WorldWideScience

Sample records for contaminant migration potential

  1. Characterization of Contaminant Migration Potential Through In-Place Sediment Caps

    Science.gov (United States)

    2011-06-01

    grab. Extraction and analysis of sediment/cap material used pesticide -grade organic solvents obtained from Fisher Scientific (Pittsburgh, PA). The 16...34Controlled Field Release of a Bioluminescent Genetically Engineered  Microorganism  for  Bioremediation  Process Monitoring and Control." Environmental Science...role of sorbent amendments in enhancing cap performance. Laboratory column experiments were performed using contaminated sediments and capping

  2. Characterisation of contamination migration in the workplace

    International Nuclear Information System (INIS)

    Boulaud, D.; Laborde, J.C.; Pourprix, M.

    1994-01-01

    The Institute for Nuclear Safety and Protection (IPSN) has developed a procedure for characterising airborne contamination between processes and the workplace in nuclear facilities. It was initially intended to use this process to validate operator choices concerning the monitoring of indoor air contamination (personnel monitoring, and environmental detection at fixed locations), but also to optimise the fundamental parameters which have a more or less direct influence on potential exposure of staff in the workplace (at the same time optimising the contamination source, close confinement, process ventilation and general ventilation). In practice, the methods used to obtain these expert appraisals were usually based on experiments carried out in situ: (i) characterisation of aerosol contamination by accurate measurement of the nature, concentration and particle size distribution at various locations; (ii) characterisation of the migration of contamination by precise measurement involving gas and/or particle tracing techniques. In parallel with these experiments, a considerable effort was made to develop and qualify computer codes capable of predicting or estimating the migration of contamination through complex ventilated areas, by means of both fluid mechanics and aerosol science. (Author)

  3. Water and contaminant movement: migration barriers

    International Nuclear Information System (INIS)

    Lane, L.J.; Nyhan, J.W.

    1984-11-01

    Migration barriers are used in shallow land burial facilities to slow or stop the movement of water and contaminants and are discussed here as a single component embedded in a complex environmental system. Analytical solutions to solute transport equations are used to approximate the behavior of migration barriers and to derive design criteria for control of subsurface water and contaminant migration. Various types of migration barriers are compared and design recommendations are made for shallow land burial trench caps and liners. Needed improvements and suggested field experiments for future designs of migration barriers are then discussed relative to the management of low-level radioactive wastes

  4. Experiments to determine the migration potential for water and contaminants in shallow land burial facilities design, emplacement, and preliminary results

    International Nuclear Information System (INIS)

    DePoorter, G.L.; Abeele, W.V.; Burton, B.W.

    1982-01-01

    Leaching and transport of radionuclides by water has been a primary mode of radioactive contamination from low-level radioactive waste disposal facilities. Similarly, the infiltration of water into nonradioactive hazardous waste disposal facilities has resulted in the movement of contaminants out of these disposal facilities. Although there have been many laboratory studies on water movement and contaminant transport, there is a need for more large scale field experiments. Large scale field experiments are necessary to (1) measure hydraulic conductivities on a scale typical of actual shallow land burial facilities and hazardous waste disposal facilities, (2) allow comparisons to be made between full scale and laboratory measurements, (3) verify the applicability of calculational methods for determining unsaturated hydraulic conductivities from water retention curves, and (4) for model validation. Experiments that will provide the information to do this are described in this paper

  5. Mechanisms of contaminant migration from grouted waste

    International Nuclear Information System (INIS)

    Magnuson, S.O.; Yu, A.D.

    1992-01-01

    Low-level radioactive decontaminated salt solution is generated at the Savannah River Site (SRS) from the In-Tank Precipitation process. The solution is mixed with cement, slag, and fly ash, to form a grout, termed ''Saltstone'', that will be disposed in concrete vaults at the Saltstone Disposal Facility (SDF) [1]. Of the contaminants in the Saltstone, the greatest concern to SRS is the potential release of nitrate to the groundwater because of the high initial nitrate concentration (0.25 g/cm 3 ) in the Saltstone and the low Safe Drinking Water Act (SDWA) maximum contaminant level (MCL) of 44 mg/L. The SDF is designed to allow a slow, controlled release over thousands of years. This paper addresses a modeling study of nitrate migration from intact non-degraded concrete vaults in the unsaturated zone for the Radiological Performance Assessment (PA) of the SRS Saltstone Disposal Facility [3]. The PA addresses the performance requirements mandated by DOE Order 5820.2A [4

  6. Effects of sorption behaviour on contaminant migration

    International Nuclear Information System (INIS)

    Melnyk, T.W.

    1985-11-01

    The effects of sorption behaviour on contaminant migration in groundwater systems are varied. Retardation of migration and dispersive effects can vary widely and contaminant concentration profiles can take a number of different shapes. This report examines the nature of some of these effects, especially those due to sorption behaviours that are dependent on the concentration of the contaminant in the groundwater. The effects are calculated using, in most cases, analytical solutions to the chemical equations imbedded in a simple reaction-cell or box-model transport algorithm. The hydrogeological parameters are held constant, and radioactive decay and hydrodynamic dispersion are excluded. A general discussion of the role of sorption equations in transport modelling is followed by presentation of migration results for a number of models of sorption behaviour varying from linear isotherms, Langmuir, Freundlich and ion-exchange isotherms, to precipitation reactions and multiple-site sorption reactions. The results are compared and general conclusions are drawn about the various migration behaviours calculated. The conclusions are that equilibrium sorption of trace contaminants can be modelled with linear isotherms (constant distribution coefficients or constant retardation factors) but the evaluation and extrapolation of the distribution coefficient are not easy. Nonlinear isotherms lead to unsymmetrical migration fronts. A comparison of Freundlich and linear isotherms is made. Sorption/desorption kinetic factors can be significant on the time scale of laboratory experiments and can cause large dispersive effects. Slow but important reactions can be missed altogether. Precipitation or mineralization behaviour cannot be modelled with constant distribution coefficients. Also, mineralization reactions can be kinetically slow even on the geological time scale. 89 refs

  7. Nanoparticles migration in fractured rocks and affects on contaminant migration

    Science.gov (United States)

    Missana, Tiziana; Garcia-Gutierrez, Miguel; Alonso, Ursula

    2014-05-01

    In previous studies, the transport behavior of artificial (gold and latex) and natural (smectite clay) colloids, within a planar fracture in crystalline rock, was analyzed. In order to better understand the effects of colloid size, shape and surface charge on nanoparticle migration and especially on filtration processes on natural rock surfaces, different clay colloids and oxide nanoparticles were selected and their transport studied as a function of the residence time. In all the cases, (a fraction of) the nanoparticles travelled in the fracture as fast as or faster than water (with a retardation factor, Rf ≤ 1) and the observed Rf, was related to the Taylor dispersion coefficient, accounting for colloid size, water velocity and fracture width. However, under most of the cases, in contrast to the behavior of a conservative tracer, colloids recovery was much lower than 100 %. Differences in recovery between different nanoparticles, under similar residence times, were analyzed. In order to evaluate the possible consequences, on contaminant migration, of the presence of nanoparticles in the system, transport tests were carried out with both colloids and sorbing radionuclides. The overall capacity for colloids of enhancing radionuclide migration in crystalline rock fractures is discussed. Acknowledgments: The research leading to these results received funding from EU FP7/2007-2011 grant agreement Nº 295487 (BELBAR, Bentonite Erosion: effects on the Long term performance of the engineered Barrier and Radionuclide Transport) and by the Spanish Government under the project NANOBAG (CTM2011-2797).

  8. Family migration and relative earnings potentials

    DEFF Research Database (Denmark)

    Foged, Mette

    2016-01-01

    of husband centered migration. Couples are more likely to migrate if household earnings potential is disproportionally due to one partner, and families react equally strongly to a male and a female relative advantage in educational earnings potential. These results are driven by households with a strong......A unitarian model of family migration in which families may discount wives’ private gains is used to derive testable predictions regarding the type of couples that select into migrating. The empirical tests show that gender neutral family migration cannot be rejected against the alternative...

  9. Migration behavior of landfill leachate contaminants through alternative composite liners

    Energy Technology Data Exchange (ETDEWEB)

    Varank, Gamze, E-mail: gvarank@yildiz.edu.tr; Demir, Ahmet, E-mail: ahmetd@yildiz.edu.tr; Top, Selin, E-mail: stop@yildiz.edu.tr; Sekman, Elif, E-mail: esekman@yildiz.edu.tr; Akkaya, Ebru, E-mail: ekoca@yildiz.edu.tr; Yetilmezsoy, Kaan, E-mail: yetilmez@yildiz.edu.tr; Bilgili, M. Sinan, E-mail: mbilgili@yildiz.edu.tr

    2011-08-01

    Four identical pilot-scale landfill reactors with different alternative composite liners were simultaneously operated for a period of about 540 days to investigate and to simulate the migration behaviors of phenolic compounds (phenol, 2-CP, 2-MP, 3-MP, 4-MP, 2-NP, 4-NP, 2,4-DNP, 2,4-DCP, 2,6-DCP, 2,4,5-TCP, 2,4,6-TCP, 2,3,4,6-TeCP, PCP) and heavy metals (Pb, Cu, Zn, Cr, Cd, Ni) from landfill leachate to the groundwater. Alternative landfill liners of four reactors consist of R1: Compacted clay liner (10 cm + 10 cm, k = 10{sup -8} m/sn), R2: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm + 10 cm, k = 10{sup -8} m/sn), R3: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm, k = 10{sup -8} m/sn) + bentonite liner (2 cm) + compacted clay liner (10 cm, k = 10{sup -8} m/sn), and R4: Geomembrane (2 mm HDPE) + compacted clay liner (10 cm, k = 10{sup -8} m/sn) + zeolite liner (2 cm) + compacted clay liner (10 cm, k = 10{sup -8} m/sn). Wastes representing Istanbul municipal solid wastes were disposed in the reactors. To represent bioreactor landfills, reactors were operated by leachate recirculation. To monitor and control anaerobic degradation in the reactors, variations of conventional parameters (pH, alkalinity, chloride, conductivity, COD, TOC, TKN, ammonia and alcaly metals) were also investigated in landfill leachate samples. The results of this study showed that about 35-50% of migration of organic contaminants (phenolic compounds) and 55-100% of migration of inorganic contaminants (heavy metals) to the model groundwater could be effectively reduced with the use of bentonite and zeolite materials in landfill liner systems. Although leachate contaminants can reach to the groundwater in trace concentrations, findings of this study concluded that the release of these compounds from landfill leachate to the groundwater may potentially be of an important environmental concern based on the experimental findings. - Research highlights: {yields} Migration of

  10. Computer modelling of contaminant migration in natural disperse media

    International Nuclear Information System (INIS)

    Kundas, S.P.; Gishkelyuk, I.A.; Khil'ko, O.S.

    2012-01-01

    The theoretical foundations for modeling of the contaminants migration in natural disperses media taking into account interconnected heat and moisture transport are developed. The calculation of mass transfer parameters based on adsorption isotherms of water and thermodynamic equations in the developed mathematical models. The artificial neural networks use to predict migration of contaminants in natural disperse media is proposed. The developed software package is presented and results of practical application of models and software are discussed. (authors)

  11. Radionuclide migration in the Chernobyl contamination zone

    International Nuclear Information System (INIS)

    Golosov, V.N.; Panin, A.V.; Ivanova, N.N.

    1998-01-01

    It is well known that fallout of 137 Cs reaching the land soils with precipitation was rapidly and tightly sorbed to the fine fraction of sediment or soils. The majority of the 137 Cs is retained in the top few centimetres of the soil or sediment profiles (Loughran et al, 1993, Owens et al, 1996). In the absence of strong variations in precipitation over a relatively small area the total bomb-derived 137 Cs fallout can assumed to be spatial uniform. The Chernobyl 137 Cs fallout was mostly connected with one or two rains. So the spatial variability of this 137 Cs can be higher. Furthermore because the explosion on the Chernobyl nuclear plant happen together with fire, a lot of ashes particles with radionuclide were distributed within vast areas. So even microvariability of Chernobyl 137 Cs can be very high in some places. The horizontal migration of 137 Cs connects with soil erosion processes that dominate on the agricultural lands of the Central Russia. The main goal of this investigation is to evaluate the caesium-137 horizontal and vertical migration within typical landscape of the Central Russia 11 years after the Chernobyl accident

  12. Student Migration Potential: The Case of Bulgaria

    OpenAIRE

    Valentina Makni

    2011-01-01

    Transnational student mobility is a major factor, which plays an ambiguous role in the dynamic process of international highly skilled migration. In this paper we try to attempt an approximate profile of the potential migrant student in Bulgaria, according to the migration incentives, intentions and expectations of highly educated young people from six reputable universities in the country. For this purpose a sample study is applied based on binary logistic regression analysis. Some of the co...

  13. Modeling Contamination Migration on the Chandra X-Ray Observatory - III

    Science.gov (United States)

    O'Dell, Stephen L.; Swartz, Douglas A.; Tice, Neil W.; Plucinsky, Paul P.; Grant, Catherine E.; Marshall, Herman L.; Vikhlinin, Alexy A.; Tennant, Allyn F.; Dahmer, Matthew T.

    2015-01-01

    During its first 16 years of operation, the cold (about -60 C) optical blocking filter of the Advanced CCD Imaging Spectrometer (ACIS), aboard the Chandra X-ray Observatory, has accumulated a growing layer of molecular contamination that attenuates low-energy x rays. Over the past few years, the accumulation rate, spatial distribution, and composition have changed. This evolution has motivated further analysis of contamination migration within and near the ACIS cavity, in part to evaluate potential bake-out scenarios intended to reduce the level of contamination. Keywords: X-ray astronomy, CCDs, contamination, modeling and simulation, spacecraft operations

  14. A generic model of contaminant migration from uranium tailings impoundments

    International Nuclear Information System (INIS)

    Shepherd, T.A.; Brown, S.E.

    1982-01-01

    This paper presents an analytical hydrogeochemical model based upon acid consumption-neutralization front movement. The development of contaminant plumes is discussed and distinct zones within these plumes are identified and characterized. The most important process influencing the rate and extent of contaminant migration at acid-leach uranium tailings impoundments is the neutralization of seepage water by soils along ground water flow paths. The chemical characteristics of the ground water is determined in order to identify and characterize zones within migrating plumes of tailings-derived water. It is concluded that the characterization of specific zones is useful in the interpretation of existing conditions, in the evaluation of future migration, and in the determination of appropriate models for the specific situation

  15. The Patroon Creek Contamination Migration Investigation

    International Nuclear Information System (INIS)

    Dufek, K.; Zafran, A.; Moore, J.T.

    2006-01-01

    Shaw performed a Site Investigation (SI) for sediment within the Unnamed Tributary of the Patroon Creek, a section of the Patroon Creek, and the Three Mile Reservoir as part of the overall contract with the United States Army Corps of Engineers (USACE) to remediate the Colonie Formerly Utilized Sites Remedial Action Program (FUSRAP) Site. The Unnamed Tributary formerly flowed through the former Patroon Lake, which was located on the main site property and was used as a landfill for radiological and chemical wastes. The objective of the investigation was to determine the absence/presence of radioactive contamination within the three Areas of Concern (AOC). In order to accomplish this objective, Shaw assembled a team to produce a Technical Memorandum that provided an in-depth understanding of the environmental conditions related to the Patroon Creek. Upon completion and analysis of the Technical Memorandum, a Conceptual Site Model (CSM) was constructed and a Technical Planning Program (TPP) was held to develop a Sediment Investigation Work Plan and Sediment Investigation Sampling and Analysis Plan. A total of 32 sample locations were analyzed using on-site direct gamma scans with a Pancake Geiger-Mueller (PGM) instrument for screening purposes and samples were analyzed at on-site and off-site laboratories. The highest interval from each core scan was selected for on-site analysis utilizing a High Purity Germanium (HPGe) detector. Eight of these samples were sent off-site for gamma/alpha spectroscopy confirmation. The data collected during the SI indicated that the U-238 cleanup criterion was exceeded in sediment samples collected from two locations within the Unnamed Tributary but not in downstream sections of Patroon Creek or Three Mile Reservoir. Future actions for impacted sediment in the Unnamed Tributary will be further evaluated. Concentrations of U-238 and Th-232 in all other off-site sediment samples collected from the Unnamed Tributary, Patroon Creek, and

  16. Experiments to determine the migration potential for water and contaminants in shallow land-burial facilities: design, emplacement, and preliminary results

    International Nuclear Information System (INIS)

    DePoorter, G.L.; Abeele, W.V.; Burton, B.W.

    1982-01-01

    Although there have been many laboratory studies on water movement and contaminant transport, there is a need for more large scale field experiments. Large scale field experiments are necessary to (1) measure hydraulic conductivities on a scale typical of actual shallow land burial facilities and hazardous waste disposal facilities, (2) allow comparisons to be made between full scale and laboratory measurements, (3) verify the applicability of calculational methods for determining unsaturated hydraulic conductivities from water retention curves, and (4) for model validation. Experiments that will provide the information to do this are described in this paper. The results of these experiments will have applications for both the shallow land burial of low level radioactive wastes and the disposal of hazardous chemical wastes. These experiments will provide results that can be used in model verification for system performance. This type of data on experiments done at this scale has not been available, and are necessary for validating unsaturated transport models and other models used to predict long term system performance. Even though these experiments are done on crushed Bandelier Tuff, most models use physical properties of the backfill material such as density, porosity, and water retention curves. For this reason, once the models are validated in these experiments, they can be applied with confidence to other materials as long as the material properties are well characterized. In addition, from known water movement rates, calculable from the results of these experiments, requirements for other parts of the system such as liners, water diversion systems, and system cap requirements can be determined. Lastly, the results of these experiments and their use in model verification will provide a sound scientific basis on which to base decisions on system requirements and system design

  17. Modeling the migration of radioactive contaminants in groundwater of in situ leaching uranium mine

    International Nuclear Information System (INIS)

    Li Chunguang; Tai Kaixuan

    2011-01-01

    The radioactive contamination of groundwater from in situ leaching (ISL) of uranium mining is a widespread environmental problem. This paper analyzed the monitor results of groundwater contaminations for a in situ leaching uranium mine. A dynamic model of contaminants transport in groundwater in ISL well field was established. The processes and mechanisms of contaminant transport in groundwater were simulated numerically for a ISL well field. A small quantity of U and SO 4 2- migrate to outside of well field during ISL production stage. But the migration velocity and distance of contaminations is small, and the concentration is low. Contaminants migrate as anomalistic tooth-shape. The migration trend of U and SO 4 2- is consistent. Numerical modeling can provide an effective approach to analyse the transport mechanism, and forecast and control the migration of contaminants in groundwater in ISL well field. (authors)

  18. METHODOLOGY TO EVALUATE THE POTENTIAL FOR GROUND WATER CONTAMINATION FROM GEOTHERMAL FLUID RELEASES

    Science.gov (United States)

    This report provides analytical methods and graphical techniques to predict potential ground water contamination from geothermal energy development. Overflows and leaks from ponds, pipe leaks, well blowouts, leaks from well casing, and migration from injection zones can be handle...

  19. Experimental and modelling studies of radionuclide migration from contaminated groundwaters

    International Nuclear Information System (INIS)

    Tompkins, J. A.; Butler, A. P.; Wheater, H. S.; Shaw, G.; Wadey, P.; Bell, J. N. B.

    1994-01-01

    Lysimeter-based studies of radionuclide uptake by winter wheat are being undertaken to investigate soil-to-plant transfer processes. A five year multi-disciplinary research project has concentrated on the upward migration of contaminants from near surface water-tables and their subsequent uptake by a winter wheat crop. A weighted transfer factor approach and a physically based modelling methodology, for the simulation and prediction of radionuclide uptake, have been developed which offer alternatives to the traditional transfer factor approach. Integrated hydrological and solute transport models are used to simulate contaminant movement and subsequent root uptake. This approach enables prediction of radionuclide transport for a wide range of soil, plant and radionuclide types. This paper presents simulated results of 22 Na plant uptake and soil activity profiles, which are verified with respect to lysimeter data. The results demonstrate that a simple modelling approach can describe the variability in radioactivity in both the harvested crop and the soil profile, without recourse to a large number of empirical parameters. The proposed modelling technique should be readily applicable to a range of scales and conditions, since it embodies an understanding of the underlying physical processes of the system. This work constitutes part of an ongoing research programme being undertaken by UK Nirex Ltd., to assess the long term safety of a deep level repository for low and intermediate level nuclear waste. (author)

  20. Monitoring of Water and Contaminant Migration at the Groundwater-Surface Water Interface

    Science.gov (United States)

    2008-08-01

    seepage is occurring in a freshwater lake environment and to map the lateral extent of any subsurface contamination at the groundwater –surface water ...and Contaminant Migration at the Groundwater -Surface Water Interface August 2008 Report Documentation Page Form ApprovedOMB No. 0704-0188 Public...4. TITLE AND SUBTITLE Monitoring of Water and Contaminant Migration at the Groundwater -Surface Water Interface 5a. CONTRACT NUMBER 5b. GRANT NUMBER

  1. Potential Well Water Contaminants and Their Impacts

    Science.gov (United States)

    The first step to protect your health and the health of your family is learning about what may pollute your source of drinking water. Potential contamination may occur naturally, or as a result of human activity.

  2. Geostatistical analysis of prevailing groundwater conditions and potential solute migration at Elstow, Bedfordshire

    International Nuclear Information System (INIS)

    MacKay, R.; Cooper, T.A.; Porter, J.D.; O'Connell, P.E.; Metcalfe, A.V.

    1988-06-01

    A geostatistical approach is applied in a study of the potential migration of contaminants from a hypothetical waste disposal facility near Elstow, Bedfordshire. A deterministic numerical model of groundwater flow in the Kellaways Sands formation and adjacent layers is coupled with geostatistical simulation of the heterogeneous transmissivity field of this principal formation. A particle tracking technique is used to predict the migration pathways for alternative realisations of flow. Alternative statistical descriptions of the spatial structure of the transmissivity field are implemented and the temporal and spatial distributions of escape of contaminants to the biosphere are investigated. (author)

  3. Croatia’s Migration Potential – Micro-Analytic Aspects

    Directory of Open Access Journals (Sweden)

    Saša Božić

    2005-06-01

    Full Text Available The authors set criteria for the selection of a model for measuring migration potential; they select and apply such a model to Croatia and determine the practical and scientific relevance of the Croatian case, especially its significance for the improvement of the chosen model. The authors concentrate on the application of Heinz Fassmann’s and Christiane Hintermann’s micro-analytic model for the estimation of East-Central Europe’s migration potential. After applying this model, they estimate Croatia’s total migration potential at 12.5%, i.e. 460,000 persons older than fourteen. The probable migration potential is estimated at 2.5%, i.e. 92,000 and the real migration potential at 0.4% of the population above fourteen, i.e. 14,700 persons. In Croatian case as well, the younger population (which can still utilise its labour capacity, as well as unemployed, unmarried and highly educated persons, are more likely to consider emigration. The data show also that the regions with the lowest share in GNP have the highest percentage of potential migrants and not the regions which are geographically the closest to potential immigration countries. The authors stress the necessity to integrate migration potential research models. The explanatory assumptions of migration potential research models, based on place utility and subjective expected utility, often overlap when used to interpret the data. Furthermore, the Croatian case shows that personal migration experience and the analytical mezzo level must be considered in order to gain an understanding of the creation of migration preferences.

  4. Contaminants migration in the soil: the influence of transfer between the mobile and stationary phases

    International Nuclear Information System (INIS)

    Moreira, R.M.; Sabino, C.S.V.; Macedo, W.A.

    1996-01-01

    Three transport mechanisms control the contaminant migration in saturated soils: advection, diffusion and interchanges between liquid and solid phases. These interchanges define the retention by the soil and the contaminant delay related to the liquid phase flow. Therefore, the knowledge of the adsorption/desorption characteristics of the solute in solid surfaces is fundamental for the evaluation of toxic agent releases to the compartment soil. This communication reports the study which is being performed by the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN) in this area, particularly with cesium and mercury by using X-ray absorption spectroscopy for contaminants migration

  5. Factors affecting gas migration and contaminant redistribution in heterogeneous porous media subject to electrical resistance heating.

    Science.gov (United States)

    Munholland, Jonah L; Mumford, Kevin G; Kueper, Bernard H

    2016-01-01

    A series of intermediate-scale laboratory experiments were completed in a two-dimensional flow cell to investigate gas production and migration during the application of electrical resistance heating (ERH) for the removal of dense non-aqueous phase liquids (DNAPLs). Experiments consisted of heating water in homogeneous silica sand and heating 270 mL of trichloroethene (TCE) and chloroform (CF) DNAPL pools in heterogeneous silica sands, both under flowing groundwater conditions. Spatial and temporal distributions of temperature were measured using thermocouples and observations of gas production and migration were collected using front-face image capture throughout the experiments. Post-treatment soil samples were collected and analyzed to assess DNAPL removal. Results of experiments performed in homogeneous sand subject to different groundwater flow rates showed that high groundwater velocities can limit subsurface heating rates. In the DNAPL pool experiments, temperatures increased to achieve DNAPL-water co-boiling, creating estimated gas volumes of 131 and 114 L that originated from the TCE and CF pools, respectively. Produced gas migrated vertically, entered a coarse sand lens and subsequently migrated laterally beneath an overlying capillary barrier to outside the heated treatment zone where 31-56% of the original DNAPL condensed back into a DNAPL phase. These findings demonstrate that layered heterogeneity can potentially facilitate the transport of contaminants outside the treatment zone by mobilization and condensation of gas phases during ERH applications. This underscores the need for vapor phase recovery and/or control mechanisms below the water table during application of ERH in heterogeneous porous media during the co-boiling stage, which occurs prior to reaching the boiling point of water. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. West Siberian basin hydrogeology - regional framework for contaminant migration from injected wastes

    International Nuclear Information System (INIS)

    Foley, M.G.

    1994-05-01

    Nuclear fuel cycle activities of the former Soviet Union (FSU) have resulted in massive contamination of the environment in western Siberia. We are developing three-dimensional numerical models of the hydrogeology and potential contaminant migration in the West Siberian Basin. Our long-term goal at Pacific Northwest Laboratory is to help determine future environmental and human impacts given the releases that have occurred to date and the current waste management practices. In FY 1993, our objectives were to (1) refine and implement the hydrogeologic conceptual models of the regional hydrogeology of western Siberia developed in FY 1992 and develop the detailed, spatially registered digital geologic and hydrologic databases to test them, (2) calibrate the computer implementation of the conceptual models developed in FY 1992, and (3) develop general geologic and hydrologic information and preliminary hydrogeologic conceptual models relevant to the more detailed models of contaminated site hydrogeology. Calibration studies of the regional hydrogeologic computer model suggest that most precipitation entering the ground-water system moves in the near-surface part of the system and discharges to surface waters relatively near its point of infiltration. This means that wastes discharged to the surface and near-surface may not be isolated as well as previously thought, since the wastes may be carried to the surface by gradually rising ground waters

  7. The effect of vadose zone heterogeneities on vapor phase migration and aquifer contamination by volatile organics

    Energy Technology Data Exchange (ETDEWEB)

    Seneviratne, A.; Findikakis, A.N. [Bechtel Corporation, San Francisco, CA (United States)

    1995-03-01

    Organic vapors migrating through the vadose zone and inter-phase transfer can contribute to the contamination of larger portions of aquifers than estimated by accounting only for dissolved phase transport through the saturated zone. Proper understanding of vapor phase migration pathways is important for the characterization of the extent of both vadose zone and the saturated zone contamination. The multiphase simulation code T2VOC is used to numerically investigate the effect of heterogeneties on the vapor phase migration of chlorobenzene at a hypothetical site where a vapor extraction system is used to remove contaminants. Different stratigraphies consisting of alternate layers of high and low permeability materials with soil properties representative of gravel, sandy silt and clays are evaluated. The effect of the extent and continuity of low permeability zones on vapor migration is evaluated. Numerical simulations are carried out for different soil properties and different boundary conditions. T2VOC simulations with zones of higher permeability were made to assess the role of how such zones in providing enhanced migration pathways for organic vapors. Similarly, the effect of the degree of saturation of the porous medium on vapor migration was for a range of saturation values. Increased saturation reduces the pore volume of the medium available for vapor diffusion. Stratigraphic units with higher aqueous saturation can retard the vapor phase migration significantly.

  8. A computer model for DNAPL potential migration study

    International Nuclear Information System (INIS)

    Yan, S.; Landry, G.R.; Tate, T.

    1994-01-01

    A computer model, named DNAPMIG (DNAPL Potential Migration), was developed to calculate the dense nonaqueous phase liquid (DNAPL) critical length required to initiate movement and direction of potential migration at locations within an area of interest. The model takes into consideration the potentiometric gradient, bottom structure elevation, DNAPL density, interfacial tension, contact angle, soil grain size, partitioning coefficient, effective solubility, and water saturation. The model is interfaced with SURFER graphics software to use vectors to indicate the DNAPL critical length and the potential migration direction. The potential for DNAPL existence and migration at a specific site can be estimated by relating chemical concentration in the ground water to its solubility limit and the DNAPL critical length. The possibility of vertical migration can also be determined. This model can be used to determine and compare the effectiveness of existing or alternative recovery well systems to capture a DNAPL plume or arrest its movement; to help determine optimum locations and pumping rates of recovery wells; and to help determine the optimum location of environmental borings to locate DNAPL. This paper presents two hypothetical examples and two site applications in south Louisiana

  9. Influence of the Pressure Difference and Door Swing on Heavy Contaminants Migration between Rooms.

    Science.gov (United States)

    Hendiger, Jacek; Chludzińska, Marta; Ziętek, Piotr

    2016-01-01

    This paper presents the results of investigations whose aim was to describe the influence of the pressure difference level on the ability of contaminants migration between neighbouring rooms in dynamic conditions associated with door swing. The analysis was based on airflow visualization made with cold smoke, which simulated the heavy contaminants. The test room was pressurized to a specific level and then the door was opened to observe the trail of the smoke plume in the plane of the door. The door was opened in both directions: to the positively and negatively pressurized room. This study focuses on the visualization of smoke plume discharge and an uncertainty analysis is not applicable. Unlike other studies which focus on the analysis of pressure difference, the present study looks at the contaminants which are heavier than air and on "pumping out" the contaminants by means of door swing. Setting the proper level of pressure difference between the contaminated room and the neighbouring rooms can prove instrumental in ensuring protection against toxic contaminants migration. This study helped to establish the threshold of pressure difference necessary to reduce migration of heavy contaminants to neighbouring rooms.

  10. Software for modelling groundwater transport and contaminant migration

    International Nuclear Information System (INIS)

    Gishkelyuk, I.A.

    2008-01-01

    Facilities of modern software for modeling of groundwater transport and process of contaminant distribution are considered. Advantages of their application are discussed. The comparative analysis of mathematical modeling software of 'Groundwater modeling system' and 'Earth Science Module' from 'COMSOL Multiphysics' is carried out. (authors)

  11. Do Social Casino Gamers Migrate to Online Gambling? An Assessment of Migration Rate and Potential Predictors.

    Science.gov (United States)

    Kim, Hyoun S; Wohl, Michael J A; Salmon, Melissa M; Gupta, Rina; Derevensky, Jeffrey

    2015-12-01

    Social casino games (i.e., free-to-play online gambling games) are enjoyed by millions of players worldwide on a daily basis. Despite being free to play, social casino games share many similarities to traditional casino games. As such, concerns have been raised as to whether social casino games influences the migration to online gambling among people who have not engaged in such activity (see Griffiths in World Online Gambl 9:12-13, 2010). To date, however, no empirical research has assessed this possibility. Thus, the purpose of the present research was to assess the extent to which social casino gamers migrate to online gambling and potential predictors (time spent on social casino games, skill building, enhancement and micro-transactions) of such migration. To this end, social casino gamers who never gambled online (N = 409) completed a questionnaire battery assessing our variables of interest and were re-contacted 6-months later to see if they had engaged in online gambling during the intervening months. Approximately 26% of social casino gamers reported having migrated to online gambling. Importantly, engagement in micro-transactions was the only unique predictor of migration from social casino gaming to online gambling. The implications for the potential harms associated with social casino gaming are discussed.

  12. Field sampling for monitoring migration and defining the areal extent of chemical contamination

    International Nuclear Information System (INIS)

    Thomas, J.M.; Skalski, J.R.; Eberhardt, L.L.; Simmons, M.A.

    1984-11-01

    Initial research on compositing, field designs, and site mapping oriented toward detecting spills and migration at commercial low-level radioactive or chemical waste sites is summarized. Results indicate that the significance test developed to detect samples containing high levels of contamination when they are mixed with several other samples below detectable limits (composites), will be highly effective with large sample sizes when contaminant levels frequently or greatly exceed a maximum acceptable level. These conditions of frequent and high contaminant levels are most likely to occur in regions of a commercial waste site where the priors (previous knowledge) about a spill or migration are highest. Conversely, initial investigations of Bayes sampling strategies suggest that field sampling efforts should be inversely proportional to the priors (expressed as probabilities) for the occurrence of contamination

  13. The peculiarity of the models of the contamination's migration in water in the Chernobyl region

    International Nuclear Information System (INIS)

    Kononovich, A.L.; Krishev, I.I.; Oskolkov, B.Ja.; Kulebakina, L.G.; Arhipov, N.P.

    1997-01-01

    The new factors become significant for Chernobyl's contamination's evolution after 8-10 years. Those factors were hidden in the early 3-5 years. Our paper describes the mathematical model of the migration's process of the radionuclides in Chernobyl cooling pond and some results about the migration of the 137 Cs by groundwater. Our model for radionuclide's migration in the Chernobyl cooling pond differ from other mathematical models, that it takes into account the destruction of the fuel's particles during the time. It shows increased concentration of the 90 Sr in water and the monotonous decrease 137 Cs concentration in water. The results of the model's calculation of the annual concentration of the 137 Cs and 90 Sr in water coincide with measurements results in less than 20%. It is the only model of the Chernobyl cooling pond, which has so good coincidence during 10 years. Result of this work shows that the main process, which determines the time's dependence of the annual concentration of the radionuclides in Chernobyl cooling pond, is the destruction of the fuel's particles. In the second part of the paper there is result of the investigation 137 Cs migration by groundwater. The investigation was made with combination of the physical's modelling and mathematical's modelling methods. Truer is discussion about similarity of the physical-chemical simulation and real process. We had investigated the real Chernobyl's ground's contamination in the physical-chemical's similar model's system. It has observed the fraction of the 137 Cs in groundwater's contamination with very low sorption's coefficient, and thus the big migration's velocity (like 90 Sr). The part of the speed component is about 10 -4 . But the components of 137 Cs contamination, which has the big sorption's coefficient, converts slowly into the 'speed form' during the time. We had no see any publication about 'speed component' of 137 Cs contamination in Chernobyl's groundwater. All contemporary models of

  14. Electrochemical migration in electronics: effect of contamination and bias conditions

    DEFF Research Database (Denmark)

    Verdingovas, Vadimas; Jellesen, Morten Stendahl; Ambat, Rajan

    A number of reliability issues are caused by mechanisms different from the conventional corrosion due to specific aspects of the printed circuit board assembly (PCBA). The size of the components and the distance between them, combinations of dissimilar metals, voltage and temperature gradients...... – all together influence susceptibility of electronic PCBA to corrosion. When electronics is operating under humid conditions, the cleanliness of the PCBA becomes essential, since corrosion related failures in electronics can occur at extremely low levels of moisture and contamination. A synergetic...... effect of the aspects mentioned above makes it challenging to predict the lifetime of electronic device. The aim of this work is to investigate corrosion influencing factors, which at a later stage improve capabilities of predicting the functioning and herewith reliability of electronics under certain...

  15. Modelling of flow and contaminant migration in single rock fractures

    International Nuclear Information System (INIS)

    Dahlblom, P.; Joensson, L.

    1990-03-01

    The report deals with flow and hydrodynamic dispersion of a nonreactive contaminant in a single, irregularly shaped fracture. The main purpose of the report is to describe the basis and development of a computational 'tool' for simulating the aperture geometry of a single fracture and the detailed flow in it. On the basis of this flow information further properties of the fracture can be studied. Some initial application to dispersion of a nonreactive contaminant are thus discussed. The spatial pattern of variation of the fracture aperture is considered as a two-dimensional stochastic process. A method for simulation of such a process is described. The stochastic properties can be chosen arbitrarily. It is assumed that the fracture aperture belongs to a log-normal distribution. For calculation of the flow pattern, the Navier-Stokes equations are simplified to describe low velocity and steady-state flow. These equations, and the continuity equation are integrated in the direction across the fracture plane. A stream function, which describes the integrated flow in the fracture, is defined. A second order partial differential equation, with respect to the stream function, is established and solved by the finite difference method. Isolines for the stream function define boundaries between channels with equal flow rates. The travel time for each channel can be calculated to achieve a measure of the dispersion. The impact of the aperture distribution on the ratio between the mass balance fracture aperture and the cubic law fracture aperture is shown by simple examples. (28 figs., 1 tab., 22 refs.)

  16. Using geographic distribution of well-screen depths and hydrogeologic conditions to identify areas of concern for contaminant migration through inactive supply wells

    Science.gov (United States)

    Gailey, Robert M.

