not only the concentration of pesticides and metabolites found but also on the influence of key abiotic and biotic processes that effect rates of dissipation. Although the bioconcentration and bioaccumulation potentials of pesticides in aquatic organisms are conveniently estimated from their hydrophobicity (represented by log K(ow), it is still indispensable to factor in the effects of key abiotic and biotic processes on such pesticides to gain a more precise understanding of how they may have in the natural environment. Relying only on pesticide hydrophobicity may produce an erroneous environmental impact assessment. Several factors affect rates of pesticide dissipation and accumulation in the aquatic environment. Such factors include the amount and type of sediment present in the water and type of diet available to water-dwelling organisms. The particular physiological behavior profiles of aquatic organisms in water, such as capacity for uptake, metabolism, and elimination, are also compelling factors, as is the chemistry of the water. When evaluating pesticide uptake and bioconcentration processes, it is important to know the amount and nature of bottom sediments present and the propensity that the stuffed aquatic organisms have to absorb and process xenobiotics. Extremely hydrophobic pesticides such as the organochlorines and pyrethroids are susceptible to adsorb strongly to dissolved organic matter associated with bottom sediment. Such absorption reduces the bioavailable fraction of pesticide dissolved in the water column and reduces the probable ecotoxicological impact on aquatic organisms living the water. In contrast, sediment dweller may suffer from higher levels of direct exposure to a pesticide, unless it is rapidly degraded in sediment. Metabolism is important to bioconcentration and bioaccumulation processes, as is

Element composition of biota, water and sediment in the Forsmark area, Baltic Sea. Concentrations, bioconcentration factors and partitioning coefficients (Kd) of 48 elements

International Nuclear Information System (INIS)

Kumblad, Linda; Bradshaw, Clare

2008-08-01

In this study the elemental composition of biota, water and sediment from a shallow bay in the Forsmark region have been determined. The report presents data for 48 different elements (Al, As, Ba, Br, C, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Er, Eu, F, Fe, Gd, Hg, Ho, I, K, Li, Lu, Mg, Mn, N, Na, Nd, Ni, P, Pb, Pr, Ra, Rb, S, Se, Si, Sm, Tb, Th, Ti, Tm, V, Yb, Zn, Zr) in all major functional groups of the coastal ecosystem (phytoplankton, zooplankton, benthic microalgae, macroalgae, macrophytes, benthic herbivores, benthic filter feeders, benthic detrivores, planktivorous fish, benthic omnivorous fish, carnivorous fish, dissolved and particulate matter in the water and the sediment) during spring 2005. The overall aim of the study is to contribute to a better understanding of ecological properties and processes that govern uptake and transfer of trace elements, heavy-metals, radionuclides and other non-essential elements/contaminants in coastal environments of the Baltic Sea. In addition, the data was collected to provide site-specific Bioconcentration Factors (BCF), Biomagnification Factors (BMF), partitioning coefficients (K d ) and element ratios (relative to carbon) for use in ongoing SKB safety assessments. All these values, as well as the element concentration data from which they are derived, are presented here. As such, this is mainly a data report, although initial interpretations of the data also are presented and discussed. Reported data include element concentrations, CNP-stoichiometry, and multivariate data analysis. Elemental concentrations varied greatly between organisms and environmental components, depending on the function of the elements, and the habitat, ecosystem function, trophic level and morphology (taxonomy) of the organisms. The results show for instance that food intake and metabolism strongly influence the elemental composition of organisms. The three macrophytes had quite similar elemental composition (despite their taxonomic differences

Evaluation of the Sagittaria montevidensis Cham. & Schltdl. as a bioindicator and phytoextractor of toxic metals

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Edila Maria Kickhöfel Ferrer

2017-12-01

Full Text Available This study evaluated the bioindication and phytoremediation capacity of the aquatic macrophyte Sagittaria montevidensis by using it to assess the bioconcentration and translocation of heavy metals. A simple sampling was conducted at four sites in the region of Pelotas, southern Brazil, where plants, water and sediments were collected. The plants were subjected to nitric-perchloric acid digestion and the sediments underwent pseudo-total acid digestion. The determination of the elements Cr, Cu, Pb, Ni and Zn in the extracts was performed by flame atomic absorption spectrometry. Physicochemical tests were also carried out on water samples, including pH, electrical conductivity, chlorides, alkalinity, hardness and organic matter, and in sediment samples, moisture and organic matter content. The macrophyte study indicated a Bioconcentration Factor (BCF and a Translocation Factor (TF, especially for Ni. The results showed that the aquatic macrophyte species S. montevidensis has a phytoextraction capacity, mainly for Ni, and potentially for bioindication of Cu, Ni and Zn.

Bioconcentration of manganese and iron in Panaeoloideae Sing

NARCIS (Netherlands)

Stijve, T.; Blake, C.

1994-01-01

According to literature, the manganese content of most basidiomycetes fluctuates between 10 and 60 mg/kg, whereas the iron levels range from 100-500 mg/kg (both expressed on dry weight). The present authors report that bioconcentration of manganese is a distinguishing feature of the Panaeoloideae,

Bioaccumulation of pharmaceutically active compounds and endocrine disrupting chemicals in aquatic macrophytes: Results of hydroponic experiments with Echinodorus horemanii and Eichhornia crassipes.

Science.gov (United States)

Pi, N; Ng, J Z; Kelly, B C

2017-12-01

Information regarding the bioaccumulation behaviour of pharmaceutically active compounds (PhACs) and endocrine disrupting chemicals (EDCs) in aquatic plants is limited. The present study involved controlled hydroponic experiments to assess uptake and elimination rate constants (k u , k e ), bioconcentration factors (BCFs) and translocation factors (TFs) of several PhACs and EDCs in two aquatic macrophyte species, including one submerged species (Echinodorus horemanii) and one free-floating species (Eichhornia crassipes). The results revealed that the studied compounds are readily taken up in these aquatic plants. While bioconcentration factors (BCFs) and translocation factors (TFs) of the test compounds varied substantially, no discernible relationship with physicochemical properties such as octanol-water distribution coefficient (D ow ), membrane-water distribution coefficient (D mw ) and organic carbon-water partition coefficient (K oc ). Diphenhydramine and triclosan exhibited the highest degree of uptake and bioaccumulation potential. For example, the whole-plant BCF of triclosan in E. horemanii was 4390L/kg, while the whole-plant BCF of diphenhydramine in E. crassipes was 6130L/kg. BCFs of 17β-estradiol (E2), 17α-ethinylestradiol (EE2), estrone (E1) and bisphenol A (BPA) were relatively low (2-150L/kg). BCFs were generally higher in free-floating aquatic macrophyte species compared to the submerged species. For the free-floating species, E. crassipes, the majority of PhACs and EDCs were more allocated in roots compared to leaves, with TFs1). The study findings may be useful for design and implementation of phytoremediation systems, as well as aid future modeling and risk assessment initiatives for these emerging organic contaminants. Copyright © 2017 Elsevier B.V. All rights reserved.

Element composition of biota, water and sediment in the Forsmark area, Baltic Sea. Concentrations, bioconcentration factors and partitioning coefficients (K{sub d}) of 48 elements

Energy Technology Data Exchange (ETDEWEB)

Kumblad, Linda; Bradshaw, Clare (Dept. of Systems Ecology, Stockholm Univ. (Sweden))

2008-08-15

In this study the elemental composition of biota, water and sediment from a shallow bay in the Forsmark region have been determined. The report presents data for 48 different elements (Al, As, Ba, Br, C, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Er, Eu, F, Fe, Gd, Hg, Ho, I, K, Li, Lu, Mg, Mn, N, Na, Nd, Ni, P, Pb, Pr, Ra, Rb, S, Se, Si, Sm, Tb, Th, Ti, Tm, V, Yb, Zn, Zr) in all major functional groups of the coastal ecosystem (phytoplankton, zooplankton, benthic microalgae, macroalgae, macrophytes, benthic herbivores, benthic filter feeders, benthic detrivores, planktivorous fish, benthic omnivorous fish, carnivorous fish, dissolved and particulate matter in the water and the sediment) during spring 2005. The overall aim of the study is to contribute to a better understanding of ecological properties and processes that govern uptake and transfer of trace elements, heavy-metals, radionuclides and other non-essential elements/contaminants in coastal environments of the Baltic Sea. In addition, the data was collected to provide site-specific Bioconcentration Factors (BCF), Biomagnification Factors (BMF), partitioning coefficients (K{sub d}) and element ratios (relative to carbon) for use in ongoing SKB safety assessments. All these values, as well as the element concentration data from which they are derived, are presented here. As such, this is mainly a data report, although initial interpretations of the data also are presented and discussed. Reported data include element concentrations, CNP-stoichiometry, and multivariate data analysis. Elemental concentrations varied greatly between organisms and environmental components, depending on the function of the elements, and the habitat, ecosystem function, trophic level and morphology (taxonomy) of the organisms. The results show for instance that food intake and metabolism strongly influence the elemental composition of organisms. The three macrophytes had quite similar elemental composition (despite their taxonomic

Comparison of arsenate and cadmium toxicity in a freshwater amphipod (Gammarus pulex)

International Nuclear Information System (INIS)

Vellinger, Céline; Parant, Marc; Rousselle, Philippe; Immel, Françoise

2012-01-01

Cadmium is largely documented on freshwater organisms while arsenic, especially arsenate, is rarely studied. The kinetic of the LC50s values for both metals was realized on Gammarus pulex. Physiological [i.e. metal concentration in body tissues, bioconcentration factor (BCF)] effects and behavioural responses (via pleopods beats) were investigated after 240-h exposure. Arsenate LC50 value was 100 fold higher than Cd-LC50 value after 240-h exposure, while concentrations in gammarids were similar for both metals at their respective LC50s. BCF decreased with increasing cadmium concentration while BCF remained stable with increasing arsenate concentration. Moreover, BCF was between 148 and 344 times lower for arsenate than cadmium. A significant hypoventilation was observed for cadmium concentrations exceeding or close to the 240h-LC50 Cd , while gammarids hyperventilated for the lowest arsenate concentrations and hypoventilated for the highest arsenate concentrations. We discussed the relationships between potential action mechanisms of these two metals and observed results. - Highlights: ► First study of arsenate toxicity in a Crustacean gammarid. ► Specific toxicological and behavioural responses to AsV and Cd contamination. ► Each metal led to specific-action mechanisms. ► Different energetic reallocation could explain specific behavioural responses. - This study brings to light the potential relationship between toxicological effects and behavioural responses of G. pulex exposed at both Cadmium and Arsenate.

A flow-through passive dosing system for continuously supplying aqueous solutions of hydrophobic chemicals to bioconcentration and aquatic toxicity tests

DEFF Research Database (Denmark)

Adolfsson-Erici, Margaretha; Åkerman, Gun; Jahnke, Annika

2012-01-01

A continuous supply of water with defined stable concentrations of hydrophobic chemicals is a requirement in a range of laboratory tests such as the OECD 305 protocol for determining the bioconcentration factor in fish. Satisfying this requirement continues to be a challenge, particularly for hyd...

Bioaccumulation of toxic metals (Cd and Cu) by Groenlandia densa (L.) Fourr.

Science.gov (United States)

Kara, Yesim; Zeytunluoglu, Ali

2007-12-01

In this study, Groenlandia densa (L.) Fourr. (opposite-leaved pondweed), was exposed to prepared stock solution of cadmium and copper with 1.0, 3.0, 5.0 and 7.0 mg L(-1) concentration in certain periods (24, 48, 72 and 96 h) and changing amount of accumulation of plants in depending on time and concentration was measured by atomic absorption spectrophotometer. The results show that under experimental conditions, G. densa (L.) Fourr. proved to be a good accumulator of Cd and Cu. Removal of the metals from solution was fast in the first 4 days. The accumulation of Cd and Cu increased with the initial concentration and also with time. The highest concentrations of each trace element accumulated in opposite-leaved pondweed tissues were 1,955 mug Cd g(-1), 6,135 microg Cu g(-1) after 4 days. The maximum values of bioconcentration factor (BCF) were found for Cd and Cu 724 and 1,669, respectively. BCF values for Cd and Cu increased with time.

Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water.

Science.gov (United States)

Ellison, Michael B; de Nys, Rocky; Paul, Nicholas A; Roberts, David A

2014-01-01

The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation of metals. The experiments used Ash Dam water from Tarong power station in Queensland, which is contaminated by multiple metals (Al, Cd, Ni and Zn) and metalloids (As and Se) in excess of Australian water quality guidelines. All species had consistent growth rates in Ash Dam water, despite significant differences in their growth rates in "clean" water. A species isolated from the Ash Dam water itself was not better suited to the bioremediation of that waste water. While there were differences in the temporal pattern of the bioconcentration of metals by the three species, over the course of the experiment, all three species bioconcentrated the same elements preferentially and to a similar extent. All species bioconcentrated metals (Cu, Mn, Ni, Cd and Zn) more rapidly than metalloids (As, Mo and Se). Therefore, bioremediation in situ will be most rapid and complete for metals. Overall, all three species of freshwater macroalgae had the ability to grow in waste water and bioconcentrate elements, with a consistent affinity for the key metals that are regulated by Australian and international water quality guidelines. Together, these characteristics make Oedogonium a clear target for scaled bioremediation programs across a range of geographic regions.

Growth and metal bioconcentration by conspecific freshwater macroalgae cultured in industrial waste water

Directory of Open Access Journals (Sweden)

Michael B. Ellison

2014-05-01

Full Text Available The bioremediation of industrial waste water by macroalgae is a sustainable and renewable approach to the treatment of waste water produced by multiple industries. However, few studies have tested the bioremediation of complex multi-element waste streams from coal-fired power stations by live algae. This study compares the ability of three species of green freshwater macroalgae from the genus Oedogonium, isolated from different geographic regions, to grow in waste water for the bioremediation of metals. The experiments used Ash Dam water from Tarong power station in Queensland, which is contaminated by multiple metals (Al, Cd, Ni and Zn and metalloids (As and Se in excess of Australian water quality guidelines. All species had consistent growth rates in Ash Dam water, despite significant differences in their growth rates in “clean” water. A species isolated from the Ash Dam water itself was not better suited to the bioremediation of that waste water. While there were differences in the temporal pattern of the bioconcentration of metals by the three species, over the course of the experiment, all three species bioconcentrated the same elements preferentially and to a similar extent. All species bioconcentrated metals (Cu, Mn, Ni, Cd and Zn more rapidly than metalloids (As, Mo and Se. Therefore, bioremediation in situ will be most rapid and complete for metals. Overall, all three species of freshwater macroalgae had the ability to grow in waste water and bioconcentrate elements, with a consistent affinity for the key metals that are regulated by Australian and international water quality guidelines. Together, these characteristics make Oedogonium a clear target for scaled bioremediation programs across a range of geographic regions.

The effects of dissolved organic matter and feeding on bioconcentration and oxidative stress of ethylhexyl dimethyl p-aminobenzoate (OD-PABA) to crucian carp (Carassius auratus).

Science.gov (United States)

Ma, Binni; Lu, Guanghua; Yang, Haohan; Liu, Jianchao; Yan, Zhenhua; Nkoom, Matthew

2018-03-01

Bioconcentration of UV filters in organisms is an important indicator for the assessment of environmental hazards. However, bioconcentration testing rarely accounts for the influence of natural aquatic environmental factors. In order to better assess the ecological risk of organic UV filters (OUV-Fs) in an actual water environment, this study determined the influences of dissolved organic matter (DOM) (0, 1, 10, and 20 mg/L) and feeding (0, 0.5, 1, and 2% body weight/d) on bioconcentration of ethylhexyl dimethyl p-aminobenzoate (OD-PABA) in various tissues of crucian carp (Carassius auratus). Moreover, oxidative stress in the fish liver caused by the OD-PABA was also investigated by measuring activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST), and levels of glutathione (GSH) and malondialdehyde (MDA). The bioconcentration of OD-PABA in the fish tissues was significantly decreased with the presence of DOM indicating a reduction of OD-PABA bioavailability caused by DOM. The bioconcentration factors (BCFs) decreased by 28.00~50.93% in the muscle, 72.67~96.74% in the gill, 37.84~87.72% in the liver, and 10.32~79.38% in the kidney at different DOM concentrations compared to those of the non-DOM treatments. Significant changes in SOD, CAT, GST, GSH, and MDA levels were found in the DOM- and OD-PABA-alone treatments. However, there were no significant differences in the SOD, CAT, GST, and MDA levels found when co-exposure to OD-PABA and DOM. Feeding led to lower OD-PABA concentrations in the fish tissues, and the concentrations were decreased with increasing feeding ratios. BCFs in various tissues reduced by 39.75~72.52% in the muscle, 56.86~79.73% in the gill, 66.41~87.50% in the liver, and 75.88~89.10% in the kidney, respectively. In the unfed treatments, the levels of SOD and MDA were significantly higher than those of the fed ones while GST and GSH levels were remarkably inhibited indicating the enhanced effect of starvation

Bioconcentration of manganese and iron in Panaeoloideae Sing

OpenAIRE

Stijve, T.; Blake, C.

1994-01-01

According to literature, the manganese content of most basidiomycetes fluctuates between 10 and 60 mg/kg, whereas the iron levels range from 100-500 mg/kg (both expressed on dry weight). The present authors report that bioconcentration of manganese is a distinguishing feature of the Panaeoloideae, as demonstrated by the analysis of 44 collections representing 15 taxons. Carpophores generally contain between 250 and 2500 mg/kg on dry weight, and, with the notable exception of Panaeolus semiova...

Bioaccumulation and rhizofiltration potential of Pistia stratiotes L. for mitigating water pollution in the Egyptian wetlands.

Science.gov (United States)

Galal, Tarek M; Eid, Ebrahem M; Dakhil, Mohammed A; Hassan, Loutfy M

2018-04-16

The bioaccumulation and rhizofiltration potential of P. stratiotes for heavy metals were investigated to mitigate water pollution in the Egyptian wetlands. Plant and water samples were collected monthly through nine quadrats equally distributed along three sites at Al-Sero drain in Giza Province. The annual mean of the shoot biomass was 10 times that of the root. The concentrations of shoot heavy metals fell in the order: Fe < Mn < Cr < Pb < Cu < Zn < Ni < Co < Cd, while that of the roots were: Fe < Mn < Cr < Pb < Zn < Ni < Co < Cu < Cd. The bio-concentration factor (BCF) of most investigated heavy metals, except Cr and Pb, was greater than 1000, while the translocation factor (TF) of most investigated metals, except Pb and Cu, did not exceed one. The rhizofiltration potential (RP) of heavy metals was higher than 1000 for Fe, and 100 for Cr, Pb and Cu. Significant positive correlations between Fe and Cu in water with those in plant roots and leaves, respectively were recorded, which, in addition to the high BCF and RP, indicate the potential use of P. stratiotes in mitigating these toxic metals.

Perchlorate in seawater

Energy Technology Data Exchange (ETDEWEB)

Martinelango, P. Kalyani [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 (United States); Tian Kang [Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX 79409 (United States); Dasgupta, Purnendu K. [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 (United States)]. E-mail: Sandyd@ttu.edu

2006-05-10

There has been no reliable published data on the presence of perchlorate in seawater. Seaweeds are among the most important plant life in the ocean and are good sources of iodine and have been widely used as food and nutritional supplement. Perchlorate is known to inhibit the transport of iodide by the sodium iodide symporter (NIS), present e.g., in the thyroid and mammary glands. With perchlorate being increasingly detected in drinking water, milk and various other foods, increasing the iodide intake through inexpensive natural supplements may be an attractive solution for maintaining iodine assimilation. We report here measurable concentrations of perchlorate in several samples of seawater (detectable in about half the samples analyzed). We also report the iodide and perchlorate concentrations of 11 different species of seaweed and the corresponding bioconcentration factors (BCF) for perchlorate and iodide, relative to the seawater from which they were harvested. All seaweed samples came from the same region, off the coast of Northeastern Maine. Concentrations of iodide and perchlorate in four seawater samples collected from the region near harvest time were 30 {+-} 11 and 0.16 {+-} 0.084 {mu}g l{sup -1}, respectively. Concentrations of both iodide and perchlorate varied over a wide range for different seaweed species; iodide ranging from 16 to 3134 mg kg{sup -1} and perchlorate from 0.077 to 3.2 mg kg{sup -1}. The Laminaria species had the highest iodide concentration; Laminaria digitata is the seaweed species most commonly used in the kelp tablets sold in health food stores. Our sample of L. digitata contained 3134 {+-} 15 mg iodide/kg dry weight. The BCF varied widely for different species, with Laminaria species concentrating iodide preferentially over perchlorate. The iodide BCF (BCF{sub i}) to perchlorate BCF (BCF{sub p}) quotient ranged from 0.66 to 53; L. digitata and L. saccarina having a BCF{sub i}/BCF{sub p} value of 45 and 53, respectively, far

Perchlorate in seawater

International Nuclear Information System (INIS)

Martinelango, P. Kalyani; Tian Kang; Dasgupta, Purnendu K.

2006-01-01

There has been no reliable published data on the presence of perchlorate in seawater. Seaweeds are among the most important plant life in the ocean and are good sources of iodine and have been widely used as food and nutritional supplement. Perchlorate is known to inhibit the transport of iodide by the sodium iodide symporter (NIS), present e.g., in the thyroid and mammary glands. With perchlorate being increasingly detected in drinking water, milk and various other foods, increasing the iodide intake through inexpensive natural supplements may be an attractive solution for maintaining iodine assimilation. We report here measurable concentrations of perchlorate in several samples of seawater (detectable in about half the samples analyzed). We also report the iodide and perchlorate concentrations of 11 different species of seaweed and the corresponding bioconcentration factors (BCF) for perchlorate and iodide, relative to the seawater from which they were harvested. All seaweed samples came from the same region, off the coast of Northeastern Maine. Concentrations of iodide and perchlorate in four seawater samples collected from the region near harvest time were 30 ± 11 and 0.16 ± 0.084 μg l -1 , respectively. Concentrations of both iodide and perchlorate varied over a wide range for different seaweed species; iodide ranging from 16 to 3134 mg kg -1 and perchlorate from 0.077 to 3.2 mg kg -1 . The Laminaria species had the highest iodide concentration; Laminaria digitata is the seaweed species most commonly used in the kelp tablets sold in health food stores. Our sample of L. digitata contained 3134 ± 15 mg iodide/kg dry weight. The BCF varied widely for different species, with Laminaria species concentrating iodide preferentially over perchlorate. The iodide BCF (BCF i ) to perchlorate BCF (BCF p ) quotient ranged from 0.66 to 53; L. digitata and L. saccarina having a BCF i /BCF p value of 45 and 53, respectively, far greater than a simple anion exchange process

Solid-phase microextraction for bioconcentration studies according to OECD TG 305

Energy Technology Data Exchange (ETDEWEB)

Duering, Rolf-Alexander; Boehm, Leonard [Land Use and Nutrition (IFZ) Justus Liebig University Giessen, Institute of Soil Science and Soil Conservation, Research Centre for BioSystems, Giessen (Germany); Schlechtriem, Christian [Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Schmallenberg (Germany)

2012-12-15

An important aim of the European Community Regulation on chemicals and their safe use is the identification of (very) persistent, (very) bioaccumulative, and toxic substances. In other regulatory chemical safety assessments (pharmaceuticals, biocides, pesticides), the identification of such (very) persistent, (very) bioaccumulative, and toxic substances is of increasing importance. Solid-phase microextraction is especially capable of extracting total water concentrations as well as the freely dissolved fraction of analytes in the water phase, which is available for bioconcentration in fish. However, although already well established in environmental analyses to determine and quantify analytes mainly in aqueous matrices, solid-phase microextraction is still a rather unusual method in regulatory ecotoxicological research. Here, the potential benefits and drawbacks of solid-phase microextraction are discussed as an analytical routine approach for aquatic bioconcentration studies according to OECD TG 305, with a special focus on the testing of hydrophobic organic compounds characterized by log K{sub OW}> 5. (orig.)

Accumulation of elements by edible mushroom species: part I. Problem of trace element toxicity in mushrooms.

Science.gov (United States)

Mleczek, Mirosław; Siwulski, Marek; Stuper-Szablewska, Kinga; Rissmann, Iwona; Sobieralski, Krzysztof; Goliński, Piotr

2013-01-01

The aim of this study was to evaluate Cd, Co, Cu, Hg, Ni, Pb, Sr and Zn accumulation in six edible mushroom species and to assess their risk and benefits to human consumers. Mushrooms (Leccinium aurantiacum, Xerocomus badius, Lactarius deliciosus, Boletus edulis, Cantharellus cibarius and Suillus luteus) were collected from selected regions of Poland during 1990-2010. The highest diversity between studied mushroom species was observed in terms of Cu and Zn accumulation. Significant differences in the accumulation efficiency were found among the six mushroom species examined. The most efficient were Boletus edulis (Cd and Hg), Suillus luteus (Cu and Sr), and Lactarius deliciosus (Pb and Zn). In the case of Co and Ni, the most effective were Xerocomus badius and Leccinium aurantiacum, respectively. The calculated bioconcentration factor (BCF) values of Cd, Cu, Hg, Sr and Zn were > 1 for all species in this study while Co, Ni and Pb usually were bioexcluded (BCF luteus collected in Poland is safe and this finding largely agrees with results from recent studies by other authors.

Uptake of metals and metalloids by Conyza canadensis L. from a thermoelectric power plant landfill

Directory of Open Access Journals (Sweden)

Vukojević Vesna

2016-01-01

Full Text Available Fourteen metals and metalloids were determined in Conyza canadensis L. harvested from the fly ash landfill of the thermoelectric power plant “Kolubara” (Serbia. Fly ash samples were collected together with the plant samples and subjected to sequential extraction according to the three-step sequential extraction scheme proposed by the Community Bureau of Reference (BCR; now the Standards, Measurements and Testing Program. The contents of metals and metalloids were determined by inductively coupled plasma optical emission spectrometry (ICP-OES in plant root and the aboveground part and correlated with their contents in the fly ash samples. The bioconcentration factor (BCF and translocation factors (TF were calculated to access uptake of metals from fly ash and their translocation to the aboveground part. Results regarding As revealed that fly ash samples in the proximity of the active cassette had higher amounts of the element. Principal component analysis (PCA showed that As had no impact on the classification of plant parts. BCF for As ranged from 1.44 to 23.8 and varied, depending on the investigated area; TF for As ranged from 0.43 to 2.61, indicating that the plant translocated As from root to shoot. In addition to As, Conyza canadensis L. exhibited efficient uptake of other metals from fly ash. According to the calculated BCF and TF, the plant retained Al, Fe and Cr in the root and translocated Zn, Cd, Cu and As from root to shoot in the course of the detoxifying process. [Projekat Ministarstva nauke Republike Srbije, br. 172030 i br. 172017

Evidence of lead biomagnification in invertebrate predators from laboratory and field experiments

International Nuclear Information System (INIS)

Rubio-Franchini, Isidoro; Rico-Martinez, Roberto

2011-01-01

This report includes atomic absorption data from water column, elutriates and zooplankton that demonstrate that lead biomagnifies at El Niagara reservoir, Mexico. Results include field data (bioaccumulation factors) (BAFs) and laboratory data (bioconcentration factors) (BCFs). Two findings: high BAFs for invertebrate predator like Acanthocyclops robustus, Asplanchna brightwellii, Culex sp. larvae, and Hyalella azteca, compared to grazer species Moina micrura and Simocephalus vetulus; low BCF's found for some predators, suggested that lead biomagnifications were taking place. The presence of Moina micrura in the gut of Asplanchna allowed us to design experiments where A. brightwellii was fed lead-exposed M. micrura neonates. The BAF of Asplanchna was 123,684, BCF was 490. Asplanchna individuals fed exposed Moina had 13.31 times more lead than Asplanchna individuals just exposed 48-h to lead, confirming that lead biomagnification occurs. Results of two fish species showed no lead biomagnification, suggesting that lead biomagnification might be restricted to invertebrate predators. - Highlights: → Study shows lead biomagnification evidence in reservoirs where top predators are invertebrates. → Study discusses why in previous studies lead biomagnifications were not detected. → Evidence of biomagnification comes from field and laboratory studies. - This study shows evidence (from field and laboratory experiments) of lead biomagnification in a freshwater reservoir where the main predators are invertebrates.

The effect of pH on the bioconcentration and toxicity of weak organic electrolytes

DEFF Research Database (Denmark)

Rendal, Cecilie

to the bioconcentration of ionizing organic compounds showed that this fraction cannot safely be overlooked. The work presented in this thesis suggests that the standard test procedures used to test toxicity and bioconcentration are not sufficient to fully illuminate the ecotoxicity of ionizing organic compounds unless......Many of the compounds in use today have ionizing properties. Investigations have shown that around half of the compounds preregistered for REACH and over 70% of all pharmaceuticals are ionizing organic compounds. These compounds may pose a risk when they are released into the environment....... Ionization, however, complicates the environmental risk assessment of these compounds because the uptake processes of the neutral fraction differ from the processes of the ionized fraction. Acids are increasingly neutral at pH levels below the pKa while bases are increasingly neutral at pH levels above the p...

Mosses as an integrating tool for monitoring PAH atmospheric deposition: comparison with total deposition and evaluation of bioconcentration factors. A year-long case-study.

Science.gov (United States)

Foan, Louise; Domercq, Maria; Bermejo, Raúl; Santamaría, Jesús Miguel; Simon, Valérie

2015-01-01

Polycyclic aromatic hydrocarbon (PAH) atmospheric deposition was evaluated at a remote site in Northern Spain using moss biomonitoring with Hylocomium splendens (Hedw.) Schimp., and by measuring the total deposition fluxes of PAHs. The year-long study allowed seasonal variations of PAH content in mosses to be observed, and these followed a similar trend to those of PAH fluxes in total deposition. Generally, atmospheric deposition of PAHs is greater in winter than in summer, due to more PAH emissions from domestic heating, less photoreactivity of the compounds, and intense leaching of the atmosphere by wet deposition. However, fractionation of these molecules between the environmental compartments occurs: PAH fluxes in total deposition and PAH concentrations in mosses are correlated with their solubility (r=0.852, pPAH fluxes can be estimated with moss biomonitoring data if the bioconcentration or 'enriching' factors are known. Copyright © 2014 Elsevier Ltd. All rights reserved.

Plant Uptake of Organic Pollutants from Soil: A Critical Review ofBioconcentration Estimates Based on Modelsand Experiments

Energy Technology Data Exchange (ETDEWEB)

McKone, Thomas E.; Maddalena, Randy L.

2007-01-01

The role of terrestrial vegetation in transferring chemicals from soil and air into specific plant tissues (stems, leaves, roots, etc.) is still not well characterized. We provide here a critical review of plant-to-soil bioconcentration ratio (BCR) estimates based on models and experimental data. This review includes the conceptual and theoretical formulations of the bioconcentration ratio, constructing and calibrating empirical and mathematical algorithms to describe this ratio and the experimental data used to quantify BCRs and calibrate the model performance. We first evaluate the theoretical basis for the BCR concept and BCR models and consider how lack of knowledge and data limits reliability and consistency of BCR estimates. We next consider alternate modeling strategies for BCR. A key focus of this evaluation is the relative contributions to overall uncertainty from model uncertainty versus variability in the experimental data used to develop and test the models. As a case study, we consider a single chemical, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and focus on variability of bioconcentration measurements obtained from 81 experiments with different plant species, different plant tissues, different experimental conditions, and different methods for reporting concentrations in the soil and plant tissues. We use these observations to evaluate both the magnitude of experimental variability in plant bioconcentration and compare this to model uncertainty. Among these 81 measurements, the variation of the plant/soil BCR has a geometric standard deviation (GSD) of 3.5 and a coefficient of variability (CV-ratio of arithmetic standard deviation to mean) of 1.7. These variations are significant but low relative to model uncertainties--which have an estimated GSD of 10 with a corresponding CV of 14.

Influence of natural dissolved organic carbon on the bioavailability of mercury to a freshwater alga

International Nuclear Information System (INIS)

Gorski, P.R.; Armstrong, D.E.; Hurley, J.P.; Krabbenhoft, D.P.

2008-01-01

Bioavailability of mercury (Hg) to Selenastrum capricornutum was assessed in bioassays containing field-collected freshwater of varying dissolved organic carbon (DOC) concentrations. Bioconcentration factor (BCF) was measured using stable isotopes of methylmercury (MeHg) and inorganic Hg(II). BCFs for MeHg in low-DOC lake water were significantly larger than those in mixtures of lake water and high-DOC river water. The BCF for MeHg in rainwater (lowest DOC) was the largest of any treatment. Rainwater and lake water also had larger BCFs for Hg(II) than river water. Moreover, in freshwater collected from several US and Canadian field sites, BCFs for Hg(II) and MeHg were low when DOC concentrations were >5 mg L -1 . These results suggest high concentrations of DOC inhibit bioavailability, while low concentrations may provide optimal conditions for algal uptake of Hg. However, variability of BCFs at low DOC indicates that DOC composition or other ligands may determine site-specific bioavailability of Hg. - Bioavailability of mercury to an alga was greatest at low concentrations of natural dissolved organic carbon and inhibited at high concentrations of natural dissolved organic carbon

Bio-remediation of Pb and Cd polluted soils by switchgrass: A case study in India.

Science.gov (United States)

Arora, Kalpana; Sharma, Satyawati; Monti, Andrea

2016-01-01

In the present study bioremediation potential of a high biomass yielding grass, Panicum virgatum (switchgrass), along with plant associated microbes (AM fungi and Azospirillum), was tested against lead and cadmium in pot trials. A pot trial was set up in order to evaluate bioremediation efficiency of P. virgatum in association with PAMs (Plant Associated Microbes). Growth parameters and bioremediation potential of endomycorrhizal fungi (AMF) and Azospirillum against different concentrations of Pb and Cd were compared. AM fungi and Azospirillum increased the root length, branches, surface area, and root and shoot biomass. The soil pH was found towards neutral with AMF and Azospirillum inoculations. The bioconcentration factor (BCF) for Pb (12 mg kg(-1)) and Cd (10 mg kg(-1)) were found to be 0.25 and 0.23 respectively and translocation index (Ti) was 17.8 and 16.7 respectively (approx 45% higher than control). The lower values of BCF and Ti, even at highest concentration of Pb and Cd, revealed the capability of switchgrass of accumulating high concentration of Pb and Cd in the roots, while preventing the translocation of Pb and Cd to aerial biomass.

Toxicity and uptake of cyclic nitramine explosives in ryegrass Lolium perenne

International Nuclear Information System (INIS)

Rocheleau, Sylvie; Lachance, Bernard; Kuperman, Roman G.; Hawari, Jalal; Thiboutot, Sonia; Ampleman, Guy; Sunahara, Geoffrey I.

2008-01-01

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are cyclic nitramines used as explosives. Their ecotoxicities have been characterized incompletely and little is known about their accumulation potential in soil organisms. We assessed the toxicity and uptake of these explosives in perennial ryegrass Lolium perenne L. exposed in a Sassafras sandy loam (SSL) or in a sandy soil (DRDC, CL-20 only) containing contrasting clay contents (11% and 0.3%, respectively). A 21-d exposure to RDX, HMX or CL-20 in either soil had no adverse effects on ryegrass growth. RDX and HMX were translocated to ryegrass shoots, with bioconcentration factors (BCF) of up to 15 and 11, respectively. In contrast, CL-20 was taken up by the roots (BCF up to 19) with no translocation to the shoots. These studies showed that RDX, HMX, and CL-20 can accumulate in plants and may potentially pose a risk of biomagnification across the food chain. - Cyclic nitramine explosives accumulate in perennial ryegrass and exhibit distinct uptake patterns

Phytoextraction of trace elements by water hyacinth in contaminated area of gold mine tailing.

Science.gov (United States)

Romanova, Tamara E; Shuvaeva, Olga V; Belchenko, Ludmila A

2016-01-01

The ability of water hyacinth (Eichhornia crassipes) to uptake Ag, Ba, Cd, Mo, and Pb from waters in gold mine tailing area was studied. All experiments were carried out in the field conditions without using of model system. Bioconcentration (BCF) and translocation factors (TF) as well as elements accumulation by plant in different points of tailings-impacted area were evaluated. It has been shown that water hyacinth demonstrates high ability to accumulate Mo, Pb, and Ba with BCF values 24,360 ± 3600, 18,800 ± 2800 and 10,040 ± 1400, respectively and is efficient in translocation of Mo and Cd. The general trend of the plant accumulation ability in relation to the studied elements corresponds to their concentration in the medium. As the distance from tailings increases, concentration of Ag, Ba and Pb in plant decreases more clearly than that of Cd, while the amount of Mo accumulated by plant doesn't drop significantly in accordance with its concentration in water. Under the conditions of the confluence of river Ur and drainage stream Ba and Ag can be considered as potential candidates for phytomining.

Toxicity and uptake of cyclic nitramine explosives in ryegrass Lolium perenne

Energy Technology Data Exchange (ETDEWEB)

Rocheleau, Sylvie; Lachance, Bernard [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada); Kuperman, Roman G. [Edgewood Chemical Biological Center, 5183 Blackhawk Road, Aberdeen Proving Ground, MD 21010-5424 (United States); Hawari, Jalal [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada); Thiboutot, Sonia; Ampleman, Guy [Defense Research and Development Canada, 2459 Pie IX Boulevard, Val Belair, Quebec G3J 1X5 (Canada); Sunahara, Geoffrey I. [Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2 (Canada)], E-mail: geoffrey.sunahara@cnrc-nrc.gc.ca

2008-11-15

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) are cyclic nitramines used as explosives. Their ecotoxicities have been characterized incompletely and little is known about their accumulation potential in soil organisms. We assessed the toxicity and uptake of these explosives in perennial ryegrass Lolium perenne L. exposed in a Sassafras sandy loam (SSL) or in a sandy soil (DRDC, CL-20 only) containing contrasting clay contents (11% and 0.3%, respectively). A 21-d exposure to RDX, HMX or CL-20 in either soil had no adverse effects on ryegrass growth. RDX and HMX were translocated to ryegrass shoots, with bioconcentration factors (BCF) of up to 15 and 11, respectively. In contrast, CL-20 was taken up by the roots (BCF up to 19) with no translocation to the shoots. These studies showed that RDX, HMX, and CL-20 can accumulate in plants and may potentially pose a risk of biomagnification across the food chain. - Cyclic nitramine explosives accumulate in perennial ryegrass and exhibit distinct uptake patterns.

Susceptibility of riparian wetland plants to perfluorooctanoic acid (PFOA) accumulation.

Science.gov (United States)

Mudumbi, J B N; Ntwampe, S K O; Muganza, M; Okonkwo, J O

2014-01-01

As plants have been shown to accumulate organic compounds from contaminated sediments, there is a potential for long-lasting ecological impact as a result of contaminant accumulation in riparian areas of wetlands, particularly the accumulation of non-biodegradable contaminants such as perfluorooctanoic acid (PFOA). In this study, commonly found riparian wetland plants including reeds, i.e., Xanthium strumarium, Phragmites australis, Schoenoplectus corymbosus, Ruppia maritime; Populus canescens, Polygonum salicifolium, Cyperus congestus; Persicaria amphibian, Ficus carica, Artemisia schmidtiana, Eichhornia crassipes, were studied to determine their susceptibility to PFOA accumulation from PFOA contaminated riparian sediment with a known PFOA concentration, using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The bioconcentration factor (BCF) indicated that the plants affinity to PFOA accumulation was; E. crassipes, > P. sali-cifolium, > C. congestus, > P. x canescens, > P. amphibian, > F. carica, > A. schmidtiana, > X. strumarium,> P. australis, > R. maritime, > S. corymbosus. The concentration of PFOA in the plants and/or reeds was in the range 11.7 to 38 ng/g, with a BCF range of 0.05 to 0.37. The highest BCF was observed in sediment for which its core water had a high salinity, total organic carbon and a pH which was near neutral. As the studied plants had a higher affinity for PFOA, the resultant effect is that riparian plants such as E. crassipes, X. strumarium, and P. salicifolium, typified by a fibrous rooting system, which grow closer to the water edge, exacerbate the accumulation of PFOA in riparian wetlands.

[Mercury in three species of Suillus mushroom from some sites in Poland].

Science.gov (United States)

Mielewska, Dominika; Stefańska, Aleksandra; Wenta, Justyna; Mazur, Michalina; Bielawski, Leszek; Danisiewicz, Dorota; Dryzałowska, Anna; Falandysz, Jerzy

2008-01-01

Total mercury content have been determined in fruiting bodies of Variegated Bolete (Suillus variegates), European Cow Bolete (S. bovinus) and Slippery Jack (S. luteus) and in underlying to mushroom's surface layer of soil substrate collected from several spatially distant one from another sites in Poland. All three Suillus mushroom species independent of the site characterized were by small mercury content. The arithmetic mean values of mercury concentration in caps and stipes, respectively, were: 0.17 +/- 0.07-0.22 +/- 0.12 and 0.047 +/- 0.015-0.071 +/- 0.035 microg/g dry weight for Variegated Bolete; 0.28 +/- 0.11-0.79 +/- 0.40 and 0.17 +/- 0.07- 0.51 +/- 0.22 microg/g dw for European Cow Bolete, and 0.095 +/- 0.082-0.17 +/- 0.05 and 0.045 +/- 0.026- 0.070 +/- 0.026 microg/g dw for Slippery Jack. All three species of Suillus mushrooms bio-concentrated mercury (BCF > 1). European Cow Bolete bioconcentrated mercury relatively more efficiently when compared to two other species, and means of BCF value of this element in its caps ranged from 18 +/- 10 to 45 +/- 20, and in stipes from 9.4 +/- 7.5 to 29 +/- 11. A level of surface soil pollution with mercury was low and averaged from 0.017 +/- 0.003 do 0.029 +/- 0.020 microg/g dw.

Analytic representation of the backscatter correction factor at the exit of high energy photon beams

International Nuclear Information System (INIS)

Kappas, K.; Rosenwald, J.C.

1991-01-01

In high-energy X-ray beams, the dose calculated near the exit surface under electronic equilibrium conditions is generally over-estimated since it is derived from measurements performed in water with large thickness of backscattering material. The resulting error depends on a number of parameters such as beam energy, field dimension, thickness of overlying and underlying material. The authors have systematically measured for 4 different energies and for different para- meters and for different combinations of the above parameters, the reduction of dose due to backscatter. This correction is expressed as a multiplicative factor, called 'Backscatter Correction Factor' (BCF). This BCF is larger for lower energies, larger field sizes and larger depths. The BCF has been represented by an analytical expression which involves an exponential function of the backscattering thickness and linear relationships with depth field size and beam quality index. Using this expression, the BCF can be calculated within 0.5% for any conditions in the energy range investigated. (author). 14 refs.; 4 figs.; 3 tabs

Phytoextraction of potentially toxic elements by six tree species growing on hazardous mining sludge.

Science.gov (United States)

Mleczek, Mirosław; Goliński, Piotr; Krzesłowska, Magdalena; Gąsecka, Monika; Magdziak, Zuzanna; Rutkowski, Paweł; Budzyńska, Sylwia; Waliszewska, Bogusława; Kozubik, Tomisław; Karolewski, Zbigniew; Niedzielski, Przemysław

2017-10-01

The aim of the study was to compare the phytoextraction abilities of six tree species (Acer platanoides L., Acer pseudoplatanus L., Betula pendula Roth, Quercus robur L., Tilia cordata Miller, Ulmus laevis Pall.), cultivated on mining sludge contaminated with arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), thallium (Tl), and zinc (Zn). All six tree species were able to survive on such an unpromising substrate. However, A. platanoides and T. cordata seedlings grown on the polluted substrate showed significantly lower biomass than control plants (55.5 and 45.6%, respectively). As, Cd, Cu, Pb, and Tl predominantly accumulated in the roots of all the analyzed tree species with the following highest contents: 1616, 268, 2432, 547, and 856 mg kg -1 , respectively. Zn was predominantly localized in shoots with the highest content of 5801 and 5732 mg kg -1 for U. laevis and A. platanoides, respectively. A. platanoides was the most effective in Zn phytoextaction, with a bioconcentration factor (BCF) of 8.99 and a translocation factor (TF) of 1.5. Furthermore, with the exception of A. pseudoplatanus, the analyzed tree species showed a BCF > 1 for Tl, with the highest value for A. platanoides (1.41). However, the TF for this metal was lower than 1 in all the analyzed tree species. A. platanoides showed the highest BCF and a low TF and could, therefore, be a promising species for Tl phytostabilization. In the case of the other analyzed tree species, their potential for effective phytoextraction was markedly lower. Further studies on the use of A. platanoides in phytoremediation would be worth conducting.

Hyper accumulators of heavy metals of industrial areas of Islamabad and Rawalpindi

International Nuclear Information System (INIS)

Nazir, A.; Malik, R.N.; Ajaib, M.; Khan, N.; Siddiqui, M.F.

2011-01-01

Contamination of heavy metals is one of the major threats to water and soil as well as human health. Phytoremediation has been used to remediate metal-contaminated sites. This study evaluated the potential of 23 plant species growing on contaminated sites in Industrial areas of the Islamabad and Rawalpindi. Plant root, shoot and the soil samples were collected and analyzed for selected metal concentration values. To evaluate the potential of plant species for phyto remediation: Bioconcentration Factor (BCF), Biological Accumulation Coefficient (BAC) and Biological Transfer Coefficient (BCF) were calculated. The concentration of Pb in soils varied from 2-29 mg/kg, Zn from 28.82-172.56 mg/ kg, Cu from 8.88-306 mg/kg, respectively. The concentration of Pb in plant shoots varied from 1.0 to 39 mg/kg, Zn from 17.25 to 194.03 mg/kg, Cu from 0.65 to 171.83 mg/kg. The concentration of Pb in roots of plant varied 1-43 mg/kg, Zn from 3.34-116.16 mg/kg, Cu from 3.35- 416.89 mg/kg. Brachiaria raptans and Malvastrum coromandelianum were found most suitable for phyto stabilization of sites contaminated with Pb and Cu (BCF= 18 and 9.12). Considering the BAC values, 15 species for Pb, two species for Cu, five species for Zn possessed the characteristics of hyper accumulator, none of the plant species was found as hyper accumulator; however plants with high BCF (metal concentration ratio of plant root to soil) and low BTC (metal concentration ratio of plants shoots to roots) have the potential for phyto stabilization and phyto extraction. The results of this study can be used for management and decontamination of soils with heavy metals using plant species having phyto remediation potential/characteristics. (author)

Greenhouse cultivation mitigates metal-ingestion-associated health risks from vegetables in wastewater-irrigated agroecosystems

Energy Technology Data Exchange (ETDEWEB)

Cao, Chun [College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, Gansu (China); College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, Gansu (China); Chen, Xing-Peng; Ma, Zhen-Bang [College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, Gansu (China); Jia, Hui-Hui [State High-Tech Industrial Innovation Center, Shenzhen 518057, Guangdong (China); Wang, Jun-Jian, E-mail: junjian.wang@utoronto.ca [Department of Physical and Environmental Sciences, University of Toronto, Toronto M1C 1A4 (Canada)

2016-08-01

Wastewater irrigation can elevate metal concentrations in soils and crops and increase the metal-associated health risks via vegetable ingestion in arid and semiarid northwestern China. Here, we investigated the As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in four vegetable species from Dongdagou and Xidagou farmlands in Baiyin, Gansu, China. We evaluated the effects of irrigation type (Dongdagou: industrial wastewater; Xidagou: domestic wastewater) and cultivation mode (open field and greenhouse) on the vegetable metal concentration, metal partitioning, soil-to-plant bioconcentration factor (BCF), and the health risk index. All stream waters, soils, and vegetables were found most severely polluted by As and Cd, with higher severity in the industrial-wastewater-irrigated Dongdagou than the domestic-wastewater-irrigated Xidagou. All vegetables had higher or, at least, comparable metal mass allocated in the shoot than in the root. Greenhouse cultivation could reduce metal-ingestion-associated health risks from edible vegetable biomass by decreasing the soil to plant bioaccumulation (BCF) and the metal concentration. This effect was always significant for all vegetables within Xidagou, and for carrot within Dongdagou. This mitigation effect of greenhouse cultivation could be attributed to the metal sorption by a higher level of soil organic matter and faster growth rate over metal uptake rate in greenhouses compared to open fields. Such mitigation effect was, however, insignificant for leafy vegetables within Dongdagou, when much more severely polluted water for irrigation was applied in greenhouses compared to open fields within Dongdagou. The present study highlights greenhouse cultivation as a potential mitigating approach to providing less-polluted vegetables for residents in the severely polluted area in addition to the source pollution control. - Highlights: • Vegetable farmlands in Baiyin, Gansu, China were severely polluted by As and Cd. • Greenhouses had

Greenhouse cultivation mitigates metal-ingestion-associated health risks from vegetables in wastewater-irrigated agroecosystems

International Nuclear Information System (INIS)

Cao, Chun; Chen, Xing-Peng; Ma, Zhen-Bang; Jia, Hui-Hui; Wang, Jun-Jian

2016-01-01

Wastewater irrigation can elevate metal concentrations in soils and crops and increase the metal-associated health risks via vegetable ingestion in arid and semiarid northwestern China. Here, we investigated the As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in four vegetable species from Dongdagou and Xidagou farmlands in Baiyin, Gansu, China. We evaluated the effects of irrigation type (Dongdagou: industrial wastewater; Xidagou: domestic wastewater) and cultivation mode (open field and greenhouse) on the vegetable metal concentration, metal partitioning, soil-to-plant bioconcentration factor (BCF), and the health risk index. All stream waters, soils, and vegetables were found most severely polluted by As and Cd, with higher severity in the industrial-wastewater-irrigated Dongdagou than the domestic-wastewater-irrigated Xidagou. All vegetables had higher or, at least, comparable metal mass allocated in the shoot than in the root. Greenhouse cultivation could reduce metal-ingestion-associated health risks from edible vegetable biomass by decreasing the soil to plant bioaccumulation (BCF) and the metal concentration. This effect was always significant for all vegetables within Xidagou, and for carrot within Dongdagou. This mitigation effect of greenhouse cultivation could be attributed to the metal sorption by a higher level of soil organic matter and faster growth rate over metal uptake rate in greenhouses compared to open fields. Such mitigation effect was, however, insignificant for leafy vegetables within Dongdagou, when much more severely polluted water for irrigation was applied in greenhouses compared to open fields within Dongdagou. The present study highlights greenhouse cultivation as a potential mitigating approach to providing less-polluted vegetables for residents in the severely polluted area in addition to the source pollution control. - Highlights: • Vegetable farmlands in Baiyin, Gansu, China were severely polluted by As and Cd. • Greenhouses had

Trace elements in fruiting bodies of ectomycorrhizal fungi growing in Scots pine (Pinus sylvestris L.) stands in Poland

International Nuclear Information System (INIS)

Rudawska, Maria; Leski, Tomasz

2005-01-01

The trace metal contents in fruiting bodies of ectomycorrhizal (ECM) fungi, symbiotic partners of Scots pine, were studied on three sites situated in west-central Poland. Elements were determined by atomic absorption spectrometry in 123 samples of 16 species. The study explored the differences in metal accumulation in relation to site, fungal species, age and part of the fruiting body and results were related to metal content in soil and plant material (roots and needles). Soil analysis revealed that results were obtained under environmental conditions not subject to strong anthropogenic pressure. Median metal concentrations did not differ disparately between sites, although the concentrations of each of the tested metals in the individual species varied to a large extent. Extremely high levels of Al with a large bioconcentration factor (BCF) were found in sporocarps of Thelephora terrestris. The spread between the highest and the lowest concentration (max/min) was very wide in Al, Cd and Pb and these elements may be considered to be absorbed preferentially by fruiting bodies of some species whereas Fe, Mn and Zn, with relatively low values of max/min, are normally absorbed by the majority of fungi. There was no clear relationship between caps and stipes in metal content. However, a tendency to higher metal concentration in the caps was observed. The metal content in young and older fruiting bodies of five different fungi was species dependent. In order to estimate the degree of accumulation of each element by plant and mushrooms, bioconcentration factors (BCFs) were calculated. In plant material (roots and needles), highest values of BCFs were noted for essential metals, like Zn and Mn. Lead showed a definite exclusion pattern (BCF below 1). In fruiting bodies of tested fungi, especially in Amanita muscaria, cadmium was the most intensively accumulated metal. Lead was excluded by plants but was accumulated or excluded by fungi depending on the species. The

Phytoextraction with Salix viminalis in a moderately to strongly contaminated area.

Science.gov (United States)

Tőzsér, Dávid; Harangi, Sándor; Baranyai, Edina; Lakatos, Gyula; Fülöp, Zoltán; Tóthmérész, Béla; Simon, Edina

2018-02-01

We tested the suitability of Salix viminalis for phytoextraction with the analysis of selected elements in soil, root, and leaf, and by visual tree condition assessment in an area with varying levels of contamination. Bioconcentration factor (BCF) and translocation factor (TF) were used to assess the phytoextraction potential of willows. The middle part of the study area was strongly contaminated, while the northern and southern parts were moderately contaminated. We found increasing element concentrations toward deeper layers. Mean concentrations of elements in roots were similar among the three parts, while in leaves the highest concentrations were found in the strongly contaminated part of the study area. Tree condition scores were the lowest in the strongly contaminated part of the study area, which was caused by Al, Ca, K, Mg, Ni, Sr, and Zn concentration. These elements induced leaf disease and leaf feeders. The highest BCF values were found for Cu, Fe, Mn, and Zn in root, and for Cd and Zn in leaves, indicating that S. viminalis had high accumulation potential of these elements. Furthermore, TF values were high for Cd, Mn, Sr, and Zn. Our results also demonstrated that soil element composition has major influence on the condition of S. viminalis individuals. Furthermore, visual condition assessment was found to be a useful tool to assess the phytoextraction potential of trees.

Microbial Assisted Phyto remediation Of Palm Oil Mill Final Discharge (POMFD) Wastewater

International Nuclear Information System (INIS)

Mohd Faizal Hamzah; Norjan Yusof; Hasimah Alimon

2016-01-01

This study assesses microbial assisted phyto remediation of palm oil mill final discharge (POMFD) wastewater using three local macrophyte species: Leersia oryzoides, Pistia stratiotes and Ludwigia peploides. It was found respectively that BOD 5 , COD, NH 3 -N removal efficiencies of 84.7 %, 22.3 %, and 73.5 % were achieved for P. stratiotes; 88.1 %, 18 % and 69.2 % for L. peploides; and 86.1 %, 11.7 % and 69.3 % for L. oryzoides. The level of C, H and N in the tissue were influenced by macrophyte species and organs (p < 0.05). The bioconcentration factors (BCF) of various metals such as Mg, Ca, K, Na, Fe and Zn of the three macrophyte were 10 -1 to 10 0 with Fe being highly accumulated in roots of all the macrophyte (BCF=10 2 ). The translocation factors (TF) of most metals from root to shoot tissues were in a range of 10 -3 to 10 0 . In comparison with other metals, K was capable to be efficiently translocated from root to shoots in all the macrophyte species (TF=10 0 ). In this study, Bacillus megaterium, Pseudomonas spp. and Bacillus cereus that are usually involved in denitrification were identified in P. stratiotes, L. pepoides and L. oryzoides roots respectively. This confirms the macrophyte-microorganism interaction in remediation of POMFD wastewater. (author)

Fruit tree model for uptake of organic compounds from soil

DEFF Research Database (Denmark)

Trapp, Stefan; Rasmussen, D.; Samsoe-Petersen, L.

2003-01-01

-state, and an example calculation is given. The Fruit Tree Model is compared to the empirical equation of Travis and Arms (T&A), and to results from fruits, collected in contaminated areas. For polar compounds, both T&A and the Fruit Tree Model predict bioconcentration factors fruit to soil (BCF, wet weight based......) of > 1. No empirical data are available to support this prediction. For very lipophilic compounds (log K-OW > 5), T&A overestimates the uptake. The conclusion from the Fruit Tree Model is that the transfer of lipophilic compounds into fruits is not relevant. This was also found by an empirical study...... with PCDD/F. According to the Fruit Tree Model, polar chemicals are transferred efficiently into fruits, but empirical data to verify these predictions are lacking....

Marisa cornuarietis (Gastropoda, prosobranchia): a potential TBT bioindicator for freshwater environments.

Science.gov (United States)

Schulte-Oehlmann, U; Bettin, C; Fioroni, P; Oehlmann, J; Stroben, E

1995-12-01

: The ramshorn snail Marisa cornuarietis (L., 1767) exhibits imposex (occurrence of male parts in addition to the female genital duct) under the influence of TBT (tributyltin) in laboratory experiments and accumulates this biocide in a time-and concentration-dependent manner. A comparison of BCF (bioconcentration factors) demonstrates that this limnic species accumulates more TBT than marine species. Evidence is given that TBT causes hormonal disorders which are responsible for imposex development. The testosterone/oestradiol quotient reflects the imposex development which can be described by a classification scheme differentiating four stages in Marisa cornuarietis. In the background of the constantly increasing organotin concentration in the limnic environment Marisa cornuarietis could be a well-suited bioindicator for TBT pollution. No other limnic species with a lower threshold concentration for measurable TBT effects is reported within the literature.

Translocation of metal ions from soil to tobacco roots and their concentration in the plant parts.

Science.gov (United States)

da Silva, Cleber Pinto; de Almeida, Thiago E; Zittel, Rosimara; de Oliveira Stremel, Tatiana R; Domingues, Cinthia E; Kordiak, Januário; de Campos, Sandro Xavier

2016-12-01

This paper presents a study on the translocation factors (TFs) and bioconcentration factors (BCFs) of copper (Cu), manganese (Mn), zinc (Zn), cobalt (Co), chromium (Cr), cadmium (Cd), lead (Pb), iron (Fe), nickel (Ni), and arsenic (As) ions in roots, stems, and leaves of tobacco. The results revealed that during the tobacco growth, the roots are able to increase the sensitiveness of the physiological control, reducing the translocation of the metals Ni (0.38) and Pb (0.48) to the leaves. Cd and Zn presented factors TF and BCF >1 in the three tissues under analysis, which indicates the high potential for transportation and accumulation of these metals in all plant tissues. The TF values for Cr (0.65) and As (0.63) revealed low translocation of these ions to the aerial parts, indicating low mobility of ions from the roots. Therefore, tobacco can be considered an efficient accumulator of Ni, Cr, As and Pb in roots and Cd and Zn in all plant parts.

Uptake of polybrominated diphenyl ethers by carrot and lettuce crops grown in compost-amended soils.

Science.gov (United States)

Bizkarguenaga, E; Iparraguirre, A; Oliva, E; Quintana, J B; Rodil, R; Fernández, L A; Zuloaga, O; Prieto, A

2016-02-01

The uptake of polybrominated diphenyl ethers (PBDEs) by carrot and lettuce was investigated. Degradation of PBDEs in soil in the absence of the plants was discarded. Different carrot (Nantesa and Chantenay) and lettuce (Batavia Golden Spring and Summer Queen) varieties were grown in fortified or contaminated compost-amended soil mixtures under greenhouse conditions. After plant harvesting, roots (core and peel) and leaves were analyzed separately for carrot, while for lettuce, leaves and hearts were analyzed together. The corresponding bioconcentration factors (BCFs) were calculated. In carrots, a concentration gradient of 2,2',3,4,4',5'-hexabromodiphenyl ether (BDE-138) became evident that decreased from the root peel via root core to the leaves. For decabromodiphenyl ether (BDE-209) at the low concentration level (7 and 20 ng g(-1)), the leaves incorporated the highest concentration of the target substance. For lettuce, a decrease in the BCF value (from 0.24 to 0.02) was observed the higher the octanol-water partition coefficient, except in the case of BDE-183 (BCF = 0.51) and BDE-209 (BCF values from 0.41 to 0.74). Significant influence of the soils and crop varieties on the uptake could not be supported. Metabolic debromination, hydroxylation or methylation of the target PBDEs in the soil-plant system was not observed.

Total and bioavailable arsenic concentration in arid soils and its uptake by native plants from the pre-Andean zones in Chile.

Science.gov (United States)

Díaz, O; Tapia, Y; Pastene, R; Montes, S; Núñez, N; Vélez, D; Montoro, R

2011-06-01

Arsenic is the most important contaminant of the environment in northern Chile. Soil samples and plant organs from three native plant species, Pluchea absinthioides, Atriplex atacamensis and Lupinus microcarpus, were collected from arid zones in order to determine the total and bioavailable arsenic concentrations in soils and to assess the bioconcentration factor (BCF) and transport index (Ti) of arsenic in the plants. Total arsenic concentrations in soils (pH 8.3-8.5) where A. atacamensis and P. absinthioides were collected, reached levels considered to be contaminated (54.3 ± 15.4 and 52.9 ± 9.9 mg kg⁻¹, respectively), and these values were approximately ten times higher than in soils (pH 7.6) where L. microcarpus was collected. Bioavailable arsenic ranged from 0.18 to 0.42% of total arsenic concentration. In the three plant species, arsenic concentration in leaves were significantly (p ≤ 0.05) higher than in roots. L. microcarpus showed the highest arsenic concentration in its leaves (9.7 ± 1.6 mg kg⁻¹) and higher values of BCF (1.8) and Ti (6.1), indicating that this species has a greater capacity to accumulate and translocate the metalloid to the leaf than do the other species.

Estimation of Uptake of Humic Substances from Different Sources by Escherichia coli Cells under Optimum and Salt Stress Conditions by Use of Tritium-Labeled Humic Materials▿

Science.gov (United States)

Kulikova, Natalia A.; Perminova, Irina V.; Badun, Gennady A.; Chernysheva, Maria G.; Koroleva, Olga V.; Tsvetkova, Eugenia A.

2010-01-01

The primary goal of this paper is to demonstrate potential strengths of the use of tritium-labeled humic substances (HS) to quantify their interaction with living cells under various conditions. A novel approach was taken to study the interaction between a model microorganism and the labeled humic material. The bacterium Escherichia coli was used as a model microorganism. Salt stress was used to study interactions of HS with living cells under nonoptimum conditions. Six tritium-labeled samples of HS originating from coal, peat, and soil were examined. To quantify their interaction with E. coli cells, bioconcentration factors (BCF) were calculated and the amount of HS that penetrated into the cell interior was determined, and the liquid scintillation counting technique was used as well. The BCF values under optimum conditions varied from 0.9 to 13.1 liters kg−1 of cell biomass, whereas under salt stress conditions the range of corresponding values increased substantially and accounted for 0.2 to 130 liters kg−1. The measured amounts of HS that penetrated into the cells were 23 to 167 mg and 25 to 465 mg HS per kg of cell biomass under optimum and salt stress conditions, respectively. This finding indicated increased penetration of HS into E. coli cells under salt stress. PMID:20639375

Incorporation of inorganic mercury (Hg2+) in pelagic food webs of ultraoligotrophic and oligotrophic lakes: The role of different plankton size fractions and species assemblages

International Nuclear Information System (INIS)

Soto Cárdenas, Carolina; Diéguez, Maria C.; Ribeiro Guevara, Sergio; Marvin-DiPasquale, Mark; Queimaliños, Claudia P.

2014-01-01

In lake food webs, pelagic basal organisms such as bacteria and phytoplankton incorporate mercury (Hg 2+ ) from the dissolved phase and pass the adsorbed and internalized Hg to higher trophic levels. This experimental investigation addresses the incorporation of dissolved Hg 2+ by four plankton fractions (picoplankton: 0.2–2.7 μm; pico + nanoplankton: 0.2–20 μm; microplankton: 20–50 μm; and mesoplankton: 50–200 μm) obtained from four Andean Patagonian lakes, using the radioisotope 197 Hg 2+ . Species composition and abundance were determined in each plankton fraction. In addition, morphometric parameters such as surface and biovolume were calculated using standard geometric models. The incorporation of Hg 2+ in each plankton fraction was analyzed through three concentration factors: BCF (bioconcentration factor) as a function of cell or individual abundance, SCF (surface concentration factor) and VCF (volume concentration factor) as functions of individual exposed surface and biovolume, respectively. Overall, this investigation showed that through adsorption and internalization, pico + nanoplankton play a central role leading the incorporation of Hg 2+ in pelagic food webs of Andean lakes. Larger planktonic organisms included in the micro- and mesoplankton fractions incorporate Hg 2+ by surface adsorption, although at a lesser extent. Mixotrophic bacterivorous organisms dominate the different plankton fractions of the lakes connecting trophic levels through microbial loops (e.g., bacteria–nanoflagellates–crustaceans; bacteria–ciliates–crustaceans; endosymbiotic algae–ciliates). These bacterivorous organisms, which incorporate Hg from the dissolved phase and through their prey, appear to explain the high incorporation of Hg 2+ observed in all the plankton fractions. - Highlights: • Hg 2+ incorporation in lake plankton fractions was studied using the isotope 197 Hg 2+ . • Hg 2+ incorporation was assessed using three different

Incorporation of inorganic mercury (Hg{sup 2+}) in pelagic food webs of ultraoligotrophic and oligotrophic lakes: The role of different plankton size fractions and species assemblages

Energy Technology Data Exchange (ETDEWEB)

Soto Cárdenas, Carolina, E-mail: sotocardenascaro@gmail.com [Laboratorio de Fotobiología, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, 8400 San Carlos de Bariloche, Río Negro (Argentina); Diéguez, Maria C. [Laboratorio de Fotobiología, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, 8400 San Carlos de Bariloche, Río Negro (Argentina); Ribeiro Guevara, Sergio [Laboratorio de Análisis por Activación Neutrónica, CAB, CNEA, Av. Bustillo Km 9.5, 8400, San Carlos de Bariloche, Río Negro (Argentina); Marvin-DiPasquale, Mark [United States Geological Survey, 345 Middlefield Rd./MS 480, Menlo Park, CA 94025 (United States); Queimaliños, Claudia P. [Laboratorio de Fotobiología, Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, 8400 San Carlos de Bariloche, Río Negro (Argentina)

2014-10-01

In lake food webs, pelagic basal organisms such as bacteria and phytoplankton incorporate mercury (Hg{sup 2+}) from the dissolved phase and pass the adsorbed and internalized Hg to higher trophic levels. This experimental investigation addresses the incorporation of dissolved Hg{sup 2+} by four plankton fractions (picoplankton: 0.2–2.7 μm; pico + nanoplankton: 0.2–20 μm; microplankton: 20–50 μm; and mesoplankton: 50–200 μm) obtained from four Andean Patagonian lakes, using the radioisotope {sup 197}Hg{sup 2+}. Species composition and abundance were determined in each plankton fraction. In addition, morphometric parameters such as surface and biovolume were calculated using standard geometric models. The incorporation of Hg{sup 2+} in each plankton fraction was analyzed through three concentration factors: BCF (bioconcentration factor) as a function of cell or individual abundance, SCF (surface concentration factor) and VCF (volume concentration factor) as functions of individual exposed surface and biovolume, respectively. Overall, this investigation showed that through adsorption and internalization, pico + nanoplankton play a central role leading the incorporation of Hg{sup 2+} in pelagic food webs of Andean lakes. Larger planktonic organisms included in the micro- and mesoplankton fractions incorporate Hg{sup 2+} by surface adsorption, although at a lesser extent. Mixotrophic bacterivorous organisms dominate the different plankton fractions of the lakes connecting trophic levels through microbial loops (e.g., bacteria–nanoflagellates–crustaceans; bacteria–ciliates–crustaceans; endosymbiotic algae–ciliates). These bacterivorous organisms, which incorporate Hg from the dissolved phase and through their prey, appear to explain the high incorporation of Hg{sup 2+} observed in all the plankton fractions. - Highlights: • Hg{sup 2+} incorporation in lake plankton fractions was studied using the isotope {sup 197}Hg{sup 2+}. • Hg{sup 2

Bioaccumulation Behavior of Pharmaceuticals and Personal Care Products in Adult Zebrafish (Danio rerio): Influence of Physical-Chemical Properties and Biotransformation.

Science.gov (United States)

Chen, Fangfang; Gong, Zhiyuan; Kelly, Barry C

2017-10-03

The factors influencing bioaccumulation of pharmaceuticals and personal care products (PPCPs) in aquatic organisms are not well understood. The present study involved a comprehensive laboratory investigation to assess the bioaccumulation behavior of several PPCPs in adult zebrafish (Danio rerio). The studied PPCPs included several ionogenic organic compounds (IOCs) such as weak acids and weak bases. Experiments involved two exposure groups (high and low) and a control group, with a 6 day aqueous exposure, followed by a 7 day depuration phase under flow-through conditions. Uptake rate constants (k u ) ranged between 0.19 and 8610 L·kg -1 ·d -1 , while depuration rate constants (k d ) ranged between 0.14 and 5.14 d -1 in different fish tissues. Steady-state bioconcentration factor (BCF ss ) values varied widely among the studied PPCPs, ranging from 0.09 to 6,460. In many cases, BCF ss values of individual PPCPs differed substantially among different fish tissues. Positive linear relationships were observed between log BCF ss values and physical-chemical properties such as octanol-water distribution coefficients (log D ow ), membrane-water distribution coefficients (log D mw ), albumin-water distribution coefficients (log D BSAw ), and muscle protein-water distribution coefficients (log D mpw ), indicating the importance of lipid-, phospholipid-, and protein-water partitioning. The results also showed that for many PPCPs, the estimated whole-body metabolism rate constant (k m ) values were comparable to the observed depuration rate (k d ), indicating that metabolism plays a major role in the overall elimination of these compounds in zebrafish. An exception was sertraline, which exhibited a k d value (0.4-0.5 d -1 ) that was much higher than the estimated whole-body k m (0.03 d -1 ). Overall, the results help to better understand the influence of physical-chemical properties and biotransformation on bioaccumulation behavior of these contaminants of concern in aquatic

A feasibility study of perennial/annual plant species to restore soils contaminated with heavy metals

Science.gov (United States)

Zacarías, Montserrat; Beltrán, Margarita; Gilberto Torres, Luis; González, Abelardo

A feasibility study was carried out to evaluate the application of perennial/annual plant species in a phytoextraction process of a previously washed industrial urban soil contaminated by nickel, arsenic and cupper. The plant species selected for this study were Ipomea (Ipomea variada); grass (Poa pratensis); grass mixture (Festuca rubra, Cynodon dactylon, Lolium multiforum, Pennisetum sp.); Monks Cress (Tropaeolum majus); ficus (Ficus benajamina) and fern (Pteris cretica). Soil was characterized and it presented the following heavy metals concentrations (dry weight): 80 mg of Ni/kg, 456-656 mg of As/kg and 1684-3166 mg of Cu/kg. Germination and survival in contaminated soil tests were conducted, from these, P. pratensis was discarded and the rest of plant species tested were used for the phytoextraction selection test. After 4 months of growth, biomass production was determined, and content of Ni, As and Cu was analyzed in plant’s tissue. Metal biological absorption coefficient (BAC), bio-concentration factor (BCF) and translocation factor (TF), were calculated. Regarding to biomass generation it was observed, in every case, an inhibition of the plant growth compared with blanks sown in a non contaminated soil; inhibition ranged from 22.5% for the Monk cress to 98% for Ipomea. Even though the later presented high BAC, BCF and TF, its growth was severely inhibited, and therefore, due its low biomass generation, it is not recommended for phytoextraction under conditions for this study. Heavy metals concentrations in plant’s tissue (dry weight) were as high as 866 mg Cu/kg and 602 mg As/kg for grass mixture; and 825 mg As/kg was observed for Monks cress. Grass mixture and monks cress had high BAC, BCF and TF, also they had high metal concentrations in its plants tissues and the lowest growth inhibition rates; hence the application in phytoextraction processes of these plants is advisable.

Uptake and depuration of pharmaceuticals in aquatic invertebrates

International Nuclear Information System (INIS)

Meredith-Williams, Melanie; Carter, Laura J.; Fussell, Richard; Raffaelli, David; Ashauer, Roman; Boxall, Alistair B.A.

2012-01-01

The uptake and depuration of a range of pharmaceuticals in the freshwater shrimp (Gammarus pulex) and the water boatman (Notonecta glauca) was studied. For one compound, studies were also done using the freshwater snail Planobarius corneus. In G. pulex, bioconcentration factors (BCFs) ranged from 4.6 to 185,900 and increased in the order moclobemide < 5-fluoruracil < carbamazepine < diazepam < carvedilol < fluoxetine. In N. glauca BCFs ranged from 0.1 to 1.6 and increased in the order 5-fluorouracil < carbamazepine < moclobemide < diazepam < fluoxetine < carvedilol. For P. corneus, the BCF for carvedilol was 57.3. The differences in degree of uptake across the three organisms may be due to differences in mode of respiration, behaviour and the pH of the test system. BCFs of the pharmaceuticals for each organism were correlated to the pH-corrected liposome–water partition coefficient of the pharmaceuticals. - Highlights: ► One of the first studies exploring the uptake of pharmaceuticals into aquatic invertebrates. ► Data presented on uptake, depuration rates and bioconcentration for a range of pharmaceuticals. ► Uptake is correlated with the pH-corrected liposome–water partition coefficient. ► Findings can be used to better predict impacts of pharmaceuticals on the aquatic environment. - The factors affecting the degree of uptake of pharmaceuticals into aquatic invertebrates were studied. The results indicate that species traits such as respiration and behaviour of the organisms and pH-corrected liposome–water partition coefficients are important factors in determining pharmaceutical uptake.

Evaluation of phytoextracting cadmium and lead by sunflower, ricinus, alfalfa and mustard in hydroponic culture.

Science.gov (United States)

Zhi-xin, Niu; Sun, Li-na; Sun, Tie-heng; Li, Yu-shuang; Wang, Hong

2007-01-01

Soil contaminated with heavy metals cadmium (Cd) and lead (Pb) is hard to be remediated. Phytoremediation may be a feasible method to remove toxic metals from soil, but there are few suitable plants which can hyperaccumulate metals. In this study, Cd and Pb accumulation by four plants including sunflower (Helianthus annuus L.), mustard (Brassica juncea L.), alfalfa (Medicago sativa L.), ricinus (Ricinus communis L.) in hydroponic cultures was compared. Results showed that these plants could phytoextract heavy metals, the ability of accumulation differed with species, concentrations and categories of heavy metals. Values of BCF (bioconcentration factor) and TF (translocation factor) indicated that four species had dissimilar abilities of phytoextraction and transportation of heavy metals. Changes on the biomass of plants, pH and Eh at different treatments revealed that these four plants had distinct responses to Cd and Pb in cultures. Measurements should be taken to improve the phytoremediation of sites contaminated with heavy metals, such as pH and Eh regulations, and so forth.

Effect of pH on the toxicity and bioconcentration of sulfadiazine on Daphnia magna

DEFF Research Database (Denmark)

Anskjær, Gitte Gotholdt; Rendal, Cecilie; Kusk, Kresten Ole

2013-01-01

The antimicrobial sulfonamide sulfadiazine has in the last decades been detected in environmental water bodies, both surface and ground water. Since pH in the environment may vary considerably, this study examined the toxicity of the amphoter sulfadiazine towards Daphnia magna at pH levels of 6.......0, 7.5 and 8.5, thus taking the impact of speciation into consideration, contrary to earlier eco-toxicity studies conducted at standard conditions. Toxicity tests were performed using the standard ISO 6341 test procedure modified to accommodate the three pH levels and the toxicity was expressed as EC50....... After 48h the EC50 was determined to be 27.2, 188 and 310mgL−1 at pH 6.0, 7.5 and 8.5, respectively, thus demonstrating a significant effect of pH on the toxicity of sulfadiazine. Furthermore, the bioconcentration factor (dry weight) was determined to be 50 and 36 at pH 6.0 and 8.5, respectively...

Bioconcentration and acute toxicity of polycyclic musks in two benthic organisms (Chironomus riparius and Lumbriculus variegatus)

NARCIS (Netherlands)

Artola-Garicano, E.; Sinnige, T.L.; Holsteijn, I. van; Vaes, W.H.J.; Hermens, J.L.M.

2003-01-01

In the current study, the bioconcentration behavior and acute toxicity of two polycyclic musks, Tonalide® 7-acetyl-1,1,3,4,4,6,-hexamethyl-1,2,3,4,-tetrahydronaphthalene (AHTN) and Galaxolide® 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexa-methyl-cyclopenta[γ]-2- benzopyran (HHCB), were studied in two

Rare earth elements concentration in mushroom cultivation substrates affects the production process and fruit-bodies content of Pleurotus ostreatus and Cyclocybe cylindracea.

Science.gov (United States)

Koutrotsios, Georgios; Danezis, Georgios P; Georgiou, Constantinos A; Zervakis, Georgios I

2018-04-20

Concentrations of 16 rare earth elements (REEs) and two actinides were determined for the first time both in cultivated mushrooms and in their production substrates by inductively coupled plasma mass spectroscopy. Moreover, the effect of REEs on cultivation parameters and composition of the final product was assessed, together with their potential use for authentication purposes. The concentrations of REEs varied greatly among seven cultivation substrates and correlated with measurements in Cyclocybe cylindracea mushrooms; no such correlation was established in Pleurotus ostreatus. Reduction of hemicellulose, cellulose, and lignin in substrates during P. ostreatus cultivation was positively correlated with REE concentrations, which also affected the production performance depending on the species examined. In all cases, a negative correlation was established between bioconcentration factors (BCF) in mushrooms and REE content in substrates, while the effect of substrate composition on BCF values varied according to the element studied. The estimated daily intake values of REEs through mushroom consumption was at much lower levels than those reported as potentially harmful for human health. The content of REEs in cultivation substrates and in mushrooms revealed that the bioaccumulation of elements differed in each fungus. The nature/origin of substrates seemed to affect the concentration of REEs in mushrooms to a considerable extent. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Bioconcentration of the antidepressant fluoxetine and its effects on the physiological and biochemical status in Daphnia magna.

Science.gov (United States)

Ding, Jiannan; Zou, Hua; Liu, Qingqing; Zhang, Shanshan; Mamitiana Razanajatovo, Roger

2017-08-01

The aim of this study was to evaluate the bioconcentration potential of fluoxetine and its biological effects in Daphnia magna. After 48h of waterborne exposure, the bioconcentration of fluoxetine in D. magna was determined to be 460.61 and 174.41Lkg -1 for nominal exposure concentrations of 0.5 and 5µgL -1 , respectively. Moreover, various biological endpoints, including physiological responses (filtration and ingestion rates), enzymatic biomarkers related to neurotoxicity [acetylcholinesterase (AChE)] and antioxidant defense [superoxide dismutase (SOD)], and an oxidative stress damage marker [malondialdehyde (MDA)], were assessed. Fluoxetine exposure increased the filtration rate of daphnia, while the ingestion rate was not obviously modified. AChE activity was significantly inhibited, highlighting the neurotoxicity of fluoxetine on D. magna. However, with some alterations in the SOD activity and MDA content, no obvious oxidative damage was observed in D. magna exposed to fluoxetine at the tested concentrations. These results indicate that fluoxetine can be accumulated and consequently induce physiological and biochemical perturbations in D. magna. Copyright © 2017. Published by Elsevier Inc.

Accumulation and effects of copper on aquatic macrophytes Potamogeton pectinatus L.: Potential application to environmental monitoring and phytoremediation.

Science.gov (United States)

Costa, Marcela Brandão; Tavares, Francesca Valêncio; Martinez, Claudia Bueno; Colares, Ioni Gonçalves; Martins, Camila de Martinez Gaspar

2018-07-15

This study investigated the ability of Potamogeton pectinatus L. to accumulate copper and its effects on plants. In accumulation tests, macrophytes were exposed (96 h) to different copper concentrations (0-1000 µM) and the metal was measured in media and plant tissues (roots, stems and leaves) to determine the bioconcentration factor (BCF). Plants accumulated high concentrations of copper in a dose-dependent manner and roots was the main organ for copper accumulation. However, the more copper increased in water, the more BCF values decreased. It may be due to either saturation of copper uptake or down-regulation of metal uptake by plants. In the physiological and morphological analyses, plants were kept (96 h) in Hoagland nutrient solution without copper, in full Hoagland solution (0.5 µM Cu) and in Hoagland medium with copper from 1 to 100 µM. The absence and the presence of copper above to 1 µM inhibited photosynthesis. Chlorophylls and carotenoid levels also decreased with the excess of copper, a fact that may have affected the photosystem II-dependent of chlorophyll and caused photosynthesis suppression. Only macrophytes at 10 µM Cu showed decrease in length and number of leaves on the 10th day of the test, when they died. Chlorosis and necrosis were observed in control groups and groups with extra copper, but not in Hoalgand group. Overall, the macrophyte P. pectinatus can be considered a suitable plant for monitoring environments contaminated by copper, based on results of copper accumulation in the plant, decrease in pigment concentration and presence of chlorosis and necrosis. However, values of BCF based on fresh water tissues was not proper to indicate the use of P. pectinatus for cleaning environments contaminated by copper. Copyright © 2018 Elsevier Inc. All rights reserved.

Chemical analysis of fish bile extracts for monitoring endocrine disrupting chemical exposure in water: Bisphenol A, alkylphenols, and norethindrone.

Science.gov (United States)

Wu, Minghong; Pan, Chenyuan; Yang, Ming; Xu, Bentuo; Lei, Xiangjie; Ma, Jing; Cai, Ling; Chen, Jingsi

2016-01-01

The present study determined concentrations of estrogenic bisphenol A (BPA), nonylphenol, octylphenol (4-tert-octylphenol), butylphenol (4-tert-butylphenol), and progestogenic norethindrone by liquid chromatography-tandem mass spectrometry in bile extracts from field fish from the Xin'an River and market fish in Shanghai, China. Compared with the field fish, endocrine disrupting chemical (EDC) concentrations in market fish bile were at relatively high levels with high detectable rates. The average concentrations of BPA, nonylphenol, 4-tert-octylphenol, 4-tert-butylphenol, and norethindrone in field fish bile were 30.1 µg/L, 203 µg/L, 4.69 µg/L, 7.84 µg/L, and 0.514 µg/L, respectively; in market fish bile they were 240 µg/L, 528 µg/L, 76.5 µg/L, 12.8 µg/L, and 5.26 µg/L, respectively; and in the surface water of Xin'an River they were 38.8 ng/L, 7.91 ng/L, 1.98 ng/L, 2.66 ng/L, and 0.116 ng/L, respectively. The average of total estrogenic activity of river water was 3.32 ng/L estradiol equivalents. High bioconcentration factors (BCFs) were discovered for all 5 EDCs (≧998-fold) in field fish bile. Furthermore, the authors analyzed the BCF value of BPA in fish bile after 30-d exposure to environmentally relevant concentrations of BPA in the laboratory, and the analysis revealed that BCF in fish bile (BCF(Fish bile)) changed in an inverse concentration-dependent manner based on the log10-transformed BPA concentration in water. Strikingly, the data from the field study were well fitted within this trend. The data together suggested that analysis of fish bile extracts could be an efficient method for assessing waterborne EDCs exposure for aquatic biota. © 2015 SETAC.

Human health risk assessment: heavy metal contamination of vegetables in Bahawalpur, Pakistan

Directory of Open Access Journals (Sweden)

Hafiza Hira Iqbal

2016-01-01

Full Text Available Dietary exposure of toxic metals is a vital concern for human health through vegetable consumption, especially in developing countries. Aim of the current study was to determine the health risk related to vegetables contamination of heavy metals by irrigated with sewage and turbine water. Irrigation water sources, soils and vegetables were analyzed for selected metals viz: Pb, Cd, Cr and Ni. Heavy metals in water samples were within the permissible limits except Cd in sewage water. The concentration of heavy metals in soil and vegetables irrigated with turbine water were lower than the safe limits. In case of vegetables irrigated with sewage water, Cd was higher in soil while Pb, Cd and Cr were higher in most of the vegetables. Daily intake of metals, health risk index and Bio-concentration factor was also determined. Health risk index values for Cd, Pb and Ni were exceeded the permissible limits (European Union, 2002. Bio-concentration factor (BCF found to be maximum (16.4 mg/kg in Coriandrum sativum cultivated with sewage water. Raphanus caudatus, Coriandrum sativum, Daucus carota, Allium sativum and Solanum tuberosum showed Health Risk Index of Cd > 1 in adults and children. Allium sativum also showed HRI of Pb > 1 in children. We conclude that the quality of vegetables irrigated with sewage water is poor and not fit for human health, evident from the high concentration of Pb, Cd and Cr. Urgent measures are required to prevent consumption and production vegetables irrigated with of sewage water in the study area.

Heavy Metal Residues in Soil and Accumulation in Maize at Long-Term Wastewater Irrigation Area in Tongliao, China

Directory of Open Access Journals (Sweden)

Yintao Lu

2015-01-01

Full Text Available Soil and plant samples were collected from Tongliao, China, during the maize growth cycle between May and October 2010. Heavy metals, such as Cr, Pb, Ni, and Zn, were analyzed. The concentrations of Cr, Pb, Ni, and Zn in the wastewater-irrigated area were higher than those in the topsoil from the groundwater-irrigated area. The concentrations of metals in the maize increased as follows: Pb < Ni < Zn < Cr. In addition, Cr, Pb, and Ni mainly accumulated in the maize roots, and Zn mainly accumulated in the maize fruit. The results of translocation factors (TF and bioconcentration factors (BCF of maize for heavy metals revealed that maize is an excluder plant and a potential accumulator plant and can serve as an ideal slope remediation plant. In addition, the increasing heavy metal contents in soils that have been polluted by wastewater irrigation must result in the accumulation of Cr, Pb, Ni, and Zn in maize. Thus, the pollution level can be decreased by harvesting and disposing of and recovering the plant material.

Acute toxicity of dichloroacetonitrile (DCAN), a typical nitrogenous disinfection by-product (N-DBP), on zebrafish (Danio rerio).

Science.gov (United States)

Lin, Tao; Zhou, Dongju; Dong, Jian; Jiang, Fuchun; Chen, Wei

2016-11-01

Dichloroacetonitrile (DCAN) is a typical nitrogenous disinfection by-product (N-DBP) and its toxicity on aquatic animals is investigated for the first time. The present study was designed to investigate the potential adverse effects of DCAN on zebrafish. DCAN could induce developmental toxicity to zebrafish embryos. A significant decrease in hatchability and an increase in malformation and mortality occurred when DCAN concentration was above 100µg/L. Heart function alteration and neuronal function disturbance occurred at concentration higher than 500 and 100µg/L, respectively. Further, DCAN was easily accumulated in adult zebrafish. The rank order of declining bioconcentration factor (BCF) was liver (1240-1670)> gill (1210-1430)> muscle (644-877). DCAN caused acute metabolism damage to adult zebrafish especially at 8 days exposure, at which time the "Integrated Biomarker Response" (IBR) index value reached 798 at 1mg/L DCAN dose. Acute DNA damage was induced to adult zebrafish by DCAN even at 10µg/L dose. Copyright © 2016 Elsevier Inc. All rights reserved.

The Effect of Trichoderma on Heavy Metal Mobility and Uptake by Miscanthus giganteus, Salix sp., Phalaris arundinacea, and Panicum virgatum

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Malgorzata J. Kacprzak

2014-01-01

Full Text Available The effect of land application of biomaterials based on two strains of Trichoderma fungus on phytoremediation processes was studied. Six metals (Cd, Cr, Cu, Pb, Zn, and Ni were analysed in soil and soil leachate as well as in plant tissues. The translocation index (Ti and metal bioconcentration factors (BCF calculated for the inoculated plants were increased compared to the noninoculated control, except for Pb and Salix sp. Simultaneously, the mobilisation of metals in soil solution as an effect of biomaterials was noted. The highest values of Ti—339% (for Cr, 190% (for Ni, and 110% (for Cu—were achieved for the combination Miscanteus giganteus and Trichoderma MSO1. The results indicated that the application of fungus has positive effects on increasing the biomass, soil parameters (C, N, and P, and solubility of heavy metals in soil and therefore in enhancing phytoextraction for Miscanthus giganteus L., Panicum virgatum L., Phalaris arundinacea L., and Salix sp.

Accumulation and distribution of polycyclic aromatic hydrocarbons in rice (Oryza sativa)

International Nuclear Information System (INIS)

Tao, S.; Jiao, X.C.; Chen, S.H.; Liu, W.X.; Coveney, R.M.; Zhu, L.Z.; Luo, Y.M.

2006-01-01

Various tissues of rice plants were sampled from a PAH contaminated site in Tianjin, China at different growth stages of the ripening period and analyzed for PAHs. PAHs were much higher in roots than in the exposed tissues. Grains and internodes accumulated much smaller amounts of PAHs than leaves, hulls or ear axes. No specific gradient trends along roots, stem, ear axes, and grains were observed, suggesting that systematic translocation among them is unlikely. Over the ripening period, PAH concentrations were increased in rice roots and decreased in most above-ground tissues. Significant correlations between PAH and lipid contents can only be observed during full mature stage. The spectra of individual PAH compounds in rice organs including roots were similar to those in air, rather than those in soil. There was also a significant correlation between bioconcentration factor (BCF, plant over air) and octanol/air partitioning coefficient (K oa ). - PAHs in various tissues of rice plants from various growth stages were investigated

Effect of Transpiration on Plant Accumulation and Translocation of PPCP/EDCs

Science.gov (United States)

Dodgen, Laurel K; Ueda, Aiko; Wu, Xiaoqin; Parker, David R; Gan, Jay

2015-01-01

The reuse of treated wastewater for agricultural irrigation in arid and hot climates where plant transpiration is high may affect plant accumulation of pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs). In this study, carrot, lettuce, and tomato plants were grown in solution containing 16 PPCP/EDCs in either a cool-humid or a warm-dry environment. Leaf bioconcentration factors (BCF) were positively correlated with transpiration for chemical groups of different ionized states (p < 0.05). However, root BCFs were correlated with transpiration only for neutral PPCP/EDCs (p < 0.05). Neutral and cationic PPCP/EDCs showed similar accumulation, while anionic PPCP/EDCs had significantly higher accumulation in roots and significantly lower accumulation in leaves (p < 0.05). Results show that plant transpiration may play a significant role in the uptake and translocation of PPCP/EDCs, which may have a pronounced effect in arid and hot climates where irrigation with treated wastewater is common. PMID:25594843

Modelling oral up-take of hydrophobic and super-hydrophobic chemicals in fish.

Science.gov (United States)

Larisch, Wolfgang; Goss, Kai-Uwe

2018-01-24

We have extended a recently published toxicokinetic model for fish (TK-fish) towards the oral up-take of contaminants. Validation with hydrophobic chemicals revealed that diffusive transport through aqueous boundary layers in the gastro-intestinal tract and in the blood is the limiting process. This process can only be modelled correctly if facilitated transport by albumin or bile micelles through these boundary layers is accounted for. In a case study we have investigated the up-take of a super hydrophobic chemical, Dechlorane Plus. Our results suggest that there is no indication of a hydrophobicity or size cut-off in the bioconcentration of this chemical. Based on an extremely high, but mechanistically sound facilitation factor we received model results in good agreement with experimental values from the literature. The results also indicate that established experimental procedures for BCF determination cannot cover the very slow up-take and clearance kinetics that are to be expected for such a chemical.

Studies onthe behaviour of the insecticide 14C-Pirimiphos-Methyl in aquatic species: tilapia nilotica and potamogeton crispus plant

International Nuclear Information System (INIS)

Afifi, L.M.; Kamel, H.A.; Aly, M.A.S.

2003-01-01

The bioaccumulation and depletion of 1 4C-labelled pirimiphos-methyl (O-2- diethyl amino-6-methyl pyrimidine-4-gamma l O,O-dimethyl phosphorothioa) were monitored for 6 days following a single application at 7.5 ppm to 2 aquatic species: Bolti fish (Tilapia nilotica) and a rapid growing plant (Potamogeton crispus). The bioconcentration factor (BCF) for fish was relatively low with a maximum reached at 24 hours 122 and 55 in the absence and presence of the weed respectively. Depuration of the insecticide and/or its metabolites in clear water was readily fast. Feeding the treated dried fish to rat, the substance residues were found to be bioavailable where, 75.7% of the given amount was excreted in the urine and 15.3% in the feces. TLC analysis of the urine revealed the presence of 4 metabolites: Desethyl pirimiphos-methyl, 2-diethyl amino-4-hydroxy-6-methylpyrimidine, 2-ethyl amino-4-hydroxy-6-methyl-pyrimidine and 2-amino -4-hydroxy-6- methyl- pyrimidine

Kinetics of polychlorinated biphenyl partitioning to marine Chrysophyte Isochrysis galbana

International Nuclear Information System (INIS)

Ko, Fung-Chi; Baker, Joel E.; Tew, Kwee S.

2012-01-01

This study focused on the uptake kinetics of polychlorinated biphenyl (PCB) congeners by the Chrysophyte, Isochrysis galbana. A gas-purging experimental system was used to maintain constant dissolved PCB concentrations. Three phases of absorption were observed: first, a rapid absorption phase within the first 15 min, second, a first order process reaching the maximum concentration within 48 h of exposure, and third, a plateau phase as yet to be determined with very slight increases in concentration. In this study, the percentage of the maximum concentration reached within the first phase varied from 10% to 67%, depending on the size of the PCB (as determined by molecular weight and total surface area), whereas the uptake rate (k u ) during the second phase was more comparable across different PCBs. In addition, for the first phase, the bioconcentration factor (BCF) of PCBs deviated from its expected relationship with hydrophobicity, as determined by K ow , and was instead related to the molecular structure of the compound.

TREATMENT OF HEAVY METALS FROM WATER BY ELECTRO-PHYTOREMEDIATION TECHNIQUE

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Harikumar Puthenveedu Sadasivan Pillai

2017-09-01

Full Text Available The performance of electrically stimulated phytoremediation in the removal of lead, cadmium and copper was assessed in this study. A combination of phyto and electro remediation was attempted in this study for the remediation of the metals from water. Three tanks were setup with different operating conditions for this experiment: control A (only phytoremediation system, control B (only electro remediation and treatment (combination of phyto and electro remediation. The electrically enhanced phytoremediation system and electro remediation system were operated 2h/day at voltages of 4V for 25 days continuously. In this experiment, the Eichhornia crassipes, an able phyto-remediator exhibited efficient and fast removal of heavy metals from synthetic solution in electro assisted phytoremediation system. The electrically enhanced phytoremediation using aluminum sheet electrodes showed better and effective removal of Cd, Pb and Cu than aluminum rod electrodes. A more favorable and moderate increase of pH was noticed in electrically stimulated phytoremediation system. Eichhornia crassipes has tremendous potential to reduce maximum amount of cadmium (within 15 days, lead (within 15 days and copper (within 10 days under electrically stimulated condition. Under electrified condition, maximum amount of Cd and Cu was accumulated in the aerial parts of Eichhornia crassipes but maximum concentration of Pb was attained by roots. This indicates the high heavy metal accumulation capacity of Eichhornia crassipes under electrified conditions. The results showed that 4V voltage is probably suitable to stimulate the Eichhornia crassipes to synthesize more chlorophyll and voltage can improve growth and ability to resist adverse circumstances by promoting chlorophyll synthesis. Eichhornia crassipes stimulated by an electric field has grown better and assimilated more metal. Bioconcentration factor (BCF an index of hyperaccumulation, indicates that electrically

Using DTPA-extractable soil fraction to assess the bioconcentration factor of plants in phytoremediation of urban soils

Science.gov (United States)

Rodríguez-Bocanegra, Javier; Roca, Núria; Tume, Pedro; Bech, Jaume

2017-04-01

Urban soils may be highly contaminated with potentially toxic metals, as a result of intensive anthropogenic activities. Developing cities are increasing the number of lands where is practiced the urban agriculture. In this way, it is necessary to assess the part of heavy metals that is transferred to plants in order to a) know the potential health risk that represent soils and b) know the relation soil-plant to assess the ability of these plants to remove heavy metals from soil. Nowadays, to assess the bioconcentration factor (BF) of plants in phytoremediation, the pseudototal o total concentration has been used by many authors. Two different urban soils with similar pH and carbonates content but with different pollution degree were phytoremediated with different plant species. Urban soil from one Barcelona district (Spain), the most contaminated soil, showed an extractability of Cu, Pb and Zn of 9.6, 6.7 and 5.8% of the total fraction respectively. The soil from Talcahuano city (Chile), with contents of heavy metals slightly above the background upper limit, present values of 15.5, 13.5 and 12% of the total fraction of studied heavy metals. Furthermore, a peri-urban analysed soil from Azul (Argentina) also showed an elevated extractability with values of 24, 13.5 and 14% of the Cu, Pb and Zn contents respectively. These soils presented more extractability than other disturbed soils, like for example, soils from mine areas. The urban soils present more developed soil with an interaction between solution and solid phase in polluted systems. The most important soil surface functional groups include the basal plane of phyllosilicates and metal hydroxyls at edge sites of clay minerals, iron oxyhydroxides, manganese oxyhydroxides and organic matter. The interaction between solution and solid phase in polluted urban systems tends to form labile associations and pollutants are more readily mobilized because their bonds with soil particles are weaker. Clay and organic

A comparison of BCF-12 organic scintillators and Al2O3:C crystals for real-time medical dosimetry

DEFF Research Database (Denmark)

Beierholm, Anders Ravnsborg; Andersen, Claus Erik; Lindvold, Lars

2008-01-01

Radioluminescence (RL) from aluminium oxide (Al2O3:C) crystals and organic scintillators such as the blue-emitting BCF-12 can be used for precise real-time dose rate measurements during radiation therapy of cancer patients. Attaching the dosimeters to thin light-guiding fiber cables enables in vivo...... use. The light signal is detected by a photomultiplier tube (PNIT). Unfortunately Cerenkov light and fluorescence are also generated in the fiber cable itself during irradiation, and this so-called stem effect can be significant compared with the dosimeter signal. In the case of Al2O3:C, this problem...... can be circumvented for pulsed beams due to the long life-time of the main luminescence center. In contrast, chromatic removal seems to be the most effective method for organic scintillators, but is found to yield some experimental complexities. In this paper, we report on dose rate measurements using...

Metal uptake by homegrown vegetables – The relative importance in human health risk assessments at contaminated sites

International Nuclear Information System (INIS)

Augustsson, Anna L.M.; Uddh-Söderberg, Terese E.; Hogmalm, K. Johan; Filipsson, Monika E.M.

2015-01-01

Risk assessments of contaminated land often involve the use of generic bioconcentration factors (BCFs), which express contaminant concentrations in edible plant parts as a function of the concentration in soil, in order to assess the risks associated with consumption of homegrown vegetables. This study aimed to quantify variability in BCFs and evaluate the implications of this variability for human exposure assessments, focusing on cadmium (Cd) and lead (Pb) in lettuce and potatoes sampled around 22 contaminated glassworks sites. In addition, risks associated with measured Cd and Pb concentrations in soil and vegetable samples were characterized and a probabilistic exposure assessment was conducted to estimate the likelihood of local residents exceeding tolerable daily intakes. The results show that concentrations in vegetables were only moderately elevated despite high concentrations in soil, and most samples complied with applicable foodstuff legislation. Still, the daily intake of Cd (but not Pb) was assessed to exceed toxicological thresholds for about a fifth of the study population. Bioconcentration factors were found to vary more than indicated by previous studies, but decreasing BCFs with increasing metal concentrations in the soil can explain why the calculated exposure is only moderately affected by the choice of BCF value when generic soil guideline values are exceeded and the risk may be unacceptable. - Highlights: • Uptake of Cd and Pb by lettuce and potatoes increased with soil contamination. • Consumption of homegrown vegetables may lead to a daily Cd intake above TDIs. • The variability in the calculated BCFs is high when compared to previous studies. • Exposure assessments are most sensitive to the choice of BCFs at low contamination

Metal uptake by homegrown vegetables – The relative importance in human health risk assessments at contaminated sites

Energy Technology Data Exchange (ETDEWEB)

Augustsson, Anna L.M., E-mail: anna.augustsson@lnu.se [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden); Uddh-Söderberg, Terese E. [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden); Hogmalm, K. Johan [Department of Earth Sciences, University of Gothenburg, Gothenburg (Sweden); Filipsson, Monika E.M. [Department of Biology and Environmental Science, Linnaeus University, SE-391 82 Kalmar (Sweden)

2015-04-15

Risk assessments of contaminated land often involve the use of generic bioconcentration factors (BCFs), which express contaminant concentrations in edible plant parts as a function of the concentration in soil, in order to assess the risks associated with consumption of homegrown vegetables. This study aimed to quantify variability in BCFs and evaluate the implications of this variability for human exposure assessments, focusing on cadmium (Cd) and lead (Pb) in lettuce and potatoes sampled around 22 contaminated glassworks sites. In addition, risks associated with measured Cd and Pb concentrations in soil and vegetable samples were characterized and a probabilistic exposure assessment was conducted to estimate the likelihood of local residents exceeding tolerable daily intakes. The results show that concentrations in vegetables were only moderately elevated despite high concentrations in soil, and most samples complied with applicable foodstuff legislation. Still, the daily intake of Cd (but not Pb) was assessed to exceed toxicological thresholds for about a fifth of the study population. Bioconcentration factors were found to vary more than indicated by previous studies, but decreasing BCFs with increasing metal concentrations in the soil can explain why the calculated exposure is only moderately affected by the choice of BCF value when generic soil guideline values are exceeded and the risk may be unacceptable. - Highlights: • Uptake of Cd and Pb by lettuce and potatoes increased with soil contamination. • Consumption of homegrown vegetables may lead to a daily Cd intake above TDIs. • The variability in the calculated BCFs is high when compared to previous studies. • Exposure assessments are most sensitive to the choice of BCFs at low contamination.

Distribution and bioconcentration of heavy metals in a tropical aquatic food web: A case study of a tropical estuarine lagoon in SE Mexico

International Nuclear Information System (INIS)

Mendoza-Carranza, Manuel; Sepúlveda-Lozada, Alejandra; Dias-Ferreira, Celia; Geissen, Violette

2016-01-01

Despite the increasing impact of heavy metal pollution in southern Mexico due to urban growth and agricultural and petroleum activities, few studies have focused on the behavior and relationships of these pollutants in the biotic and abiotic components of aquatic environments. Here, we studied the bioaccumulation of heavy metals (Cd, Cr, Ni, Pb, V, Zn) in suspended load, sediment, primary producers, mollusks, crustaceans, and fish, in a deltaic lagoon habitat in the Tabasco coast, with the aim to assess the potential ecological risk in that important wetland. Zn showed the highest concentrations, e.g., in suspended load (mean of 159.58 mg kg"−"1) and aquatic consumers (15.43–171.71 mg kg"−"1), particularly Brachyura larvae and ichthyoplankton (112.22–171.71 mg kg"−"1), followed by omnivore Callinectes sp. crabs (113.81–128.07 mg kg"−"1). The highest bioconcentration factors (BCF) of Zn were observed for planktivore and omnivore crustaceans (3.06–3.08). Zn showed a pattern of distribution in the food web through two pathways: the pelagic (where the higher concentrations were found), and the benthic (marsh plants, sediment, mollusk, fish). The other heavy metals had lower occurrences in the food web. Nevertheless, high concentrations of Ni and Cr were found in phytoplankton and sediment (37.62–119.97 mg kg"−"1), and V in epiphytes (68.64 mg kg"−"1). Ni, Cr, and Cd concentrations in sediments surpassed international and national threshold values, and Cd entailed a “considerable” potential risk. These heavy metals are most likely transferred into the food web up to fishes through the benthic pathway. Most of the collected fishes are residents in this type of habitat and have commercial importance. Our results show that the total potential ecological risk in the area can be considered as “moderate”. Nevertheless, heavy metal values were similar or surpassed the values from other highly industrialized tropical coastal regions

Heavy metal sensitivity and bioconcentration in oribatid mites (Acari, Oribatida)

Energy Technology Data Exchange (ETDEWEB)

Skubala, Piotr, E-mail: piotr.skubala@us.edu.pl [Department of Ecology, University of Silesia, Bankowa 9, 40-007 Katowice (Poland); Zaleski, Tomasz [Department of Soil Science and Soil Protection, Agricultural University in Krakow, Mickiewicza 21, 31-120 Cracow (Poland)

2012-01-01

In this study we aimed to identify different reactions of oribatid species to heavy metal pollution and to measure concentrations of cadmium, zinc and copper in oribatid species sampled along a gradient. Oribatid mites were sampled seasonally during two years in five meadows located at different distances from the zinc smelter in the Olkusz District, southern Poland. Oribatids were shown to withstand critical metal concentration and established comparatively abundant and diverse communities. The highest abundance and species richness of oribatids were recorded in soils with moderate concentrations of heavy metals. Four different responses of oribatid species to heavy metal pollution were recognized. Heavy metals (Zn, Pb, Cd, Ni) and various physical (bulk density, field capacity, total porosity) and chemical (K{sub av}, P{sub av}, N, C, pH) factors were recognized as the structuring forces that influence the distribution of oribatid species. Analysis by atomic absorption spectrophotometry revealed large differences in metal body burdens among species. None of the species can be categorized as accumulators or non-accumulators of the heavy metals - the pattern depends on the metal. The process of bioconcentration of the toxic metal (regulated) and essential elements (accumulated) was generally different in the five oribatid species studied. - Highlights: Black-Right-Pointing-Pointer Responses of oribatid mites to metal contamination along a gradient in meadow soils were studied. Black-Right-Pointing-Pointer Small concentrations of heavy metals positively influenced the abundance of oribatid mites. Black-Right-Pointing-Pointer Four different responses of oribatid species to heavy metal pollution were recognised. Black-Right-Pointing-Pointer Bioaccumulation of the toxic metal and essential elements proceeded differently in oribatid species. Black-Right-Pointing-Pointer Five studied oribatid species were deconcentrators of cadmium.

Monitoring and assessment of mercury pollution in the vicinity of a chloralkali plant. IV. Bioconcentration of mercury in in situ aquatic and terrestrial plants at Ganjam, India.

Science.gov (United States)

Lenka, M; Panda, K K; Panda, B B

1992-02-01

In situ aquatic and terrestrial plants including a few vegetable and crop plants growing in and around a chloralkali plant at Ganjam, India were analyzed for concentrations of root and shoot mercury. The aquatic plants found to bioconcentrate mercury to different degrees included Marsilea spp., Spirodela polyrhiza, Jussiea repens, Paspalum scrobiculatam, Pistia stratiotes, Eichhornia crassipes, Hygrophila schulli, Monochoria hastata and Bacopa monniera. Among wild terrestrial plants Chloris barbata, Cynodon dactylon, Cyperus rotundus and Croton bonplandianum were found growing on heavily contaminated soil containing mercury as high as 557 mg/kg. Analysis of mercury in root and shoot of these plants in relation to the mercury levels in soil indicated a significant correlation between soil and plant mercury with the exception of C. bonplandianum. Furthermore, the tolerance to mercury toxicity was highest with C. barbata followed by C. dactylon and C. rotundus, in that order. The rice plants analyzed from the surrounding agricultural fields did not show any significant levels of bioconcentrated mercury. Of the different vegetables grown in a contaminated kitchen garden with mercury level at 8.91 mg/kg, the two leafy vegetables, namely cabbage (Brassica oleracea) and amaranthus (Amaranthus oleraceous), were found to bioconcentrate mercury at statistically significant levels. The overall study indicates that the mercury pollution is very much localized to the specific sites in the vicinity of the chloralkali plant.

Environmental risk assessment of selected organic chemicals based on TOC test and QSAR estimation models.

Science.gov (United States)

Chi, Yulang; Zhang, Huanteng; Huang, Qiansheng; Lin, Yi; Ye, Guozhu; Zhu, Huimin; Dong, Sijun

2018-02-01

Environmental risks of organic chemicals have been greatly determined by their persistence, bioaccumulation, and toxicity (PBT) and physicochemical properties. Major regulations in different countries and regions identify chemicals according to their bioconcentration factor (BCF) and octanol-water partition coefficient (Kow), which frequently displays a substantial correlation with the sediment sorption coefficient (Koc). Half-life or degradability is crucial for the persistence evaluation of chemicals. Quantitative structure activity relationship (QSAR) estimation models are indispensable for predicting environmental fate and health effects in the absence of field- or laboratory-based data. In this study, 39 chemicals of high concern were chosen for half-life testing based on total organic carbon (TOC) degradation, and two widely accepted and highly used QSAR estimation models (i.e., EPI Suite and PBT Profiler) were adopted for environmental risk evaluation. The experimental results and estimated data, as well as the two model-based results were compared, based on the water solubility, Kow, Koc, BCF and half-life. Environmental risk assessment of the selected compounds was achieved by combining experimental data and estimation models. It was concluded that both EPI Suite and PBT Profiler were fairly accurate in measuring the physicochemical properties and degradation half-lives for water, soil, and sediment. However, the half-lives between the experimental and the estimated results were still not absolutely consistent. This suggests deficiencies of the prediction models in some ways, and the necessity to combine the experimental data and predicted results for the evaluation of environmental fate and risks of pollutants. Copyright © 2016. Published by Elsevier B.V.

Using ecosystem modelling techniques in exposure assessments of radionuclides - an overview

International Nuclear Information System (INIS)

Kumblad, L.

2005-01-01

The risk to humans from potential releases from nuclear facilities is evaluated in safety assessments. Essential components of these assessments are exposure models, which estimate the transport of radionuclides in the environment, the uptake in biota, and transfer to humans. Recently, there has been a growing concern for radiological protection of the whole environment, not only humans, and a first attempt has been to employ model approaches based on stylized environments and transfer functions to biota based exclusively on bioconcentration factors (BCF). They are generally of a non-mechanistic nature and involve no knowledge of the actual processes involved, which is a severe limitation when assessing real ecosystems. in this paper, the possibility of using an ecological modelling approach as a complement or an alternative to the use of BCF-based models is discussed. The paper gives an overview of ecological and ecosystem modelling and examples of studies where ecosystem models have been used in association to ecological risk assessment studies for other pollutants than radionuclides. It also discusses the potential to use this technique in exposure assessments of radionuclides with a few examples from the safety assessment work performed by the Swedish nuclear fuel and waste management company (SKB). Finally there is a comparison of the characteristics of ecosystem models and traditionally exposure models for radionuclides used to estimate the radionuclide exposure of biota. The evaluation of ecosystem models already applied in safety assessments has shown that the ecosystem approach is possible to use to assess exposure to biota, and that it can handle many of the modelling problems identified related to BCF-models. The findings in this paper suggest that both national and international assessment frameworks for protection of the environment from ionising radiation would benefit from striving to adopt methodologies based on ecologically sound principles and

Phytoremediation of heavy metal copper (Cu2+) by sunflower (Helianthus annuus l.)

Science.gov (United States)

Mahardika, G.; Rinanti, A.; Fachrul, M. F.

2018-01-01

A study in microcosmic condition has been carried out to determine the effectiveness of Helianthus annuus as a hyperaccumulator plant for heavy metal, Copper (Cu2+), that exposed in the soil. Artificial pollutants containing Copper (Cu2+) 0, 60, 120, 180 ppm are exposed to uncontaminated soil. The 12-weeks old H. annuus seedling were grown in Cu2+ contaminated soil, with variations of absorption time 3, 6, and 9 weeks. Analysis of Cu2+ concentration on soil and H. annuus (root, stem, leaf) was analised by Atomic Absorbtion Spectrometry (AAS). H. annuus are capable for Cu2+ removal, and the highest removal of Cu2+ is 85.56%, the highest metal accumulation/bioconcentration factor (BCF) is 0.99 occurred at roots with 9 weeks of exposure time and the highest translocation factor (TF) is 0.71. This highest removal is five times better than absorption by stems and leaves. The results concluded, the use of H. annuus for phytoextraction of heavy metals Cu2+ in contaminated soil can be an alternative to the absorption of heavy metal Cu2+ with low concentration metals which is generally very difficult to do in physical-chemical removal.

Accumulation and distribution of mercury in fruiting bodies by fungus Suillus luteus foraged in Poland, Belarus and Sweden.

Science.gov (United States)

Saba, Martyna; Falandysz, Jerzy; Nnorom, Innocent C

2016-02-01

Presented in this paper is result of the study of the bioconcentration potential of mercury (Hg) by Suillus luteus mushroom collected from regions within Central, Eastern, and Northern regions of Europe. As determined by cold-vapor atomic absorption spectroscopy, the Hg content varied from 0.13 ± 0.05 to 0.33 ± 0.13 mg kg(-1) dry matter for caps and from 0.038 ± 0.014 to 0.095 ± 0.038 mg kg(-1) dry matter in stems. The Hg content of the soil substratum (0-10 cm layer) underneath the fruiting bodies showed generally low Hg concentrations that varied widely ranging from 0.0030 to 0.15 mg kg(-1) dry matter with mean values varying from 0.0078 ± 0.0035 to 0.053 ± 0.025 mg kg(-1) dry matter, which is below typical content in the Earth crust. The caps were observed to be on the richer in Hg than the stems at ratio between 1.8 ± 0.4 and 5.3 ± 2.6. The S. luteus mushroom showed moderate ability to accumulate Hg with bioconcentration factor (BCF) values ranging from 3.6 ± 1.3 to 42 ± 18. The consumption of fresh S. luteus mushroom in quantities up to 300 g week(-1) (assuming no Hg ingestion from other foods) from background areas in the Central, Eastern, and Northern part of Europe will not result in the intake of Hg exceeds the provisional weekly tolerance limit (PTWI) of 0.004 mg kg(-1) body mass.

Tributyltin distribution and producing androgenic activity in water, sediment, and fish muscle.

Science.gov (United States)

Shue, Meei-Fang; Chen, Ting-Chien; Bellotindos, Luzvisminda M; Lu, Ming-Chun

2014-01-01

This study investigated the concentrations of Tributyltin (TBT) in water, sediment, and fish muscle samples taken from Kaohsiung Harbor and Kaoping River estuary, Taiwan. TBT concentrations in water and sediment samples ranged from less than 18.5 to 34.1 ng Sn L(-1) and from 2.44 to 29.7 ng Sn g(-1) weight per weight (w/w), respectively. Concentrations in the TBT-contaminated fish muscle samples ranged from 10.8 to 79.6 ng Sn g(-1) w/w. The TBT concentrations in fish muscle were higher than those in water and sediment samples. The fish muscle/water TBT bioconcentration factor (BCF) ranged from 590 to 3363 L kg(-1). Additionally, the water samples were assessed for androgenic activity with an MCF7-AR1 human breast cancer cell line. The androgenic activity ranged from 0.94 to 3.1 ng-dihydrotestosterone per litre water (ng-DHT L(-1)). Higher concentrations of TBT in water and sediment samples occurred in the dry season, but the androgenic activity had higher values in the rainy season.

Heavy metal contamination in soil, food crops and associated health risks for residents of Ropar wetland, Punjab, India and its environs.

Science.gov (United States)

Sharma, Sakshi; Nagpal, Avinash Kaur; Kaur, Inderpreet

2018-07-30

In the present study, an assessment of heavy metal content in soil and food crops (wheat, rice, maize grains and mustard seeds) and associated health risks was carried out for residents of Ropar wetland and its environs. All the soil samples had high cadmium and cobalt contents, whereas, all crop samples had high contents of cobalt and lead. Bioconcentration factor (BCF) analysis indicated that rice grains act as hyper-accumulators of chromium (BCF = 17.98) and copper (BCF = 10.91), whereas, maize grains act as hyper-accumulators of copper (BCF = 30.43). One-way ANOVA suggested that heavy metal content in food crops varied significantly at p ≤ 0.05 for different sites, indicating anthropogenic contribution of heavy metals in agricultural fields. Dietary intake of cobalt via all food crops posed higher non-cancer health risk to residents in comparison to other heavy metals. Chromium posed highest cancer risk through consumption of wheat grains, being staple diet in study area. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of artificial sweeteners on metal bioconcentration and toxicity on a green algae Scenedesmus obliquus.

Science.gov (United States)

Hu, Hongwei; Deng, Yuanyuan; Fan, Yunfei; Zhang, Pengfei; Sun, Hongwen; Gan, Zhiwei; Zhu, Hongkai; Yao, Yiming

2016-05-01

The ecotoxicity of heavy metals depends much on their speciation, which is influenced by other co-existing substances having chelating capacity. In the present study, the toxic effects of Cd(2+) and Cu(2+) on a green algae Scenedesmus obliquus were examined in the presence of two artificial sweeteners (ASs), acesulfame (ACE) and sucralose (SUC) by comparing the cell specific growth rate μ and pulse-amplitude-modulated (PAM) parameters (maximal photosystem II photochemical efficiency Fv/Fm, actual photochemical efficiency Yield, and non-photochemical quenching NPQ) of the algae over a 96-h period. Simultaneously, the bioconcentration of the metals by the algal cells in the presence of the ASs was measured. The presence of ACE enhanced the growth of S. obliquus and promoted the bioconcentration of Cd(2+) in S. obliquus, while the impacts of SUC were not significant. Meanwhile, EC50 values of Cd(2+) on the growth of S. obliquus increased from 0.42 mg/L to 0.54 mg/L and 0.48 mg/L with the addition of 1.0 mg/L ACE and SUC, respectively. As for Cu(2+), EC50 values increased from 0.13 mg/L to 0.17 mg/L and 0.15 mg/L with the addition of 1.0 mg/L ACE and SUC, respectively. In summary, the two ASs reduced the toxicity of the metals on the algae, with ACE showing greater effect than SUC. Although not as sensitive as the cell specific growth rate, PAM parameters could disclose the mechanisms involved in metal toxicity at subcellular levels. This study provides the first evidence for the possible impact of ASs on the ecotoxicity of heavy metals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Content and Bioaccumulation of Nine Mineral Elements in Ten Mushroom Species of the Genus Boletus

Directory of Open Access Journals (Sweden)

Xue-Mei Wang

2015-01-01

Full Text Available Concentrations and bioconcentration potential of nine elements (Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn in ten species of wild edible Boletus and the corresponding underlying soils were analyzed. The analyses were performed using inductively coupled plasma atomic emission spectrophotometer. Boletus showed relative abundant contents of P, K, Fe, Mg, Ca, and Na and less of Zn, Cu, and Mn. Caps compared to stalks were enriched in P, K, Cu, Mg, and Zn, while stalks were enriched in Mn. The elements such as P and K were accumulated (BCF>1, while Ca, Fe, Mg, Mn, and Na were excluded (BCF<1 in the fruiting bodies. The correlation analysis indicated high correlations between Cu, Mn, Ca, and Fe in the mushrooms as compared to the corresponding soils. Significant correlations were also obtained between Cu-P (r=0.775, Fe-P (r=0.728, and Zn-P (r=0.76 for caps and Cu-Mg (r=0.721, Fe-Mg (r=0.719, Zn-Mg (r=0.824, and Zn-P (r=0.818 for stalks. The results of this study imply that ability of fungi to accumulate elements from substrate could be influenced by mushroom species and underlying soil substrates.

Content and Bioaccumulation of Nine Mineral Elements in Ten Mushroom Species of the Genus Boletus.

Science.gov (United States)

Wang, Xue-Mei; Zhang, Ji; Li, Tao; Wang, Yuan-Zhong; Liu, Hong-Gao

2015-01-01

Concentrations and bioconcentration potential of nine elements (Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn) in ten species of wild edible Boletus and the corresponding underlying soils were analyzed. The analyses were performed using inductively coupled plasma atomic emission spectrophotometer. Boletus showed relative abundant contents of P, K, Fe, Mg, Ca, and Na and less of Zn, Cu, and Mn. Caps compared to stalks were enriched in P, K, Cu, Mg, and Zn, while stalks were enriched in Mn. The elements such as P and K were accumulated (BCF > 1), while Ca, Fe, Mg, Mn, and Na were excluded (BCF < 1) in the fruiting bodies. The correlation analysis indicated high correlations between Cu, Mn, Ca, and Fe in the mushrooms as compared to the corresponding soils. Significant correlations were also obtained between Cu-P (r = 0.775), Fe-P (r = 0.728), and Zn-P (r = 0.76) for caps and Cu-Mg (r = 0.721), Fe-Mg (r = 0.719), Zn-Mg (r = 0.824), and Zn-P (r = 0.818) for stalks. The results of this study imply that ability of fungi to accumulate elements from substrate could be influenced by mushroom species and underlying soil substrates.

Investigations performed on the compost worm Eisenia fetida and selected species of earthworms concerning the intake of HCB and pyrene with the goal of deriving a bioaccumulation test; Untersuchungen zur Aufnahme von HCB und Pyren durch den Kompostwurm Eisenia fetida und ausgewaehlte Regenwurmwildarten. Ableitung eines Bioakkumulationstests

Energy Technology Data Exchange (ETDEWEB)

Vespermann, A.; Riepert, F.; Pflugmacher, J. [Biologische Bundesanstalt fuer Land- und Forstwirtschaft, Inst. fuer Oekotoxikologie im Pflanzenschutz, Berlin (Germany)

2003-07-01

The man issues of the studies described were the validation of a test design for the assessment of the bioaccumulation potential of environmental pollutants and the applicability of Eisenia fetida as a model-organism and artificial soil (OECD) as a standard test substrate. The test organisms used were E. fetida of our own breeding stock and Allolobophora caliginosa, Allolobophora chlorotica, Allolobophora longa and Lumbricus rubellus sampled from a field site. Test soils used were the artificial soil (OECD) and a BBA field soil. Soils were each contaminated with 10 mg HCB and Pyrene per soil dry-weight. Within the test period of 4 weeks, samples were taken weekly for residue analysis in the worms and soils. Bioaccumulation factors (AF) calculated for E. fetida and the free-living species were in the range of 10-17 (HCB) and 0.9-1.7 (Pyrene) depending on the soil used. By re-calculation of the concentrations in soil to concentrations in soil water, the resulting bioconcentration factors are compared with published BCF values determined from QSAR's of other worm species and fresh water fish. It could be concluded that the existing earthworm tests (OECD 1984, ISO 1998) represent an appropriate design for testing the bioconcentration potential of chemicals in soil. (orig.) [German] Ziel der beschriebenen Untersuchungen war die praktische Ueberpruefung eines Methodenentwurfs zur Erfassung der Bioakkumulation von Umweltchemikalien mit Eisenia fetida, der Eignung von E. fetida als Modellorganismus und des OECD-Kunstbodens als Standardsubstrat. Als Testorganismen wurden aus eigener Zucht der Kompostwurm Eisenia fetida und nach Feldentnahme Allolobophora caliginosa, Allolobophora chlorotica, Allolobophora longa und Lumbricus rubellus eingesetzt. Testboeden waren der OECD-Kunstboden und ein Boden vom Versuchsfeld der BBA in Berlin-Dahlem. Beiden Boeden wurden die Testsubstanzen Hexachlorbenzol und Pyren in einer Konzentration von 10 mg/kg Bodentrockengewicht zugemischt

Determination and validation of soil thresholds for cadmium based on food quality standard and health risk assessment.

Science.gov (United States)

Ding, Changfeng; Ma, Yibing; Li, Xiaogang; Zhang, Taolin; Wang, Xingxiang

2018-04-01

Cadmium (Cd) is an environmental toxicant with high rates of soil-plant transfer. It is essential to establish an accurate soil threshold for the implementation of soil management practices. This study takes root vegetable as an example to derive soil thresholds for Cd based on the food quality standard as well as health risk assessment using species sensitivity distribution (SSD). A soil type-specific bioconcentration factor (BCF, ratio of Cd concentration in plant to that in soil) generated from soil with a proper Cd concentration gradient was calculated and applied in the derivation of soil thresholds instead of a generic BCF value to minimize the uncertainty. The sensitivity variations of twelve root vegetable cultivars for accumulating soil Cd and the empirical soil-plant transfer model were investigated and developed in greenhouse experiments. After normalization, the hazardous concentrations from the fifth percentile of the distribution based on added Cd (HC5 add ) were calculated from the SSD curves fitted by Burr Type III distribution. The derived soil thresholds were presented as continuous or scenario criteria depending on the combination of soil pH and organic carbon content. The soil thresholds based on food quality standard were on average 0.7-fold of those based on health risk assessment, and were further validated to be reliable using independent data from field survey and published articles. The results suggested that deriving soil thresholds for Cd using SSD method is robust and also applicable to other crops as well as other trace elements that have the potential to cause health risk issues. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of titanium dioxide nanoparticles on lead bioconcentration and toxicity on thyroid endocrine system and neuronal development in zebrafish larvae.

Science.gov (United States)

Miao, Wei; Zhu, Biran; Xiao, Xiaohong; Li, Ying; Dirbaba, Niguse Bekele; Zhou, Bingsheng; Wu, Hongjuan

2015-04-01

Nanoparticles (NPs) have attracted considerable attention because of their wide range of applications. Interactions between heavy metals (e.g., Pb) and NPs in aquatic environments may modify the bioavailability and toxicity of heavy metals. Therefore, this study investigated the influence of NPs (e.g., nano-TiO2) on the bioavailability and toxicity of Pb and its effects in the thyroid endocrine and nervous systems of zebrafish (Danio rerio) larvae. Zebrafish embryos (2-h post-fertilization) were exposed to five concentrations of Pb alone (0, 5, 10, 20, and 30μg/L) or in combination with nano-TiO2 (0.1mg/L) until 6 days post-fertilization. Results showed that the bioconcentration of Pb was significantly enhanced when combined with nano-TiO2 than when used alone. Zebrafish exposure to Pb alone at 30μg/L significantly decreased the thyroid hormone levels (T4 and T3), whereas nano-TiO2 treatment alone did not produce detectable changes. The levels of T4 and T3 were further decreased when Pb was combined with nano-TiO2 than when used alone. The transcription of the thyroid hormone-related factor tg gene was remarkably down-regulated by Pb treatment alone but up-regulated when Pb was combined with nano-TiO2. The significant up-regulation of tshβ gene and the down-regulation of TTR gene expression in the hypothalamic-pituitary-thyroid were observed in Pb with or without nano-TiO2 treatment groups. In addition, the transcription of genes involved in central nervous system (CNS) development (α-tubulin, mbp, gfap and shha) were significantly down-regulated by Pb and nano-TiO2 co-exposure as compared with Pb exposure alone. The locomotion activity analyzes confirmed that nano-TiO2 might enhance the toxicity of Pb to CNS development. These results suggest that nano-TiO2 increase bioconcentration of lead, which lead to the disruption of thyroid endocrine and neuronal system in zebrafish larvae. Copyright © 2015 Elsevier B.V. All rights reserved.

Accumulation of current-use and organochlorine pesticides in crab embryos from northern California, USA.

Science.gov (United States)

Smalling, Kelly L; Morgan, Steven; Kuivila, Kathryn K

2010-11-01

Invertebrates have long been used as resident sentinels for assessing ecosystem health and productivity. The shore crabs, Hemigrapsus oregonensis and Pachygrapsus crassipes, are abundant in estuaries and beaches throughout northern California, USA and have been used as indicators of habitat conditions in several salt marshes. The overall objectives of the present study were to conduct a lab-based study to test the accumulation of current-use pesticides, validate the analytical method and to analyze field-collected crabs for a suite of 74 current-use and legacy pesticides. A simple laboratory uptake study was designed to determine if embryos could bioconcentrate the herbicide molinate over a 7-d period. At the end of the experiment, embryos were removed from the crabs and analyzed by gas chromatography/mass spectrometry. Although relatively hydrophilic (log K(OW) of 2.9), molinate did accumulate with an estimated bioconcentration factor (log BCF) of approximately 2.5. Following method validation, embryos were collected from two different Northern California salt marshes and analyzed. In field-collected embryos 18 current-use and eight organochlorine pesticides were detected including synthetic pyrethroids and organophosphate insecticides, as well as DDT and its degradates. Lipid-normalized concentrations of the pesticides detected in the field-collected crab embryos ranged from 0.1 to 4 ppm. Pesticide concentrations and profiles in crab embryos were site specific and could be correlated to differences in land-use practices. These preliminary results indicate that embryos are an effective sink for organic contaminants in the environment and have the potential to be good indicators of ecosystem health, especially when contaminant body burden analyses are paired with reproductive impairment assays. © 2010 SETAC.

The environmental toxicology of rare earth elements (147Pm, 141Ce, 147Nd) and their safety evaluation in environment

International Nuclear Information System (INIS)

Chen Zuyi; Liu Yu; Cheng Wei; Zhang Ligan; Li Huixin; Wang Yuanxing

2001-01-01

The environmental behaviour, bioconcentration of rare earth elements and their effects on the animal gonadial hormone secretion were studied using the radioisotope tracer. The results were as follows: (1) The 147 Pm, 141 Ce and 147 Nd have strong adsorption in soil. They accumulated in soil easily and belonged to the matter which was difficult to move. When in water body, they concentrated in the bottom mud. (2) The authors tested bioconcentration factors (BCF) of 5 aquatics and absorption coefficients of 3 aquatic vegetables on 147 Pm, and their concentration in edible organ-stems. The materials for study showed apparent concentrating capabilities. (3) The distribution of 147 Pm, 141 Ce and 147 Nd residues were uneven in the animal's viscera and tissue. But, the higher residues were in bone, marrow, eye, brain, heart, adipose and testis, and their accumulation increased with dosage and time, which showed selective accumulation. There were much higher accumulation of RE in bone than in other viscera and tissues, and 141 Ce was highest in eye. (4) With the Nd or Ce of dose 200 mg/kg by once intraperitoneally, gonadial hormone (testosterone or progesterone) concentration in the serum decreased significantly compared with the control. This showed apparent inhibition on gonadial hormone secretion in mice; however with different dosages of Ce (200 and 800 mg/kg · d) in feed, the testosterone concentration of serum made no significant difference, but, the misshape rate of spermatozoon proved higher, and the misshape rate increased with feeding time and dosage. Rudimentary exploration on safety of agricultural use of Re for eco-environment are made, and some suggestions are proposed

Bio-concentration of Polycyclic Aromatic Hydrocarbons in the grey Mangrove (Avicennia marina along eastern coast of the Red Sea

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El-Amin Bashir M.

2017-12-01

Full Text Available There are numerous sources of chemical pollutants which can impact the mangrove ecosystem through adjacent waters, industrial and sewage discharges and air depositions. Polycyclic aromatic hydrocarbons (PAHs are semi volatile ubiquitous anthropogenic pollutants detected in all environmental compartments. In the monitoring framework for the mangrove ecosystem along the Red Sea coast of Saudi Arabia, nine mangrove stands were examined for the accumulation of PAHs. Polycyclic aromatic hydrocarbons were measured using Gas Chromatography-Mass Spectrometry (GC-MS. The mean values detected for total PAHs in sediments, roots and leaf were 2.98, 8.57 and 23.43 ng/g respectively. The trend of the total PAHs concentration in all sites showed the descending order: leaf > roots > sediments. Beside the sandy nature of the sediments, the presences of all stands in remote areas fare from the direct anthropogenic effects lead to these relative low values. PAH bio-concentration factors for leaf are two to three magnitudes higher than that in roots, suggesting atmosphere deposition /leaf uptake mechanism in addition to the sediment/root mechanism. The diagnostic ratios revealed that the sources of PAHs are mainly pyrogenic.

Cadmium tolerance and phytoremediation potential of acacia (Acacia nilotica L.) under salinity stress.

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Shabir, Rahat; Abbas, Ghulam; Saqib, Muhammad; Shahid, Muhammad; Shah, Ghulam Mustafa; Akram, Muhammad; Niazi, Nabeel Khan; Naeem, Muhammad Asif; Hussain, Munawar; Ashraf, Farah

2018-06-07

In this study, we explored the effect of salinity on cadmium (Cd) tolerance and phytoremediation potential of Acacia nilotica. Two-month-old uniform plants of A. nilotica were grown in pots contaminated with various levels of Cd (0, 5, 10, and 15 mg kg -1 ), NaCl (0%, 0.5%, 1.0% (hereafter referred as salinity), and all possible combinations of Cd + salinity for a period of six months. Results showed that shoot and root growth, biomass, tissue water content and chlorophyll (chl a, chl b, and total chl a+b) contents decreased more in response to salinity and combination of Cd + salinity compared to Cd alone. Shoot and root K concentrations significantly decreased with increasing soil Cd levels, whereas Na and Cl concentrations were not affected significantly. Shoot and root Cd concentrations, bioconcentration factor (BCF) and translocation factor (TF) increased with increasing soil Cd and Cd + salinity levels. At low level of salinity (0.5%), shoot and root Cd uptake enhanced, while it decreased at high level of salinity (1.0%). Due to Cd tolerance, high shoot biomass and shoot Cd uptake, this tree species has some potential for phytoremediation of Cd from the metal contaminated saline and nonsaline soils.

Thallium contamination in arable soils and vegetables around a steel plant-A newly-found significant source of Tl pollution in South China.

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Liu, Juan; Luo, Xuwen; Wang, Jin; Xiao, Tangfu; Chen, Diyun; Sheng, Guodong; Yin, Meiling; Lippold, Holger; Wang, Chunlin; Chen, Yongheng

2017-05-01

Thallium (Tl) is a highly toxic rare element. Severe Tl poisoning can cause neurological brain damage or even death. The present study was designed to investigate contents of Tl and other associated heavy metals in arable soils and twelve common vegetables cultivated around a steel plant in South China, a newly-found initiator of Tl pollution. Potential health risks of these metals to exposed population via consumption of vegetables were examined by calculating hazard quotients (HQ). The soils showed a significant contamination with Tl at a mean concentration of 1.34 mg/kg. The Tl levels in most vegetables (such as leaf lettuce, chard and pak choy) surpassed the maximum permissible level (0.5 mg/kg) according to the environmental quality standards for food in Germany. Vegetables like leaf lettuce, chard, pak choy, romaine lettuce and Indian beans all exhibited bioconcentration factors (BCF) and transfer factors (TF) for Tl higher than 1, indicating a hyperaccumulation of Tl in these plants. Although the elevated Tl levels in the vegetables at present will not immediately pose significant non-carcinogenic health risks to residents, it highlights the necessity of a permanent monitoring of Tl contamination in the steel-making areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cadmium phytoextraction from loam soil in tropical southern China by Sorghum bicolor.

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Wang, Xu; Chen, Can; Wang, Jianlong

2017-06-03

The cadmium (Cd) uptake characteristics by Sorghum bicolor cv. Nengsi 2# and Cowley from the acidic sandy loam soil (pH = 6.1) during the entire growth period (100 days) were investigated in pot outdoors in a tropical district of southern China, Hainan Island. The Cd-spiked levels in soil were set as 3 and 15 mg/kg. Correspondingly, the available Cd levels in soil extracted by Mehlich III solution were 2.71 and 9.41 mg/kg, respectively. Basically, two varieties in a full growth period (100 days) did not show a significant difference in their growth and Cd uptake. Under high Cd stress, the plant growth was inhibited and its biomass weight and height decreased by 38.7-51.5% and 27.6-28.5%, respectively. However, S. bicolor showed higher bioaccumulation capability of Cd from soil to plant [bioconcentration factor (BCF)>4], and higher transfer capability of Cd from roots to shoots [translocation factor (TF)>1] under high Cd stress; Cd contents in the roots, stems, and leaves of S. bicolor reached 43.79-46.07, 63.28-70.60, and 63.10-66.06 mg/kg, respectively. S. bicolor exhibited the potential phytoextraction capability for low or moderate Cd-contamination in acidic sandy loam soil.

Opportunities for Phytoremediation and Bioindication of Arsenic Contaminated Water Using a Submerged Aquatic Plant:Vallisneria natans (lour.) Hara.

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Chen, Guoliang; Liu, Xingmei; Brookes, Philip C; Xu, Jianming

2015-01-01

The identification of plants with high arsenic hyperaccumulating efficiency from water is required to ensure the successful application of phytoremediation technology. Five dominant submerged plant species (Vallisneria natans (Lour.) Hara., Potamageton crispus L., Myriophyllum spicatum L., Ceratophyllum demersum L. and Hydrilla verticillata (L.f.) Royle) in China were used to determine their potential to remove As from contaminated water. V. natans had the highest accumulation of As among them. The characteristics of As accumulation, transformation and the effect of phosphate on As accumulation in V. natans were then further studied. The growth of V. natans was not inhibited even when the As concentration reached 2.0 mg L(-1). After 21 d of As treatment, the bioconcentration factor (BCF) reached 1300. The As concentration in the environment and exposure time are major factors controlling the As concentration in V. natans. After being absorbed, As(V) is efficiently reduced to As(III) in plants. The synthesis of non-enzymic antioxidants may play an important role under As stress and increase As detoxication. In addition, As(V) uptake by V. natans was negatively correlated with phosphate (P) uptake when P was sufficiently supplied. As(V) is probably taken up via P transporters in V. natans.

Can Cd translocation in Oryza sativa L. be attenuated by arbuscular mycorrhizal fungi in the presence of EDTA?

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Huang, Xiaochen; An, Guangnan; Zhu, Shishu; Wang, Li; Ma, Fang

2018-04-01

Arbuscular mycorrhizal (AM) fungi play an important role in plant tolerance of heavy metal contamination. In this study, a pot experiment was conducted to illustrate the effects of the two AM fungi species Funneliformis mosseae (Fm) and Rhizophagus irregularis (Ri) on plant growth of Oryza sativa L. either with or without ethylenediamine tetraacetate (EDTA) addition and during exposure to five Cd concentrations (in the range of 0-5 mg kg -1 ). The results showed that Fm inoculation achieved greater mycorrhizal colonization and mycorrhizal dependency indexes than Ri inoculation. In addition, the effects of AM fungi on Cd biosorption and translocation in rice were also investigated in the presence of EDTA. Despite cooperative adsorption, the Freundlich isotherm could describe the biosorption effects of Cd on rice roots regardless of AM fungi inoculation or EDTA addition. Cd concentrations in mycorrhizal roots increased but decreased in mycorrhizal shoots in contrast to the control treatment. Although EDTA addition negatively inhibited the uptake of Cd to mycorrhizal shoots, lower translocation factor (TF) and bioconcentration factor (BCF) were still observed in treatments with EDTA compared to control treatment. Our findings suggest that Ri and Fm inoculation enhanced Cd immobilization in the roots, thus preventing Cd entry into the food chain during exposure to low and high Cd stress, respectively.

Impact of dissolved organic matter on bioavailability of chlorotoluron to wheat

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Song Ninghui [Department of Applied Chemistry, College of Sciences, Nanjing Agricultural University, Weigang No. 1, Building of Chemistry, Nanjing 210095 (China); Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095 (China); Zhang Shuang; Hong Min [Department of Applied Chemistry, College of Sciences, Nanjing Agricultural University, Weigang No. 1, Building of Chemistry, Nanjing 210095 (China); Yang Hong, E-mail: hongyang@njau.edu.c [Department of Applied Chemistry, College of Sciences, Nanjing Agricultural University, Weigang No. 1, Building of Chemistry, Nanjing 210095 (China); Key Laboratory of Monitoring and Management of Crop Diseases and Pest Insects, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095 (China)

2010-03-15

Chlorotoluron (Chl) is a phenylurea herbicide and is widely used for controlling weeds. While it has brought great benefits to crop production, it has also resulted in contamination to ecosystem. In this study, we investigated accumulation of chlorotoluron (Chl) and biological responses of wheat plants as affected by dissolved organic matter (DOM). Wheat seedlings grown under 10 mg kg{sup -1} Chl for 4 d showed a low level of chlorophyll accumulation and damage to plasma membrane. The growth was inhibited by exposure of chlorotoluron. Treatment with 50 mg DOC kg{sup -1} DOM derived either from sludge (DOM-SL) or straw (DOM-ST) attenuated the chlorotoluron toxicity to plants. Both DOMs decreased activities of catalase, peroxidase and superoxide dismutase in Chl-treated seedlings. However, an increased glutathione S-transferases activity was observed under the same condition. Wheat plants treated with Chl in the presence of DOM accumulated less Chl than those treated with Chl alone. Moreover, in the presence of DOM, bioconcentration factor (BCF) decreased whereas translocation factors increased. Analyses with FT-IR spectra confirmed the regulatory role of DOMs in reducing Chl accumulation in wheat. - Dissolved organic matter (DOM) as a soil amendment can reduce herbicide accumulation in crops.

Apple snails and their endosymbionts bioconcentrate heavy metals and uranium from contaminated drinking water.

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Vega, Israel A; Arribére, María A; Almonacid, Andrea V; Ribeiro Guevara, Sergio; Castro-Vazquez, Alfredo

2012-09-01

The differential ability of apple snail tissues, endosymbionts, and eggs to bioaccumulate several metals (Sb, As, Ba, Br, Zn, Cr, Fe, Hg, Se, and U) was investigated. Metal concentrations were determined by neutron activation analysis in several tissues, endosymbionts, and eggs from mature apple snails cultured in either drinking water or reconstituted water (prepared with American Society for Testing and Materials type I water). The highest bioconcentration factors (BCFs) in the midgut gland were found for Ba, Zn, Se, As, U, Br, and Hg (in decreasing order), while the highest in the kidney were for Ba, Br, and Hg. The foot showed the highest BCFs for Ba, Hg, Br, and Se (in decreasing order). Calcified tissues (uterus, shell) and eggs showed low BCFs, except for Ba. Both C corpuscles and gland tissue showed statistically higher BCFs than K corpuscles for Ba, Fe, U, Br, and Sb. The concentration of most of the studied elements was significantly lower in tissues and endosymbionts obtained from snails cultured in reconstituted water instead of drinking water. Snails cultured in reconstituted water and then exposed or not to Hg, As, and U (at the maximum contaminant level allowed by the US Environmental Protection Agency) also resulted in high levels accumulated in midgut gland, endosymbionts and kidney. Our findings suggest that the midgut gland (and the symbionts contained therein), the kidney, and the foot of Pomacea canaliculata may be useful bioindicators of Hg, As and U pollution in freshwater bodies and that the unrestricted use of ampullariid snails as human and animal food must be considered with caution.

Dissecting variation in biomass conversion factors across China's forests: implications for biomass and carbon accounting.

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Luo, Yunjian; Zhang, Xiaoquan; Wang, Xiaoke; Ren, Yin

2014-01-01

Biomass conversion factors (BCFs, defined as the ratios of tree components (i.e. stem, branch, foliage and root), as well as aboveground and whole biomass of trees to growing stock volume, Mg m-3) are considered as important parameters in large-scale forest biomass carbon estimation. To date, knowledge of possible sources of the variation in BCFs is still limited at large scales. Using our compiled forest biomass dataset of China, we presented forest type-specific values of BCFs, and examined the variation in BCFs in relation to forest type, stand development and environmental factors (climate and soil fertility). BCFs exhibited remarkable variation across forest types, and also were significantly related to stand development (especially growing stock volume). BCFs (except Stem BCF) had significant relationships with mean annual temperature (MAT) and mean annual precipitation (MAP) (Pforest carbon estimates, we should apply values of BCFs for a specified forest type, and also consider climatic and edaphic effects, especially climatic effect, in developing predictive models of BCFs (except Stem BCF).

Survey on composition and bioconcentration potential of 12 metallic elements in King Bolete (Boletus edulis) mushroom that emerged at 11 spatially distant sites.

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Falandysz, Jerzy; Frankowska, Aneta; Jarzynska, Grazyna; Dryzałowska, Anna; Kojta, Anna K; Zhang, Dan

2011-01-01

This paper provides data on baseline concentrations, interrelationships and bioconcentration potential of 12 metallic elements by King Bolete collected from 11 spatially distant sites across Poland. There are significant differences in concentrations of metals (Al, Ba, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Sr, Zn) and their bioconcentration potential in King Bolete Boletus edulis at 11 spatially distant sites surveyed across Poland. These have resulted from significant geographical differences in trace metal concentrations in a layer (0-10 cm) of organic and mineral soil underneath to fruiting bodies and possible local bioavailabilities of macro- (Ca, K, Mg, Na) and trace metals (Al, Ba, Cd, Cu, Fe, Mn, Sr, Zn) to King Bolete. The use of highly appreciated wild-grown edible King Bolete mushroom has established a baseline measure of regional minerals status, heavy metals pollution and assessment of intake rates for wild mushroom dish fanciers against which future changes can be compared. Data on Cd, Cu and Zn from this study and from literature search can be useful to set the maximum limit of these metals in King Bolete collected from uncontaminated (background) areas. In this report also reviewed are data on Al, Ba, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Sr and Zn accumulation in King Bolete.

Radiocesium bioaccumulation in freshwater plankton: Influences of cation concentrations (K+ and Na+) on direct uptake of 137Cs in Chlamydomonas, Scenedesmus and Daphnia. Food-chain transfer of 137Cs from Chlamydomonas to Daphnia at different K+ concentrations

International Nuclear Information System (INIS)

Hagstroem, J.

2002-01-01

The influences of cation concentrations (K + and Na + ) on radiocesium ( 137 Cs) bioaccumulation in two freshwater phytoplankton species (Scenedesmus quadricauda and Chlamydomonas noctigama) were systematically investigated in batch-cultures monitored during two weeks. Both species were cultured at 9 μE M -2 s -1 constant illumination at 20 deg. C. The exponential growth phase lasted for more than 100 hours (μ ≅ 0.02 h -1 for C. noctigama and 0.03 h -1 for S, quadricauda). Over cation concentration ranges encountered in natural fresh waters ([K + ] from 0.1 μM to 3 mM, [Na + ] from 20 μM to 3 mM), a more than three order of magnitude variation was found for both intake rate and observed bioconcentration factors (BCF) at apparent steady-state (from less than 10 3 to 10 6 L (kg C) -1 ). For both species, the major effector on BCF and uptake rate was external [K + ], which was inversely proportional to these parameters over wide ranges (1-1000 μM for S. quadricauda and 0.1 to 300 μM for C. noctigama). At concentrations above these ranges K + still reduced 137 Cs bio-uptake, but less effectively. A minor influence of external [Na + ] on 137 Cs bioaccumulation was indicated for S. quadricauda, whereas no such influence was significant for C. noctigama. A biphasic pattern for 137 Cs bioaccumulation was discovered in C. noctigama. A rapid 'quasi-steady state' with an effective equilibration time of less than 100 hours was approached during the exponential growth phase. A surge in the uptake occurred when exponential growth ceased, and this pattern was consistent over the range 30 μM to 1.4 mM external [K + ]. Since depletion of external [K + ] was not detected for these treatments, this pattern can only be explained if there are at least two different cellular compartments involved. Although less certain, a second steady-state BCF appeared within two weeks, which seems to be up to one order of magnitude higher than the first. Microcosm experiments with the

Effects of metal-contaminated soils on the accumulation of heavy metals in gotu kola (Centella asiatica) and the potential health risks: a study in Peninsular Malaysia.

Science.gov (United States)

Ong, Ghim Hock; Wong, Ling Shing; Tan, Ai Li; Yap, Chee Kong

2016-01-01

Centella asiatica is a commonly used medicinal plant in Malaysia. As heavy metal accumulation in medicinal plants which are highly consumed by human is a serious issue, thus the assessment of heavy metals in C. asiatica is important for the safety of consumers. In this study, the heavy metal accumulation in C. asiatica and the potential health risks were investigated. Samples of C. asiatica and surface soils were collected from nine different sites around Peninsular Malaysia. The concentration of six heavy metals namely Cd, Cu, Ni, Fe, Pb and Zn were determined by air-acetylene flame atomic absorption spectrophotometer (AAS). The degree of anthropogenic influence was assessed by calculating the enrichment factor (EF) and index of geoaccumulation (Igeo). The heavy metal uptake into the plant was estimated through the calculation of translocation factor (TF), bioconcentration factor (BCF) and correlation study. Estimated daily intakes (EDI) and target hazard quotients (THQ) were used to determine the potential health risk of consuming C. asiatica. The results showed that the overall surface soil was polluted by Cd, Cu and Pb, while the uptake of Zn and Ni by the plants was high. The value of EDI and THQ showed that the potential of Pb toxicity in C. asiatica was high as well. As heavy metal accumulation was confirmed in C. asiatica, daily consumption of the plant derived from polluted sites in Malaysia was not recommended.

Phytoremediation potential of Miscanthus × giganteus and Spartina pectinata in soil contaminated with heavy metals.

Science.gov (United States)

Korzeniowska, Jolanta; Stanislawska-Glubiak, Ewa

2015-08-01

The aim of this work was to assess the suitability of Miscanthus × giganteus and Spartina pectinata link to Cu, Ni, and Zn phytoremediation. A 2-year microplot experiment with the tested grasses growing on metal-contaminated soil was carried out. Microplots with cement borders, measuring 1 × 1 × 1m, were filled with Haplic Luvisols soil. Simulated soil contamination with Cu, Ni, and Zn was introduced in the following doses in mg kg(-1): 0-no metals, Cu1-100, Cu2-200, Cu3-400, Ni1-60, Ni2-100, Ni3-240, Zn1-300, Zn2-600, and Zn3-1200. The phytoremediation potential of grasses was evaluated using a tolerance index (TI), bioaccumulation factor (BF), bioconcentration factor (BCF), and translocation factor (TF). S. pectinata showed a higher tolerance to soil contamination with Cu, Ni, and Zn compared to M. × giganteus. S. pectinata was found to have a high suitability for phytostabilization of Zn and lower suitability of Cu and Ni. M. × giganteus had a lower phytostabilization potential than S. pectinata. The suitability of both grasses for Zn phytoextraction depended on the age of the plants. Both grasses were not suitable for Cu and Ni phytoextraction. The research showed that one-season studies were not valuable for fully assessing the phytoremediation potential of perennial plants.

Screening of native plant species for phytoremediation potential at a Hg-contaminated mining site.

Science.gov (United States)

Marrugo-Negrete, José; Marrugo-Madrid, Siday; Pinedo-Hernández, José; Durango-Hernández, José; Díez, Sergi

2016-01-15

Artisanal and small-scale gold mining (ASGM) is the largest sector of demand for mercury (Hg), and therefore, one of the major sources of Hg pollution in the environment. This study was conducted in the Alacrán gold-mining site, one of the most important ASGM sites in Colombia, to identify native plant species growing in Hg-contaminated soils used for agricultural purposes, and to assess their potential as phytoremediation systems. Twenty-four native plant species were identified and analysed for total Hg (THg) in different tissues (roots, stems, and leaves) and in underlying soils. Accumulation factors (AF) in the shoots, translocation (TF) from roots to shoots, and bioconcentration (BCF) from soil-to-roots were determined. Different tissues from all plant species were classified in the order of decreasing accumulation of Hg as follows: roots > leaves > stems. THg concentrations in soil ranged from 230 to 6320 ng g(-1). TF values varied from 0.33 to 1.73, with high values in the lower Hg-contaminated soils. No correlation was found between soils with low concentrations of Hg and plant leaves, indicating that TF is not a very accurate indicator, since most of the Hg input to leaves at ASGM sites comes from the atmosphere. On the other hand, the BCF ranged from 0.28 to 0.99, with Jatropha curcas showing the highest value. Despite their low biomass production, several herbs and sub-shrubs are suitable for phytoremediation application in the field, due to their fast growth and high AF values in large and easily harvestable plant parts. Among these species, herbs such as Piper marginathum and Stecherus bifidus, and the sub-shrubs J. curcas and Capsicum annuum are promising native plants with the potential to be used in the phytoremediation of soils in tropical areas that are impacted by mining.

The Dessau workshop on bioaccumulation: state of the art, challenges and regulatory implications.

Science.gov (United States)

Treu, Gabriele; Drost, Wiebke; Jöhncke, Ulrich; Rauert, Caren; Schlechtriem, Christian

2015-01-01

Bioaccumulation plays a vital role in understanding the fate of a substance in the environment and is key to the regulation of chemicals in several jurisdictions. The current assessment approaches commonly use the octanol-water partition coefficient (log K OW ) as an indicator for bioaccumulation and the bioconcentration factor (BCF) as a standard criterion to identify bioaccumulative substances show limitations. The log K OW does not take into account active transport phenomena or special structural properties (e.g., amphiphilic substances or dissociating substances) and therefore additional screening criteria are required. Regulatory BCF studies are so far restricted to fish and uptake through the gills. Studies on (terrestrial) air-breathing organisms are missing. Though there are alternative tests such as the dietary exposure bioaccumulation fish test described in the recently revised OECD test guideline 305, it still remains unclear how to deal with results of alternative tests in regulatory decision-making processes. A substantial number of bioaccumulation fish tests are required in regulation. The development of improved test systems following the 3R principles, namely to replace, reduce and refine animal testing, is thus required. All these aspects stress the importance to further develop the assessment of bioaccumulation. The Dessau Workshop on Bioaccumulation which was held from June 26th to 27th 2014, in Dessau, Germany, provided a comprehensive overview of the state of the art of bioaccumulation assessment, provided insights into the problems and challenges addressed by the regulatory authorities and described new research concepts and their regulatory implications. The event was organised by UBA (Dessau, Germany) and Fraunhofer IME (Schmallenberg, Germany). About 50 participants from industry, regulatory bodies and academia listened to 14 lectures on selected topics and joined the plenary discussions.

Sensitivity of species to chemicals: dose-response characteristics for various test types (LC(50), LR(50) and LD(50)) and modes of action.

Science.gov (United States)

Hendriks, A Jan; Awkerman, Jill A; de Zwart, Dick; Huijbregts, Mark A J

2013-11-01

While variable sensitivity of model species to common toxicants has been addressed in previous studies, a systematic analysis of inter-species variability for different test types, modes of action and species is as of yet lacking. Hence, the aim of the present study was to identify similarities and differences in contaminant levels affecting cold-blooded and warm-blooded species administered via different routes. To that end, data on lethal water concentrations LC50, tissue residues LR50 and oral doses LD50 were collected from databases, each representing the largest of its kind. LC50 data were multiplied by a bioconcentration factor (BCF) to convert them to internal concentrations that allow for comparison among species. For each endpoint data set, we calculated the mean and standard deviation of species' lethal level per compound. Next, the means and standard deviations were averaged by mode of action. Both the means and standard deviations calculated depended on the number of species tested, which is at odds with quality standard setting procedures. Means calculated from (BCF) LC50, LR50 and LD50 were largely similar, suggesting that different administration routes roughly yield similar internal levels. Levels for compounds interfering biochemically with elementary life processes were about one order of magnitude below that of narcotics disturbing membranes, and neurotoxic pesticides and dioxins induced death in even lower amounts. Standard deviations for LD50 data were similar across modes of action, while variability of LC50 values was lower for narcotics than for substances with a specific mode of action. The study indicates several directions to go for efficient use of available data in risk assessment and reduction of species testing. Copyright © 2013 Elsevier Inc. All rights reserved.