    2018-02-01

    Contaminant migration through inactive supply wells can negatively affect groundwater quality and the combined effects from groups of such wells may cause greater impacts. Because the number of wells in many basins is often large and the geographic areas involved can be vast, approaches are needed to estimate potential impacts and focus limited resources for investigation and corrective measures on the most important areas. One possibility is to evaluate the geographic distribution of well-screen depths relative to hydrogeologic conditions and assess where contaminant migration through wells may be impacting groundwater quality. This approach is demonstrated for a geographically extensive area in the southern Central Valley of California, USA. The conditions that lead to wells acting as conduits for contaminant migration are evaluated and areas where the problem likely occurs are identified. Although only a small fraction of all wells appear to act as conduits, potential impacts may be significant considering needs to control nonpoint-source pollution and improve drinking water quality for rural residents. Addressing a limited number of areas where contaminant migration rates are expected to be high may cost-effectively accomplish the most beneficial groundwater quality protection and improvement. While this work focuses on a specific region, the results indicate that impacts from groups of wells may occur in other areas with similar conditions. Analyses similar to that demonstrated here may guide efficient investigation and corrective action in such areas with benefits occurring for groundwater quality. Potential benefits may justify expenditures to develop the necessary data for performing the analyses.

  17. Prevention of the wind migration of Semipalatinsk test site contaminated topsoil by inter-polymer complexes

    International Nuclear Information System (INIS)

    Kudaibergenov, S.E.

    2010-01-01

    -polymer complexes with formation of ternary polymer-metal complexes. The laboratory experiments demonstrated that the treatment of the topsoil by dilute aqueous solutions of Inter-polymer complexes leads to effective aggregation of the topsoil particles with diameter of 0.01-0.1 mm from 38% (control) to 91%. The average value of wind erosion of aggregated soil becomes less than 1% at the velocity of wind 5 m.s"-"1 in comparison with the value of 74% in case of untreated soil. It was also found that the formed ultrathin crust on the surface of soil particles is able to accumulate the radioactive strontium 4 times higher in comparison with untreated ones. The activity of "2"3"8Pu in the topsoil after treatment by solutions of Inter-polymer complexes increases up to 10000-12000 Bq/kg in comparison with the untreated soil particles (5156 Bq/kg). These results clearly show the potential applicability of Inter-polymer complexes as effective soil remediation materials. The so-called “Koshkar-Ata Lake” located 3 km far from Aktau city and 7-8 km from the Caspian Sea also contains the waste of uranium mining industry. Today the dried area of “Koshkar-Ata Lake” is more than 58 sq. km. In Summer time the thin dust with average diameter 0,01-0,1 mm constantly migrates from the dried part of “Koshkar-Ata Lake” to Aktau city as a result of wind erosion (16-17 m/sec). The developed technology can protect the wind migration of thin dust containing highly toxic heavy metals. It can also be applied to combat against the migration of salted dust from the dried bottom of Aral Sea.

  18. Modeling Contamination Migration on the Chandra X-ray Observatory - II

    Science.gov (United States)

    O'Dell, Stephen L.; Swartz, Douglas A.; Tice, Neil W.; Plucinsky, Paul P.; Grant, Catherine E.; Marshall, Herman L.; Vikhlinin, Alexey A.; Tennant, Allyn F.

    2013-01-01

    During its first 14 years of operation, the cold (about -60C) optical blocking filter of the Advanced CCD Imaging Spectrometer (ACIS), aboard the Chandra X-ray Observatory, has accumulated a growing layer of molecular contamination that attenuates low-energy x rays. Over the past few years, the accumulation rate, spatial distribution, and composition have changed. This evolution has motivated further analysis of contamination migration within and near the ACIS cavity. To this end, the current study employs a higher-fidelity geometric model of the ACIS cavity, detailed thermal modeling based upon temperature data, and a refined model of the molecular transport.

  19. Modelling of contaminant migration in acidic groundwater plumes at uranium tailings impoundments: ADNEUT3

    International Nuclear Information System (INIS)

    Cherry, J.A.; Morin, K.A.; Dubrovsky, N.M.

    1984-06-01

    This report describes the creation and application of ADNEUT3, the latest addition to the ADNEUT (Acid-Drainage NEUTralization) family of computer programs for simulating acid-drainage transport and neutralization. The creation of ADNEUT3 involved the expansion of ADNEUT1 to allow variable input conditions such as changing input solution with time, variable initial amounts of minerals through the simulated streamtube, variable velocities through the streamtube, and variable solubilities for relevant minerals dependent on aqueous chemical composition. Concepts for simulating acid-drainage neutralization are reviewed and ADNEUT3 is then applied to a field-study site of acidic contaminant migration from the Nordic Main uranium-tailings impoundment near Elliot Lake, Ontario. A sensitivity study is first implemented to calibrate ADNEUT3 to the results of the 1979 to 1983 field studies. Then ADNEUT3 is used to define probable past conditions at the site which are not reliably known. In particular, ADNEUT3 is used to help identify: 1) the approximate year when acidic seepage began leaving the tailings impoundment (1966-1967), 2) the past chemical composition of the seepage (somewhat more acidic for a short period of time), and 3) the location of the source area within the tailings for the acidic seepage (near the impoundment dam, close to the field site). Finally, ADNEUT3 is used to predict future contaminant migration. Results indicate that hundreds of years are required under present conditions for the most acidic water with associated high levels of contaminants to migrate about 100 m from the tailings impoundment. The cause of this slow movement is the significant neutralization capacity of the aquifer. If acid production within the tailings decreases in the future, migration rates of contaminants will also decrease

  20. Modeling Contamination Migration on the Chandra X-ray Observatory II

    Science.gov (United States)

    O'Dell, Steve; Swartz, Doug; Tice, Neil; Plucinsky, Paul; Grant, Catherine; Marshall, Herman; Vikhlinin, Alexey

    2013-01-01

    During its first 14 years of operation, the cold (about -60degC) optical blocking filter of the Advanced CCD Imaging Spectrometer (ACIS), aboard the Chandra X-ray Observatory, has accumulated a growing layer of molecular contamination that attenuates low-energy x rays. Over the past few years, the accumulation rate, spatial distribution, and composition may have changed, perhaps partially related to changes in the operating temperature of the ACIS housing. This evolution of the accumulation of the molecular contamination has motivated further analysis of contamination migration on the Chandra X-ray Observatory, particularly within and near the ACIS cavity. To this end, the current study employs a higher-fidelity geometric model of the ACIS cavity, detailed thermal modeling based upon monitored temperature data, and an accordingly refined model of the molecular transport.

  1. DEVELOPMENT OF MIGRATION POTENTIAL IN HUNGARY FROM 2000 UNTIL TODAY

    Directory of Open Access Journals (Sweden)

    Margit Csipkés

    2018-03-01

    Full Text Available Hearing the words “international migration”, two things might come to our mind. One of them is the emigration process and the other is the wave of refugees. In our study, we examined the changes of the number of employees emigrating from Hungary from 2000 until today. Nowadays, the examination of the migration potential is an important topic in Hungary, since the rate of Hungarian emigrants started to grow after 2006 and the rate of growth became even faster after 2010. The reason of the acceleration was the opening of the Austrian and German labour market. The actuality of the topic is based on the fact that international emigration merges the labour market’s processes, influences the given country’s employment level, moreover it has an influencing role on the rate of wages. Emigration from a given state has several reasons: natural disasters, war, marginalization, economic reasons, etc. In our study, we examine emigration caused by economic reasons. We have to take into consideration that measuring emigration processes is a difficult task, due to the lack of data. The reason of the deficiency is that those who leave the country, often forget to report their leaving. From 1 March 2013, only the permanent foreign settlement should be reported towards the administration (District Office, Consulate. Earlier, temporary (more than 3 months settlement was also obligatory to be reported. Many of the leaving Hungarians do not report their leaving, however working abroad for more than 3 months should be reported towards social insurance organizations and tax authorities. I would like to emphasise that my migration potential presentation does not show a direct correlation with the actual migration. However, this study might show the expected movement rates and the composition of emigrants.

  2. Transformers as a potential for soil contamination

    Directory of Open Access Journals (Sweden)

    N. Stojić

    2014-10-01

    Full Text Available The aim of this paper is to investigate the presence of PCBs and heavy metals in the surrounding soil and also in the soil of the receiving pit located below the PCB contaminated transformer. Concentrations of PCBs in our samples are ranged from 0,308 to 0,872 mg/kg of absolutely dry soil.

  3. Inactive supply wells as conduits for flow and contaminant migration: conditions of occurrence and suggestions for management

    Science.gov (United States)

    Gailey, Robert M.

    2017-11-01

    Water supply wells can act as conduits for vertical flow and contaminant migration between water-bearing strata under common hydrogeologic and well construction conditions. While recognized by some for decades, there is little published data on the magnitude of flows and extent of resulting water quality impacts. Consequently, the issue may not be acknowledged widely enough and the need for better management persists. This is especially true for unconsolidated alluvial groundwater basins that are hydrologically stressed by agricultural activities. Theoretical and practical considerations indicate that significant water volumes can migrate vertically through wells. The flow is often downward, with shallow groundwater, usually poorer in quality, migrating through conduit wells to degrade deeper water quality. Field data from locations in California, USA, are presented in combination with modeling results to illustrate both the prevalence of conditions conducive to intraborehole flow and the resulting impacts to water quality. Suggestions for management of planned wells include better enforcement of current regulations and more detailed consideration of hydrogeologic conditions during design and installation. A potentially greater management challenge is presented by the large number of existing wells. Monitoring for evidence of conduit flow and solute transport in areas of high well density is recommended to identify wells that pose greater risks to water quality. Conduit wells that are discovered may be addressed through approaches that include structural modification and changes in operations.

  4. Field sampling for monitoring, migration and defining the areal extent of chemical contamination

    International Nuclear Information System (INIS)

    Thomas, J.M.; Skalski, J.R.; Eberhardt, L.L.; Simmons, M.A.

    1984-01-01

    As part of two studies funded by the U.S. Nuclear Regulatory Commission and the USEPA, the authors have investigated field sampling strategies and compositing as a means of detecting spills or migration at commercial low-level radioactive and chemical waste disposal sites and bioassays for detecting contamination at chemical waste sites. Compositing (pooling samples) for detection is discussed first, followed by the development of a statistical test to determine whether any component of a composite exceeds a prescribed maximum acceptable level. Subsequently, the authors explore the question of optimal field sampling designs and present the features of a microcomputer program designed to show the difficulties in constructing efficient field designs and using compositing schemes. Finally, they propose the use of bioassays as an adjunct or replacement for chemical analysis as a means of detecting and defining the areal extent of chemical migration

  5. Canada Geese at the Hanford Site - Trends in Reproductive Success, Migration Patterns, and Contaminant Concentrations

    International Nuclear Information System (INIS)

    Simmons, Mary Ann; Poston, Ted M.; Tiller, Brett L.; Stegen, Amanda; Hand, Kristine D.; Brandenberger, Jill M.

    2010-01-01

    Pacific Northwest National Laboratory (PNNL) has conducted several studies for the U.S. Department of Energy (DOE) to evaluate the status and condition of Canada geese on the Hanford Reach of the Columbia River. This report summarizes results of studies of Canada geese (Branta canadensis moffitti) at the Hanford Site dating back to the 1950s. Results include information on the nesting (reproductive) success of Canada geese using the Hanford Reach, review of the local and regional migration of this species using data from bird banding studies, and summary data describing monitoring and investigations of the accumulation of Hanford-derived and environmental contaminants by resident goose populations.

  6. Canada Geese at the Hanford Site – Trends in Reproductive Success, Migration Patterns, and Contaminant Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Mary Ann; Poston, Ted M.; Tiller, Brett L.; Stegen, Amanda; Hand, Kristine D.; Brandenberger, Jill M.

    2010-05-25

    Pacific Northwest National Laboratory (PNNL) has conducted several studies for the U.S. Department of Energy (DOE) to evaluate the status and condition of Canada geese on the Hanford Reach of the Columbia River. This report summarizes results of studies of Canada geese (Branta canadensis moffitti) at the Hanford Site dating back to the 1950s. Results include information on the nesting (reproductive) success of Canada geese using the Hanford Reach, review of the local and regional migration of this species using data from bird banding studies, and summary data describing monitoring and investigations of the accumulation of Hanford-derived and environmental contaminants by resident goose populations.

  7. Observations on the migration of bacillus spores outside a contaminated facility during a decontamination efficacy study

    Science.gov (United States)

    Silvestri, Erin E.; Perkins, Sarah; Lordo, Robert; Kovacik, William; Nichols, Tonya L.; Bowling, Charlena Yoder; Griffin, Dale W.; Schaefer, Frank W.

    2015-01-01

    The potential for an intentional wide-area or indoor release of Bacillus anthracis spores remains a concern, but the fate and transport of B. anthracis spores in indoor and outdoor environments are not well understood. Some studies have examined the possibility of spore transport within ventilation systems and in buildings and transport into a building following an outdoor release. Little research exists regarding the potential for spores to migrate to the outside of a building following an indoor release.

  8. Contaminant migration at two low-level radioactive waste sites in arid western United States - a review

    International Nuclear Information System (INIS)

    Wilshire, H.G.; Friedman, I.

    1999-01-01

    Contamination of the unsaturated zone and ground water at the Beatty, Nevada and Richland, Washington low-level radioactive waste sites shows that pathways exist for rapid lateral and vertical migration of contaminants through unconsolidated clastic sediments that comprise the 100 m-thick unsaturated zones of those arid disposal sites. Disposal of liquid wastes at the Beatty site until 1975 may have contributed to rapid migration of contaminants, but negligible amounts of liquid wastes reportedly were disposed at the Richland LLRW site and similar problems of contaminant migration exist. Pathways for vertical migration in the unsaturated zone include fractures and, at Richland, clastic dikes; lateral migration pathways likely are facies-controlled. Disturbance of the disposal sites contributed to increased infiltration of the unlined waste trenches after closure; simulations that used Beatty sample data show dramatic increases in recharge with disturbances necessary to develop the site. Because neither and arid climate nor presence of a thick unsaturated zone offer effective barriers to ground-water contamination, reliance on those factors at proposed sites such as Ward Valley, California and elsewhere is unwarranted. (orig.)

  9. In-situ study of migration and transformation of nitrogen in groundwater based on continuous observations at a contaminated desert site

    Science.gov (United States)

    Zuo, Rui; Jin, Shuhe; Chen, Minhua; Guan, Xin; Wang, Jinsheng; Zhai, Yuanzheng; Teng, Yanguo; Guo, Xueru

    2018-04-01

    The objective of this study was to explore the controlling factors on the migration and transformation of nitrogenous wastes in groundwater using long-term observations from a contaminated site on the southwestern edge of the Tengger Desert in northwestern China. Contamination was caused by wastewater discharge rich in ammonia. Two long-term groundwater monitoring wells (Wells 1# and 2#) were constructed, and 24 water samples were collected. Five key indicators were tested: ammonia, nitrate, nitrite, dissolved oxygen, and manganese. A numerical method was used to simulate the migration process and to determine the migration stage of the main pollutant plume in groundwater. The results showed that at Well 1# the nitrogenous waste migration process had essentially been completed, while at Well 2# ammonia levels were still rising and gradually transitioning to a stable stage. The differences for Well 1# and Well 2# were primarily caused by differences in groundwater flow. The change in ammonia concentration was mainly controlled by the migration of the pollution plume under nitrification in groundwater. The nitrification rate was likely affected by changes in dissolved oxygen and potentially manganese.

  10. Assessment of correlation between leucocytes migration reaction and level of inhalation exposure to priority air contaminants

    Directory of Open Access Journals (Sweden)

    L.B. Masnavieva

    2017-09-01

    Full Text Available Nowadays each forth person suffers from allergic diseases and allergic pathology prevalence is constantly growing. There are compounds in air which are generally toxic, or have sensitizing or allergenic effects on a body. For example, we can name formaldehyde and nitrogen dioxide. Our research goal was to reveal a correlation between reaction of leucocytes migration inhibition to formaldehyde and level of inhalation exposure to the examined chemicals. We examined 410 teenag-ers who permanently lived in industrial cities in Irkutsk region. We studied individual load as per formaldehyde and nitrogen dioxide. We estimated eosinophils content in nasal mucus and determined indexes of leucocytes migration inhibition to for-maldehyde. Index of formaldehyde effects danger was detected to exceed 1 in 54% teenagers. The greatest value of danger coefficient in terms of exposure to this substance was equal to 1.76. anger index in terms of exposure to nitrogen dioxide didn't exceed 0.7 in the examined teenagers. The obtained results prove that inhalation formaldehyde load influences teenag-ers from industrial centers as sensitization to this substance evolves in them. We found out that true inhibition reaction of leucocytes migration in a reaction with formaldehyde more frequently occurred in people with danger index in terms of ex-posure to this substance being lower than 1. We obtained models which described correlation between level of sensitization to formaldehyde and a number of eosinophils in nasal mucus and it allowed us to detect that sensitization depended on the examined contaminants content in the air. The sensitization to chemical air contaminants which we revealed in teenagers calls for necessary activities aimed at reducing risks of allergenic pathology evolvement in them.

  11. Impact of inorganic contaminants on microalgae productivity and bioremediation potential.

    Science.gov (United States)

    Torres, Eric M; Hess, Derek; McNeil, Brian T; Guy, Tessa; Quinn, Jason C

    2017-05-01

    As underdeveloped nations continue to industrialize and world population continues to increase, the need for energy, natural resources, and goods will lead to ever increasing inorganic contaminants, such as heavy metals, in various waste streams that can have damaging effects on plant life, wildlife, and human health. This work is focused on the evaluation of the potential of Nannochloropsis salina to be integrated with contaminated water sources for the concurrent production of a biofuel feedstock while providing an environmental service through bioremediation. Individual contaminants (As, Cd, Cr, Co, Cu, Pb, Ni, Hg, Se, and Zn) at various concentrations ranging from a low concentration (1X) to higher concentrations (10X, and 40X) found in contaminated systems (mine tailings, wastewater treatment plants, produced water) were introduced into growth media. Biological growth experimentation was performed in triplicate at the various contaminant concentrations and at 3 different light intensities. Results show that baseline concentrations of each contaminant slightly decreased biomass growth to between 89% and 99% of the control with the exception of Ni which dramatically reduced growth. Increased contaminant concentrations resulted in progressively lower growth rates for all contaminants tested. Lipid analysis shows most baseline contaminant concentrations slightly decrease or have minimal effects on lipid content at all light levels. Trace contaminant analysis on the biomass showed Cd, Co, Cu, Pb, and Zn were sorbed by the microalgae with minimal contaminants remaining in the growth media illustrating the effectiveness of microalgae to bioremediate these contaminants when levels are sufficiently low to not detrimentally impact productivity. The microalgae biomass was less efficient at sorption of As, Cr, Ni, and Se. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Migration and Its Effects on Agriculture and Rural Development Potential.

    Science.gov (United States)

    Bird, Alan R.

    Migration is a major continuing phenomenon associated with national and subnational development. The past, present, and future significance of migration on rural development and agriculture are reviewed in this paper. Data are cited which appear to be at variance with popular beliefs. The complexity of interrelationships between migration…

  13. Case study: Managing potentially contaminated records

    International Nuclear Information System (INIS)

    Sprouse, B.S.

    1993-06-01

    For the past 10 or more years, Analytical Laboratory data cards have been generated and stored in the 222-S Laboratory at the Hanford Site in Richland, Washington. These cards are classified as record material and require retention for a minimum of 75 years in an approved storage facility in accordance with Westinghouse Hanford Company procedures. The cards are maintained in records boxes in the attic of the 222-S Laboratory and are subject to potential risk and loss. The most significant potential risks are radiological hazards. Various options are available for removal, cataloging, transmittal, and storage of these long-term records. Because the records are currently stored in a radiation protection zone, they surveyed before being released from the facility. This survey can be arduous and time consuming. Resolutions to the problem of removal and proper storage of the records from the facility need to be addressed. The records were reviewed and inventoried to determine the quantity of information. A study of the various options available was conducted, and based on the information collected, it was determined that the most feasible and cost-effective approach is to microfilm the cards inside the laboratory. This option complies with all applicable company requirements and decreases the estimated radiological survey time from approximately 3.5 years to under 40 hours. This activity will result in a potential savings of $350,000 over the life of the activity

  14. Application of MOGRA for migration of contaminants through different land utilization areas

    International Nuclear Information System (INIS)

    Amano, Hikaru; Uchida, Shigeo; Matsuoka, Syungo; Ikeda, Hiroshi; Hayashi, Hiroko; Kurosawa, Naohiro

    2003-01-01

    The functionality of MOGRA is being verified by applying it in the analyses of the migration rates of radioactive substances from the atmosphere to soils and plants and flow rates into the rivers. This has been achieved by also taking their mode classifications into consideration. In this report, a hypothetical combination of land usage was supposed to check the function of MOGRA. The land usage was consisted from cultivated lands, forests, uncultivated lands, urban area, river, and lake. Each land usage has its own inside model which is basic module. Also supposed was homogeneous contamination of the surface land from atmospheric deposition of Cs-137 (1.0 Bq/m 2 ). The system can analyze the dynamic changes of Cs-137 concentrations in each compartment, fluxes from one compartment to another compartment. (author)

  15. Influence of the tension-saturated zone on contaminant migration in shallow water-table regimes

    International Nuclear Information System (INIS)

    Gillham, R.W.

    1982-01-01

    Groundwater discharge represents a major pathway for the return to the biosphere of contaminants that are released to the subsurface environment. An understanding of the transport processes in groundwater discharge zones is therefore an important consideration in pathway analyses associated with the environmental assessment of proposed waste-management facilities. Shallow water tables are a common characteristic of groundwater discharge zones, particularly in humid climatic regions. In this paper, the results of field tests, laboratory tests and numerical simulations are used to show that under shallow water-table conditions, the zone of tension saturation can result in a rapid and highly disproportionate water-table response to precipitation. It is further shown that this response can result in complex migration patterns that would not be predicted by the classical approaches to solute transport modelling and that the response could result in large and highly transient inputs to surface water

  16. Estimates of potential radionuclide migration at the Bullion site

    International Nuclear Information System (INIS)

    Brikowski, T.H.

    1992-04-01

    The Bullion site in Area 20 of the Nevada Test Site has been selected for an intensive study of the hydrologic consequences of underground testing, including subsequent radionuclide migration. The bulk of the chimney and cavity lie in zeolitized tuffs of low hydraulic conductivity, while the base of the cavity may extend downward into more conductive rhyolite flows. A mathematical analog to the Bullion setting is used here to estimate expected radionuclide migration rates and concentrations. Because of a lack of hydrologic data at the site, two contrasting scenarios are considered. The first is downward-transport, in which downward hydraulic gradients flush chimney contents into the conductive underlying units, enhancing migration. The other is upward-transport, in which upward gradients tend to drive chimney contents into the low-conductivity zeolitized tuffs, discouraging migration. In the downward-transport scenario, radionuclide travel times and concentrations are predicted to be similar to those encountered at Cheshire, requiring approximately 10 years to reach a proposed well 300 m downgradient. The upward transport scenario yields predicted travel times on the order of 2,000 years to the downgradient well. The most likely scenario is a combination of these results, with vertical movement playing a limited role. Radionuclides injected directly into the rhyolites should migrate laterally very quickly, with travel times as in the downward-transport scenario. Those in the zeolitized tuff-walled portion of the chimney should migrate extremely slowly, as in the upward-transport scenario

  17. Modeling potential migration of petroleum hydrocarbons from a mixed-waste disposal site in the vadose zone

    International Nuclear Information System (INIS)

    Rawson, S.A.; Walton, J.C.; Baca, R.G.

    1989-01-01

    Environmental monitoring of a mixed-waste disposal site at the Idaho National Engineering Laboratory has confirmed release and migration into the vadose zone of: (1) chlorinated hydrocarbons in the vapor phase and (2) trace levels of certain transuranic elements. The finding has prompted an evaluation of the potential role of waste petroleum hydrocarbons in mediating or influencing contaminant migration from the disposal site. Disposal records indicate that a large volume of machine oil contaminated with transuranic isotopes was disposed at the site along with the chlorinated solvents and other radioactive wastes. A multiphase flow model was used to assess the possible extent of oil and vapor movement through the 177 m thick vadose zone. One dimensional simulations were performed to estimate the vertical distribution of the vapor phase, the aqueous phase, and immiscible free liquid as a function of time. The simulations indicate that the oil may migrate slowly through the vadose zone, to potentially significant depths. Calculated transport rates support the following ranking with regard to relative mobility: vapor phase > aqueous phase > free liquid. 21 refs., 7 figs., 2 tabs

  18. The potential migration effect of rural hospital closures

    DEFF Research Database (Denmark)

    Sørensen, Jens Fyhn Lykke

    2008-01-01

    to out-migration, although the hypothetical way of questioning leaves uncertainty about the actual scale of out-migration. Child families appear to be the most likely out-migrants. Elderly people may be hardest hit by a hospital closure, being most reliant on health care and least inclined to move away.......Rural hospital closures are high on the current health care agenda in Denmark. One raised concern is that rural hospital closures may further decrease population numbers in rural areas, as closures may induce some residents to move away from affected areas, i.e. closer to health care services...

  19. Environmental migration of radium and other contaminants present in liquid and solid wastes from the mining and milling of uranium

    International Nuclear Information System (INIS)

    1986-04-01

    This coordinated research programme has been directed at studying the migration of radium and other contaminants from tailings. It is therefore particularly concerned with the migration and transfer processes caused by ingress of water into tailings piles. Some of the studies in the programme have been concerned with the behaviour of radium after transfer into aquatic systems while others were concerned with the basic processes which occur in tailings piles. Studies of the latter type are essential if the long-term behaviour of radium and other contaminants is to be predicted with confidence and the effects of various treatment schemes are to be understood. The migration behaviour of radium-226, as a precursor to radon-222, will also have an effect on the long-term emission of this gas. The appendices of this report contain the guidance on analysis and measurement procedures and the summaries of research carried out by individual contractors

  20. Printed paper and board food contact materials as a potential source of food contamination.

    Science.gov (United States)

    Van Bossuyt, Melissa; Van Hoeck, Els; Vanhaecke, Tamara; Rogiers, Vera; Mertens, Birgit

    2016-11-01

    Food contact materials (FCM) are estimated to be the largest source of food contamination. Apart from plastics, the most commonly used FCM are made of printed paper and board. Unlike their plastic counterparts, these are not covered by a specific European regulation. Several contamination issues have raised concerns towards potential adverse health effects caused by exposure to substances migrating from printed paper and board FCM. In the current study, an inventory combining the substances which may be used in printed paper and board FCM, was created. More than 6000 unique compounds were identified, the majority (77%) considered non-evaluated in terms of potential toxicity. Based on a preliminary study of their physicochemical properties, it is estimated that most of the non-evaluated single substances have the potential to migrate into the food and become bioavailable after oral intake. Almost all are included in the FACET tool, indicating that their use in primary food packaging has been confirmed by industry. Importantly, 19 substances are also present in one of the lists with substances of concern compiled by the European Chemicals Agency (ECHA). To ensure consumer safety, the actual use of these substances in printed paper and board FCM should be investigated urgently. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Potential contamination of groundwater in the World Heritage Site of ...

    African Journals Online (AJOL)

    The rapid population growth, high levels of tourism and poor sewage waste disposal (at least for the foreseeable future) in St. Katherine have resulted in potential contamination of groundwater and subsequent high risk to human health. To evaluate the safety of well water for human use in St. Katherine, water samples were ...

  2. Challenges in the Management of Potentially Contaminated Scrap Metal

    Energy Technology Data Exchange (ETDEWEB)

    Meehan, R.W., E-mail: meehanrw@em.doe.gov [US Department of Energy, National Nuclear Security Administration, Washington, DC (United States)

    2011-07-15

    This paper describes the background and current status of the management of potentially contaminated metals and materials at the US Department of Energy (DOE) sites across the USA. The current DOE policy prohibiting the release of metal scrap for recycling from radiation areas is explained. Finally, a potential path forward to competently assess, characterize and clear material from radiological control is proposed that uses a combination of administrative processes and empirical techniques that are valid irrespective of the standard used for clearance. (author)

  3. Monitoring Potential Transport of Radioactive Contaminants in Shallow Ephemeral Channels

    International Nuclear Information System (INIS)

    Miller Julianne J.; Mizell Steve A.; Nikolich George; Campbell Scott A.

    2012-01-01

    The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA), Nevada Site Office (NSO), Environmental Restoration Soils Activity has authorized the Desert Research Institute (DRI) to conduct field assessments of potential sediment transport of contaminated soil from Corrective Action Unit (CAU) 550, Area 8 Smoky Contamination Area (CA), during precipitation runoff events. CAU 550 includes Corrective Action Sites (CASs) 08-23-03, 08-23-04, 08-23-06, and 08-23-07; these CASs are associated with tests designated Ceres, Smoky, Oberon, and Titania, respectively.

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

    Science.gov (United States)

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

  5. Use of Unicellular Algae for Evaluation of Potential Aquatic Contaminants

    Science.gov (United States)

    1981-05-01

    well as long term effects on specific water bodies such as lakes and groundwater basins. Both the hydrazine propellants and the alternative jet fuels... freshwater bioassays was S. capricornutum. Initial investigations of marine waters used Dunaliella tertiolecta as the test organism but the differences in...AFAMRL-TR-80-85 USE OF UNICELLUAR ALGAE FOR EVALUATION OF POTENTIAL AQUATIC CONTAMINANTS JAN SCHERFIG PETER S. DIXON CAROL A. JUSTICE ALBERTO ACEVEDO

  6. HTO as a conservative tracer used for characterization of contaminant migration in porous rock environment

    International Nuclear Information System (INIS)

    Havlova, V.; Vopalka, D.

    2010-01-01

    Methodology for diffusion coefficient determination was applied on sandstone samples, using conservative non sorbing tracer. The results proved that methodology, through-diffusion cell design and GoldSim diffusion module can be used for sandstone samples in order to determine important migration parameters, necessary for transport model input. However, rock heterogeneity factor has to be taken into account in any case as it can potentially change rock properties, even within centimeter scale. Effective diffusion coefficient D e for rock samples was determined. The values fell into the range of 1.0-6.17 x 10 -10 m 2 s -1 . Discrepancies in measured and simulated porosity were observed. Statistical analyses revealed that values of diffusion coefficient D e were in close interrelation to primary mineral (quartz) and cement forming minerals (kaolinite and organic matter). (author)

  7. Microorganisms as potential vectors of the migration of radionuclides?

    International Nuclear Information System (INIS)

    Yves, A.

    1998-01-01

    The aims of our work are the study of the sorption of radionuclides by bacteria as the first step in the microorganism-metal interaction. The latter involves the fixation of ions on a surface layer and it results in the immobilization of the metal, thus possibly being the primary step of bioaccumulation. After a rapid presentation of the direct and indirect mechanisms of the interactions, we shall present our experiments of radionuclide biosorption by bacteria. A salient feature of biosorption is the selectivity of the adsorption of some radionuclides from a composed solution. For example, Andres et al. (1993, 1995) have shown that Mycobacterium smegmatis, from a composed solution containing uranium, thorium, lanthanum, europium and ytterbium, selectively adsorbs thorium ions. The sequence of preferential fixation is: Th 4+ > UO 2 2+ > La 3+ = Eu 3+ = Yb 3+ . This selectivity is a function of the cell wall organization and of the speciation of the metal in the solution. Yet, each species of bacteria has characteristic and specific cell wall layer composition and organization. Moreover, the culture and the environmental conditions change the surface layer properties. Another parameter in the migration of radionuclides is the transfer from the soil to the microorganisms. In column experiments, Gd, and likely the rare earths, in general, adsorbed on sand can be removed with a suspension of bacteria (Thouand and Andres 1997). These examples will be discussed and serve as a basis to illustrate the diversity of the interactions between microorganisms and radionuclides

  8. Coastal wetland adaptation to sea level rise: Quantifying potential for landward migration and coastal squeeze

    Science.gov (United States)

    Borchert, Sinéad M.; Osland, Michael J.; Enwright, Nicholas M.; Griffith, Kereen

    2018-01-01

    Coastal wetland ecosystems are expected to migrate landwards in response to rising seas. However, due to differences in topography and coastal urbanization, estuaries vary in their ability to accommodate migration. Low‐lying urban areas can constrain migration and lead to wetland loss (i.e. coastal squeeze), especially where existing wetlands cannot keep pace with rising seas via vertical adjustments. In many estuaries, there is a pressing need to identify landward migration corridors and better quantify the potential for landward migration and coastal squeeze.We quantified and compared the area available for landward migration of tidal saline wetlands and the area where urban development is expected to prevent migration for 39 estuaries along the wetland‐rich USA Gulf of Mexico coast. We did so under three sea level rise scenarios (0.5, 1.0, and 1.5 m by 2100).Within the region, the potential for wetland migration is highest within certain estuaries in Louisiana and southern Florida (e.g. Atchafalaya/Vermilion Bays, Mermentau River, Barataria Bay, and the North and South Ten Thousand Islands estuaries).The potential for coastal squeeze is highest in estuaries containing major metropolitan areas that extend into low‐lying lands. The Charlotte Harbor, Tampa Bay, and Crystal‐Pithlachascotee estuaries (Florida) have the highest amounts of urban land expected to constrain wetland migration. Urban barriers to migration are also high in the Galveston Bay (Texas) and Atchafalaya/Vermilion Bays (Louisiana) estuaries.Synthesis and applications. Coastal wetlands provide many ecosystem services that benefit human health and well‐being, including shoreline protection and fish and wildlife habitat. As the rate of sea level rise accelerates in response to climate change, coastal wetland resources could be lost in areas that lack space for landward migration. Migration corridors are particularly important in highly urbanized estuaries where, due to low‐lying coastal

  9. Electro-migration of heavy metals in an aged electroplating contaminated soil affected by the coexisting hexavalent chromium.

    Science.gov (United States)

    Zhang, Weihua; Zhuang, Luwen; Tong, Lizhi; Lo, Irene M C; Qiu, Rongliang

    2012-02-01

    Cr(VI) was often reported to oxidize soil organic matter at acidic environments due to its high ORP, probably thus changing cationic metal species bound to soil organic matter, and influencing their electro-migration patterns. However, such an effect on the electro-migration was not confirmed in most previous studies. Therefore, this study applied a fixed voltage direct current field on an aged electroplating contaminated clayed soil, with a special interest in the direct or indirect influence of Cr(VI) on the electro-migration of other coexisting metals. After 353 h electrokinetic process, 81% of Zn, 53% of Ni and 22% of Cu in the original soil were electro-migrated into the electrolyte, and most of the remaining concentrated near the cathode. The Cr(VI) oxidized some soil organic matter along its migration pathway, with a pronounced reaction occurred near the anode at low pHs. The resulting Cr(III) reversed its original movement, and migrated towards the cathode, leading to the occurrence of a second Cr concentration peak in the soil. Metal species analyses showed that the amount of metals bound to soil organic matter significantly decreased, while a substantial increase in the Cr species bound to Fe/Mn (hydro-)oxides was observed, suggesting an enhancement of cationic metal electro-migration by the reduction of Cr(VI) into Cr(III). However, the Cr(VI) may form some stable lead chromate precipitates, and in turn demobilize Pb in the soil, as the results showed a low Pb removal and an increase in its acid-extractable and residual fractions after electrokinetic remediation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Characterisation and potential migration of silver nanoparticles from commercially available polymeric food contact materials.

    Science.gov (United States)

    Addo Ntim, Susana; Thomas, Treye A; Begley, Timothy H; Noonan, Gregory O

    2015-01-01

    The potential for consumer exposure to nano-components in food contact materials (FCMs) is dependent on the migration of nanomaterials into food. Therefore, characterising the physico-chemical properties and potential for migration of constituents is an important step in assessing the safety of FCMs. A number of commercially available food storage products, purchased domestically within the United States and internationally, that claim to contain nanosilver were evaluated. The products were made of polyethylene, polypropylene and polyphenylene ether sulfone and all contained silver (0.001-36 mg kg(-1) of polymer). Silver migration was measured under various conditions, including using 3% acetic acid and water as food simulants. Low concentrations (sub-ppb levels) of silver were detected in the migration studies generally following a trend characterised by a surface desorption phenomenon, where the majority of the silver migration occurred in the first of three consecutive exposures. Silver nanoparticles were not detected in food simulants, suggesting that the silver migration may be due solely to ionic silver released into solution from oxidation of the silver nanoparticle surface. The absence of detectable silver nanoparticles was consistent with expectations from a physico-chemical view point. For the products tested, current USFDA guidance for evaluating migration from FCMs was applicable.

  11. Bioaccumulation of radionuclides and metals by microorganisms: Potential role in the separation of inorganic contaminants and for the in situ treatment of the subsurface

    International Nuclear Information System (INIS)

    Bolton, H. Jr.; Wildung, R.E.

    1993-01-01

    Radionuclide, metal and organic contaminants are present in relatively inaccessible subsurface environments at many U.S Department of Energy (DOE) sites. Subsurface contamination is of concern to DOE because the migration of these contaminants into relatively deep subsurface zones indicates that they exist in a mobile chemical form and thus could potentially enter domestic groundwater supplies. Currently, economic approaches to stabilize or remediate these deep contaminated zones are limited, because these systems are not well characterized and there is a lack of understanding of how geochemical, microbial, and hydrological processes interact to influence contaminant behavior. Microorganisms offer a potential means for radionuclide and metal immobilization or mobilization for subsequent surface treatment. Bioaccumulation is a specific microbial sequestering mechanism wherein mobile radionuclides and metals become associated with the microbial biomass by both intra- and extracellular sequestering ligands. Since most of the microorganism in the subsurface are associated with the stationary strata, bioaccumulation of mobile radionuclides and metals would initially result in a decrease in the transport of inorganic contaminants. How long the inorganic contaminants would remain immobilized, the selectivity of the bioaccumulation process for specific inorganic contaminants, the mechanism involved, and how the geochemistry and growth conditions of the subsurface environment influence bioaccumulation are not currently known. This presentation focuses on the microbial process of immobilizing radionuclides and metals and using this process to reduce inorganic contaminant migration at DOE sites. Background research with near-surface microorganisms will be presented to demonstrate this process and show its potential to reduce inorganic contaminant migration. Future research needs and approaches in this relatively new research area will also be discussed

  12. A radiotracer technique for the migration of inorganic contaminants into dry food from packaging made from recycled paper and board

    International Nuclear Information System (INIS)

    Aston, D.S.J.; Parry, S.J.