Evaluation of the transfer and the accumulation of microcystins in tomato (Solanum lycopersicum cultivar MicroTom) tissues using a cyanobacterial extract containing microcystins and the radiolabeled microcystin-LR ("1"4C-MC-LR)

International Nuclear Information System (INIS)

Corbel, Sylvain; Mougin, Christian; Nélieu, Sylvie; Delarue, Ghislaine; Bouaïcha, Noureddine

2016-01-01

Microcystins are the most common cyanotoxins and may be expected wherever blooms of cyanobacteria occur in surface waters. Their persistence both in the irrigation water and in the soil can lead to their transfer and bioaccumulation into agricultural plants. The aim of this work was to investigate microcystin accumulation in Solanum lycopersicum cultivar MicroTom. The plant was exposed to either Microcystis aeruginosa crude extracts containing up to 100 μg eq. MC-LR L"−"1 in a soil–plant system for 90 days or pure radiolabeled "1"4C-MC-LR in a hydroponic condition for 48 h. Toxin bioaccumulation in the soil and different plant tissues was assessed both by the PP2A inhibition assay and by liquid chromatography-mass spectrometry (LC/MS/MS). After 90 days of exposure, microcystins persisted in the soil and their free extractable concentrations accumulated were very low varying between 1.6 and 3.9 μg eq. MC-LR kg"−"1 DW. Free MC-LR was detected only in roots and leaves with concentrations varying between 4.5 and 8.1 μg kg"−"1 DW and between 0.29 and 0.55 μg kg"−"1 DW, respectively. By using radioactivity ("1"4C-MC-LR), the results have reported a growing accumulation of toxins within the organs roots > leaves > stems and allowed them to confirm the absence of MC-LR in fruits after 48 h of exposure. The bioconcentration factor (BCF) was 13.6 in roots, 4.5 in leaves, and 1.4 in stems. On the other hand, the results highlight the presence of two radioactive fractions in different plant tissues. The non-extractable fraction of radioactivity, corresponding to the covalently bound MC-LR, was higher than that of the extractable fraction only in roots and leaves reaching 56% and 71% of the total accumulated toxin, respectively. Therefore, results raise that monitoring programs must monitor the presence of MCs in the irrigation water to avoid the transfer and accumulation of these toxins in crops. - Graphical abstract: Bioconcentration factors in organs of the

Evaluation of the transfer and the accumulation of microcystins in tomato (Solanum lycopersicum cultivar MicroTom) tissues using a cyanobacterial extract containing microcystins and the radiolabeled microcystin-LR ({sup 14}C-MC-LR)

Energy Technology Data Exchange (ETDEWEB)

Corbel, Sylvain [INRA, UMR1402 ECOSYS, F-78850 Thiverval-Grignon (France); AgroParisTech, UMR1402 ECOSYS, F-78850 Thiverval-Grignon (France); Laboratoire Ecologie, Systématique et Evolution, UMR8079, Univ. Paris-Sud/CNRS/AgroParisTech, Université Paris-Sud, F-91405 Orsay (France); Mougin, Christian; Nélieu, Sylvie; Delarue, Ghislaine [INRA, UMR1402 ECOSYS, F-78850 Thiverval-Grignon (France); AgroParisTech, UMR1402 ECOSYS, F-78850 Thiverval-Grignon (France); Bouaïcha, Noureddine, E-mail: noureddine.bouaicha@u-psud.fr [Laboratoire Ecologie, Systématique et Evolution, UMR8079, Univ. Paris-Sud/CNRS/AgroParisTech, Université Paris-Sud, F-91405 Orsay (France)

2016-01-15

Microcystins are the most common cyanotoxins and may be expected wherever blooms of cyanobacteria occur in surface waters. Their persistence both in the irrigation water and in the soil can lead to their transfer and bioaccumulation into agricultural plants. The aim of this work was to investigate microcystin accumulation in Solanum lycopersicum cultivar MicroTom. The plant was exposed to either Microcystis aeruginosa crude extracts containing up to 100 μg eq. MC-LR L{sup −1} in a soil–plant system for 90 days or pure radiolabeled {sup 14}C-MC-LR in a hydroponic condition for 48 h. Toxin bioaccumulation in the soil and different plant tissues was assessed both by the PP2A inhibition assay and by liquid chromatography-mass spectrometry (LC/MS/MS). After 90 days of exposure, microcystins persisted in the soil and their free extractable concentrations accumulated were very low varying between 1.6 and 3.9 μg eq. MC-LR kg{sup −1} DW. Free MC-LR was detected only in roots and leaves with concentrations varying between 4.5 and 8.1 μg kg{sup −1} DW and between 0.29 and 0.55 μg kg{sup −1} DW, respectively. By using radioactivity ({sup 14}C-MC-LR), the results have reported a growing accumulation of toxins within the organs roots > leaves > stems and allowed them to confirm the absence of MC-LR in fruits after 48 h of exposure. The bioconcentration factor (BCF) was 13.6 in roots, 4.5 in leaves, and 1.4 in stems. On the other hand, the results highlight the presence of two radioactive fractions in different plant tissues. The non-extractable fraction of radioactivity, corresponding to the covalently bound MC-LR, was higher than that of the extractable fraction only in roots and leaves reaching 56% and 71% of the total accumulated toxin, respectively. Therefore, results raise that monitoring programs must monitor the presence of MCs in the irrigation water to avoid the transfer and accumulation of these toxins in crops. - Graphical abstract: Bioconcentration

Fate, toxicity and bioconcentration of cadmium on Pseudokirchneriella subcapitata and Lemna minor in mid-term single tests.

Science.gov (United States)

Clément, Bernard; Lamonica, Dominique

2018-03-01

In the frame of a project which consists in modeling a laboratory microcosm under cadmium pressure, we initiated this study on the fate and effects of cadmium in the presence of either the microalga Pseudokirchneriella subcapitata or the duckweed Lemna minor, two organisms of the microcosm. For each organism, growth inhibition tests on a duration of 2-3 weeks were carried out with the objective of linking effects with total dissolved, ionic and internalized forms of cadmium. Numbers of organisms (algal cells or duckweed fronds) in 2-L beakers filled with synthetic nutritive medium containing EDTA were counted during the course of assays, while cadmium concentrations in the water and in the organisms were measured. Free cadmium fraction was calculated using PHREEQC, a computer program for chemical speciation. Results showed that cadmium toxicity to microalgae could be correlated to the free divalent fraction of this metal, limited by the presence of EDTA, and to its concentration in the organisms. Bioconcentration factors for our medium were suggested for P. subcapitata (111,000 on the basis of free cadmium concentration) and L. minor (17,812 on the basis of total dissolved concentration). No effect concentrations were roughly estimated around 400 µg/g for Pseudokirchneriella subcapitata and 200-300 µg/g for Lemna minor. This study is a first step towards a fate model based on chemical speciation for a better understanding of microcosm results.

Mixing regime as a key factor to determine DON formation in drinking water biological treatment.

Science.gov (United States)

Lu, Changqing; Li, Shuai; Gong, Song; Yuan, Shoujun; Yu, Xin

2015-11-01

Dissolved organic nitrogen (DON) can act as precursor of nitrogenous disinfection by-products formed during chlorination disinfection. The performances of biological fluidized bed (continuous stirred tank reactor, CSTR) and bio-ceramic filters (plug flow reactor, PFR) were compared in this study to investigate the influence of mixing regime on DON formation in drinking water treatment. In the shared influent, DON ranged from 0.71mgL(-1) to 1.20mgL(-1). The two biological fluidized bed reactors, named BFB1 (mechanical stirring) and BFB2 (air agitation), contained 0.12 and 0.19mgL(-1) DON in their effluents, respectively. Meanwhile, the bio-ceramic reactors, labeled as BCF1 (no aeration) and BCF2 (with aeration), had 1.02 and 0.81mgL(-1) DON in their effluents, respectively. Comparative results showed that the CSTR mixing regime significantly reduced DON formation. This particular reduction was further investigated in this study. The viable/total microbial biomass was determined with propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) and qPCR, respectively. The results of the investigation demonstrated that the microbes in BFB2 had higher viability than those in BCF2. The viable bacteria decreased more sharply than the total bacteria along the media depth in BCF2, and DON in BCF2 accumulated in the deeper media. These phenomena suggested that mixing regime determined DON formation by influencing the distribution of viable, total biomass, and ratio of viable biomass to total biomass. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assessment of arsenic content in soil, rice grains and groundwater and associated health risks in human population from Ropar wetland, India, and its vicinity.

Science.gov (United States)

Sharma, Sakshi; Kaur, Inderpreet; Nagpal, Avinash Kaur

2017-08-01

In the present study, potential health risks posed to human population from Ropar wetland and its vicinity, by consumption of inorganic arsenic (i-As) via arsenic contaminated rice grains and groundwater, were assessed. Total arsenic (t-As) in soil and rice grains were found in the range of 0.06-0.11 mg/kg and 0.03-0.33 mg/kg, respectively, on dry weight basis. Total arsenic in groundwater was in the range of 2.31-15.91 μg/L. i-As was calculated from t-As using relevant conversion factors. Rice plants were found to be arsenic accumulators as bioconcentration factor (BCF) was observed to be >1 in 75% of rice grain samples. Further, correlation analysis revealed that arsenic accumulation in rice grains decreased with increase in the electrical conductivity of soil. One-way ANOVA, cluster analysis and principal component analysis indicated that both geogenic and anthropogenic sources affected t-As in soil and groundwater. Hazard index and total cancer risk estimated for individuals from the study area were above the USEPA limits of 1.00 and 1.00 × 10 -6 , respectively. Kruskal-Wallis H test indicated that groundwater intake posed significantly higher health risk than rice grain consumption (χ 2 (1) = 17.280, p = 0.00003).

Removal of chromium ions from wastewater by duckweed, Lemna minor L. by using a pilot system with continuous flow.

Science.gov (United States)

Uysal, Y

2013-12-15

The aim of this study was to determine the ability of Lemna minor to remove Cr (VI) ions from wastewater in a continuous flow pond system. This system was used to simulate a wastewater treatment pond and a natural wetland as habitat of plants. In order to find optimal conditions for chromium removal, ponds were operated with aqueous solutions having different pH (4.0-7.0) and chromium concentration of 0.25 mgCr(+6)/L, then plants were exposed to different chromium concentrations (0.25-5.0 mgCr(+6)/L) at pH 4.0. Chromium concentrations, both in biomass and wastewater, were measured and removal efficiency was determined throughout water flow. Growth factors such as growth rates, chlorophyll contents and dry/fresh weight ratios of plants were also determined to measure toxic effects of chromium. The percentages of chromium uptake (PMU) and bioconcentration factors (BCF) were calculated for each run. The highest accumulated chromium concentration (4.423 mgCr/g) was found in plants grown in the first chamber of pond operated at pH 4.0 and 5.0 mgCr/L, while the minimum accumulated chromium concentration (0.122 mgCr/g) was in plants grown in the last chamber of pond operated at pH 4.0 and 0.25 mgCr(+6)/L. Copyright © 2013 Elsevier B.V. All rights reserved.

Radiocesium bioaccumulation in freshwater plankton: Influences of cation concentrations (K{sup +} and Na{sup +}) on direct uptake of {sup 137}Cs in Chlamydomonas, Scenedesmus and Daphnia. Food-chain transfer of {sup 137}Cs from Chlamydomonas to Daphnia at different K{sup +} concentrations

Energy Technology Data Exchange (ETDEWEB)

Hagstroem, J. [Uppsala Univ., Dept. of Limnology, Uppsala (Sweden)

2002-04-01

The influences of cation concentrations (K{sup +} and Na{sup +}) on radiocesium ({sup 137}Cs) bioaccumulation in two freshwater phytoplankton species (Scenedesmus quadricauda and Chlamydomonas noctigama) were systematically investigated in batch-cultures monitored during two weeks. Both species were cultured at 9 {mu}E M{sup -2} s{sup -1} constant illumination at 20 deg. C. The exponential growth phase lasted for more than 100 hours ({mu} {approx_equal} 0.02 h{sup -1} for C. noctigama and 0.03 h{sup -1} for S, quadricauda). Over cation concentration ranges encountered in natural fresh waters ([K{sup +}] from 0.1 {mu}M to 3 mM, [Na{sup +}] from 20 {mu}M to 3 mM), a more than three order of magnitude variation was found for both intake rate and observed bioconcentration factors (BCF) at apparent steady-state (from less than 10{sup 3} to 10{sup 6} L (kg C){sup -1}). For both species, the major effector on BCF and uptake rate was external [K{sup +}], which was inversely proportional to these parameters over wide ranges (1-1000 {mu}M for S. quadricauda and 0.1 to 300 {mu}M for C. noctigama). At concentrations above these ranges K{sup +} still reduced {sup 137} Cs bio-uptake, but less effectively. A minor influence of external [Na{sup +}] on {sup 137}Cs bioaccumulation was indicated for S. quadricauda, whereas no such influence was significant for C. noctigama. A biphasic pattern for {sup 137}Cs bioaccumulation was discovered in C. noctigama. A rapid 'quasi-steady state' with an effective equilibration time of less than 100 hours was approached during the exponential growth phase. A surge in the uptake occurred when exponential growth ceased, and this pattern was consistent over the range 30 {mu}M to 1.4 mM external [K{sup +}]. Since depletion of external [K{sup +}] was not detected for these treatments, this pattern can only be explained if there are at least two different cellular compartments involved. Although less certain, a second steady-state BCF

Vascular aspects of water uptake mechanisms in the toad skin: perfusion, diffusion, confusion

DEFF Research Database (Denmark)

Willumsen, Niels; Viborg, Arne L; Hillyard, Stanley D

2007-01-01

Blood cell flow (BCF) in the water absorbing "seat patch" region of toad skin was measured with laser Doppler flow cytometry. BCF of dehydrated toads increased by a factor of 6-8 when water contact was made and declined gradually as toads rehydrated. Water absorption was initially stimulated...... and declined in parallel with BCF. Water absorption measured during the initial rehydration period did not correlate with BCF and hydrated toads injected with AVT increased water absorption without an increase in BCF indicating the lack of an obligate relation between blood flow and water absorption....... Aquaporins 1-3 were characterized by RT-PCR analysis of seat patch skin. AQP 1 was localized in the endothelium of subepidermal capillaries and serves as a pathway for water absorption in series with the apical and basolateral membranes of the epithelium. Dehydrated toads rehydrated more rapidly from dilute...

Assessment of environmental and health risks in former polymetallic ore mining and smelting area, Slovakia: Spatial distribution and accumulation of mercury in four different ecosystems.

Science.gov (United States)

Árvay, Július; Demková, Lenka; Hauptvogl, Martin; Michalko, Miloslav; Bajčan, Daniel; Stanovič, Radovan; Tomáš, Ján; Hrstková, Miroslava; Trebichalský, Pavol

2017-10-01

Former long-term mining and smelting of pollymetallic ores in the Middle Spiš area caused a serious contamination problem of the environment with heavy metals and metalloids, especially mercury (Hg). Several studies have reported concentration of Hg in the area but this paper provides first detailed characterization of Hg contamination of different environmental components in agricultural, forest, grassland and urban ecosystems. The ecosystems are in different distances from emission sources - former mercury and copper smelting plants in NE Slovakia. Total Hg content was studied in soil/substrate samples (n = 234) and characteristic biological samples (Athyrium filix-femina (L.) Roth, Macrolepiota procera (Scop.) Singer, Boletus edulis Bull., Cyanoboletus pulverulentus (Opat.) Gelardi, Vizzini & Simonini, Triticum aestivum (L.), Poa pratensis (L.)) (n = 234) collected in the above-mentioned ecosystems. The level of contamination and environmental risks were assessed by contamination factor (C f ), index of geoaccumulation (I geo ) and potential environmental risk index (PER). To determine the level of transition of Hg from abiotic to biotic environment, bioconcentration factor (BCF) was used. To determine a health risk resulting from regular and long-term consumption of the locally available species, the results of the Hg content were compared with the Provisional Tolerable Weekly Intake (PTWI) for Hg defined by World Health Organization. The results suggest that almost 63% of the area belong to the very high risk category and 80% of the sampling sites shown very high contamination factor. Geoaccumulation index showed that almost 30% of the area is very strongly contaminated and only 8% is not contaminated with Hg. Spearman's correlation relationship confirmed that the values of PER, BCF, C f and I geo decreased with an increasing distance from the pollution source. The percentage of contribution to PTWI ranged between 5.76-69.0% for adults and 11.5-138% for

Threat of heavy metal pollution in halophytic and mangrove plants of Tamil Nadu, India

Energy Technology Data Exchange (ETDEWEB)

Agoramoorthy, Govindasamy; Chen, F.-A. [Department of Pharmacy, Tajen University, Yanpu, Pingtung 907, Taiwan (China); Hsu, Minna J. [Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung 80424, Taiwan (China)], E-mail: hsumin@mail.nsysu.edu.tw

2008-09-15

Mangrove and halophytic plants occur along the coastal areas of Tamil Nadu, south India and these plants have been used in traditional medicine for centuries. Heavy metals are known to pose a potential threat to terrestrial and aquatic biota. However, little is known on the toxic levels of heavy metals found in mangrove and halophytic plants that are used in traditional medicine in India. To understand heavy metal toxicity, we investigated the bioconcentration factors (BCF) of heavy metals in leaves collected from eight mangroves and five halophytes in the protected Pichavaram mangrove forest reserve in Tamil Nadu State, south India. Data presented in this paper describe the impact of essential (Cu, Fe, Mg, Mn and Zn) and non-essential/environmentally toxic trace metals (Hg, Pb and Sn) in mangrove and halophytic medicinal plants. The concentrations of Pb among 13 plant species were higher than the normal range of contamination reported for plants. The average concentration of Hg in the halophytic plants (0.43 {+-} 0.37 {mu}g/g) was seven times higher than mangrove plants (0.06 {+-} 0.03 {mu}g/g) and it indicated pollutants from industrial sources affecting halophytes more than mangroves. - Metal effects occur in India's mangrove ecosystem.

Phytoremediation of Heavy Metals in Aqueous Solutions

Directory of Open Access Journals (Sweden)

Felix Aibuedefe AISIEN

2010-12-01

Full Text Available One of the major environmental problems is the pollution of water and soil by toxic heavy metals. This study investigated the phytoremediation potential of water hyacinth, for the removal of cadmium (Cd, lead (Pb and zinc (Zn. Water hyacinths were cultured in bore-hole water, supplemented with 5mg/l of Zn and Pb and 1mg/l of Cd at pH 4.5, 6.8 and 8.5. The plants were separately harvested each week for six weeks. The results showed that removal of these metals from solution was fast especially in the first two weeks, after which it became gradual till saturation point was reached. The accumulation of Cd and Zn in leaves and roots increased with increase in pH. The highest accumulation was in the roots with metal concentration of 4870mg/kg, 4150mg/kg and 710mg/kg for Zn, Pb and Cd respectively at pH 8.5. The maximum values of bioconcentration factor (BCF for Zn, Pb and Cd were 1674, 1531 and 1479 respectively, suggesting that water hyacinth was good accumulator of Zn, Pb and Cd, and could be used to treat industrial wastewater contaminated with heavy metals such as Zn, Pb and Cd.

Bioaccumulation and physiological effects of copepods sp. (Eucyclop sp.) fed Chlorella ellipsoides exposed to titanium dioxide (TiO2) nanoparticles and lead (Pb2+).

Science.gov (United States)

Matouke, Moise M; Mustapha, Moshood

2018-05-01

The demand for manufactured products and the derivatives of nanomaterials and non essential metals continue to increase, and as a consequence their presence in fisheries and aquaculture has therefore become a major concern for the risks to which our environment is exposed. The bioaccumulation profile of binary compounds (Titanium dioxide nanoparticles and lead) and their effects on the feeding behaviour of copepods were assessed in a simplified food chain including, the freshwater alga Chlorella ellipsoides and the cyclopoids copepods sp. Our results indicated that Pb and TiO 2 NPs individually and mixed can be transferred from alga to copepods via dietary pathway. The highest bioconcentration factor (748.5) was recorded for Pb in the combined compounds (Pb15 + Ti16.5) μg L -1 and the highest BCF (5.57) recorded for TiO 2 NPs was found in TiO 2 NPs (16.5) alone. Ingestion and filtration rate decreased significantly (p  0.05) in both single and binary treatments. The results demonstrate that the co-exposure of TiO 2 NPs and Pb inhibit the ingestion and filtration of microalgae by cyclopoid copepods sp. and also induce increase of carbohydrate, lipid; GPx, GR and CAT due to stress. Copyright © 2018. Published by Elsevier B.V.

Threat of heavy metal pollution in halophytic and mangrove plants of Tamil Nadu, India

International Nuclear Information System (INIS)

Agoramoorthy, Govindasamy; Chen, F.-A.; Hsu, Minna J.

2008-01-01

Mangrove and halophytic plants occur along the coastal areas of Tamil Nadu, south India and these plants have been used in traditional medicine for centuries. Heavy metals are known to pose a potential threat to terrestrial and aquatic biota. However, little is known on the toxic levels of heavy metals found in mangrove and halophytic plants that are used in traditional medicine in India. To understand heavy metal toxicity, we investigated the bioconcentration factors (BCF) of heavy metals in leaves collected from eight mangroves and five halophytes in the protected Pichavaram mangrove forest reserve in Tamil Nadu State, south India. Data presented in this paper describe the impact of essential (Cu, Fe, Mg, Mn and Zn) and non-essential/environmentally toxic trace metals (Hg, Pb and Sn) in mangrove and halophytic medicinal plants. The concentrations of Pb among 13 plant species were higher than the normal range of contamination reported for plants. The average concentration of Hg in the halophytic plants (0.43 ± 0.37 μg/g) was seven times higher than mangrove plants (0.06 ± 0.03 μg/g) and it indicated pollutants from industrial sources affecting halophytes more than mangroves. - Metal effects occur in India's mangrove ecosystem

Nitrate removal from polluted water by using a vegetated floating system.

Science.gov (United States)

Bartucca, Maria Luce; Mimmo, Tanja; Cesco, Stefano; Del Buono, Daniele

2016-01-15

Nitrate (NO3(-)) water pollution is one of the most prevailing and relevant ecological issues. For instance, the wide presence of this pollutant in the environment is dramatically altering the quality of superficial and underground waters. Therefore, we set up a floating bed vegetated with a terrestrial herbaceous species (Italian ryegrass) with the aim to remediate hydroponic solutions polluted with NO3(-). The floating bed allowed the plants to grow and achieve an adequate development. Ryegrass was not affected by the treatments. On the contrary, plant biomass production and total nitrogen content (N-K) increased proportionally to the amount of NO3(-) applied. Regarding to the water cleaning experiments, the vegetated floating beds permitted to remove almost completely all the NO3(-) added from the hydroponic solutions with an initial concentration of 50, 100 and 150 mg L(-1). Furthermore, the calculation of the bioconcentration factor (BCF) indicated this species as successfully applicable for the remediation of solutions polluted by NO3(-). In conclusion, the results highlight that the combination of ryegrass and the floating bed system resulted to be effective in the remediation of aqueous solutions polluted by NO3(-). Copyright © 2015 Elsevier B.V. All rights reserved.

Mercury in certain boletus mushrooms from Poland and Belarus.

Science.gov (United States)

Falandysz, Jerzy; Krasińska, Grażyna; Pankavec, Sviatlana; Nnorom, Innocent C

2014-01-01

This paper reports the results of the study of Hg contents of four species of Boletus mushroom (Boletus reticulatus Schaeff. 1763, B. pinophilus Pilát & Dermek 1973, B. impolitus Fr. 1838 and B. luridus Schaeff. 1774) and the surface soils (0-10 cm layer, ∼100 g) samples beneath the mushrooms from ten forested areas in Poland and Belarus by cold-vapour atomic absorption spectroscopy. The ability of the species to bioconcentrate Hg was calculated (as the BCF) while Hg intakes from consumption of these mushroom species were also estimated. The median Hg content of the caps of the species varied between 0.38 and 4.7 mg kg(-1) dm; in stipes between 0.13 and 2.5 mg kg(-1) dm and in the mean Hg contents of soils varied from 0.020 ± 0.01 mg kg(-1) dm to 0.17 ± 0.10 mg kg(-1) dm which is considered as "background" Hg level. The median Hg content of caps of B. reticulatus and B. pinophilus were up to 4.7 and 3.6 mg kg(-1) dm, respectively, and they very efficiently bioaccumulate Hg with median BCF values of up to 130 for caps and 58 for stipes. The caps and stipes of these mushrooms if eaten will expose consumer to elevated dose of total Hg estimated at 1.4 mg for caps of Boletus reticulatus from the Kacze Łęgi site, which is a nature reserve area. Nevertheless, the occasional consumption of the valued B. reticulatus and B. pinophilus mushrooms maybe safe.

Bauhinia championii flavone inhibits apoptosis and autophagy via the PI3K/Akt pathway in myocardial ischemia/reperfusion injury in rats.

Science.gov (United States)

Jian, Jie; Xuan, Feifei; Qin, Feizhang; Huang, Renbin

2015-01-01

This study aimed to determine the effects of Bauhinia championii flavone (BCF) on myocardial ischemia/reperfusion injury (MI/RI) in rats and to explore potential mechanisms. The MI/RI model in rats was established by ligating the left anterior descending coronary artery for 30 minutes, then reperfusing for 3 hours. BCF at 20 mg/kg was given 20 minutes prior to ischemia via sublingual intravenous injection, with 24 μg/kg phosphoinositide 3-kinase inhibitor (PI3K; wortmannin) as a control. The creatine kinase-MB and nitric oxide content were assessed by colorimetry. The levels of mitochondrial permeability transition pores and tumor necrosis factor alpha were determined by an enzyme-linked immunosorbent assay. Cardiomyocyte apoptosis was detected by the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Additionally, the expression of PI3K, endothelial nitric oxide synthase, caspase-3, and Beclin1 was analyzed by fluorescence quantitative polymerase chain reaction and Western blotting, respectively. Akt and microtubule-associated protein 1 light chain 3-II protein levels were also evaluated. Pretreatment with BCF significantly decreased the levels of creatine kinase-MB, tumor necrosis factor alpha, and mitochondrial permeability transition pores, but increased the nitric oxide content. Furthermore, BCF inhibited apoptosis, downregulated caspase-3, Beclin1, and microtubule-associated protein 1 light chain 3-II, upregulated PI3K, and increased the protein levels of phosphorylated Akt and endothelial nitric oxide synthase. However, all of the previously mentioned effects of BCF were blocked when BCF was coadministered with wortmannin. In conclusion, these observations indicated that BCF has cardioprotective effects against MI/RI by reducing cell apoptosis and excessive autophagy, which might be related to the activation of the PI3K/Akt signaling pathway.

Trace element accumulation and distribution in sunflower plants at the stages of flower bud and maturity

Directory of Open Access Journals (Sweden)

Susanna De Maria

2013-02-01

Full Text Available The aim of this study was to analyze the accumulation and distribution of cadmium (Cd, zinc (Zn and copper (Cu in different portions of plants of sunflower (Helianthus annuus L., cv. Oleko grown in soil with contaminants (5, 300, 400 mg kg–1 of Cd, Zn and Cu, respectively and without (untreated soil as a control from the emergence of cotyledon leaves until to two phenological stages: flower bud (R-1 and maturity (R- 9. Sunflower accumulated considerable amounts of heavy metals in both phenological stages showing slight reductions of dry matter production. At R-1 stage, Cd, Zn and Cu were accumulated mainly in the roots with concentrations respectively up to 5.4, 233 and 160 mg kg–1 of dry matter with a low translocation from roots to the aerial part. Yet at the R-1 stage, the bioconcentration factor (BCF of Cd showed a significantly higher value in the Cd-Zn-Cu treatment (0.27 with respect to the untreated control (0.02, vice versa was observed for Cu, whereas no significant difference between treatments was observed for Zn (0.12 on average. However among metals, Cd showed the highest value of BCF. Referring only to the epigeous portion, differences in the accumulation and distribution of the three metals in the treated plants were found in both phenological stages; indeed passing from flower bud to the maturity stage, Cd, Zn and Cu concentrations increased in the stems and leaves, particularly in the old ones, whereas decreased in the heads. Metal accumulation in the achenes was very low and never exceed the toxicity threshold value considered for livestock. The high storage of heavy metals in roots and the probable re-translocation of the three metals along the plant during the growing cycle could be considered as a strategy of sunflower to preserve young metabolically-active leaves and reproductive organs from toxic metal concentrations.

Estimation of physicochemical properties of 2-ethylhexyl-4-methoxycinnamate (EHMC) degradation products and their toxicological evaluation.

Science.gov (United States)

Gackowska, Alicja; Studziński, Waldemar; Kudlek, Edyta; Dudziak, Mariusz; Gaca, Jerzy

2018-06-01

The organic UV filters, commonly used in personal protection products, are of concern because of their potential risk to aquatic ecosystems and living organisms. One of UV filters is ethylhexyl-4-methoxycinnamate (EHMC) acid. Studies have shown that, in the presence of oxidizing and chlorinating factors, EHMC forms a series of products with different properties than the substrate. In this study, the toxicities of EHMC and its transformation/degradation products formed under the influence of NaOCl/UV and H 2 O 2 /UV systems in the water medium were tested using Microtox® bioassay and by observation of mortality of juvenile crustaceans Daphnia magna and Artemia Salina. We have observed that oxidation and chlorination products of EHMC show significantly higher toxicity than EHMC alone. The toxicity of chemicals is related to their physicochemical characteristic such as lipophilicity and substituent groups. With the increase in lipophilicity of products, expressed as log K OW , the toxicity (EC 50 ) increases. On the basis of physicochemical properties such as vapour pressure (VP), solubility (S), octanol-water partition coefficient (K OW ), bioconcentration factor (BCF) and half-lives, the overall persistence (P OV ) and long-range transport potential (LRTP) of all the products and EHMC were calculated. It was shown that the most persistent and traveling on the long distances in environment are methoxyphenol chloroderivatives, then methoxybenzene chloroderivatives, EHMC chloroderivatives, methoxybenzaldehyde chloroderivatives and methoxycinnamate acid chloroderivatives. These compounds are also characterised by high toxicity.

Germination and seedling growth of Indian mustard exposed to cadmium and chromium

Directory of Open Access Journals (Sweden)

Luca Marchiol

2006-03-01

Full Text Available To make phytoremediation a technically viable option for large-scale applications we need plants that are able to guarantee high biomass yield as well as high accumulation of heavy metals in their aerial parts. The aim of this investigation was to study the performance of aquacultured plants of Indian mustard in the presence of different concentrations of cadmium and chromium since seed germination. The effects on germination and growth of seedlings of Indian mustard (Brassica juncea L. Czern cv. WNFP, Varuna and Barton, were investigated in/under hydroponic conditions during a 4-week experiment. Cadmium and chromium were provided since germination as cadmium nitrate Cd(NO32 and chromium bichromate K2Cr2O7 (0.5, 1 and 1.5 M. Plant biomass growth measured at the end of the experiments varied with the different metal concentrations in the nutrient solution and the accumulation of the elements in the plant fractions differed significantly among/between cultivars. Ability in the uptake of metals and their mobilization and storage in the aerial plant biomass, expressed by the bioconcentration factor (BCF and translocation factor (TF, respectively, are the most important traits of plants with phytoextraction potential. Brassica juncea was confirmed as being a highly tolerant species, but poor metal translocation values were registered, therefore the high amount of Cd and Cr concentrated in the root systems did not migrate to the aerial, harvestable, part of the plant.

Fiber optically coupled radioluminescence detectors: A short review of key strengths and weaknesses of BCF-60 and Al2O3:C scintillating-material based systems in radiotherapy dosimetry applications

DEFF Research Database (Denmark)

Buranurak, Siritorn; Andersen, Claus E.

2017-01-01

the years, developments and research of the fiber detector systems have undergone in several groups worldwide. In this article, the in-house developed fiber detector systems based on two luminescence phosphors of (i) BCF-60 polystyrene-based organic plastic scintillator and (ii) carbon-doped aluminum oxide...... in the new hybrid MRI LINAC/cobalt systems, and (iii) in vivo measurements due to safety-issues related to the high operating voltage. Fiber optically coupled luminescence detectors provide a promising supplement to ionization chambers by offering the capability of real-time in vivo dose monitoring with high...... time resolution. In particular, the all-optical nature of these detectors is an advantage for in vivo measurements due to the absence of high voltage supply or electrical wire that could cause harm to the patient or disturb the treatment. Basically, fiber-coupled luminescence detector systems function...

Adaptive response of arbuscular mycorrhizal symbiosis to accumulation of elements and translocation in Phragmites australis affected by cadmium stress.

Science.gov (United States)

Huang, Xiaochen; Ho, Shih-Hsin; Zhu, Shishu; Ma, Fang; Wu, Jieting; Yang, Jixian; Wang, Li

2017-07-15

Arbuscular mycorrhizal (AM) fungi have been reported to play a central role in improving plant tolerance to cadmium (Cd)-contaminated sites. This is achieved by enhancing both the growth of host plants and the nutritive elements in plants. This study assessed potential regulatory effects of AM symbiosis with regard to nutrient uptake and transport, and revealed different response strategies to various Cd concentrations. Phragmites australis was inoculated with Rhizophagus irregularis in the greenhouse cultivation system, where it was treated with 0-20 mg L -1 of Cd for 21days to investigate growth parameters, as well as Cd and nutritive element distribution in response to AM fungus inoculation. Mycorrhizal plants showed a higher tolerance, particularly under high Cd-level stress in the substrate. Moreover, our results determined the roots as dominant Cd reservoirs in plants. The AM fungus improved Cd accumulation and saturated concentration in the roots, thus inhibiting Cd uptake to shoots. The observed distributions of nutritive elements and the interactions among these indicated the highest microelement contribution to roots, Ca contributed maximally in leaves, and K and P contributed similarly under Cd stress. In addition, AM fungus inoculation effectively impacted Mn and P uptake and accumulation while coping with Cd toxicity. This study also demonstrated translocation factor from metal concentration (TF) could be a good parameter to evaluate different transportation strategies induced by various Cd stresses in contrast to the bioconcentration factor (BCF) and translocation factor from metal accumulation (TF'). Copyright © 2017 Elsevier Ltd. All rights reserved.

Potential of trees leaf/ bark to control atmospheric metals in a gas and petrochemical zone.

Science.gov (United States)

Safari, Mojgan; Ramavandi, Bahman; Sanati, Ali Mohammad; Sorial, George A; Hashemi, Seyedenayat; Tahmasebi, Saeid

2018-05-22

Leaf and bark of trees are tools for assessing the effects of the heavy metals pollution and monitoring the environmental air quality. The aim of this study was to evaluate the presence of Ni, Pb, V, and Co metals in four tree/shrub species (Conocarpus erectus, Nerium oleander, Bougainvillea spectabilis willd, and Hibiscus rosa-sinensis) in the heavily industrial zone of Asaloyeh, Iran. Two industrial zones (sites 1 and 2), two urban areas (sites 3 and 4), and two rural areas (sites 5 and 6) in the Asaloyeh industrial zone and an uncontaminated area as a control were selected. Sampling from leaf and bark of trees was carried out in spring 2016. The metals content in the washed and unwashed leaf and bark was investigated. The results showed that four studied metals in N. oleander, C. erectus, and B. spectabilis willd in all case sites were significantly higher than that of in the control site (p < 0.05). The highest concentration of metals was found in sites 3, 4, and 6; this was due to dispersion of the pollutants from industrial environments by dominant winds. The highest comprehensive bio-concentration index (CBCI) was found in leaf (0.37) and bark (0.12) of N. oleander. The maximum metal accumulation index (MAI) in the samples was found in leaf of N. oleander (1.58) and in bark of H. rosa-sinensis (1.95). The maximum bio-concentration factor (BCF) was seen for cobalt metal in the N. oleander leaf (0.89). The nickel concentration in washed-leaf samples of C. erectus was measured to be 49.64% of unwashed one. In general, the N. oleander and C. erectus species were found to have the highest absorption rate from the atmosphere and soil than other studied species, and are very suitable tools for managing air pollution in highly industrialized areas. Copyright © 2018 Elsevier Ltd. All rights reserved.

Physical and chemical properties of pyrethroids.

Science.gov (United States)

Laskowski, Dennis A

2002-01-01

The physical and chemical properties of the pyrethroids bifenthrin, cyfluthrin, cypermethrin (also zetacypermethrin), deltamethrin, esfenvalerate (also fenvalerate), fenpropathrin, lambda-cyhalothrin (also cyhalothrin), permethrin, and tralomethrin have been reviewed and summarized in this paper. Physical properties included molecular weight, octanol-water partition coefficient, vapor pressure, water solubility, Henry's law constant, fish biocencentration factor, and soil sorption, desorption, and Freundlich coefficients. Chemical properties included rates of degradation in water as a result of hydrolysis, photodecomposition, aerobic or anaerobic degradation by microorganisms in the absence of light, and also rates of degradation in soil incubated under aerobic or anaerobic conditions. Collectively, the pyrethroids display a highly nonpolar nature of low water solubility, low volatility, high octanol-water partition coefficients, and have high affinity for soil and sediment particulate matter. Pyrethroids have low mobility in soil and are sorbed strongly to the sediments of natural water systems. Although attracted to living organisms because of their nonpolar nature, their capability to bioconcentrate is mitigated by their metabolism and subsequent elimination by the organisms. In fish, bioconcentration factors (BCF) ranged from 360 and 6000. Pyrethroids in water solution tend to be stable at acid and neutral pH but [table: see text] become increasingly susceptible to hydrolysis at pH values beyond neutral. Exceptions at higher pH are bifenthrin (stable), esfenvalerate (stable), and permethrin (half-life, 240 d). Pyrethroids vary in susceptibility to sunlight. Cyfluthrin and tralomethrin in water had half-lives of 0.67 and 2.5 d; lambda-cyhalothrin, esfenvalerate, deltamethrin, permethrin, and cypermethrin were intermediate with a range of 17-110 d; and bifenthrin and fenpropathrin showed the least susceptibility with half-lives of 400 and 600 d, respectively

Accumulation, transfer, and potential sources of mercury in the soil-wheat system under field conditions over the Loess Plateau, northwest China

International Nuclear Information System (INIS)

Wang, Shengli; Nan, Zhongren; Prete, Daniel; Ma, Jianmin; Liao, Qin; Zhang, Qian

2016-01-01

There is limited information on accumulation, transfer, and source of mercury in wheats under field conditions over the Loess Plateau, northwest China. The present study collected 26 pairs of topsoil and whole wheat samples (roots, stems, leaves, shells, and grains) from Dongdagou stream watershed and upper Xidagou stream watershed, Baiyin City, northwest China. Hg concentrations from these samples were used to identify their relationships with soil properties, interactions with other metals, localization of Hg in the different wheat tissues, bio-concentration and transfer of Hg, and major sources of Hg in wheat. Results show that Hg levels in 11 out of 26 sampled soils (42.3% of soil samples) exceeded Hg limit of grade II soil environmental quality standards in China (1.0 mg·kg"− "1). Likewise, it was also found that Hg in over 50% of wheat grain samples reached or exceeded the maximum permissible food safety levels (0.02 mg·kg"− "1) according to the General Standard of Contaminants in Food in China (GB 2762-2012). The spatial distribution pattern of Hg in wheats grains was different from that in the sampled soils. Hg concentrations in different wheat tissues were highest in roots, followed by leaves, stalks, shells, and grains, respectively. Bio-concentration factors (BCF) of Hg in almost all grains samples were one or two orders of magnitude lower than that in roots, except for two wheat samples. The translocation factors (TF) of Hg in wheat tissues on average were leaves > stems > shells > grains. The spatial distribution of Hg and its correlation with other heavy metal detected simultaneously in the soil samples suggested that the Hg soil contamination was probably caused by past sewage irrigation practices and atmospheric deposition. Correlation analysis revealed that the principle source of Hg in wheat roots was very likely from Hg contaminated soils. - Highlights: • Hg concentrations in wheats and corresponding soils from loess plateau, northwest

Accumulation, transfer, and potential sources of mercury in the soil-wheat system under field conditions over the Loess Plateau, northwest China

Energy Technology Data Exchange (ETDEWEB)

Wang, Shengli [Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000 (China); Key Laboratory of Western China' s Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000 (China); Nan, Zhongren, E-mail: nanzhongren@lzu.edu.cn [Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000 (China); Key Laboratory of Western China' s Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000 (China); Prete, Daniel [Department of Chemistry and Biology, Ryerson University, Toronto M5B 2K3 (Canada); Ma, Jianmin; Liao, Qin; Zhang, Qian [Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000 (China)

2016-10-15

There is limited information on accumulation, transfer, and source of mercury in wheats under field conditions over the Loess Plateau, northwest China. The present study collected 26 pairs of topsoil and whole wheat samples (roots, stems, leaves, shells, and grains) from Dongdagou stream watershed and upper Xidagou stream watershed, Baiyin City, northwest China. Hg concentrations from these samples were used to identify their relationships with soil properties, interactions with other metals, localization of Hg in the different wheat tissues, bio-concentration and transfer of Hg, and major sources of Hg in wheat. Results show that Hg levels in 11 out of 26 sampled soils (42.3% of soil samples) exceeded Hg limit of grade II soil environmental quality standards in China (1.0 mg·kg{sup −} {sup 1}). Likewise, it was also found that Hg in over 50% of wheat grain samples reached or exceeded the maximum permissible food safety levels (0.02 mg·kg{sup −} {sup 1}) according to the General Standard of Contaminants in Food in China (GB 2762-2012). The spatial distribution pattern of Hg in wheats grains was different from that in the sampled soils. Hg concentrations in different wheat tissues were highest in roots, followed by leaves, stalks, shells, and grains, respectively. Bio-concentration factors (BCF) of Hg in almost all grains samples were one or two orders of magnitude lower than that in roots, except for two wheat samples. The translocation factors (TF) of Hg in wheat tissues on average were leaves > stems > shells > grains. The spatial distribution of Hg and its correlation with other heavy metal detected simultaneously in the soil samples suggested that the Hg soil contamination was probably caused by past sewage irrigation practices and atmospheric deposition. Correlation analysis revealed that the principle source of Hg in wheat roots was very likely from Hg contaminated soils. - Highlights: • Hg concentrations in wheats and corresponding soils from loess

Bioaccumulation of short chain chlorinated paraffins in a typical freshwater food web contaminated by e-waste in south china: Bioaccumulation factors, tissue distribution, and trophic transfer.

Science.gov (United States)

Sun, Runxia; Luo, Xiaojun; Tang, Bin; Chen, Laiguo; Liu, Yu; Mai, Bixian

2017-03-01

Short chain chlorinated paraffins (SCCPs) are under review for inclusion into the Stockholm Convention on Persistent Organic Pollutants. However, limited information is available on their bioaccumulation and biomagnification in ecosystems, which is hindering evaluation of their ecological and health risks. In the present study, wild aquatic organisms (fish and invertebrates), water, and sediment collected from an enclosed freshwater pond contaminated by electronic waste (e-waste) were analyzed to investigate the bioaccumulation, distribution, and trophic transfer of SCCPs in the aquatic ecosystem. SCCPs were detected in all of the investigated aquatic species at concentrations of 1700-95,000 ng/g lipid weight. The calculated bioaccumulation factors (BAFs) varied from 2.46 to 3.49. The relationship between log BAF and the octanol/water partition coefficient (log K OW ) for benthopelagic omnivorous fish species followed the empirical model of bioconcentration, indicating that bioconcentration plays an important role in accumulation of SCCPs. In contrast, the relationship for the benthic carnivorous fish and invertebrates was not consistent with the empirical model of bioconcentration, implying that the bioaccumulation of SCCPs in these species could be more influenced by other complex factors (e.g., habitat and feeding habit). Preferential distribution in the liver rather than in other tissues (e.g., muscle, gills, skin, and kidneys) was noted for the SCCP congeners with higher log K OW , and bioaccumulation pathway (i.e. water or sediment) can affect the tissue distribution of SCCP congeners. SCCPs underwent trophic dilution in the aquatic food web, and the trophic magnification factor (TMF) values of SCCP congener groups significantly correlated with their corresponding log K OW values (p < 0.0001). The present study results improved our understanding on the environmental behavior and fate of SCCPs in aquatic ecosystem. Copyright © 2016 Elsevier Ltd. All rights

Heavy metal tolerance and accumulation of Triarrhena sacchariflora, a large amphibious ornamental grass.

Science.gov (United States)

Tian, R N; Yu, S; Wang, S G; Zhang, Y; Tang, J Y; Liu, Y L; Nie, Y H

2013-01-01

In this study, we report the tolerance and accumulation of Triarrhena sacchariflora to copper (Cu) and cadmium (Cd). The results show that T. sacchariflora had strong tolerance to Cu and Cd stress. The tolerance indexes (TI) were greater than 0.5 for all treatments. The bioconcentration factors (BCFs) to Cu and Cd were both above 1.0. The accumulation ability of roots was stronger than that of shoots, and ranges of BCF to Cu and Cd in roots were 37.89-79.08 and 83.96-300.57, respectively. However, the translocation ability to Cu and Cd was weak, with more than 86% of Cu or Cd accumulated in roots, suggesting an exclusion strategy for heavy metal tolerance. The uptake efficiency (UE) and translocation efficiency (TE) to Cu and Cd increased linearly as the Cu and Cd concentration in the substrate increased. UE was higher than TE, with a maximum of 2,118.90 μg g(-1) root dry weight (DW) (50 mg L(-1) Cu) and 1,847.51 μg g(-1) root DW (20 mg L(-1)Cd), respectively. The results indicate that T. sacchariflora is a Cu- and Cd-tolerant non-hyperaccumulator plant, suggesting that T. sacchariflora could play an important role in phytoremediation in areas contaminated with Cu and Cd.

Accumulation of heavy metals in soil-crop systems: a review for wheat and corn.

Science.gov (United States)

Wang, Shiyu; Wu, Wenyong; Liu, Fei; Liao, Renkuan; Hu, Yaqi

2017-06-01

The health risks arising from heavy metal pollution (HMP) in agricultural soils have attracted global attention, and research on the accumulation of heavy metals in soil-plant systems is the basis for human health risk assessments. This review studied the accumulation of seven typical heavy metals-Cd, Cr, As, Pb, Hg, Cu, and Zn-in soil-corn and soil-wheat systems. The findings indicated that, in general, wheat was more likely to accumulate heavy metals than corn. Bioconcentration factor (BCF) of the seven heavy metals in wheat and corn grains decreased exponentially with their average concentrations in soil. The seven heavy metals were ranked as follows, in ascending order of accumulation in corn grains: Pb < Cr < Zn < As < Cu < Cd

Pesticide residues in nut-planted soils of China and their relationship between nut/soil.

Science.gov (United States)

Han, Yongxiang; Mo, Runhong; Yuan, Xinyue; Zhong, Donglian; Tang, Fubin; Ye, Caifen; Liu, Yihua

2017-08-01

Twenty-nine pesticide residues in nut-planted soils from China were investigated. One organophosphate (chlorpyrifos) was detected in 5.3% soils, and the residue levels of 7.2 μg/kg to 77.2 μg/kg. The concentrations of six organochlorines (DDT, HCH, endosulfan, quintozene, aldrin and dieldrin) detected in 78.9% soils were 0.6 μg/kg to 90.1 μg/kg. The residue levels of six pyrethroids (bifenthrin, fenpropathrin, cyhalothrin, cypermethrin, fenvalerate and deltamethrin) detected in 65.8% soils were 1.5 μg/kg to 884.3 μg/kg. Triadimefon and buprofezin were found in 71.1% and 52.6% samples, respectively, with the corresponding concentrations of 9.8 μg/kg to 193.7 μg/kg and 87.9 μg/kg to 807.4 μg/kg. The multiple residues were found in 76.3% soils. A significant correlation between pesticide residues in nuts and soils was observed, with the correlation coefficient (r) 0.83 (P < 0.001). In addition, the bioconcentration factor (BCF) values for the explanation of pesticides from soils into nuts were ranged from 0.8 to 16.5. The results showed that some pesticides could accumulate in nut by the uptake effect from soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bioremoval of cadmium by lemna minor in different aquatic conditions

Energy Technology Data Exchange (ETDEWEB)

Uysal, Yagmur [Dept. of Environmental Engineering, Kahramanmaras Sutcu Imam University, Kahramanmaras (Turkey); Taner, Fadime [Dept. of Environmental Engineering, Mersin University, Mersin (Turkey)

2010-04-15

This study was undertaken to determine the cadmium removal efficiency of Lemna minor when it was used for treatment of wastewater having different characteristics, i. e., pH, temperature and cadmium concentration. Plants were cultivated in different pH solutions (4.5-8.0) and temperatures (15-35 C) in the presence of cadmium (0.1-10.0 mg/L) for 168 h. The amount of biomass obtained in the study period, the concentrations of cadmium in the tissues and in the media and net uptake of cadmium by Lemna have been determined for each condition. The percentages of cadmium uptake (PMU) and bioconcentration factors (BCF) were also calculated. The highest accumulation was obtained for the highest cadmium concentration of 10.0 mg Cd/L as 11.668 mg Cd/g at pH 6.0, and as 38.650 mg Cd/g at 35 C and pH 5.0. The cadmium accumulation gradually increased with initial concentration of the medium, but the opposite trend was observed for the PMU. However, the maximum PMU was obtained as 52.2% in the solution with the lowest concentration of 0.1 mg Cd/L. A mathematical model was used to describe the cadmium uptake and the equation obtained was seen to fit the experimental data very well. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

Temperature dependence of plastic scintillators

Science.gov (United States)

Peralta, L.

2018-03-01

Plastic scintillator detectors have been studied as dosimeters, since they provide a cost-effective alternative to conventional ionization chambers. Several articles have reported undesired response dependencies on beam energy and temperature, which provides the motivation to determine appropriate correction factors. In this work, we studied the light yield temperature dependency of four plastic scintillators, BCF-10, BCF-60, BC-404, RP-200A and two clear fibers, BCF-98 and SK-80. Measurements were made using a 50 kVp X-ray beam to produce the scintillation and/or radioluminescence signal. The 0 to 40 °C temperature range was scanned for each scintillator, and temperature coefficients were obtained.

Incorporation of inorganic mercury (Hg²⁺) in pelagic food webs of ultraoligotrophic and oligotrophic lakes: the role of different plankton size fractions and species assemblages.

Science.gov (United States)

Soto Cárdenas, Carolina; Diéguez, Maria C; Ribeiro Guevara, Sergio; Marvin-DiPasquale, Mark; Queimaliños, Claudia P

2014-10-01

In lake food webs, pelagic basal organisms such as bacteria and phytoplankton incorporate mercury (Hg(2+)) from the dissolved phase and pass the adsorbed and internalized Hg to higher trophic levels. This experimental investigation addresses the incorporation of dissolved Hg(2+) by four plankton fractions (picoplankton: 0.2-2.7 μm; pico+nanoplankton: 0.2-20 μm; microplankton: 20-50 μm; and mesoplankton: 50-200 μm) obtained from four Andean Patagonian lakes, using the radioisotope (197)Hg(2+). Species composition and abundance were determined in each plankton fraction. In addition, morphometric parameters such as surface and biovolume were calculated using standard geometric models. The incorporation of Hg(2+) in each plankton fraction was analyzed through three concentration factors: BCF (bioconcentration factor) as a function of cell or individual abundance, SCF (surface concentration factor) and VCF (volume concentration factor) as functions of individual exposed surface and biovolume, respectively. Overall, this investigation showed that through adsorption and internalization, pico+nanoplankton play a central role leading the incorporation of Hg(2+) in pelagic food webs of Andean lakes. Larger planktonic organisms included in the micro- and mesoplankton fractions incorporate Hg(2+) by surface adsorption, although at a lesser extent. Mixotrophic bacterivorous organisms dominate the different plankton fractions of the lakes connecting trophic levels through microbial loops (e.g., bacteria-nanoflagellates-crustaceans; bacteria-ciliates-crustaceans; endosymbiotic algae-ciliates). These bacterivorous organisms, which incorporate Hg from the dissolved phase and through their prey, appear to explain the high incorporation of Hg(2+) observed in all the plankton fractions. Copyright © 2014 Elsevier B.V. All rights reserved.

Multi-species interactions impact the accumulation of weathered 2,2-bis (p-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE) from soil

International Nuclear Information System (INIS)

Kelsey, Jason W.; White, Jason C.

2005-01-01

The impact of interactions between the earthworms Eisenia foetida and Lumbricus terrestris and the plants Cucurbita pepo and Cucurbita maxima on the uptake of weathered p,p'-DDE from soil was determined. Although some combinations of earthworm and plant species caused significant changes in the p,p'-DDE burden in both organisms, the effects were species specific. Contaminant bioconcentration in C. pepo was increased slightly by E. foetida and by 3-fold when the plant was grown with L. terrestris. E. foetida had no effect on the contaminant BCF by C. maxima, but L. terrestris caused a 2-fold reduction in p,p'-DDE uptake by the plant. Contaminant levels in E. foetida and L. terrestris were unaffected by C. pepo. When grown with C. maxima, the concentration of p,p'-DDE decreased by approximately 4-fold and 7-fold in E. foetida and L. terrestris, respectively. The data suggest that the prediction of contaminant bioavailability should consider interactions among species. - Interactions between earthworms and plants affect both the phytoextraction and bioaccumulation of p,p'-DDE in soil

Use of filler limestone and construction and demolition residues for remediating soils contaminated with heavy metals: an assessment by means of plant uptake.

Science.gov (United States)

Banegas, Ascension; Martinez-Sanchez, Maria Jose; Agudo, Ines; Perez-Sirvent, Carmen

2010-05-01

A greenhouse trial was carried out to evaluate the assimilation of heavy metals by three types of horticultural plants (lettuce, broccoli and alfalfa), different parts of which are destined for human and animal consumption (leaves, roots, fruits). The plants were cultivated in four types of soil, one uncontaminated (T1), one soil collected in the surrounding area of Sierra Minera (T2), the third being remediated with residues coming from demolition and construction activities (T3) and the four remediated with filler limestone (T4). To determine the metal content, soil samples were first ground to a fine powder using an agate ball mill. Fresh vegetable samples were separated into root and aboveground biomass and then lyophilized. The DTPA-extractable content was also determined to calculate the bioavailable amount of metal. Finally, the translocation factor (TF) and bioconcentration factor (BCF) were calculated. Arsenic levels were obtained by using atomic fluorescence spectrometry with an automated continuous flow hydride generation (HG-AFS) spectrometer and Cd, Pb and Zn was determined by electrothermal atomization atomic absorption spectrometry (ETAAS) or flame atomic absorption spectrometry (FAAS). Samples of the leached water were also obtained and analyzed. According to our results, the retention of the studied elements varies with the type of plant and is strongly decreased by the incorporation of filler limestone and/or construction and demolition residues to the soils. This practice represents a suitable way to reduce the risk posed to the biota by the presence of high levels of heavy metal in soil.

A preliminary evaluation of some soil and plant parameters that influence root uptake of arsenic, cadmium, cooper, and zinc

International Nuclear Information System (INIS)

Hattemer-Frey, H.A.; Krieger, G.R.; Lau, V.

1994-01-01

In the absence of site-specific data, the concentration of metals in plants is typically estimated by multiplying the total concentration of metal in soil by a metal-specific soil-to-root bioconcentration factor (BCF). However, this approach does not account for various soil properties, such as pH, organic matter content, and cation exchange capacity, that are known to influence root uptake of some metals. For risk assessment purposes, a simple, predictive method for estimating root uptake of metals that is based on site-specific soil and crop data is needed so that the importance of the produce ingestion pathway and subsequent influence on human exposure can be quantitatively assessed. An easy-to-use method is necessary since collecting site-specific data on the concentration of metals in home-grown produce is often time-consuming and costly. Ideally, it should be possible to develop a statistically-reliable relationship between plant and soil metals levels that includes appropriate weighing factors for various soil properties. Multiple linear regression analyses were used to develop simple, predictive models for estimating the concentration of metals in plants via root uptake using site-specific soil data. This paper presents preliminary predictive equations for estimating root uptake of arsenic, cadmium, copper, and zinc in fruiting, root, and all vegetables combined (i.e., fruiting and root crop data were combined). Results show that by using data on additional soil parameters (other than relying solely on the concentration of metals in soil), the concentration of metals in fruiting and root vegetables can be more confidently predicted

Phytofiltration of cadmium from water by Limnocharis flava (L.) Buchenau grown in free-floating culture system

International Nuclear Information System (INIS)

Abhilash, P.C.; Pandey, Vimal Chandra; Srivastava, Pankaj; Rakesh, P.S.; Chandran, Smitha; Singh, Nandita; Thomas, A.P.

2009-01-01

A hydroponics experiment was conducted to examine the phytofiltration of Cd by Limnocharis flava (L.) Buchenau grown in low-level Cd-contaminated water. For this, 45 d old seedlings of L .flava were transferred to a floating-support culture system containing nutrient solution spiked with four levels of Cd (0.5, 1, 2 and 4 mg l -1 ) and were separately harvested after 3, 7, 21 and 30 d. After 30 d harvesting, the percentage removal of Cd from the above four treatments reached up to 98, 96, 95 and 93%, respectively. Interestingly, all treatments had higher growth rate than control at 95% confidence level and plants still remained healthy at 4 mg l -1 Cd exposure. The bioaccumulation study showed a linear relationship of Cd (R 2 = 0.896-0.999) in all plant parts with the exposure time (3-30 d) and Cd concentrations in hydroponics system (0.5-4 mg l -1 ). Although, the root of L. flava had higher Cd concentration than leaf and peduncles, the total Cd concentrations in aerial plant parts were higher than the roots. The maximum bioconcentration factor (BCF) and translocation factor (TF) value of L. flava were calculated as 984.42 and 1.43, respectively. Estimated Cd accumulation capacity of L. flava per unit area (m 2 ) was found to be in the range of 218. 35-1698.92 mg m -2 .The experimental results demonstrated that L. flava is a suitable candidate for the phytofiltartion (>93%) of Cd from low-level Cd-contaminated water.

Phytofiltration of cadmium from water by Limnocharis flava (L.) Buchenau grown in free-floating culture system

Energy Technology Data Exchange (ETDEWEB)

Abhilash, P.C., E-mail: pcabhilash@gmail.com [Eco-Auditing Group, National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow-226 001, Uttar Pradesh (India); School of Environmental Sciences, Mahatma Gandhi University, Priyadharshini Hills P.O., Kottayam- 686 008, Kerala (India); Pandey, Vimal Chandra; Srivastava, Pankaj [Eco-Auditing Group, National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow-226 001, Uttar Pradesh (India); Rakesh, P.S.; Chandran, Smitha [School of Environmental Sciences, Mahatma Gandhi University, Priyadharshini Hills P.O., Kottayam-686 008, Kerala (India); Singh, Nandita [Eco-Auditing Group, National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow-226 001, Uttar Pradesh (India); Thomas, A.P. [School of Environmental Sciences, Mahatma Gandhi University, Priyadharshini Hills P.O., Kottayam-686 008, Kerala (India)

2009-10-30

A hydroponics experiment was conducted to examine the phytofiltration of Cd by Limnocharis flava (L.) Buchenau grown in low-level Cd-contaminated water. For this, 45 d old seedlings of L .flava were transferred to a floating-support culture system containing nutrient solution spiked with four levels of Cd (0.5, 1, 2 and 4 mg l{sup -1}) and were separately harvested after 3, 7, 21 and 30 d. After 30 d harvesting, the percentage removal of Cd from the above four treatments reached up to 98, 96, 95 and 93%, respectively. Interestingly, all treatments had higher growth rate than control at 95% confidence level and plants still remained healthy at 4 mg l{sup -1} Cd exposure. The bioaccumulation study showed a linear relationship of Cd (R{sup 2} = 0.896-0.999) in all plant parts with the exposure time (3-30 d) and Cd concentrations in hydroponics system (0.5-4 mg l{sup -1}). Although, the root of L. flava had higher Cd concentration than leaf and peduncles, the total Cd concentrations in aerial plant parts were higher than the roots. The maximum bioconcentration factor (BCF) and translocation factor (TF) value of L. flava were calculated as 984.42 and 1.43, respectively. Estimated Cd accumulation capacity of L. flava per unit area (m{sup 2}) was found to be in the range of 218. 35-1698.92 mg m{sup -2}.The experimental results demonstrated that L. flava is a suitable candidate for the phytofiltartion (>93%) of Cd from low-level Cd-contaminated water.

Phytoremediation potential of wild plants growing on soil contaminated with heavy metals.

Science.gov (United States)

Čudić, Vladica; Stojiljković, Dragoslava; Jovović, Aleksandar

2016-09-01

Phytoremediation is an emerging technology that employs higher plants to cleanup contaminated environments, including metal-polluted soils. Because it produces a biomass rich in extracted toxic metals, further treatment of this biomass is necessary. The aim of our study was to assess the five-year potential of the following native wild plants to produce biomass and remove heavy metals from a polluted site: poplar (Populus ssp.), ailanthus (Ailanthus glandulosa L.), false acacia (Robinia pseudoacacia L.), ragweed (Artemisia artemisiifolia L.), and mullein (Verbascum thapsus L). Average soil contamination with Pb, Cd, Zn, Cu, Ni, Cr, and As in the root zone was 22,948.6 mg kg-1, 865.4 mg kg-1, 85,301.7 mg kg-1, 3,193.3 mg kg-1, 50.7 mg kg-1, 41.7 mg kg-1,and 617.9 mg kg-1, respectively. We measured moisture and ash content, concentrations of Pb, Cd, Zn, Cu, Ni, Cr, and As in the above-ground parts of the plants and in ash produced by combustion of the plants, plus gross calorific values. The plants' phytoextraction and phytostabilisation potential was evaluated based on their bioconcentration factor (BCF) and translocation factor (TF). Mullein was identified as a hyperaccumulator for Cd. It also showed a higher gross calorific value (19,735 kJ kg-1) than ragweed (16,469 kJ kg-1).The results of this study suggest that mullein has a great potential for phytoextraction and for biomass generation, and that ragweed could be an effective tool of phytostabilisation.

Phytofiltration of cadmium from water by Limnocharis flava (L.) Buchenau grown in free-floating culture system.

Science.gov (United States)

Abhilash, P C; Pandey, Vimal Chandra; Srivastava, Pankaj; Rakesh, P S; Chandran, Smitha; Singh, Nandita; Thomas, A P

2009-10-30

A hydroponics experiment was conducted to examine the phytofiltration of Cd by Limnocharis flava (L.) Buchenau grown in low-level Cd-contaminated water. For this, 45 d old seedlings of L .flava were transferred to a floating-support culture system containing nutrient solution spiked with four levels of Cd (0.5, 1, 2 and 4 mg l(-1)) and were separately harvested after 3, 7, 21 and 30 d. After 30 d harvesting, the percentage removal of Cd from the above four treatments reached up to 98, 96, 95 and 93%, respectively. Interestingly, all treatments had higher growth rate than control at 95% confidence level and plants still remained healthy at 4 mg l(-1) Cd exposure. The bioaccumulation study showed a linear relationship of Cd (R(2)=0.896-0.999) in all plant parts with the exposure time (3-30 d) and Cd concentrations in hydroponics system (0.5-4 mg l(-1)). Although, the root of L. flava had higher Cd concentration than leaf and peduncles, the total Cd concentrations in aerial plant parts were higher than the roots. The maximum bioconcentration factor (BCF) and translocation factor (TF) value of L. flava were calculated as 984.42 and 1.43, respectively. Estimated Cd accumulation capacity of L. flava per unit area (m(2)) was found to be in the range of 218. 35-1698.92 mg m(-2).The experimental results demonstrated that L. flava is a suitable candidate for the phytofiltartion (>93%) of Cd from low-level Cd-contaminated water.

Bioaccumulation of trace metals in farmed pacific oysters Crassostrea gigas from SW Gulf of California coast, Mexico.

Science.gov (United States)

Jonathan, M P; Muñoz-Sevilla, N P; Góngora-Gómez, Andrés Martin; Luna Varela, Raquel Gabriela; Sujitha, S B; Escobedo-Urías, D C; Rodríguez-Espinosa, P F; Campos Villegas, Lorena Elizabeth

2017-11-01

The aim of the study was to evaluate the bioavailability of trace metals (Chromium, Copper, Nickel, Lead, Zinc, Cadmium, Arsenic, and Mercury) in the commercially consumed Crassostrea gigas oysters collected over a 12-month growth period (2011-12) from an experimental cultivation farm in La Pitahaya, Sinaloa State, Mexico. Sediment and water samples were also collected from four different zones adjacent to the cultivation area to identify the concentration patterns of metals. The results revealed that sewage disposals, fertilizers used for agricultural practices and shrimp culture are the major sources for the enrichment of certain toxic metals. The metal concentrations in oysters presented a decreasing order of abundance (all values in mg Kg -1 ): Zn (278.91 ± 93.03) > Cu (63.13 ± 31.72) > Cr (22.29 ± 30.23) > Cd (14.54 ± 4.28) > Ni (9.41 ± 11.33) > Pb (2.22 ± 1.33) > As (0.58 ± 0.91) > Hg (0.04 ± 0.06). Bioconcentration Factor (BCF) and Biota Sediment Accumulation Factor (BSAF) exhibited that C. gigas in the region are strong accumulators for Zn and Cd respectively. Thus, the present study proves to fulfill the gap in understanding the rate of bioaccumulation of metals in C. gigas which is regarded as the most sought after oyster species globally. Copyright © 2017 Elsevier Ltd. All rights reserved.

A modified parallel artificial membrane permeability assay for evaluating the bioconcentration of highly hydrophobic chemicals in fish.

Science.gov (United States)

Kwon, Jung-Hwan; Escher, Beate I

2008-03-01

Low cost in vitro tools are needed at the screening stage of assessment of bioaccumulation potential of new and existing chemicals because the number of chemical substances that needs to be tested highly exceeds the capacity of in vivo bioconcentration tests. Thus, the parallel artificial membrane permeability assay (PAMPA) system was modified to predict passive uptake/ elimination rate in fish. To overcome the difficulties associated with low aqueous solubility and high membrane affinity of highly hydrophobic chemicals, we measured the rate of permeation from the donor poly(dimethylsiloxane)(PDMS) disk to the acceptor PDMS disk through aqueous and PDMS membrane boundary layers and term the modified PAMPA system "PDMS-PAMPA". Twenty chemicals were selected for validation of PDMS-PAMPA. The measured permeability is proportional to the passive elimination rate constant in fish and was used to predict the "minimum" in vivo elimination rate constant. The in vivo data were very close to predicted values except for a few polar chemicals and metabolically active chemicals, such as pyrene and benzo[a]pyrene. Thus, PDMS-PAMPA can be an appropriate in vitro system for nonmetabolizable chemicals. Combination with metabolic clearance rates using a battery of metabolic degradation assays would enhance the applicability for metabolizable chemicals.

Accounting for dissociation and photolysis: a review of the algal toxicity of triclosan.

Science.gov (United States)

Roberts, Jayne; Price, Oliver R; Bettles, Nicola; Rendal, Cecilie; van Egmond, Roger

2014-11-01

Triclosan, an antimicrobial agent commonly used in down-the-drain consumer products, is toxic to freshwater microalgae. However, the rapid photolysis and pH-dependent dissociation of this compound may give rise to uncertainty in growth inhibition tests with freshwater microalgae, if these are not well characterized. Methods are presented to minimize these uncertainties by stabilizing pH with an organic buffering agent (Bis-Tris) and by the application of ultraviolet (UV) covers to remove UV wavelengths. Toxicity tests with these methods were in compliance with the validity criteria of the Organisation for Economic Co-operation and Development test 201, and no negative effects were seen in controls relative to the unmodified method. The methods were used for toxicity tests with triclosan at pH levels of 7.0, 8.0, and 8.5, yielding effective concentration, 10% values of 0.5 µg/L, 0.6 µg/L, and 12.1 µg/L, respectively. The observed change in toxicity with pH was proportional to the change in bioconcentration factor (BCF) as calculated using the cell model (a dynamic flux model based on the Fick-Nernst-Planck equations, in this case parameterized for an algal cell). Effect concentrations produced with the methods presented in the present study offer robust data on which to base risk assessment, and it is suggested that similar approaches be used to minimize uncertainty when other compounds that dissociate and photolyse are tested. © 2014 SETAC.

Effect of transpiration on plant accumulation and translocation of PPCP/EDCs

International Nuclear Information System (INIS)

Dodgen, Laurel K.; Ueda, Aiko; Wu, Xiaoqin; Parker, David R.; Gan, Jay

2015-01-01

The reuse of treated wastewater for agricultural irrigation in arid and hot climates where plant transpiration is high may affect plant accumulation of pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs). In this study, carrot, lettuce, and tomato plants were grown in solution containing 16 PPCP/EDCs in either a cool-humid or a warm-dry environment. Leaf bioconcentration factors (BCF) were positively correlated with transpiration for chemical groups of different ionized states (p < 0.05). However, root BCFs were correlated with transpiration only for neutral PPCP/EDCs (p < 0.05). Neutral and cationic PPCP/EDCs showed similar accumulation, while anionic PPCP/EDCs had significantly higher accumulation in roots and significantly lower accumulation in leaves (p < 0.05). Results show that plant transpiration may play a significant role in the uptake and translocation of PPCP/EDCs, which may have a pronounced effect in arid and hot climates where irrigation with treated wastewater is common. - Highlights: • Leaf accumulation of PPCP/EDCs is related on plant transpiration. • Cationic and neutral PPCP/EDCs have similar leaf and root accumulation. • Anionic PPCP/EDCs have greater root accumulation and lesser leaf accumulation. • PPCP/EDCs are extensively metabolized in plant tissue and hydroponic solution. - High plant transpiration in arid and hot areas may lead to increased foliar accumulation of PPCP/EDCs from treated wastewater irrigation

Soil-plant transfer models for metals to improve soil screening value guidelines valid for São Paulo, Brazil.

Science.gov (United States)

Dos Santos-Araujo, Sabrina N; Swartjes, Frank A; Versluijs, Kees W; Moreno, Fabio Netto; Alleoni, Luís R F

2017-11-07

In Brazil, there is a lack of combined soil-plant data attempting to explain the influence of specific climate, soil conditions, and crop management on heavy metal uptake and accumulation by plants. As a consequence, soil-plant relationships to be used in risk assessments or for derivation of soil screening values are not available. Our objective in this study was to develop empirical soil-plant models for Cd, Cu, Pb, Ni, and Zn, in order to derive appropriate soil screening values representative of humid tropical regions such as the state of São Paulo (SP), Brazil. Soil and plant samples from 25 vegetable species in the production areas of SP were collected. The concentrations of metals found in these soil samples were relatively low. Therefore, data from temperate regions were included in our study. The soil-plant relations derived had a good performance for SP conditions for 8 out of 10 combinations of metal and vegetable species. The bioconcentration factor (BCF) values for Cd, Cu, Ni, Pb, and Zn in lettuce and for Cd, Cu, Pb, and Zn in carrot were determined under three exposure scenarios at pH 5 and 6. The application of soil-plant models and the BCFs proposed in this study can be an important tool to derive national soil quality criteria. However, this methodological approach includes data assessed under different climatic conditions and soil types and need to be carefully considered.

Copper uptake kinetics and regulation in a marine fish after waterborne copper acclimation

International Nuclear Information System (INIS)

Dang Fei; Zhong Huan; Wang Wenxiong

2009-01-01

The uptake kinetics and regulation of copper in a marine predatory fish, the black sea bream Acanthopagrus schlegeli after acclimation to waterborne Cu were examined, using radiotracer techniques. The dissolved Cu uptake followed a linear pattern during the time of exposure, and the calculated uptake rate constant was 6.24 L kg -1 day -1 . The efflux rate constant was 0.091 day -1 following dietary uptake of Cu, and the dietary assimilation efficiency (AE) of Cu varied between 1.7% and 10.9% after the fish were fed with three types of prey (oysters, clams and brine shrimp). After the fish were acclimated at a nominal concentration of 50 μg Cu L -1 for 14 days, the Cu uptake rate and efflux rate constant did not change significantly, but the Cu body concentrations and metallothionein (MT) concentrations in fish tissues increased significantly. Subcellular Cu distributions were also modified. Significant MT induction was observed in response to increased Cu tissue concentrations, indicating that MT rather than the uptake kinetics may play a primary role in Cu regulation during waterborne Cu acclimation in this marine fish. Moreover, the high Cu efflux may also be important in Cu regulation during long-term exposure. Our modeling calculations indicated that dietary uptake was likely to be the main route for Cu bioaccumulation in the fish, and the relative contribution of waterborne and dietary uptake depended on the bioconcentration factor (BCF) of the prey and ingestion rate of fish.

Relationship between concentration of rare earth elements in soil and their distribution in plants growing near a frequented road.

Science.gov (United States)

Mleczek, Patrycja; Borowiak, Klaudia; Budka, Anna; Niedzielski, Przemysław

2018-06-05

Rare earth elements (REEs) are a group of elements whose concentration in numerous environmental matrices continues to increase; therefore, the use of biological methods for their removal from soil would seem to be a safe and reasonable approach. The aim of this study was to estimate the phytoextraction efficiency and distribution of light and heavy (LREEs and HREEs) rare earth elements by three herbaceous plant species: Artemisia vulgaris L., Taraxacum officinale F.H. Wigg. and Trifolium repens L., growing at a distance of 1, 10, and 25 m from the edge of a frequented road in Poland. The concentration of REEs in soil and plants was highly correlated (r > 0.9300), which indicates the high potential of the studied plant species to phytoextraction of these elements. The largest proportion of REEs was from the group of LREEs, whereas HREEs comprised only an inconsiderable portion of the REEs group. The dominant elements in the group of LREEs were Nd and Ce, while Er was dominant in the HREEs group. Differences in the amounts of these elements influenced the total concentration of LREEs, HREEs, and finally REEs and their quantities which decreased with distance from the road. According to the Friedman rank sum test, significant differences in REEs concentration, mainly between A. vulgaris L., and T. repens L. were observed for plants growing at all three distances from the road. The same relation between A. vulgaris L. and T. officinale was observed. The efficiency of LREEs and REEs phytoextraction in the whole biomass of plants growing at all distances from the road was A. vulgaris L. > T. officinale L. > T. repens L. For HREEs, the same relationship was recorded only for plants growing at the distance 1 m from the road. Bioconcentration factor (BCF) values for LREEs and HREEs were respectively higher and lower than 1 for all studied plant species regardless of the distance from the road. The studied herbaceous plant species were able to effectively phytoextract

Uptake and elimination kinetics of perfluoroalkyl substances in submerged and free-floating aquatic macrophytes: Results of mesocosm experiments with Echinodorus horemanii and Eichhornia crassipes.

Science.gov (United States)

Pi, N; Ng, J Z; Kelly, B C

2017-06-15

Studies investigating the bioaccumulation behavior of perfluoroalkyl substances (PFASs) in aquatic macrophytes are limited. The present study involved controlled mesocosm experiments to assess uptake and elimination rate constants (k u, k e ), bioconcentration factors (BCFs) and translocation factors (TFs) of several perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkane sulfonic acids (PFSAs) in two aquatic plant species, including one submerged species (Echinodorus horemanii) and one free-floating species (Eichhornia crassipes). The results indicated all PFASs were readily accumulated in these aquatic macrophytes. k u and BCFs increased with increasing perfluoroalkyl chain length. For PFCAs and PFSAs with identical perfluoroalkyl chain length, the corresponding PFSA exhibited higher bioaccumulation potential. On a whole-plant basis, the bioaccumulation potential of PFASs in submerged and free-floating macrophytes were comparable, indicating sorption to plant biomass is similar in the different species. Conversely, when considering accumulation in foliage, BCFs in the free-floating macrophyte were substantially lower compared to submerged species, especially for longer-chain PFASs. Compounds with shorter perfluoroalkyl chain length (PFBS, PFPeA and PFHxA) exhibited preferential translocation to leaf tissue (TFs >1). BCFs exhibited a sigmoidal relationship with pefluoroalkyl chain length, membrane-water distribution coefficients (D mw ), protein-water distribution coefficients (D pw ) and organic-water partition coefficients (K oc ). For these trends, maximum BCF values were exhibited by long-chain PFCAs, with a log D mw , log D pw and log K oc of 6.47, 5.72 and 5.04, respectively. These findings are useful for future design and implementation of phytoremediation systems, as well for future develop of mechanistic models for predicting the environmental fate and distribution of these contaminants of concern. Copyright © 2017. Published by Elsevier Ltd.

Assessment of nickel bioavailability through chemical extractants and red clover (Trifolium pratense L.) in an amended soil: Related changes in various parameters of red clover.

Science.gov (United States)

Shahbaz, Ali Khan; Iqbal, Muhammad; Jabbar, Abdul; Hussain, Sabir; Ibrahim, Muhammad

2018-03-01

Application of immobilizing agents may efficiently reduce the bioavailability of nickel (Ni) in the soil. Here we report the effect of biochar (BC), gravel sludge (GS) and zeolite (ZE) as a sole treatment and their combinations on the bioavailability of Ni after their application into a Ni-polluted soil. The bioavailability of Ni after the application of immobilizing agents was assessed through an indicator plant (red clover) and chemical indicators of bioavailability like soil water extract (SWE), DTPA and Ca(NO 3 ) 2 extracts. Additionally, the effects of Ni bioavailability and immobilizing agents on the growth, physiological and biochemical attributes of red clover were also observed. Application of ZE significantly reduced Ni concentrations in all chemical extracts compared to rest of the treatments. Similarly, the combined application of BC and ZE (BC+ ZE) significantly reduced Ni concentrations, reactive oxygen species (ROS) whereas, significant enhancement in the growth, physiological and biochemical attributes along with an improvement in antioxidant defence machinery of red clover plant, compared to rest of the treatments, were observed. Furthermore, BC+ ZE treatment significantly reduced bioconcentration factor (BCF) and bioaccumulation factor (BAF) of Ni in red clover, compared to rest of the treatments. The Ni concentrations in red clover leaves individually reflected a good correlation with Ni concentrations in the extracts (SWE at R 2 =0.79, DTPA extract at R 2 =0.84 and Ca(NO 3 ) 2 extracts at R 2 =0.86). Our results indicate that combined application of ZE and BC can significantly reduce the Ni bioavailability in the soil while in parallel improve the antioxidant defence mechanism in plants. Copyright © 2017 Elsevier Inc. All rights reserved.

Seaweeds as bioindicators of heavy metals off a hot spot area on the Egyptian Mediterranean Coast during 2008-2010.

Science.gov (United States)

Shams El-Din, N G; Mohamedein, L I; El-Moselhy, Kh M

2014-09-01

Concentrations of Cu, Zn, Cd, Pb, Ni, Co, Fe, Mn, and Hg were measured successively in water, sediments, and six macroalgal species belonging to three algal classes during 3 years (2008-2010) from Abu Qir Bay, Alexandria, Egypt: Chlorophyceae (Enteromorpha compressa, Ulva fasciata), Phaeophyceae (Padina boryana), and Rhodophyceae (Jania rubens, Hypnea musciformis, Pterocladia capillacea). The study aimed to assess the bioaccumulation potential of the seaweeds, as well as to evaluate the extent of heavy metal contamination in the selected study site. Metals were analyzed using atomic absorption spectrophotometry coupled with MH-10 hydride system. The obtained data showed that the highest mean concentrations of Cu, Zn, Fe, and Mn were recorded in E. compressa; Cd, Ni, and Hg exhibited their highest mean concentrations in P. boryana, while Pb and Co were found in J. rubens. Abundance of the heavy metals in the algal species was as follow: Fe > Mn > Zn > Pb > Ni > Co > Cu > Cd > Hg. E. compressa showed the maximum metal pollution index (MPI) which was 11.55. Bioconcentration factor (BCF) for the metals in algae was relatively high with a maximum value for Mn. The Tomlinson pollution load index (PLI) values for the recorded algal species were low, which ranged between 1.00 in P. boryana and 2.72 in E. compressa. Enrichment factors for sediments were low fluctuating between 0.43 for Hg to 2.33 for Mn. Accordingly, the green alga E. compressa, brown alga P. boryana, and red alga J. rubens can be nominated as bioindicators. Based on MPI and PLI indices, Abu Qir Bay in the present study is considered as low-contaminated area.

A probabilistic model for deriving soil quality criteria based on secondary poisoning of top predators. I. Model description and uncertainty analysis.

Science.gov (United States)

Traas, T P; Luttik, R; Jongbloed, R H

1996-08-01

In previous studies, the risk of toxicant accumulation in food chains was used to calculate quality criteria for surface water and soil. A simple algorithm was used to calculate maximum permissable concentrations [MPC = no-observed-effect concentration/bioconcentration factor(NOEC/BCF)]. These studies were limited to simple food chains. This study presents a method to calculate MPCs for more complex food webs of predators. The previous method is expanded. First, toxicity data (NOECs) for several compounds were corrected for differences between laboratory animals and animals in the wild. Second, for each compound, it was assumed these NOECs were a sample of a log-logistic distribution of mammalian and avian NOECs. Third, bioaccumulation factors (BAFs) for major food items of predators were collected and were assumed to derive from different log-logistic distributions of BAFs. Fourth, MPCs for each compound were calculated using Monte Carlo sampling from NOEC and BAF distributions. An uncertainty analysis for cadmium was performed to identify the most uncertain parameters of the model. Model analysis indicated that most of the prediction uncertainty of the model can be ascribed to uncertainty of species sensitivity as expressed by NOECs. A very small proportion of model uncertainty is contributed by BAFs from food webs. Correction factors for the conversion of NOECs from laboratory conditions to the field have some influence on the final value of MPC5, but the total prediction uncertainty of the MPC is quite large. It is concluded that the uncertainty in species sensitivity is quite large. To avoid unethical toxicity testing with mammalian or avian predators, it cannot be avoided to use this uncertainty in the method proposed to calculate MPC distributions. The fifth percentile of the MPC is suggested as a safe value for top predators.

Copper uptake kinetics and regulation in a marine fish after waterborne copper acclimation

Energy Technology Data Exchange (ETDEWEB)

Dang Fei; Zhong Huan [AMCE and Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong); Wang Wenxiong, E-mail: wwang@ust.hk [AMCE and Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong)

2009-09-14

The uptake kinetics and regulation of copper in a marine predatory fish, the black sea bream Acanthopagrus schlegeli after acclimation to waterborne Cu were examined, using radiotracer techniques. The dissolved Cu uptake followed a linear pattern during the time of exposure, and the calculated uptake rate constant was 6.24 L kg{sup -1} day{sup -1}. The efflux rate constant was 0.091 day{sup -1} following dietary uptake of Cu, and the dietary assimilation efficiency (AE) of Cu varied between 1.7% and 10.9% after the fish were fed with three types of prey (oysters, clams and brine shrimp). After the fish were acclimated at a nominal concentration of 50 {mu}g Cu L{sup -1} for 14 days, the Cu uptake rate and efflux rate constant did not change significantly, but the Cu body concentrations and metallothionein (MT) concentrations in fish tissues increased significantly. Subcellular Cu distributions were also modified. Significant MT induction was observed in response to increased Cu tissue concentrations, indicating that MT rather than the uptake kinetics may play a primary role in Cu regulation during waterborne Cu acclimation in this marine fish. Moreover, the high Cu efflux may also be important in Cu regulation during long-term exposure. Our modeling calculations indicated that dietary uptake was likely to be the main route for Cu bioaccumulation in the fish, and the relative contribution of waterborne and dietary uptake depended on the bioconcentration factor (BCF) of the prey and ingestion rate of fish.

[Phytoremediation of mercury and cadmium polluted wetland by Arundo donax].

Science.gov (United States)

Han, Zhiping; Hu, Xiaobin; Hu, Zhenghai

2005-05-01

With a pot culture of simulated mercury (Hg) and cadmium (Cd)-polluted wetland, this paper studied the capability of Arundo donax in accumulating these heavy metals, and their distribution in the plant. The results showed that after grown in a 101 mg.kg(-1) Hg-polluted wetland for 8 months, the Hg-concentrating capability of Arundo donax was in order of root > stem > leaf, and the Hg concentration in its aboveground parts was 200 +/- 20 mg.kg(-1) (DW); while in the case of 115 mg.kg(-1) Cd-pollution, the Cd-concentrating capability was in order of leaf > root > stem, and the Cd concentration in leaf was 160 +/- 26 mg.kg(-1) (DW). The heavy metals concentration in Arundo donax organs increased with its growth time, being 30%-50% higher for 8 months than for 4 months. The BCF (Bio-concentration factor) decreased with increasing heavy metals concentration. In polluted wetland, the BCFs of Hg by the leaf and stem were 1.9 and 2.1, and those of Cd were 1.5 and 0.3, respectively; while in unpolluted wetland, the concentration of Hg and Cd was 6.8 and 8.5 mg.kg(-1), the BCFs of Hg by the leaf and stem were 6.8 and 12.2, and those of Cd were 7.0 and 2.7, respectively. It was indicated that Arundo donax not only had the characters of large biomass, exuberant root, and good adaptability, but also exhibited high tolerance and concentrating capability to Cd and Hg.

Content of selected elements in Boletus badius fruiting bodies growing in extremely polluted wastes.

Science.gov (United States)

Mleczek, Mirosław; Siwulski, Marek; Mikołajczak, Patrycja; Gąsecka, Monika; Sobieralski, Krzysztof; Szymańczyk, Mateusz; Goliński, Piotr

2015-01-01

The aim of the study was to analyse levels of 17 trace elements and 5 major minerals in 11 Boletus badius fruiting bodies able to grow in extremely polluted waste (flotation tailings) and polluted soil in southern Poland. The presented data widen the limited literature data about the abilities of wild-growing mushroom species to grow on heavily contaminated substrates. Content of elements in waste, soil and mushrooms was analysed by flame atomic absorption spectrometry (FAAS) and cold vapour atomic absorption spectrometry (CVAAS - Hg). The industrial areas differed greatly as regards the content of elements in flotation tailings and soil; therefore differences in Ag, Ba, Cd, Co, Fe, Mo, Ni, Pb, Ca, K, Mg, Na and P accumulation in mushrooms were observed. The highest contents of elements in mushrooms were observed for: As, Al, Cu and Zn (86 ± 28, 549 ± 116, 341 ± 59 and 506 ± 40 mg kg(-1) dry matter, respectively). Calculated bioconcentration factor (BCF) values were higher than 1 for Al (15.1-16.9), Fe (10.6-24.4) and Hg (10.2-16.4) only. The main value of the presented results is the fact that one of the common wild-growing mushroom species was able to grow on flotation tailings containing over 22 g kg(-1) of As and, additionally, effective accumulation of other elements was observed. In view of the high content of the majority of analysed elements in fruiting bodies, edible mushrooms from such polluted areas are nonconsumable.

Novel Electrosorption-Enhanced Solid-Phase Microextraction Device for Ultrafast In Vivo Sampling of Ionized Pharmaceuticals in Fish.

Science.gov (United States)

Qiu, Junlang; Wang, Fuxin; Zhang, Tianlang; Chen, Le; Liu, Yuan; Zhu, Fang; Ouyang, Gangfeng

2018-01-02

Decreasing the tedious sample preparation duration is one of the most important concerns for the environmental analytical chemistry especially for in vivo experiments. However, due to the slow mass diffusion paths for most of the conventional methods, ultrafast in vivo sampling remains challenging. Herein, for the first time, we report an ultrafast in vivo solid-phase microextraction (SPME) device based on electrosorption enhancement and a novel custom-made CNT@PPY@pNE fiber for in vivo sampling of ionized acidic pharmaceuticals in fish. This sampling device exhibited an excellent robustness, reproducibility, matrix effect-resistant capacity, and quantitative ability. Importantly, the extraction kinetics of the targeted ionized pharmaceuticals were significantly accelerated using the device, which significantly improved the sensitivity of the SPME in vivo sampling method (limits of detection ranged from 0.12 ng·g -1 to 0.25 ng·g -1 ) and shorten the sampling time (only 1 min). The proposed approach was successfully applied to monitor the concentrations of ionized pharmaceuticals in living fish, which demonstrated that the device and fiber were suitable for ultrafast in vivo sampling and continuous monitoring. In addition, the bioconcentration factor (BCF) values of the pharmaceuticals were derived in tilapia (Oreochromis mossambicus) for the first time, based on the data of ultrafast in vivo sampling. Therefore, we developed and validated an effective and ultrafast SPME sampling device for in vivo sampling of ionized analytes in living organisms and this state-of-the-art method provides an alternative technique for future in vivo studies.

Concentration factors of radionuclides in the marine organisms

International Nuclear Information System (INIS)

1996-03-01

Parameters related to the bioconcentration of radionuclides in the marine were shown by 'Assessment and guideline to the target value of dose in the environment of the power light water reactor facilities' (Nuclear Safety Commission), but the guideline data did not contain Ru and Ce relating to the reprocessing plant. So that more new data than these of 'Technical Reports Series No. 247' (published by IAEA in 1985) were mainly collected. Especially the data of nuclides with poor data of concentration factors (CF) and natural radionuclides (Po-210, Pb-210) were gathered. These data were pigeonholed and many tables (element, kinds of organisms, experimental methods) were made by separating the general remarks from the original experimental reports. The contents of this report are given as under, history of concentration factor (CF), determination method of CF, CF calculation method, calculation models related to CF, tables of metabolic parameters, tables of CF, the present conditions of studies for uptake of radionuclides with long half-life into the marine organisms, CF abstract tables and trial calculation of human exposure by eating the marine organisms. (S.Y.)

Periodic depuration of anthracene metabolites by rainbow trout

International Nuclear Information System (INIS)

Linder, G.; Bergman, H.L.

1984-01-01

Rainbow trout Salmo gairdneri, statically exposed to 36 μg/liter anthracene (including 9- 14 C-C anthracene), bioconcentrated the polynuclear aromatic hydrocarbon 200 times the exposure concentration over 18 hours. Then, during a 96-hour clearance periods, mass-balance analysis of fish and water samples indicated that anthracene was rapidly converted to polar metabolites(s), then eliminated periodically. Maximum depuration occurred during the dark phase of a 16-hour-light: 8-hour-dark photocycle. Of the 2-3% contribution of 14 C metabolites(s) to the total 14 C residue, nearly half came from the bile. This periodic depuration may be circadian, although this requires confirmation by further work; to the extent it affects metabolic fate of bioconcentrated organics, periodic depuration undoubtedly contributes to differences between predicted and observed bioconcentration factors

浮萍生物富集洛克沙胂与阿散酸的动力学特性研究%Researches on the Kinetic Characteristics of Bioconcentration of Roxarsone and Arsanilic Acid in Duckweed (Lemna minor L.)

Institute of Scientific and Technical Information of China (English)

王付民; 张璐; 陈杖榴

2007-01-01

通过静态法和半静态法研究了浮萍Lemna minor生物富集0.1、0.5、1.0、2.0 mg·L-1洛克沙胂、阿散酸(以砷计)的动力学过程.静态法的研究结果表明:大约55 d,浮萍生物富集各个质量浓度的洛克沙胂、阿散酸均基本达到平衡;0.1、0.5、1.0、2.0 mg·L-1洛克沙胂的生物富集系数(BCF)分别为:3 116.7、1 308.0、548.4、355.0;0.1、0.5、1.0、2.0 mg·L-1阿散酸的BCF分别为:690.0、341.1、255.9、179.8;而且浮萍对各个质量浓度的洛克沙胂、阿散酸的BCF随水体浓度升高而减小.半静态法研究结果表明:浮萍对洛克沙胂、阿散酸的生物富集系数(BCF)、吸收速率常数(K1)随水体质量浓度的增大而减小;同等质量浓度的洛克沙胂的吸收速率常数(K1)大于阿散酸.

Evaluation of the assimilation of As by vegetables in contaminated soils submitted to a remediation process

Science.gov (United States)

Pérez-Sirvent, Carmen; Martinez Sanchez, Maria Jose; Agudo, Ines; Belen Martinez, Lucia; Bech, Jaume

2016-04-01

A greenhouse trial was carried out to evaluate the assimilation of heavy metals by three types of plants (lettuce, onion and broccoli), different parts of which are destined for human and farm animals consumption (leaves, roots, fruits). The experiments were carried out to check the validity of the use of calcareous materials to recover soils contaminated with heavy metals. The aim of this work was to apply a technology for decontamination to ensure that As do not enter into the trophic chain at risky levels and analyze and to assess the risk pre and post operational of the different treatments proposed. The materials used was a soils to be remediated (mining soils) and the materials used for remediation were lime filler and Construction and Demolition Waste (CDW). The plants were cultivated in greenhouse with several types of soil. Five experiments were used, namely, Tc (contaminated soil), T1 (uncontaminated soil (blank soil)), T2 (50% T1 + 50% Tc), T3 (Tc + (25%) lime residues coming from quarries) and T4 (Tc + (25%) residues coming from demolition and construction activities). The entire project involves twenty experiments which were prepared from soils highly contaminated mixed with two types of calcareous materials. The total As content of the soils samples, rhizosphere and vegetable samples, were measured and the translocation factor (TF), which is defined as the ratio of metal concentration in the leaves or shoots to the roots, and the Bioconcentration factor (BCF), which is defined as the ratio of metal concentration in the roots to that in soil were calculated. The use of CDR is shown to be a suitable way for remediating soils contaminated by metals. The methodology permits a revalorization of CDW.

Inheritance profile of weathered chlordane and p,p'-DDTs accumulation by Cucurbita pepo hybrids.

Science.gov (United States)

Isleyen, Mehmet; Sevim, Pinar; Hawthorne, Joseph; Berger, William; White, Jason C

2013-01-01

Cucurbita pepo ssp pepo (zucchini) accumulates significant levels of persistent organic pollutants in its roots, followed by unexpectedly high contaminant translocation to the stems. Most other plant species, including the closely related C. pepo ssp ovifera (squash), do not have this ability. To investigate the mechanism of contaminant accumulation, two cultivars each of parental zucchini and squash, as well as previously created first filial (F1) hybrids and F1 backcrosses (BC) of those parental cultivars, were grown under field conditions in a soil contaminated with weathered chlordane (2.29 microg/g) and DDX residues (0.30 microg/g; sum of DDT, DDE, DDD). The parental zucchini had stem-to-soil bioconcentration factors (BCF, contaminant ratio of stem to soil) for chlordane and DDX of 6.23 and 3.10; these values were 2.2 and 3.7 times greater than the squash, respectively. Chlordane and DDX translocation factors, the ratio of contaminant content in the stems to that in the root, were 2.1 and 3.2 times greater for zucchini than for squash. The parental zucchini and squash also differed significantly in chlordane component ratios (relative amounts of trans-nonachlor [TN], cis-chlordane [CC], trans-chlordane [TC]) and enantiomer fractions for the chiral CC and TC. Hybridization of the parental squash and zucchini resulted in significant differences in contaminant uptake. For both the three separate component ratios (CR) and two sets of enantiomer fraction (EF) values, subspecies specific differences in the parental generation became statistically equivalent in the F1 hybrid zucchini and squash. When backcrossed (BC) with the original parental plants, the zucchini and squash F1 BC cultivars reverted to the statistically distinct CR and EF patterns. This pattern of trait segregation upon hybridization suggests either single gene or single locus control for persistent organic pollutant (POP) uptake ability by C. pepo ssp pepo.

Cadmium tolerance and accumulation characteristics of mature flax, cv. Hermes: Contribution of the basal stem compared to the root

Energy Technology Data Exchange (ETDEWEB)

Douchiche, Olfa, E-mail: olfa.douchiche@hotmail.fr [Laboratory Glyco-MEV EA 4358, IFRMP 23, University of Rouen, 76821 Mont Saint Aignan Cedex (France); Laboratory Biologie et Physiologie Cellulaires Vegetales, Department of Biology, University of Tunis, 1060 Tunis (Tunisia); Chaiebi, Wided [Laboratory Biologie et Physiologie Cellulaires Vegetales, Department of Biology, University of Tunis, 1060 Tunis (Tunisia); Morvan, Claudine, E-mail: claudine.morvan@univ-rouen.fr [Laboratory PBS-UMR 6270 CNRS, FR 3038, University of Rouen, 76821 Mont Saint Aignan Cedex (France)

2012-10-15

Highlights: Black-Right-Pointing-Pointer Cd accumulated in stem bottom part exceeded the defined hyperaccumulator threshold. Black-Right-Pointing-Pointer No toxic symptoms occurred and TI of all growth parameters ranged between 0.7 and 1. Black-Right-Pointing-Pointer The high level of Zn, Mn and Cu may contribute to the absence of chlorosis in stem. Black-Right-Pointing-Pointer Cd/Ca synergistic effect observed in the stem may alleviate Cd toxicity. Black-Right-Pointing-Pointer Hermes variety accumulated more Cd than the other flax varieties ever described. - Abstract: The potential of mature flax plants (cv. Hermes) to tolerate and accumulate cadmium (Cd) was studied to determine which part of the plant would be the key organ for phytoremediation purposes. After 4 month-growth on sand substrate containing 0.1 mM Cd in a greenhouse, the roots and stems were separated and the stems were divided into three parts. The effects of Cd were studied on growth parameters, histology and mineral nutrition. No visible toxic symptoms were observed. Tolerance-index values calculated from growth parameters and nutrients remained relatively high, allowing the development of the plant until maturity and formation of seeds. The roots and bottom stem accumulated the highest quantity of Cd (750 and 360 mg/kg dry matter), values which largely exceeded the threshold defined for hyperaccumulators. On the other hand, basal stem had a high bioconcentration factor (BCF = 32) and translocation factor TF Prime (2.5) but a low TF (0.5), indicating that this basal part would play a major role in phytoremediation (phytostabilization rather than phytorextraction). Therefore, the high tolerance to Cd and accumulation capacity make possible to grow Hermes flax on Cd-polluted soils.

Effect of Biological Contact Filters (BCFs on Membrane Fouling in Drinking Water Treatment Systems

Directory of Open Access Journals (Sweden)

Susumu Hasegawa

2017-12-01

Full Text Available Membrane fouling is a serious problem in drinking water treatment systems. Biological contact filters (BCFs are often used as a pretreatment to remove ammonia, dissolved organic matter (DOM, and metal ions such as iron and manganese. In this study, the effect of BCF as a pretreatment for membrane fouling was evaluated using a laboratory-scale mini module consisting of a mini BCF column and a mini MF column. Initially, it was confirmed that the main foulant was a biopolymer (at low concentration in the raw water. Subsequently, the biopolymer concentrations in the BCF influent and effluent were measured with the excitation emission matrix (EEM fluorescence spectroscopy and the liquid chromatograph organic carbon detector (LC-OCD. The fouling potential of the BCF influent and effluent was also measured to evaluate MF membrane fouling rate. The results demonstrate that application of the BCF reduced the biopolymer concentration of the effluent and reduced membrane fouling. The effect of BCF was also established in an actual drinking water treatment plant. It was found that optimizing the contact time of raw water with the BCF was crucial to reduce membrane fouling.

Biotemplated preparation of CdS nanoparticles/bacterial cellulose hybrid nanofibers for photocatalysis application

International Nuclear Information System (INIS)

Yang, Jiazhi; Yu, Junwei; Fan, Jun; Sun, Dongping; Tang, Weihua; Yang, Xuejie

2011-01-01

In this work, we describe a novel facile and effective strategy to prepare micrometer-long hybrid nanofibers by deposition of CdS nanoparticles onto the substrate of hydrated bacterial cellulose nanofibers (BCF). Hexagonal phase CdS nanocrystals were achieved via a simple hydrothermal reaction between CdCl 2 and thiourea at relatively low temperature. The prepared pristine BCF and the CdS/BCF hybrid nanofibers were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-vis absorption spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results reveal that the CdS nanoparticles were homogeneously deposited on the BCF surface and stabilized via coordination effect. The CdS/BCF hybrid nanofibers demonstrated high-efficiency photocatalysis with 82% methyl orange (MO) degradation after 90 min irradiation and good recyclability. The results indicate that the CdS/BCF hybrid nanofibers are promising candidate as robust visible light responsive photocatalysts.

Biotemplated preparation of CdS nanoparticles/bacterial cellulose hybrid nanofibers for photocatalysis application.

Science.gov (United States)

Yang, Jiazhi; Yu, Junwei; Fan, Jun; Sun, Dongping; Tang, Weihua; Yang, Xuejie

2011-05-15

In this work, we describe a novel facile and effective strategy to prepare micrometer-long hybrid nanofibers by deposition of CdS nanoparticles onto the substrate of hydrated bacterial cellulose nanofibers (BCF). Hexagonal phase CdS nanocrystals were achieved via a simple hydrothermal reaction between CdCl(2) and thiourea at relatively low temperature. The prepared pristine BCF and the CdS/BCF hybrid nanofibers were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-vis absorption spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results reveal that the CdS nanoparticles were homogeneously deposited on the BCF surface and stabilized via coordination effect. The CdS/BCF hybrid nanofibers demonstrated high-efficiency photocatalysis with 82% methyl orange (MO) degradation after 90 min irradiation and good recyclability. The results indicate that the CdS/BCF hybrid nanofibers are promising candidate as robust visible light responsive photocatalysts. Copyright © 2011 Elsevier B.V. All rights reserved.

Biotemplated preparation of CdS nanoparticles/bacterial cellulose hybrid nanofibers for photocatalysis application

Energy Technology Data Exchange (ETDEWEB)

Yang, Jiazhi; Yu, Junwei [Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education), Nanjing University of Science and Technology, Nanjing 210094 (China); Fan, Jun [School of Environment, Nanjing University, Nanjing 210093 (China); Sun, Dongping [Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education), Nanjing University of Science and Technology, Nanjing 210094 (China); Tang, Weihua [Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education), Nanjing University of Science and Technology, Nanjing 210094 (China); Yang, Xuejie [Key Laboratory of Soft Chemistry and Functional Materials (Ministry of Education), Nanjing University of Science and Technology, Nanjing 210094 (China)

2011-05-15

In this work, we describe a novel facile and effective strategy to prepare micrometer-long hybrid nanofibers by deposition of CdS nanoparticles onto the substrate of hydrated bacterial cellulose nanofibers (BCF). Hexagonal phase CdS nanocrystals were achieved via a simple hydrothermal reaction between CdCl{sub 2} and thiourea at relatively low temperature. The prepared pristine BCF and the CdS/BCF hybrid nanofibers were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-vis absorption spectroscopy (UV-vis), and X-ray photoelectron spectroscopy (XPS). The results reveal that the CdS nanoparticles were homogeneously deposited on the BCF surface and stabilized via coordination effect. The CdS/BCF hybrid nanofibers demonstrated high-efficiency photocatalysis with 82% methyl orange (MO) degradation after 90 min irradiation and good recyclability. The results indicate that the CdS/BCF hybrid nanofibers are promising candidate as robust visible light responsive photocatalysts.

Determination of mineral contents of wild Boletus edulis mushroom and its edible safety assessment.

Science.gov (United States)

Su, Jiuyan; Zhang, Ji; Li, Jieqing; Li, Tao; Liu, Honggao; Wang, Yuanzhong

2018-04-06

This study aimed to determine the contents of main mineral elements of wild Boletus edulis and to assess its edible safety, which may provide scientific evidence for the utilization of this species. Fourteen mineral contents (Ba, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Na, Ni, Sr, V and Zn) in the caps and stipes of B. edulis as well as the corresponding surface soils collected from nine different geographic regions in Yunnan Province, southwest China were determined. The analyses were performed using inductively coupled plasma atomic emission spectrometer (ICP-AES) after microwave digestion. Measurement data were analyzed using variance and Pearson correlation analysis. Edible safety was evaluated according to the provisionally tolerable weekly intake (PTWI) of heavy metals recommended by United Nations Food and Agriculture Organization and World Health Organization (FAO/WHO). Mineral contents were significantly different with the variance of collection areas. B. edulis showed relative abundant contents of Ca, Fe, Mg and Na, followed by Ba, Cr, Cu, Mn and Zn, and the elements with the lower content less were Cd, Co, Ni, Sr and V. The elements accumulation differed significantly in caps and stipes. Among them, Cd and Zn were bioconcentrated (BCF > 1) while others were bioexcluded (BCF < 1). The mineral contents in B. edulis and its surface soil were positively related, indicating that the elements accumulation level was related to soil background. In addition, from the perspective of food safety, if an adult (60 kg) eats 300 g fresh B. edulis per week, the intake of Cd in most of tested mushrooms were lower than PTWI value whereas the Cd intakes in some other samples were higher than this standard. The results indicated that the main mineral contents in B. edulis were significantly different with respect to geographical distribution, and the Cd intake in a few of regions was higher than the acceptable intakes with a potential risk.

Tissue uptake, distribution and elimination of {sup 14}C-PFOA in zebrafish (Danio rerio)

Energy Technology Data Exchange (ETDEWEB)

Ulhaq, Mazhar [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Sundström, Maria [Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm (Sweden); Larsson, Pia; Gabrielsson, Johan [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Bergman, Åke [Environmental Chemistry Unit, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm (Sweden); Norrgren, Leif [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden); Örn, Stefan, E-mail: Stefan.Orn@slu.se [Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-750 07 Uppsala (Sweden)

2015-06-15

Highlights: • Bioconcentration of PFOA at steady-state was approximately 20–30 times. • High concentrations were observed in bile and intestines implying enterohepatic circulation. • PFOA accumulated in oocytes indicating maternal transfer. - Abstract: Perfluorooctanoic acid (PFOA) is a long-chain perfluorinated chemical that has been shown to be non-degradable and persistent in the environment. Laboratory studies on bioconcentration and compound-specific tissue distribution in fish can be valuable for prediction of the persistence and environmental effects of the chemicals. In the present study male and female zebrafish (Danio rerio) were continuously exposed to 10 μg/L of radiolabeled perfluorooctanoic acid ({sup 14}C-PFOA) for 40 days, after which the exposed fish were transferred to fresh clean water for another 80 days wash-out period. At defined periodic intervals during the uptake and wash-out, fish were sampled for liquid scintillation counting and whole body autoradiography to profile the bioconcentration and tissue distribution of PFOA. The steady-state concentration of {sup 14}C-PFOA in the zebrafish was reached within 20–30 days of exposure. The concentration-time course of {sup 14}C-PFOA displayed a bi-exponential decline during washout, with a terminal half-life of approximately 13–14 days. At steady-state the bioconcentration of {sup 14}C-PFOA into whole-body fish was approximately 20–30 times greater than that of the exposure concentration, with no differences between females and males. The bioconcentration factors for liver and intestine were approximately 100-fold of the exposure medium, while in brain, ovary and gall bladder the accumulation factors were in the range 15–20. Whole-body autoradiograms confirmed the highest labeling of PFOA in bile and intestines, which implies enterohepatic circulation of PFOA. The {sup 14}C-PFOA was also observed in maturing vitellogenic oocytes, suggesting chemical accumulation via yolk proteins

The effect of technogenic emissions on the heavy metals accumulation by herbaceous plants.

Science.gov (United States)

Chaplygin, Victor; Minkina, Tatiana; Mandzhieva, Saglara; Burachevskaya, Marina; Sushkova, Svetlana; Poluektov, Evgeniy; Antonenko, Elena; Kumacheva, Valentina

2018-02-07

The effect of technogenic emissions on the input of Pb, Zn, Cd, Cu, Mn, Cr, and Ni into plants from the Poaceae and Asteraceae families has been studied. Soil and plant contamination by anthropogenic emissions from industrial enterprises leads the decreasing of crop quality; therefore, the monitoring investigation of plants and soils acquires special importance. The herbaceous plants may be used as bioindicators for main environmental changes. It was found that the high level of anthropogenic load related to atmospheric emissions from the power plant favors the heavy metal (HM) accumulation in herbaceous plants. Contamination with Pb, Cd, Cr, and Ni was revealed in plants growing near the power plant. Heavy metals arrive to plants from the soil in the form of mobile compounds. Plant family is one of the main factors affecting the HM distribution in the above- and underground parts of plants. Plants from the Poaceae family accumulate less chemical elements in their aboveground parts than the Asteraceae plants. Ambrosia artemisiifolia and Artemisia austriaca are HM accumulators. For assessing the stability of plants under contamination with HMs, metal accumulation by plants from soil (the bioconcentration factor) and metal phytoavailability from plants above- and underground parts (the acropetal coefficient) were calculated. According to the bioconcentration factor and translocation factor values, Poaceae species are most resistant to technogenic contamination with HMs. The translocation factor highest values were found for Tanacetum vulgare; the lowest bioconcentration factor values were typical for Poa pratensis.

Uptake of phosphorus from feed by carps

International Nuclear Information System (INIS)

Kellermann, H.J.; Buehringer, H.

1993-01-01

One of the aims of the International Conference for the Protection of the North Sea is to reduce the input of nutrients by 50% within the period of 1985 -1995. This is only possible by reducing the riverine input of phosphorus into the North Sea. For the regulated shortlived isotope of this element the bioconcentration factor to fishmeat is determined by the phosporus concentration in the water on the one hand and by the biological turn over rate in tissue on the other hand. Aquaria studies of the turn over rate of carps at different feed applications reveal that the recommended bioconcentration factor does not yield the desired conservative assessment. (orig.) [de

Radioecological studies in marine ecosystems

International Nuclear Information System (INIS)

Kellermann, H.J.; Kanisch, G.

1999-01-01

The bioconcentration factor shows the ratio between concentration of a substance in water or in fish. It is a calculation quantity, used for assessing the possible concentration in fish in proportion to the known concentration in water. Although the element cesium discussed in this report is primarily ingested via the food chain (biomagnification) and not via direct uptake through the gills, but the bioconcentration factor model is nevertheless applicable, because there is a relation between the element's concentration in water and in food. One has to consider, however, the influence on cesium uptake through the quantity of food and species-dependent accumulation. Experimental results obtained for various ecosystems are reported and illustrate the mechanisms involved. (orig./CB) [de

Bioconcentration of artificial radionuclides in edible mushrooms: in situ and in vitro studies

Energy Technology Data Exchange (ETDEWEB)

Dementyev, Dmitry V.; Manukovsky, Nikolai S.; Bolsunovsky, Alexander Ya.; Alexandrova, Yuliyana V. [Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, 660036, Krasnoyarsk (Russian Federation)

2014-07-01

Some areas of the Yenisei River basin are affected by the operation of the Mining-and-Chemical Combine (MCC), producing weapons-grade plutonium. Flood plain soils of the Yenisei contain a wide range of artificial radionuclides, including transuranium elements, which can be accumulated by living organisms. Concentrations of artificial radionuclides and heavy metals accumulated by mushrooms may be several orders of magnitude higher than those accumulated by plants, and, thus, mushrooms may be used as bio-concentrators of radionuclides and heavy metals for bioremediation of contaminated areas. The purposes of this study were to investigate 1) species specificity of accumulation of artificial radionuclides by edible mushrooms in radioactively contaminated areas of the Yenisei River flood plain and 2) accumulation rates of artificial radionuclides, including transuranium elements, in mushrooms under laboratory conditions. Species specificity of accumulation of artificial radionuclides and uranium by mushrooms was analyzed for 12 species of edible mushrooms. The study was performed at the sites affected by MCC operation, which were divided into two groups: 1) the sites only affected by aerosol-bound radionuclides and 2) the sites that also received waterborne radionuclides. Field studies showed great interspecific variations in Cs-137 accumulation by mushrooms. Activity concentrations of Cs-137 in bioindicator species Suillus granulatus and S. Luteus reached 10 kBq/kg dry weight. S. granulatus and S. luteus are concentrators of Cs-137, as suggested by the analysis of concentration factors (CFs), which reached 0.7-16 for these mushroom species. The CF of U-238 in fruiting bodies of the mushrooms was no greater than 0.11. Yenisei flood plain soils contain a wide range of transuranium elements, which can accumulate in environmental objects. Laboratory experiments on accumulation of Am-241 from solution by mycelium and Am-241 accumulation by fruiting bodies of mushrooms

Bioaccumulation of 137Cs by microorganisms isolated from soils contaminated with radionuclides

International Nuclear Information System (INIS)

Pipiska, M.; Hornik, M.; Augustin, J.

2003-01-01

With the aim to evaluate the possibility of utilisation of autochtone population of soil organisms, alone or with participation of higher plants, in the processes of bioremediation the authors quantitatively determined a number of psychrophyllic and mezophyllic germs in the soils contaminated by low-level activities of Cs-137 (0.08 - 2.8 kBq/g). Hereafter they gained isolates of clean cultures of mushrooms and actinomycetes and they determined their bioacumulative activity of Cs-137 at growing conditions. The authors found out, that a number of reproductionable psychrophyllic and mezophyllic germs are significantly lower in the soils with the highest contamination by radionuclides than in the soils with low contamination. They gained the clean cultures of 5 isolates of micromycetes and 3 isolates of actinomycetes from contaminated soil. The micromycetes demonstrated the highest values of bioaccumulation of caesium 39 nmol/g of wet biomass at the growing conditions. In actionoomycetes these values were 4.7 nmol/g (approximately in one order lower). The significant part of cesium accumulated by cell matter at growing conditions were localised in cell matter and it could not be removed by washing with 0.9 percent of NaCl solution. The determined values of bioconcentration factor BCF recalculated on dry weight of biomass were in the range from 16.04 to 26.20 in micromycetes and 3.24 in actinomycetes. From this situation arise, that autochtone population of soil micromycetes and actionomycetes, which is found in contaminated soil, can relevantly participate in the processes of binding of biologically accessible forms of Cs-137 after a creation of suitable conditions for grow. (author)

Total mercury and methylmercury accumulation in wild plants grown at wastelands composed of mine tailings: Insights into potential candidates for phytoremediation.

Science.gov (United States)

Qian, Xiaoli; Wu, Yonggui; Zhou, Hongyun; Xu, Xiaohang; Xu, Zhidong; Shang, Lihai; Qiu, Guangle

2018-08-01

Total mercury (THg) and methylmercury (MMHg) were investigated in 259 wild plants belonging to 49 species in 29 families that grew in heavily Hg-contaminated wastelands composed of cinnabar ore mine tailings (calcines) in the Wanshan region, southwestern China, the world's third largest Hg mining district. The bioconcentration factors (BCFs) of THg and MMHg from soil to roots ([THg] root /[THg] soil , [MMHg] root /[MMHg] soil ) were evaluated. The results showed that THg and MMHg in both plants and soils varied widely, with ranges of 0.076-140 μg/g THg and 0.19-87 ng/g MMHg in roots, 0.19-106 μg/g THg and 0.06-31 ng/g MMHg in shoots, and 0.74-1440 μg/g THg and 0.41-820 ng/g MMHg in soil. Among all investigated species, Arthraxon hispidus, Eremochloa ciliaris, Clerodendrum bunge, and Ixeris sonchifolia had significantly elevated concentrations of THg in shoots and/or roots that reached 100 μg/g, whereas Chenopodium glaucum, Corydalisedulis maxim, and Rumex acetosa contained low values below 0.5 μg/g. In addition to the high THg concentrations, the fern E. ciliaris also showed high BCF values for both THg and MMHg exceeding 1.0, suggesting its capability to extract Hg from soils. Considering its dominance and the tolerance identified in the present study, E. ciliaris is suggested to be a practical candidate for phytoextraction, whereas A. hispidus is identified as a potential candidate for phytostabilization of Hg mining-contaminated soils. Copyright © 2018 Elsevier Ltd. All rights reserved.

Quantification of inorganic arsenic exposure and cancer risk via consumption of vegetables in southern selected districts of Pakistan

Science.gov (United States)

Rehman, Zahir Ur; Khan, Sardar; Qin, Kun; Brusseau, Mark L; Shah, Mohammad Tahir; Din, Islamud

2016-01-01

Human exposures to arsenic (As) through different pathways (dietary and non-dietary) are considered to be one of the primary worldwide environmental health risks to humans. This study was conducted to investigate the presence of As in soil and vegetable samples collected from agricultural lands located in selected southern districts of Khyber Pakhtunkhwa (KPK) Province, Pakistan. We examined the concentrations of total arsenic (TAs), organic species of As such as monomethylarsonic acid (MMA) and dimethylarsonic acid (DMA), and inorganic species including arsenite (AsIII) and arsenate (AsV) in both soil and vegetable. The data were used to determine several parameters to evaluate human health risk, including bioconcentration factor (BCF) from soil to plant, average daily intake (ADI), health risk index (HRI), incremental lifetime cancer risk (ILTCR), and hazard quotient (HQ). The total As concentration in soil samples of the five districts ranged from 3.0-3.9 mg kg−1, exhibiting minimal variations from site to site. The mean As concentration in edible portions of vegetable samples ranged from 0.03-1.38 mg kg−1. It was observed that As concentrations in 75% of the vegetable samples exceeded the safe maximum allowable limit (0.1 mg kg−1) set by WHO/FAO. The highest value of ADI for As was measured for M. charantia, while the lowest was for A. chinense. The results of this study revealed minimal health risk (HI vegetables for the local inhabitants. The ILTCR values for inorganic As indicated a minimal potential cancer risk through ingestion of vegetables. In addition, the HQ values for total As were <1, indicating minimal non-cancer risk. PMID:26820935

Inheritance of p,p'-DDE phytoextraction ability in hybridized Cucurbita pepo cultivars.

Science.gov (United States)

White, Jason C

2010-07-01

Cucurbita pepo ssp pepo (zucchini) has been shown to uniquely phytoextract percent level amounts of dichlorodiphenyldichloroethylene (DDE) and other organic contaminants from soil. Since C. pepo ssp ovifera (squash) does not have this ability, a three-year field trial was conducted to follow the inheritance pattern of DDE accumulation for cross pollinated C. pepo cultivars. Parental zucchini and squash cultivars (3 each) had stem-to-soil bioconcentration factors (BCF, contaminant ratio of stem to soil) of 16 and 1.7, respectively, and phytoextracted 1.8 and 0.18% of the DDE from soil. The 18 possible first filial (F1) hybrids of zucchini and squash accumulated significantly different DDE levels than the respective parents. The zucchini F1 hybrid (zucchini pollinated with squash) stem BCFs and percent phytoextraction values were 10 and 0.96, respectively, or 36% and 47% less than the parental zucchini. The squash F1 hybrid (squash pollinated with zucchini) stem BCFs and percent phytoextraction values were 8.3 and 0.68, respectively, or 490% and 370% greater than the parental squash. When backcrossed (BC) with the original parent, the nine zucchini F1 BC cultivars did not regain the capability to take up DDE; stem BCFs and percent phytoextraction values were equivalent to those of the F1 generation. However, the nine squash F1 BC cultivars lost much of the DDE uptake capability of the F1 generation; stem BCFs and percent phytoextraction values were intermediate but closer to those of the parental squash. The inheritance patterns suggest single locus control for persistent organic pollutant (POP) uptake ability in C. pepo ssp pepo.

Sublethal toxicity and biotransformation of pyrene in Lumbriculus variegatus (Oligochaeta)

International Nuclear Information System (INIS)

Maeenpaeae, K.; Leppaenen, M.T.; Kukkonen, J.V.K.

2009-01-01

The aim of this work was to study the toxicity and biotransformation of polyaromatic hydrocarbon (PAH) pyrene in the oligochaete aquatic worm, Lumbriculus variegatus. PAHs are ubiquitous environmental pollutants that pose a hazard to aquatic organisms, and metabolizing capability is poorly known in the case of many invertebrate species. To study the toxicity and biotransformation of pyrene, the worm was exposed for 15 days to various concentrations of water-borne pyrene. The dorsal blood vessel pulse rate was used as a sublethal endpoint. Pyrene biotransformation by L. variegatus was studied and the critical body residues (CBR) were estimated for pyrene toxicity. The toxicokinetics of pyrene uptake was evaluated. A combination of radiolabeled ( 14 C) and nonlabeled pyrene was used in the exposures, and liquid scintillation counting (LSC) and high-pressure liquid chromatography were employed in both water and tissue residue analyses. The results showed that L. variegatus was moderately able to metabolize pyrene to 1-hydroxypyrene (1-HP), thus demonstrating that the phase-I-like oxidizing enzyme system metabolizes pyrene in L. variegatus. The amount of the 1-HP was 1-2% of the amount of pyrene in the worm tissues. The exposure to pyrene reduced the blood vessel pulse rate significantly (p < 0.05), showing that pyrene had a narcotic effect. The estimated CBRs remained constant during the exposure time, varying from 0.120 to 0.174 mmol pyrene/kg worm wet weight. The bioconcentration factors (BCF) decreased as exposure concentration increased. It was suggested that the increased toxicity of pyrene accounted for the decrease in BCFs by lowering the activity of the organism

Arbuscular mycorrhizae alleviate negative effects of zinc oxide nanoparticle and zinc accumulation in maize plants--A soil microcosm experiment.

Science.gov (United States)

Wang, Fayuan; Liu, Xueqin; Shi, Zhaoyong; Tong, Ruijian; Adams, Catharine A; Shi, Xiaojun

2016-03-01

ZnO nanoparticles (NPs) are considered an emerging contaminant when in high concentration, and their effects on crops and soil microorganisms pose new concerns and challenges. Arbuscular mycorrhizal (AM) fungi (AMF) form mutualistic symbioses with most vascular plants, and putatively contribute to reducing nanotoxicity in plants. Here, we studied the interactions between ZnO NPs and maize plants inoculated with or without AMF in ZnO NPs-spiked soil. ZnO NPs had no significant adverse effects at 400 mg/kg, but inhibited both maize growth and AM colonization at concentrations at and above 800 mg/kg. Sufficient addition of ZnO NPs decreased plant mineral nutrient acquisition, photosynthetic pigment concentrations, and root activity. Furthermore, ZnO NPs caused Zn concentrations in plants to increase in a dose-dependent pattern. As the ZnO NPs dose increased, we also found a positive correlation with soil diethylenetriaminepentaacetic acid (DTPA)-extractable Zn. However, AM inoculation significantly alleviated the negative effects induced by ZnO NPs: inoculated-plants experienced increased growth, nutrient uptake, photosynthetic pigment content, and SOD activity in leaves. Mycorrhizal plants also exhibited decreased ROS accumulation, Zn concentrations and bioconcentration factor (BCF), and lower soil DTPA-extractable Zn concentrations at high ZnO NPs doses. Our results demonstrate that, at high contamination levels, ZnO NPs cause toxicity to AM symbiosis, but AMF help alleviate ZnO NPs-induced phytotoxicity by decreasing Zn bioavailability and accumulation, Zn partitioning to shoots, and ROS production, and by increasing mineral nutrients and antioxidant capacity. AMF may play beneficial roles in alleviating the negative effects and environmental risks posed by ZnO NPs in agroecosystems. Copyright © 2015 Elsevier Ltd. All rights reserved.

Macronutrients and trace metals in soil and food crops of Isfahan Province, Iran.

Science.gov (United States)

Keshavarzi, Behnam; Moore, Farid; Ansari, Maryam; Rastegari Mehr, Meisam; Kaabi, Helena; Kermani, Maryam

2015-01-01

The distribution of 10 macronutrients and trace metals in the arable soils of Isfahan Province, their phytoavailability, and associated health risks were investigated; 134 plant and 114 soil samples (from 114 crop fields) were collected and analyzed at harvesting time. Calculation of the soil pollution index (SPI) revealed that arable soil polluted by metals was more severe in the north and southwest of the study area. The results of cluster analysis indicated that Pb, Zn, and Cu share a similar origin from industries and traffic. The concentrations of macronutrients and trace metals in the sampled crops were found in the order of K > Ca > S > Mg > P and Fe > Mn > Zn > Cu > Pb, respectively, whereas calculation of the bioconcentration factor (BCF) indicated that the accumulation of the investigated elements in crops was generally in the order of S ≈ K > P > Mg > Ca and Zn > Cu > Mn > Pb > Fe, respectively. Thus, various parameters including crop species and the physical, chemical, and biological properties of soil also affected the bioavailability of the elements besides the total element contents in soil. Daily intake (DI) values of elements were lower than the recommended daily intake (RDI) levels in rice grains except for Fe and Mn, but for wheat grains, all elements displayed DI values higher than the RDI. Moreover, based on the hazard index (HI) values, inhabitants are experiencing a significant potential health risk solely due to the consumption of wheat and rice grains (particularly wheat grains). Mn health quotient (HQ) also indicated a high risk of Mn absorption for crop consumer inhabitants.

Accumulation factors of mercury by King Bolete Boletus edulis

Science.gov (United States)

Falandysz, J.; Frankowska, A.

2003-05-01

To understand pollution picture with mercury and to examine suitability of King Bolete Boletits edulis Bull.: Fr. as possible bioindicator the total mercurv concentrations were determined both in the fruiting bodies and underlying soil substrate collected from various regions of Poland. There were quite large spatial variations of mercury concentration and some seasonal also were noted. Mercury content of the caps exceeded that of stalks (p<0.05), Nvhile Hg BCF values varied between 9 and 40, and 4 and 40, respectively.

From atoms to steps: The microscopic origins of crystal evolution

Science.gov (United States)

Patrone, Paul N.; Einstein, T. L.; Margetis, Dionisios

2014-07-01

The Burton-Cabrera-Frank (BCF) theory of crystal growth has been successful in describing a wide range of phenomena in surface physics. Typical crystal surfaces are slightly misoriented with respect to a facet plane; thus, the BCF theory views such systems as composed of staircase-like structures of steps separating terraces. Adsorbed atoms (adatoms), which are represented by a continuous density, diffuse on terraces, and steps move by absorbing or emitting these adatoms. Here we shed light on the microscopic origins of the BCF theory by deriving a simple, one-dimensional (1D) version of the theory from an atomistic, kinetic restricted solid-on-solid (KRSOS) model without external material deposition. We define the time-dependent adatom density and step position as appropriate ensemble averages in the KRSOS model, thereby exposing the non-equilibrium statistical mechanics origins of the BCF theory. Our analysis reveals that the BCF theory is valid in a low adatom-density regime, much in the same way that an ideal gas approximation applies to dilute gasses. We find conditions under which the surface remains in a low-density regime and discuss the microscopic origin of corrections to the BCF model.

Improved Performance and Reproducibility of Perovskite Solar Cells by Well-Soluble Tris(pentafluorophenyl)borane as a p-Type Dopant.

Science.gov (United States)

Ye, Tengling; Wang, Junhai; Chen, Wenbo; Yang, Yulin; He, Dongqing

2017-05-31

In this work, well-soluble tris(pentafluorophenyl)borane (BCF) is introduced for the first time into 2,2',7,7'-tetrakis(N,N'-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) as a p-dopant. The conductivity of spiro-OMeTAD films is dramatically enhanced. When the BCF-doped spiro-OMeTAD film is used as a hole-transport layer (HTL) in perovskite solar cells (PSCs), nearly double increase in power conversion efficiency (PCE) is obtained compared to that of the PSCs based on a pristine spiro-OMeTAD HTL. By the introduction of lithium bis(trifluoromethanesulfonyl)imide and 4-tert-butylpyridine into the BCF-doped spiro-OMeTAD film, the conductivity of spiro-OMeTAD film can be further enhanced, and an optimum PCE of 14.65% is obtained. In addition, the average efficiency of the device and the reproducibility of BCF-based PSCs are better than those of FK209-based PSCs. The working mechanism of the BCF doping effect on spiro-OMeTAD is studied in detail. The strong electron-accepting ability, excellent solubility in common organic solvents, and the low cost make BCF a very attractive p-type dopant for spiro-OMeTAD.

Bio-accumulation kinetics of radioruthenium in marine bivalves. Laboratory study

International Nuclear Information System (INIS)

Mu, D.H.; Yan, S.P.; Gu, Y.J.; Li, D.J.; Du, J.Z.

2007-01-01

Three kinds of marine bivalves (wild Saccostrea cucullata, aquacultured Perna viridis and aquacultured Pinctada martens), collected from Daya Bay, the South China Sea, were used to investigate the bio-accumulation of radioruthenium in the glass aquarium with natural seawater (pH 8.20, 35 per mille salinity, filtered by 0.45 μm) at ambient temperature under laboratory feeding conditions. The experimental results show that the stead-state of biology concentration factor (BCF, ml/g) of radioruthenium was approached around 6 days for most species of bivalves. The values of BCF in shells are the highest in organs all the three bivalves. The orders of BCF values (ml x g -1 ) are as: Perna viridis (33.2) < Saccostrea cucullata (47.0) < Pinctada martensi (208.4) for shells and Saccostrea cucullata (1.5) < Pinctada martensi (2.2) ∼ Perma viridis (2.4) for soft tissues, respectively, after exposed for 14 days. The rate constants of uptake and elimination of radioruthenium on marine bivalves were also discussed by first-order kinetics model. The Pinctada martensi may be applicable to be an indictor for monitoring radioruthenium among the three bivalves. (author)

The pH dependent toxicity and bioaccumulation of chloroquine tested on S. viminalis (basket willow)

DEFF Research Database (Denmark)

Rendal, Cecilie; Trapp, Stefan; Legind, Charlotte Nielsen

2010-01-01

(hydroxymethyl) – aminomethane (pH 8 and 9). Concentrations were determined with spectrophotometer. Toxicity was derived from calculations of normalized transpiration over time, and RCF (root concentration factor) values were calculated. Increasing BCF values were found for increasing pH levels, and the toxicity...

Fate and effect of hexabromocyclododecane in the environment

Energy Technology Data Exchange (ETDEWEB)

Hunziker, R.W.; Friederich, U. [Dow Europe, GmbH, Horgen (Switzerland); MacGregor, J.A.; Desjardins, D. [Wildlife International, Ltd., Easton, MD (United States); Ariano, J. [Great Lakes Chemical Corp., West Lafayette, IN (United States); Gonsior, S.

2004-09-15

Hexabromocyclododecane (HBCD) is used as a flame retardant mainly in building insulation composed of extruded or expanded polystyrene foam. A minor use is in flame retardant back-coats of some upholstery textiles. Sales in Europe are estimated to be 9000 t/yr. HBCD has been detected in a number of environmental samples mainly in sediment of urban areas. In a series of acute aquatic toxicity tests, no effect was exhibited at concentrations equal to or below the water solubility of the technical product which consists of ca. 85% {gamma} diastereomer. However, considerable bioconcentration has been reported (log BCF=4). In recent work it has been reported that a shift occurs along the food chain, from {gamma}, the predominant isomer in the technical product, to the {alpha} isomer. HBCD is very hydrophobic and not readily biodegradable, and has been presumed to be persistent in the environment. It is therefore important to have a good understanding of the environmental fate and lifetime of all HBCD isomers. This paper describes new findings on the water solubility of HBCD with respect to its 3 individual isomers, presents results on the acute toxicity in the marine alga Skeletonema costatum at the limit of solubility of all individual isomers and shows first data of an ongoing fate study with {sup 14}C-HBCD where the primary biodegradation of the individual metabolites is differentiated.

Clams sensitivity towards As and Hg: A comprehensive assessment of native and exotic species.

Science.gov (United States)

Velez, Cátia; Freitas, Rosa; Antunes, Sara C; Soares, Amadeu M V M; Figueira, Etelvina

2016-03-01

To assess the environmental impact of As and Hg, bioindicator organisms such as bivalves have been used. Nevertheless, few studies have assessed the impacts of As and Hg in Ruditapes decussatus and Ruditapes philippinarum, which are native and exotic species in Europe, respectively. The main goal of the present study was to assess elements' partitioning and detoxification strategies of R. decussatus and R. philippinarum. Both clams showed a higher capacity to bioconcentrate Hg (BCF 2.29-7.49), when compared to As (0.59-1.09). Furthermore, As accumulation in both species was similar in the soluble and insoluble fractions, while in both species the majority of Hg was found in the insoluble fraction. Clams exposed to As showed different detoxification strategies, since R. decussatus had higher ability to enhance antioxidant enzymes and metallothioneins in order to reduce toxicity, and R.philippinarum increased glutathione S-transferase Ω activity, that catalyzes monomethyl arsenate reduction, the rate-limiting reaction in arsenic biotransformation. When exposed to Hg, R. decussatus presented, higher synthesis of antioxidant enzymes and lower LPO, being able to better tolerate Hg than the exotic species R. philippinarum. Thus under relevant levels of As and Hg contamination our work evidenced the higher ability of R. decussatus to survive and inhabit coastal environments not heavily contaminated by Hg and As. Copyright © 2015 Elsevier Inc. All rights reserved.

Multi-Scenario Use Case based Demonstration of Buildings Cybersecurity Framework Webtool

Energy Technology Data Exchange (ETDEWEB)

Gourisetti, Sri Nikhil G.; Mylrea, Michael E.; Gervais, Easton L.; Bhadra, Sraddhanjoli

2017-11-27

The purpose of this paper is to demonstrate the cybersecurity and software capabilities of Buildings Cybersecurity Framework (BCF) webtool. The webtool is designed based on BCF document and existing NIST standards. It’s capabilities and features are depicted through a building usecase with four different investment scenarios geared towards improving the cybersecurity posture of the building. BCF webtool also facilitates implementation of the goals outlined in Presidential Executive Order (EO) on Strengthening the Cybersecurity of Federal Networks and Critical Infrastructure (May 2017. In realization of the EO goals, BCF includes five core elements: Identify, Protect, Detect, Respond, and Recover, to help determine various policy and process level vulnerabilities and provide mitigation strategies. With the BCF webtool, an organization can perform a cybersecurity self-assessment; determine the current cybersecurity posture; define investment based goals to achieve a target state; connect the cybersecurity posture with business processes, functions, and continuity; and finally, develop plans to answer critical organizational cybersecurity questions. In this paper, the webtool and its core capabilities are depicted by performing an extensive comparative assessment over four different scenarios.

Flavonoid biosynthesis controls fiber color in naturally colored cotton

Directory of Open Access Journals (Sweden)

Hai-Feng Liu

2018-04-01

Full Text Available The existence of only natural brown and green cotton fibers (BCF and GCF, respectively, as well as poor fiber quality, limits the use of naturally colored cotton (Gossypium hirsutum L.. A better understanding of fiber pigment regulation is needed to surmount these obstacles. In this work, transcriptome analysis and quantitative reverse transcription PCR revealed that 13 and 9 phenylpropanoid (metabolic pathway genes were enriched during pigment synthesis, while the differential expression of phenylpropanoid (metabolic and flavonoid metabolic pathway genes occurred among BCF, GCF, and white cotton fibers (WCF. Silencing the chalcone flavanone isomerase gene in a BCF line resulted in three fiber phenotypes among offspring of the RNAi lines: BCF, almost WCF, and GCF. The lines with almost WCF suppressed chalcone flavanone isomerase, while the lines with GCF highly expressed the glucosyl transferase (3GT gene. Overexpression of the Gh3GT or Arabidopsis thaliana 3GT gene in BCF lines resulted in GCF. Additionally, the phenylpropanoid and flavonoid metabolites of BCF and GCF were significantly higher than those of WCF as assessed by a metabolomics analysis. Thus, the flavonoid biosynthetic pathway controls both brown and green pigmentation processes. Like natural colored fibers, the transgenic colored fibers were weaker and shorter than WCF. This study shows the potential of flavonoid pathway modifications to alter cotton fibers’ color and quality.

Transfer of heavy metals to biota after remediation of contaminated soils with calcareous residues.

Science.gov (United States)

Pérez-Sirvent, Carmen; Martínez-Sánchez, Maria Jose; Agudo, Ines; Gonzalez, Eva; Perez-Espinosa, Victor; Belen Martínez, Lucia; Hernández, Carmen; García-Fernandez, Antonio Juan; Bech, Jaime

2013-04-01

A study was carried out to evaluate the assimilation of heavy metals by three types of horticultural plants (broccoli, lettuce and leek), different parts of which are destined for human and farm animals consumption (leaves, roots, fruits). Five consecutive crops of each vegetable were obtained in greenhouse. In a second stage, experiments were carried out with rabbits fed with such vegetables. The plants were cultivated in four types of soil. The first one was contaminated by heavy metals (S1), the second was a uncontaminated soil (blank soil) (S2), the third was the material obtained by mixing S1 with residues coming from demolition and construction activities (S3); while the fourth was the result of remediating S1 with lime residues coming from quarries (S4). The total metal content (As, Pb, Cd and Zn) of the soil samples, rizosphere, leached water and vegetable samples, were measured, and both the translocation and bioconcentration factors (TF and BCF, respectively) were calculated. In the second stage, the effect caused in rabbits fed with the vegetables was monitorized using both external observation and the analysis of blood, urine, and the levels of metals in muscles, liver and kidney. The statistical analysis of the results obtained showed that there were no significant differences in the heavy metal levels for the vegetables cultivated in S2, S3 and S4. The results for soil sample S1 did not have a normal distribution since the growing of the vegetables were not homogeneous and also strongly dependent on the type of vegetal. As regards the effect caused in rabbits, significant differences were observed for the animals fed with plants cultivated in S1 compared with the others.

17β-estradiol as precursors of Cl/Br-DBPs in the disinfection process of different water samples.

Science.gov (United States)

Shao, Yanan; Pan, Zihan; Rong, Chuan; Wang, Yinghui; Zhu, Hongxiang; Zhang, Yuanyuan; Yu, Kefu

2018-05-21

During chlorine disinfection process, reactions between the disinfectant and 17β-estradiol (E2) lead to the formation of halogenated disinfection byproducts (DBPs) which can be a risk to both ecosystem and human health. The degradation and transformation products of E2 in sodium hypochlorite (NaClO) disinfection processes of different water samples were investigated. The reaction kinetics research showed that the degradation rates of E2 were considerably dependent on the initial pH value and the types of water samples. In fresh water, synthetic marine aquaculture water and seawater, the reaction rate constant was 0.133 min -1 , 2.067 min -1 and 2.592 min -1 , respectively. The reasons for the above phenomena may be due to the different concentrations of bromide ions (Br - ) in these three water samples which could promote the reaction between NaClO and E2. Furthermore, Br - could also cause the formation of brominated DBPs (Br-DBPs). The main DBPs, reaction centers and conceivable reaction pathways were explored. Seven halogenated DBPs have been observed including three chlorinated DBPs (Cl-DBPs) and four Br-DBPs. The active sites of E2 were found to be the pentabasic cyclic ring and the ortho position of the phenol moiety as well as C9-C10 position. The identified Cl/Br-DBPs were also confirmed in actual marine aquaculture water from a shrimp pond. The comparison of bio-concentration factors (BCF) values based on calculation of EPI-suite showed that the toxicities of the Br-DBPs were stronger than that of their chloride analogues. The absorbable organic halogens (AOX) analysis also suggested that the DBPs produced in the marine aquaculture water were more toxic than that in the fresh water system. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of pH, temperature, and lead concentration on the bioremoval of lead from water using Lemna minor.

Science.gov (United States)

Uysal, Yağmur; Taner, Fadime

2009-09-01

This study examined the ability of the aquatic plant Lemna minor (duckweed) to remove soluble lead under various laboratory conditions. In a batch process L. minor was exposed to different pH values (4.5-8.0) and temperature (15-35 degrees C) in presence of different lead concentrations (0.1-10.0 mg L(-1)) for 168 h. The amount of biomass obtained in the study period on a dry weight basis, the concentrations of lead in tissue and in medium and net uptake of lead by Lemna all have been determined in each condition. The percentages of lead uptake ratios (PMU) and bioconcentration factors (BCF) were also calculated for these conditions. Bioaccumulated lead concentrations and the PMU were obtained at lowest pH of 4.5, and at 30 degrees C. The highest accumulated lead concentration was found at pH 4.5 as 3.599 mg Pb g(-1) in 10.0 mg L(-1). It decreased to pH 6.0, but it did not change at pH 6.0-8.0 range. The maximum lead accumulation was obtained at 30 degrees C as 8.622 mg Pb g(-1) in 10 mg L(-1) at pH 5.0, and the minimum was at 15 degrees C as 0.291 mg g(-1) in 0.1 mg L(-1). Lead accumulation gradually increased with increasing lead in medium, but the opposite trend was observed for PMU. Lead accumulation increased up to 50 mg L(-1), but did not change significantly in the 50.0-100.0 mg L(-1) range. The lead uptake from water was modeled and the equation fit the experimental data very well

Evaluation of the grass mixture (Faestuca Rubra, Cynodon Dactylon, Lolium Multiflorum and Pennisetum sp.) as Sb phyto-stabilizer in tailings and Sb-rich soils.

Science.gov (United States)

Aurora Armienta, M.; Beltrán-Villavicencio, Margarita; Ruiz-Villalobos, Carlos E.; Labastida, Israel; Ceniceros, Nora; Cruz, Olivia; Aguayo, Alejandra

2017-04-01

Green house experiments were carried out to evaluate the growth and Sb assimilation of a grass assemblage: Faestuca Rubra, Cynodon Dactylon, Lolium Multiflorum and Pennisetum sp, in tailings and Sb-rich soils. Tailings and soil samples were obtained at the Mexican historical mining zone of Zimapán, Central México. More than 6 tailings impoundments are located at the town outskirts and constitute a contamination source from windblown and waterborne deposit on soils, besides acid mine drainage. Four substrates were used in the experiments: 100% tailings, 20% tailings + 80% soil, 50% tailings + 50% soil , and a soil sample far from tailings as a background. Concentrations of Sb ranged from 310 mg/kg to 413 mg/kg in tailings. A pH of 7.43, 1.27% organic matter, and high concentrations of N, K and P indicated adequate conditions for plant growth. The grass assemblage was raised during 21 days as indicated by OECD (Organisation for Economic Co-operation and Development) Guideline 208 Terrestrial Plant Test: Seedling Emergence and Seedling Growth Test. The highest Sb concentrations were measured in plants grown on tailings with 139 mg/kg in the aerial part and 883 mg/kg in roots. Concentrations of Sb decreased as the proportion of tailings diminished with 22.1 mg/kg in the aerial part and 10 mg/kg in roots corresponding to the plants grown in the 20 % tailings + 80% soil . Bioaccumulation (BAC) and bioconcentration factors (BF) of plants grown on tailings (BAC= 0.42, BCF=3.93) indicated their suitability as a phyto-stabilization option. The grass mixture may be thus applied to control windblown particulate tailings taking advantage to their tolerance to high Sb levels.

Arsenic bioaccumulation in a marine juvenile fish Terapon jarbua

International Nuclear Information System (INIS)

Zhang Wei; Huang Liangmin; Wang Wenxiong

2011-01-01

Highlights: Radiotracer technique was used to quantify the biokinetics of As(V) in a marine fish. As(V) had a low bioavailability to Terapon jarbua. Dietary assimilation of As was only 3.1–7.4% for fish fed with different preys. Dietary uptake could be the primary route for As bioaccumulation in fish. - Abstract: Arsenic (As) is a ubiquitous toxic metalloid that is causing widespread public concern. Recent measurements have indicated that some marine fish in China might be seriously contaminated with As. Yet the biokinetics and bioaccumulation pathway of As in fish remain little understood. In this study, we employed a radiotracer technique to quantify the dissolved uptake, dietary assimilation and subsequent efflux of As(V) in a marine predatory fish, Terapon jarbua. The dissolved uptake of As showed a linear pattern over a range of dissolved concentrations from 0.5 to 50 μg L −1 , with a corresponding uptake rate constant of 0.0015 L g −1 d −1 . The assimilation efficiencies (AEs) of dietary As were only 3.1–7.4% for fish fed with copepods, clams, prey fish, or artificial diets, and were much lower than the As that entered the trophically available metal fraction in the prey. The dietary AEs were independent of the As(V) concentrations in the artificial diets. The efflux rate constant of As in fish following the dietary exposure was 0.03 d −1 . Modeling calculations showed that dietary uptake could be the primary route for As bioaccumulation in fish, and the corresponding contributions of waterborne and dietary uptakes were related to the bioconcentration factor (BCF) of the prey and the ingestion rate of fish. This study demonstrates that As(V) has a low bioavailability to T. jarbua.

Bioaccumulation factor of 137Cs in some marine biotas from West Bangka Indonesia

Science.gov (United States)

Suseno, Heny

2014-03-01

Radionuclides may be released from nuclear facilities to the marine environment. Concentrations of radionuclides within marine biotic systems can be influenced by a number of factors, including the type of biota, its source, the radionuclide, and specific characteristics of the sampled specimens and the marine environment (salinity, etc.). The bioconcentration factor for a marine organism is the ratio of the concentration of a radionuclide in that organism to the concentration found in its marine water environment - under conditions of equilibrium. Information on the bioaccumulation of Cs-137 in marine organisms is required to risk assessment evaluates the potential risks to human health. Bioaccumulation of Cs was investigated in marine biota from west Bangka such as Marine cat fish (Arius thalassinus), Baramundi (Lates calcarifer), Mackerel (Scomberomorus commerson), Striped eel catfish (Plotosus lineatus), eel tailed fish (Euristhmus microceps), Yellowtail fusilier (Caesio erythrogaster), Coastal crab (Scylla sp), White shrimp (Penaeus merguiensis) and marine bivalve mollusk (Anadara granosa). Muscle of these marine biota, sediments and water were assayed for Cs-137 by HPGe gamma spectrometer. The bioaccumulation factor for fishes were calculated by ratio of concentration Cs-137 in muscle biota to the its concentration in water. The bioaccumulation factor for mollusks were calculates by ratio of concentration Cs-137 in muscle biota to the its concentration in sediments. The bioaccumulation factor were range 4.99 to 136.34.

Bioaccumulation factor of 137Cs in some marine biotas from West Bangka Indonesia

International Nuclear Information System (INIS)

Suseno, Heny

2014-01-01

Radionuclides may be released from nuclear facilities to the marine environment. Concentrations of radionuclides within marine biotic systems can be influenced by a number of factors, including the type of biota, its source, the radionuclide, and specific characteristics of the sampled specimens and the marine environment (salinity, etc.). The bioconcentration factor for a marine organism is the ratio of the concentration of a radionuclide in that organism to the concentration found in its marine water environment - under conditions of equilibrium. Information on the bioaccumulation of Cs-137 in marine organisms is required to risk assessment evaluates the potential risks to human health. Bioaccumulation of Cs was investigated in marine biota from west Bangka such as Marine cat fish (Arius thalassinus), Baramundi (Lates calcarifer), Mackerel (Scomberomorus commerson), Striped eel catfish (Plotosus lineatus), eel tailed fish (Euristhmus microceps), Yellowtail fusilier (Caesio erythrogaster), Coastal crab (Scylla sp), White shrimp (Penaeus merguiensis) and marine bivalve mollusk (Anadara granosa). Muscle of these marine biota, sediments and water were assayed for Cs-137 by HPGe gamma spectrometer. The bioaccumulation factor for fishes were calculated by ratio of concentration Cs-137 in muscle biota to the its concentration in water. The bioaccumulation factor for mollusks were calculates by ratio of concentration Cs-137 in muscle biota to the its concentration in sediments. The bioaccumulation factor were range 4.99 to 136.34

LNG imports make strong recovery in 1996; exports increase also

International Nuclear Information System (INIS)

Swain, E.J.

1998-01-01

LNG imports to the US jumped in 1996 as Algerian base-load plants resumed operations following major revamps. Exports from Alaska to Japan grew by nearly 4% over 1995. Total LNG imports to the US in 1996 were 40.27 bcf compared to 17.92 bcf in 1995, an increase of 124.8%. Algeria supplied 35.32 bcf; Abu Dhabi, 4.95 bcf. About 82.3% of the imported LNG was received at Distrigas Corp.'s terminal north of Boston. The remaining LNG was received at the Pan National terminal in Lake Charles, LA. LNG imports during 1995 fell to such a low level not because of depressed US demand but because of limited supply. The paper discusses LNG-receiving terminals, base-load producers, LNG pricing, and exports

Marker-Assisted Backcrossing to Develop an Elite Cytoplasmic Male Sterility Line in Rice

Directory of Open Access Journals (Sweden)

Asadollah Ahmadikhah

2015-07-01

Full Text Available Cytoplasmic male sterility (CMS is a cornerstone of hybrid production in many crops. In three-line hybrid systems, use of CMS, maintainer, and fertility restorer lines is necessary for production of hybrid seeds. Limited resources of CMS and low variation of CMS lines cause genetic vulnerability to pathogens. Therefore, diversifying the CMS sources is indispensible for a sustainable production system of hybrid seed. In this study, we attempted for the first time to transfer CMS into maintainer line Yosen B in restricted generations using the marker-assisted backcrossing (MABC method. The resultant F hybrid of IR68897 A/Yosen B cross was backcrossed to Yosen B, and CMS plants in each backcross generation (from BCF to BCF were selected based on phenotyping test and MABC. Molecular assessment of backcross progenies was conducted using a mitochondrial CMS-specific marker and 34 polymorphic nuclear simple-sequence repeat (SSR markers in early generations (from BCF to BCF and was continued using 9 additional SSRs and 82 inter-simple sequence repeat (ISSR markers in BCF. A MABC strategy could successfully recover the recurrent parent genome (RPG in BCF generation, and decreased heterozygosity of final CMS plants. Restorability test with known wild-abortive restorer lines (viz. IR36 and IR24 showed that combination of Yosen A × IR24 could produce highly fertile F hybrid. Evaluation of some important agronomic traits of the final CMS line (BCF at field condition showed that it was comparable to the original maintainer fertile counterpart. Phenotypic and marker-assisted selections could considerably decrease the time needed for full recovery of RPG so that final CMS line could show a high similarity to original fertile counterpart.

Bauhinia championii Flavone Attenuates Hypoxia-Reoxygenation Induced Apoptosis in H9c2 Cardiomyocytes by Improving Mitochondrial Dysfunction.

Science.gov (United States)

Liao, Ping; Sun, Guibo; Zhang, Chan; Wang, Min; Sun, Yao; Zhou, Yuehan; Sun, Xiaobo; Jian, Jie

2016-11-04

This study aimed to determine the effects of Bauhinia championii flavone (BCF) on hypoxia-reoxygenation (H/R) induced apoptosis in H9c2 cardiomyocytes and to explore potential mechanisms. The H/R model in H9c2 cardiomyocytes was established by 6 h of hypoxia and 12 h of reoxygenation. Cell viability was detected by CCK-8 assay. Apoptotic rate was measured by Annexin V/PI staining. Levels of mitochondria-associated ROS, mitochondrial transmembrane potential (∆Ψm) and mitochondrial permeability transition pores (MPTP) opening were assessed by fluorescent probes. ATP production was measured by ATP assay kit. The release of cytochrome c, translocation of Bax, and related proteins were measured by western blotting. Our results showed that pretreatment with BCF significantly improved cell viability and attenuated the cardiomyocyte apoptosis caused by H/R. Furthermore, BCF increased ATP production and inhibited ROS-generating mitochondria, depolarization of ΔΨm, and MPTP opening. Moreover, BCF pretreatment decreased Bax mitochondrial translocation, cytochrome c release, and activation of caspase-3, as well as increased the expression of p-PI3K, p-Akt, and the ratio of Bcl-2 to Bax. Interestingly, a specific inhibitor of phosphatidylinositol 3-kinase, LY294002, partly reversed the anti-apoptotic effect of BCF. These observations indicated that BCF pretreatment attenuates H/R-induced myocardial apoptosis strength by improving mitochondrial dysfunction via PI3K/Akt signaling pathway.

Role of Phragmites australis (common reed) for heavy metals phytoremediation of estuarine sediments.

Science.gov (United States)

Cicero-Fernández, Diego; Peña-Fernández, Manuel; Expósito-Camargo, Jose A; Antizar-Ladislao, Blanca

2016-01-01

The ability of Phragmites australis to take up heavy metals (Co, Ni, Mo, Cd, Pb, Cr, Cu, Fe, Mn, Zn, and Hg) and other trace elements (As, Se, Ba), from estuarine sediments was investigated using a pilot plant experimental approach. Bioaccumulation (BCF) and translocation factors (TF) were calculated in vegetative and senescence periods for two populations of P. australis, from contaminated (MIC) and non-contaminated (GAL) estuarine sediments, respectively, both growing in estuarine contaminated sediment (RIA) from ría del Carmen y Boo, Santander Bay, Spain. The highest BCF values were obtained for Ni (0.43), Ba (0.43) Mo (0.36), Cr (0.35), and Cd (0.31) for plants collected from site GAL following the senescence period. The highest BCF values recorded for plants collected from MIC following the senescence period were for Mo (0.22) and Cu (0.22). Following senescence, plants collected from GAL and MIC presented TF>1 for Ni, Mo, Se, and Zn, and in addition plants collected from MIC presented TF>1 for Ba, Cr, and Mn. A substantial increase of Micedo's rhizosphere, six times higher than Galizano's rhizosphere, suggested adaptation to contaminated sediment. The evaluated communities of P. australis demonstrated their suitability for phytoremediation of heavy metals contaminated estuarine sediments.

Bioaccumulation factor of {sup 137}Cs in some marine biotas from West Bangka Indonesia

Energy Technology Data Exchange (ETDEWEB)

Suseno, Heny, E-mail: henis@batan.go.id [Radioactive Waste Technology Center - The Indonesia Nuclear Energy Agency (BATAN) (Indonesia)

2014-03-24

Radionuclides may be released from nuclear facilities to the marine environment. Concentrations of radionuclides within marine biotic systems can be influenced by a number of factors, including the type of biota, its source, the radionuclide, and specific characteristics of the sampled specimens and the marine environment (salinity, etc.). The bioconcentration factor for a marine organism is the ratio of the concentration of a radionuclide in that organism to the concentration found in its marine water environment - under conditions of equilibrium. Information on the bioaccumulation of Cs-137 in marine organisms is required to risk assessment evaluates the potential risks to human health. Bioaccumulation of Cs was investigated in marine biota from west Bangka such as Marine cat fish (Arius thalassinus), Baramundi (Lates calcarifer), Mackerel (Scomberomorus commerson), Striped eel catfish (Plotosus lineatus), eel tailed fish (Euristhmus microceps), Yellowtail fusilier (Caesio erythrogaster), Coastal crab (Scylla sp), White shrimp (Penaeus merguiensis) and marine bivalve mollusk (Anadara granosa). Muscle of these marine biota, sediments and water were assayed for Cs-137 by HPGe gamma spectrometer. The bioaccumulation factor for fishes were calculated by ratio of concentration Cs-137 in muscle biota to the its concentration in water. The bioaccumulation factor for mollusks were calculates by ratio of concentration Cs-137 in muscle biota to the its concentration in sediments. The bioaccumulation factor were range 4.99 to 136.34.

Acute exposure to synthetic pyrethroids causes bioconcentration and disruption of the hypothalamus–pituitary–thyroid axis in zebrafish embryos

International Nuclear Information System (INIS)

Tu, Wenqing; Xu, Chao; Lu, Bin; Lin, Chunmian; Wu, Yongming; Liu, Weiping

2016-01-01

Synthetic pyrethroids (SPs) have the potential to disrupt the thyroid endocrine system in mammals; however, little is known of the effects of SPs and underlying mechanisms in fish. In the current study, embryonic zebrafish were exposed to various concentrations (1, 3 and 10 μg/L) of bifenthrin (BF) or λ-cyhalothrin (λ-CH) until 72 h post fertilization, and body condition, bioaccumulation, thyroid hormone levels and transcription of related genes along the hypothalamus–pituitary–thyroid (HPT) axis examined. Body weight was significantly decreased in the λ-CH exposure groups, but not the BF exposure groups. BF and λ-CH markedly accumulated in the larvae, with concentrations ranging from 90.7 to 596.8 ng/g. In both exposure groups, alterations were observed in thyroxine (T 4 ) and triiodothyronine (T 3 ) levels. In addition, the majority of the HPT axis-related genes examined, including CRH, TSHβ, TTR, UGT1ab, Pax8, Dio2 and TRα, were significantly upregulated in the presence of BF. Compared to BF, λ-CH induced different transcriptional regulation patterns of the tested genes, in particular, significant stimulation of TTR, Pax8, Dio2 and TRα levels along with concomitant downregulation of Dio1. Molecular docking analyses revealed that at the atomic level, BF binds to thyroid hormone receptor (TRα) protein more potently than λ-CH, consequently affecting HPT axis signal transduction. In vitro and in silico experiments disclosed that during the early stages of zebrafish development, BF and λ-CH have the potential to disrupt thyroid endocrine system. - Highlights: • Following respective exposure of embryos to BF and λ-CH, thyroid endocrine disruption was investigated in zebrafish embryos. • Thyroid hormones (T3 and T4 levels) were significantly altered after being exposed to BF and λ-CH. • Gene transcription modulation in the HPT axis was examined. • BF and λ-CH bioconcentration in zebrafish larvae were evident. • BF binds to thyroid hormone

Acute exposure to synthetic pyrethroids causes bioconcentration and disruption of the hypothalamus–pituitary–thyroid axis in zebrafish embryos

Energy Technology Data Exchange (ETDEWEB)

Tu, Wenqing [Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang 330029 (China); Institute of Environmental Science, College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Xu, Chao, E-mail: chaoxu@zjut.edu.cn [Institute of Environmental Science, College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Lu, Bin; Lin, Chunmian [Institute of Environmental Science, College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Wu, Yongming [Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang 330029 (China); Liu, Weiping [Institute of Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China)

2016-01-15

Synthetic pyrethroids (SPs) have the potential to disrupt the thyroid endocrine system in mammals; however, little is known of the effects of SPs and underlying mechanisms in fish. In the current study, embryonic zebrafish were exposed to various concentrations (1, 3 and 10 μg/L) of bifenthrin (BF) or λ-cyhalothrin (λ-CH) until 72 h post fertilization, and body condition, bioaccumulation, thyroid hormone levels and transcription of related genes along the hypothalamus–pituitary–thyroid (HPT) axis examined. Body weight was significantly decreased in the λ-CH exposure groups, but not the BF exposure groups. BF and λ-CH markedly accumulated in the larvae, with concentrations ranging from 90.7 to 596.8 ng/g. In both exposure groups, alterations were observed in thyroxine (T{sub 4}) and triiodothyronine (T{sub 3}) levels. In addition, the majority of the HPT axis-related genes examined, including CRH, TSHβ, TTR, UGT1ab, Pax8, Dio2 and TRα, were significantly upregulated in the presence of BF. Compared to BF, λ-CH induced different transcriptional regulation patterns of the tested genes, in particular, significant stimulation of TTR, Pax8, Dio2 and TRα levels along with concomitant downregulation of Dio1. Molecular docking analyses revealed that at the atomic level, BF binds to thyroid hormone receptor (TRα) protein more potently than λ-CH, consequently affecting HPT axis signal transduction. In vitro and in silico experiments disclosed that during the early stages of zebrafish development, BF and λ-CH have the potential to disrupt thyroid endocrine system. - Highlights: • Following respective exposure of embryos to BF and λ-CH, thyroid endocrine disruption was investigated in zebrafish embryos. • Thyroid hormones (T3 and T4 levels) were significantly altered after being exposed to BF and λ-CH. • Gene transcription modulation in the HPT axis was examined. • BF and λ-CH bioconcentration in zebrafish larvae were evident. • BF binds to thyroid

The bioconcentration of 131I in fresh water fish

International Nuclear Information System (INIS)

Yu, K.N.; Cheung, T.; Young, E.C.M.; Luo, D.L.