    2005-01-01

    A radiotracer method, initially developed to analyze migration from retail plastic food packaging into food simulants, has been developed to assess the measurement of inorganic contaminants migrating from recycled paper and board into real food. This new radiotracer method has been applied to the study of 10 food samples and their corresponding recycled paper and board packaging. Samples of paper and board were irradiated in a thermal neutron flux of 1.26 x 10 16 n x m -2 x s -1 for 15 hours to activate elements of interest. After a decay period of 10 days the paper and board was placed in contact with the corresponding foodstuff. The food was analyzed for any radioactivity migrating from the packaging by gamma-ray spectrometry. Samples were analyzed regularly during the 90 days contact time. Detection limits for the determination of migration was as low as a few μg/kg in the food. Results from the migration study have shown that, of the 60 elements measured, only Zn and Fe were detected in food, at concentrations of 0.012-0.25, and 0.045-0.11 mg/kg, respectively. This was despite the recycled paper and board samples being highly elevated in many other elements such as Cr (0.9-15.1 mg/kg) and Ba (3.3-75.4 mg/kg). The level of migration of Zn and Fe into food from packaging was insignificant compared to the UK recommended daily allowances of 15 mg, and, therefore, represented no hazard to human health. (author)

  13. Long term contaminant migration and impacts from uranium mill tailings. Comparison of computer models using a hypothetical dataset

    International Nuclear Information System (INIS)

    Camus, H.

    1995-11-01

    and not to represent realistic releases. As such, the results presented do not reflect the actual impact of any real facility. While absolute conclusions about critical pathways etc should not be drawn, a number of useful indicative observations can be made arising from the results comparisons. The V1.07 exercise is essentially a simplified but comprehensive performance assessment of a hypothetical waste disposal facility. The range of results provided using a variety of modelling approaches and models in differing stages of development suggests that it is difficult to exclude from consideration particular contaminants or migration and exposure pathways in advance of detailed assumptions for source terms and other site and assessment specific features. This is consistent with results from an earlier, more generic, BIOMOVS multiple pathway study. Peak impacts on individuals from uranium mill tailings, may not arise for many hundreds of years. Since during this period many possible site and environmental changes might occur, not least because of human actions, a Reference Biosphere approach may be appropriate in developing the scenarios to be modelled for a real site. Reference Biospheres for solid waste disposal assessments are under discussion elsewhere within the BIOMOVS II programme. Methods are available for assessing radiological and non-radiological health risks to individuals from releases from tailings facilities, though their relative significance will be locally dependent. Simplifications to modelling of contaminant accumulation in soil (eg using a 100 year residence time for all contaminants) are probably inappropriate. The long term accumulation potential of the different contaminants may be substantially different. It follows that assumptions have to be made about soil structure and use over the long term. Simplification of the U-238 decay chain, i e assuming Pb-210 and Po-210 are in secular equilibrium with the long-lived parent, Ra-226, is probably not

  14. Long term contaminant migration and impacts from uranium mill tailings. Comparison of computer models using a hypothetical dataset

    Energy Technology Data Exchange (ETDEWEB)

    Camus, H [CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses (France). Inst. de Protection et de Surete Nucleaire; and others

    1995-11-01

    and not to represent realistic releases. As such, the results presented do not reflect the actual impact of any real facility. While absolute conclusions about critical pathways etc should not be drawn, a number of useful indicative observations can be made arising from the results comparisons. The V1.07 exercise is essentially a simplified but comprehensive performance assessment of a hypothetical waste disposal facility. The range of results provided using a variety of modelling approaches and models in differing stages of development suggests that it is difficult to exclude from consideration particular contaminants or migration and exposure pathways in advance of detailed assumptions for source terms and other site and assessment specific features. This is consistent with results from an earlier, more generic, BIOMOVS multiple pathway study. Peak impacts on individuals from uranium mill tailings, may not arise for many hundreds of years. Since during this period many possible site and environmental changes might occur, not least because of human actions, a Reference Biosphere approach may be appropriate in developing the scenarios to be modelled for a real site. Reference Biospheres for solid waste disposal assessments are under discussion elsewhere within the BIOMOVS II programme. Methods are available for assessing radiological and non-radiological health risks to individuals from releases from tailings facilities, though their relative significance will be locally dependent. Simplifications to modelling of contaminant accumulation in soil (eg using a 100 year residence time for all contaminants) are probably inappropriate. The long term accumulation potential of the different contaminants may be substantially different. It follows that assumptions have to be made about soil structure and use over the long term. Simplification of the U-238 decay chain, i e assuming Pb-210 and Po-210 are in secular equilibrium with the long-lived parent, Ra-226, is probably not

  15. Onsite disposal of radioactive waste: Estimating potential groundwater contamination

    International Nuclear Information System (INIS)

    Goode, D.J.; Neuder, S.M.; Pennifill, R.A.; Ginn, T.

    1986-11-01

    Volumes 1 and 2 of this report describe the NRC's methodology for assessing the potential public health and environmental impacts associated with onsite disposal of very low activity radioactive materials. This volume (Vol. 3) describes a general methodology for predicting potential groundwater contamination from onsite disposal. The methodology includes formulating a conceptual model, representing the conceptual model mathematically, estimating conservative parameters, and predicting receptor concentrations. Processes which must generally be considered in the methodology include infiltration, leaching of radionuclides from the waste, transport to the saturated zone, transport within the saturated zone, and withdrawal at a receptor location. A case study of shallow burial of iodine-125 illustrates application of the MOCMOD84 version of the US Geological Survey's 2-D solute transport model and a corresponding analytical solution. The appendices include a description and listing of MOCMOD84, descriptions of several analytical solution techniques, and a procedure for estimating conservative groundwater velocity values

  16. Biogeochemical cycles of Chernobyl-born radionuclides in the contaminated forest ecosystems: long-term dynamics of the migration processes

    Science.gov (United States)

    Shcheglov, Alexey; Tsvetnova, Ol'ga; Klyashtorin, Alexey

    2013-04-01

    Biogeochemical migration is a dominant factor of the radionuclide transport through the biosphere. In the early XX century, V.I. Vernadskii, a Russian scientist known, noted about a special role living things play in transport and accumulation of natural radionuclide in various environments. The role of biogeochemical processes in migration and redistribution of technogenic radionuclides is not less important. In Russia, V. M. Klechkovskii and N.V. Timofeev-Ressovskii showed some important biogeochemical aspects of radionuclide migration by the example of global fallout and Kyshtym accident. Their followers, R.M. Alexakhin, M.A. Naryshkin, N.V. Kulikov, F.A. Tikhomirov, E.B. Tyuryukanova, and others also contributed a lot to biogeochemistry of radionuclides. In the post-Chernobyl period, this area of knowledge received a lot of data that allowed building the radioactive element balance and flux estimation in various biogeochemical cycles [Shcheglov et al., 1999]. Regrettably, many of recent radioecological studies are only focused on specific radionuclide fluxes or pursue some applied tasks, missing the holistic approach. Most of the studies consider biogeochemical fluxes of radioactive isotopes in terms of either dose estimation or radionuclide migration rates in various food chains. However, to get a comprehensive picture and develop a reliable forecast of environmental, ecological, and social consequences of radioactive pollution in a vast contaminated area, it is necessary to investigate all the radionuclide fluxes associated with the biogeochemical cycles in affected ecosystems. We believe such an integrated approach would be useful to study long-term environmental consequences of the Fukushima accident as well. In our long-term research, we tried to characterize the flux dynamics of the Chernobyl-born radionuclides in the contaminated forest ecosystems and landscapes as a part of the integrated biogeochemical process. Our field studies were started in June of

  17. The potentially neglected culprit of DC surface flashover: electron migration under temperature gradients.

    Science.gov (United States)

    Li, Chuanyang; Hu, Jun; Lin, Chuanjie; He, Jinliang

    2017-06-12

    This report intends to reveal the role of electron migration and its effects in triggering direct current (DC) surface flashover under temperature gradient conditions when using epoxy-based insulating composites. The surface potential and the surface flashover voltage are both measured using insulators that are bridged between two thermo-regulated electrodes. The space charge injection and migration properties under different temperature are detected. The results show that the surface potential rises significantly because of electron migration near the high voltage (HV) electrode under high temperature conditions, thus creating an "analogous ineffective region". The expansion of this "analogous ineffective region" results in most of the voltage drop occurring near the ground electrode, which serves as an important factor triggering positive streamers across the insulation surface. This work is helpful in understanding of DC surface flashover mechanism from a new perspective and also has important significance in design of a suitable DC insulator to avoid surface flashover problem.

  18. Fungal Peptaibiotics: Assessing Potential Meteoritic Amino Acid Contamination

    Science.gov (United States)

    Elsila, J. E.; Callahan, M. P.; Glavin, D. P.; Dworkin, J. P.; Bruckner, H.

    2010-01-01

    The presence of non-protein alpha-dialkyl-amino acids such as alpha-aminoisobutyric acid (alpha-A1B) and isovaline (Iva), which are relatively rare in the terrestrial biosphere, has long been used as an indication of the indigeneity of meteoritic amino acids, however, the discovery of alpha-AIB in peptides producers by a widespread group of filamentous fungi indicates the possibility of a terrestrial biotic source for the alpha-AIB observed in some meteorites. The alpha-AIB-containing peptides produced by these fungi are dubbed peptaibiotics. We measured the molecular distribution and stable carbon and nitrogen isotopic ratios for amino acids found in the total hydrolysates of four biologically synthesized peptaibiotics. We compared these aneasurenetts with those from the CM2 carbonaceous chondrite Murchison and from three Antarctic CR2 carbonaceous chondrites in order to understand the peptaibiotics as a potential source of meteoritic contamination.

  19. Potential directions of the 'town-to-town' migration in Vojvodina

    Directory of Open Access Journals (Sweden)

    Savić Mirko

    2008-01-01

    Full Text Available Population of Vojvodina is showing the characteristics of late demographic transition. The main characteristics of that phase are low mortality rate, slow decrease of fertility rate, increased number of older people etc. This phase is connected to fourth development phase of migrations with significant migrations from one city to another and inside the city area. The purpose of this paper is to define the basic characteristics of potential internal migrations in the region of Vojvodina between cities, most of all towards Novi Sad as economic, political and cultural center. The sample of 2.000 respondents was formed and survey was conducted in the 15 largest cities in the region. The data were analyzed with methods of descriptive and multivariate statistical analysis (rank correlation and MDS analysis. Basic conclusions are that theory of transitional migration is confirmed in Vojvodina, the size of the city is not the only factor for potential migration movements and Novi Sad is by far the most desired destination for significant portion of population in the region, especially of population aged between 20 and 40 years because around 40% of that cohort wish to move to Novi Sad. That will cause significant urban, economic and social problems, not only in the city of Novi Sad but also in the cities where immigrants are coming from. .

  20. Schistosoma mansoni: migration potential of normal and radiation attenuated parasites in naive guinea pigs

    International Nuclear Information System (INIS)

    Kamiya, H.; McLaren, D.J.

    1987-01-01

    Compressed tissue autoradiography using [75Se]selenomethionine labelled parasites has been used to investigate the migration potential of normal and radiation attenuated cercariae of Schistosoma mansoni in naive guinea pigs. By Day 14 after infection. 44% of normal parasites were detected as reduced silver foci in the liver; this value corresponded well with the number of liver parasites recovered by retrograde perfusion of the hepatic portal system on Day 42 (42% of the challenge). In contrast, cercariae subjected to 50 krad of gamma irradiation failed to migrate out of the skin. The migration capacity of 20 krad irradiated parasites was less severely affected in that about half of the challenge parasites reached the lungs, but virtually none moved to the liver. These data are discussed in relation to the kinetics of immunity induced in guinea pigs by infection or vaccination with normal or radiation attenuated parasites

  1. Review of the potential effects of alkaline plume migration from a cementitious repository for radioactive waste

    International Nuclear Information System (INIS)

    Savage, D.

    1997-01-01

    Extensive use of cement and concrete is envisaged in the construction of geological repositories for low and intermediate-level radioactive wastes, both for structural, and encapsulation and backfilling purposes. Saturation of these materials with groundwater may occur in the post-closure period of disposal, producing a hyperalkaline pore fluid with a pH in the range 10-13.5. These pore fluids have the potential to migrate from the repository according to local groundwater flow conditions and react chemically with the host rock. These chemical reactions may affect the rock's capacity to retard the migration of radionuclides released from the repository after the degradation of the waste packages. The effects of these chemical reactions on the behaviour of the repository rock as a barrier to waste migration need to be investigated for the purposes of assessing the safety of the repository design (so-called 'safety assessment' or 'performance assessment'). The objectives of the work reported here were to: identify those processes influencing radionuclide mobility in the geosphere which could be affected by plume migration; review literature relevant to alkali-rock reaction; contact organisations carrying out relevant research and summarise their current and future activities; and make recommendations how the effects of plume migration can be incorporated into models of repository performance assessment. (author)

  2. Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zonde at Hanford

    International Nuclear Information System (INIS)

    Murray, Christopher J.; Ward, Anderson L.; Wilson, John L.

    2004-01-01

    The purpose of this study was to examine the hypothesis that clastic dikes could form a preferential flow path through the vadose zone to the water table at the Hanford Site. Clastic dikes are subvertical structures that form within sedimentary sequences after deposition and cut across the original sedimentary layers. They are common throughout the Hanford Site, often occurring in organized polygonal networks. In the initial phase of the project, we analyzed the large-scale geometry of the clastic dikes and developed an algorithm for simulating their spatial distribution. This result will be useful in providing maps of the potential distribution of clastic dikes in areas where they are not exposed at the surface (e.g., where covered by windblown sand or construction of facilities like tank farms at the surface). In addition to the study of the large-scale distribution of the dikes, a major focus of the project was on field, laboratory, and modeling studies of the hydrogeological properties of the clastic dikes and the effect that they have on transport of water through the vadose zone. These studies were performed at two field locations at the Hanford Site. We performed an extensive series of field and laboratory measurements of a large number of samples from the clastic dikes, linked with infrared (IR) and visual imagery of the clastic dikes and surrounding matrix. We developed a series of correlations from the sample data that allowed us to estimate the unsaturated hydraulic conductivity of the dike and matrix at an extremely high resolution (approximately 1 mm). The resulting grids, each of which measured several meters on a side and included nearly four million grid nodes, were used to study the distribution of moisture between the clastic dike and surrounding matrix, as well as the relative velocities that moisture would have through the clastic dike and matrix for a number of different recharge scenarios. Results show the development of complex flow networks

  3. Potential for phytoextraction of PCBs from contaminated soils using weeds.

    Science.gov (United States)

    Ficko, Sarah A; Rutter, Allison; Zeeb, Barbara A

    2010-07-15

    A comprehensive investigation of the potential of twenty-seven different species of weeds to phytoextract polychlorinated biphenyls (PCBs) from contaminated soil was conducted at two field sites (Etobicoke and Lindsay) in southern Ontario, Canada. Soil concentrations were 31 microg/g and 4.7 microg/g at each site respectively. All species accumulated PCBs in their root and shoot tissues. Mean shoot concentrations at the two sites ranged from 0.42 microg/g for Chenopodium album to 35 microg/g for Vicia cracca (dry weight). Bioaccumulation factors (BAF=[PCB](plant tissue)/[PCB](mean soil)) at the two sites ranged from 0.08 for Cirsium vulgare to 1.1 for V. cracca. Maximum shoot extractions were 420 microg for Solidago canadensis at the Etobicoke site, and 120 microg for Chrysanthemum leucanthemum at the Lindsay site. When plant density was taken into account with a theoretical density value, seventeen species appeared to be able to extract a similar or greater quantity of PCBs into the shoot tissue than pumpkins (Curcurbita pepo ssp. pepo) which are known PCB accumulators. Therefore, some of these weed species are promising candidates for future phytoremediation studies. Crown Copyright 2010. Published by Elsevier B.V. All rights reserved.

  4. Review of risk from potential emerging contaminants in UK groundwater.

    Science.gov (United States)

    Stuart, Marianne; Lapworth, Dan; Crane, Emily; Hart, Alwyn

    2012-02-01

    This paper provides a review of the types of emerging organic groundwater contaminants (EGCs) which are beginning to be found in the UK. EGCs are compounds being found in groundwater that were previously not detectable or known to be significant and can come from agricultural, urban and rural point sources. EGCs include nanomaterials, pesticides, pharmaceuticals, industrial compounds, personal care products, fragrances, water treatment by-products, flame retardants and surfactants, as well as caffeine and nicotine. Many are relatively small polar molecules which may not be effectively removed by drinking water treatment. Data from the UK Environment Agency's groundwater screening programme for organic pollutants found within the 30 most frequently detected compounds a number of EGCs such as pesticide metabolites, caffeine and DEET. Specific determinands frequently detected include pesticides metabolites, pharmaceuticals including carbamazepine and triclosan, nicotine, food additives and alkyl phosphates. This paper discusses the routes by which these compounds enter groundwater, their toxicity and potential risks to drinking water and the environment. It identifies challenges that need to be met to minimise risk to drinking water and ecosystems. Copyright © 2012. Published by Elsevier B.V.

  5. An approach for assessing potential sediment-bound contaminant threats near the intake of a drinking water treatment plant.

    Science.gov (United States)

    Chen, Fei; Anderson, William B; Huck, Peter M

    2013-01-01

    To assist in assessing a potential contaminated sediment threat near a drinking water intake in a large lake, a technique known as the fingerprint analysis of leachate contaminants (FALCON), was investigated and enhanced to help draw more statistically significant definitive conclusions. This represents the first application of this approach, originally developed by the USEPA to characterize and track leachate penetration in groundwater and contaminant migration from waste and landfill sites, in a large lake from the point-of-view of source water protection. FALCON provided valuable information regarding contaminated sediment characterization, source attribution, and transport within a surface water context without the need for knowledge of local hydrodynamic conditions, potentially reducing reliance on complicated hydrodynamic analysis. A t-test to evaluate the significance of correlations was shown to further enhance the FALCON procedure. In this study, the sensitivity of FALCON was found to be improved by using concentration data from both conserved organics and heavy metals in combination. Furthermore, data analysis indicated that it may be possible to indirectly assess the success of remediation efforts (and the corresponding need to plan for a treatment upgrade in the event of escalating contaminant concentrations) by examining the temporal change in correlation between the source and intake sediment fingerprints over time. This method has potential for widespread application in situations where conserved contaminants such as heavy metals and higher molecular weight polycyclic aromatic hydrocarbons (PAHs), are being or have previously been deposited in sediment somewhere in, or within range of, an intake protection zone. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Potential Risks of Freshwater Aquifer Contamination with Geosequestration

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Robert

    2013-09-30

    Substantial leakage of CO{sub 2} from deep geological strata to shallow potable aquifers is likely to be rare, but chemical detection of potential leakage nonetheless remains an integral component of any safe carbon capture and storage system. CO{sub 2} that infiltrates an unconfined freshwater aquifer will have an immediate impact on water chemistry by lowering pH in most cases and by altering the concentration of total dissolved solids. Chemical signatures in affected waters provide an important opportunity for early detection of leaks. In the presence of CO{sub 2}, trace elements such as Mn, Fe, and Ca can increase by an order of magnitude or more above control concentrations within 100 days. Therefore, these and other elements should be monitored along with pH as geochemical markers of potential CO{sub 2} leaks. Dissolved inorganic carbon and alkalinity can also be rapidly responsive to CO{sub 2} and are stable indicators of a leak. Importantly, such changes may be detectable long before direct changes in CO{sub 2} are observed. The experimental results also suggest that the relative severity of the impact of leaks on overlying drinking-water aquifers should be considered in the selection of CO{sub 2} sequestration sites. One primary selection criteria should be metal and metalloid availability, such as uranium and arsenic abundance, to carefully monitor chemical species that could trigger changes above maximum contaminant levels (MCLs). Overall, the risks of leakage from underground CO{sub 2} storage are real but appear to be manageable if systems are closely monitored.

  7. Clay Characterization as Engineered Barrier to Contaminants Migration: Thermal, Hydraulic and Mechanical Properties

    International Nuclear Information System (INIS)

    Bru, A.; Casero, D.

    2001-01-01

    In this work we characterize the structure of a clay, concretely bentonite. Our main aim is to stress the important role that plays the heterogeneity of the medium structure in transport processes. Randomness of pore sizes produces an anomalous transport of contaminants. We analyze mercuric porosimetry data with simulations finding that pore size distribution has a power-law behaviour. (Author) 6 refs

  8. Immobilization of Lead Migrating from Contaminated Soil in Rhizosphere Soil of Barley (Hordeum vulgare L.) and Hairy Vetch (Vicia villosa) Using Hydroxyapatite.

    Science.gov (United States)

    Katoh, Masahiko; Risky, Elsya; Sato, Takeshi

    2017-10-23

    This study conducted plant growth tests using a rhizobox system to quantitatively determine the distance of immobilization lead migrating from contaminated soil into uncontaminated rhizosphere soil, and to assess the lead phases accumulated in rhizosphere soil by sequential extraction. Without the hydroxyapatite, exchangeable lead fractions increased as the rhizosphere soil got closer to the contaminated soil. Exchangeable lead fractions were higher even in the rhizosphere soil that shares a boundary with the root surface than in the soil before being planted. Thus, plant growth of hairy vetch was lower in the soil without the hydroxyapatite than in the soil with the hydroxyapatite. The presence of hydroxyapatite may immobilize the majority of lead migrating from contaminated soil into the rhizosphere soil within 1 mm from the contaminated soil. The dominant lead fraction in the rhizosphere soil with the hydroxyapatite was residual. Thus, plant growth was not suppressed and the lead concentration of the plant shoot remained at the background level. These results indicate that the presence of hydroxyapatite in the rhizosphere soil at 5% wt may immobilize most of the lead migrating into the rhizosphere soil within 1 mm from the contaminated soil, resulting in the prevention of lead migration toward the root surface.

  9. Potential effect of natural gas wells on alluvial groundwater contamination at the Kansas City Plant

    Energy Technology Data Exchange (ETDEWEB)

    Pickering, D.A.; Laase, A.D. [Oak Ridge National Lab., TN (United States); Locke, D.A. [Oak Ridge Inst. for Science and Education, TN (United States)

    1993-05-01

    This report is the result of a request for further information about several abandoned natural gas wells at the US Department of Energy`s Kansas City Plant (KCP). The request was prompted by an old map showing several, possibly eight, natural gas wells located under or near what is now the southeast corner of the Main Manufacturing Building at KCP. Volatile organic compound contamination in the alluvial aquifer surrounding the gas wells might possibly contaminate the bedrock aquifer if the gas wells still exist as conduits. Several circumstances exist that make it doubtful that contamination is entering the bedrock aquifers: (1) because regional groundwater flow in the bedrock beneath the KCP is expected to be vertically upward, contaminants found in the alluvial aquifer should not migrate down the old wells; (2) because of the low hydraulic conductivity of the bedrock units, contaminant transport would be extremely slow if the contaminants were migrating down the wells; and (3) casing, apparently set through the alluvium in all of the wells, would have deteriorated and may have collapsed; if the casing collapsed, the silty clays in the alluvium would also collapse and seal the well. No definitive information has been discovered about the exact location of the wells. No further search for or consideration of the old gas wells is recommended.

  10. Potential effect of natural gas wells on alluvial groundwater contamination at the Kansas City Plant

    Energy Technology Data Exchange (ETDEWEB)

    Pickering, D.A.; Laase, A.D. (Oak Ridge National Lab., TN (United States)); Locke, D.A. (Oak Ridge Inst. for Science and Education, TN (United States))

    1993-05-01

    This report is the result of a request for further information about several abandoned natural gas wells at the US Department of Energy's Kansas City Plant (KCP). The request was prompted by an old map showing several, possibly eight, natural gas wells located under or near what is now the southeast corner of the Main Manufacturing Building at KCP. Volatile organic compound contamination in the alluvial aquifer surrounding the gas wells might possibly contaminate the bedrock aquifer if the gas wells still exist as conduits. Several circumstances exist that make it doubtful that contamination is entering the bedrock aquifers: (1) because regional groundwater flow in the bedrock beneath the KCP is expected to be vertically upward, contaminants found in the alluvial aquifer should not migrate down the old wells; (2) because of the low hydraulic conductivity of the bedrock units, contaminant transport would be extremely slow if the contaminants were migrating down the wells; and (3) casing, apparently set through the alluvium in all of the wells, would have deteriorated and may have collapsed; if the casing collapsed, the silty clays in the alluvium would also collapse and seal the well. No definitive information has been discovered about the exact location of the wells. No further search for or consideration of the old gas wells is recommended.

  11. Potential effect of natural gas wells on alluvial groundwater contamination at the Kansas City Plant

    International Nuclear Information System (INIS)

    Pickering, D.A.; Laase, A.D.; Locke, D.A.

    1993-05-01

    This report is the result of a request for further information about several abandoned natural gas wells at the US Department of Energy's Kansas City Plant (KCP). The request was prompted by an old map showing several, possibly eight, natural gas wells located under or near what is now the southeast corner of the Main Manufacturing Building at KCP. Volatile organic compound contamination in the alluvial aquifer surrounding the gas wells might possibly contaminate the bedrock aquifer if the gas wells still exist as conduits. Several circumstances exist that make it doubtful that contamination is entering the bedrock aquifers: (1) because regional groundwater flow in the bedrock beneath the KCP is expected to be vertically upward, contaminants found in the alluvial aquifer should not migrate down the old wells; (2) because of the low hydraulic conductivity of the bedrock units, contaminant transport would be extremely slow if the contaminants were migrating down the wells; and (3) casing, apparently set through the alluvium in all of the wells, would have deteriorated and may have collapsed; if the casing collapsed, the silty clays in the alluvium would also collapse and seal the well. No definitive information has been discovered about the exact location of the wells. No further search for or consideration of the old gas wells is recommended

  12. A two-reagent neutralization scheme for controlling the migration of contaminants from a uranium mill tailing disposal pond

    International Nuclear Information System (INIS)

    Dodson, M.E.; Opitz, B.E.; Sherwood, D.R.

    1985-01-01

    Techniques for reducing contaminant migration from tailings liquor impoundments and evaporation ponds are being investigated by the Pacific Northwest Laboratory as part of the Nuclear Regulatory Commission's Uranium Research and Recovery Program. Building upon previous studies investigating single-reagent neutralization, laboratory experiments were conducted to evaluate the performance of a two-reagent neutralization scheme for the treatment of acidic uranium mill tailings liquors. Acidic tailings liquor, pH 3 neutralization to pH 4.0 followed by continued neutralization with lime to pH 7.3, resulted in the highest solution quality with respect to the Environmental Protection Agency's water quality guidelines. Furthermore, the two-reagent neutralization scheme is the most cost-effective treatment procedure tested to date

  13. Two-reagent neutralization scheme for controlling the migration of contaminants from a uranium mill tailings disposal pond

    International Nuclear Information System (INIS)

    Dodson, M.E.; Opitz, B.E.; Sherwood, D.R.

    1984-11-01

    Techniques for reducing contaminant migration from tailings liquor impoundments and evaporation ponds are being investigated by the Pacific Northwest Laboratory as part of the Nuclear Regulatory Commission's Uranium Research and Recovery Program. Building upon previous studies investigating single-reagent neutralization, laboratory experiments were conducted to evaluate the performance of a two-reagent neutralization scheme for the treatment of acidic uranium mill tailings liquors. Acidic tailings liquor, pH 3 neutralization to pH 4.0 followed by continued neutralization with lime to pH 7.3, resulted in the highest solution quality with respect to the Environmental Protection Agency's water quality guidelines. Furthermore, the two-reagent neutralization scheme is the most cost-effective treatment procedure tested to date. 13 references, 1 table

  14. A novel method for the determination of migration of contaminants from food contact materials

    International Nuclear Information System (INIS)

    Thompson, D.; Parry, S.J.; Benzing, R.

    1996-01-01

    A neutron activation method has been developed for the analysis of high density polyethylene, low density polyethylene, polypropylene, polyethylene terephthalate and polystyrene food contact plastics. The method provides determination of over 50 elements at concentrations below 1 mg kg -1 . This technique has now been extended to study migration from food contact materials into standard food simulants (olive oil, acetic acid, ethanol and water). Samples of plastic are irradiated in a thermal neutron flux to procedure radionuclides of the elements present in the plastic. (author). 5 refs., 7 tabs

  15. Potential Human Health Risks of Tannery Waste-contaminated Poultry Feed

    Directory of Open Access Journals (Sweden)

    Mohammad Latiful Bari

    2015-01-01

    Conclusions. The estimated daily intake value, THQ, along with the aggregate hazard index value, indicated a potential risk to consumers through consumption of contaminated chicken. Therefore, the study results clearly demonstrate heavy metals accumulation in chicken due to feeding SCW-based feed. The contaminated chicken further transfers these heavy metals to humans through ingestion. Hence, there is a potential human health risk through consumption of contaminated chicken meat.

  16. NCRP soil contamination task group

    International Nuclear Information System (INIS)

    Jacobs, D.G.

    1987-01-01

    The National Council of Radiation Protection and Measurements (NCRP) has recently established a Task Group on Soil Contamination to describe and evaluate the migration pathways and modes of radiation exposure that can potentially arise due to radioactive contamination of soil. The purpose of this paper is to describe the scientific principles for evaluation of soil contamination which can be used as a basis for derivation of soil contamination limits for specific situations. This paper describes scenarios that can lead to soil contamination, important characteristics of soil contamination, the subsequent migration pathways and exposure modes, and the application of principles in the report in deriving soil contamination limits. The migration pathways and exposure modes discussed in this paper include: direct radiation exposure; and exhalation of gases

  17. Contamination and migration of Chernobyl radiocaesium in upland soils of NE Italy

    International Nuclear Information System (INIS)

    Giovani, C.; Padovani, R.; Fadone, A.; Scruzzi, E.

    1994-01-01

    The behaviour of radiocaesium from Chernobyl fallout undisturbed soils of the mountain areas of Friuli-Venezia Giulia region (NE Italy) has been monitored by sampling surveys carried out in 1987, 1988 and 1990. About 800 soil samples were collected in 55 sites to estimate radiocaesium inventories the upper 10 cm layer of soil. Vertical profiles consisting of 4 to 7 samples were also collected to detect downward migration of radiocaesium. Surface activities are presented and discussed with regard to different ecosystems. The main features of the pattern of deposition on undisturbed fields and forests are outlined. The behaviour of radiocaesium in the environment is interpreted on the basis of results from the comparison of the three sets of samples

  18. contaminant migration in a sand aquifer near an inactive uranium tailings impoundment, Elliot Lake, Ontario

    International Nuclear Information System (INIS)

    Morin, K.A.; Cherry, J.A.

    1982-01-01

    An investigation of the movement of contaminated groundwater from inactive uranium tailings through a sand aquifer is being conducted at the Nordic Main tailings impoundment near Elliot Lake, Ontario. During 1979 and 1980, multilevel bundle-type piezometers were installed at several locations around the edge of the tailings impoundment. Chemical analysis of water samples from the bundle piezometers indicate that a major contaminant plume extends outward through a sand aquifer from the southeastern part of the Nordic Main impoundment dam. In the vincinity of the contaminant plume, the sand aquifer varies in thickness from about 9 to 15 m. The plume has two distinct segments, referred to as the inner core and the outer zone. The inner core, which has a pH of 4.3-5.0 and extends about 15 m from the foot of the tailings dam, contains several grams per litre of iron and sulfate, and tens of pCi/L of 226 Ra and 210 Pb. Water levels in piezometers within the inner core show that groundwater is moving horizontally, away from the tailings impoundment, with a velocity of up to several hundred metres per year. The outer zone, which extends a few hundred metres downgradient from the dam, is characterized by hundreds to thousands of milligrams per litre of iron and sulfate, less than 15pCi/L of 226 Ra, and a pH greater than 5.7. Comparison of 1979 and 1980 data shows that the front of the inner core is advancing a few metres per year, which is less than a few percent of the groundwater velocity. This retardation of movement of the inner core is caused by neutralization of the acidic water as a result of dissolution of calcium carbonate in the sand. With the rise in pH, precipitation of iron carbonate and possibly some iron hydroxide occurs and the contaminants of main concern such as 226 Ra, 210 Pb, and uranium are removed from solution by adsorption or coprecipitation

  19. Inorganic Contaminants in Recycled Packaging: Potential Impact for Consumer Safety

    International Nuclear Information System (INIS)

    S. J. Parry; D. S. J. Aston

    2000-01-01

    The effect on human health of using food packaging made from recycled materials will depend on whether the elements will migrate into the food itself and at which levels that would be of concern. There is no EU directive for paper and board packaging, but guidelines on paper and board intended to come into contact with food are being developed in another forum. These do not propose limits for paper intended to come into contact with dry foods. However, for other foodstuffs, restriction limits in paper of 0.002 mg/dm 2 (Cd), 0.003 mg/dm 2 (Pb), and 0.002 mg/dm 2 (Hg) have been proposed. This paper describes a radiotracer method that has been applied to the determination of migration of trace elements from paper and board into real food samples

  20. Effects of crystalline FE and MN oxides on contaminant migration through soil liners

    International Nuclear Information System (INIS)

    Dodson, M.E.; Serne, R.J.; Gee, G.W.

    1983-12-01

    Tailings solution, produced from tailings excavated at the Canonsburg, Pennsylvania UMTRAP site, was used in liner material column flow studies to test the attenuation characteristics of local borrow pit soil found adjacent to the tailings area. The effluents from linear columns, under saturated conditions, were sampled at fractional pore volumes and analyzed for macro cation, anion, trace metal and radionuclide contents. Solution displacement was allowed to continue until three pore volumes of tailings solution had contacted the liner material. In addition, two amended liner mixtures were contacted with Canonsburg tailings solution to assess the effects of crystalline iron and manganese oxides in attenuating contaminants. The amended mixes represented Canonsburg soil plus either 2% (dry wt basis) reagent grade iron oxide of 2% manganese saturated green sand zeolite. Attenuation of most trace metals and readionuclides was high in all three column studies, while macro ions, zinc, and the anions Cl and SO 4 showed limited signs of attenuation regardless of whether the soil was amended or not. In addition, there were no signs of excess leaching to Fe or Mn from the columns enriched with their oxides. General results indicate that the addition of iron and manganese oxides in their crystalline form is of little additional value compared to the attenuation of contaminants achieved with native iron and manganese oxides found as partial coatings on the silicate minerals of the unamended Canonsburg soil. 8 references, 3 figures, 3 tables

  1. The effects of crystalline Fe and Mn oxides on contaminant migration through soil liners

    International Nuclear Information System (INIS)

    Dodson, M.E.; Gee, G.W.; Serne, R.J.

    1984-01-01

    Tailings solution, produced from tailings excavated at the Canonsburg, Pennsylvania UMTRAP site, was used in liner material column flow studies to test the attenuation characteristics of local borrow pit soil found adjacent to the tailings area. The effluents from liner columns, under saturated conditions, were sampled at fractional pore volumes and analyzed for macro cation, anion, trace metal and radionuclide contents. Solution displacement was allowed to continue until three pore volumes of tailings solution had contacted the liner material. In addition, two amended liner mixtures were contacted with Canonsburg tailings solution to assess the effects of crystalline iron and manganese oxides in attenuating contaminants. The amended mixes represented Canonsburg soil plus either 2% (dry wt. basis) reagent grade iron oxide or 2% manganese saturated green sand zeolite. Attenuation of most trace metals and radionuclides was high in all three column studies, while macro ions, zinc, and the anions C1 and SO 4 showed limited signs of attenuation regardless of whether the soil was amended or not. In addition, there were no signs of excess leaching of Fe or Mn from the columns enriched with their oxides. General results indicate that the addition of iron and manganese oxides in their crystaline form is of little additional value compared to the attenuation of contaminants achieved with native iron and manganese oxides found as partial coatings on the silicate minerals of the unamended Canonsburg soil

  2. Experimental Study of Airborne Contaminant Migration in an Aircraft Cabin Model

    Science.gov (United States)

    Poussou, Stephane; Sojka, Paul; Plesniak, Michael

    2007-11-01

    The cabin air ventilation system in wide body jetliners is designed to provide a comfortable and controlled environment for passengers. Inside the cabin, the air flows continuously from overhead vents into sidewall exhausts, forming a circular pattern designed to minimize cross flow between adjacent seat rows. However, spreading of gaseous or particulate contaminants is possible when flight attendants or passengers walk along an aisle, perturbing the ventilation flow. Such unsteady flow perturbations have been found to alter the cabin air distribution and quality. A better fundamental understanding of the turbulent transport phenomena is needed to improve air quality monitoring and control systems and to validate numerical simulations. The velocity field in a 15:1 model of a simplified aircraft cabin is probed to investigate the wake of a rectangular body moving through a steady two-dimensional flow at a Reynolds number (based on body height) of the order of 50,000. Planar Laser Induced Fluorescence is used to visualize wake structure and scalar contaminant transport. The interaction between the wake and the ventilation flow is measured with PIV. The data are compared to numerical studies of cabin airflows in the literature.