1996-01-01

The dynamic characteristics of the radionuclide concentration process in fresh water fish have been studied. The experimental data for the tilapias were fitted using a simple compartment model to get characteristics parameters such as concentration factors, elimination rate constants, and initial concentration rates, which are 3.08 Bq kg -1 /Bq L -1 , 0.00573 h -1 , and 12.42 Bq kg -1 h -1 , respectively. The relative concentrations of 131 I in different parts, i.e., head, gills, flesh, bone and internal organs, of the tilapias are also determined, which are found to be 10.8, 15.4, 26.1, 11.0, and 37.0%, respectively. The effects of different factors on the transfer of radionuclides in fresh water fishes are also discussed. Experiments on the tilapias and the common carp show that the variation of concentration factors for different species may be significant even for the same radionuclide and the same ecological system. On the other hand, the variation in the concentration factors for the flesh of the tilapias is not significant for a certain range of 131 I concentrations in the water. 12 refs., 1 fig., 1 tab

Aquatic fate of synfuel residuals: bioaccumulation of aniline and phenol by the freshwater phytoplankter Scenedesmus quadricauda

International Nuclear Information System (INIS)

Hardy, J.T.; Dauble, D.D.; Felice, L.J.

1985-01-01

Coal liquefaction compounds could, through accidental release, enter aquatic environments. Experiments were conducted to determine the kinetics, degree of bioconcentration and stability of two of these compounds at the first level of aquatic food web. The authors exposed the freshwater phytoplankter Scenedesmus quadricauda to sublethal concentrations of 14 C-labeled phenol and aniline. Both accumulation and elimination occurred within a few hours and followed hyperbolic kinetics. Results indicate that substantial quantities of accumulated compounds remain as the parent compound (22% for phenol and 52% for aniline) for up to 24 h and could be available to animals higher in the food web. Bioconcentration factors were 3.5 for phenol and 91 for aniline. 24 references, 2 figures, 1 table

Predicting the bioaccumulation of polyaromatic hydrocarbons and polychlorinated biphenyls in benthic animals in sediments

Energy Technology Data Exchange (ETDEWEB)

Tuikka, A.I., E-mail: anitat@student.uef.fi [University of Eastern Finland, Department of Environmental and Biological Sciences, P.O. Box 111, FI-80101 Joensuu (Finland); Leppänen, M.T., E-mail: Matti.T.Leppanen@ymparisto.fi [Finnish Environment Institute, Laboratories/Research and Innovation Laboratory, P.O. Box 35, University of Jyväskylä, FI-40014 Jyväskylä (Finland); Akkanen, J., E-mail: jarkko.akkanen@uef.fi [University of Eastern Finland, Department of Environmental and Biological Sciences, P.O. Box 111, FI-80101 Joensuu (Finland); Sormunen, A.J., E-mail: Arto.Sormunen@mamk.fi [University of Eastern Finland, Department of Environmental and Biological Sciences, P.O. Box 111, FI-80101 Joensuu (Finland); Leonards, P.E.G., E-mail: pim.leonards@vu.nl [Institute for Environmental Studies, Vrije Universiteit Amsterdam, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands); Hattum, B. van, E-mail: bert.vanhattum@deltares.nl [Institute for Environmental Studies, Vrije Universiteit Amsterdam, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands); Vliet, L.A. van, E-mail: lavanvliet@hotmail.com [Ministry of Transport, Public Works and Water Management, National Institute for Coastal and Marine Management/RIKZ, P.O. Box 207, 9750 AE Haren (Netherlands); Brack, W., E-mail: werner.brack@ufz.de [Helmholtz Centre for Environmental Research - UFZ, Department of Effect-Directed Analysis, Permoserstraße 15, 04318 Leipzig (Germany); Smedes, F., E-mail: smedes@recetox.muni.cz [Ministry of Transport, Public Works and Water Management, National Institute for Coastal and Marine Management/RIKZ, P.O. Box 207, 9750 AE Haren (Netherlands); and others

2016-09-01

There were two main objectives in this study. The first was to compare the accuracy of different prediction methods for the chemical concentrations of polyaromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in the organism, based on the measured chemical concentrations existing in sediment dry matter or pore water. The predicted tissue concentrations were compared to the measured ones after 28-day laboratory test using oligochaeta worms (Lumbriculus variegatus). The second objective was to compare the bioaccumulation of PAHs and PCBs in the laboratory test with the in situ bioaccumulation of these compounds. Using the traditional organic carbon-water partitioning model, tissue concentrations were greatly overestimated, based on the concentrations in the sediment dry matter. Use of an additional correction factor for black carbon with a two-carbon model, significantly improved the bioaccumulation predictions, thus confirming that black carbon was important in binding the chemicals and reducing their accumulation. The predicted PAH tissue concentrations were, however, high compared to the observed values. The chemical concentrations were most accurately predicted from their freely dissolved pore water concentrations, determined using equilibrium passive sampling. The patterns of PCB and PAH accumulation in sediments for laboratory-exposed L. variegatus were similar to those in field-collected Lumbriculidae worms. Field-collected benthic invertebrates and L. variegatus accumulated less PAHs than PCBs with similar lipophilicity. The biota to sediment accumulation factors of PAHs tended to decrease with increasing sediment organic carbon normalized concentrations. The presented data yields bioconcentration factors (BCF) describing the chemical water-lipid partition, which were found to be higher than the octanol-water partition coefficients, but on a similar level with BCFs drawn from relevant literature. In conclusion, using the two-carbon model method

On the Connection between Kinetic Monte Carlo and the Burton-Cabrera-Frank Theory

Science.gov (United States)

Patrone, Paul; Margetis, Dionisios; Einstein, T. L.

2013-03-01

In the many years since it was first proposed, the Burton- Cabrera-Frank (BCF) model of step-flow has been experimentally established as one of the cornerstones of surface physics. However, many questions remain regarding the underlying physical processes and theoretical assumptions that give rise to the BCF theory. In this work, we formally derive the BCF theory from an atomistic, kinetic Monte Carlo model of the surface in 1 +1 dimensions with one step. Our analysis (i) shows how the BCF theory describes a surface with a low density of adsorbed atoms, and (ii) establishes a set of near-equilibrium conditions ensuring that the theory remains valid for all times. Support for PP was provided by the NIST-ARRA Fellowship Award No. 70NANB10H026 through UMD. Support for TLE and PP was also provided by the CMTC at UMD, with ancillary support from the UMD MRSEC. Support for DM was provided by NSF DMS0847587 at UMD.

Short-term bioconcentration studies of Np in freshwater biota

International Nuclear Information System (INIS)

Poston, T.M.; Klopfer, D.C.; Simmons, M.A.

1990-01-01

Short-term laboratory exposures were conducted to determine the potential accumulation of Np in aquatic organisms. Concentration factors were highest in green algae. Daphnia magna, a filter-feeding crustacean, accumulated Np at levels one order of magnitude greater than the amphipod Gammarus sp., an omnivorous substrate feeder. Accumulation of Np in juvenile rainbow trout (Oncorhynchus mykiss) was highest in carcass (generally greater than 78% of the total body burden) and lowest in fillets. Recommended concentration factors for Np, based on fresh weight, were 300 for green algae, 100 for filter-feeding invertebrates, for nonfilter-feeding invertebrates, 10 for whole fish, and one for fish flesh

Model evaluation of the phytoextraction potential of heavy metal hyperaccumulators and non-hyperaccumulators

Energy Technology Data Exchange (ETDEWEB)

Liang, H.-M. [Agricultural Biotechnology Research Center, Academia Sinica, 128 Section 2, Academia Road, Taipei, Taiwan 11529, Taiwan (China); Lin, T.-H. [Department of Statistics, National Taipei University, Taiwan (China); Chiou, J.-M. [Institute of Statistical Science, Academia Sinica, Taiwan (China); Yeh, K.-C., E-mail: kcyeh@gate.sinica.edu.t [Agricultural Biotechnology Research Center, Academia Sinica, 128 Section 2, Academia Road, Taipei, Taiwan 11529, Taiwan (China)

2009-06-15

Evaluation of the remediation ability of zinc/cadmium in hyper- and non-hyperaccumulator plant species through greenhouse studies is limited. To bridge the gap between greenhouse studies and field applications for phytoextraction, we used published data to examine the partitioning of heavy metals between plants and soil (defined as the bioconcentration factor). We compared the remediation ability of the Zn/Cd hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri and the non-hyperaccumulators Nicotiana tabacum and Brassica juncea using a hierarchical linear model (HLM). A recursive algorithm was then used to evaluate how many harvest cycles were required to clean a contaminated site to meet Taiwan Environmental Protection Agency regulations. Despite the high bioconcentration factor of both hyperaccumulators, metal removal was still limited because of the plants' small biomass. Simulation with N. tabacum and the Cadmium model suggests further study and development of plants with high biomass and improved phytoextraction potential for use in environmental cleanup. - A quantitative solution enables the evaluation of Zn/Cd phytoextraction.

Model evaluation of the phytoextraction potential of heavy metal hyperaccumulators and non-hyperaccumulators.

Science.gov (United States)

Liang, Hong-Ming; Lin, Ting-Hsiang; Chiou, Jeng-Min; Yeh, Kuo-Chen

2009-06-01

Evaluation of the remediation ability of zinc/cadmium in hyper- and non-hyperaccumulator plant species through greenhouse studies is limited. To bridge the gap between greenhouse studies and field applications for phytoextraction, we used published data to examine the partitioning of heavy metals between plants and soil (defined as the bioconcentration factor). We compared the remediation ability of the Zn/Cd hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri and the non-hyperaccumulators Nicotiana tabacum and Brassica juncea using a hierarchical linear model (HLM). A recursive algorithm was then used to evaluate how many harvest cycles were required to clean a contaminated site to meet Taiwan Environmental Protection Agency regulations. Despite the high bioconcentration factor of both hyperaccumulators, metal removal was still limited because of the plants' small biomass. Simulation with N. tabacum and the Cadmium model suggests further study and development of plants with high biomass and improved phytoextraction potential for use in environmental cleanup.

Model evaluation of the phytoextraction potential of heavy metal hyperaccumulators and non-hyperaccumulators

International Nuclear Information System (INIS)

Liang, H.-M.; Lin, T.-H.; Chiou, J.-M.; Yeh, K.-C.

2009-01-01

Evaluation of the remediation ability of zinc/cadmium in hyper- and non-hyperaccumulator plant species through greenhouse studies is limited. To bridge the gap between greenhouse studies and field applications for phytoextraction, we used published data to examine the partitioning of heavy metals between plants and soil (defined as the bioconcentration factor). We compared the remediation ability of the Zn/Cd hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri and the non-hyperaccumulators Nicotiana tabacum and Brassica juncea using a hierarchical linear model (HLM). A recursive algorithm was then used to evaluate how many harvest cycles were required to clean a contaminated site to meet Taiwan Environmental Protection Agency regulations. Despite the high bioconcentration factor of both hyperaccumulators, metal removal was still limited because of the plants' small biomass. Simulation with N. tabacum and the Cadmium model suggests further study and development of plants with high biomass and improved phytoextraction potential for use in environmental cleanup. - A quantitative solution enables the evaluation of Zn/Cd phytoextraction.

Clustering pesticides according to their molecular properties and their impacts by considering additional ecotoxicological parameters in the TyPol method

Science.gov (United States)

Traore, Harouna; Crouzet, Olivier; Mamy, Laure; Sireyjol, Christine; Rossard, Virginie; Servien, Remy; Latrille, Eric; Benoit, Pierre

2017-04-01

The understanding of the fate of pesticides and their environmental impacts largely relies on their molecular properties. We recently developed 'TyPol' (Typology of Pollutants), a clustering method based on statistical analyses combining several environmental endpoints (i.e. environmental parameters such as sorption coefficient, degradation half-life) and one ecotoxicological one (bioconcentration factor), and structural molecular descriptors (number of atoms in the molecule, molecular surface, dipole moment, energy of orbitals…). TyPol has been conceived on the available knowledge on QSAR of a wide diversity of organic compounds (Mamy et al., 2015). This approach also allows to focus on transformation products present in different clusters and to infer possible changes in environmental fate consecutively to different degradation processes (Servien et al., 2014; Benoit et al., 2016). The initial version of TyPol did not include any ecotoxicological parameters except the bioconcentration factor (BCF), which informs more on the transfer along the trophic chain rather than on the effects on non-target organisms. The objective was to implement the TyPol database with a data set of ecotoxicological data concerning pesticides and several aquatic and terrestrial organisms, in order to test the possibility to extend TyPol to ecotoxicological effects on various organisms. The data analysis (available literature and databases) revealed that relevant ecotoxicological endpoints for terrestrial organisms such as soil microorganisms and macroinvertebrates are lacking compared to aquatic organisms. We have added seven parameters for acute (EC50, LC50) and chronic (NOEC) toxicological effects for the following organisms: Daphnia, Algae, Lemna and Earthworm. In this new configuration, TyPol was used to classify about 45 pesticides in different behavioural and ecotoxicity clusters. The clustering results were analyzed to reveals relationships between molecular descriptors

Discriminatory ability of simple OGTT-based beta cell function indices for prediction of prediabetes and type 2 diabetes: the CODAM study.

Science.gov (United States)

den Biggelaar, Louise J C J; Sep, Simone J S; Eussen, Simone J P M; Mari, Andrea; Ferrannini, Ele; van Greevenbroek, Marleen M J; van der Kallen, Carla J H; Schalkwijk, Casper G; Stehouwer, Coen D A; Dagnelie, Pieter C

2017-03-01

The hyperglycaemic clamp technique and the frequently sampled IVGTT are unsuitable techniques to assess beta cell function (BCF) in large cohorts. Therefore, the aim of this study was to evaluate the discriminatory ability of simple OGTT-based BCF indices for prediction of prediabetes (meaning impaired fasting glucose and/or impaired glucose tolerance) and type 2 diabetes. Glucose metabolism status was assessed by 2 h 75 g OGTT at baseline (n = 476, mean age 59.2 years, 38.7% women) and after 7 years of follow-up (n = 416) in the Cohort on Diabetes and Atherosclerosis Maastricht (CODAM) study (1999-2009). Baseline plasma glucose, insulin and C-peptide values during OGTTs were used to calculate 21 simple indices of BCF. Disposition indices (BCF index × Matsuda index), to compensate for the prevailing level of insulin resistance, were calculated for the BCF indices with the best discriminatory abilities. The discriminatory ability of the BCF indices was estimated by the area under the receiver operating characteristics curve (ROC AUC) with an outcome of incident prediabetes (n = 73) or type 2 diabetes (n = 60 and n = 18 cases, respectively, in individuals who were non-diabetic or had normal glucose metabolism at baseline). For incident prediabetes (n = 73), all ROC AUCs were less than 70%, whereas for incident type 2 diabetes, I 30 /I 0 , CP 30 /CP 0 , ΔI 30 /ΔG 30 , ΔCP 30 /ΔG 30 (where I, CP and G are the plasma concentrations of insulin, C-peptide and glucose, respectively, at the times indicated), and corrected insulin response at 30 min had ROC AUCs over 70%. In at-baseline non-diabetic individuals, disposition indices ΔI 30 /ΔG 30 , ΔCP 30 /ΔG 30 and corrected insulin response at 30 min had ROC AUCs of over 80% for incident type 2 diabetes. Moreover, these BCF disposition indices had significantly better discriminatory abilities for incident type 2 diabetes than the Matsuda index alone. BCF indices reflecting early

Uptake of trace elements and PAHs by fruit and vegetables from contaminated soils

DEFF Research Database (Denmark)

Samsøe-Petersen, L.; Larsen, Erik Huusfeldt; Larsen, P.B.

2002-01-01

1, except for those of Cd in lettuce and carrot with peel from uncontaminated soil. In most cases, BCF values were decreasing with increasing concentrations in soil. From the heavily contaminated soil, BCF values for Pb in lettuce, potato, and carrot with peel were 0.001, 0.002, and 0...

A review of measured bioaccumulation data in terrestrial plants for organic chemicals: Metrics, variability and the need for standardized measurement protocols

DEFF Research Database (Denmark)

Doucette, William J; Shunthirasingham, Chubashini; Dettenmaier, Erik M

2018-01-01

by plants are often expressed as ratios of chemical concentrations in the plant compartments of interest (e.g., leaves, shoots, roots, xylem sap) to that in the exposure medium (e.g., soil, soil pore water, hydroponic solution, air). These ratios are generally referred to as bioconcentration factors (BCFs...

Hazard assessment of metals in invasive fish species of the Yamuna River, India in relation to bioaccumulation factor and exposure concentration for human health implications.

Science.gov (United States)

Singh, Atul K; Srivastava, Sharad C; Verma, Pankaj; Ansari, Abubakar; Verma, Ambrish

2014-06-01

Monitoring of heavy metals was conducted in the Yamuna River considering bioaccumulation factor, exposure concentration, and human health implications which showed contamination levels of copper (Cu), lead (Pb), nickel (Ni), and chromium (Cr) and their dispersion patterns along the river. Largest concentration of Pb in river water was 392 μg L(-1); Cu was 392 μg L(-1) at the extreme downstream, Allahabad and Ni was 146 μg L(-1) at midstream, Agra. Largest concentration of Cu was 617 μg kg(-1), Ni 1,621 μg kg(-1) at midstream while Pb was 1,214 μg kg(-1) at Allahabad in surface sediment. The bioconcentration of Cu, Pb, Ni, and Cr was observed where the largest accumulation of Pb was 2.29 μg kg(-1) in Oreochromis niloticus and 1.55 μg kg(-1) in Cyprinus carpio invaded at Allahabad while largest concentration of Ni was 174 μg kg(-1) in O. niloticus and 124 μg kg(-1) in C. carpio in the midstream of the river. The calculated values of hazard index (HI) for Pb was found more than one which indicated human health concern. Carcinogenic risk value for Ni was again high i.e., 17.02 × 10(-4) which was larger than all other metals studied. The results of this study indicated bioconcentration in fish due to their exposures to heavy metals from different routes which had human health risk implications. Thus, regular environmental monitoring of heavy metal contamination in fish is advocated for assessing food safety since health risk may be associated with the consumption of fish contaminated through exposure to a degraded environment.

Absorption and translocation of polybrominated diphenyl ethers (PBDEs) by plants from contaminated sewage sludge

Czech Academy of Sciences Publication Activity Database

Vrkoslavová, J.; Demnerová, K.; Macková, M.; Zemanová, T.; Macek, Tomáš; Hajšlová, J.; Pulkrabová, J.; Hrádková, P.; Stiborová, H.

2010-01-01

Roč. 81, č. 3 (2010), s. 381-386 ISSN 0045-6535 R&D Projects: GA MŠk 2B06151 Grant - others:GA ČR(CZ) GP104/08/P188 Institutional research plan: CEZ:AV0Z40550506 Keywords : polybrominated diphenyl ethers * contaminated sewage sludge * plant uptake * bioconcentration factors * Nicotiana tabacum Subject RIV: EI - Biotechnology ; Bionics Impact factor: 3.155, year: 2010

Techno-functional differentiation of two vitamin B12 producing Lactobacillus plantarum strains: an elucidation for diverse future use.

Science.gov (United States)

Bhushan, Bharat; Tomar, S K; Chauhan, Arun

2017-01-01

An appropriate selection of Lactobacillus strain (probiotic/starter/functional) on the basis of its techno-functional characteristics is required before developing a novel fermented functional food. We compared vitamin B 12 (B 12 , cobalamin) producing Lactobacillus plantarum isolates, BHM10 and BCF20, for functional (vitamin over-production, genomic insight to B 12 structural genes, and probiotic attributes) and technological [milks (skim and soy) fermentation and B 12 bio-fortification] characteristics. Addition of B 12 precursors (5-amonolevulinate and dimethylbenzimidazole) to cobalamin-free fermentation medium increased vitamin production in BHM10, BCF20, and DSM20016 (a positive standard) by 3.4-, 4.4-, and 3.86-folds, respectively. Three important B 12 structural genes were detected in L. plantarum species (strains BHM10 and BCF20) by PCR for the first time. The gene sequences were submitted to NCBI GenBank and found phylogenetically closer to respective sequences in B 12 producing Lactobacillus reuteri strains. During comparative probiotic testing, BCF20 showed significantly higher (p < 0.05 to p < 0.001) gastrointestinal tolerance and cell surface hydrophobicity (p < 0.05) than BHM10. Moreover, only BCF20 was found positive for BSH activity and also exhibited comparatively better antagonistic potential against potent pathogens. Conversely, high acid and bile susceptible strain BHM10 displayed significantly higher soy milk fermentation and resultant B 12 bio-fortification abilities during technological testing. Two B 12 quantification techniques, UFLC and competitive immunoassay, confirmed the in vitro and in situ bio-production of bio-available form of B 12 after BHM10 fermentation. Conclusively, techno-functional differentiation of two B 12 producing strains elucidates their diverse future use; BCF20 either for B 12 over-production (in vitro) or as a probiotic candidate, while BHM10 for cobalamin bio-fortification (in situ) in soy milk.

Different transfer pathways of an organochlorine pesticide across marine tropical food webs assessed with stable isotope analysis.

Directory of Open Access Journals (Sweden)

Charlotte R Dromard

Full Text Available Chlordecone is a persistent organochlorine pesticide used in the banana fields of the French West Indies from 1972 to 1993. Three marine habitats (mangroves, seagrass beds and coral reefs of two study sites located downstream contaminated rivers were chosen to evaluate the level of contamination of marine food webs. On each habitat, the food chain collected included suspended organic matter, primary producers (macroalgae, algal turf, seagrass, zooplankton, symbiotic organisms (corals, sea anemones, primary consumers (herbivores, suspension feeders, biofilm feeders, omnivores and detritivores (lobsters, fish, secondary consumers (carnivores 1: invertebrate feeders, planktivores and tertiary consumers (carnivores 2: invertebrate and fish feeders, piscivores. Log-linear regressions of the concentrations of chlordecone versus nitrogen isotopic ratios (δ15N were used to assess the bioaccumulation of chlordecone along trophic food webs. At each site, bioconcentration and bioamplification take part on the transfer of chlordecone in marine organisms. In mangroves (i.e. close to the source of pollution, lower trophic magnification factors (TMF indicated that bioconcentration prevailed over bioamplification phenomenon. The opposite phenomenon appeared on coral reefs in which bioconcentration processes were less important and bioamplification pathway became dominant. Far from the source of pollution, molecules of chlordecone seemed to be transfered to organisms mostly via trophic interactions rather than water contact.

Canadian natural gas winter 2005-06 outlook

International Nuclear Information System (INIS)

2005-11-01

An outline of the Canadian natural gas commodity market was presented along with an outlook for Canadian natural gas supply and prices for the winter heating season of 2005-2006. In Canada, the level of natural gas production is much higher than domestic consumption. In 2004, Canadian natural gas production was 16.9 billion cubic feet per day (Bcf/d), while domestic consumption was much lower at 8.2 Bcf/d. The United States, whose natural gas consumption is higher than production, imported about 16 per cent of its natural gas supply from Canada and 3 per cent from other countries via liquefied natural gas imports. Canadian natural gas exports to the United States in 2004 was 8.7 Bcf/d, representing 51 per cent of Canada's production. In Canada, the most important natural gas commodity markets that determine natural gas commodity prices include the intra-Alberta market and the market at the Dawn, Ontario natural gas hub. A well connected pipeline infrastructure connects the natural gas commodity markets in Canada and the United States, allowing supply and demand fundamentals to be transferred across all markets. As such, the integrated natural gas markets in both countries influence the demand, supply and price of natural gas. Canadian natural gas production doubled from 7 to 16.6 Bcf/d between 1986 and 2001. However, in the past 3 years, production from western Canada has leveled out despite record high drilling activity. This can be attributed to declining conventional reserves and the need to find new natural gas in smaller and lower-quality reservoirs. The combination of steady demand growth with slow supply growth has resulted in high natural gas prices since the beginning of 2004. In particular, hurricane damage in August 2005 disrupted natural gas production in the Gulf of Mexico's offshore producing region, shutting-in nearly 9 Bcf/d at the height of damage. This paper summarized some of the key factors that influence natural gas market and prices, with

Heavy metal phytoextraction-natural and EDTA-assisted remediation of contaminated calcareous soils by sorghum and oat.

Science.gov (United States)

Mahmood-Ul-Hassan, Muhammad; Suthar, Vishandas; Ahmad, Rizwan; Yousra, Munazza

2017-10-30

The abilities of sorghum (Sorghum bicolor L.) and oat (Avena sativa L.) to take up heavy metals from soils amended with ethylenediaminetetraacetic acid (EDTA) were assessed under greenhouse conditions. Both plants were grown in two soils contaminated with heavy metals (Gujranwala-silty loam and Pacca-clay loam). The soils were treated with 0, 0.625, 1.25, and 2.5 mM EDTA kg -1 soil applied at both 45 and 60 days after sowing (DAS); the experiment was terminated at 75 DAS. Addition of EDTA significantly increased concentrations of Cd, Cr, and Pb in roots and shoots, and bio-concentration factors and phytoextraction rates were also increased. Post-harvest soil analysis showed that soluble fractions of metals were also increased significantly. The increase in Cd was ≈ 3-fold and Pb was ≈ 15-fold at the highest addition of EDTA in Gujranwala soil; in the Pacca soil, the increase was less. Similarly, other phytoremediation factors, such as metal translocation, bio-concentration factor, and phytoextraction, efficiency were also maximum when soils were treated with 2.5 mM EDTA kg -1 soil. The study demonstrated that sorghum was better than oat for phytoremediation.

A Hierarchical Biology Concept Framework: A Tool for Course Design

OpenAIRE

Khodor, Julia; Halme, Dina Gould; Walker, Graham C.

2004-01-01

A typical undergraduate biology curriculum covers a very large number of concepts and details. We describe the development of a Biology Concept Framework (BCF) as a possible way to organize this material to enhance teaching and learning. Our BCF is hierarchical, places details in context, nests related concepts, and articulates concepts that are inherently obvious to experts but often difficult ...

Leveraging storage assets to meet winter power demand

Energy Technology Data Exchange (ETDEWEB)

Charleson, D. [Enbridge Gas Distribution, Toronto, ON (Canada)

2004-07-01

Toronto-based Enbridge Gas Distribution serves 1.7 million customers by distributing 420 billion cubic feet (BCF) of natural gas over more than 31,000 km of pipelines. A map of the franchise area was presented. The utility has one of the lowest operating and maintenance costs in North America. Daily gas requirements were outlined along with the historic role of storage in gas utilities. Storage is used by heat sensitive local distribution companies, marketers, large industrials, and power generators. Storage locations in North America were reviewed with reference to baseload electricity production versus peak load; depleted reservoirs; salt caverns; aquifers; and liquefied natural gas (LNG). Enbridge operates 98 BCF of storage facilities for a maximum deliverability of 1.7 BCF per day. tabs., figs.

Leveraging storage assets to meet winter power demand

International Nuclear Information System (INIS)

Charleson, D.

2004-01-01

Toronto-based Enbridge Gas Distribution serves 1.7 million customers by distributing 420 billion cubic feet (BCF) of natural gas over more than 31,000 km of pipelines. A map of the franchise area was presented. The utility has one of the lowest operating and maintenance costs in North America. Daily gas requirements were outlined along with the historic role of storage in gas utilities. Storage is used by heat sensitive local distribution companies, marketers, large industrials, and power generators. Storage locations in North America were reviewed with reference to baseload electricity production versus peak load; depleted reservoirs; salt caverns; aquifers; and liquefied natural gas (LNG). Enbridge operates 98 BCF of storage facilities for a maximum deliverability of 1.7 BCF per day. tabs., figs

U.S., Canadian pipelines producers lining up to meet Mexican gas demand growth

International Nuclear Information System (INIS)

Koen, A.D.

1992-01-01

This paper reports on prospects for continued strong growth in Mexican demand for natural gas imports that have U.S. and Canadian producers and pipelines queueing up to serve expected demand. In 1991, more than 25 U.S. companies exported a combined 61.7 bcf of gas into Mexico, an increase of more than 390% from 1990's total of 15.7 bcf. According to the Department of Energy Office of Fuels Programs (OFP), about 27.5 bcf of gas left the U.S. for Mexico in fourth quarter 1991 alone, an average 299 MMcfd. DOE has granted short term authorization to more than 65 countries to export gas into Mexico. Another 25 companies have short term export applications pending

A comparative study on the uptake and translocation of organochlorines by Phragmites australis

Energy Technology Data Exchange (ETDEWEB)

San Miguel, Angélique; Ravanel, Patrick [Laboratoire d’Ecologie Alpine, UMR CNRS n°5553, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09 (France); Raveton, Muriel, E-mail: muriel.raveton@ujf-grenoble.fr [Laboratoire d’Ecologie Alpine, UMR CNRS n°5553, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09 (France)

2013-01-15

Highlights: ► This study compares uptake/translocation of organochlorine congeners in macrophytes. ► First, root OC uptake was strongly linked with the partitioning/diffusion process. ► With time exposure, bioconcentration increased with OC solubility and volatility. ► Translocation was linked to the combination of water flow and vapor flux transfers. ► The most volatile OCs might be phytovolatilized from foliar surfaces. -- Abstract: Organochlorines (OCs) are persistent chemicals found in various environmental compartments. The differences in the uptake of {sup 14}C-labeled 1,4-dichlorobenzene (DCB), 1,2,4-trichlorobenzene (TCB) and γ-hexachlorocyclohexane (γHCH) by Phragmites australis were investigated under hydroponic conditions. The first step in sorption appears to be correlated with the hydrophobic nature of the compounds, since log-linear correlations were obtained between root concentration factor and partition coefficient (LogK{sub ow}). After 7 days of exposure, plant uptake of DCB, TCB, γHCH was significant with bioconcentration factors reaching 14, 19 and 15, respectively. Afterwards, uptake and translocation were seen to be more complex, with a loss of the simple relationship between uptake and LogK{sub ow}. Linear correlations between the bioconcentration/translocation factors and the physico-chemical properties of OCs were shown, demonstrating that translocation from roots to shoots increases with solubility and volatility of the OCs. This suggests that OC-translocation inside plants might result from the combination of two processes, xylem sap flow and vapor fluxes. {sup 14}C-phytovolatilization was measured and was correlated with the volatility of the compounds; the more volatile OCs being most the likely to be phytovolatilized from foliar surfaces (p = 0.0008). Thus, OC-uptake/translocation appears to proceed at a rate that depends mostly on the OCs hydrophobicity, solubility and volatility.

Potential for Phytoextraction of Cu by Sesamum indicum L. and Cyamopsis tetragonoloba L.: A Green Solution to Decontaminate Soil

Science.gov (United States)

Amin, Hira; Arain, Basir Ahmed; Abbasi, Muhammad Sadiq; Jahangir, Taj Muhammad; Amin, Farah

2018-05-01

Phytoextraction is a plant based-technique for removing toxic heavy metals from polluted soil. The experiment reported in this paper was undertaken to study the basic Cu phytoextraction potential of Sesamum indicum in comparison with Cyamopsis tetragonoloba for remediation of Cu contaminated soil in the framework of a pot-experiment. Plants were subjected to seven Cu concentrations (0, 25, 50, 100, 150, 200, and 300 mg kg-1 soil) for 12 weeks. The morphological (i.e. growth) and biochemical (i.e. chlorophyll) parameters of both the plant species were observed throughout the experimental period; the phytoextraction efficiency of S. indicum and C. tetragonoloba were also determined. Most growth parameters were reduced under high Cu stress. Our results shows that at low concentration (25 mg Cu kg-1) all the growth and biochemical parameters were increased but at elevated Cu concentrations, root length, shoot length, and biomass (fresh and dry) were all significantly decreased ( p soil was noted for all tested treatments. In this study, both plant species showed quite high Cu tolerance and accumulation efficiency, even though C. tetragonoloba have higher Cu accumulation and tolerance indices than that of S . indicum. At 300 mg Cu kg-1, the highest Cu concentration was found in the root (282.08 mg Cu kg-1) followed by leaf (105.78 mg Cu kg-1), stem (65.30 mg Cu kg-1), and pod (8.13 mg Cu kg-1) of S. indicum. In contrast, C. tetragonoloba had highest Cu concentration primarily in the root (158.45 mg Cu kg-1) followed by the stem (154.73 mg Cu kg-1), leaf (152.32 mg Cu kg-1), and pod (8.13 mg Cu kg-1). Considering rapid growth, high biomass, tolerance, accumulation efficiency, bioconcentration factor (BCF) > 1, bioaccumulation coefficient (BAC) > 1 and translocation factor (TF) > 1 established C. tetragonoloba as a potential candidate plant for the decontamination of slightly Cu-polluted soil where the growth of plants would not be impaired and the extraction of Cu could

Reliefs the Exposure Stress of Soils Arsenic on Brassica campestris L. Growth and Its Possible Mechanisms by Inoculation of Trichoderma asperellum SM-12F1

Directory of Open Access Journals (Sweden)

ZHANG Hong-xiang

2018-02-01

Full Text Available The over-accumulation of arsenic(Asin agricultural soils affects crop growth. Subsequently, the accumulated As can pose risk to human health via food-chain. It is urgent to develop technologies to relief the As exposure stress on crop growth and lower the As uptake by crop. In this study, Trichoderma asperellum SM -12F1, capable of As resistance and speciation transformation was used as experimental material. Pot experiments were conducted to investigate the effects of inoculation on the growth of Brassica campestris L. in As-contaminated soils. The possible mechanisms of inoculation relieving As exposure stress and lowering As uptake were revealed. The results indicated that the growth of Brassica campestris L. was significantly inhibited in soils spiked with As of 120 mg· kg-1. Inoculation could significantly improve the growth of Brassica campestris L. and significantly decreased the As uptake and bioconcentration factor(BCFof Brassica campestris L. Compared with As-contaminated soils without inoculation, the As contents in the over-and under-ground part of Brassica campestris L. declined by 12.4% and 20.2%, respectively, and the BCF declined by 7.8%. Soil available As contents decreased by 15.7% after inoculation. Methylarsonic acid(MMAand dimethylarsinic acid(DMAwere detected in water extraction of soil and the shoot of Brassica campestris L. tissues, which indicated that inoculation could trigger soil As methylation and decrease soil As availability and toxicity. Furthermore, inoculation could effectively relief the As exposure stress on Brassica campestris L. growth by the response of antioxidant enzymes. The enzymes in Brassica campestris L. such as superoxide dismutase(SODand catalase(CAT, and the contents of glutathione(GSH, ascorbic acid(AsAand malondialdehyde(MDA, capable of reactive oxygen elimination, significantly enhanced during soil As exposure. However, inoculation lessened the activities or contents of SOD, CAT, GSH, and MDA

Bioremediation of arsenic (As from mine effluent by a horizontal flow constructed wetland: A case study in largest borax reserve area in over the world, Kırka, Eskişehir

Directory of Open Access Journals (Sweden)

Onur Can Türker

2016-12-01

Full Text Available In this study, a horizontal flow constructed wetland (HFCW planted with Typha angustifolia, was tested to bioremediation potential for arsenic from mine effluent under the natural climatic conditions in largest boron mine reserve area over the world, Kırka (Eskişehir. Briefly, the objective of the present experiment was to investigate arsenic bioremediation capability of wetland system and asses the phytoremediation efficiency of T. angustifolia, selected as a donor plant in this study, with different initial arsenic concentrations. Our results indicated that HFCW has capability to decreased arsenic in mine effluent from 49 µg L-1 to 21.8 µg L-1 in a period of 84 days, suggesting that HFCW could be a reasonable bio-filter option to control arsenic pollution directly from mining effluent in largest borax reserve over the world. Furthermore, we found that arsenic concentration in outflow samples was stably below 10 µg L-1 (drinking water safety limit with an inflow range from 42.3 to 42.1 arsenic µg L-1 during the first 28 days. Our results also indicated that belowground parts of T.angustifolia accumulate more arsenic from mine effluent compared to aboveground parts during experiment period. Therefore, we suggested that belowground parts of the plants in HFCW play an important role for arsenic bioremediation from mine effluent which origin of Kırka Borax reserve area. In this respect, bioconcentration factor (BCF for the plants which grown in HFCW was found higher than those of control group. Moreover, results of the present experiment also showed that relatively high level of arsenic retained in the filtration media of HFCW during the experiment period, indicating that filtration media which was used in HFCW has potential to filter arsenic from mine effluent. Consequently, the scientific insight of the present study is to present an innovative, cost effective, and easy operating method for arsenic remediation from mine effluent.

Pentachlorophenol (PCP) bioaccumulation and effect on heat production on salmon eggs at different stages of development

Energy Technology Data Exchange (ETDEWEB)

Maeenpaeae, Kimmo A.; Penttinen, Olli-Pekka; Kukkonen, Jussi V.K

2004-05-28

In this study, pentachlorophenol (PCP) bioaccumulation and its effect on heat dissipation was studied in eggs of the lake salmon (Salmo salar m. sebago). In bioaccumulation studies, the eggs were exposed to low concentrations (0.051-0.056 {mu}mol/l, 13.583-14.915) of waterborne [{sup 14}C]-labeled PCP at two developmental stages: (1) 3 weeks after fertilization, and (2) just before hatching. The effect of PCP on egg heat dissipation was measured by a microcalorimeter after exposing the eggs to gradual concentrations (0-0.992 {mu}mol/l) of PCP for 48 h. After both the bioaccumulation and heat dissipation experiments, the eggs were dissected and the concentrations of PCP in tissue were determined separately for eggshell, yolk and embryo. The bioaccumulation studies showed that PCP accumulates more in the eggs at the late developmental stage. Bioconcentration factors (BCF) for different tissues were 3-42 times higher for the eggs at the late developmental stage compared with the eggs that were incubated only for 3 weeks. In early developmental stage, the eggshell adsorbs a large portion of the chemical. In late developmental stage, the actual embryo accumulated both proportionately and totally more than other dissected tissues in the beginning of the exposure, but eventually the yolk accumulated highest total amount of the chemical. A probable reason for the higher PCP body burden in the late developmental stage is that the respiration rate and metabolic activity of the embryo increases as it grows. The salmon eggs responded to an exposure to PCP with an elevated rate of heat dissipation. The threshold concentration above which the embryo heat dissipation was amplified was 29.64 {mu}mol/kg embryo wet weight (ww) or 0.28 {mu}mol/l. The highest embryo heat production was measured at the exposure concentration of 0.992 {mu}mol/l. At higher exposure concentrations the heat dissipation decreased. The basic findings of the study are that PCP accumulates in growing embryonic

Is it photosensitization or photodegradation when UV-B irradiation is combined with BDE-47? Evidence from the growth and reproduction changes of rotifer Brachionus plicatilis.

Science.gov (United States)

Liu, Chunchen; Tang, Xuexi; Zhou, Bin; Jiang, Yongshun; Lv, Mengchen; Zang, Yu; Wang, You

2018-07-01

Ecotoxicological methods were applied in the present study, and the marine rotifer Brachionus plicatilis was used as the toxic endpoint to depict what occurred when 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) was combined with solar ultraviolet-B radiation (UV-B). B. plicatilis was exposed to three different combination methods of BDE-47 and UV-B at an equal toxicity ratio, including normal rotifer co-cultured with UV-B-irradiated BDE-47 (known as Method I), UV-B-irradiated rotifer co-cultured with BDE-47 exposure (known as Method II) and normal rotifer co-cultured with the simultaneous addition of BDE-47 and UV-B irradiation (known as Method III). Acute and chronic experiments were preformed to determine the toxicity differentiation according to the growth and reproduction changes in the rotifer. Twenty-four-hour acute experiments showed that the modes of three combined methods changed from antagonism to additive, to synergistic with the concentration/dose increment, and the contribution rates of Method I and Method II to Method III were calculated by approximately 40.4% and 59.6%, respectively. Chronic exposure to either the single stressor or the combination of stressors inhibited the growth and reproduction of the rotifer, demonstrating the inhibition of the population growth rate and the decrease in the larvae production. Three combined groups presented more serious damages compared to groups with single stress exposure, and the ascending sequence of toxicity was Method Ibioconcentration factor (BCF) general ranked Method II

Uptake of radionuclide thorium by twelve native plants grown in uranium mill tailings soils from south part of China

International Nuclear Information System (INIS)

Yan, Xun

2016-01-01

Highlights: • Screen dominant plants grown in uranium mill tailings soils. • Quantify the content of "2"3"2Th of soil samples from uranium mill tailings. • Quantify the transfer factor, bioconcentration factor and phytoremediation factor. • Screen out the plant species capable of remediating radionuclide contaminated soils. • Guide the reuse of study area in future. - Abstract: The concentrations of thorium ("2"3"2Th) in soil from a uranium mill tailings repository in South China were analyzed. The results showed that all the soil samples were acidic and the concentrations of "2"3"2Th in all the soil samples were more than the natural radionuclide content in soil of China. Through the field investigation, twelve kinds of dominant plants were discovered. The total quantity of "2"3"2Th in the whole plant is highest in rice flat sedge. We also found that Miscanthus floridulus has the greatest transfer factor (TF) for "2"3"2Th, rice flat sedge has the greatest bioconcentration factor (BF) for "2"3"2Th. At the mean time, M. floridulus has the greatest phytoremediation factor (PF) for "2"3"2Th. On the basis of the above conclusions and the definition for hyperaccumulator, rice flat sedge and M. floridulus could be the candidates of phytoremediation for radionuclide "2"3"2Th in the soil.

Uptake of radionuclide thorium by twelve native plants grown in uranium mill tailings soils from south part of China

Energy Technology Data Exchange (ETDEWEB)

Yan, Xun, E-mail: m13836295186@163.com

2016-08-01

Highlights: • Screen dominant plants grown in uranium mill tailings soils. • Quantify the content of {sup 232}Th of soil samples from uranium mill tailings. • Quantify the transfer factor, bioconcentration factor and phytoremediation factor. • Screen out the plant species capable of remediating radionuclide contaminated soils. • Guide the reuse of study area in future. - Abstract: The concentrations of thorium ({sup 232}Th) in soil from a uranium mill tailings repository in South China were analyzed. The results showed that all the soil samples were acidic and the concentrations of {sup 232}Th in all the soil samples were more than the natural radionuclide content in soil of China. Through the field investigation, twelve kinds of dominant plants were discovered. The total quantity of {sup 232}Th in the whole plant is highest in rice flat sedge. We also found that Miscanthus floridulus has the greatest transfer factor (TF) for {sup 232}Th, rice flat sedge has the greatest bioconcentration factor (BF) for {sup 232}Th. At the mean time, M. floridulus has the greatest phytoremediation factor (PF) for {sup 232}Th. On the basis of the above conclusions and the definition for hyperaccumulator, rice flat sedge and M. floridulus could be the candidates of phytoremediation for radionuclide {sup 232}Th in the soil.

Field based investigation on phytoremediation potentials of Lemna minor and Azolla filiculoides in tropical, semiarid regions: Case of Ethiopia.

Science.gov (United States)

Amare, Elfu; Kebede, Fassil; Berihu, Tesfay; Mulat, Worku

2017-10-16

This study investigated the concurrent accumulation of eight heavy metals by two floating aquatic macrophytes (Lemna minor and Azolla filiculoides) cultivated in ambient media and blended wastewaters in the semiarid regions of Ethiopia. Both species accumulated heavy metals in varying degrees with a significant concentration gradient within the immediate water media. Highest bioconcentration factor was determined for Mn and Fe in both plants. Results revealed that L. minor was high phytoaccumulator for Fe, Mn, Zn and Co but moderate for Cd, Cu, Ni and Cr. On the other hand, A. filiculoides was a high accumulator for Fe, Mn, Zn and Cu, but its potency was moderate for Co, Cr and Ni, but lower for Cd. Both species exhibited significant difference in accumulating Co, Zn and Mn (p < 0.05). In general, the bioconcentration factors for both plants were comparable within the same treatment. In this study, stronger associations between the heavy metal concentrations in the plant tissues and in the grown water media were observed for A. filiculoides.

A Dual-Phase Ceramic Membrane with Extremely High H2 Permeation Flux Prepared by Autoseparation of a Ceramic Precursor.

Science.gov (United States)

Cheng, Shunfan; Wang, Yanjie; Zhuang, Libin; Xue, Jian; Wei, Yanying; Feldhoff, Armin; Caro, Jürgen; Wang, Haihui

2016-08-26

A novel concept for the preparation of multiphase composite ceramics based on demixing of a single ceramic precursor has been developed and used for the synthesis of a dual-phase H2 -permeable ceramic membrane. The precursor BaCe0.5 Fe0.5 O3-δ decomposes on calcination at 1370 °C for 10 h into two thermodynamically stable oxides with perovskite structures: the cerium-rich oxide BaCe0.85 Fe0.15 O3-δ (BCF8515) and the iron-rich oxide BaCe0.15 Fe0.85 O3-δ (BCF1585), 50 mol % each. In the resulting dual-phase material, the orthorhombic perovskite BCF8515 acts as the main proton conductor and the cubic perovskite BCF1585 as the main electron conductor. The dual-phase membrane shows an extremely high H2 permeation flux of 0.76 mL min(-1)  cm(-2) at 950 °C with 1.0 mm thickness. This auto-demixing concept should be applicable to the synthesis of other ionic-electronic conducting ceramics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Antioxidant, Anti-Inflammatory and Anti-Apoptotic Activities of the Bauhinia Championii Flavone are Connected with Protection Against Myocardial Ischemia/Reperfusion Injury.

Science.gov (United States)

Jian, Jie; Xuan, Feifei; Qin, Feizhang; Huang, Renbin

2016-01-01

Previous studies have demonstrated that Bauhinia championii flavone (BCF) exhibits anti-oxidative, anti-hypoxic and anti-stress properties. This study was designed to investigate whether BCF has a cardioprotective effect against myocardial ischemia/reperfusion (I/R) injuries in rats and to shed light on its possible mechanism. The model of I/R was established by ligating the left anterior descending coronary artery for 30 min, then reperfusing for 180 min. Hemodynamic changes were continuously monitored. The content of malondialdehyde (MDA) as well as the lactate dehydrogenase (LDH), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were assessed. The release of interleukin-6 (IL-6) was measured by enzyme-linked immunosorbent assay (ELISA). Apoptosis of cardiomyocytes was determined by caspase-3 activity and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. The expression of TLR4, NF-x03BA;Bp65, Bcl-2 and Bax were detected by western blotting. Pretreatment with BCF significantly reduced the serum levels of LDH, MDA and IL-6, but increased the activities of SOD and GSH-Px. It also attenuated myocardial infarct size, reduced the apoptosis rate and preserved cardiac function. Furthermore, BCF inhibited caspase-3 activity and the expression of TLR4, phosphorylated NF-x03BA;Bp65 and Bax, but enhanced the expression of Bcl-2. These results provide substantial evidence that BCF exerts a protective effect on myocardial I/R injury, which may be attributed to attenuating lipid peroxidation, the inflammatory response and apoptosis. © 2016 The Author(s) Published by S. Karger AG, Basel.

Metals and organotins in multiple bivalve species in a one-off global survey

DEFF Research Database (Denmark)

Larsen, Martin Mørk; Strand, Jakob; Christensen, Jan H.

2011-01-01

contamination levels on a global scale. Metal concentrations in nine bivalve species were normalised to the Mytilidae family using conversion factors based on cosampled species and literature bioconcentration factors. The lowest metal and tributyltin concentrations were below background assessment...... were low, but not always lower than expected impacted areas. The most contaminated areas were harbours, where especially Copenhagen, St Croix and Sydney, can be considered hotspots of tributyltin as well as a number of metals....

Arsenic contamination in irrigation water, agricultural soil and maize crop from an abandoned smelter site in Matehuala, Mexico.

Science.gov (United States)

Ruíz-Huerta, Esther Aurora; de la Garza Varela, Alonso; Gómez-Bernal, Juan Miguel; Castillo, Francisco; Avalos-Borja, Miguel; SenGupta, Bhaskar; Martínez-Villegas, Nadia

2017-10-05

Mobility of Arsenic (As) from metallurgical wastes in Matehuala, Mexico has been accounted for ultra-high concentration of As in water (4.8-158mg/L) that is used for recreational purposes as well as cultivation of maize. In this study, we (i) measured As concentrations in soils irrigated with this water, (ii) investigated the geochemical controls of available As, and (iii) measured bioaccumulation of As in maize. Water, soil, and maize plant samples were collected from 3 different plots to determine As in environmental matrices as well as water soluble As in soils. Soil mineralogy was determined by X-ray diffraction analysis. Bioaccumulation of As in maize plants was estimated from the bioconcentration and translocation factors. We recorded As built-up in agricultural soils to the extent of 172mg/kg, and noted that this As is highly soluble in water (30% on average). Maize crops presented high bioaccumulation, up to 2.5 times of bioconcentration and 45% of translocation. Furthermore, we found that water extractable As was higher in soils rich in calcite, while it was lower in soils containing high levels of gypsum, but As bioconcentration showed opposite trend. Results from this study show that irrigation with As rich water represents a significant risk to the population consuming contaminated crops. Copyright © 2017 Elsevier B.V. All rights reserved.

Integrative assessment of biomarker responses in teleostean fishes exposed to glyphosate-based herbicide (Excel Mera 71

Directory of Open Access Journals (Sweden)

Sukhendu Dey

2016-12-01

Full Text Available Present study deals with the effects of glyphosate-based herbicide, Excel Mera 71 on Anabas testudineus, Heteropnestes fossilis and Oreochromis niloticus in field conditions (1.85 kg/ha based on anti-oxidative, metabolic and digestive responses. For this study following biomarkers viz., acetylcholinesterase (AChE, lipid peroxidation (LPO, catalase (CAT, glutathione-S-transferase (GST, alkaline phosphatase (ALP, aspartate aminotransferase (AST, alanine aminotransferase (ALT, amylase, lipase and protease were investigated in gill, stomach, intestine, liver, kidney, brain, muscle and spinal cord of the concerned fish species. Enzyme activities were significantly altered by glyphosate exposure after 30 days, these activities were tissue as well as species specific. The results suggested that these biomarkers could be used to assess the ecological risks of glyphosate on fish. Bioaccumulation factor (BAF studied in different aquatic natural macrophytes showed order of Alternanthera philoxeroides > Azolla pinnata > Lemna sp. (Minor > Lemna sp. (Major > Pistia stratiotes, while transfer factor (TF showed the order of Pistia stratiotes > Alternanthera philoxeroides > Lemna sp. Bioconcentration factor (BCF study showed maximum accumulation of glyphosate in liver, kidney or intestine, and minimum either in bone or stomach irrespective of fish species. An integrated biomarker response (IBR, which uses a battery of biomarkers to calculate the standardized scores for each biomarker responses ranging from physiological to biochemical/molecular responses, was evaluated by combining the multiple biomarkers into a single value to evaluate quantitatively the toxicological effects of glyphosate. In general, the multiple indices exhibited variations and A. testudineus was more affected than other fish species; maximum IBR value was observed for LPO and minimum in case of ALT. The order of integrated biomarkers caused by glyphosate treatment was

Natural gas imports and exports. First quarter report 1994

Energy Technology Data Exchange (ETDEWEB)

1994-08-01

The Office of Fuels Programs Prepares quarterly reports Summarizing the data provided by companies authorized to import or export natural gas. Companies are required, as a condition of their authorizations, to file quarterly reports with the OFP. This report is for the first quarter of 1994 (January--March). Attachment A shows the percentage of takes to maximum firm contract levels and the weighted average per unit price for each of the long-term importers during the five most recent reporting quarters. Attachment B shows volumes and prices of gas purchased by long-term importers and exporters during the past twelve months. Attachment C shows volume and price information for gas imported on a short-term basis. Attachment D shows the gas exported on a short-term basis to Canada and Mexico. During the first three months of 1994, data indicates that gas imports grew by about 14 percent over the level of the first quarter of 1993 (668 vs. 586 Bcf), with Canadian and Algerian imports increasing by 12 and 53 percent, respectively. During the same time period, exports declined by 15 percent (41 vs. 48 Bcf). Exports to Canada increased by 10 percent from the 1993 level (22 vs. 20 Bcf) and exports to Mexico decreased by 64 percent (5 vs. 14 Bcf).

Natural gas imports and exports; Fourth quarterly report, 1993

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-12-31

The Office of Fuels Programs prepares quarterly reports summarizing the data provided by companies authorized to import or export natural gas. Companies are required, as a condition of their authorizations, to file quarterly reports with the OFP. This report is for the fourth quarter of 1993 (October--December). Attachment A shows the percentage of takes to maximum firm contract levels and the weighted average per unit price for each of the long-term importers during the 5 most recent reporting quarters. Attachment B shows volumes and prices of gas purchased by long-term importers and exporters during the past 12 months. Attachment C shows volume and price information for gas imported on a short-term basis. Attachment D shows the gas exported on a short-term basis to Canada and Mexico. During 1993, data indicates gas imports grew by about 10 percent over the 1992 level (2328 vs. 2122 Bcf), with Canadian and Algerian imports increasing by 8 and 82 percent, respectively. During the same time period, exports declined by 41 percent (144 vs. 243 Bcf). Exports to Canada decreased 47 percent from the 1992 level (50 vs. 95 Bcf) and exports to Mexico decreased by 60 percent (38 vs. 95 Bcf).

Absorption of Mercury from Polluted Soil by Rice Plant(Case Study: Farms of Amol Industrial Suburban Area

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Fatemeh Ahmadipour

2013-03-01

Full Text Available Mercury has recognized as one of the most toxic heavy metals, which many industries generate and dispose to the environment. Few studies are done about mercury accumulation in soil and bioconcentration and transfer factor of mercury in rice plant cultivated in industrial areas. In this study samples were taken randomly from 10 farms in vicinity of Amol industrial suburban area with three replications. Samples were measured by the LECO AMA 254 Advanced Mercury Analyzer according to ASTM D-6733method. Also the parameters related to the quality of the soil were measured. The mean of mercury concentration in soil, root, stem and grain were found 0.031 ±0.012 mg/kg, 0.074 ±0.0163 mg/kg, 0.058 ±0.008 mg/kg and 0.051 ±0.0083 mg/kg respectively. The calculated transfer factor of mercury to various organs and bioconcentration factor were < 1 and 2.46 respectively. Pearson correlation test showed a positive correlation between mercury concentration in soil with mercury concentration in grain and also a negative correlation between pH with mercury concentration in root and soil. It is concluded that rice plant have high potential for phytoremediation of mercury from soil.

Heavy Metals Accumulation Characteristics of Vegetables in Hangzhou City, China

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GU Yan-qing

2015-08-01

Full Text Available A field survey of heavy metal concentrations in soils and vegetables grown in 30 vegetable farmlands of Hangzhou City were carried out. Through calculating the bioconcentration factor(BCFand transfer factor(TFfor different heavy metals(Cu, Zn, Cd, Cr and Pbin 27 kinds of different vegetables which belong to leafy vegetables, root vegetables or eggplant fruit vegetables, assessing their accumulation characteristics of heavy metals according to the differences of the bio-concentration factor, the reasonable proposals were put forward to optimize the planting structure of vegetables in mild and middle-level heavy metal contamination soils. The experimental results were as follows: In soils with mild and middle-level heavy metal contamination, leafy vegetables, such as crown daisy, cabbage, celery and Chinese long cabbage, had relatively low enrichment ability of heavy metals, so as the root and fruit vegetables like white radish, carrot, tomatoes, hence these vegetables could be planted preferentially. In contrast, some kinds of vegetables, including white amaranth, red amaranth, tatsoi, broccoli, gynura, brassica juncea and lettuce of leafy vegetables, lactuca sativa, taro, red radish and cherry radish of rhizome vegetables and sweet pepper of fruit vegetables, had relatively high accumulation ability of heavy metal, which should be avoided to be planted in soils with mild and middle-level heavy metal contamination.

Trace Elements in Dominant Species of the Fenghe River, China: Their Relations to Environmental Factors.

Science.gov (United States)

Yang, Yang; Zhou, Zhengchao; Bai, Yanying; Jiao, Wentao; Chen, Weiping

2016-07-01

The distribution of trace elements (TEs) in water, sediment, riparian soil and dominant plants was investigated in the Fenghe River, Northwestern China. The Fenghe River ecosystem was polluted with Cd, Cr, Hg and Pb. There was a high pollution risk in the midstream and downstream regions and the risk level for Cd was much higher than that of the other elements. The average values of bioconcentration coefficient for Cd and Zn were 2.21 and 1.75, respectively, indicating a large accumulation of Cd and Zn in the studied species. With broad ecological amplitudes, L. Levl. et Vant. Trin., and L. had the greatest TE concentrations in aboveground and belowground biomass of the studied species and were potential biomonitors or phytoremediators for the study area. Multivariate techniques including cluster analysis, correlation analysis, principal component analysis, and canonical correspondence analysis were used to analyze the relations between TE concentrations in plants and various environmental factors. The soil element concentration is the main factor determining the accumulation of TEs in plants. The co-release behavior of common pollutants and TEs drove the accumulation of Hg, Cd, and As in the studied plants. Significant enrichment of some elements in the Fenghe River has led to a decline in the biodiversity of plants. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Findings on the phytoextraction and phytostabilization of soils contaminated with heavy metals.

Science.gov (United States)

Cheraghi, M; Lorestani, B; Khorasani, N; Yousefi, N; Karami, M

2011-12-01

As a result of human activities such as mining, metal pollution has become one of the most serious environmental problems today. Phytoremediation, an emerging cost-effective, non-intrusive, and aesthetically pleasing technology that uses the remarkable ability of plants to concentrate elements can be potentially used to remediate metal-contaminated sites. The aim of this work was to assess the extent of metal accumulation by plants found in a mining area in Hamedan province with the ultimate goal of finding suitable plants for phytoextraction and phytostabilization (two processes of phytoremediation). To this purpose, shoots and roots of the 12 plant species and the associated soil samples were collected and analyzed by measurement of total concentrations of some elements (Fe, Mn, Zn, and Cu) using atomic absorption spectrophotometer and then biological absorption coefficient, bioconcentration factor, and translocation factor parameters calculated for each element. Our results showed that none of the plants were suitable for phytoextraction and phytostabilization of Fe, Zn, and Cu, while Chenopodium botrys, Stipa barbata, Cousinia bijarensis, Scariola orientalis, Chondrila juncea, and Verbascum speciosum, with a high biological absorption coefficient for Mn, were suitable for phytoextraction of Mn, and C. bijarensis, C. juncea, V. speciosum, S. orientalis, C. botrys, and S. barbata, with a high bioconcentration factor and low translocation factor for Mn, had the potential for the phytostabilization of this element.

Manganese, nickel and strontium bioaccumulation in the tissues of the African sharptooth catfish, Clarias gariepinus from the Olifants River, Kruger National Park

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Annemarie Avenant-Oldewage

2000-07-01

Full Text Available The gills, liver, muscle and skin were collected from Clarias gariepinus, during four surveys (February, May, June and November in 1994 from two sites on the Olifants River in the Kruger National Park. With the use of atomic absorption spectrophotometry, metal concentrations of manganese, nickel and strontium bioaccumulated in these tissues were determined. This information was then used to differentiate between the concentrations found at the two locations and between the four survey periods. The con- centration of the metals were found to be highest in the gills, followed by the liver. This suggests the gills to be the primary uptake tissue for these metals following their intimate blood-water contact. The concentration of manganese and strontium, with particular reference to the gills, showed highest bioaccumulation at Mamba. Very little differences in the nickel concentrations were found at both Mamba and Balule. Water bioconcentration factors for manganese and nickel were much higher than that noted for sediment, suggesting a much lower bioavailability of these metals from the sediment. On the other hand, sediment bioconcentration factors for strontium were generally higher than that for water, which could imply higher bioavailability and concentration from the sediment.

The Effect of Lifting Speed on Cumulative and Peak Biomechanical Loading for Symmetric Lifting Tasks

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Kasey O. Greenland

2013-06-01

Conclusion: Based on peak values, BCF is highest for fast speeds, but the BCF cumulative loading is highest for slow speeds, with the largest difference between fast and slow lifts. This may imply that a slow lifting speed is at least as hazardous as a fast lifting speed. It is important to consider the duration of lift when determining risks for back and shoulder injuries due to lifting and that peak values alone are likely not sufficient.

Multi-scale cellulose based new bio-aerogel composites with thermal super-insulating and tunable mechanical properties.

Science.gov (United States)

Seantier, Bastien; Bendahou, Dounia; Bendahou, Abdelkader; Grohens, Yves; Kaddami, Hamid

2016-03-15

Bio-composite aerogels based on bleached cellulose fibers (BCF) and cellulose nanoparticles having various morphological and physico-chemical characteristics are prepared by a freeze-drying technique and characterized. The various composite aerogels obtained were compared to a BCF aerogel used as the reference. Severe changes in the material morphology were observed by SEM and AFM due to a variation of the cellulose nanoparticle properties such as the aspect ratio, the crystalline index and the surface charge density. BCF fibers form a 3D network and they are surrounded by the cellulose nanoparticle thin films inducing a significant reduction of the size of the pores in comparison with a neat BCF based aerogel. BET analyses confirm the appearance of a new organization structure with pores of nanometric sizes. As a consequence, a decrease of the thermal conductivities is observed from 28mWm(-1)K(-1) (BCF aerogel) to 23mWm(-1)K(-1) (bio-composite aerogel), which is below the air conductivity (25mWm(-1)K(-1)). This improvement of the insulation properties for composite materials is more pronounced for aerogels based on cellulose nanoparticles having a low crystalline index and high surface charge (NFC-2h). The significant improvement of their insulation properties allows the bio-composite aerogels to enter the super-insulating materials family. The characteristics of cellulose nanoparticles also influence the mechanical properties of the bio-composite aerogels. A significant improvement of the mechanical properties under compression is obtained by self-organization, yielding a multi-scale architecture of the cellulose nanoparticles in the bio-composite aerogels. In this case, the mechanical property is more dependent on the morphology of the composite aerogel rather than the intrinsic characteristics of the cellulose nanoparticles. Copyright © 2015 Elsevier Ltd. All rights reserved.

Influences of binding to dissolved organic matter on hydrophobic organic compounds in a multi-contaminant system: Coefficients, mechanisms and ecological risks.

Science.gov (United States)

Li, Yi-Long; He, Wei; Liu, Wen-Xiu; Kong, Xiang-Zhen; Yang, Bin; Yang, Chen; Xu, Fu-Liu

2015-11-01

The complexation flocculation (CF) method was successfully employed to identify binding coefficients (Kdoc) of specific organic contaminants to dissolved organic matter (DOM, often indicated by dissolved organic carbon, DOC) in a multi-contaminant hydrophobic organic contaminant (HOC) system. Kdoc values were obtained for most of the evaluated 33 HOCs, indicating the feasibility and applicability of the CF method in a multi-contaminant system. Significant positive correlations were observed between binding coefficients and octanol-water partition coefficients (Kow) for organic halogen compounds, such as polybrominated diphenyl ethers (PBDEs) (R(2) = 0.95, p mechanisms between PAHs and organic halogen compounds exist. These differences further result in discriminative competition partitions of HOCs between DOM and organisms. Assuming that only freely dissolved HOCs are bioconcentrative, the results of DOM-influenced bioconcentration factor (BCFDOM) and DOM-influenced lowest observed effect level (LOELDOM) indicate that the ecological risk of HOCs is decreased by DOM. Copyright © 2015 Elsevier Ltd. All rights reserved.

Environmental behavior and impact assessment of radioactive materials

International Nuclear Information System (INIS)

Lee, S.R.; Ryu, B.S.; Kim, K.C.; Lee, G.J.; Shim, A.R.; Park, H.K.

1982-01-01

It was studied to investigate the bioconcentration processes of strontium-90 in aquatic and terrestrial plants. The concentration and retention of strontium-90 from seawater by the seaweed Undaria pinnatifida varied depending on the plant part, exposure time, radionuclide concentration, salinity, contents of stable calcium and strontium, and presence of chelating agent in the seawater. The concentration factors attained at equilibrium were in the range of 50, and it was evident that the bioconcentration was largely due to the adsorption of the radionuclide on the surface of seaweed. In the foliar application of strontium-90 to a terrestrial plant soybean, Glycine max, only a portion of the radioactivity was translocated to other parts, and most of it remained in the applied leaves, causing soil contamination by falling. In the soil application of strontium-90 during the growth period of the plant, the radioactivity was absorbed through the root and translocated to other parts by different patterns according to the growth stage. (Author)

Bioavailability of heavy metals, germanium and rare earth elements at Davidschacht dump-field in mine affected area of Freiberg (Saxony)

Science.gov (United States)

Midula, Pavol; Wiche, Oliver

2016-04-01

Bioavailability research presents an essential tool, in modern phytoremediation and phytomining technologies, allowing the estimation of plant available fractions of elements in soils. However, up to date, sufficient interdisciplinary knowledge on the biogeochemically impacted behavior of specific target elements, in particular Ge and REEs in mining affected soils and their uptake into strategically used plants is lacking. This presented work is focused on a correlation study between the concentrations of selected heavy metals, Ge and REEs in soils formed on the top of the dump-field of Davidschacht and the corresponding their concentrations in 12 vascular plant species. The mine-dump of Davidschacht, situated in the Freiberg (Saxony, Germany) municipality area was chosen as the study area, which has been considered to be a high contaminated enclave, due to the mining history of the region. In total 12 sampling sites with differing composition of plant species were selected. At each sampling site soil samples from a soil depth of 0 - 10 cm and samples of plant material (shoots) were taken. The soil samples were analysed for total concentration of elements, pH (H2O) and consequently analysed by 4-step sequential extraction (SE) to determine fractions of elements that are mobile (fraction 1), acid soluble (pH 5) (fraction 2), bound to organic and oxidizable matter (fraction 3) and bound to amorphic oxides (fraction 4). The plant material was decomposed by hydrofluoric acid in order to extract the elements. Concentrations of elements in soil extracts and digestion solutions were analysed by ICP-MS. For all species bioconcentration factor (BCF) was calculated of the total concentration of elements in order to investigate the bioaccumulation potential. Arsenic (As), cadmium (Cd) and lead (Pb) were chosen as the representative heavy metals. Within the REEs neodymium (Nd) and cerium (Ce) were selected as representatives for all REEs, since Nd and Ce correlated significant

Occurrence of perchloroethylene in surface water and fish in a river ecosystem affected by groundwater contamination.

Science.gov (United States)

Wittlingerová, Zdena; Macháčková, Jiřina; Petruželková, Anna; Zimová, Magdalena

2016-03-01

Long-term monitoring of the content of perchloroethylene (PCE) in a river ecosystem affected by groundwater contamination was performed at a site in the Czech Republic. The quality of surface water was monitored quarterly between 1994 and 2013, and fish were collected from the affected ecosystem to analyse the content of PCE in their tissue in 1998, 2011 and 2012. Concentrations of PCE (9-140 μg/kg) in the tissue of fish collected from the contaminated part of the river were elevated compared to the part of the river unaffected by the contamination (ND to 5 μg/kg PCE). The quality of surface water has improved as a result of groundwater remediation during the evaluated period. Before the remedial action, PCE concentrations ranged from 30 to 95 μg/L (1994-1997). Following commencement of remedial activities in September 1997, a decrease in the content of PCE in the surface water to 7.3 μg/L (1998) and further to 1 μg/L (2011) and 1.1 μg/L (2012) led to a progressive decrease in the average concentration of PCE in the fish muscle tissue from 79 μg/kg (1998) to 24 (2011) and 30 μg/kg (2012), respectively. It was determined that the bioconcentration of PCE does not have a linear dependence because the decrease in contamination in the fish muscle tissue is not directly proportional to the decrease in contamination in the river water. The observed average bioconcentration factors were 24 and 28 for the lower concentrations of PCE and 11 for the higher concentrations of PCE in the river. In terms of age, length and weight of the collected fish, weight had the greatest significance for bioconcentration, followed by the length, with age being evaluated as a less significant factor.

Ultra-Low Carbon Emissions from Coal-Fired Power Plants through Bio-Oil Co-Firing and Biochar Sequestration.

Science.gov (United States)

Dang, Qi; Mba Wright, Mark; Brown, Robert C

2015-12-15

This study investigates a novel strategy of reducing carbon emissions from coal-fired power plants through co-firing bio-oil and sequestering biochar in agricultural lands. The heavy end fraction of bio-oil recovered from corn stover fast pyrolysis is blended and co-fired with bituminous coal to form a bio-oil co-firing fuel (BCF). Life-cycle greenhouse gas (GHG) emissions per kWh electricity produced vary from 1.02 to 0.26 kg CO2-eq among different cases, with BCF heavy end fractions ranging from 10% to 60%, which corresponds to a GHG emissions reduction of 2.9% to 74.9% compared with that from traditional bituminous coal power plants. We found a heavy end fraction between 34.8% and 37.3% is required to meet the Clean Power Plan's emission regulation for new coal-fired power plants. The minimum electricity selling prices are predicted to increase from 8.8 to 14.9 cents/kWh, with heavy end fractions ranging from 30% to 60%. A minimum carbon price of $67.4 ± 13 per metric ton of CO2-eq was estimated to make BCF power commercially viable for the base case. These results suggest that BCF co-firing is an attractive pathway for clean power generation in existing power plants with a potential for significant reductions in carbon emissions.

Potential phytoextraction and phytostabilization of perennial peanut on copper-contaminated vineyard soils and copper mining waste.

Science.gov (United States)

Andreazza, Robson; Bortolon, Leandro; Pieniz, Simone; Giacometti, Marcelo; Roehrs, Dione D; Lambais, Mácio R; Camargo, Flávio A O

2011-12-01

This study sought to evaluate the potential of perennial peanut (Arachis pintoi) for copper phytoremediation in vineyard soils (Inceptisol and Mollisol) contaminated with copper and copper mining waste. Our results showed high phytomass production of perennial peanut in both vineyard soils. Macronutrient uptakes were not negatively affected by perennial peanut cultivated in all contaminated soils. Plants cultivated in Mollisol showed high copper concentrations in the roots and shoots of 475 and 52 mg kg(-1), respectively. Perennial peanut plants showed low translocation factor values for Cu, although these plants showed high bioaccumulation factor (BCF) for both vineyard soils, Inceptisol and Mollisol, with BCF values of 3.83 and 3.24, respectively, being characterized as a copper hyperaccumulator plant in these soils. Copper phytoextraction from Inceptisol soil was the highest for both roots and entire plant biomass, with more than 800 mg kg(-1) of copper in whole plant. The highest potential copper phytoextraction by perennial peanut was in Inceptisol soil with copper removal of 2,500 g ha(-1). Also, perennial peanut showed high potential for copper phytoremoval in copper mining waste and Mollisol with 1,700 and 1,500 g of copper per hectare, respectively. In addition, perennial peanuts characterized high potential for phytoextraction and phytostabilization of copper in vineyard soils and copper mining waste.

Genetic parameters for body weight ratio, fertility and growth traits in Canchim breed females

OpenAIRE

Silvio de Paula Mello; Maurício Mello de Alencar; Tiago Luciano Passafaro; Fabio Luiz Buranelo Toral

2013-01-01

The objective of this study was to estimate the heritability of age at first calving (AFC), body condition score at first calving (BCF), body condition score at calving (BCC), weaning weight (WW), yearling weight (W12), weaning weight of calf/weight of cow at calving (RCC) and weaning weight of first calf/weight of cow at first calving (RCCF) ratios, and genetic correlations of AFC, BCF, WW and W12 with RCCF, in a Canchim beef cattle herd. The variance and covariance components were obtained ...

Phytoremediation efficiency of pondweed (Potamogeton crispus in removing heavy metals (Cu, Cr, Pb, As and Cd from water of Anzali wetland

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Hajar Norouznia

2014-09-01

Full Text Available Plant-based remediation (i.e. phytoremediation is one of the most significant eco-sustainable techniques to cope with devastating consequences of pollutants. In the present study, the potential of a wetland macrophyt (i.e. Potamogeton crispus for the phytoremediation of heavy metals (i.e. Cu, Cr, Pb, As and Cd in the Anzali wetland was evaluated. The results showed that P. crispus tends to accumulate notable amounts of Cu, Cr, Pb, As and Cd according to their assayed concentrations as follows: 8.2 µg g-1 dw, 0.97 µg g-1 dw, 6.04 µg g-1 dw, 2.52 µg g-1 dw and 0.34 µg g-1 dw, respectively. Further accurate perception of the phytoremediation efficiency were conducted using both bioconcentration factor and translocation factor. The average of the highest bioconcentration factors was presented in a descending order as: 2.9×103, 1.9×103, 1.17×103, 0.68×103 and 0.46×103 for the Cu, Cr, Pb, Cd and As, respectively. Based on the results, P. crispus presents high potential to absorb all the alluded metals except for As and partly Cd. Correspondingly, the mean values of translocation factor were reported in the range of 0.41 to 2.24. Eventually, relying on the observed findings, the results support the idea that P. crispus species would be employed as the prospective candidate for the phytoremediation processes in Anzali wetland.

Seagull to acquire arkla exploration

International Nuclear Information System (INIS)

Anon.

1992-01-01

Seagull Energy Corp., Houston, has agreed to acquire Arkla Exploration Inc. from Arkla Inc., Shreveport, La., for about $402 million. The transaction-expected to net Seagull reserves totaling about 578 bcf of gas and 7.3 million bbl of oil and condensate-would more than double Seagull's proved reserves and nearly double its total assets. According to Seagull's 1991 annual report, the company's reserves at yearend 1991 were estimated at 401.2 bcf of gas equivalent (bcfe), including 335.1 bcf of gas and 11 million bbl of oil. Independent engineers at yearend 1991 estimated Arkla's proved reserves at 635 bcf of gas and 9 million bbl of liquids. Seagull Chairman Barry J. Galt said the company plans to keep many of Arkla Exploration's employees and to establish a meaningful presence in Shreveport. Arkla's already got good people in Shreveport and an operating base, a Seagull official said. We want to move in, put our name on the door, and continue the good operations Arkla already has. Seagull has lined up financing for the acquisition from a group of major U.S. banks. A new credit facility-consisting of a $475 million line of revolving credit and a $150 million 3 year term loan-will replace an exiting $225 million line of revolving credit. Boards of both companies have approved the deal, which Seagull and Arkla hope to close before yearend, subject to regulatory approvals and purchase price adjustments

Phytoremediation of cadmium and nickel by Spirodela polyrhiza

International Nuclear Information System (INIS)

Chaudhuri, Devaleena; Goswami, Chandrima; Chatterjee, Sumon; Majumder, Arunabha; Mishra, A.K.; Bandyopadhyay, Kaushik

2011-01-01

Heavy metal pollution in surface and groundwater has considerably increased in the last few years. It is essential to have an effective removal mechanism of these toxic metals. Current research includes the need to develop environment friendly and cost effective technologies for removing heavy metals from water. In several studies cadmium and nickel have been considerably removed using phytoremediation. The removal efficiency of cadmium and nickel by Spirodela polyrhiza, common duckweed has been examined in the present study for 3 different concentrations of cadmium (1, 2 and 3 mg/L) and nickel (4, 5 and 6 mg/L). Two sets of experiments for cadmium and nickel were conducted separately. Effect of metal toxicity on Spirodela polyrhiza was evaluated in terms of relative growth factor and cadmium was found to be more toxic than nickel. Under experimental condition BCF value for cadmium removal was more than >1000 in all the 3 concentrations of cadmium. But the BCF value was found to be more than > 1000 only when input nickel concentration was 4 mg/L during phytoremediation process. Experimental results suggest that Spirodela polyrhiza has the potential of accumulating cadmium and nickel from aqueous solution at lower metal concentration. (author)

Temperature variations as a source of uncertainty in medical fiber-coupled organic plastic scintillator dosimetry

DEFF Research Database (Denmark)

Buranurak, Siritorn; Andersen, Claus Erik; Beierholm, Anders Ravnsborg

2013-01-01

Fiber-coupled organic plastic scintillators have potential applications in medical dosimetry related to, for example, brachytherapy and external beam radiotherapy with MV photons. As medical dosimetry generally strives for high accuracy, we designed a study to assess if the light yield from...... commonly used scintillating fibers would change with temperature in the clinical range (15–40 °C). The study showed that the light yield in the peak regions of the scintillators studied decreases linearly with increasing temperature. For the blue BCF-12 and the green BCF-60 from Saint-Gobain, France we...

Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms

International Nuclear Information System (INIS)

Gonzalez-Barreiro, O.; Rioboo, C.; Herrero, C.; Cid, A.

2006-01-01

The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides

Removal of triazine herbicides from freshwater systems using photosynthetic microorganisms

Energy Technology Data Exchange (ETDEWEB)

Gonzalez-Barreiro, O. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Rioboo, C. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Herrero, C. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain); Cid, A. [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n. 15071 A Coruna (Spain)]. E-mail: cid@udc.es

2006-11-15

The uptake of the triazine herbicides, atrazine and terbutryn, was determined for two freshwater photosynthetic microorganisms, the green microalga Chlorella vulgaris and the cyanobacterium Synechococcus elongatus. An extremely rapid uptake of both pesticides was recorded, although uptake rate was lower for the cyanobacterium, mainly for atrazine. Other parameters related to the herbicide bioconcentration capacity of these microorganisms were also studied. Growth rate, biomass, and cell viability in cultures containing herbicide were clearly affected by herbicide uptake. Herbicide toxicity and microalgae sensitivity were used to determine the effectiveness of the bioconcentration process and the stability of herbicide removal. C. vulgaris showed higher bioconcentration capability for these two triazine herbicides than S. elongatus, especially with regard to terbutryn. This study supports the usefulness of such microorganisms, as a bioremediation technique in freshwater systems polluted with triazine herbicides.

Physiologically-based toxicokinetic models help identifying the key factors affecting contaminant uptake during flood events

International Nuclear Information System (INIS)

Brinkmann, Markus; Eichbaum, Kathrin; Kammann, Ulrike; Hudjetz, Sebastian; Cofalla, Catrina; Buchinger, Sebastian; Reifferscheid, Georg; Schüttrumpf, Holger; Preuss, Thomas

2014-01-01

Highlights: • A PBTK model for trout was coupled with a sediment equilibrium partitioning model. • The influence of physical exercise on pollutant uptake was studies using the model. • Physical exercise during flood events can increase the level of biliary metabolites. • Cardiac output and effective respiratory volume were identified as relevant factors. • These confounding factors need to be considered also for bioconcentration studies. - Abstract: As a consequence of global climate change, we will be likely facing an increasing frequency and intensity of flood events. Thus, the ecotoxicological relevance of sediment re-suspension is of growing concern. It is vital to understand contaminant uptake from suspended sediments and relate it to effects in aquatic biota. Here we report on a computational study that utilizes a physiologically based toxicokinetic model to predict uptake, metabolism and excretion of sediment-borne pyrene in rainbow trout (Oncorhynchus mykiss). To this end, data from two experimental studies were compared with the model predictions: (a) batch re-suspension experiments with constant concentration of suspended particulate matter at two different temperatures (12 and 24 °C), and (b) simulated flood events in an annular flume. The model predicted both the final concentrations and the kinetics of 1-hydroxypyrene secretion into the gall bladder of exposed rainbow trout well. We were able to show that exhaustive exercise during exposure in simulated flood events can lead to increased levels of biliary metabolites and identified cardiac output and effective respiratory volume as the two most important factors for contaminant uptake. The results of our study clearly demonstrate the relevance and the necessity to investigate uptake of contaminants from suspended sediments under realistic exposure scenarios

Physiologically-based toxicokinetic models help identifying the key factors affecting contaminant uptake during flood events

Energy Technology Data Exchange (ETDEWEB)

Brinkmann, Markus; Eichbaum, Kathrin [Department of Ecosystem Analysis, Institute for Environmental Research,ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Kammann, Ulrike [Thünen-Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Hudjetz, Sebastian [Department of Ecosystem Analysis, Institute for Environmental Research,ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Cofalla, Catrina [Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Buchinger, Sebastian; Reifferscheid, Georg [Federal Institute of Hydrology (BFG), Department G3: Biochemistry, Ecotoxicology, Am Mainzer Tor 1, 56068 Koblenz (Germany); Schüttrumpf, Holger [Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Preuss, Thomas [Department of Environmental Biology and Chemodynamics, Institute for Environmental Research,ABBt- Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); and others

2014-07-01

Highlights: • A PBTK model for trout was coupled with a sediment equilibrium partitioning model. • The influence of physical exercise on pollutant uptake was studies using the model. • Physical exercise during flood events can increase the level of biliary metabolites. • Cardiac output and effective respiratory volume were identified as relevant factors. • These confounding factors need to be considered also for bioconcentration studies. - Abstract: As a consequence of global climate change, we will be likely facing an increasing frequency and intensity of flood events. Thus, the ecotoxicological relevance of sediment re-suspension is of growing concern. It is vital to understand contaminant uptake from suspended sediments and relate it to effects in aquatic biota. Here we report on a computational study that utilizes a physiologically based toxicokinetic model to predict uptake, metabolism and excretion of sediment-borne pyrene in rainbow trout (Oncorhynchus mykiss). To this end, data from two experimental studies were compared with the model predictions: (a) batch re-suspension experiments with constant concentration of suspended particulate matter at two different temperatures (12 and 24 °C), and (b) simulated flood events in an annular flume. The model predicted both the final concentrations and the kinetics of 1-hydroxypyrene secretion into the gall bladder of exposed rainbow trout well. We were able to show that exhaustive exercise during exposure in simulated flood events can lead to increased levels of biliary metabolites and identified cardiac output and effective respiratory volume as the two most important factors for contaminant uptake. The results of our study clearly demonstrate the relevance and the necessity to investigate uptake of contaminants from suspended sediments under realistic exposure scenarios.

Ecotoxicity literature review of selected Hanford Site contaminants

International Nuclear Information System (INIS)

Driver, C.J.

1994-03-01

Available information on the toxicity, food chain transport, and bioconcentration of several Hanford Site contaminants were reviewed. The contaminants included cesium-137, cobalt-60, europium, nitrate, plutonium, strontium-90, technetium, tritium, uranium, and chromium (III and VI). Toxicity and mobility in both aquatic and terrestrial systems were considered. For aquatic systems, considerable information was available on the chemical and/or radiological toxicity of most of the contaminants in invertebrate animals and fish. Little information was available on aquatic macrophyte response to the contaminants. Terrestrial animals such as waterfowl and amphibians that have high exposure potential in aquatic systems were also largely unrepresented in the toxicity literature. The preponderance of toxicity data for terrestrial biota was for laboratory mammals. Bioconcentration factors and transfer coefficients were obtained for primary producers and consumers in representative aquatic and terrestrial systems; however, little data were available for upper trophic level transfer, particularly for terrestrial predators. Food chain transport and toxicity information for the contaminants were generally lacking for desert or sage brush-steppe organisms, particularly plants and reptiles

Genetic parameters for body weight ratio, fertility and growth traits in Canchim breed females

Directory of Open Access Journals (Sweden)

Silvio de Paula Mello

2013-03-01

Full Text Available The objective of this study was to estimate the heritability of age at first calving (AFC, body condition score at first calving (BCF, body condition score at calving (BCC, weaning weight (WW, yearling weight (W12, weaning weight of calf/weight of cow at calving (RCC and weaning weight of first calf/weight of cow at first calving (RCCF ratios, and genetic correlations of AFC, BCF, WW and W12 with RCCF, in a Canchim beef cattle herd. The variance and covariance components were obtained by bayesian inference with single and two-trait analyses. The statistical models included the additive direct and maternal, the permanent environmental and the residual random effects, and the fixed effects of year and month of birth or of calving, age of cow at calving and sex of calf, depending on the trait. The posterior means of heritability, obtained by single-trait analyses, were 0.12 (AFC, 0.36 (BCF, 0.18 (BCC, 0.50 (WW, 0.46 (W12, 0.16 (RCC and 0.40 (RCCF indicating that these traits have enough genetic variability to  show response to mass selection with the exception of AFC. The genetic correlations of AFC (-0.61, BCF (-0.36, WW (-0.20 and W12 (-0.05 with RCCF suggest that selection to reduce age and body condition score at first calving should improve the productivity trait of females at first calving, while selection for heavier females at young ages would not promote any change in the productivity of dams.

Transmission-enabled fiber Fabry-Perot cavity based on a deeply etched slotted micromirror.

Science.gov (United States)

Othman, Muhammad A; Sabry, Yasser M; Sadek, Mohamed; Nassar, Ismail M; Khalil, Diaa A

2018-06-01

In this work, we report the analysis, fabrication, and characterization of an optical cavity built using a Bragg-coated fiber (BCF) mirror and a metal-coated microelectromechanical systems (MEMS) slotted micromirror, where the latter allows transmission output from the cavity. Theoretical modeling, using Fourier optics analysis for the cavity response based on tracing the propagation of light back and forth between the mirrors, is presented. Detailed simulation analysis is carried out for the spectral response of the cavity under different design conditions. MEMS chips of the slotted micromirror are fabricated using deep reactive ion etching of a silicon-on-insulator substrate with different device-etching depths of 150 μm and 80 μm with aluminum and gold metal coating, respectively. The cavity is characterized as an optical filter using a BCF with reflectivity that is larger than 95% in a 300 nm range across the E-band and the L-band. Versatile filter characteristics were obtained for different values of the MEMS micromirror slit width and cavity length. A free spectral range (FSR) of about 33 nm and a quality factor of about 196 were obtained for a 5.5 μm width aluminum slit, while an FSR of about 148 nm and a quality factor of about 148 were obtained for a 1.5 μm width gold slit. The presented structure opens the door for wide spectral response transmission-type MEMS filters.

Effects of climate change on bioaccumulation and biomagnification of polycyclic aromatic hydrocarbons in the planktonic food web of a subtropical shallow eutrophic lake in China.

Science.gov (United States)

Tao, Yuqiang; Xue, Bin; Lei, Guoliang; Liu, Fei; Wang, Zhen

2017-04-01

To date effects of climate change on bioaccumulation and biomagnification of chemical pollutants in planktonic food webs have rarely been studied. Recruitments of plankton have shifted earlier due to global warming. Global warming and precipitation patterns are projected to shift seasonally. Whether and how the shifts in plankton phenology induced by climate change will impact bioaccumulation and biomagnification of chemical pollutants, and how they will respond to climate change are largely unknown. Here, we combine data analysis of the past seven decades, high temporal resolution monitoring and model development to test this hypothesis with nine polycyclic aromatic hydrocarbons (PAHs) in the planktonic food web of a subtropical shallow eutrophic lake in China. We find biphasic correlations between both bioconcentration factors and bioaccumulation factors of the PAHs and the mean temperature, which depend on the recruitment temperatures of cyanobacteria, and copepods and cladocerans. The positive correlations between bioconcentration factors, bioaccumulation factors and the mean temperature will be observed less than approximately 13-18 days by 2050-2060 due to the shifts in plankton phenology. The PAHs and their bioaccumulation and biomagnification will respond seasonally and differently to climate change. Bioaccumulation of most of the PAHs will decrease with global warming, with higher decreasing rates appearing in winter and spring. Biomagnification of most of the PAHs from phytoplankton to zooplankton will increase with global warming, with higher increasing rates appearing in winter and spring. Our study provides novel insights into bioaccumulation and biomagnification of chemical pollutants in eutrophic waters under climate change scenarios. Copyright © 2017 Elsevier Ltd. All rights reserved.

Environmental Containment Property Estimation Using QSARs in an Expert System

Science.gov (United States)

1993-01-15

Soil Adsorption , Octanol- Water Partition Coefficients, Water Solubilities, Bioconcentration Factors and the Parachor. J. Agric. Food Chý’m., 1981. 29...CCOO CH3CO CH3SH CH3SH CH2COO CH2SH HCOO HCOO Furfural Furfural CH20 CH30 DOH (CH2OH)2 CH20 I I CH-O Br Br FCH20 C=C CH=C CNH2 CJ’-NH2 C=C Ci,2NH2 DMSO

Influence of nitrogen status on the bioconcentration of hydrophobic organic compounds to Selenastrum capricornutum

DEFF Research Database (Denmark)

Halling-Sørensen, B.; Nyholm, Niels; Kusk, Kresten Ole

2000-01-01

- creased from 17 to 44% of the algal dry weight as a consequence of nitrogen starvation. An increase in total lipid from 17 to 44% should theoretically increase the BCFs by a factor of 2.6. BCFs for PCB 31, PCB 49, PCB 153, and DDT increased with maximum lipid content by factors of 6.3, 8.9, 8.9, and 6...

Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation

Energy Technology Data Exchange (ETDEWEB)

Coat, Sophie, E-mail: coatsophie@gmail.com [EA 926 DYNECAR, Laboratoire de Biologie Marine, UFR Sciences, Universite des Antilles et de la Guyane, BP592, 97159 Pointe-a-Pitre Cedex (France); Monti, Dominique, E-mail: dominique.monti@univ-ag.fr [EA 926 DYNECAR, Laboratoire de Biologie Marine, UFR Sciences, Universite des Antilles et de la Guyane, BP592, 97159 Pointe-a-Pitre Cedex (France); Legendre, Pierre, E-mail: pierre.legendre@umontreal.ca [Departement de Sciences Biologique, Universite de Montreal, C.P. 6128, succursale A, Montreal, Quebec H3C 3J7 (Canada); Bouchon, Claude, E-mail: claude.bouchon@univ-ag.fr [EA 926 DYNECAR, Laboratoire de Biologie Marine, UFR Sciences, Universite des Antilles et de la Guyane, BP592, 97159 Pointe-a-Pitre Cedex (France); Massat, Felix, E-mail: fmassat@ladrome.fr [LDA26, laboratoire Departemental d' Analyses de la Drome, 27 avenue Lautagne, 26000 Valence (France); Lepoint, Gilles, E-mail: g.lepoint@ulg.ac.be [MARE Centre, Laboratoire d' Oceanologie, Universite de Liege, Bat. B6, 4000 Sart Tilman, Belgique (Belgium)

2011-06-15

Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon were measured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examine the bioaccumulation patterns of pollutants through the food web. Chemical analyses showed a general and heavy contamination of the entire food web. They revealed the strong accumulation of pollutants by juveniles of diadromous fishes and shrimps, as they re-enter the river. The role of ecological factors in the bioaccumulation of pesticides was evaluated. Whereas the most persistent pollutants (chlordecone and monohydro-chlordecone) were related to the organisms diet and habitat, bioaccumulation of {beta}-HCH was only influenced by animal lipid content. The biomagnification potential of chlordecone through the food chain has been demonstrated. It highlighted the importance of trophic transfer in this compound bioaccumulation process. In contrast, bioconcentration by passive diffusion from water seemed to be the main exposure route of biota to {beta}-HCH. - Highlights: > We measured OC pesticides and stable isotope ratios in a tropical stream. > Results showed a strong and ubiquitous contamination of the entire food web. > Diadromous juveniles strongly accumulated pollutants when they re-enter the river. > The most persistent pollutant (chlordecone) was related to species diet and habitat. > {beta}-HCH was only influenced by animal lipid content. - This paper determines the bioaccumulation and transfer processes of organochlorine pesticides within the stream food web in Guadeloupe (Caribbean).

Phytoremedial Potential of Typha latifolia, Eichornia crassipes and Monochoria hastata found in Contaminated Water Bodies Across Ranchi City (India).

Science.gov (United States)

Hazra, Moushumi; Avishek, Kirti; Pathak, Gopal

2015-01-01

Phytoremediation is an emerging technology that uses green plants (living machines) for removal of contaminants of concern (COC). These plant species have the potential to remove the COC, thereby restoring the original condition of soil or water environment. The present study focuses on assessing the heavy metals (COC) present in the contaminated water bodies of Ranchi city, Jharkhand, India. Phytoremedial potential of three plant species: Typha latifolia, Eichornia crassipes and Monochoria hastata were assessed in the present study. Heterogenous accumulation of metals was found in the three plant species. It was observed that the ratio of heavy metal concentration was different in different parts, i.e., shoots and roots. Positive results were also obtained for translocation factor of all species with minimum of 0.10 and maximum of 1. It was found experimentally that M. hastata has the maximum BFC for root as 4.32 and shoot as 2.70 (for Manganese). For T. latifolia, BCF of maximum was observed for root (163.5) and respective shoot 86.46 (for Iron), followed by 7.3 and 5.8 for root and shoot (for Manganese) respectively. E. crassipes was found to possess a maximum BCF of 278.6 (for Manganese and 151 (for Iron) and shoot as 142 (for Manganese) and 36.13 (for Iron).

Effects of sewage sludge on Di-(2-ethylhexyl) phthalate uptake by plants

International Nuclear Information System (INIS)

Aranda, J.M.; O'Connor, G.A.; Eiceman, G.A.

1989-01-01

Di-(2-ethylhexyl) phthalate (DEHP) is a priority organic pollutant frequently found in municipal sludges. A greenhouse study was conducted to determine the effect of sludge on plant uptake of 14 C-DEHP (carbonyl labeled). Plants grown included three food chain crops, lettuce (Lactuca sativa L.), carrot (Daucus carota L.) and chile pepper (Capsicum annuum L.) and tall fescue (Festuca arundinacea Schreb.). Net 14 C concentration in plants grown in soil amended with 14 C-DEHP-contaminated sludge was independent of sludge rate (at the same DEHP loading) for lettuce, chile fruit, and carrot roots. Net 14 C concentration, however, was inversely related to sludge rate in carrot tops, fescue, and chile plants. Intact DEHP was not detected in plants by gas chromatography/mass spectrometry analysis. Calculated plant DEHP concentrations (based on measured net 14 C concentrations and DEHP specific activities) were generally correlated better with DEHP soil solution concentrations than with total DEHP soil concentrations. Net 14 C-DEHP bioconcentration factors were calculated from initial soil DEHP concentration and plant fresh weights. Bioconcentration factors ranged from 0.01 to 0.03 for fescue, lettuce, carrots, and chile, suggesting little DEHP uptake. Additionally, because intact DEHP was not detected in any plants, DEHP uptake by plants was of minor importance and would not limit sludge additions to soils used to grow these crops

Coalbed methane and tight gas no longer unconventional resources

International Nuclear Information System (INIS)

Gatens, M.

2006-01-01

Unconventional gas refers to natural gas contained in difficult-to-produce formations that require special drilling and completion techniques to achieve commercial production. It includes tight gas, coal seams, organic shales, and gas hydrates. Canada's vast unconventional gas resource is becoming an increasingly important part of the country's gas supply. The emergence of unconventional gas production in Canada over the past several years has made the unconventional increasingly conventional in terms of industry activity. It was suggested that in order to realize the potential for unconventional gas in Canada, all stakeholders should engage to ensure the development is environmentally responsible. Unconventional gas accounts for nearly one third of U.S. gas production. It also accounts for nearly 5 Bcf per day and growing. The impetus to this sudden growth has been the gradual and increasing contribution of tight sands and limes to Canadian production, which accounts for more than 4 Bcf per day. Coalbed methane (CBM) is at 0.5 Bcf per day and growing. In response to expectations that CBM will reach 2 to 3 Bcf per day over the next 2 decades, Canadian producers are placing more emphasis on unconventional resource plays, including organic shales and gas hydrates. As such, significant growth of unconventional gas is anticipated. This growth will be facilitated by the adoption of U.S..-developed technologies and new Canadian technologies. It was suggested that research and development will be key to unlocking the unconventional gas potential. It was also suggested that the already existing, strong regulatory structure should continue in order to accommodate this growth in a sustainable manner. figs

A comparative study of the effect of clonidine, fentanyl, and the combination of both as adjuvant to intrathecal bupivacaine for postoperative analgesia in total abdominal hysterectomy

Science.gov (United States)

Ahmed, Fareed; Khandelwal, Mamta; Sharma, Anil

2017-01-01

Background and Aims: The aim of this study was to evaluate the level of sensory block, onset and duration of motor block, postoperative analgesia, and adverse effects of combination of clonidine and fentanyl given intrathecally with hyperbaric bupivacaine (HB). Material and Methods: Three hundred and twenty eight patients were randomized into four groups. Group bupivacaine (group B) received 15 mg of HB; group bupivacaine clonidine (group BC) received 15 mg of HB plus 25 μg clonidine; group bupivacaine fentanyl (group BF) received 15 mg of HB plus 25 μg fentanyl and group bupivacaine clonidine fentanyl (group BCF) received 15 mg of HB plus 25 μg clonidine and 25 μg fentanyl intrathecally. All groups were evaluated for level of sensory block, onset and duration of motor block, postoperative analgesia, VAS score, sedation score and adverse effects of study drugs. All the data were analyzed using unpaired t-test. P < 0.05 was considered significant. Results: The level of sensory block, onset, and duration of motor block were comparable in all groups. Total duration of analgesia was 407.3 ± 20 min in group BCF compared to 242.1 ± 2 min and 209.2 ± 16 in groups BC and BF, respectively. Lesser doses of rescue analgesic were required in group BCF. The time interval from intrathecal injection to two-segment regression was statistically significant in study groups. Only 2.4% patients showed mild sedation in BCF group. Conclusion: We found that combination of intrathecal clonidine and fentanyl along with bupivacaine increases the total duration of analgesia without significant side effects. PMID:28413281

Plastic scintillation dosimetry: Optimal selection of scintillating fibers and scintillators

International Nuclear Information System (INIS)

Archambault, Louis; Arsenault, Jean; Gingras, Luc; Sam Beddar, A.; Roy, Rene; Beaulieu, Luc

2005-01-01

Scintillation dosimetry is a promising avenue for evaluating dose patterns delivered by intensity-modulated radiation therapy plans or for the small fields involved in stereotactic radiosurgery. However, the increase in signal has been the goal for many authors. In this paper, a comparison is made between plastic scintillating fibers and plastic scintillator. The collection of scintillation light was measured experimentally for four commercial models of scintillating fibers (BCF-12, BCF-60, SCSF-78, SCSF-3HF) and two models of plastic scintillators (BC-400, BC-408). The emission spectra of all six scintillators were obtained by using an optical spectrum analyzer and they were compared with theoretical behavior. For scintillation in the blue region, the signal intensity of a singly clad scintillating fiber (BCF-12) was 120% of that of the plastic scintillator (BC-400). For the multiclad fiber (SCSF-78), the signal reached 144% of that of the plastic scintillator. The intensity of the green scintillating fibers was lower than that of the plastic scintillator: 47% for the singly clad fiber (BCF-60) and 77% for the multiclad fiber (SCSF-3HF). The collected light was studied as a function of the scintillator length and radius for a cylindrical probe. We found that symmetric detectors with nearly the same spatial resolution in each direction (2 mm in diameter by 3 mm in length) could be made with a signal equivalent to those of the more commonly used asymmetric scintillators. With augmentation of the signal-to-noise ratio in consideration, this paper presents a series of comparisons that should provide insight into selection of a scintillator type and volume for development of a medical dosimeter

Readability of Orthopaedic Oncology-related Patient Education Materials Available on the Internet.

Science.gov (United States)

Shah, Akash K; Yi, Paul H; Stein, Andrew

2015-12-01

A person's health literacy is one of the most important indicators of a patient's health status. According to national recommendations, patient education materials should be written at no higher than the sixth- to eighth-grade reading level. The purpose of our study was to assess the readability of online patient education materials related to orthopaedic oncology on the websites of the American Academy of Orthopaedic Surgeons (AAOS), American Cancer Society (ACS), Bone and Cancer Foundation (BCF), and National Cancer Institute (NCI). We searched the online patient education libraries of the AAOS, ACS, BCF, and NCI for all articles related to orthopaedic oncology. The Flesch-Kincaid (FK) readability score was calculated for each article and compared between sources. A total of 227 articles were identified with an overall mean FK grade level of 9.8. Stratified by source, the mean FK grade levels were 10.1, 9.6, 11.1, and 9.5 for the AAOS, ACS, BCF, and NCI, respectively (P education materials related to orthopaedic oncology appear to be written at a level above the comprehension ability of the average patient. Copyright 2015 by the American Academy of Orthopaedic Surgeons.

Natural gas imports and exports. Second quarter report 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-31

This quarter`s feature report focuses on natural gas exports to Mexico. OFP invites ideas from the public on future topics dealing with North American natural gas import/export trade. Such suggestions should be left on OFP`s electronic bulletin board. Natural Gas exports to Mexico continued to grow and reached an historic high for the month of June (7.8 Bcf). Two new long-term contracts were activated; Pennsylvania Gas & Water Company began importing 14.7 MMcf per day from TransCanada PipeLines Ltd., and Renaissance Energy (U.S.) Inc. began importing 2.8 MMcf per day from Renaissance Energy Ltd. for resale to Delmarva Power & Light Company. Algerian LNG imports remained stagnant with only one tanker being imported by Pan National Gas Sales, Inc. (Pan National). During the first six months of 1995, data indicates gas imports increased by about 10 percent over the 1994 level (1,418 vs. 1,285 Bcf), with Canadian imports increasing by 14 percent and Algerian imports decreasing by 81 percent. During the same time period, exports increased by 18 percent (83 vs. 70.1 Bcf).

East, West German gas pipeline grids linked

International Nuclear Information System (INIS)

Anon.

1992-01-01

This paper reports that Ruhrgas AG, Essen, has started up the first large diameter gas pipeline linking the gas grids of former East and West Germany. Ruhrgas last month placed in service a 40 in., 70 km line at Vitzeroda, near Eisenach, linking a new Ruhrgas pipeline in Hesse state with a 330 km gas pipeline built last year in Thuringia and Saxony states by Erdgasversorgungs GmbH (EVG), Leipzig. The new link enables pipeline operator EVG to receive 70 bcf/year of western European gas via Ruhrgas, complementing the 35 bcf/year of gas coming from the Commonwealth of Independent States via Verbundnetz Gas AG (VNG), Leipzig

Biotransformation and detoxication of molinate (Ordram) in fish

International Nuclear Information System (INIS)

Tjeerdema, R.S.

1987-01-01

Bioconcentration, deputation, and biotransformation of molinate were compared in common carp (cyprinus carpio), striped bass (Morone saxatilis), and white sturgeon (acipenser transmontanus) using a flow-through metabolism system. When compared to static conditions, flowing water improved oxygenation, decreased chemical volatilization and remetabolism, and run through a macroreticular resin, improved waste-product collection. Metabolite analysis employed gradient high-pressure liquid chromatography. Exposure to 100 μg L -1 [ring- 14 C]molinate for 24 h resulted in bioconcentration factors of 30.5 (carp), 25.3 (bass), and 19.7 (sturgeon); differences were not significant (all, P > 0.05). 14 C depuration by common carp was significantly slower than that by either striped bass or white sturgeon (both, P < 0.01). All three species oxidized molinate to a number of products and hydrolyzed, or conjugated with glutathione (GSH), the sulfoxide or sulfone, ultimately producing the mercapturic acid; carp and sturgeon also formed a D-glucuronic acid conjugate. Common carp were significantly less capable of sulfoxidation and GSH conjugation than either striped bass (P < 0.05) or white sturgeon (P < 0.01). Therefore, the selective toxicity of molinate in carp may be due to less efficient depuration and metabolic deactivation

Metal-resistant rhizobacteria isolates improve Mucuna deeringiana phytoextraction capacity in multi-metal contaminated soils from a gold mining area.

Science.gov (United States)

Boechat, Cácio Luiz; Giovanella, Patricia; Amorim, Magno Batista; de Sá, Enilson Luiz Saccol; de Oliveira Camargo, Flávio Anastácio

2017-01-01

Phytoremediation consists of biological techniques for heavy metal remediation, which include exploring the genetic package of vegetable species to remove heavy metals from the environment. The goals of this study were to investigate heavy metal and bioaugmentation effects on growth and nutrient uptake by Mucuna deeringiana; to determine the metal translocation factor and bioconcentration factor and provide insight for using native bacteria to enhance heavy metal accumulation. The experiment was conducted under greenhouse conditions using a 2 × 4 factorial scheme with highly and slightly contaminated soil samples and inoculating M. deeringiana with three highly lead (Pb +2 )-resistant bacteria Kluyvera intermedia (Ki), Klebsiella oxytoca (Ko), and Citrobacter murliniae (Cm) isolated from the rhizosphere of native plants identified as Senecio brasiliensis (Spreng.) Less., Senecio leptolobus DC., and Baccharis trimera (Less) DC., respectively. The increased heavy metal concentrations in soil samples do not decrease the root dry mass of M. deeringiana, concerning the number and dry weight of nodules. The shoot dry mass is reduced by the increasing concentration of heavy metals in soil associated with Kluyvera intermedia and Klebsiella oxytoca bacteria. The number of nodules is affected by heavy metals associated with Citrobacter murliniae bacteria. The bacteria K. intermedia, C. murliniae, and K. oxytoca increase the lead and cadmium available in the soil and enhanced metal uptake by Mucuna deeringiana. The M. deeringiana specie has characteristics that make it hyperaccumulate copper and zinc. The translocation and bioconcentration factors for M. deeringiana characterize it as a promising candidate to phytostabilize multi-metal contaminated soils.

Cs phytoremediation by Sorghum bicolor cultivated in soil and in hydroponic system.

Science.gov (United States)

Wang, Xu; Chen, Can; Wang, Jianlong

2017-04-03

Cs accumulation characteristics by Sorghum bicolor were investigated in hydroponic system (Cs level at 50-1000 μmol/L) and in soil (Cs-spiked concentration was 100 and 400 mg/kg soil). Two varieties of S. bicolor Cowly and Nengsi 2# grown on pot soil during the entire growth period (100 days) did not show significant differences on the height, dry weight (DW), and Cs accumulation. S. bicolor showed the potential phytoextraction ability for Cs-contaminated soil with the bioaccumulation factor (BCF) and the translocation factor (TF) values usually higher than 1 in soil system and in hydroponic system. The aerial parts of S. bicolor contributed to 86-92% of the total removed amounts of Cs from soil. Cs level in solution at 100 μmol/L gave the highest BCF and TF values of S. bicolor. Cs at low level tended to transfer to the aerial parts, whereas Cs at high level decreased the transfer ratio from root to shoot. In soil, the plant grew well when Cs spiked level was 100 mg/kg soil, but was inhibited by Cs at 400 mg/kg soil with Cs content in sorghum reaching 1147 mg/kg (roots), 2473 mg/kg (stems), and 2939 mg/kg (leaves). In hydroponic system, average Cs level in sorghum reached 5270 mg/kg (roots) and 4513 mg/kg (aerial parts), without significant damages to its biomass at 30 days after starting Cs treatment. Cs accumulation in sorghum tissues was positively correlated with the metal concentration in medium.

Calibrating passive sampling and passive dosing techniques to lipid based concentrations

DEFF Research Database (Denmark)

Mayer, Philipp; Schmidt, Stine Nørgaard; Annika, A.

2011-01-01

Equilibrium sampling into various formats of the silicone polydimethylsiloxane (PDMS) is increasingly used to measure the exposure of hydrophobic organic chemicals in environmental matrices, and passive dosing from silicone is increasingly used to control and maintain their exposure in laboratory...... coated vials and with Head Space Solid Phase Microextraction (HS-SPME) yielded lipid based concentrations that were in good agreement with each other, but about a factor of two higher than measured lipid-normalized concentrations in the organisms. Passive dosing was applied to bioconcentration...

Human toxicity as a criterion in the environmental assessment of products

DEFF Research Database (Denmark)

Hauschild, Michael Zwicky; Olsen, Stig Irving; Wenzel, Henrik

1998-01-01

. The assessment proceeds through the steps of classification, characterization, normalization and valuation. In the classification step attention is focused on intrinsic toxicity, low biodegradability and potential for bioconcentration as properties that predicpose a substance for ecotoxicity. No concrete values...... references derived for each of these scenarios are presented as personal equivalents for citizens in the considered region. Valuation Applying the "distance to target principle to the present Danish political reduction targets for toxicity a weighting factor is derived to be used in the quantitative weighing...

Copper regulation and homeostasis of Daphnia magna and Pseudokirchneriella subcapitata: influence of acclimation

International Nuclear Information System (INIS)

Bossuyt, Bart T.A.; Janssen, Colin R.

2005-01-01

This study aimed to evaluate (1) the capacity of the green alga Pseudokirchneriella subcapitata and the waterflea Daphnia magna to regulate copper when exposed to environmentally realistic copper concentrations and (2) the influence of multi-generation acclimation to these copper concentrations on copper bioaccumulation and homeostasis. Based on bioconcentration factors, active copper regulation was observed in algae up to 5 μg Cu L -1 and in daphnids up to 35 μg Cu L -1 . Constant body copper concentrations (13 ± 4 μg Cu g DW -1 ) were observed in algae exposed to 1 through 5 μg Cu L -1 and in daphnids exposed to 1 through 12 μg Cu L -1 . At higher exposure concentrations, there was an increase in internal body copper concentration, while no increase was observed in bioconcentration factors, suggesting the presence of a storage mechanism. At copper concentrations of 100 μg Cu L -1 (P. subcapitata) and 150 μg Cu L -1 (D. magna), the significant increases observed in body copper concentrations and in bioconcentration factors may be related to a failure of this regulation mechanism. For both organisms, internal body copper concentrations lower than 13 μg Cu g DW -1 may result in copper deficiency. For P. subcapitata acclimated to 0.5 and 100 μg Cu L -1 , body copper concentrations ranged (mean ± standard deviation) between 5 ± 2 μg Cu g DW -1 and 1300 ± 197 μg Cu g DW -1 , respectively. For D. magna, this value ranged between 9 ± 2 μg Cu g DW -1 and 175 ± 17 μg Cu g DW -1 for daphnids acclimated to 0.5 and 150 μg Cu L -1 . Multi-generation acclimation to copper concentrations ≥12 μg Cu L -1 resulted in a decrease (up to 40%) in body copper concentrations for both organisms compared to the body copper concentration of the first generation. It can be concluded that there is an indication that P. subcapitata and D. magna can regulate their whole body copper concentration to maintain copper homeostasis within their optimal copper range and

Concentration dependence of biotransformation in fish liver S9: Optimizing substrate concentrations to estimate hepatic clearance for bioaccumulation assessment.

Science.gov (United States)

Lo, Justin C; Allard, Gayatri N; Otton, S Victoria; Campbell, David A; Gobas, Frank A P C

2015-12-01

In vitro bioassays to estimate biotransformation rate constants of contaminants in fish are currently being investigated to improve bioaccumulation assessments of hydrophobic contaminants. The present study investigates the relationship between chemical substrate concentration and in vitro biotransformation rate of 4 environmental contaminants (9-methylanthracene, pyrene, chrysene, and benzo[a]pyrene) in rainbow trout (Oncorhynchus mykiss) liver S9 fractions and methods to determine maximum first-order biotransformation rate constants. Substrate depletion experiments using a series of initial substrate concentrations showed that in vitro biotransformation rates exhibit strong concentration dependence, consistent with a Michaelis-Menten kinetic model. The results indicate that depletion rate constants measured at initial substrate concentrations of 1 μM (a current convention) could underestimate the in vitro biotransformation potential and may cause bioconcentration factors to be overestimated if in vitro biotransformation rates are used to assess bioconcentration factors in fish. Depletion rate constants measured using thin-film sorbent dosing experiments were not statistically different from the maximum depletion rate constants derived using a series of solvent delivery-based depletion experiments for 3 of the 4 test chemicals. Multiple solvent delivery-based depletion experiments at a range of initial concentrations are recommended for determining the concentration dependence of in vitro biotransformation rates in fish liver fractions, whereas a single sorbent phase dosing experiment may be able to provide reasonable approximations of maximum depletion rates of very hydrophobic substances. © 2015 SETAC.

A novel embryo culture media supplement that improves pregnancy rates in mice.

Science.gov (United States)

Highet, A R; Bianco-Miotto, T; Pringle, K G; Peura, A; Bent, S; Zhang, J; Nottle, M B; Thompson, J G; Roberts, C T

2017-03-01

The preimplantation embryo in vivo is exposed to numerous growth factors in the female reproductive tract, which are not recapitulated in embryo culture media in vitro The IGF2 and plasminogen activator systems facilitate blastocyst development. We hypothesized that the addition of IGF2 in combination with urokinase plasminogen activator (uPA) and plasminogen could improve rates of blastocyst hatching and implantation in mice. B6BcF1 and CBAB6F2 mouse embryos were divided into one of four supplemented culture media treatment groups: (1) control (media only); (2) 12.5 nM IGF2; (3) 10 µg/mL uPA and 5 µg/mL plasminogen; or (4) a combination of IGF2, uPA and plasminogen treatments. Embryo development to blastocyst stage and hatching were assessed before transfer to pseudopregnant recipient females and implantation, pregnancy rates and postnatal growth were assessed. After 90.5 h of culture, IGF2 + U + P treatment increased the percentage of B6BcF1 embryos that were hatching/hatched and percentage developing to blastocyst stage compared with controls (P culture, IGF2, uPA and plasminogen supplementation of culture media can improve pregnancy success, but the effect of treatment is dependent on the mouse strain. © 2017 Society for Reproduction and Fertility.

A Software Framework for Blast Event Simulation

National Research Council Canada - National Science Library

Swensen, D. A; Denison, M. K; Guilkey, James; Harman, Todd; Goetz, Richard

2006-01-01

.... The BCF will provide a virtual test-bed where disparate computational models can seamlessly interact with one another to provide a unified modeling solution for blast-vehicle-occupant scenarios...

A Numerical Study of Nonlinear Nonhydrostatic Conditional Symmetric Instability in a Convectively Unstable Atmosphere.

Science.gov (United States)

Seman, Charles J.

1994-06-01

Nonlinear nonhydrostatic conditional symmetric instability (CSI) is studied as an initial value problem using a two-dimensional (y, z)nonlinear, nonhydrostatic numerical mesoscale/cloud model. The initial atmosphere for the rotating, baroclinic (BCF) simulation contains large convective available potential energy (CAPE). Analytical theory, various model output diagnostics, and a companion nonrotating barotropic (BTNF) simulation are used to interpret the results from the BCF simulation. A single warm moist thermal initiates convection for the two 8-h simulations.The BCF simulation exhibited a very intricate life cycle. Following the initial convection, a series of discrete convective cells developed within a growing mesoscale circulation. Between hours 4 and 8, the circulation grew upscale into a structure resembling that of a squall-line mesoscale convective system (MCS). The mesoscale updrafts were nearly vertical and the circulation was strongest on the baroclinically cool side of the initial convection, as predicted by a two-dimensional Lagrangian parcel model of CSI with CAPE. The cool-side mesoscale circulation grew nearly exponentially over the last 5 h as it slowly propagated toward the warm air. Significant vertical transport of zonal momentum occurred in the (multicellular) convection that developed, resulting in local subgeostrophic zonal wind anomalies aloft. Over time, geostrophic adjustment acted to balance these anomalies. The system became warm core, with mesohigh pressure aloft and mesolow pressure at the surface. A positive zonal wind anomaly also formed downstream from the mesohigh.Analysis of the BCF simulation showed that convective momentum transport played a key role in the evolution of the simulated MCS, in that it fostered the development of the nonlinear CSI on mesoscale time scales. The vertical momentum transport in the initial deep convection generated a subgeostrophic zonal momentum anomaly aloft; the resulting imbalance in pressure

Exposure and food web transfer of pharmaceuticals in ospreys (Pandion haliaetus): Predictive model and empirical data

Science.gov (United States)

Lazarus, Rebecca S.; Rattner, Barnett A.; Du, Bowen; McGowan, Peter C.; Blazer, Vicki S.; Ottinger, Mary Ann

2015-01-01

The osprey (Pandion haliaetus) is a well-known sentinel of environmental contamination, yet no studies have traced pharmaceuticals through the water–fish–osprey food web. A screening-level exposure assessment was used to evaluate the bioaccumulation potential of 113 pharmaceuticals and metabolites, and an artificial sweetener in this food web. Hypothetical concentrations in water reflecting “wastewater effluent dominated” or “dilution dominated” scenarios were combined with pH-specific bioconcentration factors (BCFs) to predict uptake in fish. Residues in fish and osprey food intake rate were used to calculate the daily intake (DI) of compounds by an adult female osprey. Fourteen pharmaceuticals and a drug metabolite with a BCF greater than 100 and a DI greater than 20 µg/kg were identified as being most likely to exceed the adult human therapeutic dose (HTD). These 15 compounds were also evaluated in a 40 day cumulative dose exposure scenario using first-order kinetics to account for uptake and elimination. Assuming comparable absorption to humans, the half-lives (t1/2) for an adult osprey to reach the HTD within 40 days were calculated. For 3 of these pharmaceuticals, the estimated t1/2 in ospreys was less than that for humans, and thus an osprey might theoretically reach or exceed the HTD in 3 to 7 days. To complement the exposure model, 24 compounds were quantified in water, fish plasma, and osprey nestling plasma from 7 potentially impaired locations in Chesapeake Bay. Of the 18 analytes detected in water, 8 were found in fish plasma, but only 1 in osprey plasma (the antihypertensive diltiazem). Compared to diltiazem detection rate and concentrations in water (10/12 detects,

Medium-chain chlorinated paraffins (MCCPs): a review of bioaccumulation potential in the aquatic environment.

Science.gov (United States)

Thompson, Roy; Vaughan, Martin

2014-01-01

Chlorinated paraffins (CPs) are high molecular weight organochlorine compounds that have been used in a variety of industrial applications for many years. Medium-chain chlorinated paraffins (MCCPs) (CAS 85535-85-9; Alkanes, C14-17 , chloro) are currently under investigation as potential persistent bioaccumulative toxic (PBT) compounds. In this article, the bioaccumulation potential of MCCPs is assessed using a tiered framework proposed after a recent Society of Environmental Toxicology and Chemistry (SETAC) Pellston Workshop in 2008. The framework proposes the use of physicochemical properties and modeling assessment, bioconcentration/bioaccumulation (BCF/BAF) assessment, biomagnification (BMF) assessment, and trophic magnification factor (TMF) assessment. It is hoped that use of this framework could harmonize and improve the efficiency and effectiveness of the chemical substance evaluation screening process for PBT properties. When applied to MCCPs, the following conclusions were made: empirical physiochemical data is available negating the use of models; laboratory BCFs range from 1000 to 15 000 (growth-corrected lipid normalized values) for 2 MCCP structures; field BAFs were an order of magnitude higher than the trigger criterion for "B status possible"; although results may not meet acceptance criteria for field studies, laboratory-derived BMFs for a number of C14-17 chlorinated alkanes were less than the trigger value of 1 (based on whole-body concentrations) whereas field-derived BMFs were less than 1 (based on lipid corrected values [generally used for field data] excluding one measure for sculpin, [Cottus cognatus]-Diporeia that was based on only one detectable sample); and finally, TMFs were less than the trigger criterion value of 1, which are considered the most convincing evidence for bioaccumulative properties of a compound and the "Gold Standard" measure of bioaccumulation. This article also discusses the uncertainties surrounding the published data

Contamination status and accumulation features of persistent organochlorines in pet dogs and cats from Japan

International Nuclear Information System (INIS)

Kunisue, Tatsuya; Nakanishi, Shigeyuki; Watanabe, Mafumi; Abe, Takao; Nakatsu, Susumu; Kawauchi, Sakio; Sano, Akihiko; Horii, Akira; Kano, Yasumasa; Tanabe, Shinsuke

2005-01-01

Concentrations of persistent organochlorines (OCs) such as polychlorinated dibenzo-p-dioxin (PCDDs), dibenzofurans (PCDFs), biphenyls, dichlorodiphenyltrichloroethane and their metabolites (DDTs), hexachlorocyclohexane isomers, hexachlorobenzene, and chlordane compounds were determined in genital organs of pet dogs and cats and pet foods from Japan. Levels of OCs in dogs were relatively lower than those in cats, while residue levels in their diets were almost similar, implying that accumulation and elimination mechanisms of these contaminants are different between dogs and cats. When bioconcentration factors (BCFs) were estimated from concentrations of OCs in dogs, cats, and their diets, BCFs of all the OCs except PCDD/DFs exceeded 1.0 in cats. On the other hand, in all the dogs, BCFs of DDTs were below 1.0, suggesting that dogs do not bioconcentrate DDTs. Furthermore, BCFs of all the OCs except PCDD/DFs in dogs were notably lower than those in cats, suggesting that dogs have higher metabolic and elimination capacity for these contaminants than cats. When residue levels of OCs in livers, adipose tissue, and genital organs of two pet dogs were examined, hepatic sequestration of PCDD/DFs and oxychlordane was observed. - Pet dogs may have higher metabolic and elimination capacity for organochlorines than pet cats

SSPM based radiation sensing: Preliminary laboratory and clinical results

International Nuclear Information System (INIS)

Konnoff, Daniel C.; Plant, Thomas K.; Shiner, Elizabeth

2011-01-01

Recent Solid State Photomultiplier (SSPM) technology has matured, reaching a performance level that is suitable for replacement of the ubiquitous photomultiplier tube in selected applications for environmental radiation monitoring, clinical dosimetry, and medical imaging purposes. The objective of this work is low signal level laboratory and high signal level clinical testing of the Hamamatsu MPPC (S10362-11-050C), Photonique SSPM (0810G1), and Voxtel SiPM (SQBF-EKAA/SQBF-EIOA) SSPMs coupled to different inorganic scintillator crystals (Prelude 420, BGO), inorganic doped glass scintillator material SiO 2 :Cu 2+ and organic BCF-12 plastic scintillating fibers, used as detector elements. Plastic Optical Fibers (POFs) and Glass Optical Fibers (GOFs) are used as signal conduits for laboratory and clinical testing. Further, reduction of electron-beam-generated Cerenkov light in optical fibers is facilitated by the inclusion of metalized air-core capillary tubing between the BCF-12 plastic scintillating fiber and the POF. In a clinical setting dose linearity, percent depth dose, and angular measurements for 6 MV/18 MV photon beams and 9 MeV electron beams are compared with and without the use of the air-core capillary tubing for BCF-12 plastic scintillating fiber. These same measurements are repeated for SiO 2 :Cu 2+ scintillator material without air-core capillary tubing.

WE-DE-201-10: Pitfalls When Using Ruby as An Inorganic Scintillator Detector for Ir-192 Brachytherapy Dosimetry

Energy Technology Data Exchange (ETDEWEB)

Kertzscher, G; Beddar, S [The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

2016-06-15

Purpose: To study the promising potential of inorganic scintillator detectors (ISDs) and investigate various unwanted luminescence properties which may compromise their accuracy. Methods: The ISDs were comprised of a ruby crystal coupled to a polymethyl methacrylate (PMMA) fiber-optic cable and a charged coupled device camera. A new type of ISD was manufactured and included a long-pass filter that was sandwiched between the crystal and the fiber-optic cable. The purpose of the filter was to suppress the Cerenkov and fluorescence background light induced in the PMMA (the stem signal) from striking the ruby crystal, generating unwanted ruby excitation. A variety of experiments were performed to characterize the ruby based ISDs. The relative contribution of the induced ruby signal and the stem signal were quantified while exposing the detector and a bare fiber-optic cable to a high dose rate (HDR) brachytherapy (BT) source, respectively. The unwanted ruby excitation was quantified while irradiating the fiber-optic cable with the detector volume shielded. Other experiments addressed time-dependent luminescence properties and a comparison to other commonly used organic scintillator detectors (BCF-12, BCF-60). Results: When the BT source dwelled 0.5 cm away from the fiber-optic cable, the unwanted ruby excitation amounted to >5% of the total signal if the source-distance from the scintillator was >7 cm. However, the unwanted excitation was suppressed to <1% if the ISD incorporated an optic filter. The stem signal was suppressed with a 20 nm band-pass filter and was <3% as long as the source-distance was <7 cm. The ruby based ISDs generated signal up to 20(40) times that of BCF-12(BCF-60). Conclusion: The study presents solutions to unwanted luminescence properties of ruby based ISDs for HDR BT. An optic filter should be sandwiched between the scintillator volume and the fiber-optic cable to prevent the stem signal to excite the ruby crystal.

The Environmentally Sound Aquaculture Strategies Based on Bioaccumulation of Heavy Metal of Lead (Pb) on Seaweed of Gracilaria verrucosa on Aquaculture Areas of MuararejaVillage, Tegal City

Science.gov (United States)

Nurjanah; Ambariyanto; Supriharyono; Yulianto, Bambang

2018-02-01

Community activities such as industry, trade, animal husbandry and agriculture and ssettlements resulting in heavy metals of lead (Pb) can be accumulated in water, sediment and seaweed Gracillaria verrucosa. It can contaminate ponds and affect aquaculture activities in Tegal. Seaweed Gracilaria verrucosa is afisheries commodity that has economical value and cultivated in the area of aquaculture MuararejaTegal. It can serve as fitoremedian that will help reduce the impact of heavy metal pollution due to its ability to accumulate pollutants. The objective of this study was to analyze bioaccumulation of heavy metals of lead (Pb) and its relationship with water quality management in order to develop seaweed cultivation of Gracillaria verrucosa in ponds in the area of aquaculture MuararejaTegal. The method used in this study is a survey, analysis of heavy metals of lead (Pb) in pond water, sediment and seaweed using Atomic Absorption Spectrophotometer (AAS) and the data were analyzed by descriptive quantitative. Bioconcentration of lead (Pb) during the dry season in pond water, sediment and seaweed Gracillaria verrucosa was measured from 0.003 to 0.025 ppm,5.543 to 23.699 ppm and 0.209 to 0.326 ppm respectively. While in the rainy season bioconcentration of lead (Pb) are from 0.003 to 0.015 ppm, sediment from 6.377 to 9.858 ppm and 0.209 to 0.326 ppm respectively. Bioconcentration of Pb in dry season was higher than in the rainy season and the biggest bioconcentration was found in the sediment pond waters. Pb bioaccumulation low and still below the quality standards of the Ministry of Environment decision 51 of 2004 so that the product is safe for consumption.

Influence of ortho-substitution homolog group on polychlorobiphenyl bioaccumulation factors and fugacity ratios in plankton and zebra mussels (Dreissena polymorpha)

Energy Technology Data Exchange (ETDEWEB)

Willman, E.J.; Manchester-Neesvig, J.B.; Agrell, C.; Armstrong, D.E.

1999-07-01

The accumulation of a set of non- and mono-ortho (coplanar) PCB congeners in aquatic ecosystems is of interest due to their dioxin-like toxicities. Chemical properties (octanol-water partition coefficients) suggest that the coplanar congeners may accumulate in organisms to a greater extent than homologs with greater ortho substitution. The authors analyzed a set of 65 PCB congeners with zero to four ortho-chlorines from seven homolog groups in water, suspended particulate matter, and zebra mussels from Green Bay, Wisconsin, USA, on four dates throughout the ice-free season. The suspended particulate matter was separated by size and characterized as phytoplankton or zooplankton using diagnostic carotenoid pigments and light microscopy. Median bioconcentration factors (BCFs) for accumulation from water by phytoplankton and bioaccumulation factors (BAFs) for accumulation from water plus food by zooplankton and zebra mussels ranged from 1 x 10{sup 4} to 1 x 10{sup 6} and were generally the greatest for the tetra- to heptachlorobiphenyls. The average coplanar congener BCFs and BAFs for accumulation from water by phytoplankton, zooplankton, and zebra mussels for the tri-, tetra-, and pentachlorobiphenyls were 54% larger than corresponding values for their homologs. Biomagnification factors (BMFs) of the tetra-, penta-, and hexachlorobiphenyls between zooplankton and zebra mussels and their food source, phytoplankton, typically ranged between 1 and 10, but the average coplanar congener BMFs were 25% less than values for their corresponding homologs. The tendency for coplanar congeners to accumulate to a lesser extent between trophic levels was not as large as their tendency to accumulate from water to a greater extent. Based on accumulation factors, the authors conclude that the dioxin-like tetra- and pentachlorobiphenyls generally accumulate in the phytoplankton, zooplankton, and zebra mussels of the Green Bay ecosystem to a greater extent than other congeners. Fugacity

A new Triassic shortening-extrusion tectonic model for Central-EasternAsia: Structural, geochronological and paleomagnetic investigations in the Xilamulun Fault (North China)

Science.gov (United States)

Zhao, Pan; Faure, Michel; Chen, Yan; Xu, Bei

2017-04-01

At the northern margin of the North China Block (NCB), the Xilamulun Fault (XMF) is a key belt to decipher the tectonic evolution of Central-Eastern Asia, as it records the Paleozoic final closure of the Paleo-Asian Ocean, and localizes a Late Triassic intracontinental deformation. In this study, structural analysis, 40Ar-39Ar dating, and paleomagnetic studies were performed to investigate the kinematics of the XMF and to further discuss its Triassic geodynamic significance in the Central-Eastern Asia framework after the Paleozoic Central Asian Orogenic evolution. The structural analyses reveal two phases of ductile deformation. The first one (D1), which displays N-verging and E-W trending folds, is related to the Early Paleozoic collisional event between the NCB and the Songliao-Hunshandake Block (SHB). The second phase (D2) displays a high-angle foliation and a pervasive sub-horizontalE-W stretching lineation with kinematic criteria indicative of dextral strike-slip shearing. The 40Ar-39Ar dating on mylonitic granite places the main shearing event around 227-209 Ma. This D2 shearing is coeval with that of the dextral strike-slip Bayan Obo-Chifeng Fault (BCF) and the Chicheng-Fengning-Longhua Fault to the south, which together constitute a dextral shearing fault system on the northern margin of the NCB during the Late Triassic. The paleomagnetic study performed on the Middle Permian Guangxingyuan pluton, located between the XMF and BCF, documents a local clockwise rotation of this pluton with respect to the NCB and SHB. Our multidisciplinary study suggests anNNW-SSE shortening and strike-slip shearing dominated tectonic setting on the northern margin of the NCB during the Late Triassic. Combining the contemporaneous dextral strike-slip movements of the XMF and BCF in northern China and the sinistral strike-slip movement of East Gobi Fault (EGF) in southeastern Mongolia with the large-scale tectonic framework, a Late Triassic NNW-SSE shortening-eastward extrusion

Qatar chooses Snam to market LNG in Europe

International Nuclear Information System (INIS)

Anon.

1992-01-01

This paper reports that Qatar has chosen Italy's Snam SpA as its European partner to sell liquefied natural gas to Europe from a $4.8 billion joint venture project involving supergiant North offshore gas field. State owned Qatar General petroleum Corp. (QGPC) and Snam signed an agreement in Doha to create a joint company owned 65% by QGPC and the remainder by Snam. Italy's state electricity monopoly, ENEL, which is seeking Qatari gas a fuel for its power plants, may later acquire part of Snam's interest in the project. The joint venture will transport and market North LNG to Europe. Exports to Europe by Snam via Italy, to begin in 1997, are expected to be 283 bcf/year at first and may climb to 459 bcf/year, depending upon demand

nigeria

African Journals Online (AJOL)

Rose

nigrodigitatus and other environmental segments were collected from five sites along Taylor Creek, southern Nigeria, and some ... The ecological distribution of the log (BCF) values was, for all the heavy metals, ..... Fresenius J. Anal. Chem.

Phytoremediation of Pb and Hg by using Scirpus mucronatus with addition of bacterial inoculums

International Nuclear Information System (INIS)

Hamzah, A.; Yatim, N.I.; Sarmani, S.B.

2015-01-01

Two heavy metal-resistant rhizobacteria bacteria (Brevundimonas diminuta SF-S1-5 and Alcaligenes faecalis SF-S1-60) were bioaugmented in sand and also spiked with 100 ppm Pb and 1 ppm Hg and the removal of these metals was monitored using plant, Scirpus mucronatus. The highest accumulation of Pb and Hg were obtained in the root of S. mucronatus inoculated with A. faecalis at day 42 and 28, respectively. Plant inoculated with A. faecalis also showed the highest bioaccumulation coefficient and bioconcentration factor values > 1 compared to plant inoculated with B. diminuta and control. (author)

Biochemical impacts of Hg in Mytilus galloprovincialis under present and predicted warming scenarios.

Science.gov (United States)

Coppola, Francesca; Almeida, Ângela; Henriques, Bruno; Soares, Amadeu M V M; Figueira, Etelvina; Pereira, Eduarda; Freitas, Rosa

2017-12-01

The interest in the consequences of climate change on the physiological and biochemical functioning of marine organisms is increasing, but the indirect and interactive effects resulting from warming on bioconcentration and responsiveness to pollutants are still poorly explored, particularly in terms of cellular responses. The present study investigated the impacts of Hg in Mytilus galloprovincialis under control (17°C) and warming (21°C) conditions, assessing mussels Hg bioconcentration capacity, metabolic and oxidative status after 14 and 28days of exposure. Results obtained showed greater impacts in mussels exposed for 28days in comparison to 14days of exposure. Furthermore, our findings revealed that the increase in temperature from 17 to 21°C reduced the bioconcentration of Hg by M. galloprovincialis, which may explain higher mortality rates at 17°C in comparison to 21°C. Lower Hg concentration at 21°C in mussels tissue may result from valves closure for longer periods, identified by reduced energy reserves consumption at higher temperature, which in turn might also contributed to higher oxidative stress in organisms exposed to this condition. The highest LPO levels observed in mussels exposed to higher temperatures alone indicate that warming conditions will greatly affect M. galloprovincialis. Furthermore, the present study showed that the impacts induced by the combination of Hg and warming were similar to the ones caused by increased temperature acting alone, mainly due to increased antioxidant defenses in organisms under combined effects of Hg and warming, suggesting that warming was the factor that mostly contributed to oxidative stress in mussels. Although higher mortality was observed in individuals exposed to 17°C and Hg compared to organisms exposed to Hg at 21°C, the oxidative stress induced at higher temperature may generate negative consequences on mussels reproductive and feeding capacity, growth and, consequently, on population

The influence of humic substance on Cd accumulation of phytostabilizer Athyrium wardii (Hook.) grown in Cd-contaminated soils.

Science.gov (United States)

Zhan, Juan; Li, Tingxuan; Yu, Haiying; Zhang, Xizhou; Zhao, Li

2016-09-01

The application of organic amendments into heavy metal contaminated soil is considered as an environmentally friendly technique to promote the potential of phytoremediation. A pot experiment was carried out to evaluate the effect of humic substances on growth, cadmium (Cd) accumulation and phytostabilization potential of the mining ecotype (ME) and the corresponding non-mining ecotype (NME) of Athyrium wardii (Hook.) grown in Cd-contaminated soils. The addition of the humic substances demonstrated great promotion for the growth and Cd uptake of ME. Both plant biomass and Cd concentration significantly increased with the increasing application of the humic substances up to 100 g kg(-1), beyond which no significant change of underground part biomass and Cd concentrations in underground part of A. wardii was observed. The maximum Cd concentration in underground part of ME was 180 mg kg(-1) when 150 g kg(-1) humic substances were applied. The ME showed greater Cd accumulation capability in underground part (0.47-0.68 mg plant(-1)) than that of NME (0.27-0.45 mg plant(-1)). Increasing bioaccumulation coefficient (BCF) values of A. wardii was observed with increasing application of the humic substances. The BCF values of ME were higher than those of NME. However, the use of the humic substances exhibited little impact on translocation factors (TFs) of ME, and the TF values of ME were less than NME. Furthermore, the application of the humic substances improved the remediation factors (RFs) of A. wardii. The RF values in underground part of ME ranging from 0.73 to 0.91 % were apparently higher than those of NME. These results indicated that the humic substances can be a potential candidate for enhancing the phytostabilization of A. wardii grown in Cd-contaminated soils.

Trace elements as contaminants and nutrients: consequences in ecosystems and human health

National Research Council Canada - National Science Library

Prasad, M. N. V. (Majeti Narasimha Vara)

2008-01-01

... for Biomonitoring: Corrections by Use of Electrochemical Ligand Parameters and BCF-Defined Element Clusters 4. Discussion 5. Conclusion References 1 1 6 6 8 10 11 11 14 14 15 18 19 2 Health Implications of T...

COMPUTER-ASSISTED SEMEN ANALYSIS OF RAT SPERMATOZOA AFTER AN INTRAPERITONEAL ADMINISTRATION OF INSECTICIDE DIAZINON

Directory of Open Access Journals (Sweden)

R. TOMAN

2008-05-01

Full Text Available The aim of this study was to reveal the effect of diazinon on the rat spermatozoa motility characteristics using the computer-assisted semen analysis (CASA. Motility, progressive motility, DAP, DCL, DSL, VAP, VCL, VSL, STR, LIN, WOB, ALH, and BCF after the diazinon i.p. administration of 20 mg/kg b.w. were evaluated. 36 hours after the diazinon administration, only slight decrease in VCL, DCL and increase in percentage of progressive motility in the diazinon-treated group. Significant decrease (P<0.01 was only observed in BCF in diazinon-treated group. Computer-assisted semen analysis (CASA of rat sperm motility showed that acute diazinon administration slightly affected the rat sperm motility which can be the first step in the decreased fertilization capacity caused by pesticides. Further investigation of reproductive effects of diazinon is needed.

Biological effects and bioaccumulation of steroidal and phenolic endocrine disrupting chemicals in high-back crucian carp exposed to wastewater treatment plant effluents

International Nuclear Information System (INIS)

Liu Jingliang; Wang Renmin; Huang Bin; Lin Chan; Zhou Jiali; Pan Xuejun

2012-01-01

Endocrine disrupting chemicals (EDCs) found in wastewater treatment plant (WWTP) effluents have been shown to cause adverse effects, but the uptake of EDCs from effluents (measured in fish muscle) are not known. In this study, the biological effects and bioaccumulation of steroidal and phenolic EDCs were assessed in high-back crucian carp (Carassius auratus) exposed to WWTP effluents for 141 days. Compared with fish controls caged in Dianchi Lake, a significant reduction in gonadosomatic index (GSI) and increase in hepatosomatic index (HSI) and plasma vitellogenin (VTG) levels were observed in effluent-exposed fish. The concentrations of steroids and phenols in effluent-exposed fish showed time-dependent increase during the exposure. In addition, bioconcentration factors (BCFs) for steroids and phenols were between 17 and 59 on day 141. The results confirm that steroids and phenols bioconcentrate in fish muscle and this accumulation may account for the biological effects associated with exposures to WWTP effluents. - Highlights: ► We assess the potential risk of WWTP effluents to fish. ► We investigate the biological responses of EDCs in fish exposed to effluents. ► We estimate the uptake of EDCs originating from WWTP effluents in fish. ► The bioaccumulation of EDCs may account for the biological effects of effluents. - Bioaccumulation of endocrine disrupting chemicals in WWTP effluent-exposed fish.

Vegetation response to soil salinity and waterlogging in three saltmarsh hydrosequences through macronutrients distribution

Science.gov (United States)

Ferronato, Chiara; Speranza, Maria; Ferroni, Lucia; Buscaroli, Alessandro; Vianello, Gilmo; Vittori Antisari, Livia

2018-01-01

Saltmarshes consist of soil hydrosequences, where the complex interactions between water tide fluctuations, soil physicochemical properties and plant colonization contribute to the triggering of the pedogenetic processes and consequently to the stability of the saltmarsh edges. In this study, the composition and richness of the vegetation cover were investigated along soil transects in three different saltmarshes. With the aim to investigate the response of the vegetation to the soil hydroperiod and its influence on the availability of soil nutrients, plant and soil samples were collected in four representative sites on each saltmarsh transect (hydrosequence). Among the different species of saltmarshes, L. vulgare and S. europaea colonized intertidal areas, where an accumulation of nutrients (Ca, K, P, S and Na) and organic C and total N (OC and TN, respectively) was found. These intertidal areas are the "critical transition zones", which drive the transition between the terrestrial and the aquatic systems along the increase of soil salinity and water saturation. Among the different element cycles analysed in the soil-plant system, the analysis of the Na and S dynamic, through both bioconcentration and translocation indexes, explains the different adaptation mechanisms to different salinity and waterlogging stressors. The limiting of the species areal was generally associated firstly with a decrease in their Na and S bioconcentration factor and, to a lesser extent, with the increase in their Na and S translocation.

Climate change - An uncertainty factor in risk analysis of contaminated land

International Nuclear Information System (INIS)

Augustsson, Anna; Filipsson, Monika; Oberg, Tomas; Bergbaeck, Bo

2011-01-01

Metals frequently occur at contaminated sites, where their potential toxicity and persistence require risk assessments that consider possible long-term changes. Changes in climate are likely to affect the speciation, mobility, and risks associated with metals. This paper provides an example of how the climate effect can be inserted in a commonly used exposure model, and how the exposure then changes compared to present conditions. The comparison was made for cadmium (Cd) exposure to 4-year-old children at a highly contaminated iron and steel works site in southeastern Sweden. Both deterministic and probabilistic approaches (through probability bounds analysis, PBA) were used in the exposure assessment. Potential climate-sensitive variables were determined by a literature review. Although only six of the total 39 model variables were assumed to be sensitive to a change in climate (groundwater infiltration, hydraulic conductivity, soil moisture, soil:water distribution, and two bioconcentration factors), the total exposure was clearly affected. For example, by altering the climate-sensitive variables in the order of 15% to 20%, the deterministic estimate of exposure increased by 27%. Similarly, the PBA estimate of the reasonable maximum exposure (RME, defined as the upper bound of the 95th percentile) increased by almost 20%. This means that sites where the exposure in present conditions is determined to be slightly below guideline values may in the future exceed these guidelines, and risk management decisions could thus be affected. The PBA, however, showed that there is also a possibility of lower exposure levels, which means that the changes assumed for the climate-sensitive variables increase the total uncertainty in the probabilistic calculations. This highlights the importance of considering climate as a factor in the characterization of input data to exposure assessments at contaminated sites. The variable with the strongest influence on the result was the

Physiologically based modeling of hepatic and gastrointestinal biotransformation in fish

Science.gov (United States)

In fish, as in mammals, the liver generally viewed as the principal site of chemical biotransformation. For waterborne exposures, such as those conducted in support of standardized BCF testing, the effects of hepatic metabolism on chemical accumulation can be simulated using rela...

Fate of 7,12-dimethylbenz(a)anthracene in rainbow trout, Salmo gairdneri

International Nuclear Information System (INIS)

Schnitz, A.R.; Squibb, K.S.; O'Connor, J.M.

1987-01-01

Polycyclic aromatic hydrocarbons (PAH) are contaminants of surface waters and sediments, especially near urban centers. Although aquatic biota accumulate PAHs from environmental sources, metabolism may be rapid, and biota sampled from contaminated areas often have concentrations lower than might be estimated from bioconcentration factors. In some cases PAH metabolism by aquatic biota may create reactive intermediates, some of which have been related to chronic effects in fishes. This report describes the fate and distribution of 7,12-dimethylbenz(a)anthracene (DMBA) after oral administration to rainbows trout (Salmo gairdneri). Emphasis has been placed on the disposition of DMBA among tissues and on DMBA transformation in the hepatobiliary system

Precipitation and air temperature control the variations of dissolved organic matter along an altitudinal forest gradient, Gongga Mountains, China.

Science.gov (United States)

Hu, Zhaoyong; Wang, Genxu; Sun, Xiangyang

2017-04-01

Dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) contribute significantly to C and N cycling in forest ecosystems. Little information is available on the variations in the DOC and DON concentrations and depositions in bulk and stand precipitation within forests along an altitudinal gradient. To determine the temporal variations in the DOC and DON concentrations and depositions in different forests and the spatial variations along the elevation gradient, the DOC and DON concentrations and depositions were measured in bulk precipitation, throughfall, and stemflow within three forest types, i.e., broadleaf forest (BLF), broadleaf-coniferous forest (BCF), and coniferous forest (CF), during the wet season (May to October) on Gongga Mountain, China, in 2015. The concentrations of bulk precipitation in BLF, BCF, and CF were 3.92, 4.04, and 2.65 mg L -1 , respectively, for DOC and were 0.38, 0.26, and 0.29 mg L -1 , respectively, for DON. BCF had the highest DOC deposition both in bulk precipitation (45.12 kg ha -1 ) and stand precipitation (98.52 kg ha -1 ), whereas the highest DON deposition was in BLF (3.62 kg ha -1 bulk precipitation and 4.11 kg ha -1 stand precipitation) during the study period. The meteorological conditions of precipitation and air temperature significantly influenced the dissolved organic matter (DOM) depositions along the elevation gradient. The leaf area index did not show any correlation with DOM depositions during the growing season.

Ændringer i bekæmpelsesmidlernes egenskaber fra 1981-1985 frem til 1996

DEFF Research Database (Denmark)

Clausen, H.

laboratoriet, T50, dage Adsorptionskoefficienten for bindingen til jord, KOC Vandopløseligheden, S, mg pr. liter Fordelingen mellem octanol og vand, KOW Biokoncentrationsfaktoren i fisk, BCF Data for bejdsemidler er ikke medtaget i analysen, da disse ikke indgår i behandlingshyppigheden. Belastningstal...

An exploratory investigation of various modes of action and potential adverse outcomes of fluoxetine in marine mussels

International Nuclear Information System (INIS)

Franzellitti, Silvia; Buratti, Sara; Capolupo, Marco; Du, Bowen; Haddad, Samuel P.; Chambliss, C. Kevin; Brooks, Bryan W.; Fabbri, Elena

2014-01-01

Highlights: • Mode of action (MOA) related endpoints and biomarkers of toxicity were assessed in mussels exposed to fluoxetine (FX). • Significant FX bioaccumulation was observed in tissues of mussels exposed to 30 and 300 ng/L FX. • Alterations of cAMP-related cell signaling were observed in exposed mussels as part of the MOA of FX. • FX reduced the health status of mussels inducing lysosomal effects in digestive gland and antioxidant responses in gills. • The importance of considering additional MOAs and adverse outcome pathways for FX impacts on mussels is highlighted. - Abstract: The present study investigated possible adverse outcome pathways (AOPs) of the antidepressant fluoxetine (FX) in the marine mussel Mytilus galloprovincialis. An evaluation of molecular endpoints involved in modes of action (MOAs) of FX and biomarkers for sub-lethal toxicity were explored in mussels after a 7-day administration of nominal FX concentrations encompassing a range of environmentally relevant values (0.03–300 ng/L). FX bioaccumulated in mussel tissues after treatment with 30 and 300 ng/L FX, resulting in bioconcentration factor (BCF) values ranging from 200 to 800, which were higher than expected based solely on hydrophobic partitioning models. Because FX acts as a selective serotonin (5-HT) re-uptake inhibitor increasing serotonergic neurotransmission at mammalian synapses, cell signaling alterations triggered by 5-HT receptor occupations were assessed. cAMP levels and PKA activities were decreased in digestive gland and mantle/gonads of FX-treated mussels, consistent with an increased occupation of 5-HT1 receptors negatively coupled to the cAMP/PKA pathway. mRNA levels of a ABCB gene encoding the P-glycoprotein were also significantly down-regulated. This membrane transporter acts in detoxification towards xenobiotics and in altering pharmacokinetics of antidepressants; moreover, it is under a cAMP/PKA transcriptional regulation in mussels. Potential stress

An exploratory investigation of various modes of action and potential adverse outcomes of fluoxetine in marine mussels

Energy Technology Data Exchange (ETDEWEB)

Franzellitti, Silvia, E-mail: silvia.franzellitti@unibo.it [University of Bologna, Interdepartment Centre for Environmental Science Research, via S. Alberto 163, 48123 Ravenna (Italy); University of Bologna, Department of Biological, Geological, and Environmental Sciences, via Selmi 3, 40100 Bologna (Italy); Buratti, Sara; Capolupo, Marco [University of Bologna, Interdepartment Centre for Environmental Science Research, via S. Alberto 163, 48123 Ravenna (Italy); Du, Bowen; Haddad, Samuel P. [Department of Environmental Science, Baylor University, Waco, TX 76798 (United States); Chambliss, C. Kevin [Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798 (United States); Brooks, Bryan W. [Department of Environmental Science, Baylor University, Waco, TX 76798 (United States); Fabbri, Elena [University of Bologna, Interdepartment Centre for Environmental Science Research, via S. Alberto 163, 48123 Ravenna (Italy); University of Bologna, Department of Biological, Geological, and Environmental Sciences, via Selmi 3, 40100 Bologna (Italy)

2014-06-01

Highlights: • Mode of action (MOA) related endpoints and biomarkers of toxicity were assessed in mussels exposed to fluoxetine (FX). • Significant FX bioaccumulation was observed in tissues of mussels exposed to 30 and 300 ng/L FX. • Alterations of cAMP-related cell signaling were observed in exposed mussels as part of the MOA of FX. • FX reduced the health status of mussels inducing lysosomal effects in digestive gland and antioxidant responses in gills. • The importance of considering additional MOAs and adverse outcome pathways for FX impacts on mussels is highlighted. - Abstract: The present study investigated possible adverse outcome pathways (AOPs) of the antidepressant fluoxetine (FX) in the marine mussel Mytilus galloprovincialis. An evaluation of molecular endpoints involved in modes of action (MOAs) of FX and biomarkers for sub-lethal toxicity were explored in mussels after a 7-day administration of nominal FX concentrations encompassing a range of environmentally relevant values (0.03–300 ng/L). FX bioaccumulated in mussel tissues after treatment with 30 and 300 ng/L FX, resulting in bioconcentration factor (BCF) values ranging from 200 to 800, which were higher than expected based solely on hydrophobic partitioning models. Because FX acts as a selective serotonin (5-HT) re-uptake inhibitor increasing serotonergic neurotransmission at mammalian synapses, cell signaling alterations triggered by 5-HT receptor occupations were assessed. cAMP levels and PKA activities were decreased in digestive gland and mantle/gonads of FX-treated mussels, consistent with an increased occupation of 5-HT1 receptors negatively coupled to the cAMP/PKA pathway. mRNA levels of a ABCB gene encoding the P-glycoprotein were also significantly down-regulated. This membrane transporter acts in detoxification towards xenobiotics and in altering pharmacokinetics of antidepressants; moreover, it is under a cAMP/PKA transcriptional regulation in mussels. Potential stress

Evaluating the coalbed methane potential of the Gething coals in NE British Columbia, Canada: An example from the Highhat area, Peace River coalfield

International Nuclear Information System (INIS)

Gentzis, Thomas; Schoderbek, David; Pollock, Sharlene

2006-01-01

Lower Cretaceous coals from the Gething Formation in the Highhat area of NE British Columbia were analyzed for gas content as part of an exploration program. Samples of continuous wireline core and cuttings were processed. Vitrinite reflectance and dry ash-free volatile matter both indicate that the rank of the coal is low volatile bituminous. The coals are well cleated and contain shear fractures, as seen in the core description and in the FMI logs. Coal cuttings were screened to remove a very fine fraction (-200 mesh) and then treated in heavy liquid (SG 1.75 g/cm 3 ) to remove inorganic lithologies. For the cores, total gas content ranges from 516.9 to 876.8 scf/t (16.1-27.4 cm 3 /g; adb) with a mean value of 671.1 scf/t (20.9 cm 3 /g) at 20.5% ash (adb). For the cuttings, all desorbed gas was assigned to the +200 mesh/float 1.75 SG weight fraction. On this recalculated basis, total gas content for the processed cuttings ranges from 651.8 scf/t (20.4 cm 3 /g) to a high value of 2083.6 scf/t (65.1 cm 3 /g; adb). Weight yields after screening/floating are generally low. For samples yielding very low values ( 3 /g; adb) with a mean value of 760.4 scf/t (23.8 cm 3 /g) at 15.5% ash (adb). The desorbed gas is predominantly methane (98-99%; air-free and acid-free basis) and average carbon dioxide is about 6%. Methane is thermogenic based on isotopic analysis. Methane adsorption isotherm analysis at reservoir conditions shows that the Gething coals are at least 95% gas saturated. Using 1300 m as a depth cut-off and an average gas content of 672 scf/t (21 cm 3 /g), GIP (gas-in-place) in the Highhat prospect area is estimated to be 270 bcf (billion cubic feet). This translates to 24.5 bcf/section (a section is equal to a square mile or 640 acres) for the 11 sections of land in the vicinity of the corehole or to 3 bcf/m/mile 2 . The low absolute permeability of the coals (0.5 md) is the main limiting factor for producibility and commercial development of the resource. Even

76 FR 2093 - Eni USA Gas Marketing LLC; Application for Blanket Authorization To Export Liquefied Natural Gas

Science.gov (United States)

2011-01-12

... Authorization To Export Liquefied Natural Gas AGENCY: Office of Fossil Energy, DOE. ACTION: Notice of...), requesting blanket authorization to export liquefied natural gas (LNG) that previously had been imported into... (Bcf) of natural gas. The LNG would be exported from the Cameron LNG Terminal (Cameron Terminal), owned...

Accumulation of elements by edible mushroom species II. A comparison of aluminium, barium and nutritional element contents.

Science.gov (United States)

Mleczek, Mirosław; Siwulski, Marek; Stuper-Szablewska, Kinga; Sobieralski, Krzysztof; Magdziak, Zuzanna; Goliński, Piotr

2013-01-01

The aim of the study was to compare accumulation efficiency of Al, Ba and nutritional elements (Ca, Fe, K, Mg, Mn, Na) exhibited by six edible mushrooms collected in particular regions of Poland during the last 20 years. The studied mushroom species were Boletus edulis, Cantharellus cibarius, Lactarius deliciosus, Leccinum aurantiacum, Suillus luteus and Xerocomus badius. The highest and the lowest concentrations of the elements in tested mushroom species were 11 - 410, 34 - 337, 16785 - 34600, 140 - 607, 12 - 75 and 16 - 143 mg kg(-1)d.m., respectively. The highest average concentrations of Al, Mg and Mn were observed in Suillus luteus fruiting bodies, while for Ba, Ca, K and Na it was in Lactarius deliciosus. BCF >1 was found for K and Mg in all tested mushroom species and additionally for the highest Ca and Na concentrations of all tested mushroom species except for C. cibarius and S. luteus, respectively. For the other tested elements (Al, Ba, Fe and Mn) BCF values < 1 were recorded.

Cellular oncogene expression following exposure of mice to γ-rays

International Nuclear Information System (INIS)

Anderson, A.; Woloschak, G.E.