  3. Monitoring Potential Transport of Radioactive Contaminants in Shallow Ephemeral Channels: FY2015 and FY2016

    Energy Technology Data Exchange (ETDEWEB)

    Mizell, Steve A [Desert Research Inst. (DRI), Las Vegas, NV (United States); Miller, Julianne J [Desert Research Inst. (DRI), Las Vegas, NV (United States); McCurdy, Greg [Desert Research Inst. (DRI), Las Vegas, NV (United States); Campbell, Scott A [Desert Research Inst. (DRI), Las Vegas, NV (United States)

    2017-10-01

    The Desert Research Institute (DRI) is conducting a field assessment of the potential for contaminated soil to be transported from the Smoky Contamination Area (CA) as a result of storm runoff. This activity supports Nevada Nuclear Security Administration (NNSA) efforts to complete regulatory closure of the Soils Corrective Action Unit (CAU) contamination areas. The work is intended to confirm the likely mechanism of transport and determine the meteorological conditions that might cause movement of contaminated soils, as well as determine the particle size fraction that is most closely associated with transported radionuclide-contaminated soils. These data will facilitate the appropriate closure design and post-closure monitoring program.

  4. Monitoring Potential Transport of Radioactive Contaminants in Shallow Ephemeral Channels: FY2013 and FY2014 (revised)

    Energy Technology Data Exchange (ETDEWEB)

    Mizell, Steve A. [Desert Research Inst. (DRI), Las Vegas, NV (United States); Miller, Julianne J. [Desert Research Inst. (DRI), Las Vegas, NV (United States); McCurdy, Greg D. [Desert Research Inst. (DRI), Reno, NV (United States); Campbell, Scott A. [Desert Research Inst. (DRI), Las Vegas, NV (United States)

    2017-06-01

    The Desert Research Institute (DRI) is conducting a field assessment of the potential for contaminated soil to be transported from the Smoky Contamination Area (CA) as a result of storm runoff, which supports National Nuclear Security Administration (NNSA) efforts to complete regulatory closure of the Soils Corrective Action Unit (CAU) contamination areas. The work is intended to confirm the likely mechanism of transport and determine the meteorological conditions that might cause movement of contaminated soils, as well as determine the particle size fraction that is most closely associated with transported radionuclide-contaminated soils. These data will facilitate the appropriate closure design and post-closure monitoring program.

  5. Creosote-contaminated sites: their potential for bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, J G; Chapman, P J; Pritchard, P H [US EPA Environmental Research Laboratory, Gulf Breeze, FL (USA)

    1989-10-01

    Coal tar creosote contamination is generally associated with surface soils, waters in treatment lagoons or evaporation areas, and groundwater contaminated with leachate from the above sources. The basic principle of bioremediation is to exploit the ability of microorganisms to catabolize a wide range of organic substrates. There are limitations which much be addressed if in situ bioremediation is to be successful: the pollutant must be in a chemical state conducive to microbial utilization, aeration and nutrient supplementation are essential elements of many in situ treatments, and there must be present an acclimated microbial population capable of degrading the pollutant. 35 refs., 3 tabs.

  6. Increased migration of monocytes in essential hypertension is associated with increased transient receptor potential channel canonical type 3 channels

    DEFF Research Database (Denmark)

    Zhao, Zhigang; Ni, Yinxing; Chen, Jing

    2012-01-01

    Increased transient receptor potential canonical type 3 (TRPC3) channels have been observed in patients with essential hypertension. In the present study we tested the hypothesis that increased monocyte migration is associated with increased TRPC3 expression. Monocyte migration assay was performe...

  7. Bioremediation potential of diesel-contaminated Libyan soil.

    Science.gov (United States)

    Koshlaf, Eman; Shahsavari, Esmaeil; Aburto-Medina, Arturo; Taha, Mohamed; Haleyur, Nagalakshmi; Makadia, Tanvi H; Morrison, Paul D; Ball, Andrew S

    2016-11-01

    Bioremediation is a broadly applied environmentally friendly and economical treatment for the clean-up of sites contaminated by petroleum hydrocarbons. However, the application of this technology to contaminated soil in Libya has not been fully exploited. In this study, the efficacy of different bioremediation processes (necrophytoremediation using pea straw, bioaugmentation and a combination of both treatments) together with natural attenuation were assessed in diesel contaminated Libyan soils. The addition of pea straw was found to be the best bioremediation treatment for cleaning up diesel contaminated Libyan soil after 12 weeks. The greatest TPH degradation, 96.1% (18,239.6mgkg(-1)) and 95% (17,991.14mgkg(-1)) were obtained when the soil was amended with pea straw alone and in combination with a hydrocarbonoclastic consortium respectively. In contrast, natural attenuation resulted in a significantly lower TPH reduction of 76% (14,444.5mgkg(-1)). The presence of pea straw also led to a significant increased recovery of hydrocarbon degraders; 5.7log CFU g(-1) dry soil, compared to 4.4log CFUg(-1) dry soil for the untreated (natural attenuation) soil. DGGE and Illumina 16S metagenomic analyses confirm shifts in bacterial communities compared with original soil after 12 weeks incubation. In addition, metagenomic analysis showed that original soil contained hydrocarbon degraders (e.g. Pseudoxanthomonas spp. and Alcanivorax spp.). However, they require a biostimulant (in this case pea straw) to become active. This study is the first to report successful oil bioremediation with pea straw in Libya. It demonstrates the effectiveness of pea straw in enhancing bioremediation of the diesel-contaminated Libyan soil. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Actinide migration from contaminated soil to surface water at the rocky flats environmental technology site

    International Nuclear Information System (INIS)

    Santschi, Peter H.; Roberts, Kimberly

    2002-01-01

    Surficial soils of the Rocky Flats Environmental Technology Site (RFETS) contain elevated levels of 239,240 Pu and 241 Am due to wind dispersal of soil particles, contaminated in the 1960's by leaking drums stored on the 903 Pad. Over the past 4 years, actinide mobility in the surface environment at RFETS, Golden, Colorado, USA, was examined through field and laboratory experiments. From measurements of total 239,240 Pu and 241 Am concentrations in storm runoff and pond discharge samples, collected during spring and summer times, it was established that most of the actinide transport from contaminated soils to streams occurred in the particulate (0.45μm) and colloidal (3kDa - 0.45μm) phases. Controlled laboratory investigations of soil resuspension, indicated that remobilization of colloid-bound Pu during soil erosion events can be enhanced by humic acids. 2-D Polyacrylamide Gel electrophoresis (PAGE) experiments of radiolabeled colloidal organic and inorganic matter, extracted from RFETS soils, suggested that colloidal Pu, which was focused at pH IEP of 4.5, is mainly associated with organic (humic acids) colloids of 10-15 kDa molecular weight. Pu(IV) oxide and inorganic colloids such as iron and aluminum oxides have pH IEP of 8-10. While some clay minerals also have pH IEP of 3-5, no Al was found coincident with Pu. This finding has important ramifications for possible remediation, erosion controls, and land-management strategies. (author)

  9. Hydrodebridement of wounds: effectiveness in reducing wound bacterial contamination and potential for air bacterial contamination.

    Science.gov (United States)

    Bowling, Frank L; Stickings, Daryl S; Edwards-Jones, Valerie; Armstrong, David G; Boulton, Andrew Jm

    2009-05-08

    The purpose of this study was to assess the level of air contamination with bacteria after surgical hydrodebridement and to determine the effectiveness of hydro surgery on bacterial reduction of a simulated infected wound. Four porcine samples were scored then infected with a broth culture containing a variety of organisms and incubated at 37 degrees C for 24 hours. The infected samples were then debrided with the hydro surgery tool (Versajet, Smith and Nephew, Largo, Florida, USA). Samples were taken for microbiology, histology and scanning electron microscopy pre-infection, post infection and post debridement. Air bacterial contamination was evaluated before, during and after debridement by using active and passive methods; for active sampling the SAS-Super 90 air sampler was used, for passive sampling settle plates were located at set distances around the clinic room. There was no statistically significant reduction in bacterial contamination of the porcine samples post hydrodebridement. Analysis of the passive sampling showed a significant (p air whilst using hydro surgery equipment compared with a basal count of 582 CFUs/m3. During removal of the wound dressing, a significant increase was observed relative to basal counts (p air samples was still significantly raised 1 hour post-therapy. The results suggest a significant increase in bacterial air contamination both by active sampling and passive sampling. We believe that action might be taken to mitigate fallout in the settings in which this technique is used.

  10. Review of risk from potential emerging contaminants in UK groundwater

    OpenAIRE

    Stuart, Marianne; Lapworth, Dan; Crane, Emily; Hart, Alwyn

    2012-01-01

    This paper provides a review of the types of emerging organic groundwater contaminants (EGCs) which are beginning to be found in the UK. EGCs are compounds being found in groundwater that were previously not detectable or known to be significant and can come from agricultural, urban and rural point sources. EGCs include nanomaterials, pesticides, pharmaceuticals, industrial compounds, personal care products, fragrances, water treatment by-products, flame retardants and surfactants, as well a...

  11. Monosilicic acid potential in phytoremediation of the contaminated areas.

    Science.gov (United States)

    Ji, Xionghui; Liu, Saihua; Huang, Juan; Bocharnikova, Elena; Matichenkov, Vladimir

    2016-08-01

    The contamination of agricultural areas by heavy metals has a negative influence on food quality and human health. Various remediation techniques have been developed for the removal and/or immobilization of heavy metals (HM) in contaminated soils. Phytoremediation is innovative technology, which has advantages (low cost, easy monitoring, high selectivity) and limitations, including long time for procedure and negative impact of contaminants on used plants. Greenhouse investigations have shown that monosilicic acid can be used for regulation of the HM (Cd, Cr, Pb and Zn) mobility in the soil-plant system. If the concentration of monosilicic acid in soil was increased from 0 to 20 mg L(-1) of Si in soil solution, the HM bioavailability was increased by 30-150%. However, the negative influence on the barley by HM was reduced under monosilicic acid application. If the concentration of monosilicic acid was increased more than 20 mg L(-1), the HM mobility in the soil was decreased by 40-300% and heavy metal uptake by plants was reduced 2-3 times. The using of the monosilicic acid may increase the phytoremediation efficiency. However the technique adaptation will be necessary for phytoremediation on certain areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Erratum: potential microbial contamination during sampling of permafrost soil assessed by tracers

    DEFF Research Database (Denmark)

    Bang-Andreasen, Toke; Schostag, Morten Dencker; Priemé, Anders

    2017-01-01

    Drilling and handling of permanently frozen soil cores without microbial contamination is of concern because contamination e.g. from the active layer above may lead to incorrect interpretation of results in experiments investigating potential and actual microbial activity in these low microbial b...

  13. Predictive geochemical modeling of contaminant concentrations in laboratory columns and in plumes migrating from uranium mill tailings waste impoundments

    International Nuclear Information System (INIS)

    Peterson, S.R.; Martin, W.J.; Serne, R.J.

    1986-04-01

    A computer-based conceptual chemical model was applied to predict contaminant concentrations in plumes migrating from a uranium mill tailings waste impoundment. The solids chosen for inclusion in the conceptual model were selected based on reviews of the literature, on ion speciation/solubility calculations performed on the column effluent solutions and on mineralogical characterization of the contacted and uncontacted sediments. The mechanism of adsorption included in the conceptual chemical model was chosen based on results from semiselective extraction experiments and from mineralogical characterization procedures performed on the sediments. This conceptual chemical model was further developed and partially validated in laboratory experiments where assorted acidic uranium mill tailings solutions percolated through various sediments. This document contains the results of a partial field and laboratory validation (i.e., test of coherence) of this chemical model. Macro constituents (e.g., Ca, SO 4 , Al, Fe, and Mn) of the tailings solution were predicted closely by considering their concentrations to be controlled by the precipitation/dissolution of solid phases. Trace elements, however, were generally predicted to be undersaturated with respect to plausible solid phase controls. The concentration of several of the trace elements were closely predicted by considering their concentrations to be controlled by adsorption onto the amorphous iron oxyhydroxides that precipitated

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

    International Nuclear Information System (INIS)

    Lajoie, C.A.

    1991-01-01

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

  15. Fly pupae and puparia as potential contaminants of forensic entomology samples from sites of body discovery.

    Science.gov (United States)

    Archer, M S; Elgar, M A; Briggs, C A; Ranson, D L

    2006-11-01

    Fly pupae and puparia may contaminate forensic entomology samples at death scenes if they have originated not from human remains but from animal carcasses or other decomposing organic material. These contaminants may erroneously lengthen post-mortem interval estimates if no pupae or puparia are genuinely associated with the body. Three forensic entomology case studies are presented, in which contamination either occurred or was suspected. In the first case, blow fly puparia collected near the body were detected as contaminants because the species was inactive both when the body was found and when the deceased was last sighted reliably. The second case illustrates that contamination may be suspected at particularly squalid death scenes because of the likely presence of carcasses or organic material. The third case involves the presence at the body discovery site of numerous potentially contaminating animal carcasses. Soil samples were taken along transects to show that pupae and puparia were clustered around their probable sources.

  16. Sources, migration and transformation of antimony contamination in the water environment of Xikuangshan, China: Evidence from geochemical and stable isotope (S, Sr) signatures

    International Nuclear Information System (INIS)

    Wen, Bing; Zhou, Jianwei; Zhou, Aiguo; Liu, Cunfu; Xie, Lina

    2016-01-01

    The Xikuangshan (XKS) mine in central China is the largest antimony (Sb) mine in the world. The mining activity has seriously contaminated the waters in the area. To determine the sources, migration and transformation of Sb contamination, 32 samples from groundwater (aquifer water), surface water and mine water were collected for water chemistry, trace element and S_S_O_4 and Sr stable isotope analyses. The results showed that the groundwater and surface water were in an oxidized environment. The S_S_O_4 and Sr isotope compositions in the water indicated that dissolved Sb and SO_4"2 originated from sulfide mineral (Sb_2S_3) oxidation, whereas radiogenic Sr may have been sourced from silicified limestone and stibnite in the Shetianqiao aquifer. Furthermore, a positive correlation between δ"3"4S_S_O_4 and δ"8"7Sr values revealed that the Sr, S and Sb in the waters had a common contamination source, i.e., silicified limestone and stibnite, whereas the Sr, S and Sb in rock and ore were sourced from Proterozoic basement clastics. The analysis also indicated that the isotope composition of dissolved SO_4"2 "− had been influenced by slight bacterial SO_4 reduction in the Magunao aquifer. Mining or rock collapse may have caused Shetianqiao aquifer water to contaminate the Magunao aquifer water via mixing. This study has demonstrated that the stable isotopes of "3"4S_S_O_4 and "8"7Sr, combined with hydrochemical methods, are effective in tracking the sources, migration and transformation of Sb contamination. - Highlights: • Mining activities at XKS mine have caused serious water contamination. • The characteristics of Sb contamination in water environment are still unclear. • Combine S isotopes of sulfate and Sr isotopes with hydrochemical methods. • Sr, S, and Sb in natural water had a common source: silicified limestone and stibnite. • Shetianqiao aquifer water contaminated the Magunao aquifer water via mixing.

  17. Stray dogs and cats as potential sources of soil contamination with zoonotic parasites

    Directory of Open Access Journals (Sweden)

    Katarzyna Szwabe

    2017-03-01

    Cat faeces represent a more important potential source of environmental contamination with zoonotic parasites than dog faeces. Among the detected parasites of stray dogs and cats, Toxocara present an important zoonotic risk for the local human population, especially children.

  18. Evaluating cadmium bioavailability in contaminated rice paddy soils and assessing potential for contaminant immobilisation with biochar.

    Science.gov (United States)

    Kosolsaksakul, Peerapat; Oliver, Ian W; Graham, Margaret C

    2018-06-01

    Cadmium (Cd) contaminated soils from the Mae Sot district in northwest Thailand, a region in which rice Cd concentrations often exceed health limits (0.4 mg/kg) set by the World Health Organisation, were examined for isotopically exchangeable Cd (Cd E values using a 111 Cd spike) to determine how this rates as a predictor of rice grain Cd in comparison with soil total Cd and solution extractable Cd (using the commonly applied BCR scheme and, in an attempt to distinguish carbonate bound forms, the Tessier soil sequential extraction scheme reagents). Step 1 of the BCR scheme (0.11 M CH 3 COOH) and step 1 of the Tessier scheme (1M MgCl 2 ) showed the highest R 2 values in regressions with rice Cd (91% and 90%, respectively), but all predictors were strongly linked to rice Cd (p soil, of the six tested, was an exception to this, where all predictors over-estimated grain Cd by a factor of 2.5-5.7, suggesting that rice grain Cd had been restricted here by the differing flooding regime and subsequent changes to redox conditions. E values and Tessier step 1 extractions were closely related, indicating that these measurements access similar pools of soil Cd. Separately, the isotopic exchangeability (representing bioavailability) of Cd was also assessed in two soils amended with rice husk and miscanthus biochars (0, 1, 5, 10, 15 and 20% w/w) in order to assess the utility of the biochars as a soil amendment for immobilising Cd in situ. One soil showed significant reductions in Cd E value at 5% rice husk biochar addition and at 15% miscanthus biochar addition however, based on the E value-rice grain Cd regression relationship previously established, the E values in the amended soils still predicted for a rice Cd concentration above the health limit. In the second soil, neither of the biochars successfully reduced the Cd E value. This indicates that further work is needed to customise biochar properties to suit specific soil and contaminant situations if they are to be

  19. Redox potential distribution of an organic-rich contaminated site obtained by the inversion of self-potential data

    Science.gov (United States)

    Abbas, M.; Jardani, A.; Soueid Ahmed, A.; Revil, A.; Brigaud, L.; Bégassat, Ph.; Dupont, J. P.

    2017-11-01

    Mapping the redox potential of shallow aquifers impacted by hydrocarbon contaminant plumes is important for the characterization and remediation of such contaminated sites. The redox potential of groundwater is indicative of the biodegradation of hydrocarbons and is important in delineating the shapes of contaminant plumes. The self-potential method was used to reconstruct the redox potential of groundwater associated with an organic-rich contaminant plume in northern France. The self-potential technique is a passive technique consisting in recording the electrical potential distribution at the surface of the Earth. A self-potential map is essentially the sum of two contributions, one associated with groundwater flow referred to as the electrokinetic component, and one associated with redox potential anomalies referred to as the electroredox component (thermoelectric and diffusion potentials are generally negligible). A groundwater flow model was first used to remove the electrokinetic component from the observed self-potential data. Then, a residual self-potential map was obtained. The source current density generating the residual self-potential signals is assumed to be associated with the position of the water table, an interface characterized by a change in both the electrical conductivity and the redox potential. The source current density was obtained through an inverse problem by minimizing a cost function including a data misfit contribution and a regularizer. This inversion algorithm allows the determination of the vertical and horizontal components of the source current density taking into account the electrical conductivity distribution of the saturated and non-saturated zones obtained independently by electrical resistivity tomography. The redox potential distribution was finally determined from the inverted residual source current density. A redox map was successfully built and the estimated redox potential values correlated well with in

  20. Potential soil contaminant levels of polychlorinated dibenzodioxins and dibenzofurans at industrial facilities employing heat transfer operations

    Energy Technology Data Exchange (ETDEWEB)

    Korte, N.E.; Muhr, C.A.; Greene, D.W.

    1992-04-01

    Certain manufacturing facilities formerly used large quantities of polychlorinated biphenyl (PCB) fluids in heat transfer operations. At many of these locations, operations have also involved PCB-containing electrical equipment. Commonly, over many years of plant operations, spills and leaks have resulted in PCB soil contamination. Dioxins and furans have been associated with PCB contamination in both the technical and popular press. Consequently, the need for analyses for dioxins and furans must be evaluated at locations where soils are contaminated with PCBs. This report presents an evaluation of potential dioxin and furan soil contamination based on heat transfer operations and spills from electrical equipment. The following five scenarios were examined for dioxin and furan contamination: (1) impurities in heat transfer fluids, (2) formation during heat transfer operations, (3) pyrolysis of heat transfer fluids, (4) impurities in dielectric fluids, and (5) pyrolysis of dielectric fluids. The potential contamination with dioxins and furans was calculated and compared with a 20 ppb guideline that has been used by the Centers for Disease Control for dioxin in subsoil. The results demonstrated that dioxins are formed only under pyrolytic conditions and only from the trichlorobenzenes present in dielectric fluids. Furans are found as impurities in PCB fluids but, as with dioxins, are not formed in significant quantities except during pyrolysis. Fortunately, pyrolytic conditions involving PCB fluids and soil contamination are unlikely; therefore, analyses for dioxin and furan contamination in soils will rarely be needed.

  1. Contamination potential of drinking water distribution network biofilms.

    Science.gov (United States)

    Wingender, J; Flemming, H C

    2004-01-01

    Drinking water distribution system biofilms were investigated for the presence of hygienically relevant microorganisms. Early biofilm formation was evaluated in biofilm reactors on stainless steel, copper, polyvinyl chloride (PVC) and polyethylene coupons exposed to unchlorinated drinking water. After 12 to 18 months, a plateau phase of biofilm development was reached. Surface colonization on the materials ranged between 4 x 10(6) and 3 x 10(7) cells/cm2, with heterotrophic plate count (HPC) bacteria between 9 x 10(3) and 7 x 10(5) colony-forming units (cfu)/cm2. Established biofilms were investigated in 18 pipe sections (2 to 99 years old) cut out from distribution pipelines. Materials included cast iron, galvanized steel, cement and PVC. Colonization ranged from 4 x 10(5) to 2 x 10(8) cells/cm2, HPC levels varied between 1 and 2 x 10(5) cfu/cm2. No correlation was found between extent of colonization and age of the pipes. Using cultural detection methods, coliform bacteria were rarely found, while Escherichia coli, Pseudomonas aeruginosa and Legionella spp. were not detected in the biofilms. In regular operation, distribution system biofilms do not seem to be common habitats for pathogens. However, nutrient-leaching materials like rubber-coated valves were observed with massive biofilms which harboured coliform bacteria contaminating drinking water.

  2. Prevention of polydimethylsiloxane microsphere migration using a mussel-inspired polydopamine coating for potential application in injection therapy.

    Directory of Open Access Journals (Sweden)

    Eun-Jae Chung

    Full Text Available The use of injectable bulking agents is a feasible alternative procedure for conventional surgical therapy. In this study, poly(dimethylsiloxane (PDMS microspheres coated with polydopamine (PDA were developed as a potential injection agent to prevent migration in vocal fold. Uniform PDMS microspheres are fabricated using a simple fluidic device and then coated with PDA. Cell attachment test reveals that the PDA-coated PDMS (PDA-PDMS substrate favors cell adhesion and attachment. The injected PDA-PDMS microspheres persist without migration on reconstructed axial CT images, whereas, pristine PDMS locally migrates over a period of 12 weeks. The gross appearance of the implants retrieved at 4, 8, 12 and 34 weeks indicates that the PDA-PDMS group maintained their original position without significant migration until 34 weeks after injection. By contrast, there is diffuse local migration of the pristine PDMS group from 4 weeks after injection. The PDA-coated PDMS microspheres can potentially be used as easily injectable, non-absorbable filler without migration.

  3. Evaluating Potential Human Health Risks Associated with the Development of Utility-Scale Solar Energy Facilities on Contaminated Sites

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, J. -J. [Argonne National Lab. (ANL), Argonne, IL (United States); Chang, Y. -S. [Argonne National Lab. (ANL), Argonne, IL (United States); Hartmann, H. [Argonne National Lab. (ANL), Argonne, IL (United States); Wescott, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Kygeris, C. [Indiana Univ. of Pennsylvania, PA (United States)

    2013-09-01

    This report presents a general methodology for obtaining preliminary estimates of the potential human health risks associated with developing a utility-scale solar energy facility on a contaminated site, based on potential exposures to contaminants in soils (including transport of those contaminants into the air).

  4. Study of surface potential contamination in radioisotope and radiopharmaceutical production facilities and alternative solutions

    International Nuclear Information System (INIS)

    Suhaedi Muhammad; Rimin Sumantri; Farida Tusafariah; Djarwanti Rahayu Pipin Soedjarwo

    2013-01-01

    Radioisotope and radiopharmaceutical production facilities that exist in their operations around the world in the form of radiological impacts of radiation exposure, contamination of surface and air contamination. Given the number of existing open source in radioisotope and radiopharmaceutical production facility, then the possibility of surface contamination in the work area is quite high. For that to protect the safety and health of both workers, the public and the environment, then the licensee must conduct an inventory of some of the potential that could result in contamination of surfaces in radioisotope and radiopharmaceutical production facilities. Several potential to cause surface contamination in radioisotope and radiopharmaceutical production facilities consist of loss of resources, the VAC system disorders, impaired production facilities, limited resources and lack of work discipline and radioactive waste handling activities. From the study of some potential, there are several alternative solutions that can be implemented by the licensee to address the contamination of the surface so as not to cause adverse radiological impacts for both radiation workers, the public or the environment. (author)

  5. Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants

    International Nuclear Information System (INIS)

    Suter, G.W. II; Will, M.E.; Evans, C.

    1993-09-01

    One of the initial stages in ecological risk assessment for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as ''contaminants of potential concern.'' This process is termed ''contaminant screening.'' It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 34 chemicals potentially associated with US Department of Energy (DOE) sites. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern. The purpose of this report is to present plant toxicity data and discuss their utility as benchmarks for determining the hazard to terrestrial plants caused by contaminants in soil. Benchmarks are provided for soils and solutions

  6. Widespread occurrence and potential for biodegradation of bioactive contaminants in Congaree National Park, USA

    Science.gov (United States)

    Bradley, Paul M.; Battaglin, William A.; Clark, Jimmy M.; Henning, Frank; Hladik, Michelle L.; Iwanowicz, Luke R.; Journey, Celeste A.; Riley, Jeffrey W.; Romanok, Kristin

    2017-01-01

    Organic contaminants with designed molecular bioactivity, such as pesticides and pharmaceuticals, originate from human and agricultural sources, occur frequently in surface waters, and threaten the structure and function of aquatic and terrestrial ecosystems. Congaree National Park in South Carolina (USA) is a vulnerable park unit due to its location downstream of multiple urban and agricultural contaminant sources and its hydrologic setting, being composed almost entirely of floodplain and aquatic environments. Seventy-two water and sediment samples were collected from 16 sites in Congaree National Park during 2013 to 2015, and analyzed for 199 and 81 targeted organic contaminants, respectively. More than half of these water and sediment analytes were not detected or potentially had natural sources. Pharmaceutical contaminants were detected (49 total) frequently in water throughout Congaree National Park, with higher detection frequencies and concentrations at Congaree and Wateree River sites, downstream from major urban areas. Forty-seven organic wastewater indicator chemicals were detected in water, and 36 were detected in sediment, of which approximately half are distinctly anthropogenic. Endogenous sterols and hormones, which may originate from humans or wildlife, were detected in water and sediment samples throughout Congaree National Park, but synthetic hormones were detected only once, suggesting a comparatively low risk of adverse impacts. Assessment of the biodegradation potentials of 8 14C-radiolabeled model contaminants indicated poor potentials for some contaminants, particularly under anaerobic sediments conditions.

  7. Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Suter, G.W. II; Will, M.E.; Evans, C.

    1993-09-01

    One of the initial stages in ecological risk assessment for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as ``contaminants of potential concern.`` This process is termed ``contaminant screening.`` It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 34 chemicals potentially associated with US Department of Energy (DOE) sites. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern. The purpose of this report is to present plant toxicity data and discuss their utility as benchmarks for determining the hazard to terrestrial plants caused by contaminants in soil. Benchmarks are provided for soils and solutions.

  8. Bioindicating potential of strontium contamination with Spanish moss Tillandsia usneoides

    International Nuclear Information System (INIS)

    Zheng, Guiling; Pemberton, Robert; Li, Peng

    2016-01-01

    Tillandsia species have been recognized as efficient biomonitors of air pollution, but rarely exploited in bioindicating of strontium, an important nuclide. We exposed Tillandsia usneoides, colloquially known as Spanish moss due to its filamentous morphology but is an atypical angiosperm in the family Bromeliaceae, to the solutions with different Sr concentrations (0.1–100 mmol/L). The results showed that plants were able to endure Sr stress for a relatively long period, which suggests that T. usneoides is able to resist this toxic element. T. usneoides had the highest uptake ratio of Sr (82.21 ± 0.12%) when the plants were exposed to 0.1 mmol/L Sr solutions. Sr contents in T. usneoides increased significantly with the increase in applied metal solution concentrations. Low Sr stimulated the formation of chlorophyll, but high Sr decreased the contents of chlorophyll, and no significant effect on the total biomass was found in T. usneoides. In contrast, the permeability of plasma membrane based on the relative electronic conductivity in T. usneoides increased significantly under Sr stress, indicating that Sr probably caused oxidative stress. Moreover, correlation analysis showed that the leaf relative conductivity was significantly positively correlated with Sr contents in the plants after Sr treatments. Therefore, T. usneoides has considerable potential for monitoring Sr polluted environments through measuring Sr contents in the plant directly or exploiting the leaf relative conductivity as an indirect biomarker. - Highlights: • Sr contents in T. usneoides increase significantly with the increase of Sr concentrations. • Leaf relative conductivity is significantly positively correlated with Sr contents in the plant. • Tillandsia has high potential for monitoring Sr.

  9. Metagenomic Functional Potential Predicts Degradation Rates of a Model Organophosphorus Xenobiotic in Pesticide Contaminated Soils

    Directory of Open Access Journals (Sweden)

    Thomas C. Jeffries

    2018-02-01

    Full Text Available Chemical contamination of natural and agricultural habitats is an increasing global problem and a major threat to sustainability and human health. Organophosphorus (OP compounds are one major class of contaminant and can undergo microbial degradation, however, no studies have applied system-wide ecogenomic tools to investigate OP degradation or use metagenomics to understand the underlying mechanisms of biodegradation in situ and predict degradation potential. Thus, there is a lack of knowledge regarding the functional genes and genomic potential underpinning degradation and community responses to contamination. Here we address this knowledge gap by performing shotgun sequencing of community DNA from agricultural soils with a history of pesticide usage and profiling shifts in functional genes and microbial taxa abundance. Our results showed two distinct groups of soils defined by differing functional and taxonomic profiles. Degradation assays suggested that these groups corresponded to the organophosphorus degradation potential of soils, with the fastest degrading community being defined by increases in transport and nutrient cycling pathways and enzymes potentially involved in phosphorus metabolism. This was against a backdrop of taxonomic community shifts potentially related to contamination adaptation and reflecting the legacy of exposure. Overall our results highlight the value of using holistic system-wide metagenomic approaches as a tool to predict microbial degradation in the context of the ecology of contaminated habitats.

  10. Potential radiation dose from eating fish exposed to actinide contamination

    International Nuclear Information System (INIS)

    Emery, R.M.; Klopfer, D.C.; Baker, D.A.; Soldat, J.K.

    1980-01-01

    The purpose of this work is to establish a maximum potential for transporting actinides to man via fish consumption. The study took place in U-Pond, a nuclear waste pond on the Hanford Site. It has concentrations of 238 U, 238 Pu, /sup 239,240/Pu and 241 Am that are approximately three orders of magnitude greater than background levels. Fish living in the pond contain higher actinide concentrations than those observed in fish from any other location. Experiments were performed in U-pond to determine maximum quantities of actinides that could accumulate in fillets and whole bodies of two centrarchid fish species. Doses to hypothetical consumers were then estimated by assuming that actinide behavior in their bodies was similar to that defined for Standard Man by the International Commission on Radiological Protection. Results indicate that highest concentrations occurring in bluegill or bass muscle after more than a year's exposure to the pond would not be sufficient to produce a significant radiation dose to a human consumer, even if he ate 0.5 kg (∼1 lb) of these fillets every day for 70 years. Natural predators (heron or coyote), having lifetime diets of whole fish from U-Pond, would receive less radiation dose from the ingested actinides than from natural background sources. 34 refs., 5 figs., 4 tabs

  11. Potential radiation dose from eating fish exposed to actinide contamination

    International Nuclear Information System (INIS)

    Emery, R.M.; Klopfer, D.C.; Baker, D.A.; Soldat, J.K.

    1981-01-01

    The purpose of this work is to establish a maximum potential for transporting actinides to man via fish consumption. The study took place in U-pond, a nuclear waste pond on the Hanford Site. It has concentrations of 238 U, 238 Pu, sup(239,240)Pu and 241 Am that are approx. 3 orders of magnitude greater than background levels. Fish living in the pond contain higher actinide concentrations than those observed in fish from any other location. Experiments were performed in U-Pond to determine maximum quantities of actinides that could accumulate in fillets and whole bodies of two centrarchid fish species. Doses to hypothetical consumers were then estimated. Results indicate that highest concentrations occurring in bluegill or bass muscle after more than a year's exposure to the pond would not be sufficient to produce a significant radiation dose to a human consumer, even if he ate 0.5 kg (of the order of 1 lb) of these fillets every day for 70 yr. Natural predators (heron or coyote), having lifetime diets of whole fish from U-Pond, would receive less radiation dose from the ingested actinides than from natural background sources. (author)

  12. Bioindicating potential of strontium contamination with Spanish moss Tillandsia usneoides.

    Science.gov (United States)

    Zheng, Guiling; Pemberton, Robert; Li, Peng

    2016-02-01

    Tillandsia species have been recognized as efficient biomonitors of air pollution, but rarely exploited in bioindicating of strontium, an important nuclide. We exposed Tillandsia usneoides, colloquially known as Spanish moss due to its filamentous morphology but is an atypical angiosperm in the family Bromeliaceae, to the solutions with different Sr concentrations (0.1-100 mmol/L). The results showed that plants were able to endure Sr stress for a relatively long period, which suggests that T. usneoides is able to resist this toxic element. T. usneoides had the highest uptake ratio of Sr (82.21 ± 0.12%) when the plants were exposed to 0.1 mmol/L Sr solutions. Sr contents in T. usneoides increased significantly with the increase in applied metal solution concentrations. Low Sr stimulated the formation of chlorophyll, but high Sr decreased the contents of chlorophyll, and no significant effect on the total biomass was found in T. usneoides. In contrast, the permeability of plasma membrane based on the relative electronic conductivity in T. usneoides increased significantly under Sr stress, indicating that Sr probably caused oxidative stress. Moreover, correlation analysis showed that the leaf relative conductivity was significantly positively correlated with Sr contents in the plants after Sr treatments. Therefore, T. usneoides has considerable potential for monitoring Sr polluted environments through measuring Sr contents in the plant directly or exploiting the leaf relative conductivity as an indirect biomarker. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Utilization of grasses for potential biofuel production and phytoremediation of heavy metal contaminated soils.

    Science.gov (United States)

    Balsamo, Ronald A; Kelly, William J; Satrio, Justinus A; Ruiz-Felix, M Nydia; Fetterman, Marisa; Wynn, Rodd; Hagel, Kristen

    2015-01-01

    This research focuses on investigating the use of common biofuel grasses to assess their potential as agents of long-term remediation of contaminated soils using lead as a model heavy metal ion. We present evidence demonstrating that switch grass and Timothy grass may be potentially useful for long-term phytoremediation of heavy metal contaminated soils and describe novel techniques to track and remove contaminants from inception to useful product. Enzymatic digestion and thermochemical approaches are being used to convert this lignocellulosic feedstock into useful product (sugars, ethanol, biocrude oil+biochar). Preliminary studies on enzymatic hydrolysis and fast pyrolysis of the Switchgrass materials that were grown in heavy metal contaminated soil and non-contaminated soils show that the presence of lead in the Switchgrass material feedstock does not adversely affect the outcomes of the conversion processes. These results indicate that the modest levels of contaminant uptake allow these grass species to serve as phytoremediation agents as well as feedstocks for biofuel production in areas degraded by industrial pollution.

  14. Glyphosate: environmental contamination, toxicity and potential risks to human health via food contamination.

    Science.gov (United States)

    Bai, Shahla Hosseini; Ogbourne, Steven M

    2016-10-01

    Glyphosate has been the most widely used herbicide during the past three decades. The US Environmental Protection Agency (EPA) classifies glyphosate as 'practically non-toxic and not an irritant' under the acute toxicity classification system. This classification is based primarily on toxicity data and due to its unique mode of action via a biochemical pathway that only exists in a small number of organisms that utilise the shikimic acid pathway to produce amino acids, most of which are green plants. This classification is supported by the majority of scientific literature on the toxic effects of glyphosate. However, in 2005, the Food and Agriculture Organisation (FAO) reported that glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), are of potential toxicological concern, mainly as a result of accumulation of residues in the food chain. The FAO further states that the dietary risk of glyphosate and AMPA is unlikely if the maximum daily intake of 1 mg kg(-1) body weight (bw) is not exceeded. Research has now established that glyphosate can persist in the environment, and therefore, assessments of the health risks associated with glyphosate are more complicated than suggested by acute toxicity data that relate primarily to accidental high-rate exposure. We have used recent literature to assess the possible risks associated with the presence of glyphosate residues in food and the environment.

  15. Evaluation of heavy metals transfer: impact of a dredged sediment deposit on a on-polluted soil; Migration des polluants metalliques: cas d'un depot de sediments contamines sur un sol non pollue

    Energy Technology Data Exchange (ETDEWEB)

    Vauleon, C.; Laboudigue, A. [Centre National de Recherche sur les Sites et Sols Pollues, CNRSSP, 59 - Douai (France); Tiffreau, Ch. [CEA Cadarache, 13 - Saint Paul lez Durance (France)

    2001-07-01

    In many countries and especially in the North of France, inland waterways need to be dredged regularly to provide a high quality environment for customers, staff and local communities. However, dredging operations generate yearly large quantities of sediments, which in spite of their high pollutant contents, are often stored in non-specific sites. Thus, the threat of a spreading contamination for the surrounding environment is important. In order to evaluate this potential risk and to quantify the transfer of heavy metals from the dredged layer to the non-polluted soil below, an interdisciplinary research project was undertaken including, (i) the monitoring of an experimental sediment deposit, (ii) the microscopic study of metal distribution inside this deposit, (iii) the evaluation of microbial activity, (iv) the impact of natural vegetation growth on metal migration. Up to now, the main processes identified (oxidation of sulphur compounds, vertical migration of Zinc) allowed us to make several recommendations for the future management of dredged sediments by: (i) controlling the oxidation processes during dredging operations or (ii) assessing the high neutralizing capacity of the local environment of deposition. Moreover, an adequate vegetation management can reduce the heavy metals migration to groundwater's with maximum efficiency and at low costs. (author)

  16. Sources, migration and transformation of antimony contamination in the water environment of Xikuangshan, China: Evidence from geochemical and stable isotope (S, Sr) signatures

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Bing [Geological Survey, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); Zhou, Jianwei, E-mail: jw.zhou@cug.edu.cn [School of Environmental Studies, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); Zhou, Aiguo; Liu, Cunfu [School of Environmental Studies, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); Xie, Lina [School of Environmental Studies, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China)

    2016-11-01

    The Xikuangshan (XKS) mine in central China is the largest antimony (Sb) mine in the world. The mining activity has seriously contaminated the waters in the area. To determine the sources, migration and transformation of Sb contamination, 32 samples from groundwater (aquifer water), surface water and mine water were collected for water chemistry, trace element and S{sub SO4} and Sr stable isotope analyses. The results showed that the groundwater and surface water were in an oxidized environment. The S{sub SO4} and Sr isotope compositions in the water indicated that dissolved Sb and SO{sub 4}{sup 2} originated from sulfide mineral (Sb{sub 2}S{sub 3}) oxidation, whereas radiogenic Sr may have been sourced from silicified limestone and stibnite in the Shetianqiao aquifer. Furthermore, a positive correlation between δ{sup 34}S{sub SO4} and δ{sup 87}Sr values revealed that the Sr, S and Sb in the waters had a common contamination source, i.e., silicified limestone and stibnite, whereas the Sr, S and Sb in rock and ore were sourced from Proterozoic basement clastics. The analysis also indicated that the isotope composition of dissolved SO{sub 4}{sup 2} {sup −} had been influenced by slight bacterial SO{sub 4} reduction in the Magunao aquifer. Mining or rock collapse may have caused Shetianqiao aquifer water to contaminate the Magunao aquifer water via mixing. This study has demonstrated that the stable isotopes of {sup 34}S{sub SO4} and {sup 87}Sr, combined with hydrochemical methods, are effective in tracking the sources, migration and transformation of Sb contamination. - Highlights: • Mining activities at XKS mine have caused serious water contamination. • The characteristics of Sb contamination in water environment are still unclear. • Combine S isotopes of sulfate and Sr isotopes with hydrochemical methods. • Sr, S, and Sb in natural water had a common source: silicified limestone and stibnite. • Shetianqiao aquifer water contaminated the Magunao

  17. Combination of bioleaching by gross bacterial biosurfactants and flocculation: A potential remediation for the heavy metal contaminated soils.

    Science.gov (United States)

    Yang, Zhihui; Shi, Wei; Yang, Weichun; Liang, Lifen; Yao, Wenbin; Chai, Liyuan; Gao, Shikang; Liao, Qi

    2018-09-01

    Combining bioleaching by the gross biosurfactants of Burkholderia sp. Z-90 and flocculation by poly aluminium chloride (PAC) was proposed to develop a potential environment-friendly and cost-effective technique to remediate the severely contaminated soils by heavy metals. The factors affecting soil bioleaching by the gross biosurfactants of Burkholderia sp. Z-90 were optimized. The results showed the optimal removing efficiencies of Zn, Pb, Mn, Cd, Cu, and As by the Burkholderia sp. Z-90 leachate were 44.0, 32.5, 52.2, 37.7, 24.1 and 31.6%, respectively at soil liquid ratio of 1:20 (w/v) for 5 d, which were more efficient than that by 0.1% of rhamnolipid. The amounts of the bioleached heavy metals by the Burkholderia sp. Z-90 leachate were higher than that by other biosurfactants in the previous studies, although the removal efficiencies of the metals by the leachate were relatively lower. It was suggested that more heavy metals caused more competitive to chelate with function groups of the gross biosurfactants and the metal removal efficiencies by biosurfactants in natural soils were lower than in the artificially contaminated soils. Moreover, the Burkholderia sp. Z-90 leachate facilitated the metals to be transformed to the easily migrating speciation fractions. Additional, the results showed that PAC was efficient in the following flocculation to remove heavy metals in the waste bio-leachates. Our study will provide support for developing a bioleaching technique model to remediate the soils extremely contaminated by heavy metals. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Many routes leading to Rome: Potential causes for the multi-route migration system of Red Knots Calidris canutus islandica

    NARCIS (Netherlands)

    Bauer, S.; Ens, B.J.; Klaassen, M.R.J.

    2010-01-01

    Migrants, such as birds or representatives of other taxa, usually make use of several stopover sites to cover the distance between their site of origin and destination. Potentially, multiple routes exist, but often little is known about the causes and consequences of alternative migration routes.

  19. Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants: 1994 revision

    International Nuclear Information System (INIS)

    Will, M.E.; Suter, G.W. II.

    1994-09-01

    One of the initial stages in ecological risk assessment for hazardous waste sites is screening contaminants to determine which of them are worthy of further consideration as contaminants of potential concern. This process is termed contaminant screening. It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 38 chemicals potentially associated with United States Department of Energy (DOE) sites. In addition, background information on the phytotoxicity and occurrence of the chemicals in soils is presented, and literature describing the experiments from which data were drawn for benchmark derivation is reviewed. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern

  20. Toxicological benchmarks for screening potential contaminants of concern for effects on terrestrial plants: 1994 revision

    Energy Technology Data Exchange (ETDEWEB)

    Will, M.E.; Suter, G.W. II

    1994-09-01

    One of the initial stages in ecological risk assessment for hazardous waste sites is screening contaminants to determine which of them are worthy of further consideration as contaminants of potential concern. This process is termed contaminant screening. It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 38 chemicals potentially associated with United States Department of Energy (DOE) sites. In addition, background information on the phytotoxicity and occurrence of the chemicals in soils is presented, and literature describing the experiments from which data were drawn for benchmark derivation is reviewed. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern.

  1. Toxicological Benchmarks for Screening Potential Contaminants of Concern for Effects on Terrestrial Plants

    Energy Technology Data Exchange (ETDEWEB)

    Suter, G.W. II

    1993-01-01

    One of the initial stages in ecological risk assessment for hazardous waste sites is screening contaminants to determine which of them are worthy of further consideration as contaminants of potential concern. This process is termed contaminant screening. It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 38 chemicals potentially associated with United States Department of Energy (DOE) sites. In addition, background information on the phytotoxicity and occurrence of the chemicals in soils is presented, and literature describing the experiments from which data were drawn for benchmark derivation is reviewed. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern.

  2. Reproductive potential of silver European eels (Anguilla anguilla migrating from Vistonis Lake (Northern Aegean Sea, Greece

    Directory of Open Access Journals (Sweden)

    R. MACNAMARA

    2014-06-01

    Full Text Available The European eel (Anguilla anguilla, once abundant throughout much of Europe and North Africa, has recently been classified as critically endangered. Information on its biology from the eastern Mediterranean is lacking, especially in relation to spawner quality. Therefore, silver eels were sampled during their seaward spawning migration from Vistonis Lake in Greece. Characteristics linked to reproductive output and success (i.e. body size and condition, sex ratio, silvering, Anguillicola crassus infection, fecundity and oocyte diameter were examined. The lake produced large (687–1138 mm, exclusively female silver eels, 61.7% of which were infected by A. crassus. Silver eel fecundity, the first estimates from the southern part of the species range, was positively related to body length (R2 = 0.693; P < 0.001 and body weight (R2 = 0.731; P < 0.001. Fecundity did not differ between A. crassus infected and uninfected silver eels, but Greek silver eels were significantly more fecund than those in north-west Europe. The reproductive potential of Vistonis Lake silver eels and their contribution to the A. anguilla spawning stock is discussed.

  3. Determination of heavy metal pollution in soils from selected potentially contaminated sites in Tema

    International Nuclear Information System (INIS)

    Nyaaba, A.K.L.

    2011-01-01

    The objective of the study was to assess the concentration and determine the level of pollution by harmful heavy metals in soils from selected potentially contaminated sites in Tema. The metals of interest include; mercury, lead, cadmium, cobalt zinc, arsenic, nickel, copper and chromium. A total of forty seven (47) samples comprising thirty eight sub-samples (38) and nine (9) composite samples were collected from nine (9) different locations. These included playgrounds, steel processing factories, used Lead Acid Battery (ULAB) recycling plant, mechanic workshops and the municipal waste disposal site. The samples were prepared after which the elemental concentrations were determined using energy dispersive X-ray fluorescence (EDXRF) with a secondary target excitation arrangement (5.9 keV). The analysis of the samples yielded the following mean heavy metal concentrations in mg/kg: 424.38 (Cr); 408.68 (Ni); 14427 (Cu); 4129.87 (Zn); 1580.68 (As); 647.48 (Hg); 73361.51 (Pb) and 1176.16 (Co). The mean concentrations of heavy metals in the soils were in the following order Pb>Zn>As>Co>Cu>Hg>Cr>Ni. Mercury was detected at only two of the sites. The average heavy metals in the soils from the sites were generally high since most of them exceeded the optimum and action values of the New Dutch List. The Enrichment Factor (EF) ratios show that the enrichment of the elements in the soils ranged from deficiently to extremely highly enriched. The contamination factor show that the contamination by the heavy metals were low at some of the sites and very high at others. The geoaccumulation indices indicated that the playground (PG) has not been contaminated by any of the metals, C8 is contaminated strongly by mercury only and the contamination at the remaining sites varied from moderately contaminated to extremely contaminated by the metals. The Igeo also indicated that the elements accounting for extreme contamination are lead, arsenic, copper, zinc mercury and chromium. Lead

  4. Hydrographic features of anguillid spawning areas: Potential signposts for migrating eels

    DEFF Research Database (Denmark)

    Schabetsberger, Robert; Miller, Michael J.; Dall'Olmo, Giorgio

    2016-01-01

    Catadromous anguillid eels (genus Anguilla) migrate from their freshwater or estuarine habitats to marine spawning areas. Evidence from satellite tagging studies indicates that tropical and temperate eel species exhibit pronounced diel vertical migrations, from between 150-300 m nighttime depths...... to 600-800 m during the day. Collections of eggs and larvae of Japanese eels A. japonica suggest they may spawn at these upper nighttime migration depths. How anguillid eels navigate through the ocean and find their spawning areas remains unknown; thus, this study describes the salinity, temperature...

  5. Detection of microbial contaminations in drinking water using ATP measurements – evaluating potential for online monitoring

    DEFF Research Database (Denmark)

    Vang, Óluva Karin; Corfitzen, Charlotte B.; Albrechtsen, Hans-Jørgen

    2011-01-01

    There is an increasing call for fast and reliable methods for continuous monitoring of microbial drinking water quality in order to protect public health. The potential for Adenosine triphosphate (ATP) measurements as a real-time analysis for continuous monitoring of microbial drinking water...... quality was investigated through simulation of two contamination scenarios, i.e. drinking water contaminated with waste water and surface water at various concentrations. With ATP measurements it was possible to detect waste water diluted 1000-10,000 times in drinking water depending on sensitivity...... of reagent kit. Surface water diluted 100-1000 times was detected in drinking water with ATP measurements. ATP has the potential as an early warning tool, especially in the period when the contamination concentration is high. 2011 © American Water Works Association AWWA WQTC Conference Proceedings All Rights...

  6. A study on migration of contaminants and effect on the groundwater system at the Gemencheh domestic waste disposal site, Negeri Sembilan using integrated nuclear, geophysical and hydrogeochemical methods

    International Nuclear Information System (INIS)

    Mohd Tadza Abdul Rahman

    2001-01-01

    The domestic waste disposal site at Gemencheh, Negeri Sembilan has been in operation since 1981. Integration of three methods namely nuclear, geophysical and hydrogeochemical were used to study the migration and effects of contaminants on the groundwater system at this particular site. Nuclear method was used to determine groundwater system flow velocity that delineates the migration pattern of contaminant species in the groundwater system at the study area. The groundwater flow velocity is found to be heterogeneous and depend on hydraulic conductivity caused by soil permeability except in the low-lying downstream area where the flow velocity is found to be low and constant at 2.0 x 10 -6 ms -1 . However, the flow velocity increases to as high as 17.8 x 10 -5 ms -1 during rainy season due to the influence of weather on hydraulic gradient. Weather condition also influences the flow direction, whereby during draught season, the groundwater flow direction at the middle of the study site moves from an area of high topography to the northeast and southeast of low topography areas. On the other hand, at the downstream the groundwater flows partially towards northeast and southeast whereas flow direction at the upstream is towards the east. A similar pattern was observed during rainy season in both upstream and downstream of the study site but at the middle, the flow is basically towards south-east with a side flow to the north-east and east direction. Geophysical method comprising geo electrical-imaging and electromagnetic transient techniques was used to determine the extent, depth and distribution of contamination in the groundwater system. This method shows that the most seriously contaminated areas at the middle and the downstream regions of the study site within the shallow depth of 3-6 metres. The distribution of the contaminants in groundwater is not widespread but confined within the study site only. Finally, hydrogeochemical method was used to determine the

  7. 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.

  8. Plants Rather than Mineral Fertilization Shape Microbial Community Structure and Functional Potential in Legacy Contaminated Soil

    Czech Academy of Sciences Publication Activity Database

    Rídl, Jakub; Kolář, Michal; Strejček, M.; Strnad, Hynek; Štursa, P.; Pačes, Jan; Macek, T.; Uhlík, O.

    2016-01-01

    Roč. 7, JUN 24 (2016), č. článku 995. ISSN 1664-302X R&D Projects: GA ČR GA13-28283S Institutional support: RVO:68378050 Keywords : microbial community structure * plants * fertilization * contaminated soil * functional potential Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.076, year: 2016

  9. HOLISTIC APPROACH FOR ASSESSING THE PRESENCE AND POTENTIAL IMPACTS OF WATERBORNE ENVIRONMENTAL CONTAMINANTS

    Science.gov (United States)

    As an integral part of our continuing research in environmental quality assessment approaches, we have developed a variety of passive integrative sampling devices widely applicable for use in defining the presence and potential impacts of a broad array of contaminants. The semipe...

  10. Methodological guide: management of industrial sites potentially contaminated by radioactive substances

    International Nuclear Information System (INIS)

    2001-01-01

    At the request of the Ministries of Health and the Environment, IPSN is preparing and publishing the first version of the methodological guide devoted to managing industrial sites potentially contaminated by radioactive substances. This guide describes a procedure for defining and choosing strategies for rehabilitating such industrial sites. (author)

  11. Widespread occurrence and potential for biodegradation of bioactive contaminants in Congaree National Park, USA.

    Science.gov (United States)

    Bradley, Paul M; Battaglin, William A; Clark, Jimmy M; Henning, Frank P; Hladik, Michelle L; Iwanowicz, Luke R; Journey, Celeste A; Riley, Jeffrey W; Romanok, Kristin M

    2017-11-01

    Organic contaminants with designed molecular bioactivity, such as pesticides and pharmaceuticals, originate from human and agricultural sources, occur frequently in surface waters, and threaten the structure and function of aquatic and terrestrial ecosystems. Congaree National Park in South Carolina (USA) is a vulnerable park unit due to its location downstream of multiple urban and agricultural contaminant sources and its hydrologic setting, being composed almost entirely of floodplain and aquatic environments. Seventy-two water and sediment samples were collected from 16 sites in Congaree National Park during 2013 to 2015, and analyzed for 199 and 81 targeted organic contaminants, respectively. More than half of these water and sediment analytes were not detected or potentially had natural sources. Pharmaceutical contaminants were detected (49 total) frequently in water throughout Congaree National Park, with higher detection frequencies and concentrations at Congaree and Wateree River sites, downstream from major urban areas. Forty-seven organic wastewater indicator chemicals were detected in water, and 36 were detected in sediment, of which approximately half are distinctly anthropogenic. Endogenous sterols and hormones, which may originate from humans or wildlife, were detected in water and sediment samples throughout Congaree National Park, but synthetic hormones were detected only once, suggesting a comparatively low risk of adverse impacts. Assessment of the biodegradation potentials of 8 14 C-radiolabeled model contaminants indicated poor potentials for some contaminants, particularly under anaerobic sediments conditions. Environ Toxicol Chem 2017;36:3045-3056. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. © 2017 SETAC.

  12. Assessing potential impacts associated with contamination events in water distribution systems : a sensitivity analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Davis, M. J.; Janke, R.; Taxon, T. N. (Decision and Information Sciences); ( EVS); (EPA)

    2010-11-01

    An understanding of the nature of the adverse effects that could be associated with contamination events in water distribution systems is necessary for carrying out vulnerability analyses and designing contamination warning systems. This study examines the adverse effects of contamination events using models for 12 actual water systems that serve populations ranging from about 104 to over 106 persons. The measure of adverse effects that we use is the number of people who are exposed to a contaminant above some dose level due to ingestion of contaminated tap water. For this study the number of such people defines the impact associated with an event. We consider a wide range of dose levels in order to accommodate a wide range of potential contaminants. For a particular contaminant, dose level can be related to a health effects level. For example, a dose level could correspond to the median lethal dose, i.e., the dose that would be fatal to 50% of the exposed population. Highly toxic contaminants may be associated with a particular response at a very low dose level, whereas contaminants with low toxicity may only be associated with the same response at a much higher dose level. This report focuses on the sensitivity of impacts to five factors that either define the nature of a contamination event or involve assumptions that are used in assessing exposure to the contaminant: (1) duration of contaminant injection, (2) time of contaminant injection, (3) quantity or mass of contaminant injected, (4) population distribution in the water distribution system, and (5) the ingestion pattern of the potentially exposed population. For each of these factors, the sensitivities of impacts to injection location and contaminant toxicity are also examined. For all the factors considered, sensitivity tends to increase with dose level (i.e., decreasing toxicity) of the contaminant, with considerable inter-network variability. With the exception of the population distribution (factor 4

  13. Assessment of toxic and endocrine potential of substances migrating from selected toys and baby products.

    Science.gov (United States)

    Szczepańska, Natalia; Namieśnik, Jacek; Kudłak, Błażej

    2016-12-01

    Analysis of literature data shows that there is limited information about the harmful biological effects of mixture of compounds from the EDC group that are released from the surface of toys and objects intended for children and infants. One of the tools that can be used to obtain such information is appropriate bioanalytical tests. The aim of this research involved determining whether tests that use living organisms as an active element (Vibrio fischeri-Microtox®, Heterocypris incongruens-Ostrocodtoxkit F™ and the XenoScreen YES/YAS™ test of oestrogenic/androgenic activity) can be a tool for estimating the combined toxic effects induced by xenobiotics released from objects intended for children. To reproduce the conditions to which objects are exposed during their use, liquids with a composition corresponding to that of human bodily fluids (artificial sweat and saliva) were used. This research focused on the main parameters influencing the intensification of the migration process (temperature, contact time and composition of the extraction mixture). The studies aimed to estimate the endocrine potential of the extracts showed that compounds released from the surface of studied objects exhibit antagonistic androgenic activity. While on the basis of the results of Microtox® test, one can state that the largest quantity of toxic compounds are released in the first 2 h of using the object. The FTIR spectra analyses confirmed that no degradation of polymeric material took place. On the basis of the results obtained, it was unanimously concluded that contact of the object with bodily fluids may result in the release of a large number of xenobiotics, which has disadvantageous effects on the metabolic processes of the indicator organisms.

  14. Assessing the potential of brachiaria decumbens as remediation agent for soil contaminated wit oil sludge

    International Nuclear Information System (INIS)

    Latiffah Norddin; Ahmad Nazrul Abd Wahid; Hazlina Abdullah; Abdul Razak Ruslan

    2005-01-01

    Bioremediation is a method of treatment of soil or water contaminated with toxic materials, involving the use of living organisms. Oil or petroleum sludge is a waste product of the petroleum refining industry, and is now accumulating at a fast rate at petroleum refinery sites in the country. Common components of oil sludge are mud and sand, containing toxic materials from hydrocarbons, heavy metals and radioactive elements from the seabed. In the present study, the oil sludge samples were obtained from barrels of the materials stored at the Radioactive Waste Treatment Centre, MINT. The samples were analysed of their compounds, elemental and radioactive contents. Trials on microbial degradation of the sludge materials were ongoing. This paper discusses the potential of a grass to remediate soils contaminated with petroleum sludge. Remediation of soils contaminated with organic compounds and heavy metals using plants, including grasses, including Vetiver, Lolium and Agrostis have been carried out in many countries. A greenhouse pot trial was conducted to assess the suitability of the pasture grass Brachiaria decumbens Stapf. and its mutant Brachiaria decumbens KLUANG Comel as a remediation agent for oil sludge contaminated soil. Samples of grasses and soils before planting, during growth stage and at end of experiment were analysed for the different toxicity. Although the grasses were promoted for use in pasture, and KLUANG Comel has good potential as an ornamental plant, too, their other potentials, including as phytoremediation agents need to be explored. (Author)

  15. Sporulation of Bacillus spp. within biofilms: a potential source of contamination in food processing environments.

    Science.gov (United States)

    Faille, C; Bénézech, T; Midelet-Bourdin, G; Lequette, Y; Clarisse, M; Ronse, G; Ronse, A; Slomianny, C

    2014-06-01

    Bacillus strains are often isolated from biofilms in the food industries. Previous works have demonstrated that sporulation could occur in biofilms, suggesting that biofilms would be a significant source of food contamination with spores. In this study, we investigated the properties of mono-species and mixed Bacillus biofilms and the ability of Bacillus strains to sporulate inside biofilms. Bacillus strains were able to form mono-species biofilms on stainless steel coupons, with up to 90% spores after a 48 h-incubation. These spores were highly resistant to cleaning but were easily transferred to agar, mimicking the cross-contamination of food, thereby suggesting that biofilms would be of particular concern due to a potential for Bacillus spore food contamination. This hypothesis was strengthened by the fact that Bacillus strains were able to form mixed biofilms with resident strains and that sporulation still occurred easily in these complex structures. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Identifying potential sources of Sudan I contamination in Capsicum fruits over its growth period.

    Science.gov (United States)

    Wu, Naiying; Gao, Wei; Zhou, Li; Lian, Yunhe; Li, Fengfei; Han, Wenjie

    2015-04-15

    Sudan dyes in spices are often assumed to arise from cross-contamination or malicious addition. Here, experiments were carried out to identify the potential source of Sudan I-IV in Capsicum fruits through investigation of their contents in native Capsicum tissues, soils and associated agronomic materials. Sudan II-IV was not detected in any of the tested samples. Sudan I was found in almost all samples except for the mulching film. Sudan I concentrations decreased from stems to leaves and then to fruits or roots. Sudan I levels in soils were significantly elevated by vegetation treatment. These results exclude the possibility of soil as the main source for Sudan I contamination in Capsicum fruits. Further study found out pesticide and fertilizer constitutes the major source of Sudan I contamination. This work represents a preliminary step for a detailed Sudan I assessment to support Capsicum management and protection in the studied region. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Dendritic cell migration assay: a potential prediction model for identification of contact allergens.

    Science.gov (United States)

    Gibbs, Susan; Spiekstra, Sander; Corsini, Emanuela; McLeod, Julie; Reinders, Judith

    2013-04-01

    This manuscript describes methodology and a prediction model for the MUTZ-LC migration assay. The assay represents the physiological change in Langerhans cell (LC) behavior after exposure to a sensitizing chemical, resulting in LC migration from the epidermis to the dermis. MUTZ-LC are derived from the commercially available MUTZ-3 cell line. Upon exposure to a sensitizer MUTZ-LC migrate preferentially towards CXCL12 whereas upon exposure to a non-sensitizer MUTZ-LC migrate towards CCL5. A CXCL12/CCL5 ratio >1.10 in 2/3 independent experiments is indicative of a sensitizer, whereas a CXCL12/CCL5 ratio ≤1.10 is indicative of a non-sensitizer. At non cytotoxic chemical concentrations 9 sensitizers (2,4-dinitrochlorobenzene, paraphenylendiamine, cinnamaldehyde, isoeugenol, nickel-sulfate, tetramethylthiuram disulfide, eugenol, cinnamic-alcohol, ammonium-hexachloroplatinate) were distinguished from 4 non sensitizers (sodium lauryl sulfate, salicylic acid, phenol, octanoic acid). Critical points in assay performance are (i) MUTZ-3 passage number after thawing (p6-p40); (ii) cell viability (>80%); (iii) standard curve to optimize correlation of fluorescence with cell number; and (iv) optimization of the concentration of rhCXCL12 and rhCCL5 in transwell. The protocol has been tested in three European laboratories and results suggest that it may provide working conditions for performing the DC migration assay which is aimed at distinguishing sensitizers from non sensitizers. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Healthcare workers mobile phone usage: A potential risk for viral contamination. Surveillance pilot study.

    Science.gov (United States)

    Cavari, Yuval; Kaplan, Or; Zander, Aviva; Hazan, Guy; Shemer-Avni, Yonat; Borer, Abraham

    2016-01-01

    Mobile phones are commonly used by healthcare workers (HCW) in the working environment, as they allow instant communication and endless resource utilisation. Studies suggest that mobile phones have been implicated as reservoirs of bacterial pathogens, with the potential to cause nosocomial infection. This study aimed to investigate the presence of Respiratory Syncytial Virus, Adenovirus and Influenza Virus on HCWs mobile phones and to identify risk factors implied by HCWs practice of mobile phones in a clinical paediatric environment. Fifty HCWs' mobile phones were swabbed over both sides of the mobile phone, for testing of viral contamination during 8 days in January 2015. During the same period, a questionnaire investigating usage of mobile phones was given to 101 HCWs. Ten per cent of sampled phones were contaminated with viral pathogens tested for. A total of 91% of sampled individuals by questionnaire used their mobile phone within the workplace, where 37% used their phone at least every hour. Eighty-nine (88%) responders were aware that mobile phones could be a source of contamination, yet only 13 (13%) disinfect their cell phone regularly. Mobile phones in clinical practice may be contaminated with viral pathogenic viruses. HCWs use their mobile phone regularly while working and, although the majority are aware of contamination, they do not disinfect their phones.

  19. MANF Promotes Differentiation and Migration of Neural Progenitor Cells with Potential Neural Regenerative Effects in Stroke

    DEFF Research Database (Denmark)

    Tseng, Kuan-Yin; Anttila, Jenni E; Khodosevich, Konstantin

    2018-01-01

    die shortly after injury or are unable to arrive at the infarct boundary. In this study, we demonstrate for the first time that endogenous mesencephalic astrocyte-derived neurotrophic factor (MANF) protects NSCs against oxygen-glucose-deprivation-induced injury and has a crucial role in regulating NPC...... migration. In NSC cultures, MANF protein administration did not affect growth of cells but triggered neuronal and glial differentiation, followed by activation of STAT3. In SVZ explants, MANF overexpression facilitated cell migration and activated the STAT3 and ERK1/2 pathway. Using a rat model of cortical...... stroke, intracerebroventricular injections of MANF did not affect cell proliferation in the SVZ, but promoted migration of doublecortin (DCX)+ cells toward the corpus callosum and infarct boundary on day 14 post-stroke. Long-term infusion of MANF into the peri-infarct zone increased the recruitment...

  20. Potential of Trichoderma spp. strains for the bioremediation of soils contaminated with petroleum

    Directory of Open Access Journals (Sweden)

    Marcia Pesántez

    2016-10-01

    Full Text Available Fungi species can degrade xenobiotic compounds contaminating the soil, including hydrocarbons. The objective of this work was to determine the potential of three strains of Trichoderma, isolated from soil contaminated with petroleum, for bioremediation. Trichoderma harzianum CCECH-Te1, Trichoderma viride CCECH-Te2 and Trichoderma psedokoningii CCECH-Te3 were included in one assay with each independent strain. The inoculum was adjusted to a concentration of 1x1010 conidia ml-1 which was applied to soil contaminated by an oil spill. After 96 days of inoculation, soil samples were taken at 10 and 15 cm depth. The content of total hydrocarbons, polycyclic aromatic hydrocarbons and heavy metals such as cadmium, nickel and lead were determined. With the data, it was calculated the percentage of removal of the analyzed compounds by each strain. At 10 cm and 15 cm depth, it was observed the removal of the compounds in percentages that reached between 47 and 69.1% in the hydrocarbons and up to 53.72% in the heavy metals. It which denoted the potential of the three strains for bioremediation in contaminated soils.   Keywords: heavy metals, polycyclic aromatic hydrocarbons, xenobiotic compounds

  1. Potential for saturated ground-water system contamination at the Lawrence Livermore National Laboratory

    International Nuclear Information System (INIS)

    Stone, R.; Ruggieri, M.R.; Rogers, L.L.; Emerson, D.O.; Buddemeier, R.W.

    1982-01-01

    A program of hydrogeologic investigation has been carried out to determine the likelihood of contaminant movement to the saturated zone from near the ground surface at Lawrence Livermore National Laboratory (LLNL). A companion survey of potential contaminant sources was also conducted at the LLNL. Water samples from selected LLNL wells were analyzed to test the water quality in the uppermost part of the saturated zone, which is from 14 to 48 m (45 to 158 ft) beneath the surface. Only nitrate and tritium were found in concentrations above natural background. In one well, the nitrate was slightly more concentrated than the drinking water limit. The nitrate source has not been found. The tritium in all ground-water samples from wells was found far less concentrated than the drinking water limit. The extent of infiltration of surface water was traced with environmental tritium. The thickness and stratigraphy of the unsaturated zone beneath the LLNL, and nearby area, was determined with specially constructed wells and boreholes. Well hydrograph analysis indicated where infiltration of surface water reached the saturated ground-water system. The investigation indicates that water infiltrating from the surface, through alluvial deposits, reaches the saturated zone along the course of Arroyo Seco, Arroyo Las Positas, and from the depression near the center of the site where seasonal water accumulates. Several potential contaminant sources were identified, and it is likely that contaminants could move from near the ground surface to the saturated zone beneath LLNL. Additional ground-water sampling and analysis will be performed and ongoing investigations will provide estimates of the speed with which potential contaminants can flow laterally in the saturated zone beneath LLNL. 34 references, 61 figures, 16 tables

  2. Final Report: Caustic Waste-Soil Weathering Reactions and Their Impacts on Trace Contaminant Migration and Sequestration

    International Nuclear Information System (INIS)

    O'Day, Peggy A.; Chorover, J.; Mueller, K.T.; Serne, R.J.

    2006-01-01

    The principal goal of this project was to assess the molecular nature and stability of radionuclide (137-Cs, 90-Sr, and 129-I) immobilization during weathering reactions in bulk Hanford sediments and their high surface area clay mineral constituents. We focused on the unique aqueous geochemical conditions that are representative of waste-impacted locations in the Hanford site vadose zone: high ionic strength, high pH and high Al concentrations. The specific objectives of the work were to (i) measure the coupling of clay mineral weathering and contaminant uptake kinetics of Cs+, Sr2+ and I-; (ii) determine the molecular structure of contaminant binding sites and their change with weathering time during and after exposure to synthetic tank waste leachate (STWL); (iii) establish the stability of neoformed weathering products and their sequestered contaminants upon exposure of the solids to more ''natural'' soil solutions (i.e., after removal of the caustic waste source); and (iv) integrate macroscopic, microscopic and spectroscopic data to distinguish labile from non-labile contaminant binding environments, including their dependence on system composition and weathering time. During this funding period, we completed a large set of bench-scale collaborative experiments and product characterization aimed at elucidating the coupling between mineral transformation reactions and contaminant sequestration/stabilization. Our experiments included three representative Hanford sediments: course and fine sediments collected from the Hanford Formation and Ringold Silt, in addition to investigations with specimen clay minerals illite, vermiculite, smectite and kaolinite. These experiments combined macroscopic measurements of element release, contaminant uptake and subsequent neoformed mineral dissolution behavior, with detailed studies of solid phase products using SEM and TEM microscopy, NMR, XAS and FTIR spectroscopy. Our studies have shown direct coupling between mineral

  3. Batch Kd measurements of nuclides to estimate migration potential at the proposed Waste Isolation Pilot Plant in New Mexico

    International Nuclear Information System (INIS)

    Serne, R.J.; Rai, D.; Mason, M.J.; Molecke, M.A.

    1977-01-01

    Laboratory measurements to determine the sorption distribution coefficients, Kd, of radionuclides present in, and potentially leached from, radioactive wastes, in contact with representative geologic media, have been conducted. The nuclides studied include Cs, Sr, Tc, Ru, Sb, Ce, Eu, Pu, Np, Cm, Am, U, and Pa. The crushed rock materials used were from the vicinity of the Waste Isolation Pilot Plant, a project to isolate radioactive wastes in a bedded salt facility, near Carlsbad, New Mexico. Solutions used consist of salt brine and groundwater, specific to the WIPP site, plus distilled water, for laboratory intercomparisons. The batch Kd data reported, plus data from sorption and migration measurements being conducted or planned elsewhere, will be used to evaluate the potential for radionuclide migration from the bedded salt WIPP facility. The data can be used for transport modeling and for safety assessment determinations

  4. Development of methods and criteria for a standardized evaluation of contaminated sites and abandoned waste disposal sites particularly concerning their ground water contamination potential. Pt. 1. Final Report

    International Nuclear Information System (INIS)

    Kerndorff, H.; Schleyer, R.; Arneth, J.D.; Struppe, T.; Milde, G.

    1994-01-01

    Contaminated sites should be evaluated to such an extend, that nearly all risks for man and environment can be safely estimated. An assessment for such sites is presented which combines a substance-specific and a site-specific evaluation. It is a standardized path-specific concept in which - as an example - the contamination path ''waste - groundwater - drinking-water'' is investigated and evaluated in detail. Path-specific main contaminants are established on a statistic basis and ranked according to normalized evaluation numbers of 1-100. Their toxicity potential is calculated for which a particular and standardized method was developed. Main contaminants having a high toxicity potential are called priority contaminants. For the most important exposure/usage on this contamination path, the drinking-water catchment, hygienic and toxicologic based standards are presented. Together with site-specific conditions and the also path-specific and normalized transfer/persistency potential of the priority contaminants it is possible to come to a site- and usage/exposure-specific evaluation of individual sites. (orig.) [de

  5. Behavior and potential threats to survival of migrating lamprey ammocoetes and macrophthalmia

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Mary L.; Jackson, Aaron D.; Lucas, Martyn C.; Mueller, Robert P.

    2015-03-01

    Upon metamorphosis, anadromous juvenile lamprey (macrophthalmia) exhibit distinct migration behaviors that take them from larval rearing habitats in streams to the open ocean. While poorly studied, lamprey larvae (ammocoetes) also engage in downstream movement to some degree. Like migrating salmon smolts, lamprey macrophthalmia undergo behavioral changes associated with a highly synchronized metamorphosis. Unlike salmon smolts, the timing of juvenile migration in lamprey is protracted and poorly documented. Lamprey macrophthalmia and ammocoetes are not strong swimmers, attaining maximum individual speeds of less than 1 m s-1, and sustained speeds of less than 0.5 m s-1. They are chiefly nocturnal and distribute throughout the water column, but appear to concentrate near the bottom in the thalweg of deep rivers. At dams and irrigation diversions, macrophthalmia can become impinged on screens or entrained in irrigation canals, suffer increased predation, and experience physical injury that may result in direct or delayed mortality. The very structures designed to protect migrating juvenile salmonids can be harmful to juvenile lamprey. Yet at turbine intakes and spillways, lampreys, which have no swim bladder, can withstand changes in pressure and shear stress large enough to injure or kill most teleosts. Lamprey populations are in decline in many parts of the world, with some species designated as species of concern for conservation that merit legally mandated protections. Hence, provisions for safe passage of juvenile lamprey are being considered at dams and water diversions in North America and Europe.