1991-01-01

We examined the effects of total body exposure of BCF1 mice to γ-rays (300 cGy) in modulating expression of cellular oncogenes in both gut and liver tissues. We selected specific cellular oncogenes (c-fos, c-myc, c-src, and c-H-ras), based on their normal expression in liver and gut tissues from untreated mice. As early as 5 min. following whole body exposure of BCF1 mice to γ-rays we detected induction of mRNA specific for c-src and c-H-ras in both liver and gut tissues. c-fos RNA was slightly decreased in accumulation in gut but was unaffected in liver tissue from irradiated mice relative to untreated controls. c-myc mRNA accumulation was unaffected in all tissues examined. These experiments document that modulation of cellular oncogene expression can occur as an early event in tissues following irradiation and suggest that this modulation may play a role in radiation-induced carcinogenesis

Mercury in mushrooms and soil from the Wieluńska Upland in south-central Poland.

Science.gov (United States)

Falandysz, Jerzy; Bielawski, Leszek; Kawano, Masabide; Brzostowski, Andrzej; Chudzyński, Krzysztof

2002-09-01

Concentrations of mercury were determined in the fruiting bodies of 15 species of higher mushrooms and underlying soil substrate collected from Wieluńska Upland in northern part of Sandomierska Valley in south-central Poland in 1995. A total of 197 samples of caps, 197 stalks, 30 whole fruiting bodies and 227 soil (0-10 cm layer) were analyzed. Mean mercury concentrations in soil substrate corresponding to 15 mushroom species were between 28 +/- 17 and 85 +/- 62 ng/g dry matter (total range between 3.0-190 ng/g). The average cap to stalk concentration quotients of Hg were around 2 (range between 1.1 +/- 1.1 and 2.8 +/- 1.4). However, this quotient in Larch bolete (Suillus grevillei) was 4.4 +/- 6.3. Concentrations of Hg varied depending on the mushroom species. Parasol Mushroom (Macrolepiota procera) and Horse mushroom (Agaricus arvensis) contained the greatest mean mercury concentrations both in caps (between 4500 +/- 1700 and 4400 +/- 2400 ng/g dry matter) and stalks (between 2800 +/- 1300 and 3000 +/- 2000 ng/g dry matter). Both the Parasol Mushroom and Horse mushroom were characterised also by a greater potential to bioconcentrate mercury from soils as evidenced by great bioconcentration factors (BCFs), which were between 170 +/- 160 and 130 +/- 120 for caps, and 110 +/- 97 and 89 +/- 92 for stalks. Mercury concentrations in caps and stalks of False death cap (Amanita citrina) increased (p Suillus luteus).

Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure

Energy Technology Data Exchange (ETDEWEB)

Barillet, Sabrina, E-mail: sabrina.barillet@free.f [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.f [Laboratory of Radioecology and Ecotoxicology, IRSN (Institute for Radiological protection and Nuclear Safety), DEI/SECRE/LRE, Cadarache, Bat 186, BP 3, 13115 St-Paul-Lez-Durance cedex (France); Palluel, Olivier, E-mail: olivier.palluel@ineris.f [Ecotoxicological Risk Assessment Unit, INERIS (National Institute for Industrial Environment and Risks), Parc technologique ALATA, 60 550 Verneuil-en-Halatte (France); Porcher, Jean-Marc, E-mail: jean-marc.porcher@ineris.f [Ecotoxicological Risk Assessment Unit, INERIS (National Institute for Industrial Environment and Risks), Parc technologique ALATA, 60 550 Verneuil-en-Halatte (France); Devaux, Alain, E-mail: alain.devaux@entpe.f [Universite de Lyon, INRA, EFPA-SA, Environmental Science Laboratory (LSE), ENTPE, 69518 Vaulx en Velin cedex (France)

2011-02-15

Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose-response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect. - Research highlights: Depleted U bioconcentration factor is of about 1000 in zebrafish exposed to 20 {mu}g/L. Hepatic antioxidant disorders are noticed as soon as the first hours of exposure. DNA damage is induced in red blood cells after 20 d of exposure to 500 {mu}g DU/L. The brain cholinergic system (AChE activity) is impacted. - This study demonstrates that U is highly bioaccumulated in fish, resulting in biological disorders such as hepatic oxidative stress as well as genotoxic and neurotoxic events.

Molecular effects and bioaccumulation of levonorgestrel in the non-target organism Dreissena polymorpha

International Nuclear Information System (INIS)

Contardo-Jara, Valeska; Lorenz, Claudia; Pflugmacher, Stephan; Nuetzmann, Gunnar; Kloas, Werner; Wiegand, Claudia

2011-01-01

Bioaccumulation and effects of the contraceptive hormone levonorgestrel were examined in the non-target organism Dreissena polymorpha. Molecular biomarkers of biotransformation, elimination, antioxidant defence and protein damage were analyzed after exposure to increasing concentrations of levonorgestrel in a flow-through system. The lowest concentration (0.312 μg L -1 ) was 100-fold bioconcentrated within four days. A decrease of the bioconcentration factor was observed within one week for the highest test concentrations (3.12 and 6.24 μg L -1 ) suggesting enhanced excretory processes. The immediate mRNA up-regulation of pi class glutathione S-transferase proved that phase II biotransformation processes were induced. Disturbance of fundamental cell functions was assumed since the aryl hydrocarbon receptor has been permanently down-regulated. mRNA up-regulation of P-glycoprotein, superoxide dismutase and metallothioneine suggested enhanced elimination processes and ongoing oxidative stress. mRNA up-regulation of heat shock protein 70 in mussels exposed to the two highest concentrations clearly indicated impacts on protein damage. - Fundamental cell processes as biotransformation, elimination and prevention from oxidative stress are influenced by exposure of the contraceptive levonorgestrel in non-target organisms. - Research highlights: → Bioaccumulation of levonorgestrel in mussels is higher than expected based on its lipophilicity. → Exposure to levonorgestrel causes oxidative stress and enhanced elimination processes. → Glutathione S-transferase (pi class) mRNA induction after one day hint on phase II biotransformation. → mRNA induction of heat shock protein 70 after one week prove protein damage.

Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure

International Nuclear Information System (INIS)

Barillet, Sabrina; Adam-Guillermin, Christelle; Palluel, Olivier; Porcher, Jean-Marc; Devaux, Alain

2011-01-01

Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose-response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect. - Research highlights: → Depleted U bioconcentration factor is of about 1000 in zebrafish exposed to 20 μg/L. → Hepatic antioxidant disorders are noticed as soon as the first hours of exposure. → DNA damage is induced in red blood cells after 20 d of exposure to 500 μg DU/L. → The brain cholinergic system (AChE activity) is impacted. - This study demonstrates that U is highly bioaccumulated in fish, resulting in biological disorders such as hepatic oxidative stress as well as genotoxic and neurotoxic events.

Concentration parameters for radionuclides by marine molluscs

International Nuclear Information System (INIS)

Nakahara, Motokazu; Makamura, Ryoichi; Suzuki, Yuzuru; Matsuba, Mitsue

1994-01-01

Accumulation of radionuclides from seawater and from food by marine molluscs was observed in the laboratory experiments to get bioconcentration parameters for the nuclides. The radionuclides investigated were 57 Co, 95m Tc, 103 Ru, 137 Cs, 65 Zn and 54 Mn. Several species of molluscs containing pelecypods, gastropods and cephalopod were used for the experimental organisms. For the uptake experiment from seawater, the organisms were kept for more than seven days in radioactive seawater containing those radionuclides together. Then the organisms were transferred into nonradioactive seawater to observe the loss of the nuclides from the organisms. Biphasic loss curves were observed for all of the nuclides. Bioconcentration parameters, such as uptake rate, excretion rate, biological half-life and concentration factor at steady state were estimated from the uptake and excretion curves of the nuclides by the organisms by applying an exponential model. In the uptake experiments from radioactive food, the phytoplankton (Tetraselmis tetrathele), the brown algae (Eisenia bicyclis) and the viscera of abalone (Haliotis discus) were fed to bivalves, herbivorous gastropods and carnivorous molluscs, respectively. After single feeding of the labelled food with the nuclides, retention of the nuclides in whole body of the organisms was followed for several weeks or more. The organisms showed relatively high retention of the nuclides in whole body, except 137 Cs and 54 Mn. Retention of 137 Cs and 54 Mn in the organisms one day after feeding of radioactive food was lower than 25% of the radioactivity dosed. (author)

Concentration of radionuclides by marine organisms and their food chain

International Nuclear Information System (INIS)

Nakahara, Motokazu

1993-01-01

Accumulation of radionuclides from seawater and from food by marine organisms was observed in the laboratory experiments to get bioconcentration parameters for the nuclides. The radionuclides investigated were 57 Co, 95m Tc, 103 Ru, 137 Cs, 65 Zn and 54 Mn. Several species of molluscs containing pelecypods, gastropods and cephalopod were used for the experimental organisms. For the uptake experiment from seawater, the organisms were kept for more than seven days in radioactive seawater containing those radionuclides together. Then the organisms were transferred into non-radioactive seawater to observe the loss of the nuclides from the organisms. Biphasic loss curves were observed for all of the nuclides. Bioconcentration parameters, such as uptake rate, excretion rate, biological half-life and concentration factor at steady state were estimated from the uptake and excretion curves of the nuclides by the organisms by applying an exponential model. In the uptake experiments from radioactive food, the phytoplankton (Tetraselmis tetrathele), the brown algae (Eisenia bicyclis) and the viscera of abalone were fed to bivalves, herbivorous gastropods and carnivorous molluscs, respectively. After single feeding of the labelled food with the nuclides, retention of the nuclides in whole body of the organisms was followed for several weeks or more. The organisms showed relatively high retention of the nuclides in whole body, except 137 Cs and 54 Mn. Retention of 137 Cs and 54 Mn in the organisms one day after feeding of radioactive food was lower than 25 % of the radioactivity dosed. (author)

Ecotoxicity studies in Jamaican environment I. Toxicity, bioaccumulation, elimination and tissue partitioning of ethoprophos by the fish Tilapia in brackish water microcosm

International Nuclear Information System (INIS)

Robinson, D.E.; Mansingh, A.

1999-01-01

The present study was conducted on the toxicity of ethoprophos to sexually mature red hybrid Tilapia. The NOEC and LOEC were 1 and 4 mg/L of ethoprophos; the 24-h LC 50 and LC 95 values were 8.41 and 21.00 mg/L. Bioconcentration of the insecticide from NOEC and LOEC in the surrounding water by the fish peaked (3.25'' 0.412 and 12.50'' 1.831 μg/g, respectively) eight to twelve hours after exposure. Bioconcentration from LOEC was 3.8-fold greater than at NOEC. The contaminated fish (after 24-h exposure to LOEC) eliminated 83% of the ethoprophos residues within 12-h exposure to uncontaminated water. The order of partitioning of ethoprophos in the different tissues of the fish was gonads > liver > gut > gills > skin-muscle-bone. (author)

Study of the potential of barnyard grass for the remediation of Cd- and Pb-contaminated soil.

Science.gov (United States)

Xu, Jianling; Cai, Qiongyao; Wang, Hanxi; Liu, Xuejun; Lv, Jing; Yao, Difu; Lu, Yue; Li, Wei; Liu, Yuanyuan

2017-05-01

In this study, the microwave digestion method was used to determine total cadmium (Cd) and lead (Pb) concentrations, the BCR method was used to determine different states of Cd and Pb, and atomic absorption spectroscopy (AAS) and inductively coupled plasma optical emission spectrometry (ICP-OES) were used to determine Cd and Pb concentrations in simulated soil and barnyard grass before and after planting barnyard grass to provide a theoretical basis for the remediation of Cd- and Pb-contaminated soil. The results showed that the bioconcentration factor changes with different Cd concentrations are relatively complex and that the removal rate increases regularly. The 100 mg kg -1 Cd treatment had the highest removal rate, which reached 36.66%. For Pb, the bioconcentration factor decreased and tended to reach equilibrium as the Pb concentration increased. The highest removal rate was 41.72% and occurred in the 500 mg kg -1 Pb treatment; however, this removal rate was generally lower than that of Cd. In addition, the reduction state had the highest change rate, followed by the residual, acid soluble and oxidation states. For Pb, the residual state has the highest change rate, followed by the acid soluble state, reduction state and oxidation state. In addition, a significant correlation was observed between the soil Pb and Cd concentrations and the concentrations of Pb and Cd that accumulated in the belowground biomass of the barnyard grass, but no significant correlation was observed between the soil Pb and Cd concentrations and the amounts of Pb and Cd that accumulated in the aboveground biomass of the barnyard grass. The highest transfer factor of Cd was 0.49, which occurred in the 5 mg kg -1 Cd treatment. The higher transfer factor of Pb was 0.48 in the 100 mg kg -1 Pb treatment. All of these factors indicate that the belowground biomass of barnyard grass plays a more important role in the remediation of Cd- and Pb-contaminated soils than the aboveground

Subcellular localization of cadmium in the root cells of Allium cepa ...

Indian Academy of Sciences (India)

Unknown

showed that significantly higher level of Cd in vacuoles existed in the vacuolar precipitates of meristematic or ... containers by dipping the base in half Hoagland's nutrient ..... Greger M 1999 Metal availability and bioconcentration in plants;.

Thallium, uranium, and 235U/238U ratios in the digestive gland of American lobster (Homarus americanus) from an industrialized harbor

International Nuclear Information System (INIS)

Chou, C.L.; Uthe, J.F.

1995-01-01

Only a few studies have concentrated on elements such as thallium (TI). Uranium (U) has been studied as a radionuclide of concern in food and the environment. Foodstuffs contain 10-100 ng U· -1 with vegetables and cereals contributing most heavily to the daily intake of ca 1.5 ug U. Between 10-30% of ingested U is absorbed, with most being stored in bone. Rainbow trout (onchorynchus mykiss) and longnose sucker (Catostomus catostomus) from a lake with naturally high radioactivity contained -1 in the flesh. Trout bone contained 40 ng U·g -1 . Higher tissue U concentrations occurred in fish from areas receiving U mining wastes. Bioconcentration factors for bone and flesh were estimated to be low, 118 and 14.7, respectively. This paper describes the Inductively coupled plasma-mass spectrometry (ICP-MS) determination of Tl and U in digestive gland tissue from lobsters captured in the vicinity of Belledune Harbor, New Brunswick, Canada. The harbor is the site of a lead smelter, a fertilizer plant, and a coal-fired power station (the latter due to enter production in late 1993) and thus has the potential of adding significant amounts of Tl to the local marine environment. The accumulation of Tl from water by marine shellfish is low, at least for bivalves, and the accumulated Tl is eliminated in a number of days when the animals are transferred to clean water. Bioconcentration factors for U in finfish ranged from 0.4-17 for larger species. However, because of the high concentrations of various trace elements in lobster digestive gland, its desirability as a foodstuff, and its relatively large size (approximately 20% of the edible tissue yield), we have investigated Tl and U concentrations and 235U / 238U ratios in it. 15 refs., 1 fig., 3 tabs

Presentation of a general algorithm for effect-assessment on secondary poisoning. II Terrestrial food chains

NARCIS (Netherlands)

Romijn CAFM; Luttik R; Slooff W; Canton JH

1991-01-01

In an earlier report, a simple algorithm for effect-assessment on secondary poisoning of birds and mammals was presented. This algorithm (MAR = NOEC/BCF) was drawn up by analyzing an aquatic food chain. In the present study it was tested whether this algorithm can be used equally well for

Bioconcentração e biomagnificação de metilmercúrio na baía de Guanabara, Rio de Janeiro

Directory of Open Access Journals (Sweden)

Helena A. Kehrig

2011-01-01

Full Text Available Methylmercury was determined in water and aquatic biota from Guanabara Bay. Trophic transfer of methylmercury was observed between trophic levels from prey (microplankton, mesoplankton and fish with different feeding habits to top predator (pelagic demersal fish. Top predator fish presented the highest methylmercury concentrations (320.3 ± 150.7 mg kg-1 dry wt., whereas microplankton presented the lowest (8.9 ± 3.3 mg kg-1 dry wt.. The successive amplification of methylmercury concentrations and its bioconcentration factor with increasing trophic levels from base to top indicate that biomagnification may be occurring along the food web. Results suggest the importance of feeding habits and trophic level in the bioaccumulation of methylmercury by aquatic biota.

Intestinal parasite Acanthocephalus lucii (Acanthocephala) from European perch (Perca fluviatilis) as a bioindicator for lead pollution in the stream "Jevanský potok" near Prague, Czech Republic.

Science.gov (United States)

Jankovská, Ivana; Miholová, Daniela; Petrtýl, Miloslav; Romočuský, Stěpán; Kalous, Lukáš; Vadlejch, Jaroslav; Cadková, Zuzana; Langrová, Iva

2011-03-01

Lead concentrations in the tissues of perch and its parasites were determined as mg/kg dw. Lead was found at higher concentrations in the acanthocephalans (11.56) than in different tissues (liver, gonads and muscle with skin and bone) of perch. With respect to fish tissues, the highest concentrations of lead were present in the liver (1.24), followed by the gonads (0.57) whereas the lowest concentrations were in the muscle with skin and bone (0.21). The bioconcentration factors for lead indicated that parasites accumulate metals to a higher degree than fish tissues--lead concentrations in acanthocephalans were 9.32, 19.27 and 55.05 higher than in liver, gonads and muscles of host, respectively.

182W and HSE constraints from 2.7 Ga komatiites on the heterogeneous nature of the Archean mantle

Science.gov (United States)

Puchtel, Igor S.; Blichert-Toft, Janne; Touboul, Mathieu; Walker, Richard J.

2018-05-01

While the isotopically heterogeneous nature of the terrestrial mantle has long been established, the origin, scale, and longevity of the heterogeneities for different elements and isotopic systems are still debated. Here, we report Nd, Hf, W, and Os isotopic and highly siderophile element (HSE) abundance data for the Boston Creek komatiitic basalt lava flow (BCF) in the 2.7 Ga Abitibi greenstone belt, Canada. This lava flow is characterized by strong depletions in Al and heavy rare earth elements (REE), enrichments in light REE, and initial ε143Nd = +2.5 ± 0.2 and intial ε176Hf = +4.2 ± 0.9 indicative of derivation from a deep mantle source with time-integrated suprachondritic Sm/Nd and Lu/Hf ratios. The data plot on the terrestrial Nd-Hf array suggesting minimal involvement of early magma ocean processes in the fractionation of lithophile trace elements in the mantle source. This conclusion is supported by a mean μ142Nd = -3.8 ± 2.8 that is unresolvable from terrestrial standards. By contrast, the BCF exhibits a positive 182W anomaly (μ182W = +11.7 ± 4.5), yet is characterized by chondritic initial γ187Os = +0.1 ± 0.3 and low inferred source HSE abundances (35 ± 5% of those estimated for the present-day Bulk Silicate Earth, BSE). Collectively, these characteristics are unique among Archean komatiite systems studied so far. The deficit in the HSE, coupled with the chondritic Os isotopic composition, but a positive 182W anomaly, are best explained by derivation of the parental BCF magma from a mantle domain characterized by a predominance of HSE-deficient, differentiated late accreted material. According to the model presented here, the mantle domain that gave rise to the BCF received only ∼35% of the present-day HSE complement in the BSE before becoming isolated from the rest of the convecting mantle until the time of komatiite emplacement at 2.72 Ga. These new data provide strong evidence for a highly heterogeneous Archean mantle in terms of absolute

Control of damping-off of organic and conventional cucumber with extracts from a plant-associated bacterium rivals a seed treatment pesticide

Science.gov (United States)

Environmentally friendly control measures are needed for soilborne diseases of crops grown in organic and conventional production systems. We tested ethanol extracts from cultures of Serratia marcescens N4-5 and N2-4, Burkholderia cepacia BC-1 and BC-2, and B. ambifaria BC-F for control of damping-o...

Time-resolved plastic scintillator dosimetry in a dynamic thorax phantom

DEFF Research Database (Denmark)

Sibolt, Patrik; Andersen, Claus E.; Ottosson, Wiviann

2017-01-01

in a lung. The phantom motion was controlled by a script in-house developed using LabVIEW (National Instruments) and synchronized with the in-house developed ME40 scintillator dosimetry system (DTU Nutech). The dose in the center of the tumor was measured, using a BCF-60 plastic scintillator detector (Saint...

An exploration of the relationship between adsorption and bioavailability of pesticides in soil to earthworm

International Nuclear Information System (INIS)

Yu Yunlong; Wu Xiaomao; Li Shaonan; Fang Hua; Zhan Haiyan; Yu Jingquan

2006-01-01

A study was conducted to determine the adsorption/desorption of butachlor, myclobutanil and chlorpyrifos on five soils using a batch equilibration technique and to study the relationship between bioavailability to Allolobophora caliginosa and the adsorption/desorption of these three pesticides. The results showed that the adsorption/desorption processes of the tested compounds were mainly controlled by soil organic matter content (OM) and octanol/water-partitioning coefficient (K ow ), and that the bioavailability of the pesticides was dependent on characteristics of pesticides, properties of soils, and uptake routes of earthworms. Bioconcentration of butachlor and myclobutanil was negatively correlated with Freundlich adsorption constant K af and K df . However, only a slightly positive correlation between bioconcentration and K af and K df was observed for chlorpyrifos due to its high affinity onto soil. - Bioavailability of pesticides in soil to earthworm is governed by adsorption characteristics

Instrumental neutron activation analysis to determine inorganic elements in paddy soil and rice and evaluate bioconcentration factors in rice

Directory of Open Access Journals (Sweden)

Prapamon Seeprasert

2017-06-01

Full Text Available Increased anthropogenic activity, especially in thriving industries and mining activity, has led to the accumulation of inorganic elements in the soil. This study applied neutron activation analysis for the determination of inorganic element concentrations in paddy soils and quantified the nutrient value of paddy rice cultivated on various agricultural sites throughout Thailand. The determination accuracy of the elements—U, As, Sb, W, Mn, K, La, Cr, Hf, Cs, Sc, Fe, Co, Cd and Zn was assessed using National Institute of Standards and Technology standard reference materials; the results were satisfactory, showing low relative error. High analytical precision was also observed. Cadmium was selected to check the linearity of the calibration curve against a Cd standard. For a calibration curve in the range 1–9 μg, a correlation coefficient of 0.997 was found. Trace amounts of U, As, Sb, W, Mn, K, La, Cr, Hf, Cs, Sc, Fe, Co, Zn and Cd were also found in the soil samples. However, the Co, Cd, and Zn concentrations were especially high in agricultural sites in Tak province. The elemental concentrations in rice followed the order K > Zn > Mn. The data obtained are of potential benefit for the development of trace element supplementation in food.

Determination of γ-rays emitting radionuclides in surface water: application of a quantitative biosensing method

International Nuclear Information System (INIS)

Wolterbeek, H. Th.; Van der Meer, A. J. G. M.

1995-01-01

A quantitative biosensing method has been developed for the determination of γ-rays emitting radionuclides in surface water. The method is based on the concept that at equilibrium the specific radioactivity in the biosensor is equal to the specific radioactivity in water. The method consists of the measurement of both the radionuclide and the related stable isotope (element) in the biosensor and the determination of the element in water. This three-way analysis eliminates problems such as unpredictable biosensor behaviour, effects of water elemental composition or further abiotic parameters on accumulation levels: what remains is the generally high enrichment (bioaccumulation factor BCF) of elements and radionuclides in the biosensor material. Using water plants, the method is shown to be three to five orders of magnitude more sensitive than the direct analysis of water. (author)

Determination of {gamma}-rays emitting radionuclides in surface water: application of a quantitative biosensing method

Energy Technology Data Exchange (ETDEWEB)

Wolterbeek, H Th; Van der Meer, A. J. G. M. [Delft University of Technology, Interfaculty Reactor Institute, Mekelweg 15, 2629 JB Delft (Netherlands)

1995-12-01

A quantitative biosensing method has been developed for the determination of {gamma}-rays emitting radionuclides in surface water. The method is based on the concept that at equilibrium the specific radioactivity in the biosensor is equal to the specific radioactivity in water. The method consists of the measurement of both the radionuclide and the related stable isotope (element) in the biosensor and the determination of the element in water. This three-way analysis eliminates problems such as unpredictable biosensor behaviour, effects of water elemental composition or further abiotic parameters on accumulation levels: what remains is the generally high enrichment (bioaccumulation factor BCF) of elements and radionuclides in the biosensor material. Using water plants, the method is shown to be three to five orders of magnitude more sensitive than the direct analysis of water. (author)

Subcellular localization of Cd in the root cells of Allium sativum by ...

Indian Academy of Sciences (India)

Unknown

Cd. High amounts of Cd were mainly accumulated in the vacuoles and nucleoli of cortical cells in differentiat- ing and ... The bulbs were germinated, and grown in 3 containers ..... Greger M 1999 Metal availability and bioconcentration in plants ...

High pressure processing of bivalve shellfish and HPP's potential use as a virus intervention

Science.gov (United States)

Bivalve shellfish readily bioconcentrate pathogenic microbes and substance, such as algal and dinoflagulate toxins, fecal viruses and bacteria, and naturally present vibrio bacteria. High pressure processing (HPP) is currently used as an intervention for Vibrio vulnificus bacteria within molluscan ...

Seasonal study on Bothriocephalus as indicator of metal pollution in ...

African Journals Online (AJOL)

... vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, selenium, molybdenum, cadmium, tin, antimony, tellurium, barium, mercury, thallium, lead and uranium) were determined with an ICP-MS. Bioconcentration of metals (selenium, mercury, and lead during autumn; copper, zinc, selenium, cadmium, ...

Customer service drives pipelines' reorganization

International Nuclear Information System (INIS)

Share, J.

1997-01-01

The concept behind formation of Enron Transportation and Storage tells plenty about this new gas industry. When executives at the Enron Gas Pipeline Group considered plans last year to streamline operations by merging the support functions of Transwestern Pipeline and their other wholly owned pipeline company, Northern Natural Gas, seamless customer service was foremost on their agenda. Instead of worrying about whether employees would favor one pipeline over the other, perhaps to the detriment of customers, they simply created a new organization that everyone would swear the same allegiance to. The 17,000-mile, 4.1 Bcf/d Northern system serves the upper Midwest market and two major expansion projects were completed there last year. Transwestern is a 2,700-mile system with an eastward capacity of 1 Bcf/d and westward of 1.5 Bcf/, that traditionally served California markets. It also ties into Texas intrastate markets and, thanks to expansion of the San Juan lateral, to southern Rocky Mountain supplies. Although Enron Corp. continues to position itself as a full-service energy company, the Gas Pipeline Group continues to fuel much of corporate's net income, which was $584 million last year. With ET and S comprising a significant portion of GPG's income, it was vital that the merger of Northern's 950 employees with Transwestern's 250 indeed be a seamless one. It was not easy either psychologically or geographically with main offices in Omaha, NE and Houston as well as operations centers in Minneapolis, MN; Amarillo, TX; W. Des Moines, IA; and Albuquerque, NM. But the results have been gratifying, according to William R. Cordes, President of ET and S and Nancy L. Gardner, Executive Vice President of Strategic Initiatives

Alliance opens for business boosted by EIA forecast

Energy Technology Data Exchange (ETDEWEB)

Jaremko, G.

2000-12-04

The Energy Information Administration (EIA) of the US Department of Energy recently released a new forecast showing US requirements for natural gas growing at a steady pace. By 2020, EIA says, pipeline imports will have climbed by 70 per cent to 5.8 Tcf per year. Tanker imports of natural gas liquids are also set to grow at the rate of 700 bcf annually by 2020. Much of the demand growth is expected to continue to be driven by the expanding use of natural gas in electricity generation, but there are across-the-board increases forecast in US residential, commercial and industrial gas consumption as well, thanks to a predicted overall economic growth of an average three per cent annually. If these predictions materialize, the initial excess pipeline capacity created by the Alliance Pipeline will shrink very quickly. Accordingly, the next major development spawned by Alliance, the Millenium Pipeline Project, an international effort which involves TransCanada Pipelines and Union Gas, as well as the Columbia Energy Group in the US, is expected to move ahead. A target of 2002 is set for the proposed 700 mmcf per day route across Lake Erie to New York State to New York City. In addition to Alliance, there is TransCanada Pipelines' 1.1 bcf per day new capacity added by the Foothills-Northern Border export route. Overall, an average of 1.0 bcf per day of excess capacity is predicted which will, however, last no more than two to five years. The EIA expects that new projects in Alaska and the Northwest Territories will soak up the excess capacity and set off a new round of expansion by the Canadian pipeline system.

Classical gas: Hearty prices, robust demand combine to pump breezy optimism through 2005 forecasts

International Nuclear Information System (INIS)

Lunan, D.

2005-01-01

The outlook for natural gas in 2005 is said to be a watershed year, with a lengthy list of developments that could have significant effect on the industry for many years to come. In light of continuing high demand and static supply prospects, prices will have to continue to be high in order to ensure the necessary infrastructure investments to keep gas flowing from multiple sources to the consumer. It is predicted that against the backdrop of robust prices several supply initiatives will continue to advance rapidly in 2005, such as the $7 billion Mackenzie Gas Project on which public hearings are expected to start this summer, along with regulatory clarity about the $20 billion Alaska Highway Natural Gas Pipeline Project to move North Slope gas to southern markets. Drilling of new gas wells will continue to approach or even surpass 18,000 new wells, with an increasing number of these being coal-bed methane wells. Despite high level drilling activity, supply is expected to grow only about 400 MMcf per day. Greater supply increments are expected through continued LNG terminal development, although plans for new LNG terminal development have been met with stiff resistance from local residents both in Canada and the United States. Imports of liquefied natural gas into the United States slowed dramatically in 2004 under the severe short-term downward pressure on natural gas prices, nevertheless, these imports are expected to rebound to new record highs in 2005. Capacity is expected to climb from about 2.55 Bcf per day in 2004 to as much as 6.4 Bcf per day by late 2007. At least one Canadian import facility, Anadarko's one Bcf per day Bear Head terminal on Nova Scotia's Strait of Canso, is expected to become operational by late 2007 or early 2008. 6 photos

Outpatient versus inpatient mixed meal tolerance and arginine stimulation testing yields comparable measures of variability for assessment of beta cell function

Directory of Open Access Journals (Sweden)

Sudha S. Shankar

2018-06-01

Full Text Available Standard practice to minimize variability in beta cell function (BCF measurement is to test in inpatient (IP settings. IP testing strains trial subjects, investigators, and budgets. Outpatient (OP testing may be a solution although there are few reports on OP BCF testing variability. We compared variability metrics between OP and IP from a standardized mixed meal tolerance test (MMTT and arginine stimulation test (AST in two separate type 2 diabetes (T2DM cohorts (OP, n = 20; IP n = 22 in test-retest design. MMTT variables included: insulin sensitivity (Si; beta cell responsivity (Φtot; and disposition index (DItot = Si* Φtot following 470 kCal meal. AST variables included: acute insulin response to arginine (AIRarg and during hyperglycemia (AIRargMAX. Results: Baseline characteristics were well-matched. Between and within subject variance for each parameter across cohorts, and intraclass correlation coefficients (ICC-a measure of reproducibility across parameters were generally comparable for OP to IP. Table summarizes the ICC results for each key parameter and cohort.Test/ParameterOutpatient (95% CIInpatient (95% CIMMTT: Si0.49(0,0.690.28(0,0.60MMTT: Φtot0.65(0.16,0.890.81(0.44,0.93MMTT: DI0.67(0,0.830.36(0,0.69AST: AIR Arg0.96(0.88,0.980.84(0.59,0.94AST: AIR Arg Max0.97(0.90,0.990.95(0.86,0.97AST: ISR0.93(0.77,0.970.93(0.82,0.96In conclusion, the variability (reproducibility of BCF measures from standardized MMTT and AST is comparable between OP and IP settings. These observations have significant implications for complexity and cost of metabolic studies.

Alliance opens for business boosted by EIA forecast

International Nuclear Information System (INIS)

Jaremko, G.

2000-01-01

The Energy Information Administration (EIA) of the US Department of Energy recently released a new forecast showing US requirements for natural gas growing at a steady pace. By 2020, EIA says, pipeline imports will have climbed by 70 per cent to 5.8 Tcf per year. Tanker imports of natural gas liquids are also set to grow at the rate of 700 bcf annually by 2020. Much of the demand growth is expected to continue to be driven by the expanding use of natural gas in electricity generation, but there are across-the-board increases forecast in US residential, commercial and industrial gas consumption as well, thanks to a predicted overall economic growth of an average three per cent annually. If these predictions materialize, the initial excess pipeline capacity created by the Alliance Pipeline will shrink very quickly. Accordingly, the next major development spawned by Alliance, the Millenium Pipeline Project, an international effort which involves TransCanada Pipelines and Union Gas, as well as the Columbia Energy Group in the US, is expected to move ahead. A target of 2002 is set for the proposed 700 mmcf per day route across Lake Erie to New York State to New York City. In addition to Alliance, there is TransCanada Pipelines' 1.1 bcf per day new capacity added by the Foothills-Northern Border export route. Overall, an average of 1.0 bcf per day of excess capacity is predicted which will, however, last no more than two to five years. The EIA expects that new projects in Alaska and the Northwest Territories will soak up the excess capacity and set off a new round of expansion by the Canadian pipeline system

Concentration parameters for radionuclides by marine molluscs

Energy Technology Data Exchange (ETDEWEB)

Nakahara, Motokazu; Makamura, Ryoichi; Suzuki, Yuzuru; Matsuba, Mitsue [National Inst. of Radiological Sciences, Nakaminato, Ibaraki (Japan). Nakaminato Lab. Branch Office

1994-03-01

Accumulation of radionuclides from seawater and from food by marine molluscs was observed in the laboratory experiments to get bioconcentration parameters for the nuclides. The radionuclides investigated were {sup 57}Co, {sup 95m}Tc, {sup 103}Ru, {sup 137}Cs, {sup 65}Zn and {sup 54}Mn. Several species of molluscs containing pelecypods, gastropods and cephalopod were used for the experimental organisms. For the uptake experiment from seawater, the organisms were kept for more than seven days in radioactive seawater containing those radionuclides together. Then the organisms were transferred into nonradioactive seawater to observe the loss of the nuclides from the organisms. Biphasic loss curves were observed for all of the nuclides. Bioconcentration parameters, such as uptake rate, excretion rate, biological half-life and concentration factor at steady state were estimated from the uptake and excretion curves of the nuclides by the organisms by applying an exponential model. In the uptake experiments from radioactive food, the phytoplankton (Tetraselmis tetrathele), the brown algae (Eisenia bicyclis) and the viscera of abalone (Haliotis discus) were fed to bivalves, herbivorous gastropods and carnivorous molluscs, respectively. After single feeding of the labelled food with the nuclides, retention of the nuclides in whole body of the organisms was followed for several weeks or more. The organisms showed relatively high retention of the nuclides in whole body, except {sup 137}Cs and {sup 54}Mn. Retention of {sup 137}Cs and {sup 54}Mn in the organisms one day after feeding of radioactive food was lower than 25% of the radioactivity dosed. (author).

Phytoremediation of Heavy Metals in Contaminated Water and Soil Using Miscanthus sp. Goedae-Uksae 1.

Science.gov (United States)

Bang, Jihye; Kamala-Kannan, Seralathan; Lee, Kui-Jae; Cho, Min; Kim, Chang-Hwan; Kim, Young-Jin; Bae, Jong-Hyang; Kim, Kyong-Ho; Myung, Hyun; Oh, Byung-Taek

2015-01-01

The aim of this study is to characterize the heavy metal phytoremediation potential of Miscanthus sp. Goedae-Uksae 1, a hybrid, perennial, bio-energy crop developed in South Korea. Six different metals (As, Cu, Pb, Ni, Cd, and Zn) were used for the study. The hybrid grass effectively absorbed all the metals from contaminated soil. The maximum removal was observed for As (97.7%), and minimum removal was observed for Zn (42.9%). Similarly, Goedae-Uksae 1 absorbed all the metals from contaminated water except As. Cd, Pb, and Zn were completely (100%) removed from contaminated water samples. Generally, the concentration of metals in roots was several folds higher than in shoots. Initial concentration of metals highly influenced the phytoremediation rate. The results of the bioconcentration factor, translocation factor, and enrichment coefficient tests indicate that Goedae-Uksae 1 could be used for phytoremediation in a marginally contaminated ecosystem.

Growth and Heavy Metal Accumulation of Koelreuteria Paniculata Seedlings and Their Potential for Restoring Manganese Mine Wastelands in Hunan, China

Science.gov (United States)

Huang, Zhihong; Xiang, Wenhua; Ma, Yu’e; Lei, Pifeng; Tian, Dalun; Deng, Xiangwen; Yan, Wende; Fang, Xi

2015-01-01

The planting of trees on mine wastelands is an effective, long-term technique for phytoremediation of heavy metal-contaminated wastes. In this study, a pot experiment with seedlings of Koelreuteria paniculata under six treatments of local mine wastes was designed to determine the major constraints on tree establishment and to evaluate the feasibility of planting K. paniculata on manganese mine wastelands. Results showed that K. paniculata grew well in mine tailings, and also under a regime of equal amounts of mine tailings and soil provided in adjacent halves of pots. In contrast, mine sludge did not favor survival and growth because its clay texture limited fine root development. The bio-concentration factor and the translocation factor were mostly less than 1, indicating a low phytoextraction potential for K. paniculata. K. paniculata is suited to restore manganese mine sludge by mixing the mine sludge with local mine tailings or soil. PMID:25654773

Accumulation of Metals and Boron in Phragmites australis Planted in Constructed Wetlands Polishing Real Electroplating Wastewater.

Science.gov (United States)

Sochacki, Adam; Guy, Bernard; Faure, Olivier; Surmacz-Górska, Joanna

2015-01-01

The concentration of metals (Al, Cu, Fe, Mn, Ni, Zn) and B were determined in the above- and belowground biomass of Phragmites australis collected from the microcosm constructed wetland system used for the polishing of real electroplating wastewater. Translocation factor and bioconcentration factor were determined. Pearson correlation test was used to determine correlation between metal concentration in substrate and above- and belowground parts of Phragmites australis. The obtained results suggested that Phragmites australis did not play a major role as an accumulator of metals. It was observed also that the substrate could have exerted an effect on the translocation of Ni, Cu, Zn and Mn. The analysed concentrations of metals and B in biomass were in the range or even below the concentrations reported in the literature with the exception of Ni. The aboveground biomass was found suitable as a composting input in terms of metals concentrations.

Exact Open Quantum System Dynamics Using the Hierarchy of Pure States (HOPS).

Science.gov (United States)

Hartmann, Richard; Strunz, Walter T

2017-12-12

We show that the general and numerically exact Hierarchy of Pure States method (HOPS) is very well applicable to calculate the reduced dynamics of an open quantum system. In particular, we focus on environments with a sub-Ohmic spectral density (SD) resulting in an algebraic decay of the bath correlation function (BCF). The universal applicability of HOPS, reaching from weak to strong coupling for zero and nonzero temperature, is demonstrated by solving the spin-boson model for which we find perfect agreement with other methods, each one suitable for a special regime of parameters. The challenges arising in the strong coupling regime are not only reflected in the computational effort needed for the HOPS method to converge but also in the necessity for an importance sampling mechanism, accounted for by the nonlinear variant of HOPS. In order to include nonzero-temperature effects in the strong coupling regime we found that it is highly favorable for the HOPS method to use the zero-temperature BCF and include temperature via a stochastic Hermitian contribution to the system Hamiltonian.

Bioconcentration of elements by Poison pax (Paxillus involutus)

African Journals Online (AJOL)

Jerzy Falandysz

2012-03-08

Mar 8, 2012 ... brand new polyethylene bags and kept in dry and clean condition. Reagents. All reagents were of analytical reagent grade unless otherwise. Jarzyńska and Falandysz 4589 stated. Double distilled water (resistivity > 10 MΩ cm) was used for the preparation of solutions. The nitric acid (65% HNO3) was of.

Hemocytes are sites of persistence for virus-contaminated oysters

Science.gov (United States)

Like fecal bacteria, waterborne enteric viruses are readily bioconcentrated by bivalve shellfish. However while many bacteria decline rapidly when bivalves are placed in uncontaminated water, viruses tend to be retained within shellfish. In this study, we offer evidence that phagocytic blood cells...

An exploration of the relationship between adsorption and bioavailability of pesticides in soil to earthworm

Energy Technology Data Exchange (ETDEWEB)

Yu Yunlong [Department of Plant Protection, Zhejiang University, Kaixuan Road 268, Hangzhou, Zhejiang 310029 (China)]. E-mail: ylyu@zju.edu.cn; Wu Xiaomao [Department of Plant Protection, College of Agriculture, Guizhou University, Guiyang 550025 (China); Li Shaonan [Department of Plant Protection, Zhejiang University, Kaixuan Road 268, Hangzhou, Zhejiang 310029 (China); Fang Hua [Department of Plant Protection, Zhejiang University, Kaixuan Road 268, Hangzhou, Zhejiang 310029 (China); Zhan Haiyan [Department of Plant Protection, Zhejiang University, Kaixuan Road 268, Hangzhou, Zhejiang 310029 (China); Yu Jingquan [Department of Horticulture, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029 (China)

2006-06-15

A study was conducted to determine the adsorption/desorption of butachlor, myclobutanil and chlorpyrifos on five soils using a batch equilibration technique and to study the relationship between bioavailability to Allolobophora caliginosa and the adsorption/desorption of these three pesticides. The results showed that the adsorption/desorption processes of the tested compounds were mainly controlled by soil organic matter content (OM) and octanol/water-partitioning coefficient (K {sub ow}), and that the bioavailability of the pesticides was dependent on characteristics of pesticides, properties of soils, and uptake routes of earthworms. Bioconcentration of butachlor and myclobutanil was negatively correlated with Freundlich adsorption constant K {sub af} and K {sub df}. However, only a slightly positive correlation between bioconcentration and K {sub af} and K {sub df} was observed for chlorpyrifos due to its high affinity onto soil. - Bioavailability of pesticides in soil to earthworm is governed by adsorption characteristics.

Taiwan's industrial heavy metal pollution threatens terrestrial biota

International Nuclear Information System (INIS)

Hsu, M.J.; Selvaraj, K.; Agoramoorthy, G.

2006-01-01

The bioconcentration levels of essential (Cu, Fe, Mg, Mn, and Zn) and non-essential (As, Cd, Hg, Pb, and Sn) elements have been investigated in different terrestrial biota such as fungi, plant, earthworm, snail, crab, insect, amphibian, lizard, snake, and bat including the associated soil, to investigate the ecosystem health status in Kenting National Park, Taiwan. High bioconcentrations of Cd, Hg, and Sn in snail, earthworm, crab, lizard, snake, and bat indicated a contaminated terrestrial ecosystem. High concentrations of Cd, Hg, and Sn in plant species, effective bioaccumulation of Cd by earthworm, snail, crab and bat, as well as very high levels of Hg found in invertebrates, amphibians, and reptiles revealed a strong influence from industrial pollution on the biotic community. This study for the first time presents data on the impact of heavy metal pollution on various terrestrial organisms in Taiwan. - Metal effects occur at any terrestrial levels in Taiwan

Taiwan's industrial heavy metal pollution threatens terrestrial biota

Energy Technology Data Exchange (ETDEWEB)

Hsu, M.J. [Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung 804, Taiwan (China); Selvaraj, K. [Institute of Marine Geology and Chemistry, National Sun Yat-sen University, Kaohsiung 804, Taiwan (China); Agoramoorthy, G. [Department of Pharmacy, Tajen University, Yanpu, Pingtung 907, Taiwan (China)]. E-mail: agoram@mail.tajen.edu.tw

2006-09-15

The bioconcentration levels of essential (Cu, Fe, Mg, Mn, and Zn) and non-essential (As, Cd, Hg, Pb, and Sn) elements have been investigated in different terrestrial biota such as fungi, plant, earthworm, snail, crab, insect, amphibian, lizard, snake, and bat including the associated soil, to investigate the ecosystem health status in Kenting National Park, Taiwan. High bioconcentrations of Cd, Hg, and Sn in snail, earthworm, crab, lizard, snake, and bat indicated a contaminated terrestrial ecosystem. High concentrations of Cd, Hg, and Sn in plant species, effective bioaccumulation of Cd by earthworm, snail, crab and bat, as well as very high levels of Hg found in invertebrates, amphibians, and reptiles revealed a strong influence from industrial pollution on the biotic community. This study for the first time presents data on the impact of heavy metal pollution on various terrestrial organisms in Taiwan. - Metal effects occur at any terrestrial levels in Taiwan.

Use of a parallel artificial membrane system to evaluate passive absorption and elimination in small fish.

Science.gov (United States)

Kwon, Jung-Hwan; Katz, Lynn E; Liljestrand, Howard M

2006-12-01

A parallel artificial lipid membrane system was developed to mimic passive mass transfer of hydrophobic organic chemicals in fish. In this physical model system, a membrane filter-supported lipid bilayer separates two aqueous phases that represent the external and internal aqueous environments of fish. To predict bioconcentration kinetics in small fish with this system, literature absorption and elimination rates were analyzed with an allometric diffusion model to quantify the mass transfer resistances in the aqueous and lipid phases of fish. The effect of the aqueous phase mass transfer resistance was controlled by adjusting stirring intensity to mimic bioconcentration rates in small fish. Twenty-three simple aromatic hydrocarbons were chosen as model compounds for purposes of evaluation. For most of the selected chemicals, literature absorption/elimination rates fall into the range predicted from measured membrane permeabilities and elimination rates of the selected chemicals determined by the diffusion model system.

Studies on transfer, bioaccumulation and disappearance of glyphosate in the aquatic ecosystem by utilizing 14C tracer technique

International Nuclear Information System (INIS)

Zhu Guonian; Guo Jiangfeng; Sun Jinhe

2002-01-01

Studies on transfer, bioaccumulation and disappearance of glyphosate in the aquatic environment were conducted with methods of model tests and outdoor trials in the aquatic ecosystem. The result showed that glyphosate transferred rapidly into sediment and hormwort (Ceratopyllum demersum L.) after applied; and then, it was taken up faster and accumulated more by topmouth gudgeon (Psudorasobora parva) 5-10 days after application. The partitioning coefficient (sediment-water) and bioconcentration factors of glyphosate were 8.59, 27.96 and 45.79, respectively, in day 20. The concentration of glyphosate residue in the aquatic ecosystem followed the order of topmouth gudgeon > hormwort > sediment > water. And it was also indicated that glyphosate transferred and disappeared extremely fast in both pond and river after application

Characterisation of the potential hazards of water pollutants

Energy Technology Data Exchange (ETDEWEB)

Koch, R.

1986-01-01

The danger potential of chemicals to man and environment is essentially a function of exposure and toxicity. For the exposure of ecological systems there is decisive the distribution of the particular substance in and among the hydro-, pedo-, atmo- and biospheres. Proceeding from statistical relations between different molecular structure parameters and the distribution as well as action of substances, the approximate determination of distribution parameters, sorption coefficients and bioconcentration factors is possible. By means of a discriminant analysis the substances can be assigned to given classes of toxicity and mutagenicity. Proceeding from structure-analogy models, for several substances used as examples the distribution and toxicity parameters are calculated and an evaluation of the danger potential for aquatic ecosystems and man is discussed.

Estimation of the distribution coefficient by combined application of two different methods

International Nuclear Information System (INIS)

Vogl, G.; Gerstenbrand, F.

1982-01-01

A simple, non-invasive method is presented which permits determination of the rBCF and, in addition, of the distribution coefficient of the grey matter. The latter, which is closely correlated with the cerebral metabolism, has only been determined in vitro so far. The new method will be a means to check its accuracy. (orig.) [de

77 FR 7568 - Freeport LNG Expansion, L.P. and FLNG Liquefaction, LLC; Application for Long-Term Authorization...

Science.gov (United States)

2012-02-13

... that is sufficient to supply domestic demand for a century, even with significant exports of LNG. FLEX... is not prohibited by U.S. law or policy. The Application is filed independent of, and in addition to... application in Docket 10-161-LNG is 2.8 Bcf/d. FLEX further states that demand for liquefaction capacity has...

Studies on the possibilities of using a by-product resulting during the extraction of the volatile oils from conifer twigs and needles in the leather industry

Energy Technology Data Exchange (ETDEWEB)

Chirita, A.; Toma, A.R.; Cocis, V.

1979-01-01

Organic by-products containing 19-40% tannin from the water extraction of volatile oils from spruce bark, twigs, and needles were useful when mixed in a 1:1 ratio with BCF synthetic tannin auxiliary to tan hide, and similar by-products containing 16-31% reducing substances could be used to replace glucose as reducing agent in chrome tanning.

Teaching in the Land of Happiness: The Canada-Bhutan Connection

Science.gov (United States)

Scott, Kristen

2011-01-01

Classrooms in Bhutan overflow with eager students; however, the teacher supply is often not enough to meet demand. The Bhutan Canada Foundation (BCF) is a Canadian charity working with the Ministry of Education in Bhutan, providing Canadian teachers to remote areas, where they work for a local salary and live in basic conditions The feature of…

30 CFR 203.36 - Do I keep royalty relief if prices rise significantly?

Science.gov (United States)

2010-07-01

... 200 meters deep and entirely less than 400 meters deep. (3) $4.08 per MMBtu (i) The first 20 BCF of... less than 400 meters of water, the $4.55 per MMBtu price threshold applies to the whole RSV (see... that is located in water partly or entirely less than 200 meters deep issued before December 18, 2008...

Heavy metal biosorption by three bacteria isolated from a tropical river

African Journals Online (AJOL)

Bioaccumulation (bioconcentration) of four heavy metals cadmium, lead, zinc and nickel by three bacteria Bacillus, Staphylococcus and Pseudomonas as a tool for the decontamination of heavy metal impacted aquatic systems was investigated . The bacteria were obtained from the New Calabar River. Monitoring of the ...

Bioaccumulation of Aluminium in Hydromacrophytes in Polish Coastal Lakes

Directory of Open Access Journals (Sweden)

Senze Magdalena

2015-03-01

Full Text Available The research on aluminium content was conducted in water and on aquatic flora of Polish lakes in the central part of the coast. The study included the lakes Sarbsko, Choczewskie, Bia.e, K.odno, D.brze and Salino investigated in the summer of 2013. The examined lakes belong mainly to the direct basin of the Baltic Sea. Samples of aquatic plants and lake waters were collected. In the water samples pH and electrolytic conductivity were measured. The aluminium content was determined both in water and aquatic plants. Submerged hydromacrophyte studies included Myriophyllum alterniflorum L., Potamogeton perfoliatus L. and Ceratophyllum demersum L. Emergent hydromacrophyte studies included Phragmites australis (Cav. Trin. ex Steud., Juncus bulbosus L., Iris pseudacorus L., Eleocharis palustris (L. Roem. % Schult., Phalaris arundinacea L., Carex riparia Curt., Mentha aquatic L., Stratiotes aloides L., Alisma plantago-aquatica L., Glyceria maxima (Hartman Holmb., Sagittaria sagittifolia L., Scirpus lacustris L. and Typha angustifolia L. The purpose of this investigation was the determination of the aluminium content in submerged and emergent hydromacrophytes and also the definition of their bioaccumulative abilities. The average concentration of aluminium in water was 2.68 fęg Al dm.3. The average content of aluminium in plants was 2.8015 mg Al kg.1. The bioaccumulation factor ranged from BCF=19.74 to BCF=16619. On the basis of the analysis of the aluminium content in water and aquatic plants results show that both water and plants were characterized by a moderate level of aluminium. The recorded concentrations indicate a mid-range value and are much lower than those which are quoted for a variety of surface waters in various parts of the world.

The major and trace element chemistry of fish and lake water within ...

African Journals Online (AJOL)

Chemical elements in lake water are incorporated into fish tissues through bioconcentration and biomagnification. Lake water and fish tissue samples from 23 lakes, located within 4 major South African catchments, were analysed to investigate the link between element concentrations in lake water and otolith, fin spine, ...

Effects of Nigeria Ekete light crude oil on plasma electrolytes ...

African Journals Online (AJOL)

Hydrocarbon is known to alter blood parameters; some of these blood parameters may affect the activities of certain systems like cardiovascular system. Hydrocarbon gets into man and animal either through ingestion of contaminated food and water, bio-concentration through food chain, occupational exposure or by using ...

Accumulation of Heavy Metals in Tea Leaves and Potential Health Risk Assessment: A Case Study from Puan County, Guizhou Province, China

Science.gov (United States)

Yang, Ruidong; Chen, Rong; Peng, Yishu; Wen, Xuefeng; Gao, Lei

2018-01-01

This study features a survey of the concentrations of aluminum (Al) and heavy metals (Mn, Pb, Cd, Hg, As, Cr, Ni, Cu, and Zn) in tea leaves and the corresponding cultivation soils (0–30 cm), carried out in Puan County (Guizhou Province, China). The average concentrations of Al, Mn, Pb, Cd, Hg, As, Cr, Ni, Cu, and Zn in the soil were 106 × 103, 214, 20.9, 0.09, 0.12, 17.5, 121, 27.8, 131.2, and 64 mg·kg−1, respectively. The heavy metals’ pollution indexes in the soil can be ranked as follows: Cu > Cr > Hg > As > Ni > Zn > Pb > Mn > Cd. The soil was moderately polluted by Cu because of the high geochemical background value of Cu in the area. The potential environment risk index (RI) showed that 7.69% out of the total sample sites were within the moderate level. Moreover, the ranges of Al, Mn, Pb, Cd, Hg, As, Cr, Ni, Cu, and Zn concentrations in young tea leaves were 250–660, 194–1130, 0.107–0.400, 0.012–0.092, 0.014–0.085, 0.073–0.456, 0.33–1.26, 6.33–14.90, 14.90–26.10, and 35.8–50.3 mg·kg−1, respectively. While in mature tea leaves, they were 4300–10,400, 536–4610, 0.560–1.265, 0.040–0.087, 0.043–0.089, 0.189–0.453, 0.69–2.91, 3.43–14.20, 6.17–16.25, and 9.1–20.0 mg·kg−1, respectively. Furthermore, the concentrations of Pb, Cu, As, Hg, Cd, and Cr in young tea leaves and mature tea leaves were all lower than the standard limit values (5.0, 30, 2.0, 0.3, 1.0, and 5.0 mg·kg−1 for Pb, Cu, As, Hg, Cd, and Cr, respectively) in China. Besides, the accumulation ability of tea leaves to Mn was the strongest, and the average bioconcentration factor (BCF) of Mn in mature tea leaves was 12.5. In addition, the average target hazard quotients (THQ) were all less than one for the young tea leaves and the average aggregate risk hazard index (HI) to adults was 0.272, indicating that there was not a potential health risk for adults through the consumption of the infusions brewed by young tea leaves. However, for mature tea

Monitoring and assessment of mercury pollution in the vicinity of a chloralkali plant. III. Concentration and genotoxicity of mercury in the industrial effluent and contaminated water of Rushikulya estuary, India.

Science.gov (United States)

Panda, K K; Lenka, M; Panda, B B

1992-01-01

Aquatic mercury pollution of the Rushikulya estuary in the vicinity of the chloralkali plant at Ganjam, India was monitored over a period from October 1987 to May 1989. The concentrations of aquatic mercury in the water samples taken from the effluent channel and from different sites along the course of the estuary covering a distance of 2 km were periodically recorded and ranged from 0 to 0.5 mg/l. The bioconcentration and genotoxicity of aquatic mercury in the samples were assessed by the Allium micronucleus (MNC) assay. The frequency of cells with MNC was highly correlated not only with bioconcentrated mercury (root mercury) but also with the levels of aquatic mercury. The threshold assessment values such as effective concentration fifty (EC50) for root growth, lowest effective concentration tested (LECT), and highest ineffective concentration tested (HICT) for induction of MNC in Allium MNC assay for the present aquatic industrial mercury were determined to be 0.14, 0.06 and 0.02 mg/l, respectively.

Immobilisation of Cu, Pb and Zn in Scrap Metal Yard Soil Using Selected Waste Materials.

Science.gov (United States)

Kamari, A; Putra, W P; Yusoff, S N M; Ishak, C F; Hashim, N; Mohamed, A; Isa, I M; Bakar, S A

2015-12-01

Immobilisation of heavy metals in a 30-year old active scrap metal yard soil using three waste materials, namely coconut tree sawdust (CTS), sugarcane bagasse (SB) and eggshell (ES) was investigated. The contaminated soil was amended with amendments at application rates of 0 %, 1 % and 3 % (w/w). The effects of amendments on metal accumulation in water spinach (Ipomoea aquatica) and soil metal bioavailability were studied in a pot experiment. All amendments increased biomass yield and reduced metal accumulation in the plant shoots. The bioconcentration factor and translocation factor values of the metals were in the order of Zn > Cu > Pb. The addition of ES, an alternative source of calcium carbonate (CaCO3), has significantly increased soil pH and resulted in marked reduction in soil metal bioavailability. Therefore, CTS, SB and ES are promising low-cost immobilising agents to restore metal contaminated land.

Phytoextraction potential of poplar (Populus alba L. var. pyramidalis Bunge) from calcareous agricultural soils contaminated by cadmium.

Science.gov (United States)

Hu, Yahu; Nan, Zhongren; Jin, Cheng; Wang, Ning; Luo, Huanzhang

2014-01-01

To investigate the phytoextraction potential of Populus alba L. var. pyramidalis Bunge for cadmium (Cd) contaminated calcareous soils, a concentration gradient experiment and a field sampling experiment (involving poplars of different ages) were conducted. The translocation factors for all experiments and treatments were greater than 1. The bioconcentration factor decreased from 2.37 to 0.25 with increasing soil Cd concentration in the concentration gradient experiment and generally decreased with stand age under field conditions. The Cd concentrations in P. pyramidalis organs decreased in the order of leaves > stems > roots. The shoot biomass production in the concentration gradient experiment was not significantly reduced with soil Cd concentrations up to or slightly over 50 mg kg(-1). The results show that the phytoextraction efficiency of P. pyramidalis depends on both the soil Cd concentration and the tree age. Populus pyramidalis is most suitable for remediation of slightly Cd contaminated calcareous soils through the combined harvest of stems and leaves under actual field conditions.

Changes in bioaccumulation and translocation patterns between root and leafs of Avicennia schaueriana as adaptive response to different levels of metals in mangrove system.

Science.gov (United States)

Souza, Iara da C; Rocha, Lívia D; Morozesk, Mariana; Bonomo, Marina M; Arrivabene, Hiulana P; Duarte, Ian D; Furlan, Larissa M; Monferrán, Magdalena V; Mazik, Krysia; Elliott, Michael; Matsumoto, Silvia T; Milanez, Camilla R D; Wunderlin, Daniel A; Fernandes, Marisa N

2015-05-15

Espírito Santo estuaries (Brazil) are impacted by industrial activities, resulting in contamination of water and sediments. This raise questions on biological uptake, storage and consequences of metal contamination to mangrove plants. The goal of this work was evaluating accumulation and translocation of metals from sediment to roots and leaves of Avicennia schaueriana, growing in areas with different degrees of contamination, correlating bioaccumulation with changes in its root anatomy. Highest bioconcentration factors (BCFs) were observed in plants growing in less polluted areas. Conversely, highest translocation factors were found in plants from highest polluted area, evidencing an adaptive response of A. schaueriana to less favourable conditions. Namely, the absorption of metals by roots is diminished when facing highest levels of metals in the environment; alternatively, plants seem to enhance the translocation to diminish the concentration of toxic metals in roots. Root also responded to highly polluted scenarios with modifications of its anatomy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Growth and Heavy Metal Accumulation of Koelreuteria Paniculata Seedlings and Their Potential for Restoring Manganese Mine Wastelands in Hunan, China

Directory of Open Access Journals (Sweden)

Zhihong Huang

2015-02-01

Full Text Available The planting of trees on mine wastelands is an effective, long-term technique for phytoremediation of heavy metal-contaminated wastes. In this study, a pot experiment with seedlings of Koelreuteria paniculata under six treatments of local mine wastes was designed to determine the major constraints on tree establishment and to evaluate the feasibility of planting K. paniculata on manganese mine wastelands. Results showed that K. paniculata grew well in mine tailings, and also under a regime of equal amounts of mine tailings and soil provided in adjacent halves of pots. In contrast, mine sludge did not favor survival and growth because its clay texture limited fine root development. The bio-concentration factor and the translocation factor were mostly less than 1, indicating a low phytoextraction potential for K. paniculata. K. paniculata is suited to restore manganese mine sludge by mixing the mine sludge with local mine tailings or soil.

Performance of bioaugmentation-assisted phytoextraction applied to metal contaminated soils: A review

Energy Technology Data Exchange (ETDEWEB)

Lebeau, Thierry [Equipe Depollution Biologique des Sols (EDBS), University of Haute-Alsace, 28, rue de Herrlisheim, BP 50 568, 68 008 Colmar Cedex (France)], E-mail: thierry.lebeau@uha.fr; Braud, Armelle; Jezequel, Karine [Equipe Depollution Biologique des Sols (EDBS), University of Haute-Alsace, 28, rue de Herrlisheim, BP 50 568, 68 008 Colmar Cedex (France)

2008-06-15

Bioaugmentation-assisted phytoextraction is a promising method for the cleaning-up of soils contaminated by metals. Bacteria mainly Plant Growth Promoting Rhizobacteria (PGPR) and fungi mainly Arbuscular Mycorrhizal Fungi (AMF) associated with hyperaccumulating or non-hyperaccumulating plants were analyzed on the basis of a bioprocess engineering approach (concentration and amount of metals extracted by plants, translocation and bioconcentration factor, and plant biomass). In average bioaugmentation increased metals accumulated by shoots by a factor of about 2 (metal concentration) and 5 (amount) without any obvious differences between bacteria and fungi. To optimize this process, new relevant microorganism-plant associations and field scale experiments are needed along with a common methodology for the comparison of all experiments on the same basis. Recommendations were suggested concerning both the microbial-plant selection and the implementation of bioaugmentation to enhance the microbial survival. The use of microbial consortia associated with plant was discussed notably for multi-contaminated soils. - Bioaugmentation-assisted plant improves the phytoextraction performances for soils contaminated by metals.

Phytoextraction and phytostabilization potential of plants grown in the vicinity of heavy metal-contaminated soils: a case study at an industrial town site.

Science.gov (United States)

Lorestani, B; Yousefi, N; Cheraghi, M; Farmany, A

2013-12-01

With the development of urbanization and industrialization, soils have become increasingly polluted by heavy metals. Phytoremediation, an emerging cost-effective, nonintrusive, and aesthetically pleasing technology that uses the remarkable ability of plants to concentrate elements, can be potentially used to remediate metal-contaminated sites. In this research, two processes of phytoremediation (phytoextraction and phytostabilization) were surveyed in some plant species around an industrial town in the Hamedan Province in the central-western part of Iran. To this purpose, shoots and roots of the seven plant species and the associated soil samples were collected and analyzed by measuring Pb, Fe, Mn, Cu, and Zn concentrations using ICP-AES and then calculating the biological absorption coefficient, bioconcentration factor, and translocation factor parameters for each element. The obtained results showed that among the collected plants, Salsola soda is the most effective species for phytoextraction and phytostabilization and Cirsium arvense has the potential for phytostabilization of the measured heavy metals.

Performance of bioaugmentation-assisted phytoextraction applied to metal contaminated soils: A review

International Nuclear Information System (INIS)

Lebeau, Thierry; Braud, Armelle; Jezequel, Karine

2008-01-01

Bioaugmentation-assisted phytoextraction is a promising method for the cleaning-up of soils contaminated by metals. Bacteria mainly Plant Growth Promoting Rhizobacteria (PGPR) and fungi mainly Arbuscular Mycorrhizal Fungi (AMF) associated with hyperaccumulating or non-hyperaccumulating plants were analyzed on the basis of a bioprocess engineering approach (concentration and amount of metals extracted by plants, translocation and bioconcentration factor, and plant biomass). In average bioaugmentation increased metals accumulated by shoots by a factor of about 2 (metal concentration) and 5 (amount) without any obvious differences between bacteria and fungi. To optimize this process, new relevant microorganism-plant associations and field scale experiments are needed along with a common methodology for the comparison of all experiments on the same basis. Recommendations were suggested concerning both the microbial-plant selection and the implementation of bioaugmentation to enhance the microbial survival. The use of microbial consortia associated with plant was discussed notably for multi-contaminated soils. - Bioaugmentation-assisted plant improves the phytoextraction performances for soils contaminated by metals

A newly found cadmium accumulator-Malva sinensis Cavan

International Nuclear Information System (INIS)

Zhang Shirong; Chen Mingying; Li Ting; Xu Xiaoxun; Deng Liangji

2010-01-01

Screening hyperaccumulators and accumulators is a key step in the phytoremediation of soils contaminated by heavy metals. A pot experiment was conducted involving a soil Cd concentration gradient (0, 50, 75, 100, 125, 150, 175, and 200 mg kg -1 ) to determine if Malva sinensis Cavan. from two lead-zinc mines in Kangding and Yajiang in western Sichuan, China, is a Cd-hyperaccumulator. The highest Cd concentrations in plant shoots from Kangding and Yajiang were 154.30 and 122.77 mg kg -1 , respectively, at a soil Cd concentration of 200 mg kg -1 . The largest amounts of accumulation in plant shoots from Kangding and Yajiang were 700.5 and 1403.2 μg pot -1 , respectively. The bioconcentration factors in shoots were 0.53-1.03 for Kangding and 0.69-1.25 for Yajiang. Moreover, all translocation factors of plants from the two sites were over 1.0. Therefore, M. sinensis can be classified as a Cd-accumulator or non-standard Cd-hyperaccumulator.

Medición de las capacidades físicas de adultos mayores de Quebec: un análisis secundario del estudio NuAge Measurement of physical capacities in the elderly: a secondary analysis of the Quebec longitudinal study NuAge

Directory of Open Access Journals (Sweden)

José Alberto Ávila-Funes

2006-12-01

Full Text Available OBJETIVO: Determinar la validez de una batería de pruebas de capacidades físicas en una muestra de adultos mayores de la comunidad. MATERIAL Y MÉTODOS: Para este estudio se analizaron los datos basales del estudio NuAge, recolectados de diciembre de 2003 a abril de 2005 y que incluyeron 1 793 varones (48% y mujeres (52% (74.4 ± 4.1 años de Montreal, Laval y Sherbrooke, Canadá. Se construyó una batería para la medición de las capacidades físicas (BCF a partir de la suma de cuatro pruebas según el método propuesto por Guralnik (equilibrio en un pie, velocidad de la marcha en cuatro metros a paso normal, levantarse de una silla cinco veces y el timed "up & go". Mediante análisis de regresión lineal se establecieron la asociación de la edad, el sexo y la actividad física con la BCF. RESULTADOS: La BCF se asoció de forma significativa con pruebas que evalúan el estado físico y de salud de los individuos, por lo que se determinó la validez de contenido y de criterio. La BCF tuvo un coeficiente alfa de 0.74. Los análisis de regresión probaron que la disminución en las capacidades físicas relacionadas con la edad es similar en varones y mujeres. CONCLUSIÓN: La batería es una herramienta válida en la medición de las capacidades físicas. El mejor desempeño ocurre en los individuos más jóvenes, aquéllos con más actividad física y en los varones. Esta BCF puede servir de modelo para utilizarse en el estudio de las capacidades de los adultos mayores que viven en la comunidad.OBJECTIVE: To assess the validity of a battery of functional capacity tests in community-living elderly Canadians. MATERIAL AND METHODS: Design: cross-sectional study. Study population: baseline data from 1793 men and women aged 74.4 ± 4.1 participating in the NuAge longitudinal study were collected from December 2003 to April 2005 and used for the analyses. A global score measuring functional capacities (BFC was constructed as the sum of four tests

Cyber Power for the Joint Force Commander: An Operational Design Framework

Science.gov (United States)

2014-03-26

b088-f3d477b4329c/en/ INSS +Memorandum_MAY2012_Nr117.pdf (accessed November 5, 2013). Cyberspace is described as three (human, logical, and physical...2012. http://mercury.ethz.ch/serviceengine/Files/ISN/152953/ipublicationdocument_singledocument/f3 e19de1-bcf7-4d07-b088-f3d477b4329c/en/ INSS

Trace metal geochemistry in mangrove sediments and their transfer to mangrove plants (New Caledonia)

International Nuclear Information System (INIS)

Marchand, C.; Fernandez, J.-M.; Moreton, B.

2016-01-01

Because of their physico-chemical inherent properties, mangrove sediments may act as a sink for pollutants coming from catchments. The main objective of this study was to assess the distribution of some trace metals in the tissues of various mangrove plants developing downstream highly weathered ferralsols, taking into account metals partitioning in the sediment. In New Caledonia, mangroves act as a buffer between open-cast mines and the world's largest lagoon. As a result of the erosion of lateritic soils, Ni and Fe concentrations in the sediment were substantially higher than the world average. Whatever the mangrove stand and despite low bioaccumulation and translocations factors, Fe and Ni were also the most abundant metals in the different plant tissues. This low bioaccumulation may be explained by: i) the low availability of metals, which were mainly present in the form of oxides or sulfur minerals, and ii) the root systems acting as barriers towards the transfer of metals to the plant. Conversely, Cu and Zn metals had a greater mobility in the plant, and were characterized by high bioconcentration and translocation factors compared to the other metals. Cu and Zn were also more mobile in the sediment as a result of their association with organic matter. Whatever the metal, a strong decrease of trace metal stock was observed from the landside to the seaside of the mangrove, probably as a result of the increased reactivity of the sediment due to OM enrichment. This reactivity lead to higher dissolution of bearing phases, and thus to the export of dissolved trace metals trough the tidal action. Cu and Zn were the less concerned by the phenomenon probably as a result of higher plant uptake and their restitution to the sediment with litter fall in stands where tidal flushing is limited. - Highlights: • Unusual high concentrations of Fe and Ni were measured in mangrove tissues. • Bioconcentration and translocation factors of Fe, Ni, Co and Mn were low. • Low

Trace metal geochemistry in mangrove sediments and their transfer to mangrove plants (New Caledonia)

Energy Technology Data Exchange (ETDEWEB)

Marchand, C., E-mail: cyril.marchand@ird.fr [Institut de Recherche pour le Développement (IRD), UR 206/UMR 7590 IMPMC, 98848 Nouméa, New Caledonia (France); Fernandez, J.-M.; Moreton, B. [AEL/LEA, 7 rue Loriot de Rouvray, 98800 Nouméa, New Caledonia (France)

2016-08-15

Because of their physico-chemical inherent properties, mangrove sediments may act as a sink for pollutants coming from catchments. The main objective of this study was to assess the distribution of some trace metals in the tissues of various mangrove plants developing downstream highly weathered ferralsols, taking into account metals partitioning in the sediment. In New Caledonia, mangroves act as a buffer between open-cast mines and the world's largest lagoon. As a result of the erosion of lateritic soils, Ni and Fe concentrations in the sediment were substantially higher than the world average. Whatever the mangrove stand and despite low bioaccumulation and translocations factors, Fe and Ni were also the most abundant metals in the different plant tissues. This low bioaccumulation may be explained by: i) the low availability of metals, which were mainly present in the form of oxides or sulfur minerals, and ii) the root systems acting as barriers towards the transfer of metals to the plant. Conversely, Cu and Zn metals had a greater mobility in the plant, and were characterized by high bioconcentration and translocation factors compared to the other metals. Cu and Zn were also more mobile in the sediment as a result of their association with organic matter. Whatever the metal, a strong decrease of trace metal stock was observed from the landside to the seaside of the mangrove, probably as a result of the increased reactivity of the sediment due to OM enrichment. This reactivity lead to higher dissolution of bearing phases, and thus to the export of dissolved trace metals trough the tidal action. Cu and Zn were the less concerned by the phenomenon probably as a result of higher plant uptake and their restitution to the sediment with litter fall in stands where tidal flushing is limited. - Highlights: • Unusual high concentrations of Fe and Ni were measured in mangrove tissues. • Bioconcentration and translocation factors of Fe, Ni, Co and Mn were low. �

Sub-chronic exposure to fluoxetine in juvenile oysters (Crassostrea gigas): uptake and biological effects.

Science.gov (United States)

Di Poi, Carole; Evariste, Lauris; Séguin, Alexis; Mottier, Antoine; Pedelucq, Julie; Lebel, Jean-Marc; Serpentini, Antoine; Budzinski, Hélène; Costil, Katherine

2016-03-01

The bioconcentration potential of fluoxetine (FLX) and its biological effects were investigated in juvenile Pacific oyster exposed for 28 days to environmentally relevant concentrations of FLX (1 ng L(-1), 100 ng L(-1) and up to 10 μg L(-1)). FLX bioaccumulated in oyster flesh resulting in 28-day bioconcentration factors greater than 2,000 and 10,000 by referring to wet and dry weights, respectively. Nevertheless, FLX did not induce oyster mortality, delayed gametogenesis, or lead to adverse histopathological alterations. At the two highest concentrations, despite non-optimal trophic conditions, FLX stimulated shell growth but only in a transient manner, suggesting a role of serotonin in the regulation of feeding and metabolism in bivalves. Those high concentrations seemed to drive bell-shaped responses of catalase and glutathione S-transferase activities throughout the exposure period, which may indicate the activation of antioxidant enzyme synthesis and then an enhanced catabolic rate or direct inhibition of those enzymes. However, no clear oxidative stress was detected because no strong differences in thiobarbituric acid-reactive substance (TBARS) content (i.e. lipid peroxidation) were observed between oyster groups, suggesting that cellular defence mechanisms were effective. These results demonstrate the importance of considering additional biomarkers of oxidative stress to obtain a comprehensive overview of the FLX-induced changes in marine bivalves exposed under realistic conditions. Considering the battery of biomarkers used, FLX appears to induce little or no effects on oyster physiology even at a concentration of 10 μg L(-1). These results do not confirm the lowest observed effect concentration (LOEC) values reported by some authors in other mollusc species.

Monitoring device for the reactor power distribution

International Nuclear Information System (INIS)

Uematsu, Hitoshi; Tsuiki, Makoto

1982-01-01

Purpose: To enable accurate monitoring for the power distribution in a short time, as well as independent detection for in-core neutron flux detectors in abnormal operation due to failures or like other causes to thereby surely provide reliable substitute values. Constitution: Counted values are inputted from a reactor core present status data detector by a power distribution calculation device to calculate the in-core neutron flux density and the power distribution based on previously stored physical models. While on the other hand, counted value from the in-core neutron detectors and the neutron flux distribution and the power distribution calculated from the power distribution calculation device are inputted from a BCF calculation device to compensate the counting errors incorporated in the counted value from the in-core neutron flux detectors and the calculation errors incorporated in the power distribution calculated in the power distribution calculation device respectively and thereby calculate the power distribution in the reactor core. Further, necessary data are inputted to the power distribution calculation device by an input/output device and the results calculated in the BCF calculation device are displayed. (Aizawa, K.)

The impact of northern gas on North American gas infrastructure

International Nuclear Information System (INIS)

Letwin, S.

2004-01-01

The three business units that Enbridge operates are crude oil pipelines; natural gas liquids (NGL) transportation; and gas transmission and distribution. The need for more infrastructure will increase as the demand for natural gas increases. This presentation outlined the issues that surround and sometimes impede infrastructure development. It also emphasized the need for northern gas supply at a time when conventional natural gas supplies are decreasing and demand is growing. Additional LNG supply is required along with new supply from Alaska, Mackenzie Delta and the east coast. The issue of a secure source of supply was discussed along with northern gas expectations. It is expected that Mackenzie Delta gas (1.2 bcf/day) will be available by 2008 to 2010 and Alaska North Slope gas (4 bcf/day) will be available from 2012 to 2014. Gas demand by industrial, residential, commercial and power generation sectors across North America was illustrated. The challenge lies in creating infrastructure to move the supply to where it is most in demand. General infrastructure issues were reviewed, such as prices, regulatory streamlining, lead times, stakeholder issues and supporting infrastructure. 19 figs

Bioavailability of energy-effluent materials in coastal ecosystems

International Nuclear Information System (INIS)

Hardy, J.T.

1987-01-01

An attempt is made to study the long-term effects of effluents from coastal and offshore nuclear power plants. The original intent of the program was to integrate approaches in chemistry, ocean transport, and biological uptake to quantify the variables that regulate biological availability of energy-effluent materials. Initial work was focused on the fate and effects of copper. In later research, the authors examined the basic environmental variables controlling the bioavailability of energy-related contaminants. They investigated how factors such as dissolved organic compounds, suspended particles, and sediment binding affected chemical speciation and how chemical speciation, in turn, influenced the availability of metals and radionuclides to marine invertebrates. They developed a hydrodynamic model to predict sediment and contaminant transport, and they quantified the bioconcentration of synthetic-fuel residuals in plankton

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

There are evidences to show that response to ionizing radiations have genetic influence. To investigate this further, reciprocal F1 hybrids were genereted by crossbreeding the radiation-susceptible BALB/c mouse strain with resistant C57BL/6 in a sex-specific manner (BALB/c♂×C57BL/6♀ = B6BcF1; C57BL/6♂× BALB/c♀ ...