  6. Macrophage migration inhibitory factor as a potential prognostic factor in gastric cancer

    Science.gov (United States)

    He, Long-Jun; Xie, Dan; Hu, Pin-Jin; Liao, Yi-Ji; Deng, Hai-Xia; Kung, Hsiang-Fu; Zhu, Sen-Lin

    2015-01-01

    AIM: To investigate macrophage migration inhibitory factor (MIF) expression and its clinical relevance in gastric cancer, and effects of MIF knockdown on proliferation of gastric cancer cells. METHODS: Tissue microarray containing 117 samples of gastric cancer and adjacent non-cancer normal tissues was studied for MIF expression by immunohistochemistry (IHC) semiquantitatively, and the association of MIF expression with clinical parameters was analyzed. MIF expression in gastric cancer cell lines was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Two pairs of siRNA targeting the MIF gene (MIF si-1 and MIF si-2) and one pair of scrambled siRNA as a negative control (NC) were designed and chemically synthesized. All siRNAs were transiently transfected in AGS cells with OligofectamineTM to knock down the MIF expression, with the NC group and mock group (OligofectamineTM alone) as controls. At 24, 48, and 72 h after transfection, MIF mRNA was analyzed by RT-PCR, and MIF and proliferating cell nuclear antigen (PCNA) proteins were detected by Western blot. The proliferative rate of AGS cells was assessed by methylthiazolyl tetrazolium (MTT) assay and colony forming assay. RESULTS: The tissue microarray was informative for IHC staining, in which the MIF expression in gastric cancer tissues was higher than that in adjacent non-cancer normal tissues (P < 0.001), and high level of MIF was related to poor tumor differentiation, advanced T stage, advanced tumor stage, lymph node metastasis, and poor patient survival (P < 0.05 for all). After siRNA transfection, MIF mRNA was measured by real-time PCR, and MIF protein and PCNA were assessed by Western blot analysis. We found that compared to the NC group and mock group, MIF expression was knocked down successfully in gastric cancer cells, and PCNA expression was downregulated with MIF knockdown as well. The cell counts and the doubling times were assayed by MTT 4 d after transfection, and

  7. Butyltin contamination in Northern Chilean coast: Is there a potential risk for consumers?

    Science.gov (United States)

    Mattos, Yasna; Stotz, Wolfgang B; Romero, María Soledad; Bravo, Manuel; Fillmann, Gilberto; Castro, Ítalo B

    2017-10-01

    Imposex is the superimposition of non-functional male sex organs in gastropod females. This syndrome is a hormonal imbalance induced by tributyltin (TBT) which have been used in antifouling paints formulation. The present study aimed to perform an integrated environmental assessment of imposex and butyltin (BT) contamination using surface sediments and tissues of Thaisella chocolata (an edible gastropod) from northern Chile. The results showed imposex incidence in 11 out of 12 sites. In the most contaminated sites, which are areas under the influence of maritime activities, and also used for fishing and aquaculture, RPLI were over 60 and VDSI over 4 (high incidence of sterile females). Exceptionally high contamination levels and evidences of fresh inputs of tributyltin (TBT) were detected along the studied area. TBT levels above 300 and 90ngSng -1 , respectively, were recorded in sediments and edible gastropod tissues of 6 sites. Thus, a daily ingestion of 90 to 173g of T. chocolata foot (4 to 8 organisms) from the most contaminated sites will certainly lead to the consumption of BT exceeding the tolerable daily intake recommended by European Food Safety Authority. It is reasonable to consider that human risk is even higher if daily consumption of additional seafood is considered. Moreover, some contaminated sites were located within the marine reserve "Isla Grande Atacama", indicating that even marine protected areas are under the influence of TBT contamination. These findings suggest that current levels of TBT in the studied area are sufficient to induce harmful effects on the environment and constitutes a potential threat to seafood consumers. Thus, national regulatory actions toward environmental protection and food safety of local populations are still mandatory, even after 8years of the TBT global ban by IMO. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Phytoextraction potential of sunflower and white mustard plants in zinc-contaminated soil

    Directory of Open Access Journals (Sweden)

    Marta Zalewska

    2014-12-01

    Full Text Available Phytoextraction relies on plants with a high capacity to absorb heavy metals and remove them from the soil. The objective of this study was to analyze the potential of sunflower (Helianthus annuus L. and white mustard (Sinapis alba L. for phytoextraction of Zn-contaminated soil. Research was based on a strict pot experiment conducted in a greenhouse. Seven treatments were established with increasing Zn concentrations: 0, 25, 50, 100, 200, 400, and 600 mg Zn kg-1 air-dry soil. The first tested plant was fodder sunflower. In the following year, white mustard was sown in the same pots. Plants were harvested at the end of the flowering stage. The toxic effect of Zn on sunflower yields occurred at the contamination level of 200 mg Zn kg-1 soil. In the second year of the experiment, a significant decrease in mustard biomass took place in response to 400 mg Zn kg-1 soil. The contamination level of 600 mg Zn kg-1 soil resulted in complete plant death. Plant growth was not inhibited even at high tissue Zn concentrations of 515 mg Zn kg-1 sunflower DM and 422 mg Zn kg-1 mustard DM. The 2-yr cropping system did not contribute to a significant decrease in soil Zn content. Despite high concentrations of Zn in sunflower and mustard plants, total Zn uptake accounted for only 1% to 8% of the Zn rate introduced into the soil. However, in the long run, the growing of crops could reduce Zn contamination levels in the soil. The relatively high tolerance of sunflower and white mustard for Zn contamination and rapid growth of these species are possible alternatives for phytoextraction and phytostabilization of Zn-contaminated soil.

  9. Petroleum Hydrocarbons Contamination Profile of Ochani Stream in ...

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: Petroleum hydrocarbon contamination profile, heavy metals and .... potential conduits for oil and water migrating from the ... by Gas Chromatography: Soil / sediment / sludge ..... fractions contained in the dump pits) which have.

  10. Rapid Analysis of Eukaryotic Bioluminescence to Assess Potential Groundwater Contamination Events

    Directory of Open Access Journals (Sweden)

    Zacariah L. Hildenbrand

    2015-01-01

    Full Text Available Here we present data using a bioluminescent dinoflagellate, Pyrocystis lunula, in a toxicological bioassay to rapidly assess potential instances of groundwater contamination associated with natural gas extraction. P. lunula bioluminescence can be quantified using spectrophotometry as a measurement of organismal viability, with normal bioluminescent output declining with increasing concentration(s of aqueous toxicants. Glutaraldehyde and hydrochloric acid (HCl, components used in hydraulic fracturing and shale acidization, triggered significant toxicological responses in as little as 4 h. Conversely, P. lunula was not affected by the presence of arsenic, selenium, barium, and strontium, naturally occurring heavy metal ions potentially associated with unconventional drilling activities. If exogenous compounds, such as glutaraldehyde and HCl, are thought to have been introduced into groundwater, quantification of P. lunula bioluminescence after exposure to water samples can serve as a cost-effective detection and risk assessment tool to rapidly assess the impact of putative contamination events attributed to unconventional drilling activity.

  11. Biofuel and other biomass based products from contaminated sites - Potentials and barriers from Swedish perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Andersson-Skoeld, Yvonne; Enell, Anja; Rihm, Thomas; Haglund, Kristina; Wik, Ola [Swedish Geotechnical Institute, Linkoeping (Sweden); Blom, Sonja; Angelbratt, Alexandra [FB Engineering AB, Goeteborg (Sweden); Bardos, Paul [r3 Environmental Technology Ltd, Reading (United Kingdom); Track, Thomas [DECHEMA e. V., Frankfurt am Main (Germany); Keuning, Sytze [Bioclear b.v., Groningen (Netherlands)

    2009-07-01

    In this report, results are presented based on interviews and literature surveys on the triggers and stoppers for non food crop on contaminated land in Sweden. The report also includes a first estimate of potential marginal land for biofuel production in Sweden. The report is a first step to explore the feasibility of a range of possible approaches to combine risk based land management (RBLM) with non-food crop land-uses and organic matter re-use as appropriate in a Swedish context. The focus of the report is on the treatment of contaminated land by phyto-remediation and on biofuel cultivation. In Sweden, like all other countries in Europe, areas of land have been degraded by past use. Such previously developed land includes areas affected by mining, fallout from industrial processes such as smelting, areas elevated with contaminated dredged sediments, former landfill sites and many other areas where the decline of industrial activity has left a legacy of degraded land and communities. The extent of contamination may not be sufficient to trigger remediation under current regulatory conditions, and there may be little economic incentive to regenerate the affected areas. An ideal solution would be a land management approach that is able to pay for itself. Biomass from coppice or other plantations has long been seen as a possible means of achieving this goal. Phyto remediation offers a low cost method for remediation of areas that are not candidates for conventional regeneration. The optimal conditions for phyto remediation are large land areas of low or mediate contamination. Phyto remediation is also suitable to prevent spreading of contaminants, for example in green areas such as in cities, as waste water buffer and small size remediation areas with diffuse spreading. Phyto remediation implies that plants, fungi or algae are used to remediate, control or increase the natural attenuation of contaminants. Depending on the contaminating species and the site conditions

  12. Biofuel and other biomass based products from contaminated sites - Potentials and barriers from Swedish perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Andersson-Skoeld, Yvonne; Enell, Anja; Rihm, Thomas; Haglund, Kristina; Wik, Ola (Swedish Geotechnical Institute, Linkoeping (Sweden)); Blom, Sonja; Angelbratt, Alexandra (FB Engineering AB, Goeteborg (Sweden)); Bardos, Paul (r3 Environmental Technology Ltd, Reading (United Kingdom)); Track, Thomas (DECHEMA e. V., Frankfurt am Main (Germany)); Keuning, Sytze (Bioclear b.v., Groningen (Netherlands))

    2009-07-01

    In this report, results are presented based on interviews and literature surveys on the triggers and stoppers for non food crop on contaminated land in Sweden. The report also includes a first estimate of potential marginal land for biofuel production in Sweden. The report is a first step to explore the feasibility of a range of possible approaches to combine risk based land management (RBLM) with non-food crop land-uses and organic matter re-use as appropriate in a Swedish context. The focus of the report is on the treatment of contaminated land by phyto-remediation and on biofuel cultivation. In Sweden, like all other countries in Europe, areas of land have been degraded by past use. Such previously developed land includes areas affected by mining, fallout from industrial processes such as smelting, areas elevated with contaminated dredged sediments, former landfill sites and many other areas where the decline of industrial activity has left a legacy of degraded land and communities. The extent of contamination may not be sufficient to trigger remediation under current regulatory conditions, and there may be little economic incentive to regenerate the affected areas. An ideal solution would be a land management approach that is able to pay for itself. Biomass from coppice or other plantations has long been seen as a possible means of achieving this goal. Phyto remediation offers a low cost method for remediation of areas that are not candidates for conventional regeneration. The optimal conditions for phyto remediation are large land areas of low or mediate contamination. Phyto remediation is also suitable to prevent spreading of contaminants, for example in green areas such as in cities, as waste water buffer and small size remediation areas with diffuse spreading. Phyto remediation implies that plants, fungi or algae are used to remediate, control or increase the natural attenuation of contaminants. Depending on the contaminating species and the site conditions

  13. Potential economic losses to the US corn industry from aflatoxin contamination.

    Science.gov (United States)

    Mitchell, Nicole J; Bowers, Erin; Hurburgh, Charles; Wu, Felicia

    2016-01-01

    Mycotoxins, toxins produced by fungi that colonise food crops, can pose a heavy economic burden to the US corn industry. In terms of economic burden, aflatoxins are the most problematic mycotoxins in US agriculture. Estimates of their market impacts are important in determining the benefits of implementing mitigation strategies within the US corn industry, and the value of strategies to mitigate mycotoxin problems. Additionally, climate change may cause increases in aflatoxin contamination in corn, greatly affecting the economy of the US Midwest and all sectors in the United States and worldwide that rely upon its corn production. We propose two separate models for estimating the potential market loss to the corn industry from aflatoxin contamination, in the case of potential near-future climate scenarios (based on aflatoxin levels in Midwest corn in warm summers in the last decade). One model uses the probability of acceptance based on operating characteristic (OC) curves for aflatoxin sampling and testing, while the other employs partial equilibrium economic analysis, assuming no Type 1 or Type 2 errors, to estimate losses due to proportions of lots above the US Food and Drug Administration (USFDA) aflatoxin action levels. We estimate that aflatoxin contamination could cause losses to the corn industry ranging from US$52.1 million to US$1.68 billion annually in the United States, if climate change causes more regular aflatoxin contamination in the Corn Belt as was experienced in years such as 2012. The wide range represents the natural variability in aflatoxin contamination from year to year in US corn, with higher losses representative of warmer years.

  14. Aerobic biodegradation potential of subsurface microorganisms from a jet fuel-contaminated aquifer

    International Nuclear Information System (INIS)

    Aelion, C.M.; Bradley, P.M.

    1991-01-01

    Current efforts to remediate subsurface contamination have spurred research in the application of in situ bioremediation. In 1975, a leak of 83,000 gallons (314,189 liters) of jet fuel (JP-4) contaminated a shallow water-table aquifer near North Charleston, S.C. Laboratory experiments were conducted with contaminated sediments to assess the aerobic biodegradation potential of the in situ microbial community. Sediments were incubated with 14 C-labeled organic compounds, and the evolution of 14 CO 2 was measured over time. Gas chromatographic analyses were used to monitor CO 2 production and O 2 consumption under aerobic conditions. Results indicated that the microbes from contaminated sediments remained active despite the potentially toxic effects of JP-4. 14 CO 2 was measured from [ 14 C]glucose respiration in unamended and nitrate-amended samples after 1 day of incubation. Total [ 14 C]glucose metabolism was greater in 1 mM nitrate-amended than in unamended samples because of increased cellular incorporation of 14 C label. [ 14 C]benzene and [ 14 C]toluene were not significantly respired after 3 months of incubation. With the addition of 1 mM NO 3 , CO 2 production measured by gas chromatographic analysis increased linearly during 2 months of incubation at a rte of 0.099 μmol g -1 (dry weight) day -1 while oxygen concentration decreased at a rate of 0.124 μmol g -1 (dry weight) day -1 . With no added nitrate, CO 2 production was not different from that in metabolically inhibited control vials. The results suggest that the in situ microbial community is active despite the JP-4 jet fuel contamination and that biodegradation may be compound specific. Also, the community is strongly nitrogen limited, and nitrogen additions may be required to significantly enhance hydrocarbon biodegradation

  15. Potential economic losses to the USA corn industry from aflatoxin contamination

    Science.gov (United States)

    Mitchell, N.J.; Bowers, E.; Hurburgh, C.; Wu, F.

    2016-01-01

    Mycotoxins, toxins produced by fungi that colonize food crops, can pose a heavy economic burden to the United States corn industry. In terms of economic burden, aflatoxins are the most problematic mycotoxins in US agriculture. Estimates of their market impacts are important in determining the benefits of implementing mitigation strategies within the US corn industry, and the value of strategies to mitigate mycotoxin problems. Additionally, climate change may cause increases in aflatoxin contamination in corn, greatly affecting the economy of the US Midwest and all sectors in the US and worldwide that rely upon its corn production. We propose two separate models for estimating the potential market loss to the corn industry from aflatoxin contamination, in the case of potential near-future climate scenarios (based on aflatoxin levels in Midwest corn in warm summers in the last decade). One model uses probability of acceptance based on operating characteristic (OC) curves for aflatoxin sampling and testing, while the other employs partial equilibrium economic analysis, assuming no Type 1 or Type 2 errors, to estimate losses due to proportions of lots above the US Food and Drug Administration (FDA) aflatoxin action levels. We estimate that aflatoxin contamination could cause losses to the corn industry ranging from $52.1 million to $1.68 billion annually in the United States, if climate change causes more regular aflatoxin contamination in the Corn Belt as was experienced in years such as 2012. The wide range represents the natural variability in aflatoxin contamination from year to year in US corn, with higher losses representative of warmer years. PMID:26807606

  16. Immunostimulatory Potential of β-Lactoglobulin Preparations: Effects Caused by Endotoxin Contamination

    DEFF Research Database (Denmark)

    Pedersen, Susanne Brix; Bovetto, L.; Fritsche, R.

    2003-01-01

    Background: The immunomodulating potential residing in cow's milk proteins is currently receiving increasing attention because of growing interest in functional foods and the complex problem of cow's milk allergy. One of the major cow's milk allergens, whey protein beta-lactoglobulin, has...... the immunomodulatory activity. Eventually, the immunostimulatory effect was found to be caused by endotoxin contamination.Conclusion: These results identify endotoxin as the main immunostimulatory component present in some commercial beta-lactoglobulin preparations. Moreover, the present study makes it evident...

  17. Hyperspectral fluorescence imaging of animal feces and soil: potential use of fluorescence imaging for assessment of soil fecal contamination and compost maturity

    Science.gov (United States)

    Contamination by pathogenic microorganisms can lead to serious illnesses, particularly if thermal mishandling of contaminated agricultural produce occurs and promotes the incubation of potential pathogens. Pathogenic microbial contamination of agricultural products can occur through a variety of pat...

  18. Hydrology of the solid waste burial ground, as related to the potential migration of radionuclides, Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Barraclough, J.T.; Robertson, J.B.; Janzer, V.J.; Saindon, L.G.

    1976-08-01

    This report describes a study conducted by the U. S. Geological Survey with the following objectives: to evaluate the hydrologic, radiologic and geochemical variables that control the potential for subsurface migration of waste radionuclides from the burial trenches to the Snake River Plain aquifer; to determine the extent of radionuclide migration, if any; and, to construct monitoring wells into the aquifer. Statistically significant trace amounts of radioactivity were found in about one-half of the 44 sedimentary samples from the six holes core drilled inside the burial ground and from all water samples from one hole tapping a perched water table. These very low levels of radioactivity are detectable only with the most sensitive of analytical equipment and techniques. The levels of radioactivity detected were, in most cases, less than the amounts found in surface soils in this region resulting from world-wide fallout. This radioactivity found in the cores could have been introduced naturally by migration by infiltrating water which had made contact with buried waste or could have been introduced artificially during drilling and sampling. The available data from the four peripheral monitoring wells do not indicate that radionuclide constituents from the burial ground have migrated into the underlying Snake River Plain aquifer. The low concentrations of radionuclides detected in samples taken from the sedimentary layers are not expected to migrate to the Snake River Plain aquifer. Water samples from the peripheral wells and one core hole inside the burial ground will continue to be collected and analyzed for radioactivity semi-annually

  19. 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.

  20. Phytoremediation potential of willow tress for aquifers contaminated with ethanol-blended gasoline

    Energy Technology Data Exchange (ETDEWEB)

    Corseuil, H.X. [Universidade Federal de Santa Catarina, Florianopolis (Brazil). Departamento de Engenharia Sanitaria e Ambiental; Moreno, F.N. [Universidade do Sul de Santa Catarina, Palhoca (Brazil). Centro de Ciencias Agrarias e das Engenharias

    2001-07-01

    Ethanol-blended gasoline has been used in Brazil for 20 years and, probably, is going to be more widely used in North America due to the MtBE environmental effects on groundwater. The potential impacts caused by the presence of ethanol in UST spills are related to the co-solvency effect and the preferential degradation of ethanol over the BTEX compounds. These interactions may increase the length of dissolved hydrocarbon plumes and the costs associated with site remediation. This study investigates the advantages of phytoremediation to overcome the problems associated with the presence of ethanol in groundwater contaminated with gasoline-ethanol mixtures. Experiments were performed under lab conditions with cuttings of Willow tree (Salix babylonica) cultivated hydroponically. Results showed that the cuttings were able to reduce ethanol and benzene concentrations by more than 99% in less than a week. The uptake of both contaminants was confirmed by blank controls and was significantly related to cuttings transpiration capacity. Sorption onto roots biomass also markedly affected the behavior of contaminants in solution. Experiments to evaluate plants' toxicity to ethanol indicated that plants were only affected when aqueous ethanol concentration reached 2000mgl{sup -1}. Results suggest that phytoremediation can be a good complement to intrinsic remediation in shallow aquifer sites contaminated with ethanol-blended gasoline spills. (Author)

  1. Pollution potential of oil-contaminated soil on groundwater resources in Kuwait

    International Nuclear Information System (INIS)

    Literathy, P.; Quinn, M.; Al-Rashed, M.

    2003-01-01

    The only natural freshwater resource of Kuwait occurs as lenses floating on the saline groundwater in the northern part of the country, near to the oil fields. Rainwater is the only means of recharge of this limited groundwater resource. This groundwater is used as bottled drinking water and the fresh groundwater aquifer is considered as a strategic drinking water reserve for Kuwait. As a result of the 1991 Gulf War, the upper soil layer has been widely contaminated with crude oil and crude oil combustion products, which are potential pollutants likely affecting the groundwater resources. Significant efforts have been made to assess this pollution. These included: (a) a soil survey for assessing the soil contamination, and (b) leaching experiments to characterise the mobilization of the soil-associated pollutants. Fluorescence measurement techniques were used during field surveys as well as for laboratory testing. In addition, determination of the total extractable matter (TEM), total petroleum hydrocarbons (TPH), and GC/MS measurement of polyaromatic hydrocarbons (PAHs) were performed for the assessments. The laser induced fluorescence (LIF) measurement, having good correlation with the other laboratory measurements, was proved to provide necessary information for the assessment of the oil-contamination level in the desert soil. The subsequent leaching test with water demonstrated the mobilization of the fluorescing compounds (e.g. PAHs), and the alteration in the leaching characteristics of the contamination during the long term environmental weathering of the oil. (author)

  2. Potential for effects of land contamination on human health. 2. The case of waste disposal sites.

    Science.gov (United States)

    Kah, Melanie; Levy, Len; Brown, Colin

    2012-01-01

    This review of the epidemiological literature shows that evidence for negative impacts of land contaminated by waste disposal on human health is limited. However, the potential for health impacts cannot be dismissed. The link between residence close to hazardous waste disposal sites and heightened levels of stress and anxiety is relatively well established. However, studies on self-reported outcomes generally suffer from interpretational problems, as subjective symptoms may be due to increased perception and recall. Several recent multiple-site studies support a plausible linkage between residence near waste disposal sites and reproductive effects (including congenital anomalies and low birth weight). There is some conflict in the literature investigating links between land contamination and cancers; the evidence for and against a link is equally balanced and is insufficient to make causal inferences. These are difficult to establish because of lack of data on individual exposures, and other socioeconomic and lifestyle factors that may confound a relationship with area of residence. There is no consistently occurring risk for any specific tumor across multiple studies on sites expected to contain similar contaminants. Further insights on health effects of land contamination are likely to be gained from studies that consider exposure pathways and biomarkers of exposure and effect, similar to those deployed with some success in investigating impacts of cadmium on human health.

  3. The potential role of diffusion-induced grain-boundary migration in extended life prediction

    International Nuclear Information System (INIS)

    Handwerker, C.A.; Blendell, J.E.; Interrante, C.G.; Ahn, T.M.

    1993-01-01

    The selection of materials that are suitable for various high-level waste-packaging designs must reflect the need to meet requirements for long-term performance in repository environments that change with time. With this in mind, we examine how grain boundaries in materials are induced to migrate as a result of solute diffusion even at low temperatures, how the composition of the matrix material is changed significantly by this diffusion-induced grain boundary migration (DIGM), and how the changing microstructures and compositions during DIGM lead to major changes in materials performance, such as corrosion or embrittlement. Methods are discussed for prediction of the long-term behavior of materials affected by DIGM

  4. Brazilian Red Propolis Induces Apoptosis-Like Cell Death and Decreases Migration Potential in Bladder Cancer Cells

    Directory of Open Access Journals (Sweden)

    Karine Rech Begnini

    2014-01-01

    Full Text Available Natural products continue to be an invaluable resource of anticancer drug discovery in recent years. Propolis is known for its biological activities such as antimicrobial and antitumor effects. This study assessed the effects of Brazilian red propolis (BRP on apoptosis and migration potential in human bladder cancer cells. The effect of BRP ethanolic extract (25, 50, and 100 μg/mL on 5637 cells was determined by MTT, LIVE/DEAD, and migration (scratch assay assays. Apoptosis induction was investigated through flow cytometry and gene expression profile was investigated by qRT-PCR. Results showed cytotoxicity on MTT and LIVE/DEAD assays, with IC50 values of 95 μg/mL in 24 h of treatment. Cellular migration of 5637 cells was significantly inhibited through lower doses of BRP ethanolic extract (25 and 50 μg/mL. Flow cytometry analyses showed that BRP induced cytotoxicity through apoptosis-like mechanisms in 5637 cells and qRT-PCR revealed increased levels of Bax/Bcl-2 ratio, p53, AIF, and antioxidant enzymes genes. Data suggest that BRP may be a potential source of drugs to bladder cancer treatment.

  5. Brazilian red propolis induces apoptosis-like cell death and decreases migration potential in bladder cancer cells.

    Science.gov (United States)

    Begnini, Karine Rech; Moura de Leon, Priscila Marques; Thurow, Helena; Schultze, Eduarda; Campos, Vinicius Farias; Martins Rodrigues, Fernanda; Borsuk, Sibele; Dellagostin, Odir Antônio; Savegnago, Lucielli; Roesch-Ely, Mariana; Moura, Sidnei; Padilha, Francine F; Collares, Tiago; Pêgas Henriques, João Antonio; Seixas, Fabiana Kömmling

    2014-01-01

    Natural products continue to be an invaluable resource of anticancer drug discovery in recent years. Propolis is known for its biological activities such as antimicrobial and antitumor effects. This study assessed the effects of Brazilian red propolis (BRP) on apoptosis and migration potential in human bladder cancer cells. The effect of BRP ethanolic extract (25, 50, and 100 μg/mL) on 5637 cells was determined by MTT, LIVE/DEAD, and migration (scratch assay) assays. Apoptosis induction was investigated through flow cytometry and gene expression profile was investigated by qRT-PCR. Results showed cytotoxicity on MTT and LIVE/DEAD assays, with IC50 values of 95 μg/mL in 24 h of treatment. Cellular migration of 5637 cells was significantly inhibited through lower doses of BRP ethanolic extract (25 and 50 μg/mL). Flow cytometry analyses showed that BRP induced cytotoxicity through apoptosis-like mechanisms in 5637 cells and qRT-PCR revealed increased levels of Bax/Bcl-2 ratio, p53, AIF, and antioxidant enzymes genes. Data suggest that BRP may be a potential source of drugs to bladder cancer treatment.

  6. Inflammation and cancer: macrophage migration inhibitory factor (MIF)--the potential missing link.

    LENUS (Irish Health Repository)

    Conroy, H

    2010-11-01

    Macrophage migration inhibitory factor (MIF) was the original cytokine, described almost 50 years ago and has since been revealed to be an important player in pro-inflammatory diseases. Recent work using MIF mouse models has revealed new roles for MIF. In this review, we present an increasing body of evidence implicating the key pro-inflammatory cytokine MIF in specific biological activities related directly to cancer growth or contributing towards a microenvironment favouring cancer progression.

  7. Direct and indirect effects of a potential aquatic contaminant on grazer-algae interactions.

    Science.gov (United States)

    Evans-White, Michelle A; Lamberti, Gary A

    2009-02-01

    Contaminants have direct, harmful effects across multiple ecological scales, including the individual, the community, and the ecosystem levels. Less, however, is known about how indirect effects of contaminants on consumer physiology or behavior might alter community interactions or ecosystem processes. We examined whether a potential aquatic contaminant, an ionic liquid, can indirectly alter benthic algal biomass and primary production through direct effects on herbivorous snails. Ionic liquids are nonvolatile organic salts being considered as an environmentally friendly potential replacement for volatile organic compounds in industry. In two greenhouse experiments, we factorially crossed four concentrations of 1-N-butyl-3-methylimidazolium bromide (bmimBr; experiment 1: 0 or 10 mg/L; experiment 2: 0, 1, or 100 mg/L) with the presence or absence of the snail Physa acuta in aquatic mesocosms. Experimental results were weighted by their respective control (no bmimBr or P. acuta) and combined for statistical analysis. When both bmimBr and snails were present, chlorophyll a abundance and algal biovolume were higher than would be expected if both factors acted additively. In addition, snail growth rates, relative to those of controls, declined by 41 to 101% at 10 and 100 mg/L of bmimBr. Taken together, these two results suggest that snails were less efficient grazers in the presence of bmimBr, resulting in release of algae from the grazer control. Snails stimulated periphyton primary production in the absence, but not in the presence, of bmimBr, suggesting that bmimBr also can indirectly alter ecosystem function. These findings suggest that sublethal contaminant levels can negatively impact communities and ecosystem processes via complex interactions, and they provide baseline information regarding the potential effects of an emergent industrial chemical on aquatic systems.

  8. Geochemistry and migration of contaminants at the Weldon Spring chemical plant site, St. Charles County, Missouri, 1989--91

    International Nuclear Information System (INIS)

    Schumacher, J.G.

    1993-01-01

    Investigations were conducted by the US Geological Survey in cooperation with the US Department of Energy at the Weldon Spring chemical plant site to determine the geochemistry of the shallow aquifer and geochemical controls on the migration of uranium and other constituents from the raffinate (waste) pits. Water-quality analyses from monitoring wells at the site and vicinity property indicate that water in the shallow aquifer is a calcium magnesium bicarbonate type that is at equilibrium with respect to calcite and slightly supersaturated with respect to dolomite

  9. The use of a Phosphate-Based Migrating Corrosion Inhibitor to Repair Reinforced Concrete Elements Contaminated by Chlorides

    Science.gov (United States)

    Tittarelli, Francesca; Mobili, Alessandra; Bellezze, Tiziano

    2017-08-01

    The use of sodium monofluorophosphate (MFP) was experimented as migrator inhibiting treatment against corrosion of reinforced concrete elements induced by chlorides. The results show that sodium monofluorophosphate, applied by surface impregnation, is able to slow down reinforcement corrosion only for reinforcing steel bars with concrete cover not thicker than 1 cm. This limitation is most probably due to the difficulty, with the type of application adopted, in making MFP to reach concentrations high enough to inhibit the corrosive process at greater depths from the impregnation surface.

  10. Protozoan predation in soil slurries compromises determination of contaminant mineralization potential

    International Nuclear Information System (INIS)

    Badawi, Nora; Johnsen, Anders R.; Brandt, Kristian K.; Sørensen, Jan; Aamand, Jens

    2012-01-01

    Soil suspensions (slurries) are commonly used to estimate the potential of soil microbial communities to mineralize organic contaminants. The preparation of soil slurries disrupts soil structure, however, potentially affecting both the bacterial populations and their protozoan predators. We studied the importance of this “slurry effect” on mineralization of the herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA, 14 C-labelled), focussing on the effects of protozoan predation. Mineralization of MCPA was studied in “intact” soil and soil slurries differing in soil:water ratio, both in the presence and absence of the protozoan activity inhibitor cycloheximide. Protozoan predation inhibited mineralization in dense slurry of subsoil (soil:water ratio 1:3), but only in the most dilute slurry of topsoil (soil:water ratio 1:100). Our results demonstrate that protozoan predation in soil slurries may compromise quantification of contaminant mineralization potential, especially when the initial density of degrader bacteria is low and their growth is controlled by predation during the incubation period. - Highlights: ► We studied the protozoan impact on MCPA mineralization in soil slurries. ► Cycloheximide was used as protozoan inhibitor. ► Protozoa inhibited MCPA mineralization in dilute topsoil slurry and subsoil slurry. ► Mineralization potentials may be underestimated when using soil slurries. - Protozoan predation may strongly bias the quantification of mineralization potential when performed in soil slurries, especially when the initial density of degrader bacteria is low such as in subsoil or very dilute topsoil slurries.

  11. Potential contaminants in the food chain: identification, prevention and issue management.

    Science.gov (United States)

    Scanlan, Francis P

    2007-01-01

    Contaminants are a vast subject area of food safety and quality. They are generally divided into chemical, microbiological and physical classes and are present in our food chain from raw materials to finished products. They are the subject of international and national legislation that has widened to cover more and more contaminant classes and food categories. In addition, consumers have become increasingly aware of and alarmed by their risks, whether rightly or not. What is the food industry doing to ensure the safety and quality of the products we feed our children? This is a valid question which this article attempts to address from an industrial viewpoint. Chemical food safety is considered a complex field where the risk perception of consumers is often the highest. The effects of chronic or acute exposure to chemical carcinogens may cause disease conditions long after exposure that can be permanently debilitating or even fatal. It is also a moving target, as knowledge about the toxicity and occurrence data of new chemical contaminants continues to be generated. Their identification, prevention and management are challenges to the food industry as a whole. A reminder of the known chemical hazards in the food chain will be presented with an emphasis on the use of early warning to identify potential new contaminants. Early warning is also a means of prevention, anticipating food safety concerns before they become issues to manage. Current best management practices including Hazard Analysis and Critical Control Points relating to the supply chain of baby foods and infant formulae will be developed. Finally, key lessons from a case study on recent contamination issues in baby food products will be presented.

  12. Potential hazards of environmental contaminants to avifauna residing in the Chesapeake Bay estuary

    Science.gov (United States)

    Rattner, Barnett A.; McGowan, Peter C.

    2007-01-01

    A search of the Contaminant Exposure and Effects-Terrestrial Vertebrates (CEE-TV) database revealed that 70% of the 839 Chesapeake Bay records deal with avian species. Studies conducted on waterbirds in the past 15 years indicate that organochlorine contaminants have declined in eggs and tissues, although p,p'-DDE, total polychlorinated biphenyls (PCBs) and coplanar PCB congeners may still exert sublethal and reproductive effects in some locations. There have been numerous reports of avian die-off events related to organophosphorus and carbamate pesticides. More contemporary contaminants (e.g., alkylphenols, ethoxylates, perfluorinated compounds, polybrominated diphenyl ethers) are detectable in bird eggs in the most industrialized portions of the Bay, but interpretation of these data is difficult because adverse effect levels are incompletely known for birds. Two moderaterized oil spills resulted in the death of several hundred birds, and about 500 smaller spill events occur annually in the watershed. With the exception of lead, concentrations of cadmium, mercury, and selenium in eggs and tissues appear to be below toxic thresholds for waterbirds. Fishing tackle and discarded plastics, that can entangle and kill young and adults, are prevalent in nests in some Bay tributaries. It is apparent that exposure and potential effects of several classes of contaminants (e.g., dioxins, dibenzofurans, rodenticides, pharmaceuticals, personal care products, lead shot, and some metals) have not been systematically examined in the past 15 years, highlighting the need for toxicological evaluation of birds found dead, and perhaps an avian ecotoxicological monitoring program. Although oil spills, spent lead shot, some pesticides, and industrial pollutants occasionally harm Chesapeake avifauna, contaminants no longer evoke the population level effects that were observed in Ospreys (Pandion haliaetus) and Bald Eagles (Haliaeetus leucocephalus) through the 1970s.

  13. Soaking grapevine cuttings in water: a potential source of cross contamination by micro-organisms

    Directory of Open Access Journals (Sweden)

    Helen WAITE

    2013-09-01

    Full Text Available Grapevine nurseries soak cuttings in water during propagation to compensate for dehydration and promote root initiation. However, trunk disease pathogens have been isolated from soaking water, indicating cross contamination. Cuttings of Vitis vinifera cv. Sunmuscat and V. berlandieri x V. rupestris rootstock cv. 140 Ruggeri were immersed in sterilized, deionised water for 1, 2, 4, 8 and 16 h. The soaking water was cultured (25°C for 3 days on non-specific and specific media for fungi and bacteria. The base of each cutting was debarked and trimmed and three 3 mm thick, contiguous, transverse slices of wood cultured at 25°C for 3 days. The soaking water for both cultivars became contaminated with microorganisms within the first hour. Numbers of fungi iso-lated from the wood slices soaked for one hour were significantly greater than those from non-soaked cuttings. The number of bacterial colonies growing from the wood slices increased after soaking for 2‒4 h in Sunmuscat. In a second experiment Shiraz cuttings were soaked for 1, 2, 4, 8 and 24 h. The soaking water became contaminated within the first hour but only the bacterial count increased significantly over time. Microorganisms also established on the container surfaces within the first hour although there were no significant increases over 24 h. These results confirm that soaking cuttings is a potential cause of cross contamination and demonstrate contamination of cuttings occurs after relatively short periods of soaking. Avoiding exposing cuttings to water will reduce the transmission of trunk diseases in propagation.

  14. Arsenic contamination and potential health risk implications at an abandoned tungsten mine, southern China

    International Nuclear Information System (INIS)

    Liu Chuanping; Luo Chunling; Gao Yun; Li Fangbai; Lin Lanwen; Wu Changan; Li Xiangdong

    2010-01-01

    In an extensive environmental study, field samples, including soil, water, rice, vegetable, fish, human hair and urine, were collected at an abandoned tungsten mine in Shantou City, southern China. Results showed that arsenic (As) concentration in agricultural soils ranged from 3.5 to 935 mg kg -1 with the mean value of 129 mg kg -1 . In addition, As concentration reached up to 325 μg L -1 in the groundwater, and the maximum As concentration in local food were 1.09, 2.38 and 0.60 mg kg -1 for brown rice, vegetable and fish samples, respectively, suggesting the local water resource and food have been severely contaminated with As. Health impact monitoring data revealed that As concentrations in hair and urine samples were up to 2.92 mg kg -1 and 164 μg L -1 , respectively, indicating a potential health risk among the local residents. Effective measurements should be implemented to protect the local community from the As contamination in the environment. - It is the first report on arsenic contamination and potential health risk implications at abandoned Lianhuashan tungsten mine.

  15. Final work plan : investigation of potential contamination at the former USDA facility in Powhattan, Kansas.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.; Environmental Science Division

    2007-02-02

    This Work Plan outlines the scope of work to be conducted to investigate the subsurface contaminant conditions at the property formerly leased by the Commodity Credit Corporation (CCC) in Powhattan, Kansas (Figure 1.1). Data obtained during this event will be used to (1) evaluate potential contaminant source areas on the property; (2) determine the vertical and horizontal extent of potential contamination; and (3) provide recommendations for future action, with the ultimate goal of assigning this site No Further Action status. The planned investigation includes groundwater monitoring requested by the Kansas Department of Health and Environment (KDHE), in accordance with Section V of the Intergovernmental Agreement between the KDHE and the Farm Service Agency of the U.S. Department of Agriculture (USDA). The work is being performed on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. A nonprofit, multidisciplinary research center operated by the University of Chicago for the U.S. Department of Energy, Argonne provides technical assistance to the CCC/USDA with environmental site characterization and remediation at former CCC/USDA grain storage facilities. Argonne issued a Master Work Plan (Argonne 2002) that has been approved by the KDHE. The Master Work Plan describes the general scope of all investigations at former CCC/USDA facilities in Kansas and provides guidance for these investigations. It should be consulted for the complete details of plans for work associated with the former CCC/USDA facility at Powhattan.

  16. Plants Rather than Mineral Fertilization Shape Microbial Community Structure and Functional Potential in Legacy Contaminated Soil.