Fuel pin behavior under slow ramp-type transient-overpower conditions in the CABRI-FAST experiments

International Nuclear Information System (INIS)

Fukano, Yoshitaka; Onoda, Yuichi; Sato, Ikken; Charpenel, Jean

2009-01-01

In the CABRI-FAST experimental program, four in-pile tests were performed with slow power-ramp-type transient-overpower conditions (called hereafter as 'slow TOP') to study transient fuel pin behavior under inadvertent control rod withdrawal events in liquid metal cooled fast breeder reactors. Annular-pellet fuel pins were used in three tests, while a solid-pellet fuel pin was used in the other test. All of these pins were pre-irradiated in Phenix. The slow TOP test with a solid-pellet fuel pin was realized as a comparatory test against an existing test (E12) in the CABRI-2 program. In the CABRI-FAST test (BCF1), a power ramp rate of 3% Po/s was applied, while in the CABRI-2 test, 1% Po/s was adopted. Moreover, overpower condition was maintained for a few seconds beyond the observed pin failure in the BCF1 test. In spite of the different power ramp rates, evaluated fuel thermal conditions at the observed failure time are quite similar. The continued overpower condition in the BCF1 test resulted in gradual degradation of the pin structure providing information effective for evaluation of various accident scenarios. Three slow TOP tests with the annular fuel in the CABRI-FAST program resulted in no pin failure showing high failure threshold. Based on post-test examination data and a theoretical evaluation, it was concluded that intra-pin free spaces, such as central hole, macroscopic cracks and fuel-cladding gap effectively mitigated fuel cladding mechanical interaction. It was also clarified that cavity pressurization became effective only in case of very large amount of fuel melting. Furthermore, such cavity pressurization was effectively mitigated by a molten-fuel squirting into the upper blanket region pushing the blanket pellets upward. These CABRI FAST slow TOP tests, in combination with the existing CABRI and TREAT tests, provided an extended slow TOP test database with various fuel and transient conditions. (author)

TH-CD-201-03: A Real-Time Method to Simultaneously Measure Linear Energy Transfer and Dose for Proton Therapy Using Organic Scintillators

Energy Technology Data Exchange (ETDEWEB)

Alsanea, F; Therriault-Proulx, F; Sawakuchi, G; Beddar, S [UT MD Anderson Cancer Center, Houston, TX (United States)

2016-06-15

Purpose: The light generated in organic scintillators depends on both the radiation dose and the linear energy transfer (LET). The LET dependence leads to an under-response of the detector in the Bragg peak of proton beams. This phenomenon, called ionization quenching, must be corrected to obtain accurate dose measurements of proton beams. This work exploits the ionization quenching phenomenon to provide a method of measuring LET and auto correcting quenching. Methods: We exposed simultaneously four different organic scintillators (BCF-12, PMMA, PVT, and LSD; 1mm in diameter) and a plane parallel ionization chamber in passively scattered proton beams to doses between 32 and 43 cGy and fluence averaged LET values from 0.47 to 1.26 keV/µm. The LET values for each irradiation condition were determined using a validated Monte Carlo model of the beam line. We determined the quenching parameter in the Birk’s equation for scintillation in BCF-12 for dose measurements. One set of irradiation conditions was used to correlate the scintillation response ratio to the LET values and plot a scintillation response ratio versus LET calibration curve. Irradiation conditions independent from the calibration ones were used to validate this method. Comparisons to the expected values were made on both the basis of dose and LET. Results: Among all the scintillators investigated, the ratio of PMMA to BCF-12 provided the best correlation to LET values and was used as the LET calibration curve. The expected LET values in the validation set were within 2%±6%, which resulted in dose accuracy of 1.5%±5.8% for the range of LET values investigated in this work. Conclusion: We have demonstrated the feasibility of using the ratio between the light output of two organic scintillators to simultaneously measure LET and dose of therapeutic proton beams. Further studies are needed to verify the response in higher LET values.

Tembaga (Cu Menurunkan Kandungan Pigmen dan Pertumbuhan Mikroalga Merah, Porphyridium cruentum (Effect of Copper on Pigments Content and Growth of Red Microalgae, Porphyridium cruentum

Directory of Open Access Journals (Sweden)

Reza Hafiz Pranajaya

2014-06-01

cruentum.This study aims to find out the influence of copper exposure levels on chlorophyll, pigment Phycobiliproteins, and the growth of microalgae Porphyridium cruentum. P. cruentum stock was collected from Main Center Brackish Water Aquaculture Development, Situbondo. The research design this study used a experimental laboratory. Concentrations of heavy metals Cu used are 0 ppm as control, 1 ppm, 2 ppm, 3 ppm, and 4 ppm. Heavy metals Cu analysised by AAS and measurent pigments (chlorophyll and phycobiliproteins performed by spectrometric UV-Vis. The results showed that heavy metals Cu with different concentrations give a very effect influence (P<0.01 to pigment (chlorophyll and phycobiliproteins content, BCF, and effect influence (P<0.05 to growth. The high Cu resulted decrease to growth of microalgae, cell density, pigments (chlorophyll and phycobiliproteins, and bio concentration factor Porphyridium cruentum. The highly percentage absorption of heavy metals Cu at 13.1% (1 ppm, 8.2% (2 ppm, 6.9% (3 ppm, and 2.6% (4 ppm. The results suggest that P. cruentum has the potential as bioremediator. Keywords: Porphyridium cruentum; chlorophyll; phycobiliproteins; growth; copper

Allometric relationships in the bioconcentration of heavy metals by the edible tropical clam Gafrarium tumidum

International Nuclear Information System (INIS)

Hedouin, L.; Metian, M.; Teyssie, J.-L.; Fowler, S.W.; Fichez, R.; Warnau, M.

2006-01-01

Although metal contamination is a problem of major concern in the lagoon of New Caledonia due to intense mining activities conducted on land, very little is known on the metal ecotoxicology of local marine organisms. The clam Gafrarium tumidum was investigated to assess its usefulness as a bioindicator species of metal contamination in this lagoon. More particularly, allometric relationships between metal accumulation and clam size were determined for five common metals in New Caledonian lagoon waters (Cd, Cr, Co, Zn and Ag) using a highly sensitive radiotracer technique. Experimental results showed that allometric relationships were dependent on the element and on the body compartment considered. As a rule, allometric relationships of metal concentration factor were more pronounced in shell than in soft parts. Significant relationships with clam size for Cd, Cr, Co and Zn followed inverse power functions. In contrast, the degree of Ag bioaccumulation was positively correlated with size. In view of the literature on Ag in bivalves, the latter observation suggests the occurrence of a specific detoxification mechanism (sequestration) that would be more efficient in old individuals. Overall, the experimental results indicate that the use of G. tumidum as a bioindicator in monitoring programmes requires selecting individuals of a specific size range in order to obtain comparable information about ambient metal levels. Since the size effect is greatest among smaller individuals, it is recommended to select clams with a shell width greater than 35 mm

Allometric relationships in the bioconcentration of heavy metals by the edible tropical clam Gafrarium tumidum

Energy Technology Data Exchange (ETDEWEB)

Hedouin, L. [International Atomic Energy Agency-Marine Environment Laboratory, 4 Quai Antoine 1er, MC-98000 Monaco (Monaco); Laboratoire de Biologie et d' Environnement Marins, FRE 2727, La Rochelle University, 22 Av. Michel Crepeau, F-17000 La Rochelle (France); Institut de Recherche pour le Developpement, Centre d' Oceanologie de Marseille, Station Marine d' Endoume, Rue de la Batterie des Lions, F-13007 Marseille (France); Metian, M. [International Atomic Energy Agency-Marine Environment Laboratory, 4 Quai Antoine 1er, MC-98000 Monaco (Monaco); Teyssie, J.-L. [International Atomic Energy Agency-Marine Environment Laboratory, 4 Quai Antoine 1er, MC-98000 Monaco (Monaco); Fowler, S.W. [International Atomic Energy Agency-Marine Environment Laboratory, 4 Quai Antoine 1er, MC-98000 Monaco (Monaco); Fichez, R. [Institut de Recherche pour le Developpement, Centre d' Oceanologie de Marseille, Station Marine d' Endoume, Rue de la Batterie des Lions, F-13007 Marseille (France); Warnau, M. [International Atomic Energy Agency-Marine Environment Laboratory, 4 Quai Antoine 1er, MC-98000 Monaco (Monaco)]. E-mail: m.warnau@iaea.org

2006-07-31

Although metal contamination is a problem of major concern in the lagoon of New Caledonia due to intense mining activities conducted on land, very little is known on the metal ecotoxicology of local marine organisms. The clam Gafrarium tumidum was investigated to assess its usefulness as a bioindicator species of metal contamination in this lagoon. More particularly, allometric relationships between metal accumulation and clam size were determined for five common metals in New Caledonian lagoon waters (Cd, Cr, Co, Zn and Ag) using a highly sensitive radiotracer technique. Experimental results showed that allometric relationships were dependent on the element and on the body compartment considered. As a rule, allometric relationships of metal concentration factor were more pronounced in shell than in soft parts. Significant relationships with clam size for Cd, Cr, Co and Zn followed inverse power functions. In contrast, the degree of Ag bioaccumulation was positively correlated with size. In view of the literature on Ag in bivalves, the latter observation suggests the occurrence of a specific detoxification mechanism (sequestration) that would be more efficient in old individuals. Overall, the experimental results indicate that the use of G. tumidum as a bioindicator in monitoring programmes requires selecting individuals of a specific size range in order to obtain comparable information about ambient metal levels. Since the size effect is greatest among smaller individuals, it is recommended to select clams with a shell width greater than 35 mm.

Levels and bioaccumulation of organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) in fishes from the Pearl River estuary and Daya Bay, South China

International Nuclear Information System (INIS)

Guo Lingli; Qiu Yaowen; Zhang Gan; Zheng, Gene J.; Lam, Paul K.S.; Li Xiangdong

2008-01-01

Fifty fish samples were collected from the Pearl River estuary (PRE) and Daya Bay, South China and were analyzed for DDTs, HCHs, chlordanes and polybrominated biphenyl ethers (PBDEs). Except the high concentrations of DDT observed in fishes, the concentrations of HCHs, chlordanes and PBDEs were low when compared to other regions. BDE-47 was the predominant PBDE congener and the BDE-209 concentrations were relatively low, despite its high concentration in surface sediments. The absence of significant increase of DDT, HCH, chlordane and PBDE concentrations towards higher δ 15 N values, as well as the lack of a significant correlation (p 15 N, may indicate a weak biomagnification of these chemicals in the food webs. Good agreement was observed between their concentrations and lipid contents of the organisms. Bioconcentration was suggested to be responsible for the accumulation of OCPs and PBDEs in the lower trophic organisms in the studied subtropical waters. - Bioconcentration was suggested to be responsible for the accumulation of OCPs and PBDEs in the lower trophic organisms of subtropical waters

Cadmium - a case of mistaken identity

Energy Technology Data Exchange (ETDEWEB)

Taylor, D

1984-05-01

New evidence is presented which describes the impact of cadmium in the environment. Cadmium is a persistent material, although its compounds may undergo a range of chemical changes in the environment. In soluble form cadmium and its compounds are toxic at relatively low concentrations to aquatic animals although their bioconcentrations in such animals is in general low, and there is no evidence of biomagnification. In insoluble form cadmium and its compounds are relatively non-toxic to aquatic animals and are unlikely to be bioconcentrated. As such, cadmium is similar to most other heavy metals. Recent studies indicate that cadmium is not implicated in Itai-Itai disease and does not appear to cause hypertension or cancer. In addition, the accepted critical level in the kidney may have been underestimated. Thus, the hazard to man appears to be considerably less than the original estimates. In view of these data, there seems little justification in treating cadmium in any way differently from the other metals and hence no reason for retaining it on the Black List of the international conventions. 19 references.

Accumulation and elimination of polychlorinated dibenzo-p-dioxins and dibenzofurans in mule ducks.

Science.gov (United States)

Wu, Ting-Wei; Lee, Jai-Wei; Liu, Hsueh-Yen; Lin, Wei-Hsiao; Chu, Chun-Yen; Lin, Sheng-Lun; Chang-Chien, Guo Ping; Yu, Chi

2014-11-01

In Taiwan, a food safety crisis involving a presence of high concentrations of dioxin residues in duck eggs occurred in 2004. The dioxin content in duck meat sampled from supermarkets was also reported to be substantially higher than in products from other farm animals. Despite increased awareness of the potential for contamination and exposure to dioxins, the accumulation and elimination of dioxins in ducks have not been well characterized. In the present study, mule ducks were fed capsules containing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) for 14 days and the trial was continued for another 28 days without PCDD/Fs supplementation. Ducks were sacrificed on the 14th, 28th, and 42nd days from the beginning of administration and samples of abdominal fat, breast, and liver tissue were obtained. The concentrations of PCDD/Fs were analyzed in the samples to investigate their distribution and elimination in various duck tissues. The bioaccumulation of PCDD/Fs in ducks was found to be tissue-dependent. In the abdominal fat, the bioconcentration factor was negatively correlated with the degree of chlorination. Conversely, more chlorinated PCDD/Fs (hexa- or hepta-congeners) were associated with higher bioconcentration in the liver and breast tissue. In terms of the efficiency of PCDD/Fs elimination, the liver was found to be the fastest, followed by the breast and the abdominal fat. The clearance rate positively correlated with the degree of chlorination, as determined by comparing the apparent elimination rate constant (k) of PCDD/Fs in various tissues. Overall, lower k values observed in this study imply that mule ducks have a reduced clearance of PCDD/Fs in comparison with layer and broiler chickens. Copyright © 2014 Elsevier B.V. All rights reserved.

Characterization of elements in marine organisms

International Nuclear Information System (INIS)

Ishii, Toshiaki

1994-01-01

Characterization of elements was carried out to clarify the mechanisms of bioconcentration and the physiological roles of elements in marine organisms. The concentrations of 238 U in fifty-five species of marine organisms were measured by inductively coupled plasma mass spectrometry. The concentrations of 238 U in soft tissues of marine animals ranged from 0.076 to 500ng/g wet wt. Especially, the branchial heart of cephalopod molluscs showed the specific accumulation of 238 U. The concentration factor of the branchial heart of Octopus vulgaris, which indicated the highest value, was calculated to be about 10 3 by comparing it with the concentration of 238 U (3.2 ± 0.2ng/ml) in coastal seawater of Japan. The concentrations of 238 U of twenty species of algae ranged from 10 to 3700ng/g dry wt. (author)

Snapping turtles, a biological screen for PCB's

Energy Technology Data Exchange (ETDEWEB)

Olafsson, P.G.; Bryan, A.M.; Bush, B.; Stone, W.

1983-01-01

Snapping turtles are capable of storing extremely high concentration of organochlorine compounds in their fat without any apparent detrimental effect. This tolerance, to high bioconcentration, permits a wide gradation between the extremes in pollution levels and facilitates the detection of extremely toxic substances present in trace amounts. Consequently snapping turtles provide an excellent biological screen for these compounds.

Experimental validation of geosmin uptake in rainbow trout, Oncorhynchus mykiss (Waldbaum) suggests biotransformation

NARCIS (Netherlands)

Schram, Edward; Schrama, Johan W.; Kooten, van Tobias; Kwadijk, Christiaan J.A.F.; Kampen, Harm; Kampen, Harm; Heul, van de Jan W.; Verreth, Johan A.J.; Murk, Albertinka J.

2018-01-01

The bioconcentration of waterborne geosmin in rainbow trout, Oncorhynchus mykiss (Waldbaum) was assessed. Fifty rainbow trout with a mean (SD) weight of 226.6 (29.0) g and lipid content of 6.2 (0.6) % (w/w) were exposed to geosmin in static water for 0, 2, 4, 6, 8, 12, 24, 36, 48 and 120 hr, with

One-dimensional model of interacting-step fluctuations on vicinal surfaces: Analytical formulas and kinetic Monte Carlo simulations

Science.gov (United States)

Patrone, Paul N.; Einstein, T. L.; Margetis, Dionisios

2010-12-01

We study analytically and numerically a one-dimensional model of interacting line defects (steps) fluctuating on a vicinal crystal. Our goal is to formulate and validate analytical techniques for approximately solving systems of coupled nonlinear stochastic differential equations (SDEs) governing fluctuations in surface motion. In our analytical approach, the starting point is the Burton-Cabrera-Frank (BCF) model by which step motion is driven by diffusion of adsorbed atoms on terraces and atom attachment-detachment at steps. The step energy accounts for entropic and nearest-neighbor elastic-dipole interactions. By including Gaussian white noise to the equations of motion for terrace widths, we formulate large systems of SDEs under different choices of diffusion coefficients for the noise. We simplify this description via (i) perturbation theory and linearization of the step interactions and, alternatively, (ii) a mean-field (MF) approximation whereby widths of adjacent terraces are replaced by a self-consistent field but nonlinearities in step interactions are retained. We derive simplified formulas for the time-dependent terrace-width distribution (TWD) and its steady-state limit. Our MF analytical predictions for the TWD compare favorably with kinetic Monte Carlo simulations under the addition of a suitably conservative white noise in the BCF equations.

Self-Supported Biocarbon-Fiber Electrode Decorated with Molybdenum Carbide Nanoparticles for Highly Active Hydrogen-Evolution Reaction.

Science.gov (United States)

Xiao, Jian; Zhang, Yan; Zhang, Zheye; Lv, Qiying; Jing, Feng; Chi, Kai; Wang, Shuai

2017-07-12

Devising and facilely synthesizing an efficient noble metal-free electrocatalyst for the acceleration of the sluggish kinetics in the hydrogen-evolution reaction (HER) is still a big challenge for electrolytic water splitting. Herein, we present a simple one-step approach for constructing self-supported biocarbon-fiber cloth decorated with molybdenum carbide nanoparticles (BCF/Mo 2 C) electrodes by a direct annealing treatment of the Mo oxyanions loaded cotton T-shirt. The Mo 2 C nanoparticles not only serve as the catalytic active sites toward the HER but also enhance the hydrophilicity and conductivity of resultant electrodes. As an integrated three-dimensional HER cathode catalyst, the BCF/Mo 2 C exhibits outstanding electrocatalytic performance with extremely low overpotentials of 88 and 115 mV to drive a current density of 20 mA cm -2 in alkaline and acidic media, respectively. In addition, it can continuously work for 50 h with little decrease in the cathodic current density in both alkaline and acidic solutions. Even better, self-supported tungsten carbide and vanadium carbide based electrodes also can be prepared by a similar synthesis process. This work will illuminate an entirely new avenue for the preparation of various self-supported three-dimensional electrodes made of transition-metal carbides for various applications.

Mechanistic study on the fluorination of K[B(CN)4] with ClF enabling the high yield and large scale synthesis of K[B(CF3)4] and K[(CF3)3BCN].

Science.gov (United States)

Bernhardt, Eduard; Finze, Maik; Willner, Helge

2011-10-17

The fluorination of K[B(CN)(4)] with ClF is studied by millimolar test reactions in aHF and CH(2)Cl(2) solution and by subsequent identification of intermediates such as B-CF═NCl, B-CF(2)-NCl(2), and B-CF(3) species as well as NCl(3) by (19)F, (11)B NMR, and Raman spectroscopy, respectively. At first one cyano group of K[B(CN)(4)] is converted fast into a CF(3) group, and with increasing fluorination the reaction becomes slower and several intermediates could be observed. On the basis of these results, a synthesis was developed for K[B(CF(3))(4)] on a 0.2 molar scale by treatment of K[B(CN)(4)] diluted in aHF with ClF. The course of the reactions was followed by (i) monitoring the vapor pressure inside the reactor, (ii) observing the heat dissipation during ClF uptake, and (iii) measuring the volume of the released nitrogen gas. Since the fluorination of the last cyano group proceeds very slowly, the selective synthesis of K[(CF(3))(3)BCN] on a 0.2 molar scale is possible, as well. The analysis of the mechanisms, thermodynamics, and kinetics of the fluorination reactions is supported by density functional theory (DFT) calculations.

A Computational Approach to Model Vascular Adaptation During Chronic Hemodialysis: Shape Optimization as a Substitute for Growth Modeling

Science.gov (United States)

Mahmoudzadeh Akherat, S. M. Javid; Boghosian, Michael; Cassel, Kevin; Hammes, Mary

2015-11-01

End-stage-renal disease patients depend on successful long-term hemodialysis via vascular access, commonly facilitated via a Brachiocephalic Fistula (BCF). The primary cause of BCF failure is Cephalic Arch Stenosis (CAS). It is believed that low Wall Shear Stress (WSS) regions, which occur because of the high flow rates through the natural bend in the cephalic vein, create hemodynamic circumstances that trigger the onset and development of Intimal Hyperplasia (IH) and subsequent CAS. IH is hypothesized to be a natural effort to reshape the vessel, aiming to bring the WSS values back to a physiologically acceptable range. We seek to explore the correlation between regions of low WSS and subsequent IH and CAS in patient-specific geometries. By utilizing a shape optimization framework, a method is proposed to predict cardiovascular adaptation that could potentially be an alternative to vascular growth and remodeling. Based on an objective functional that seeks to alter the vessel shape in such a way as to readjust the WSS to be within the normal physiological range, CFD and shape optimization are then coupled to investigate whether the optimal shape evolution is correlated with actual patient-specific geometries thereafter. Supported by the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health (R01 DK90769).

Arsenic uptake by Lemna minor in hydroponic system.

Science.gov (United States)

Goswami, Chandrima; Majumder, Arunabha; Misra, Amal Kanti; Bandyopadhyay, Kaushik

2014-01-01

Arsenic is hazardous and causes several ill effects on human beings. Phytoremediation is the use of aquatic plants for the removal of toxic pollutants from external media. In the present research work, the removal efficiency as well as the arsenic uptake capacity of duckweed Lemna minor has been studied. Arsenic concentration in water samples and plant biomass were determined by AAS. The relative growth factor of Lemna minor was determined. The duckweed had potential to remove as well as uptake arsenic from the aqueous medium. Maximum removal of more than 70% arsenic was achieved atinitial concentration of 0.5 mg/1 arsenic on 15th day of experimental period of 22 days. Removal percentage was found to decrease with the increase in initial concentration. From BCF value, Lemna minor was found to be a hyperaccumulator of arsenic at initial concentration of 0.5 mg/L, such that accumulation decreased with increase in initial arsenic concentration.

A newly found cadmium accumulator-Malva sinensis Cavan

Energy Technology Data Exchange (ETDEWEB)

Zhang Shirong, E-mail: rsz01@163.com [College of Resources and Environment, Sichuan Agricultural University, 46 Xinkang Road, Yaan 625014 (China); Chen Mingying; Li Ting; Xu Xiaoxun; Deng Liangji [College of Resources and Environment, Sichuan Agricultural University, 46 Xinkang Road, Yaan 625014 (China)

2010-01-15

Screening hyperaccumulators and accumulators is a key step in the phytoremediation of soils contaminated by heavy metals. A pot experiment was conducted involving a soil Cd concentration gradient (0, 50, 75, 100, 125, 150, 175, and 200 mg kg{sup -1}) to determine if Malva sinensis Cavan. from two lead-zinc mines in Kangding and Yajiang in western Sichuan, China, is a Cd-hyperaccumulator. The highest Cd concentrations in plant shoots from Kangding and Yajiang were 154.30 and 122.77 mg kg{sup -1}, respectively, at a soil Cd concentration of 200 mg kg{sup -1}. The largest amounts of accumulation in plant shoots from Kangding and Yajiang were 700.5 and 1403.2 {mu}g pot{sup -1}, respectively. The bioconcentration factors in shoots were 0.53-1.03 for Kangding and 0.69-1.25 for Yajiang. Moreover, all translocation factors of plants from the two sites were over 1.0. Therefore, M. sinensis can be classified as a Cd-accumulator or non-standard Cd-hyperaccumulator.

Leaf-age and soil-plant relationships: key factors for reporting trace-elements hyperaccumulation by plants and design applications.

Science.gov (United States)

Losfeld, Guillaume; L'Huillier, Laurent; Fogliani, Bruno; Mc Coy, Stéphane; Grison, Claude; Jaffré, Tanguy

2015-04-01

Relationships between the trace-elements (TE) content of plants and associated soil have been widely investigated especially to understand the ecology of TE hyperaccumulating species to develop applications using TE phytoextraction. Many studies have focused on the possibility of quantifying the soil TE fraction available to plants, and used bioconcentration (BC) as a measure of the plants ability to absorb TE. However, BC only offers a static view of the dynamic phenomenon of TE accumulation. Accumulation kinetics are required to fully account for TE distributions in plants. They are also crucial to design applications where maximum TE concentrations in plant leaves are needed. This paper provides a review of studies of BC (i.e. soil-plant relationships) and leaf-age in relation to TE hyperaccumulation. The paper focuses of Ni and Mn accumulators and hyperaccumulators from New Caledonia who were previously overlooked until recent Ecocatalysis applications emerged for such species. Updated data on Mn hyperaccumulators and accumulators from New Caledonia are also presented and advocate further investigation of the hyperaccumulation of this element. Results show that leaf-age should be considered in the design of sample collection and allowed the reclassification of Grevillea meisneri known previously as a Mn accumulator to a Mn hyperaccumulator.

A comparison of efficient methods for the computation of Born gluon amplitudes

International Nuclear Information System (INIS)

Dinsdale, Michael; Ternick, Marko; Weinzierl, Stefan

2006-01-01

We compare four different methods for the numerical computation of the pure gluonic amplitudes in the Born approximation. We are in particular interested in the efficiency of the various methods as the number n of the external particles increases. In addition we investigate the numerical accuracy in critical phase space regions. The methods considered are based on (i) Berends-Giele recurrence relations, (ii) scalar diagrams, (iii) MHV vertices and (iv) BCF recursion relations

Cyclic volatile methylsiloxane bioaccumulation in flounder and ragworm in the Humber Estuary.

Science.gov (United States)

Kierkegaard, Amelie; van Egmond, Roger; McLachlan, Michael S

2011-07-15

Cyclic volatile methylsiloxanes are being subjected to regulatory scrutiny as possible PBT chemicals. The investigation of bioaccumulation has yielded apparently contradictory results, with high laboratory fish bioconcentration factors on the one hand and low field trophic magnification factors on the other. In this study, octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) were studied along with polychlorinated biphenyls (PCBs) in sediments, ragworm, and flounder from six sites in the Humber Estuary. Bioaccumulation was evaluated using multimedia bioaccumulation factors (mmBAFs) which quantified the fraction of the contaminant present in the aquatic environment that is transferred to the biota. PCB 180, a known strongly bioaccumulative chemical, was used as a benchmark. The mean mmBAF of D5 was about twice that of PCB 180 in both polycheates and flounder, while for D4 it was 6 and 14 times higher, respectively. The mmBAF of D6 was a factor 5-10 lower than that of PCB180. The comparatively strong multimedia bioaccumulation of D4 and D5, even in the absence of biomagnification, was explained by both compounds having a >100 times stronger tendency to partition into lipid rather than into organic carbon, while PCB 180 partitions to a similar extent into both matrices.

Postseismic deformation associated with the 2008 Mw 7.9 Wenchuan earthquake, China: Constraining fault geometry and investigating a detailed spatial distribution of afterslip

Science.gov (United States)

Jiang, Zhongshan; Yuan, Linguo; Huang, Dingfa; Yang, Zhongrong; Chen, Weifeng

2017-12-01

We reconstruct two types of fault models associated with the 2008 Mw 7.9 Wenchuan earthquake, one is a listric fault connecting a shallowing sub-horizontal detachment below ∼20 km depth (fault model one, FM1) and the other is a group of more steeply dipping planes further extended to the Moho at ∼60 km depth (fault model two, FM2). Through comparative analysis of the coseismic inversion results, we confirm that the coseismic models are insensitive to the above two type fault geometries. We therefore turn our attention to the postseismic deformation obtained from GPS observations, which can not only impose effective constraints on the fault geometry but also, more importantly, provide valuable insights into the postseismic afterslip. Consequently, FM1 performs outstandingly in the near-, mid-, and far-field, whether considering the viscoelastic influence or not. FM2 performs more poorly, especially in the data-model consistency in the near field, which mainly results from the trade-off of the sharp contrast of the postseismic deformation on both sides of the Longmen Shan fault zone. Accordingly, we propose a listric fault connecting a shallowing sub-horizontal detachment as the optimal fault geometry for the Wenchuan earthquake. Based on the inferred optimal fault geometry, we analyse two characterized postseismic deformation phenomena that differ from the coseismic patterns: (1) the postseismic opposite deformation between the Beichuan fault (BCF) and Pengguan fault (PGF) and (2) the slightly left-lateral strike-slip motions in the southwestern Longmen Shan range. The former is attributed to the local left-lateral strike-slip and normal dip-slip components on the shallow BCF. The latter places constraints on the afterslip on the southwestern BCF and reproduces three afterslip concentration areas with slightly left-lateral strike-slip motions. The decreased Coulomb Failure Stress (CFS) change ∼0.322 KPa, derived from the afterslip with viscoelastic influence

Characterization of elements in marine organisms

Energy Technology Data Exchange (ETDEWEB)

Ishii, Toshiaki [National Inst. of Radiological Sciences, Nakaminato, Ibaraki (Japan). Nakaminato Lab. Branch Office

1994-03-01

Characterization of elements was carried out to clarify the mechanisms of bioconcentration and the physiological roles of elements in marine organisms. The concentrations of {sup 238}U in fifty-five species of marine organisms were measured by inductively coupled plasma mass spectrometry. The concentrations of {sup 238}U in soft tissues of marine animals ranged from 0.076 to 500ng/g wet wt. Especially, the branchial heart of cephalopod molluscs showed the specific accumulation of {sup 238}U. The concentration factor of the branchial heart of Octopus vulgaris, which indicated the highest value, was calculated to be about 10{sup 3} by comparing it with the concentration of {sup 238}U (3.2 {+-} 0.2ng/ml) in coastal seawater of Japan. The concentrations of {sup 238}U of twenty species of algae ranged from 10 to 3700ng/g dry wt. (author).

The toxicity of a new disinfection by-product, 2,2-dichloroacetamide (DCAcAm), on adult zebrafish (Danio rerio) and its occurrence in the chlorinated drinking water.

Science.gov (United States)

Yu, Shilin; Lin, Tao; Chen, Wei; Tao, Hui

2015-11-01

The detection method of 2,2-dichloroacetamide (DCAcAm), a new disinfection by-product (DBP) in chlorinated drinking water, was established using a gas chromatograph coupled with a micro-electron capture detector. The chlorinated water samples were taken from ten drinking water treatment plants around Yangtze River or Taihu Lake in China. The concentration of DCAcAm was detected ranging from 0.5 to 1.8μg/L in the waterworks around Yangtze River, and 1.5-2.6μg/L around Taihu Lake. The toxicity of DCAcAm on adult zebrafish was assessed by investigating the metabolism damage with multiple metabolic biomarkers and the accumulation capability with bio-concentration factor. The results showed that DCAcAm could cause the acute metabolism damage and was easily accumulated in zebrafish, and should be extremely cautioned. Copyright © 2015 Elsevier Ltd. All rights reserved.

Developing biological and chemical methods for environmental monitoring of DOE waste disposal and storage facilities. Progress report, April 1, 1985--October 30, 1985

International Nuclear Information System (INIS)

1997-01-01

During the first year of this contract great efforts were made to develop methods for (1) characterizing bacteria from soil and sediment, (2) evaluating the ability of single and mixed soil bacterial isolates to, (a) bioconcentrate, (b) biodegrade and/or (c) precipitate inorganic and organic pollutants and (3) expanding current concepts for treating waste in aqueous (i.e. biological waste treatment system) and solid media (i.e. in situ soil (soil) treatment system). The development of the above methods are in the final stages of completion and we have as a result of these efforts isolated from soil (1) a mixed culture which precipitate toxic metals (i.e. mercury cadmium, lead etc.) and (2) single isolates which bioconcentrate a variety of toxic metals. Methods for screening soil bacterial isolates for their ability to concentrate, degrade and/or precipitate environmental pollutants have been developed. The development of those methods will allow the staff at ORRI to quickly screen hundreds of samples in our attempt to isolate bacteria capable of degrading, concentrating and/or precipitating inorganics and organics in aqueous and solid waste. The results of these studies are summarized below

Preliminary Problem Definition Study on Munitions-Related Chemicals.

Science.gov (United States)

1979-04-01

Thorium-230, Radium-226, Lead- 210 and Polonium - 210 by Plants," Radiat. Bot., 10(3), 293-295. Ernst, W. (1968), "Ecological Studies on Plants Grown on...dechlorane in the environment and its bioconcentration and biomagnifica- tion through the food chain. In mammals, dechlorane has been shown to be tei-atogenic...08 5. Phytotoxicity .o......................208 *6. Environmental Fate ....................... 210 7. Availability of Literature for

Modeling the National Ignition Facility neutron imaging system.

Science.gov (United States)

Wilson, D C; Grim, G P; Tregillis, I L; Wilke, M D; Patel, M V; Sepke, S M; Morgan, G L; Hatarik, R; Loomis, E N; Wilde, C H; Oertel, J A; Fatherley, V E; Clark, D D; Fittinghoff, D N; Bower, D E; Schmitt, M J; Marinak, M M; Munro, D H; Merrill, F E; Moran, M J; Wang, T-S F; Danly, C R; Hilko, R A; Batha, S H; Frank, M; Buckles, R

2010-10-01

Numerical modeling of the neutron imaging system for the National Ignition Facility (NIF), forward from calculated target neutron emission to a camera image, will guide both the reduction of data and the future development of the system. Located 28 m from target chamber center, the system can produce two images at different neutron energies by gating on neutron arrival time. The brighter image, using neutrons near 14 MeV, reflects the size and symmetry of the implosion "hot spot." A second image in scattered neutrons, 10-12 MeV, reflects the size and symmetry of colder, denser fuel, but with only ∼1%-7% of the neutrons. A misalignment of the pinhole assembly up to ±175 μm is covered by a set of 37 subapertures with different pointings. The model includes the variability of the pinhole point spread function across the field of view. Omega experiments provided absolute calibration, scintillator spatial broadening, and the level of residual light in the down-scattered image from the primary neutrons. Application of the model to light decay measurements of EJ399, BC422, BCF99-55, Xylene, DPAC-30, and Liquid A suggests that DPAC-30 and Liquid A would be preferred over the BCF99-55 scintillator chosen for the first NIF system, if they could be fabricated into detectors with sufficient resolution.

Hot continent: South America is open for fast growth in the natural gas sector

International Nuclear Information System (INIS)

Reinsch, A. E.

1997-01-01

Opportunities for participation in the rapid expansion of the natural gas sector in South America following privatization and deregulation initiatives, were examined on a country-by-country basis. In Colombia and Venezuela opportunities exist primarily in domestic development of the gas sector, whereas in the countries of the southern cone - Argentina, Bolivia, Brazil, Chile, Paraguay, Peru and Uruguay - the situation is said to be ripe for energy sector integration. Currently, a second regional pipeline link, with a capacity of 129 Bcf/year, is nearing completion, which will carry gas from west Argentina to Santiago, Chile, to supplement the 77 Bcf/year pipeline carrying gas from Bolivia to the Argentine border, where it connects with a trunk line to supply the Buenos Aires market. A Canadian Energy Research Institute study, to be published in the summer of 1997, focuses on the various pipeline links being put forward to integrate the gas resources in the southern cone with existing and potential gas markets. The integration scenarios examined are predicted to reveal both economic and commercial merit for the pipeline corridors. Canadian energy and pipeline companies are said to be well positioned to take advantage of the opportunities resulting from these initiatives, and to help making the vision of an integrated gas pipeline network in the southern cone of South America a reality

Lake Chapala, Mexico: lead distribution in water, sediment and bacteria; Escenarios de la distribucion de plomo en agua, sedimentos y bacterias del lago de Chapala, Mexico

Energy Technology Data Exchange (ETDEWEB)

Hansen, Anne M. [Instituto Mexicano de Tecnologia del Agua, Jiutepec, Morelos (Mexico); Villa-Navia, Adriana [Interventor Ambiental de Occidental de Colombia, Inc. (Colombia); Afferden, Manfred van [Instituto Mexicano de Tecnologia del Agua, Jiutepec, Morelos (Mexico)

2006-04-15

To evaluate the distribution of lead in the natural resources of lake Chapala, the adsorption of this metal in bacteria was analyzed and, through published data and the application of a chemical equilibrium model, the risk associated with the consumption of fish and water was estimated. Adsorption experiments of lead in three bacterial strains and simulations of the distribution of lead in the water-sediment-bacteria system indicate that the distribution of lead in the lake depends on variations of water quality such as suspended solids, lead and biomass concentrations. Considering only the lead contained in the bottom sediments, the simulations suggest that concentrations do not exceed the limits nor the criteria for use and protection of water, sediments, and biota. Considering an additional source of lead that locally increases the concentration by a factor of ten, the amount of lead in water and sediments may exceed these limits. The bioaccumulation of lead in lake Chapala was evaluated through calculation of bioconcentration and biomagnification factors, using simulated and published data on lead in fish (Ayla Jay y Ford, 2001). The results indicate that lead may be concentrated 721 and 6,195 times in bacteria and fish, respectively. Furthermore, bioaccumulation of lead in the lake may occur mainly as bioconcentration in fish rather than biomagnification in the food chain. [Spanish] Para evaluar la distribucion de plomo en los recursos naturales en el lago de Chapala se analizo la adsorcion de este metal en bacterias y, mediante datos publicados en la literatura y modelacion numerica, se estimo el riesgo asociado al consumo de peces y agua. Experimentos de adsorcion en tres cepas de bacterias y simulaciones de la distribucion en un sistema agua-sedimentos-bacterias indican que la distribucion del plomo en el lago depende de variaciones en calidad del agua tales como solidos suspendidos totales, plomo total y biomasa. Considerando unicamente el plomo contenido

A study on possible use of Urtica dioica (common nettle) plant as polonium (210)Po and lead (210)Pb contamination biomonitor in the area of phosphogypsum stockpile.

Science.gov (United States)

Olszewski, Grzegorz; Boryło, Alicja; Skwarzec, Bogdan

2016-04-01

The aim of this study was to test a possible use of Urtica dioica (common nettle) plant as a biomonitor of polonium (210)Po and lead (210)Pb contamination near phosphogypsum stacks by determining concentrations of these radionuclides in samples collected from the area of phosphogypsum stockpile in Wiślinka (northern Poland). The (210)Po and (210)Pb contents in roots depended on their concentrations in soils. Bioconcentration factor values from soil to root of the plant did not depend on (210)Po and (210)Pb contents in soils that leads to the conclusion that different polonium and lead species have different affinities to U. dioica plants. The main sources of both analyzed radionuclides in green parts of plants are wet and dry air deposition and transportation from soil. The values of (210)Po/(210)Pb activity ratio indicate natural origin of these radioisotopes in analyzed plants. (210)Po and (210)Pb concentration in U. dioica roots is negatively weakly correlated with distance from phosphogypsum stockpile.

Contaminant profiles for surface water, sediment, flora and fauna associated with the mangrove fringe along middle and lower eastern Tampa Bay.

Science.gov (United States)

Lewis, M A; Russell, M J

2015-06-15

Contaminant concentrations are reported for surface water, sediment, flora and fauna collected during 2010-2011 from the mangrove fringe along eastern Tampa Bay, Florida. Concentrations of trace metals, chlorinated pesticides, atrazine, total polycyclic aromatic hydrocarbons, and polychlorinated biphenyls were species-, chemical- and location-specific. Contaminants in sediments did not exceed proposed individual sediment quality guidelines. Most sediment quality assessment quotients were less than one indicating the likelihood of no inhibitory effect based on chemical measurements alone. Faunal species typically contained more contaminants than plant species; seagrass usually contained more chemicals than mangroves. Bioconcentration factors for marine angiosperms were usually less than 10 and ranged between 1 and 31. Mercury concentrations (ppm) in blue crabs and fish did not exceed the U.S. Environmental Protection Agency fish tissue criterion of 0.3 and the U.S. Food and Drug Administration action level of 1.0. In contrast, total mercury concentrations in faunal species often exceeded guideline values for wildlife consumers of aquatic biota. Published by Elsevier Ltd.

Plant uptake of pentachlorophenol from sludge-amended soils

International Nuclear Information System (INIS)

Bellin, C.A.; O'Connor, G.A.

1990-01-01

A greenhouse study was conducted to determine the effects of sludge on plant uptake of 14 C-pentachlorophenol (PCP). Plants included tall fescue (Festuca arundinacea Schreb.), lettuce (Latuca sativa L.), carrot (Daucus carota L.), and chile pepper (Capsicum annum L.). Minimal intact PCP was detected in the fescue and lettuce by gas chromatography/mass spectrometry (GC/MS) analysis. No intact PCP was detected in the carrot tissue extracts. Chile pepper was not analyzed for intact PCP because methylene chloride extracts contained minimal 14 C. The GC/MS analysis of soil extracts at harvest suggests a half-life of PCP of about 10 d independent of sludge rate or PCP loading rate. Rapid degradation of PCP in the soil apparently limited PCP availability to the plant. Bioconcentration factors (dry plant wt./initial soil PCP concentration) based on intact PCP were < 0.01 for all crops, suggesting little PCP uptake. Thus, food-chain crop PCP uptake in these alkaline soils should not limit land application of sludge

Mercury, cadmium and lead concentrations in different ecophysiological groups of earthworms in forest soils

International Nuclear Information System (INIS)

Ernst, Gregor; Zimmermann, Stefan; Christie, Peter; Frey, Beat

2008-01-01

Bioaccumulation of Hg, Cd and Pb by eight ecophysiologically distinct earthworm species was studied in 27 polluted and uncontaminated forest soils. Lowest tissue concentrations of Hg and Cd occurred in epigeic Lumbricus rubellus and highest in endogeic Octolasion cyaneum. Soils dominated by Dendrodrilus rubidus possess a high potential of risk of Pb biomagnification for secondary predators. Bioconcentration factors (soil-earthworm) followed the sequence ranked Cd > Hg > Pb. Ordination plots of redundancy analysis were used to compare HM concentrations in earthworm tissues with soil, leaf litter and root concentrations and with soil pH and CEC. Different ecological categories of earthworms are exposed to Hg, Cd and Pb in the topsoil by atmospheric deposition and accumulate them in their bodies. Species differences in HM concentrations largely reflect differences in food selectivity and niche separation. - Accumulation of non-essential heavy metals by earthworms is species-dependent and is affected by soil characteristics in natural forest soils

Grey relational analysis for evaluating the effects of different rates of wine lees-derived biochar application on a plant-soil system with multi-metal contamination.

Science.gov (United States)

Xu, Min; Zhu, Qihong; Wu, Jun; He, Yan; Yang, Gang; Zhang, Xiaohong; Li, Li; Yu, Xiaoyu; Peng, Hong; Wang, Lilin

2018-03-01

In this study, grey relational analysis (GRA) was used to investigate the effects of different application rates of wine lees-derived biochar on a plant-soil system with multi-metal contamination. A pot experiment was conducted to determine rice growth in multi-metal-contaminated soil amended with samples of wine lees-derived biochar, and 47 indicators (including soil properties, microbial activity, and plant physiology) were selected as evaluation indexes to assess the plant-soil system. The results indicated that higher wine lees-derived biochar application rates (2% W/W) were favorable for soil fertility, the bioconcentration factor (BF), and the mobility factor (MF, %) (with the exception of Cr, Zn, and Hg), but an application of 1% produced the highest plant growth, enzymatic activities, and bacterial diversity. The richness of the bacterial communities was reduced in the soil amended with the wine lees-derived biochar. According to the GRA assessment, the 1% application rate of wine lees-derived biochar was more suitable for restoring the holistic plant-soil system than were the application rates of 0, 0.5, and 2% (W/W). Furthermore, this study shows that GRA is a useful method for evaluating plant-soil systems.

Distribution, bioaccumulation and trophic transfer of chlorinated polyfluoroalkyl ether sulfonic acids in the marine food web of Bohai, China.

Science.gov (United States)

Chen, Hong; Han, Jianbo; Cheng, Jiayi; Sun, Ruijun; Wang, Xiaomeng; Han, Gengchen; Yang, Wenchao; He, Xin

2018-06-04

Chlorinated polyfluoroalkyl ether sulfonic acids (Cl-PFESAs) caused great concerns recently as novel fluorinated alternatives. However, information on their bioconcentration, bioaccumulation and biomagnification in marine ecosystems is limited. In this study, 152 biological samples including invertebrates, fishes, seabirds and mammals collected from Bohai Sea of China were analyzed to investigate the residual level, spatial distribution, bioaccumulation and biomagnification of Cl-PFESAs. 6:2 Cl-PFESA was found in concentrations ranging from factors (BAFs) for 6:2 Cl-PFESA ranged from 2.23 to 4.21, implying the bioaccumulation of this compound. The trophic magnification factor (BMF) for 6:2 Cl-PFESA was determined to be 3.37 in the marine food web, indicating biomagnification potential along the marine food chain. Copyright © 2018 Elsevier Ltd. All rights reserved.

Seasonal variation in radiocaesium concentration in willow ptarmigan and rock ptarmigan in central Norway after the Chernobyl fallout

International Nuclear Information System (INIS)

Pedersen, H.C.; Nyboe, S.; Varskog, P.

1998-01-01

Radioactive caesium (20-60 kBq m -2 ) was deposited after the Chernobyl accident in the mountains of central Norway. Two sympatric ptarmigan species, willow ptarmigan Lagopus lagopus and rock ptarmigan L. mutus, inhabit this alpine ecosystem and are important game species. In 1987 and 1988, a study was carried out to try to identify factors affecting radioactive caesium concentration in these birds. Juvenile willow ptarmigan contained more radiocaesium than adults, but the two sexes did not differ in radiocaesium concentration. The radiocaesium concentration of food plants correlated with radiocaesium concentration of rock ptarmigan, and a seasonal variation in radiocaesium concentration of both ptarmigan species was seen. Rock ptarmigan contained more radiocaesium than willow ptarmigan during winter, but not in summer. This difference was related to differences in diet. The bioconcentration factor was 0·4-0·6. The aggregated transfer coefficient was 0·003-0·009 m 2 kg -1 for both species. In spite of the high deposition, the radiocaesium concentration in muscle rarely exceeded the limit recommended for human food consumption (600 Bq kg -1 ). (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Concept of Aided Phytostabilization of Contaminated Soils in Postindustrial Areas.

Science.gov (United States)

Radziemska, Maja; Koda, Eugeniusz; Bilgin, Ayla; Vaverková, Mgdalena D

2017-12-23

The experiment was carried out in order to evaluate the effects of trace element immobilizing soil amendments, i.e., chalcedonite, dolomite, halloysite, and diatomite on the chemical characteristics of soil contaminated with Cr and the uptake of metals by plants. The study utilized analysis of variance (ANOVA), principal component analysis (PCA) and Factor Analysis (FA). The content of trace elements in plants, pseudo-total and extracted by 0.01 M CaCl₂, were determined using the method of spectrophotometry. All of the investigated element contents in the tested parts of Indian mustard ( Brassica juncea L.) differed significantly in the case of applying amendments to the soil, as well as Cr contamination. The greatest average above-ground biomass was observed when halloysite and dolomite were amended to the soil. Halloysite caused significant increases of Cr concentrations in the roots. The obtained values of bioconcentration and translocation factors observed for halloysite treatment indicate the effectiveness of using Indian mustard in phytostabilization techniques. The addition of diatomite significantly increased soil pH. Halloysite and chalcedonite were shown to be the most effective and decreased the average Cr, Cu and Zn contents in soil.

A sensitive and quantitative biosensing method for the determination of γ-ray emitting radionuclides in surface water

International Nuclear Information System (INIS)

Wolterbeek, H.Th.; Meer, A.J.G.M. van der

1996-01-01

A quantitative and sensitive biosensing method has been developed for the determination of γ-ray emitting radionuclides in surface water. The method is based on the concept that at equilibrium the specific radioactivity in the biosensor is equal to the specific radioactivity in water. The method consists of the measurement of both the radionuclide and the element in the biosensor and the determination of the element level in water. This three-way analysis eliminates problems such as unpredictable biosensor behaviour, effects of water elemental composition or further abiotic parameters: what remains is the generally high enrichment (bioaccumulation factor BCF) of elements and radionuclides in the biosensor material. Measurements were performed with floating water plants (Azolla filiculoides Lamk., Spirodela polyrhiza/Lemna sp.) and the fully submerged water plant Ceratophyllum demersum L., which were sampled from ditch water. Concentrations of elements and radionuclides were determined in both water and biosensor plants, using Neutron Activation Analysis (NAA), ICP-MS, and γ-ray spectrometry, respectively. For the latter, both 1 litre samples (Marinelli-geometry) and 1 cm 3 samples (well-type detectors) were applied in measurements. (author)

Bioaccumulation of glyphosate and its formulation Roundup Ultra in Lumbriculus variegatus and its effects on biotransformation and antioxidant enzymes

Energy Technology Data Exchange (ETDEWEB)

Contardo-Jara, Valeska [Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department of Inland Fisheries, Biochemical Regulation, Mueggelseedamm 301, 12587 Berlin (Germany)], E-mail: contardo@igb-berlin.de; Klingelmann, Eva [Technische Universitaet Berlin/Berlin Institute of Technology, Department of Ecology, Chair of Soil Protection, Salzufer 12, 10587 Berlin (Germany)], E-mail: eva.klingelmann@TU-Berlin.de; Wiegand, Claudia [Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Department of Inland Fisheries, Biochemical Regulation, Mueggelseedamm 301, 12587 Berlin (Germany); Humboldt University Berlin, Faculty of Biology, Unter den Linden 6, 10099 Berlin (Germany)], E-mail: cwiegand@igb-berlin.de

2009-01-15

The bioaccumulation potential of glyphosate and the formulation Roundup Ultra, as well as possible effects on biotransformation and antioxidant enzymes in Lumbriculus variegatus were compared by four days exposure to concentrations between 0.05 and 5 mg L{sup -1} pure glyphosate and its formulation. Bioaccumulation was determined using {sup 14}C labeled glyphosate. The bioaccumulation factor (BCF) varied between 1.4 and 5.9 for the different concentrations, and was higher than estimated from log P{sub ow}. Glyphosate and its surfactant POEA caused elevation of biotransformation enzyme soluble glutathione S-transferase at non-toxic concentrations. Membrane bound glutathione S-transferase activity was significantly elevated in Roundup Ultra exposed worms, compared to treatment with equal glyphosate concentrations, but did not significantly differ from the control. Antioxidant enzyme superoxide dismutase was significantly increased by glyphosate but in particular by Roundup Ultra exposure indicating oxidative stress. The results show that the formulation Roundup Ultra is of more ecotoxicological relevance than the glyphosate itself. - Roundup Ultra is of more ecotoxicological relevance than the active ingredient, glyphosate, to Lumbriculus variegatus regarding accumulation potential and enzymatic responses.

Bioaccumulation of glyphosate and its formulation Roundup Ultra in Lumbriculus variegatus and its effects on biotransformation and antioxidant enzymes

International Nuclear Information System (INIS)

Contardo-Jara, Valeska; Klingelmann, Eva; Wiegand, Claudia

2009-01-01

The bioaccumulation potential of glyphosate and the formulation Roundup Ultra, as well as possible effects on biotransformation and antioxidant enzymes in Lumbriculus variegatus were compared by four days exposure to concentrations between 0.05 and 5 mg L -1 pure glyphosate and its formulation. Bioaccumulation was determined using 14 C labeled glyphosate. The bioaccumulation factor (BCF) varied between 1.4 and 5.9 for the different concentrations, and was higher than estimated from log P ow . Glyphosate and its surfactant POEA caused elevation of biotransformation enzyme soluble glutathione S-transferase at non-toxic concentrations. Membrane bound glutathione S-transferase activity was significantly elevated in Roundup Ultra exposed worms, compared to treatment with equal glyphosate concentrations, but did not significantly differ from the control. Antioxidant enzyme superoxide dismutase was significantly increased by glyphosate but in particular by Roundup Ultra exposure indicating oxidative stress. The results show that the formulation Roundup Ultra is of more ecotoxicological relevance than the glyphosate itself. - Roundup Ultra is of more ecotoxicological relevance than the active ingredient, glyphosate, to Lumbriculus variegatus regarding accumulation potential and enzymatic responses

Accumulation and elimination of polychlorinated dibenzo-p-dioxins and dibenzofurans in mule ducks

International Nuclear Information System (INIS)

Wu, Ting-Wei; Lee, Jai-Wei; Liu, Hsueh-Yen; Lin, Wei-Hsiao; Chu, Chun-Yen; Lin, Sheng-Lun; Chang-Chien, Guo Ping; Yu, Chi

2014-01-01

In Taiwan, a food safety crisis involving a presence of high concentrations of dioxin residues in duck eggs occurred in 2004. The dioxin content in duck meat sampled from supermarkets was also reported to be substantially higher than in products from other farm animals. Despite increased awareness of the potential for contamination and exposure to dioxins, the accumulation and elimination of dioxins in ducks have not been well characterized. In the present study, mule ducks were fed capsules containing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) for 14 days and the trial was continued for another 28 days without PCDD/Fs supplementation. Ducks were sacrificed on the 14th, 28th, and 42nd days from the beginning of administration and samples of abdominal fat, breast, and liver tissue were obtained. The concentrations of PCDD/Fs were analyzed in the samples to investigate their distribution and elimination in various duck tissues. The bioaccumulation of PCDD/Fs in ducks was found to be tissue-dependent. In the abdominal fat, the bioconcentration factor was negatively correlated with the degree of chlorination. Conversely, more chlorinated PCDD/Fs (hexa- or hepta-congeners) were associated with higher bioconcentration in the liver and breast tissue. In terms of the efficiency of PCDD/Fs elimination, the liver was found to be the fastest, followed by the breast and the abdominal fat. The clearance rate positively correlated with the degree of chlorination, as determined by comparing the apparent elimination rate constant (k) of PCDD/Fs in various tissues. Overall, lower k values observed in this study imply that mule ducks have a reduced clearance of PCDD/Fs in comparison with layer and broiler chickens. - Highlights: • We describe the accumulation and elimination of PCDD/Fs in mule ducks. • The accumulation of PCDD/Fs in mule ducks was tissue-specific. • The elimination of PCDD/Fs in tissues of mule ducks was congener-specific. • The

Accumulation and elimination of polychlorinated dibenzo-p-dioxins and dibenzofurans in mule ducks

Energy Technology Data Exchange (ETDEWEB)

Wu, Ting-Wei, E-mail: M10126010@mail.npust.edu.tw [Department of Animal Science, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (China); Lee, Jai-Wei, E-mail: joeylee@mail.npust.edu.tw [Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (China); Liu, Hsueh-Yen, E-mail: M9926012@mail.npust.edu.tw [Department of Animal Science, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (China); Lin, Wei-Hsiao, E-mail: M10126011@mail.npust.edu.tw [Department of Animal Science, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (China); Chu, Chun-Yen, E-mail: cychu@mail.npust.edu.tw [Graduate Institute of Animal Vaccine Technology, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (China); Lin, Sheng-Lun, E-mail: sllin100@csu.edu.tw [Supermicro Mass Research and Technology Center, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Dist., Kaohsiung City 83347, Taiwan (China); Center for General Education, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Dist., Kaohsiung City 83347, Taiwan (China); Chang-Chien, Guo Ping, E-mail: guoping@csu.edu.tw [Supermicro Mass Research and Technology Center, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Dist., Kaohsiung City 83347, Taiwan (China); Department of Cosmetics and Fashion styling, Cheng Shiu University, No. 840, Chengcing Road, Niaosong Dist., Kaohsiung City 83347, Taiwan (China); Yu, Chi, E-mail: chiyu@mail.npust.edu.tw [Department of Animal Science, National Pingtung University of Science Technology, No. 1, Shuefu Road, Neipu, Pingtung 91201, Taiwan (China)

2014-11-01

In Taiwan, a food safety crisis involving a presence of high concentrations of dioxin residues in duck eggs occurred in 2004. The dioxin content in duck meat sampled from supermarkets was also reported to be substantially higher than in products from other farm animals. Despite increased awareness of the potential for contamination and exposure to dioxins, the accumulation and elimination of dioxins in ducks have not been well characterized. In the present study, mule ducks were fed capsules containing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) for 14 days and the trial was continued for another 28 days without PCDD/Fs supplementation. Ducks were sacrificed on the 14th, 28th, and 42nd days from the beginning of administration and samples of abdominal fat, breast, and liver tissue were obtained. The concentrations of PCDD/Fs were analyzed in the samples to investigate their distribution and elimination in various duck tissues. The bioaccumulation of PCDD/Fs in ducks was found to be tissue-dependent. In the abdominal fat, the bioconcentration factor was negatively correlated with the degree of chlorination. Conversely, more chlorinated PCDD/Fs (hexa- or hepta-congeners) were associated with higher bioconcentration in the liver and breast tissue. In terms of the efficiency of PCDD/Fs elimination, the liver was found to be the fastest, followed by the breast and the abdominal fat. The clearance rate positively correlated with the degree of chlorination, as determined by comparing the apparent elimination rate constant (k) of PCDD/Fs in various tissues. Overall, lower k values observed in this study imply that mule ducks have a reduced clearance of PCDD/Fs in comparison with layer and broiler chickens. - Highlights: • We describe the accumulation and elimination of PCDD/Fs in mule ducks. • The accumulation of PCDD/Fs in mule ducks was tissue-specific. • The elimination of PCDD/Fs in tissues of mule ducks was congener-specific. • The

The presence and distribution of polycyclic aromatic hydrocarbons and inorganic elements in water and lakebed materials and the potential for bioconcentration in biota at established sampling sites on Lake Powell, Utah and Arizona

Science.gov (United States)

Schonauer, Kurt T.; Hart, Robert J.; Antweiler, Ronald C.

2014-01-01

The National Park Service is responsible for monitoring the effects of visitor use on the quality of water, lakebed material (bottom sediments), and biota, in Lake Powell, Utah and Arizona. A sampling program was begun in 2010 to assess the presence, distribution, and concentrations of organic and inorganic compounds in the water column and bottom sediment. In response to an Environmental Impact Statement regarding personal watercraft and as a continuation from previous studies by the U.S. Geological Survey and the National Park Service, Glen Canyon National Recreation Area, water samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) using semipermeable membrane devices and inorganic elements using a fixed-bottle sampler deployed at established monitoring sites during 2010 and 2011. Lakebed material samples were also analyzed for polycyclic aromatic hydrocarbons and inorganic elements, some of which could be harmful to aquatic biota if present at concentrations above established aquatic life criteria. Of the 44 PAH compounds analyzed, 26 individual compounds were detected above the censoring limit in the water column by semipermeable membrane devices. The highest number of compounds detected were at Lone Rock Beach, Wahweap Marina, Rainbow Bridge National Monument, and Antelope Marina which are all located in the southern part of Lake Powell where visitation and boat use is high. Because PAHs can remain near their source, the potential for bioconcentration is highest near these sites. The PAH compound found in the highest concentration was phenol (5,902 nanograms per liter), which is included in the U.S. Environmental Protection Agency’s priority pollutants list. The dissolved inorganic chemistry of water samples measured at the sampling sites in Lake Powell defined three different patterns of elements: (1) concentrations were similar between sites in the upper part of the lake near Farley Canyon downstream to Halls Crossing Marina, a

On a roll: surges under way in production, reserves, employment and international expansion

International Nuclear Information System (INIS)

Jaremko, G.

2001-01-01

The 2000 survey of the top 126 Canadian oil and gas companies by Oilweek Magazine show a clear improvement in the fundamentals of production and reserves, both at home and abroad. There has been an increase of 8.5 per cent in combined output of oil and gas equivalent to 4.008 million barrels per day, compared to 3.695 million in 1999. Oil production rose 7 per cent to 1.784 million barrels daily, up from 1.665 million a year ago. Gas production climbed by about one billion cubic feet per day, or 7.8 per cent, from 11.87 Bcf to 12.88 Bcf in 2000. Proven oil reserves rose 9.4 per cent to 8.9 billion barrels, while gas inventories climbed by 13.7 per cent to 42.5 trillion cubic feet. Employment figures rose by 9.5 per cent to 35,664 as of December 31, 2000, increasing by 3,100 from a year earlier. Production by employee in 2000 stood at 112.3 barrels of oil equivalent, marginally less (by 1.05 per cent) than in 1999. Foreign production emerged as a major factor in the growth of the Canadian oil and gas industry for the first time in 2000. International output by Canadian firms jumped 24 per cent in 2000 to a combined oil and gas equivalent of 644,514 barrels per day. Domestically, Imperial Oil remained the industry's size benchmark, but by expanding abroad, Alberta Energy Company, Gulf Canada and Nexen also made impressive gains. Statistical data is arranged in tabular form, the top 100 companies being listed alphabetically, ranking them by oil, gas, gas liquids production and reserves, as well as by number of employees and land holdings. Separate listings and rankings are provided for the top 100 natural gas producers, the top 25 natural gas reserves and the top 25 natural gas liquids reserves. A total of 22 companies are ranked on the basis of their international assets (natural gas and liquids production, reserves and land holdings). Employment and land holdings are ranked for 25 companies in each category

Effects of Temperature and X-rays on Plastic Scintillating Fiber and Infrared Optical Fiber.

Science.gov (United States)

Lee, Bongsoo; Shin, Sang Hun; Jang, Kyoung Won; Yoo, Wook Jae

2015-05-11

In this study, we have studied the effects of temperature and X-ray energy variations on the light output signals from two different fiber-optic sensors, a fiber-optic dosimeter (FOD) based on a BCF-12 as a plastic scintillating fiber (PSF) and a fiber-optic thermometer (FOT) using a silver halide optical fiber as an infrared optical fiber (IR fiber). During X-ray beam irradiation, the scintillating light and IR signals were measured simultaneously using a dosimeter probe of the FOD and a thermometer probe of the FOT. The probes were placed in a beaker with water on the center of a hotplate, under variation of the tube potential of a digital radiography system or the temperature of the water in the beaker. From the experimental results, in the case of the PSF, the scintillator light output at the given tube potential decreased as the temperature increased in the temperature range from 25 to 60 °C. We demonstrated that commonly used BCF-12 has a significant temperature dependence of -0.263 ± 0.028%/°C in the clinical temperature range. Next, in the case of the IR fiber, the intensity of the IR signal was almost uniform at each temperature regardless of the tube potential range from 50 to 150 kVp. Therefore, we also demonstrated that the X-ray beam with an energy range used in diagnostic radiology does not affect the IR signals transmitted via a silver halide optical fiber.

Assessing storage adequacy

International Nuclear Information System (INIS)

Amirault, P.

2004-01-01

Government policy encourages the use of natural gas. It is expected that liquefied natural gas (LNG) and Arctic gas will make up 20 to 25 per cent of supply. This presentation provided an outlook of storage value based on a technical analysis by the National Petroleum Counsel (NPC) report. A moderately robust growth is expected in the residential and commercial load which may be partially offset by robust growth in electricity. The net result is an increase in storage requirements. It was concluded that there is a strong case for growth in storage demand but a lack of good sites for additional capacity. This will lead to higher storage values. The NPC sees the need for 1 Tcf more storage use by 2025, of which 700 Bcf will need to come from new storage. In particular, current storage levels may not be sufficient to meet a colder than normal winter, and deliverability is affected by field inventory. Most storage capacity was built before 1985, mostly by regulated entities. It is expected that only 250 to 400 Bcf will be added over the next 25 years in North America. If storage becomes scarce, prices will move to the marginal cost of new additions, and the upper limit on price will be determined by salt cavern storage. An increase of $1.00 in the price of leasing storage would add about $0.11 to the average price of consumed gas. tabs., figs

Carrier Battle Group (CVBG) Homeporting in the Puget Sound Area, Washington State. Volume 1. Chapters 1-12.

Science.gov (United States)

1986-11-01

East Waterway due to gray- water discharges using the Tidal Prism Method. IV-15 .1" 4-9 Marine invertebrate acute toxicity values for .- a tributyltins ...IV-22 4-10 Marine fish acute toxicity values for tributyltins . IV-25 4-11 Other marine data for tributyltins . IV-26 4-12 Summary of bioconcentration...corrosion with copper-based paints. More recently, through fiscal year 1985, only 15 Navy ships nationwide were painted with tributyltin ( TBT ) paints

Applicability and performance evaluation of QSAR models for bioconcentration in fish

DEFF Research Database (Denmark)

Lombardo, A.; Roncaglioni, A.; Rotoumenou, M. I.

2011-01-01

Under the REACH legislation, human and environmental protection requires carefully assessing each compound produced or imported in EU. To reduce the number of animal tests (in particular tests involving vertebrates) and the cost, REACH promotes the use of all existing information and alternative....... It is interesting to notice that the results of the different models do not always overlap. This offers the opportunity to identify strategies for the careful integration of different methods. Besides the use of combination of the results on a purely statistical way, we will address the possibility to define a more...

Transportation tolls, services and capacity : report from TransCanada PipeLines Limited on its changing mainline system

International Nuclear Information System (INIS)

McPherson, J.

2003-01-01

This presentation described the measures that TransCanada PipeLines Limited has taken to change its business model while lowering operating costs. The company is concerned about keeping tolls as low as possible to maintain competitiveness. Demand for pipeline capacity over the next five years is expected to be as high as 1.0 Bcf. Incremental capacity will be required to serve the markets. The market drivers for transportation were described as being reliability, greater price certainty, optionality, and stability in terms of contracts, service and regulations. 1 fig

Activation of 125I-Factor IX and 125I-Factor X: Effect of tissue factor and Factor VII, Factor Xsub(a) and thrombin

International Nuclear Information System (INIS)

Oesterud, B.; Rapaport, S.I.

Activation of Factor IX and Factor X was studied by adding 125 I-Factor IX or 125 I-Factor X to reaction mixtures and quantitating cleavage products by reduced sodium dodecylsulfate gel electrophoresis. Thrombin failed to activate Factors IX or X; Factor Xsub(a) produced insignificant amounts of cleavage products of both factors. In contrast, the reaction product of tissue factor and Factor VII cleaved large amounts of both Factor IX and Factor X in purified systems and in plasma. In incubation mixtures of plasma containing added 125 I-Factor IX or 125 I-Factor X, tissue factor and Ca 2+ ions, the percentage of total radioactivity in the heavy chain peak of 125 I-IXsub(a) and the heavy chain of 125 I-Xsub(a) increased at a similar rate. When the tissue factor was diluted, similar curves were obtained for percent cleavage of 125 I-Factor IX and percent cleavage of 125 I-Factor X plotted against tissue factor concentration. These findings support the hypothesis that activation of Factor IX by the tissue factor-Factor VII reaction product represents a physiologically significant step in normal haemostasis. (author)

Estimate of uptake and translocation of emerging organic contaminants from irrigation water concentration in lettuce grown under controlled conditions.

Science.gov (United States)

Hurtado, Carlos; Domínguez, Carmen; Pérez-Babace, Lorea; Cañameras, Núria; Comas, Jordi; Bayona, Josep M

2016-03-15

The widespread distribution of emerging organic contaminants (EOCs) in the water cycle can lead to their incorporation in irrigated crops, posing a potential risk for human consumption. To gain further insight into the processes controlling the uptake of organic microcontaminants, Batavia lettuce (Lactuca sativa) grown under controlled conditions was watered with EOCs (e.g., non-steroidal anti-inflammatories, sulfonamides, β-blockers, phenolic estrogens, anticonvulsants, stimulants, polycyclic musks, biocides) at different concentrations (0-40μgL(-1)). Linear correlations were obtained between the EOC concentrations in the roots and leaves and the watering concentrations for most of the contaminants investigated. However, large differences were found in the root concentration factors ( [Formula: see text] =0.27-733) and leaf translocation concentration factors ( [Formula: see text] =0-3) depending on the persistence of the target contaminants in the rhizosphere and the specific physicochemical properties of each one. With the obtained dataset, a simple predictive model based on a linear regression and the root bioconcentration and translocation factors can be used to estimate the concentration of the target EOCs in leaves based on the dose supplied in the irrigation water or the soil concentration. Finally, enantiomeric fractionation of racemic ibuprofen from the initial spiking mixture suggests that biodegradation mainly occurs in the rhizosphere. Copyright © 2015 Elsevier B.V. All rights reserved.

Adaptation and detoxification mechanisms of Vetiver grass (Chrysopogon zizanioides) growing on gold mine tailings.

Science.gov (United States)

Melato, F A; Mokgalaka, N S; McCrindle, R I

2016-01-01

Vetiver grass (Chrysopogon zizanioides) was investigated for its potential use in the rehabilitation of gold mine tailings, its ability to extract and accumulate toxic metals from the tailings and its metal tolerant strategies. Vetiver grass was grown on gold mine tailings soil, in a hothouse, and monitored for sixteen weeks. The mine tailings were highly acidic and had high electrical conductivity. Vetiver grass was able to grow and adapt well on gold mine tailings. The results showed that Vetiver grass accumulated large amounts of metals in the roots and restricted their translocation to the shoots. This was confirmed by the bioconcentration factor of Zn, Cu, and Ni of >1 and the translocation factor of <1 for all the metals. This study revealed the defense mechanisms employed by Vetiver grass against metal stress that include: chelation of toxic metals by phenolics, glutathione S-tranferase, and low molecular weight thiols; sequestration and accumulation of metals within the cell wall that was revealed by the scanning electron microscopy that showed closure of stomata and thickened cell wall and was confirmed by high content of cell wall bound phenolics. Metal induced reactive oxygen species are reduced or eliminated by catalase, superoxide dismutase and peroxidase dismutase.

Phytoremediation potential of transplanted bare-root seedlings of trees for lead/zinc and copper mine tailings.

Science.gov (United States)

Shi, Xiang; Chen, Yi-Tai; Wang, Shu-Feng; Pan, Hong-Wei; Sun, Hai-Jing; Liu, Cai-Xia; Liu, Jian-Feng; Jiang, Ze-Ping

2016-11-01

Selecting plant species that can overcome unfavorable conditions and increase the recovery of degraded mined lands remains a challenge. A pot experiment was conducted to evaluate the feasibility of using transplanted tree seedlings for the phytoremediation of lead/zinc and copper mine tailings. One-year-old bare-root of woody species (Rhus chinensis Mill, Quercus acutissima Carruth, Liquidambar formosana Hance, Vitex trifolia Linn. var. simplicifolia Cham, Lespedeza cuneata and Amorpha fruticosa Linn) were transplanted into pots with mine tailings and tested as potential metal-tolerant plants. Seedling survival, plant growth, root trait, nutrient uptake, and metal accumulation and translocation were assessed. The six species grew in both tailings and showed different tolerance level. A. fruticosa was highly tolerant of Zn, Pb and Cu, and grew normally in both tailings. Metal concentrations were higher in the roots than in the shoots of the six species. All of the species had low bioconcentration and translocation factor values. However, R. chinensis and L. formosana had significantly higher translocation factor values for Pb (0.88) and Zn (1.78) than the other species. The nitrogen-fixing species, A. fruticosa, had the highest tolerance and biomass production, implying that it has great potential in the phytoremediation of tailing areas in southern China.

Composted biosolids and treated wastewater as sources of pharmaceuticals and personal care products for plant uptake: A case study with carbamazepine.

Science.gov (United States)

Ben Mordechay, Evyatar; Tarchitzky, Jorge; Chen, Yona; Shenker, Moshe; Chefetz, Benny

2018-01-01

Irrigation with treated wastewater (TWW) and application of biosolids to arable land expose the agro-environment to pharmaceuticals and personal care products (PPCPs) which can be taken up by crops. In this project, we studied the effect of a carrier medium (e.g., biosolids and TWW) on plant (tomato, wheat and lettuce) uptake, translocation and metabolism of carbamazepine as a model for non-ionic PPCPs. Plant uptake and bioconcentration factors were significantly lower in soils amended with biosolids compared to soils irrigated with TWW. In soils amended with biosolids and irrigated with TWW, the bioavailability of carbamazepine for plant uptake was moderately decreased as compared to plants grown in soils irrigated with TWW alone. While TWW acts as a continuous source of PPCPs, biosolids act both as a source and a sink for these compounds. Moreover, it appears that decomposition of the biosolids in the soil after amendment enhances their adsorptive properties, which in turn reduces the bioavailability of PPCPs in the soil environment. In-plant metabolism of carbamazepine was found to be independent of environmental factors, such as soil type, carrier medium, and absolute amount implemented to the soil, but was controlled by the total amount taken up by the plant. Copyright © 2017 Elsevier Ltd. All rights reserved.

Levels of Platinum Group Metals in Selected Species (Sarotherodon melanotheron, Chonophorus lateristriga, Macrobrachium vollenhovenii and Crassostrea tulipa in Some Estuaries and Lagoons Along the Coast of Ghana

Directory of Open Access Journals (Sweden)

D. K. Essumang

2010-01-01

Full Text Available The use of some biota as bioindicators of heavy metal pollution has been demonstrated as particularly adequate due to their capacity of bioconcentration. This study evaluated the levels of platinum group metals (PGMs in some selected species along the coastal belt of Ghana, using the neutron activation analysis (NAA method. The result was processed to evaluate pollution indices in order to map the distribution of the metals in those species in the lagoons and estuaries along the costal belt of Ghana. The analysis showed significant levels of all PGMs in blackchin tilapia (Sarotherodon melanotheron Cichlidae, brown goby (Chonophorus lateristriga Gobiidae, shrimp (Macrobrachium vollenhovenii Palaemonidae, and mangrove oysters (Crassostrea tulipa Ostreidae in the lagoons and river Pra estuary. However, the oysters showed an elevated mean concentration of 0.13 μ/g (dry weight Pd. From the pollution indices, most of the sampling sites registered mean contamination factor (CF values between 1.20 and 3.00 for Pt, Pd, and Rh. The pollution load index (PLI conducted also gave an average pollution index between 0.79 and 2.37, indicating progressive contamination levels. The results revealed that anthropogenic sources, industrial and hospital effluent, etc., together with vehicular emissions, could be the contributing factors to the deposition of PGMs along the Ghanaian coast.

Genotypic variation and mechanism in uptake and translocation of perfluorooctanoic acid (PFOA) in lettuce (Lactuca sativa L.) cultivars grown in PFOA-polluted soils.

Science.gov (United States)

Xiang, Lei; Chen, Lei; Yu, Le-Yi; Yu, Peng-Fei; Zhao, Hai-Ming; Mo, Ce-Hui; Li, Yan-Wen; Li, Hui; Cai, Quan-Ying; Zhou, Dong-Mei; Wong, Ming-Hung

2018-05-02

The cultivation of crop cultivars with low pollutant accumulation is an important strategy to reduce the potential health risks of food produced from polluted soils. In this study, we identified three loose-leaf lettuce cultivars with low accumulation of perfluorooctanoic acid (PFOA), a highly toxic and persistent organic pollutant. PFOA concentrations in the shoots of low-PFOA cultivars were 3.7-5.5-fold lower than those of high-PFOA cultivars. The identification of low-PFOA cultivars could contribute to ensuring food safety despite cultivation in highly polluted soils (1 mg/kg) based on the tolerable daily PFOA intake (1.5 μg/kg/d). We detected lower desorbing fractions of PFOA in rhizosphere soil, lower bioconcentration factors, and higher distribution in the cell walls and organelles of roots in low-PFOA cultivars, all of which are key factors in limiting PFOA uptake and translocation from soil to shoots, than in high-PFOA cultivars. This study reveals the mechanism of PFOA uptake from soil to crop and lays a foundation for establishing a cost-effective strategy to plant crops in polluted soil and reduce exposure risk due to persistent organic pollutants in crops. Copyright © 2018 Elsevier B.V. All rights reserved.

Phytoaccumulation of Heavy Metals in Natural Vegetation at the Municipal Wastewater Site in Abbottabad, Pakistan.

Science.gov (United States)

Irshad, Muhammad; Ruqia, Bibi; Hussain, Zahid

2015-01-01

Heavy metal accumulation in crops and soils from wastewater irrigation poses a significant threat to the human health. A study was carried out to investigate the removal potential of heavy metals (HM) by native plant species, namely Cannabis sativa L., Chenopodium album L., Datura stramonium L., Sonchus asper L., Amaranthus viridus L., Oenothera rosea (LHer), Xanthium stramonium L., Polygonum macalosa L., Nasturtium officinale L. and Conyza canadensis L. growing at the municipal wastewater site in Abbottabad city, Pakistan. The HM concentrations varied among plants depending on the species. Metal concentrations across species varied in the order iron (Fe) > zinc (Zn) > chromium (Cr) > nickel (Ni) > cadmium (Cd). Majority of the species accumulated more HM in roots than shoots. Among species, the concentrations (both in roots and shoots) were in the order C. sativa > C. album > X. stramonium > C. canadensis > A. viridus > N. officinale > P. macalosa > D. stramonium > S. asper > O. rosea. No species was identified as a hyperaccumulator. All species exhibited a translocation factor (TF) less than 1. Species like C. sativa, C. album and X. stramonium gave higher (> 1) biological concentration factor (BCF) and biological accumulation coefficient (BAC) especially for Fe, Cr and Cd than other species. Higher accumulation of heavy metals in these plant species signifies the general application of these species for phytostabilization and phytoextraction of HM from polluted soils.

Heavy metal contamination and accumulation in soil and wild plant species from industrial area of Islamabad, Pakistan

International Nuclear Information System (INIS)

Malik, R.N.; Husain, S.Z.; Nazir, I.

2010-01-01

This study was designed to assess total contents of 6 toxic metals viz., Pb, Cu, Zn, Co, Ni, and Cr in the soil and plant samples of 16 plant species collected from industrial zone of Islamabad, Pakistan. The concentration, transfer and accumulation of metals from soil to roots and shoots was evaluated in terms of Biological Concentration Factor (BCF), Translocation Factor (TF) and Bioaccumulation Coefficient (BAC). Total metal concentrations of Pb, Zn, Cu, Co, Ni, and Cr in soils varied between 2.0-29.0, 61.9-172.6, 8.9 to 357.4, 7.3-24.7, 41.4-59.3, and 40.2-927.2 mg/kg. Total metal concentrations pattern in roots were: Cu>Cr>Zn>Ni>Pb>Co. Grasses showed relatively higher total Zn concentration. Accumulation of Cu was highest in shoots followed by Zn, Cr, Pb, Co and Ni. None of plant species were identified as hyper accumulator; however, based on BCFs, TFs, and BACs values, most of the studied species have potential for phyto stabilization and phyto extraction. Parthenium hysterophoirus L., and Amaranthus viridis L., is suggested for phytoextraction of Pb and Ni, whereas, Partulaca oleracea L., Brachiaria reptans (L.) Gard. and Hubb., Solanum nigrum L., and Xanthium stromarium L., for hytostabilization of soils contaminated with Pb and Cu. (author)