    Science.gov (United States)

    Ridl, Jakub; Kolar, Michal; Strejcek, Michal; Strnad, Hynek; Stursa, Petr; Paces, Jan; Macek, Tomas; Uhlik, Ondrej

    2016-01-01

    Plant-microbe interactions are of particular importance in polluted soils. This study sought to determine how selected plants (horseradish, black nightshade and tobacco) and NPK mineral fertilization shape the structure of soil microbial communities in legacy contaminated soil and the resultant impact of treatment on the soil microbial community functional potential. To explore these objectives, we combined shotgun metagenomics and 16S rRNA gene amplicon high throughput sequencing with data analysis approaches developed for RNA-seq. We observed that the presence of any of the selected plants rather than fertilization shaped the microbial community structure, and the microbial populations of the root zone of each plant significantly differed from one another and/or from the bulk soil, whereas the effect of the fertilizer proved to be insignificant. When we compared microbial diversity in root zones versus bulk soil, we observed an increase in the relative abundance of Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria or Bacteroidetes, taxa which are commonly considered copiotrophic. Our results thus align with the theory that fast-growing, copiotrophic, microorganisms which are adapted to ephemeral carbon inputs are enriched in the vegetated soil. Microbial functional potential indicated that some genetic determinants associated with signal transduction mechanisms, defense mechanisms or amino acid transport and metabolism differed significantly among treatments. Genetic determinants of these categories tend to be overrepresented in copiotrophic organisms. The results of our study further elucidate plant-microbe relationships in a contaminated environment with possible implications for the phyto/rhizoremediation of contaminated areas.

  17. Assessing Contamination Potential of Nitrate-N in Groundwater of Lanyang Plain

    Science.gov (United States)

    Liang, Ching-Ping; Tu, Yu-Lin; Lin, Chien-Wen; Jang, Cheng-Shin

    2013-04-01

    Nitrate-N pollution is often relevant to agricultural activities such as the fertilization of crops. Significant increases in the nitrate-N pollution of groundwater are found in natural recharging zones of Taiwan. The increasing nitrate-N contamination seriously threatens public drinking water supply and human health. Constructing a correct map of aquifer contamination potential is an effective and feasible way to protect groundwater for quality assessment and management. Therefore, in this study, we use DRASTIC model with the help of geographic information system (GIS) to assess and predict the contamination potential of nitrate-N in the aquifer of Lanyang Plain, Taiwan. Seven factors of hydrogeology and hydrology, which includes seven parameters - Depth to groundwater, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone, and hydraulic Conductivity, are considered to carry out this assessment. The validity of the presented model is established by comparing the results with the measured nitrate concentration in wells within the study area. Adjusting factor weightings via the discriminant analysis is performed to improve the assessment and prediction. The analyzed results can provide residents with suggestive strategies against nitrate-N pollution in agricultural regions and government administrators with explicit information of Nitrate-N pollution extents when plans of water resources are considered.

  18. Dissipation of the herbicide oxyfluorfen in subtropical soils and its potential to contaminate groundwater.

    Science.gov (United States)

    Yen, Jui-Hung; Sheu, Wey-Shin; Wang, Yei-Shung

    2003-02-01

    The dissipation and mobility of the herbicide oxyfluorfen (2-chloro-alpha,alpha,alpha-trifluoro-p-tolyl 3-ethoxy-4-nitrophenyl ether) in field soil of Taiwan were investigated in the laboratory with six tea garden soils. The dissipation coefficients of oxyfluorfen in soils of different moisture content (30%, 60%, and 90% of soil field capacity) and soil temperature (10 degrees C, 25 degrees C, and 40 degrees C) were studied. Results indicate that the half-life of oxyfluorfen ranged from 72 to 160 days for six tea garden soils. It was found that if the temperature is high, the dissipation rate is rapid, and there is almost no dissipation at 10 degrees C. Possible contamination of groundwater by the herbicide oxyfluorfen was assessed using the behavior assessment model and the groundwater pollution-potential (GWP) model. The results obtained after evaluating the residue and travel time using the GWP model illustrated that oxyfluorfen is not very mobile in soil and may not contaminate groundwater under normal conditions. But in the case of soil of extremely low organic carbon content and coarse texture, oxyfluorfen has the potential to contaminate groundwater less than 3m deep.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-11-15

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

  20. Ranking harbours in the Maritime provinces of Canada for potential to contaminate American lobster (Homarus americanus) with polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Prouse, N.J. [Department of Fisheries and Oceans, Halifax, NS (Canada). Biological Sciences Branch

    1997-05-01

    The sources of polycyclic aromatic hydrocarbon (PAH) contamination within selected harbors in the Maritime provinces of Canada were evaluated by assessing point sources, population, industrial and commercial activity, international and domestic ship traffic, and the number of commercial fishing vessels. Results showed that Sydney ranked as the highest potential for PAH contamination. Ranking of the other Maritime harbors was also presented. The lobster contamination with PAHs was reviewed.

  1. First evidence of persistent organic contaminants as potential anthropogenic stressors in the Barndoor Skate Dipturus laevis.

    Science.gov (United States)

    Lyons, Kady; Adams, Douglas H

    2017-03-15

    Although exploited populations of elasmobranchs may be able to recover from fishing pressure, there is little information regarding the Barndoor Skate's ability to cope with other anthropogenic stressors such as organic contaminants (OCs). Legacy OCs were measured in liver, muscle and ova from fourteen Barndoor Skates with mature skates having significantly greater mean concentrations of OCs than immature skates, demonstrating bioaccumulation with age. Using Toxic Equivalency Factors, skates were found to have levels of PCBs that have been shown to elicit negative physiological responses in other fishes and these results highlight the need for future studies to investigate the potential impacts that bioaccumulated organic contaminants have on the recovery and conservation of this vulnerable species. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Phytostabilization potential of evening primrose (Oenothera glazioviana) for copper-contaminated sites.

    Science.gov (United States)

    Guo, Pan; Wang, Ting; Liu, Yanli; Xia, Yan; Wang, Guiping; Shen, Zhenguo; Chen, Yahua

    2014-01-01

    A field investigation, field experiment, and hydroponic experiment were conducted to evaluate feasibility of using Oenothera glazioviana for phytostabilization of copper-contaminated soil. In semiarid mine tailings in Tongling, Anhui, China, O. glazioviana, a copper excluder, was a dominant species in the community, with a low bioaccumulation factor, the lowest copper translocation factor, and the lowest copper content in seed (8 mg kg(-1)). When O. glazioviana was planted in copper-polluted farmland soil in Nanjing, Jiangsu, China, its growth and development improved and the level of γ-linolenic acid in seeds reached 17.1%, compared with 8.73% in mine tailings. A hydroponic study showed that O. glazioviana had high tolerance to copper, low upward transportation capacity of copper, and a high γ-linolenic acid content. Therefore, it has great potential for the phytostabilization of copper-contaminated soils and a high commercial value without risk to human health.

  3. Bioremediation potential of a tropical soil contaminated with a mixture of crude oil and production water.

    Science.gov (United States)

    Alvarez, Vanessa Marques; Santos, Silvia Cristina Cunha Dos Santos; Casella, Renata da Costa; Vital, Ronalt Leite; Sebastin, Gina Vasquez; Seldin, Lucy

    2008-12-01

    A typical tropical soil from the northeast of Brazil, where an important terrestrial oil field is located, was accidentally contaminated with a mixture of oil and saline production water. To study the bioremediation potential in this area, molecular methods based on PCR-DGGE were used to determine the diversity of the bacterial communities in bulk and in contaminated soils. Bacterial fingerprints revealed that the bacterial communities were affected by the presence of the mixture of oil and production water, and different profiles were observed when the contaminated soils were compared with the control. Halotolerant strains capable of degrading crude oil were also isolated from enrichment cultures obtained from the contaminated soil samples. Twenty-two strains showing these features were characterized genetically by amplified ribosomal DNA restriction analysis (ARDRA) and phenotypically by their colonial morphology and tolerance to high NaCl concentrations. Fifteen ARDRA groups were formed. Selected strains were analyzed by 16S rDNA sequencing, and Actinobacteria was identified as the main group found. Strains were also tested for their growth capability in the presence of different oil derivatives (hexane, dodecane, hexadecane, diesel, gasoline, toluene, naphthalene, o-xylene, and p-xylene) and different degradation profiles were observed. PCR products were obtained from 12 of the 15 ARDRA representatives when they were screened for the presence of the alkane hydroxylase gene (alkB). Members of the genera Rhodococcus and Gordonia were identified as predominant in the soil studied. These genera are usually implicated in oil degradation processes and, as such, the potential for bioremediation in this area can be considered as feasible.

  4. The potential of fruit trees to enhance converted habitats for migrating birds in southern Mexico

    Science.gov (United States)

    Foster, M.S.

    2007-01-01

    Migration routes used by Nearctic migrant birds can cover great distances; they also differ among species, within species, and between years and seasons. As a result, migration routes for an entire migratory avifauna can encompass broad geographic areas, making it impossible to protect continuous stretches of habitat sufficient to connect the wintering and breeding grounds for most species. Consequently, ways to enhance habitats converted for human use (i.e. for pasture, crop cultivation, human settlement) as stopover sites for migrants are especially important. Shelterbelts around pastures and fields, if planted with species targeted to support migrant (and resident) bird species that naturally occupy mature forest habitats and that are at least partially frugivorous, could be a powerful enhancement tool for such species, if the birds will enter the converted areas to feed. I tested this approach for Nearctic migrant birds during the spring migration through an area in Chiapas, Mexico. Mature forest tree species whose fruits are eaten by birds were surveyed. Based on life form, crop size and fruit characteristics, I selected three tree species for study: Cymbopetalum mayanum (Annonaceae), Bursera simaruba (Burseraceae) and Trophis racemosa (Moraceae). I compared the use of fruits of these species by migrants and residents in forest with their use of the fruits of isolated individuals of the same species in pasture and cropland. All three plant species were useful for enhancing converted habitats for forest-occupying spring migrants, although species differed in the degree to which they entered disturbed areas to feed on the fruits. These tree species could probably enhance habitats for migrants at sites throughout the natural geographic ranges of the plants; in other geographic areas for other target bird groups, other tree species might be more appropriate.

  5. MiR-203 controls proliferation, migration and invasive potential of prostate cancer cell lines

    DEFF Research Database (Denmark)

    Viticchiè, Giuditta; Lena, Anna Maria; Latina, Alessia

    2011-01-01

    Prostate cancers show a slow progression from a local lesion (primary tumor) to a metastatic and hormone-resistant phenotype. After an initial step of hyperplasia, in a high percentage of cases a neoplastic transformation event occurs that, less frequently, is followed by epithelial to mesenchymal...... cell lines compared to normal epithelial prostatic cells. Overexpression of miR-203 in brain or bone metastatic prostate cell lines (DU145 and PC3) is sufficient to induce a mesenchymal to epithelial transition with inhibition of cell proliferation, migration and invasiveness. We have identified CKAP2...

  6. HIV/AIDS-related sexual risk behaviors among rural residents in China: potential role of rural-to-urban migration

    Science.gov (United States)

    Li, Xiaoming; Zhang, Liying; Stanton, Bonita; Fang, Xiaoyi; Xiong, Qing; Lin, Danhua

    2007-01-01

    The relationship between rural-to-urban migration and the spread of HIV is well described, although most studies focus on sexual risk behaviors among rural-to-urban migrants at the urban destination areas. Few studies have examined the sexual risk behaviors of migrants who have returned from urban areas to their rural homes (“return migrants”) in comparison with those of local rural residents who have never migrated to cities (“non-migrants”). This study examines the potential association between rural-to-urban migration and sexual risk behaviors by comparing sexual risk behaviors between 553 return migrants and 441 non-migrants from same rural communities in China. Findings reveal that, after controlling for sociodemographic characteristics, return migrants in rural areas had higher levels of sexual risk, including unprotected sex, than non-migrants. Among return migrants, sexual risk behaviors were associated with age, gender, marital status, and number of different jobs they had previously held in the cities. These findings underscore the importance for HIV/AIDS education and prevention efforts targeting the migrant population in urban destinations as well as the return migrant population in rural areas. PMID:17967110

  7. Cancer-suppressive potential of extracts of endemic plant Helichrysum zivojinii: effects on cell migration, invasion and angiogenesis.

    Science.gov (United States)

    Matić, Ivana Z; Aljancić, Ivana; Vajs, Vlatka; Jadranin, Milka; Gligorijević, Nevenka; Milosavljević, Slobodan; Juranić, Zorica D

    2013-09-01

    Helichrysum zivojinii Cernjavski & Soska is an endemic plant species that grows in the National Park Galicica in Macedonia. Five extracts were isolated as fractions from the aerial parts of the plant: a n-hexane extract (1), a dichloromethane extract (2), an ethyl-acetate extract (3), a n-butanol extract (4) and a methanol extract (5). A dose-dependent cytotoxic activity of the extracts on MDA-MB-231 and EA.hy926 cells was observed. Extracts exhibited more pronounced cytotoxic actions on MDA-MB-231 cells than on EA.hy926 cells. The n-hexane extract (1), at a non-toxic concentration, exhibited an inhibitory effect on the migration as well the invasiveness of MDA-MB-231 cells. The dichloromethane extract (2), at a non-toxic concentration, demonstrated inhibition of MDA-MB-231 cells invasion. Each of the five extracts applied at non-toxic concentrations inhibited migration of EA.hy926 cells. The prominent inhibitory effect of the n-hexane extract on EA.hy926 cells migration was associated with a notable anti-angiogenic action of this extract. The other four tested extracts demonstrated mild anti-angiogenic activity. Our data highlight the prominent anticancer potential of n-hexane (1) and dichloromethane (2) extracts, which could be attributed to their very pronounced and selective cytotoxic activities as well as their anti-invasive and anti-angiogenic properties.

  8. Long term contaminant migration and impacts from uranium mill tailings. Comparison of computer models using a realistic dataset

    Energy Technology Data Exchange (ETDEWEB)

    Camus, H. [CEA Centre d' Etudes Nucleaires de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire] [and others

    1996-08-01

    This is the final report of the Working Group describing: the enhancement of the previously devised V1 scenario to produce a V2 scenario which includes more detailed source term and other site specific data; the application of models in deterministic and probabilistic mode to calculate contaminant concentrations in biosphere media, and related radiation doses, contaminant intakes and health risks, including estimates of uncertainties; the comparison and analysis of the resulting calculations. A series of scenarios was developed based on data provided by Working Group members from a range of actual tailings disposal sites, culminating in the V2.2 and V2.3 scenarios. The V2.2 and V2.3 scenarios are identical in all respects, except that the V2.2 considers radioactive (U-238 chain) contaminants, whilst the V2.3 considers stable elements (As, Ni, Pb). Since the scenarios are based on data obtained from a range of actual sites, they should be considered to be generically realistic rather than representative of a particular single site. In both scenarios, the contaminants of interest are assumed to be released in leachate from a tailings pile into an underlying aquifer. They are transported in groundwater through the aquifer to a well. Water is abstracted from the well and used for: watering beef cattle; human consumption; and irrigating leafy vegetables. The beef and leafy vegetables are consumed by humans living in the area. The same contaminants are also released into the atmosphere due to the wind erosion of the pile and then deposited upon the soil, pasture and leafy vegetables. In addition, for the V2.2 scenario, Rn-222 is assumed to be released to atmosphere from the pile. Unlike the V1 scenario, no consideration is given to surface water exposure pathways. Results show that there is exceedingly good agreement between participants' deterministic and probabilistic estimates of total dose or intake. They agree within a factor of two to three for both scenarios

  9. Long term contaminant migration and impacts from uranium mill tailings. Comparison of computer models using a realistic dataset

    International Nuclear Information System (INIS)

    Camus, H.

    1996-08-01

    This is the final report of the Working Group describing: the enhancement of the previously devised V1 scenario to produce a V2 scenario which includes more detailed source term and other site specific data; the application of models in deterministic and probabilistic mode to calculate contaminant concentrations in biosphere media, and related radiation doses, contaminant intakes and health risks, including estimates of uncertainties; the comparison and analysis of the resulting calculations. A series of scenarios was developed based on data provided by Working Group members from a range of actual tailings disposal sites, culminating in the V2.2 and V2.3 scenarios. The V2.2 and V2.3 scenarios are identical in all respects, except that the V2.2 considers radioactive (U-238 chain) contaminants, whilst the V2.3 considers stable elements (As, Ni, Pb). Since the scenarios are based on data obtained from a range of actual sites, they should be considered to be generically realistic rather than representative of a particular single site. In both scenarios, the contaminants of interest are assumed to be released in leachate from a tailings pile into an underlying aquifer. They are transported in groundwater through the aquifer to a well. Water is abstracted from the well and used for: watering beef cattle; human consumption; and irrigating leafy vegetables. The beef and leafy vegetables are consumed by humans living in the area. The same contaminants are also released into the atmosphere due to the wind erosion of the pile and then deposited upon the soil, pasture and leafy vegetables. In addition, for the V2.2 scenario, Rn-222 is assumed to be released to atmosphere from the pile. Unlike the V1 scenario, no consideration is given to surface water exposure pathways. Results show that there is exceedingly good agreement between participants' deterministic and probabilistic estimates of total dose or intake. They agree within a factor of two to three for both scenarios. Even

  10. Geology, geochemistry, and geophysics of the Fry Canyon uranium/copper project site, southeastern Utah - Indications of contaminant migration

    Science.gov (United States)

    Otton, James K.; Zielinski, Robert A.; Horton, Robert J.

    2010-01-01

    The Fry Canyon uranium/copper project site in San Juan County, southeastern Utah, was affected by the historical (1957-68) processing of uranium and copper-uranium ores. Relict uranium tailings and related ponds, and a large copper heap-leach pile at the site represent point sources of uranium and copper to local soils, surface water, and groundwater. This study was designed to establish the nature, extent, and pathways of contaminant dispersion. The methods used in this study are applicable at other sites of uranium mining, milling, or processing. The uranium tailings and associated ponds sit on a bench that is as much as 4.25 meters above the level of the adjacent modern channel of Fry Creek. The copper heap leach pile sits on bedrock just south of this bench. Contaminated groundwater from the ponds and other nearby sites moves downvalley and enters the modern alluvium of adjacent Fry Creek, its surface water, and also a broader, deeper paleochannel that underlies the modern creek channel and adjacent benches and stream terraces. The northern extent of contaminated groundwater is uncertain from geochemical data beyond an area of monitoring wells about 300 meters north of the site. Contaminated surface water extends to the State highway bridge. Some uranium-contaminated groundwater may also enter underlying bedrock of the Permian Cedar Mesa Sandstone along fracture zones. Four dc-resistivity surveys perpendicular to the valley trend were run across the channel and its adjacent stream terraces north of the heap-leach pile and ponds. Two surveys were done in a small field of monitoring wells and two in areas untested by borings to the north of the well field. Bedrock intercepts, salt distribution, and lithologic information from the wells and surface observations in the well field aided interpretation of the geophysical profiles there and allowed interpretation of the two profiles not tested by wells. The geophysical data for the two profiles to the north of the

  11. Analyzing potential effects of migration on coastal resource conservation in Southeastern Ghana.

    Science.gov (United States)

    Goldbach, Carina; Schlüter, Achim; Fujitani, Marie

    2018-03-01

    Coastal areas are under increasing pressure from rapid human population growth, yet empirical research on the effect of migration on coastal and marine resources is scarce. We contribute to this understudied literature by conducting an original household survey in a coastal region of Southeastern Ghana. This study employs two proxies for pro-environmental behavior that have not, to our knowledge, been used in the context of coastal migration, to explicitly compare migrant and non-migrant populations. Environmental attitudes toward coastal resources and individual extraction behavior in common-pool resource (CPR) experiments have shown broad relevance in the literature to understand natural resource decision making. We found that migrants in general did not differ significantly from non-migrants in relation to their environmental attitudes or their extraction behavior in the CPR game. However, when focusing on migrant fishers only, results suggested that this subgroup was less concerned about the utilization of coastal resources than non-migrant fishers and behaved less cooperatively in the CPR experiment. These findings, though, held true only for the subgroup of fishers, and could not be found for other occupational groups. Therefore, we conclude that migrants do not per se value coastal resources less or cooperate less in CPR situations, but that socioeconomic characteristics, and particularly their occupational status and their relation to the resource, matter. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Mapping subsurface pathways for contaminant migration at a proposed low level waste disposal site using electromagnetic methods

    International Nuclear Information System (INIS)

    Pin, F.G.; Ketelle, R.H.

    1984-01-01

    Electromagnetic methods have been used to measure apparent terrain conductivity in the downstream portion of a watershed in which a waste disposal site is proposed. At that site, the pathways for waste migration in ground water are controlled by subsurface channels. The channels are identified using isocurves of measured apparent conductivity. Two upstream channel branches are found to merge into a single downstream channel which constitutes the main drainage path out of the watershed. The identification and mapping of the ground water pathways is an important contribution to the site characterization study and the pathways analysis. The direct applications of terrain conductivity mapping to the planning of the monitoring program, the hydrogeological testing, and the modeling study are demonstrated. 7 references, 4 figures

  13. Conceptual Models for Migration of Key Groundwater Contaminants Through the Vadose Zone and Into the Upper Unconfined Aquifer Below the B-Complex

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R. Jeffrey; Bjornstad, Bruce N.; Keller, Jason M.; Thorne, Paul D.; Lanigan, David C.; Christensen, J. N.; Thomas, Gregory S.

    2010-07-01

    The B-Complex contains 3 major crib and trench disposal sites and 3 SST farms that have released nearly 346 mega-liters of waste liquids containing the following high groundwater risk drivers: ~14,000 kg of CN, 29,000 kg of Cr, 12,000 kg of U and 145 Ci of Tc-99. After a thorough review of available vadose zone sediment and pore water, groundwater plume, field gamma logging, field electrical resistivity studies, we developed conceptual models for which facilities have been the significant sources of the contaminants in the groundwater and estimated the masses of these contaminants remaining in the vadose zone and currently present in the groundwater in comparison to the totals released. This allowed us to make mass balance calculations on how consistent our knowledge is on the current deep vadose zone and groundwater distribution of contaminants. Strengths and weaknesses of the conceptual models are discussed as well as implications on future groundwater and deep vadose zone remediation alternatives. Our hypothesized conceptual models attribute the source of all of the cyanide and most of the Tc-99 currently in the groundwater to the BY cribs. The source of the uranium is the BX-102 tank overfill event and the source of most of the chromium is the B-7-A&B and B-8 cribs. Our mass balance estimates suggest that there are much larger masses of U, CN, and Tc remaining in the deep vadose zone within ~20 ft of the water table than is currently in the groundwater plumes below the B-Complex. This hypothesis needs to be carefully considered before future remediation efforts are chosen. The masses of these groundwater risk drivers in the the groundwater plumes have been increasing over the last decade and the groundwater plumes are migrating to the northwest towards the Gable Gap. The groundwater flow rate appears to flucuate in response to seasonal changes in hydraulic gradient. The flux of contaminants out of the deep vadose zone from the three proposed sources also

  14. Generic Assessment Criteria for human health risk assessment of potentially contaminated land in China.

    Science.gov (United States)

    Cheng, Yuanyuan; Nathanail, Paul C

    2009-12-20

    Generic Assessment Criteria (GAC) are derived using widely applicable assumptions about the characteristics and behaviour of contaminant sources, pathways and receptors. GAC provide nationally consistent guidance, thereby saving money and time. Currently, there are no human health based Generic Assessment Criteria (GAC) for contaminated sites in China. Protection of human health is therefore difficult to ensure and demonstrate; and the lack of GAC makes it difficult to tell if there is potential significant risk to human health unless site-specific criteria are derived. This paper derived Chinese GAC (GAC) for five inorganic and eight organic substances for three regions in China for three land uses: urban residential without plant uptake, Chinese cultivated land, and commercial/industrial using the SNIFFER model. The SNIFFER model has been further implemented with a dermal absorption algorithm and the model default input values have been changed to reflect the Chinese exposure scenarios. It is envisaged that the modified SNIFFER model could be used to derive GAC for more contaminants, more Regions, and more land uses. Further research to enhance the reliability and acceptability of the GAC is needed in regional/national surveys in diet and working patterns.

  15. Toxicological benchmarks for screening potential contaminants of concern for effects on sediment-associated biota

    International Nuclear Information System (INIS)

    Hull, R.N.; Suter, G.W. II.

    1993-08-01

    Because a hazardous waste site may contain hundreds of chemicals, it is important to screen contaminants of concern for the ecological risk assessment. Often this screening is done as part of a Screening Assessment, the purpose of which is to evaluate the available data, identify data gaps, and screen potential contaminants of concern. Screening may be accomplished by using a set of toxicological benchmarks. These benchmarks are helpful in determining whether contaminants warrant further assessment or are at a level that requires no further attention. If a chemical concentration or the reported detection limit exceeds a proposed lower benchmark, more analysis is needed to determine the hazards posed by that chemical. If, however, the chemical concentration falls below the lower benchmark value, the chemical may be eliminated from further study. This report briefly describes three categories of approaches to the development of sediment quality benchmarks. These approaches are based on analytical chemistry, toxicity test results, and field survey data. A fourth integrative approach incorporates all three types of data

  16. Potential reuse of petroleum-contaminated soil: A directory of permitted recycling facilities

    International Nuclear Information System (INIS)

    Rosenthal, S.; Wolf, G.; Avery, M.; Nash, J.H.

    1992-06-01

    Soil contaminated by virgin petroleum products leaking from underground storage tanks is a pervasive problem in the United States. Economically feasible disposal of such soil concerns the responsible party (RP), whether the RP is one individual small business owner, a group of owners, or a large multinational corporation. They may need a starting point in their search for an appropriate solution, such as recycling. The report provides initial assistance in two important areas. First it discusses four potential recycling technologies that manufacture marketable products from recycled petroleum-contaminated soil: the hot mix asphalt process, the cold mix asphalt system, cement production, and brick manufacturing. The report also presents the results of a project survey designed to identify recycling facilities. It lists recycling facilities alphabetically by location within each state, organized by U.S. Environmental Protection Agency (EPA) Region. The report also includes detailed addresses, recycling locations, telephone numbers, and contacts for these facilities. The scope of the project limits listings to fixed facilities or small mobile facility owners that recycle soil contaminated by virgin petroleum products into marketable commodities. It does not address site-specific or commercial hazardous waste remediation facilities

  17. Cadmium content of commercial and contaminated rice, Oryza sativa, in Thailand and potential health implications.

    Science.gov (United States)

    Zwicker, R; Promsawad, A; Zwicker, B M; Laoharojanaphand, S

    2010-03-01

    Thailand is the number one global exporter and among the top five producers of rice in the world. A significant increase in anthropogenic contamination in agricultural soils over the past few decades has lead to concerns with cadmium and its uptake in rice. The cadmium levels in Thai rice from different sources/areas were determined and used to estimate the potential health risks to consumers. The cadmium concentration in the commercial rice samples ranged from below the detection limit to 0.016 mg/kg. The cadmium concentrations in the contaminated rice samples ranged from a low of 0.007 mg/kg to a high of 0.579 mg/kg. Five of the calculated values exceed the proposed PTWI, with one value almost three times higher and two values almost double. The three highly elevated values are certainly a concern from a health standpoint. Ultimately, action is required to address the health implications resulting from the cadmium contamination in agricultural soils used for rice production in a few select areas of Thailand. Overall, this study indicates that the vast majority of rice produced, consumed and exported by Thailand is safe pertaining to cadmium content.

  18. Comparison of phytoremediation potential of three grass species in soil contaminated with cadmium

    Directory of Open Access Journals (Sweden)

    Gołda Sylwia

    2016-03-01

    Full Text Available The aim of the study was to compare the toleration of Poa pratensis, Lolium perenne and Festuca rubra to cadmium contamination as well as the phytoremediation potential of these three species of grass. The pot experiment was conducted in four replications in pots containing 2.0 kg of soil. The soil was contaminated with three doses of Cd – 30, 60 and 120 mg·kg−1. After two months, the aerial parts of plants were harvested. The roots were dug up, brushed off from the remaining soil and washed with water. The biomass was defined and the cadmium concentration was determined in aerial parts and roots. The phytoremediation potential of grasses was evaluated using biomass of grasses, bioaccumulation factor (BF and translocation factor (TF. All three tested species of grasses had TF 1. It indicates their suitability for phytostabilisation and makes them unsuitable for phytoextraction of Cd from the soil. Comparing the usefulness of the tested grasses for phytoremediation has shown that the phytostabilisation potential of P. pratensis was lower than that of L. perenne and F. rubra. P. pratensis was distinguished by higher TF, smaller root biomass and lower tolerance for Cd excess in the soil in comparison with the two other test grasses. At the same time, L. perenne was characterised by the smallest decrease in biomass and the largest Cd accumulation in roots at the lowest dose of Cd. It indicates good usefulness for phytostabilisation of soils characterised by a relatively small pollution by cadmium.

  19. Resistivity profiling for mapping gravel layers that may control contaminant migration at the Amargosa Desert Research Site, Nevada

    Science.gov (United States)

    Lucius, Jeffrey E.; Abraham, Jared D.; Burton, Bethany L.

    2008-01-01

    Gaseous contaminants, including CFC 113, chloroform, and tritiated compounds, move preferentially in unsaturated subsurface gravel layers away from disposal trenches at a closed low-level radioactive waste-disposal facility in the Amargosa Desert about 17 kilometers south of Beatty, Nevada. Two distinct gravel layers are involved in contaminant transport: a thin, shallow layer between about 0.5 and 2.2 meters below the surface and a layer of variable thickness between about 15 and 30 meters below land surface. From 2003 to 2005, the U.S. Geological Survey used multielectrode DC and AC resistivity surveys to map these gravel layers. Previous core sampling indicates the fine-grained sediments generally have higher water content than the gravel layers or the sediments near the surface. The relatively higher electrical resistivity of the dry gravel layers, compared to that of the surrounding finer sediments, makes the gravel readily mappable using electrical resistivity profiling. The upper gravel layer is not easily distinguished from the very dry, fine-grained deposits at the surface. Two-dimensional resistivity models, however, clearly identify the resistive lower gravel layer, which is continuous near the facility except to the southeast. Multielectrode resistivity surveys provide a practical noninvasive method to image hydrogeologic features in the arid environment of the Amargosa Desert.

  20. Potential effects of groundwater and surface water contamination in an urban area, Qus City, Upper Egypt

    Science.gov (United States)

    Abdalla, Fathy; Khalil, Ramadan

    2018-05-01

    The potential effects of anthropogenic activities, in particular, unsafe sewage disposal practices, on shallow groundwater in an unconfined aquifer and on surface water were evaluated within an urban area by the use of hydrogeological, hydrochemical, and bacteriological analyses. Physicochemical and bacteriological data was obtained from forty-five sampling points based on33 groundwater samples from variable depths and 12 surface water samples. The pollution sources are related to raw sewage and wastewater discharges, agricultural runoff, and wastewater from the nearby Paper Factory. Out of the 33 groundwater samples studied, 17 had significant concentrations of NO3-, Cl- and SO42-, and high bacteria counts. Most of the water samples from the wells contained high Fe, Mn, Pb, Zn, Cd, and Cr. The majority of surface water samples presented high NO3- concentrations and high bacteria counts. A scatter plot of HCO3- versus Ca indicates that 58% of the surface water samples fall within the extreme contamination zone, while the others are within the mixing zone; whereas 94% of groundwater samples showed evidence of mixing between groundwater and wastewater. The bacteriological assessment showed that all measured surface and groundwater samples contained Escherichia coli and total coliform bacteria. A risk map delineated four classes of contamination, namely, those sampling points with high (39.3%), moderate (36.3%), low (13.3%), and very low (11.1%) levels of contamination. Most of the highest pollution points were in the middle part of the urban area, which suffers from unmanaged sewage and industrial effluents. Overall, the results demonstrate that surface and groundwater in Qus City are at high risk of contamination by wastewater since the water table is shallow and there is a lack of a formal sanitation network infrastructure. The product risk map is a useful tool for prioritizing zones that require immediate mitigation and monitoring.

  1. Toxicological benchmarks for screening potential contaminants of concern for effects on aquatic biota: 1996 revision

    Energy Technology Data Exchange (ETDEWEB)

    Suter, G.W. II [Oak Ridge National Lab., TN (United States); Tsao, C.L. [Duke Univ., Durham, NC (United States). School of the Environment

    1996-06-01

    This report presents potential screening benchmarks for protection of aquatic life form contaminants in water. Because there is no guidance for screening for benchmarks, a set of alternative benchmarks is presented herein. This report presents the alternative benchmarks for chemicals that have been detected on the Oak Ridge Reservation. It also presents the data used to calculate the benchmarks and the sources of the data. It compares the benchmarks and discusses their relative conservatism and utility. Also included is the updates of benchmark values where appropriate, new benchmark values, secondary sources are replaced by primary sources, and a more complete documentation of the sources and derivation of all values are presented.

  2. Microbial Detoxification of Bifenthrin by a Novel Yeast and Its Potential for Contaminated Soils Treatment

    OpenAIRE

    Chen, Shaohua; Luo, Jianjun; Hu, Meiying; Geng, Peng; Zhang, Yanbo

    2012-01-01

    Bifenthrin is one the most widespread pollutants and has caused potential effect on aquatic life and human health, yet little is known about microbial degradation in contaminated regions. A novel yeast strain ZS-02, isolated from activated sludge and identified as Candida pelliculosa based on morphology, API test and 18S rDNA gene analysis, was found highly effective in degrading bifenthrin over a wide range of temperatures (20-40 °C) and pH (5-9). On the basis of response surface methodology...

  3. Potential role of insulin signaling on vascular smooth muscle cell migration, proliferation, and inflammation pathways.

    Science.gov (United States)

    Cersosimo, Eugenio; Xu, Xiaojing; Musi, Nicolas

    2012-02-15

    To investigate the role of insulin signaling pathways in migration, proliferation, and inflammation of vascular smooth muscle cells (VSMCs), we examined the expression of active components of the phosphatidyl inositol 3 (PI-3) kinase (p-Akt) and mitogen-activated protein kinase (MAPK) (p-Erk) in primary cultures of VSMCs from human coronary arteries. VSMCs were treated in a dose-response manner with insulin (0, 1, 10, and 100 nM) for 20 min, and Akt and Erk phosphorylation were measured by Western blot analysis. In separate experiments, we evaluated the effect of 200 μM palmitate, in the presence and absence of 8 μM pioglitazone, on insulin-stimulated (100 nM for 20 min) Akt and Erk phosphorylation. The phosphorylation of Akt and Erk in VSMCs exhibited a dose dependency with a three- to fourfold increase, respectively, at the highest dose (100 nM). In the presence of palmitate, insulin-induced Akt phosphorylation was completely abolished, and there was a threefold increase in p-Erk. With addition of pioglitazone, the phosphorylation of Akt by insulin remained unchanged, whereas insulin-stimulated Erk phosphorylation was reduced by pioglitazone. These data in VSMCs indicate that high palmitate decreases insulin-stimulated Akt phosphorylation and stimulates MAPK, whereas preexposure peroxisome proliferator-activated receptor-γ agonist pioglitazone preserves Akt phosphorylation and simultaneously attenuates MAPK signaling. Our results suggest that metabolic and mitogenic insulin signals have different sensitivity, are independently regulated, and may play a role in arterial smooth muscle cells migration, proliferation, and inflammation in conditions of acute hyperinsulinemia.

  4. Application of airborne photogrammetry for the visualisation and assessment of contamination migration arising from a Fukushima waste storage facility.

    Science.gov (United States)

    Connor, D T; Martin, P G; Smith, N T; Payne, L; Hutson, C; Payton, O D; Yamashiki, Y; Scott, T B

    2018-03-01

    Airborne systems such as lightweight and highly portable unmanned aerial vehicles (UAVs) are becoming increasingly widespread in both academia and industry - with an ever-increasing range of applications, including (but not limited to), air quality sampling, wildlife monitoring and land-use mapping. In this work, high-resolution airborne photogrammetry obtained using a multi-rotor system operating at low survey altitudes, is combined with ground-based radiation mapping data acquired at an interim storage facility for wastes removed as part of the large-scale Fukushima clean-up program. The investigation aimed to assess the extent to which the remediation program at a specific site has contained the stored contaminants, as well as present a new methodology for rapidly surveying radiological sites globally. From the three-dimensional rendering of the site of interest, it was possible to not only generate a powerful graphic confirming the elevated radiological intensity existing at the location of the waste bags, but also to also illustrate the downslope movement of contamination due to species leakage from the large 1m 3 storage bags. The entire survey took less than 1 h to perform, and was subsequently post-processed using graphical information software to obtain the renderings. The conclusions within this study not only highlight the usefulness of incorporating three-dimensional renderings within radiation mapping protocols, but also conclude that current methods of monitoring these storage facilities in the long term could be improved through the integration of UAVs within the standard protocol. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Potential of the Galega – Rhizobium galegae System for Bioremediation of Oil-Contaminated Soil

    Directory of Open Access Journals (Sweden)

    Minna M. Jussila

    2003-01-01

    Full Text Available Bioremediation potential of the nitrogen-fixing leguminous plant Galega orientalis Lam. and its microsymbiont Rhizobium galegae was evaluated in microcosm and mesocosm scale in oil and BTEX (benzene, toluene, ethylbenzene, xylene contaminated soils, with m-toluate serving as a model for the latter group. G. orientalis and Rhizobium galegae remained viable in m-toluate fractions up to 3000 ppm. Plant growth and nodulation were inhibited in 500 ppm m-toluate, but were restored when plants were transferred to clean medium. In soil, G. orientalis nodulated and showed good growth in 2000 ppm m-toluate as well as in diesel-contaminated soil in the field, where the plant was stimulating bacterial growth in the rhizosphere. A collection of 52 indigenous m-toluate-tolerating bacteria isolated from oil-contaminated rhizosphere of G. orientalis was characterised and identified by classical and molecular biological methods. 16SrDNA PCR-RFLP and (GTG5-PCR genomic fingerprinting combined with partial sequencing indicated the presence of five major lineages of the Bacteria domain. A TOL plasmid-specific xylE-PCR was developed in order to detect both active and potential degraders of m-toluate. The ability to degrade m-toluate in the presence of the gene xylE was detected only within the genus Pseudomonas. The isolates were tested for capacity to grow on m-toluate as their sole carbon and energy source. In laboratory experiments, the best rhizosphere isolates performed equally well to the positive control strain and are good candidates for inoculant production in the future. They have been tagged with marker genes for further studies on colonisation and persistence.

  6. Potential of vetiver (vetiveria zizanioides l.) grass in removing selected pahs from diesel contaminated soil

    International Nuclear Information System (INIS)

    Nisa, W.U.; Rashid, A.

    2015-01-01

    Phytoremediation has been renowned as an encouraging technology for the remediation of polycyclic aromatic hydrocarbon (PAH)-contaminated soils, little is known about how plant species behave during the process of PAH phytoremediation. Therefore, the aim of this study was to investigate the effectiveness of vetiver (Vetiveria zizanioides L.) plant in PAH phytoremediation and extraction potential of Vetiveria zizanioides for selected PAHs from the diesel contaminated soil. The field soil samples were spiked with varying concentrations (0.5% and 1%) of diesel and used for pot experiment which was conducted in greenhouse. Vetiver grass was used as experimental plant. Physico-chemical analysis of soil was performed before and after the experiment. Concentration of selected PAHs i.e. phenanthrene, pyrene and benzo(a)pyrene in soil was determined using HPLC. Plant parameters such as root/shoot length and dry mass were compared after harvest. Concentrations of PAHs were also determined in plant material and in soils after harvesting. Result showed that initial concentration of phenanthrene was significantly different from final concentration in treatments in which soil was spiked with diesel. Initial and final concentration of pyrene in soil was also significantly different from each other in two treatments in which soil was spiked with 1% diesel. Pyrene concentration was significantly different in roots and shoots of plants while benzo(a)pyrene concentration in treatments in which soil was spiked with diesel was also significantly different from roots and shoots. Phenanthrene was less extracted by the plant in all the treatments and it was present in higher concentration in soil as compared to plant. Our results indicate that vetiver grass has effectively removed PAHs from soil consequently a significantly higher root and shoot uptake of PAHs was observed than control treatments. Study concludes Vetiveria zizanioides as potentially promising plant specie for the removal

  7. Methodological guide: management of industrial sites potentially contaminated by radioactive substances; Guide methodologique: gestion des sites industriels potentiellement contamines par des substances radioactives

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    At the request of the Ministries of Health and the Environment, IPSN is preparing and publishing the first version of the methodological guide devoted to managing industrial sites potentially contaminated by radioactive substances. This guide describes a procedure for defining and choosing strategies for rehabilitating such industrial sites. (author)

  8. A decision tree approach to screen drinking water contaminants for multiroute exposure potential in developing guideline values.

    Science.gov (United States)

    Krishnan, Kannan; Carrier, Richard

    2017-07-03

    The consideration of inhalation and dermal routes of exposures in developing guideline values for drinking water contaminants is important. However, there is no guidance for determining the eligibility of a drinking water contaminant for its multiroute exposure potential. The objective of the present study was to develop a 4-step framework to screen chemicals for their dermal and inhalation exposure potential in the process of developing guideline values. The proposed framework emphasizes the importance of considering basic physicochemical properties prior to detailed assessment of dermal and inhalation routes of exposure to drinking water contaminants in setting guideline values.

  9. Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China

    International Nuclear Information System (INIS)

    Shi Guitao; Chen Zhenlou; Xu Shiyuan; Zhang Ju; Wang Li; Bi Chunjuan; Teng Jiyan

    2008-01-01

    A detailed investigation was conducted to understand the contamination characteristics of a selected set of potentially toxic metals in Shanghai. The amount of Pb, Zn, Cu, Cr, Cd and Ni were determined from 273 soil/dust samples collected within urban area. The results indicated that concentration of all metals except Ni in soils was significant, and metal pollution was even severer in roadside dust. A series of metal spatial distribution maps were created through geostatistical analysis, and the pollution hotspots tended to associate with city core area, major road junctions, and the regions close to industrial zones. In attempt of identifying the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Pb, Zn and Cu mainly originated from traffic contaminants; soil Ni was associated with natural concentration; Cd largely came from point-sourced industrial pollution; and Cr, Ni in dust were mainly related to atmospheric deposition. - Human activities have led to high accumulation of potentially toxic metals in urban soils and roadside dust of Shanghai

  10. Potentially toxic metal contamination of urban soils and roadside dust in Shanghai, China

    Energy Technology Data Exchange (ETDEWEB)

    Shi Guitao [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Chen Zhenlou [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China)], E-mail: gt_shi@163.com; Xu Shiyuan [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Zhang Ju [School of Environment and Planning, Liaocheng University, Liaocheng 252059 (China); Wang Li; Bi Chunjuan [Key Laboratory of Geographic Information Science of Ministry of Education, East China Normal University, Shanghai 200062 (China); Teng Jiyan [Shanghai Chongming Dongtan National Nature Reserve, Shanghai 202183 (China)

    2008-11-15

    A detailed investigation was conducted to understand the contamination characteristics of a selected set of potentially toxic metals in Shanghai. The amount of Pb, Zn, Cu, Cr, Cd and Ni were determined from 273 soil/dust samples collected within urban area. The results indicated that concentration of all metals except Ni in soils was significant, and metal pollution was even severer in roadside dust. A series of metal spatial distribution maps were created through geostatistical analysis, and the pollution hotspots tended to associate with city core area, major road junctions, and the regions close to industrial zones. In attempt of identifying the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Pb, Zn and Cu mainly originated from traffic contaminants; soil Ni was associated with natural concentration; Cd largely came from point-sourced industrial pollution; and Cr, Ni in dust were mainly related to atmospheric deposition. - Human activities have led to high accumulation of potentially toxic metals in urban soils and roadside dust of Shanghai.

  11. Toxicological benchmarks for screening contaminants of potential concern for effects on freshwater biota

    International Nuclear Information System (INIS)

    Suter, G.W. II

    1996-01-01

    An important early step in the assessment of ecological risks at contaminated sites is the screening of chemicals detected on the site to identify those that constitute a potential risk. Part of this screening process is the comparison of measured ambient concentrations to concentrations that are believed to be nonhazardous, termed benchmarks. This article discusses 13 methods by which benchmarks may be derived for aquatic biota and presents benchmarks for 105 chemicals. It then compares them with respect to their sensitivity, availability, magnitude relative to background concentrations, and conceptual bases. This compilation is limited to chemicals that have been detected on the US Department of Energy's Oak Ridge Reservation (ORR) and to benchmarks derived from studies of toxic effects on freshwater organisms. The list of chemicals includes 45 metals and 56 industrial organic chemicals but only four pesticides. Although some individual values can be shown to be too high to be protective and others are too low to be useful for screening, none of the approaches to benchmark derivation can be rejected without further definition of what constitutes adequate protection. The most appropriate screening strategy is to use multiple benchmark values along with background concentrations, knowledge of waste composition, and physicochemical properties to identify contaminants of potential concern

  12. Child's play : investigating the exposure potential of environmental contaminants in soil

    International Nuclear Information System (INIS)

    Pearce, D.C.; Dowling, K.; Waldron, H.; Garnett, D.

    2005-01-01

    Arsenic and chromium have been identified as soil contaminants from smelting, industrial and mining activities. The potential for human uptake of these elements from soil has been established with highest concentrations found in children, who are particularly susceptible to environmental exposure. This study explores the exposure potential of selected soil trace elements in rural Victoria, Australia, by investigating the relationship between uptake, measured using toenail clippings as the biomarker of exposure, and soil concentrations in two communities: one near current and historic gold mining, the other an agricultural community. We report the preliminary findings of a cross-sectional survey, in which toenail clippings were obtained from 12 children in the former community, and 16 children in the latter. (author). 26 refs., 3 tabs

  13. Multisite Direct Determination of the Potential for Environmental Contamination of Urine Samples Used for Diagnosis of Sexually Transmitted Infections.

    Science.gov (United States)

    Andersson, Patiyan; Tong, Steven Y C; Lilliebridge, Rachael A; Brenner, Nicole C; Martin, Louise M; Spencer, Emma; Delima, Jennifer; Singh, Gurmeet; McCann, Frances; Hudson, Carolyn; Johns, Tracy; Giffard, Philip M

    2014-09-01

    The detection of a sexually transmitted infection (STI) agent in a urine specimen from a young child is regarded as an indicator of sexual contact. False positives may conceivably arise from the transfer of environmental contaminants in clinic toilet or bathroom facilities into urine specimens. The potential for contamination of urine specimens with environmental STI nucleic acid was tested empirically in the male and female toilets or bathrooms at 10 Northern Territory (Australia) clinics, on 7 separate occasions at each. At each of the 140 experiments, environmental contamination with Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis nucleic acid contamination was determined by swabbing 10 locations, and urine collection was simulated 5 times, using a (1) synthetic urine surrogate and (2) a standardized finger contamination procedure. The most contaminated toilets and bathrooms were in remote Indigenous communities. No contamination was found in the Northern Territory Government Sexual Assault Referral Centre clinics, and intermediate levels of contamination were found in sexual health clinics and in clinics in regional urban centres. The frequency of surrogate urine sample contamination was low but non-zero. For example, 4 of 558 of the urine surrogate specimens from remote clinics were STI positive. This is by far the largest study addressing the potential environmental contamination of urine samples with STI agents. Positive STI tests arising from environmental contamination of urine specimens cannot be ruled out. The results emphasize that urine specimens from young children taken for STI testing should be obtained by trained staff in clean environments, and duplicate specimens should be obtained if possible. © The Author 2013. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society.

  14. Identification of SEC62 as a potential marker for 3q amplification and cellular migration in dysplastic cervical lesions

    International Nuclear Information System (INIS)

    Linxweiler, Maximilian; Bochen, Florian; Schick, Bernhard; Wemmert, Silke; Al Kadah, Basel; Greiner, Markus; Hasenfus, Andrea; Bohle, Rainer-Maria; Juhasz-Böss, Ingolf; Solomayer, Erich-Franz; Takacs, Zoltan Ferenc

    2016-01-01

    Chromosome 3 amplification affecting the 3q26 region is a common genomic alteration in cervical cancer, typically marking the transition of precancerous intraepithelial lesions to an invasive phenotype. Though potential 3q encoded target genes of this amplification have been identified, a functional correlation of potential oncogenic function is still missing. In this study, we investigated copy number changes and the expression level of SEC62 encoded at 3q26.2 as a new potential 3q oncogene in dysplastic cervical lesions and analyzed its role in cervical cancer cell biology. Expression levels of Sec62 and vimentin were analyzed in liquid based cytology specimens from 107 women with varying grades of cervical dysplasia ranging from normal cases to cancer by immunofluorescence cytology. Additionally, a subset of 20 representative cases was used for FISH analyses targeting SEC62. To further explore the functional role of Sec62 in cervical cancer, HeLa cells were transfected with a SEC62 plasmid or SEC62 siRNA and analyzed for their proliferation and migration potential using real-time monitoring and trans-well systems as well as changes in the expression of EMT markers. FISH analyses of the swabbed cells showed a rising number of SEC62 gains and amplifications correlating to the grade of dysplasia with the highest incidence in high grade squamous intraepithelial lesions and squamous cell carcinomas. When analyzing the expression level of Sec62 and vimentin, we found a gradually increasing expression level of both proteins according to the severity of the dysplasia. In functional analyses, SEC62 silencing inhibited and SEC62 overexpression stimulated the migration of HeLa cells with only marginal effects on cell proliferation, the expression level of EMT markers and the cytoskeleton structure. Our study suggests SEC62 as a target gene of 3q26 amplification and a stimulator of cellular migration in dysplastic cervical lesions. Hence, SEC62 could serve as a potential

  15. Overview of Macrophage Migration Inhibitory Factor (MIF as a Potential Biomarker Relevant to Adiposity

    Directory of Open Access Journals (Sweden)

    Jun Nishihira

    2012-07-01

    Full Text Available The cytokine “macrophage migration inhibitory factor (MIF” is generally recognized as a proinflammatory cytokine, and MIF is involved in broad range of acute and chronic inflammatory states. With regard to glucose metabolism and insulin secretion, MIF is produced by pancreatic β cells and acts as a positive regulator of insulin secretion. In contrast, it is evident that MIF expressed in adipose tissues causes insulin resistance. Concerning MIF gene analysis, we found four alleles: 5-, 6-, 7-and 8-CATT at position −794 of MIF gene in a Japanese population. Genotypes without the 5-CATT allele were more common in the obese subjects than in the lean or overweight groups. It is conceivable that promoter polymorphism in the MIF gene is profoundly linked with obesity relevant to lifestyle diseases, such as diabetes. Obesity has become a serious social issue due to the inappropriate nutritional balance, and the consumption of functional foods (including functional foods to reduce fat mass is expected to overcome this issue. In this context, MIF would be a reliable quantitative biomarker to evaluate the effects of functional foods on adiposity.

  16. Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

    Energy Technology Data Exchange (ETDEWEB)

    Aponte, C.I.

    2000-02-17

    F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events.

  17. Dose potential of sludge contaminated and/or TRU contaminated waste in B-25s for tornado and straight wind events

    International Nuclear Information System (INIS)

    Aponte, C.I.

    2000-01-01

    F and H Tank Farms generate supernate and sludge contaminated Low-Level Waste. The waste is collected, characterized, and packaged for disposal. Before the waste can be disposed of, however, it must be properly characterized. Since the radionuclide distribution in typical supernate is well known, its characterization is relatively straight forward and requires minimal effort. Non-routine waste, including potentially sludge contaminated, requires much more effort to effectively characterize. The radionuclide distribution must be determined. In some cases the waste can be contaminated by various sludge transfers with unique radionuclide distributions. In these cases, the characterization can require an extensive effort. Even after an extensive characterization effort, the container must still be prepared for shipping. Therefore a significant amount of time may elapse from the time the waste is generated until the time of disposal. During the time it is possible for a tornado or high wind scenario to occur. The purpose of this report is to determine the effect of a tornado on potential sludge contaminated waste, or Transuranic (TRU) waste in B-25s [large storage containers], to evaluate the potential impact on F and H Tank Farms, and to help establish a B-25 control program for tornado events

  18. PAHs contamination in urban soils from Lisbon: spatial variability and potential risks

    Science.gov (United States)

    Cachada, Anabela; Pereira, Ruth; Ferreira da Silva, Eduardo; Duarte, Armando

    2015-04-01

    Polycyclic Aromatic hydrocarbons (PAHs) can become major contaminants in urban and industrial areas, due to the existence of a plethora of diffuse and point sources. Particularly diffuse pollution, which is normally characterized by continuous and long-term emission of contaminants below risk levels, can be a major problem in urban areas. Since PAHs are persistent and tend to accumulate in soils, levels are often above the recommended guidelines indicating that ecological functions of soils may be affected. Moreover, due to the lipophilic nature, hydrophobicity and low chemical and biological degradation rates of PAHs, which leads to their bioconcentration and bioamplification, they may reach toxicological relevant concentrations in organisms. The importance and interest of studying this group of contaminants is magnified due to their carcinogenic, mutagenic and endocrine disrupting effects. In this study, a risk assessment framework has been followed in order to evaluate the potential hazards posed by the presence of PAHs in Lisbon urban soils. Hence, the first step consisted in screening the total concentrations of PAHs followed by the calculation of risks based on existing models. Considering these models several samples were identified as representing a potential risk when comparing with the guidelines for soil protection. Moreover, it was found that for 38% of samples more than 50% of species can be potentially affected by the mixture of PAHs. The use of geostatistical methods allowed to visualize the predicted distribution of PAHs in Lisbon area and identify the areas where possible risk to the environment are likely occurring However, it is known that total concentration may not allow a direct prediction of environmental risk, since in general only a fraction of total concentration is available for partitioning between soil and solution and thus to be uptake or transformed by organisms (bioacessible or bioavailable) or to be leached to groundwater. The

  19. Migration chemistry

    International Nuclear Information System (INIS)

    Carlsen, L.

    1992-05-01

    Migration chemistry, the influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour of pollutants in the environment, is an interplay between the actual natur of the pollutant and the characteristics of the environment, such as pH, redox conditions and organic matter content. The wide selection of possible pollutants in combination with varying geological media, as well as the operation of different chemical -, biochemical - and physico-chemical reactions compleactes the prediction of the influence of these processes on the mobility of pollutants. The report summarizes a wide range of potential pollutants in the terrestrial environment as well as a variety of chemical -, biochemical - and physico-chemical reactions, which can be expected to influence the migration behaviour, comprising diffusion, dispersion, convection, sorption/desorption, precipitation/dissolution, transformations/degradations, biochemical reactions and complex formation. The latter comprises the complexation of metal ions as well as non-polar organics to naturally occurring organic macromolecules. The influence of the single types of processes on the migration process is elucidated based on theoretical studies. The influence of chemical -, biochemical - and physico-chemical reactions on the migration behaviour is unambiguous, as the processes apparently control the transport of pollutants in the terrestrial environment. As the simple, conventional K D concept breaks down, it is suggested that the migration process should be described in terms of the alternative concepts chemical dispersion, average-elution-time and effective retention. (AB) (134 refs.)

  20. Risk communication considerations to facilitate the screening of mass populations for potential contamination with radioactive material.

    Science.gov (United States)

    Emery, R J; Sprau, D D; Morecook, R C

    2008-11-01

    Experience gained during a field training exercise with a Medical Reserve Corps unit on the screening of large groups of individuals for possible contamination with radioactive material revealed that while exercise participants were generally attentive to the proper use of protective equipment and detectors, they tended to overlook important basic risk communications aspects. For example, drill participants did not actively communicate with the persons waiting in line for screening, a step which would provide re-assurance, possibly minimize apprehension, and would clarify expectations. When questioned on this issue of risk communication, drill participants were often able to craft ad hoc messages, but the messages were inconsistent and likely would not have significantly helped diminish anxiety and maintain crowd control. Similar difficulties were encountered regarding messaging for persons determined to be contaminated, those departing the screening center, and those to be delivered to the media. Based on these experiences, the need for a suggested list of risk communication points was identified. To address this need, a set of risk communication templates were developed that focused on the issues likely to be encountered in a mass screening event. The points include issues such as the importance of remaining calm, steps for minimizing possible intake or uptake, considerations for those exhibiting acute injuries, expected screening wait times, the process to be followed and the information to be collected, the process to be undertaken for those exhibiting contamination, and symptoms to watch for after departure. Drill participants indicated in follow-up discussions that such pre-established risk communication templates would serve to enhance their ability to assist in times of emergency and noted the potential broader applicably of the approach for use in responses for other disasters types as well.

  1. Toxicological benchmarks for screening potential contaminants of concern for effects on aquatic biota: 1994 Revision

    Energy Technology Data Exchange (ETDEWEB)

    Suter, G.W. II [Oak Ridge National Lab., TN (United States); Mabrey, J.B. [University of West Florida, Pensacola, FL (United States)

    1994-07-01

    This report presents potential screening benchmarks for protection of aquatic life from contaminants in water. Because there is no guidance for screening benchmarks, a set of alternative benchmarks is presented herein. The alternative benchmarks are based on different conceptual approaches to estimating concentrations causing significant effects. For the upper screening benchmark, there are the acute National Ambient Water Quality Criteria (NAWQC) and the Secondary Acute Values (SAV). The SAV concentrations are values estimated with 80% confidence not to exceed the unknown acute NAWQC for those chemicals with no NAWQC. The alternative chronic benchmarks are the chronic NAWQC, the Secondary Chronic Value (SCV), the lowest chronic values for fish and daphnids from chronic toxicity tests, the estimated EC20 for a sensitive species, and the concentration estimated to cause a 20% reduction in the recruit abundance of largemouth bass. It is recommended that ambient chemical concentrations be compared to all of these benchmarks. If NAWQC are exceeded, the chemicals must be contaminants of concern because the NAWQC are applicable or relevant and appropriate requirements (ARARs). If NAWQC are not exceeded, but other benchmarks are, contaminants should be selected on the basis of the number of benchmarks exceeded and the conservatism of the particular benchmark values, as discussed in the text. To the extent that toxicity data are available, this report presents the alternative benchmarks for chemicals that have been detected on the Oak Ridge Reservation. It also presents the data used to calculate benchmarks and the sources of the data. It compares the benchmarks and discusses their relative conservatism and utility.

  2. Aflatoxin contamination of groundnut and maize in Zambia: observed and potential concentrations.

    Science.gov (United States)

    Kachapulula, P W; Akello, J; Bandyopadhyay, R; Cotty, P J

    2017-06-01

    The aims of the study were to quantify aflatoxins, the potent carcinogens associated with stunting and immune suppression, in maize and groundnut across Zambia's three agroecologies and to determine the vulnerability to aflatoxin increases after purchase. Aflatoxin concentrations were determined for 334 maize and groundnut samples from 27 districts using lateral-flow immunochromatography. Seventeen per cent of crops from markets contained aflatoxin concentrations above allowable levels in Zambia (10 μg kg -1 ). Proportions of crops unsafe for human consumption differed significantly (P agroecologies with more contamination (38%) in the warmest (Agroecology I) and the least (8%) in cool, wet Agroecology III. Aflatoxin in groundnut (39 μg kg -1 ) and maize (16 μg kg -1 ) differed (P = 0·032). Poor storage (31°C, 100% RH, 1 week) increased aflatoxin in safe crops by over 1000-fold in both maize and groundnut. The L morphotype of Aspergillus flavus was negatively correlated with postharvest increases in groundnut. Aflatoxins are common in Zambia's food staples with proportions of unsafe crops dependent on agroecology. Fungal community structure influences contamination suggesting Zambia would benefit from biocontrol with atoxigenic A. flavus. Aflatoxin contamination across the three agroecologies of Zambia is detailed and the case for aflatoxin management with atoxigenic biocontrol agents provided. The first method for evaluating the potential for aflatoxin increase after purchase is presented. Published 2017. This article is a U.S. Government work and is in the public domain in the USA. Journal of Applied Microbiology published by John Wiley & Sons Ltd on behalf of The Society for Applied Microbiology.

  3. Hazard identification of contaminated sites. Ranking potential toxicity of organic sediment extracts in crustacean and fish

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, J.; Sundberg, H.; Aakerman, G.; Grunder, K.; Eklund, B.; Breitholtz, M. [Dept. of Applied Environmental Science (ITM), Stockholm Univ. (Sweden)

    2008-09-15

    Background, aim, and scope: It is well known that contaminated sediments represent a potential long-term source of pollutants to the aquatic environment. To protect human and ecosystem health, it is becoming common to remediate contaminated sites. However, the great cost associated with, e.g., dredging in combination with the large numbers of contaminated sites makes it crucial to pinpoint those sites that are in greatest need of remediation. In most European countries, this prioritization process has almost exclusively been based on chemical analyses of known substances; only seldom toxicity data has been considered. The main objective of the current study was therefore to develop a tool for hazard identification of sediment by ranking potential toxicity of organic sediment extracts in a crustacean and a fish. A secondary objective was to investigate the difference in potential toxicity between compounds with different polarities. Materials and methods Early life stages of the crustacean Nitocra spinipes and the fish Oncorhynchus mykiss, which represent organisms from different trophic levels (primary and secondary consumer) and with different routes of exposure (i.e. ingestion through food, diffusive uptake, and maternal transfer), were exposed to hexane and acetone fractions (semi-polar compounds) of sediment from five locations, ranging from heavily to low contaminated. Preliminary tests showed that the extracts were non-bioavailable to the crustacean when exposed via water, and the extracts were therefore loaded on silica gel. Rainbow trout embryos were exposed using nano-injection technique. Results and discussion Clear concentration-response relationships of both mortality and larval development were observed in all tests with N. spinipes. Also for rainbow trout, the observed effects (e.g., abnormality, hemorrhage, asymmetric yolk sac) followed a dose-related pattern. Interestingly, our results indicate that some of the locations contained toxic semi

  4. Contaminant containment using polymer gel barriers

    NARCIS (Netherlands)

    Darwish, M.I.M.; Rowe, R.K.; Maarel, van der J.R.C.; Pel, L.; Huinink, H.P.; Zitha, P.L.J.

    2004-01-01

    Polymer gels are well known in the oil industry, but their potential for use as barriers to contaminant transport has not previously received significant study. As a first step, this paper examines the potential for a polyelectrolyte gel to serve as a barrier to the migration of sodium chloride. Two

  5. Analysis of metal ions migration to determine electro-osmotic flow for the in-situ cleanup of a tar-contaminated site

    KAUST Repository

    Lima, Ana T.

    2012-03-01

    An electro-osmosis experiment was set up on a former asphalt factory site, which is currently contaminated by tar, in Olst, the Netherlands. The main goal of this experiment was to remove polycyclic aromatic hydrocarbons (PAHs) from a contaminated clay layer by applying an electric gradient. But before calculating PAH removal, the direction and intensity of electro-osmosis have to be estimated. In field situations, tracers are used to get information about the water flow. In the present study, the inorganic elements concentration oscillations during electro-osmosis application are used as tracers. The experiment was set up in a clay layer, with the configuration 1m×1m×0.3m, at a depth of 4m below soil surface. Al, Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, S, Si, Ti and Zn concentrations were determined in 28 measurements and were performed during the experimental period of 159days. Then they were used in a first evaluation where auto and cross-correlations were analyzed to aid in the geochemical interpretation and select the most conservative elements. The second part of this study is devoted to estimate the migration of water based on the concentrations development of Cl - at the anode and Na + at the cathode. Electro-osmotic flow was estimated to be intense (2.9 -10 -9-2.18 -10 -8m -s -1) during the first 10 to 50days of experiment and to cease after this period. © 2012.

  6. Analysis of metal ions migration to determine electro-osmotic flow for the in-situ cleanup of a tar-contaminated site

    KAUST Repository

    Lima, Ana T.; Rodrigues, Paulo C.; Loch, J.P. Gustav

    2012-01-01

    An electro-osmosis experiment was set up on a former asphalt factory site, which is currently contaminated by tar, in Olst, the Netherlands. The main goal of this experiment was to remove polycyclic aromatic hydrocarbons (PAHs) from a contaminated clay layer by applying an electric gradient. But before calculating PAH removal, the direction and intensity of electro-osmosis have to be estimated. In field situations, tracers are used to get information about the water flow. In the present study, the inorganic elements concentration oscillations during electro-osmosis application are used as tracers. The experiment was set up in a clay layer, with the configuration 1m×1m×0.3m, at a depth of 4m below soil surface. Al, Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, S, Si, Ti and Zn concentrations were determined in 28 measurements and were performed during the experimental period of 159days. Then they were used in a first evaluation where auto and cross-correlations were analyzed to aid in the geochemical interpretation and select the most conservative elements. The second part of this study is devoted to estimate the migration of water based on the concentrations development of Cl - at the anode and Na + at the cathode. Electro-osmotic flow was estimated to be intense (2.9 -10 -9-2.18 -10 -8m -s -1) during the first 10 to 50days of experiment and to cease after this period. © 2012.

  7. RNA Sequencing of Contaminated Seeds Reveals the State of the Seed Permissive for Pre-Harvest Aflatoxin Contamination and Points to a Potential Susceptibility Factor

    Directory of Open Access Journals (Sweden)

    Josh Clevenger

    2016-11-01

    Full Text Available Pre-harvest aflatoxin contamination (PAC is a major problem facing peanut production worldwide. Produced by the ubiquitous soil fungus, Aspergillus flavus, aflatoxin is the most naturally occurring known carcinogen. The interaction between fungus and host resulting in PAC is complex, and breeding for PAC resistance has been slow. It has been shown that aflatoxin production can be induced by applying drought stress as peanut seeds mature. We have implemented an automated rainout shelter that controls temperature and moisture in the root and peg zone to induce aflatoxin production. Using polymerase chain reaction (PCR and high performance liquid chromatography (HPLC, seeds meeting the following conditions were selected: infected with Aspergillus flavus and contaminated with aflatoxin; and not contaminated with aflatoxin. RNA sequencing analysis revealed groups of genes that describe the transcriptional state of contaminated vs. uncontaminated seed. These data suggest that fatty acid biosynthesis and abscisic acid (ABA signaling are altered in contaminated seeds and point to a potential susceptibility factor, ABR1, as a repressor of ABA signaling that may play a role in permitting PAC.

  8. RNA Sequencing of Contaminated Seeds Reveals the State of the Seed Permissive for Pre-Harvest Aflatoxin Contamination and Points to a Potential Susceptibility Factor

    Science.gov (United States)

    Clevenger, Josh; Marasigan, Kathleen; Liakos, Vasileios; Sobolev, Victor; Vellidis, George; Holbrook, Corley; Ozias-Akins, Peggy

    2016-01-01

    Pre-harvest aflatoxin contamination (PAC) is a major problem facing peanut production worldwide. Produced by the ubiquitous soil fungus, Aspergillus flavus, aflatoxin is the most naturally occurring known carcinogen. The interaction between fungus and host resulting in PAC is complex, and breeding for PAC resistance has been slow. It has been shown that aflatoxin production can be induced by applying drought stress as peanut seeds mature. We have implemented an automated rainout shelter that controls temperature and moisture in the root and peg zone to induce aflatoxin production. Using polymerase chain reaction (PCR) and high performance liquid chromatography (HPLC), seeds meeting the following conditions were selected: infected with Aspergillus flavus and contaminated with aflatoxin; and not contaminated with aflatoxin. RNA sequencing analysis revealed groups of genes that describe the transcriptional state of contaminated vs. uncontaminated seed. These data suggest that fatty acid biosynthesis and abscisic acid (ABA) signaling are altered in contaminated seeds and point to a potential susceptibility factor, ABR1, as a repressor of ABA signaling that may play a role in permitting PAC. PMID:27827875

  9. 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.

  10. RNAi-mediated knockdown of FANCF suppresses cell proliferation, migration, invasion, and drug resistance potential of breast cancer cells

    Directory of Open Access Journals (Sweden)

    L. Zhao

    2014-01-01

    Full Text Available Fanconi anemia complementation group F protein (FANCF is a key factor, which maintains the function of FA/BRCA, a DNA damage response pathway. However, the functional role of FANCF in breast cancer has not been elucidated. We performed a specific FANCF-shRNA knockdown of endogenous FANCF in vitro. Cell viability was measured with a CCK-8 assay. DNA damage was assessed with an alkaline comet assay. Apoptosis, cell cycle, and drug accumulation were measured by flow cytometry. The expression levels of protein were determined by Western blot using specific antibodies. Based on these results, we used cell migration and invasion assays to demonstrate a crucial role for FANCF in those processes. FANCF shRNA effectively inhibited expression of FANCF. We found that proliferation of FANCF knockdown breast cancer cells (MCF-7 and MDA-MB-435S was significantly inhibited, with cell cycle arrest in the S phase, induction of apoptosis, and DNA fragmentation. Inhibition of FANCF also resulted in decreased cell migration and invasion. In addition, FANCF knockdown enhanced sensitivity to doxorubicin in breast cancer cells. These results suggest that FANCF may be a potential target for molecular, therapeutic intervention in breast cancer.

  11. RNAi-mediated knockdown of FANCF suppresses cell proliferation, migration, invasion, and drug resistance potential of breast cancer cells

    International Nuclear Information System (INIS)

    Zhao, L.; Li, N.; Yu, J.K.; Tang, H.T.; Li, Y.L.; He, M.; Yu, Z.J.; Bai, X.F.; Zheng, Z.H.; Wang, E.H.; Wei, M.J.

    2013-01-01

    Fanconi anemia complementation group F protein (FANCF) is a key factor, which maintains the function of FA/BRCA, a DNA damage response pathway. However, the functional role of FANCF in breast cancer has not been elucidated. We performed a specific FANCF-shRNA knockdown of endogenous FANCF in vitro. Cell viability was measured with a CCK-8 assay. DNA damage was assessed with an alkaline comet assay. Apoptosis, cell cycle, and drug accumulation were measured by flow cytometry. The expression levels of protein were determined by Western blot using specific antibodies. Based on these results, we used cell migration and invasion assays to demonstrate a crucial role for FANCF in those processes. FANCF shRNA effectively inhibited expression of FANCF. We found that proliferation of FANCF knockdown breast cancer cells (MCF-7 and MDA-MB-435S) was significantly inhibited, with cell cycle arrest in the S phase, induction of apoptosis, and DNA fragmentation. Inhibition of FANCF also resulted in decreased cell migration and invasion. In addition, FANCF knockdown enhanced sensitivity to doxorubicin in breast cancer cells. These results suggest that FANCF may be a potential target for molecular, therapeutic intervention in breast cancer

  12. RNAi-mediated knockdown of FANCF suppresses cell proliferation, migration, invasion, and drug resistance potential of breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, L.; Li, N.; Yu, J.K.; Tang, H.T.; Li, Y.L.; He, M.; Yu, Z.J.; Bai, X.F. [Department of Pharmacology, School of Pharmacy, China Medical University, Heping Ward, Shenyang City, Liaoning (China); Zheng, Z.H.; Wang, E.H. [Institute of Pathology and Pathophysiology, China Medical University, Heping Ward, Shenyang City, Liaoning (China); Wei, M.J. [Department of Pharmacology, School of Pharmacy, China Medical University, Heping Ward, Shenyang City, Liaoning (China)

    2013-12-12

    Fanconi anemia complementation group F protein (FANCF) is a key factor, which maintains the function of FA/BRCA, a DNA damage response pathway. However, the functional role of FANCF in breast cancer has not been elucidated. We performed a specific FANCF-shRNA knockdown of endogenous FANCF in vitro. Cell viability was measured with a CCK-8 assay. DNA damage was assessed with an alkaline comet assay. Apoptosis, cell cycle, and drug accumulation were measured by flow cytometry. The expression levels of protein were determined by Western blot using specific antibodies. Based on these results, we used cell migration and invasion assays to demonstrate a crucial role for FANCF in those processes. FANCF shRNA effectively inhibited expression of FANCF. We found that proliferation of FANCF knockdown breast cancer cells (MCF-7 and MDA-MB-435S) was significantly inhibited, with cell cycle arrest in the S phase, induction of apoptosis, and DNA fragmentation. Inhibition of FANCF also resulted in decreased cell migration and invasion. In addition, FANCF knockdown enhanced sensitivity to doxorubicin in breast cancer cells. These results suggest that FANCF may be a potential target for molecular, therapeutic intervention in breast cancer.

  13. Heating and thermal control of brazing technique to break contamination path for potential Mars sample return

    Science.gov (United States)

    Bao, Xiaoqi; Badescu, Mircea; Sherrit, Stewart; Bar-Cohen, Yoseph; Campos, Sergio

    2017-04-01

    The potential return of Mars sample material is of great interest to the planetary science community, as it would enable extensive analysis of samples with highly sensitive laboratory instruments. It is important to make sure such a mission concept would not bring any living microbes, which may possibly exist on Mars, back to Earth's environment. In order to ensure the isolation of Mars microbes from Earth's Atmosphere, a brazing sealing and sterilizing technique was proposed to break the Mars-to-Earth contamination path. Effectively, heating the brazing zone in high vacuum space and controlling the sample temperature for integrity are key challenges to the implementation of this technique. The break-thechain procedures for container configurations, which are being considered, were simulated by multi-physics finite element models. Different heating methods including induction and resistive/radiation were evaluated. The temperature profiles of Martian samples in a proposed container structure were predicted. The results show that the sealing and sterilizing process can be controlled such that the samples temperature is maintained below the level that may cause damage, and that the brazing technique is a feasible approach to breaking the contamination path.

  14. Assessing Potential Environmental Contamination by Baylisascaris procyonis Eggs from Infected Raccoons in Southern Texas.

    Science.gov (United States)

    Ogdee, Jacob L; Henke, Scott E; Wester, David B; Fedynich, Alan M

    2017-03-01

    Baylisascaris procyonis is a large ascarid of raccoons (Procyon lotor) and is a zoonotic threat. We documented the potential rate a raccoon population can contaminate their environment with B. procyonis eggs. We estimated the population size of raccoons using a 9 × 7 trapping grid of Havahart traps, identified locations of raccoon scats through systematic searches, and enumerated the distance B. procyonis eggs passively travel from site of origin upon scat decay. During an 8-week capture period, the raccoon population was estimated to be 19.6 ± 1.3 raccoons within the 63-ha study area (1 raccoon/3.2 ha). There were 781 defecation sites, of which 744 (95.3%) were isolated sites and 37 (4.7%) were latrine sites. Fifty-three (6.8%) defecation sites occurred in areas associated with human structures (commensal zone). Of the noncommensal sites, 9 (1.2%) and 719 (98.8%) sites were identified as latrine sites and isolated scats, respectively. More latrine sites were located within the commensal zone (p contaminate 0.03 ± 0.01 ha/year with B. procyonis eggs. Our findings indicate that B. procyonis represents a substantial risk to humans in areas where infected raccoons and humans co-occur.

  15. Engineered Nanoparticles as Potential Food Contaminants and Their Toxicity to Caco-2 Cells.

    Science.gov (United States)

    Mao, Xiaomo; Nguyen, Trang H D; Lin, Mengshi; Mustapha, Azlin

    2016-08-01

    Engineered nanoparticles (ENPs), such as metallic or metallic oxide nanoparticles (NPs), have gained much attention in recent years. Increasing use of ENPs in various areas may lead to the release of ENPs into the environment and cause the contamination of agricultural and food products by ENPs. In this study, we selected two important ENPs (zinc oxide [ZnO] and silver [Ag] NPs) as potential food contaminants and investigated their toxicity via an in vitro model using Caco-2 cells. The physical properties of ENPs and their effects on Caco-2 cells were characterized by electron microscopy and energy dispersive X-ray spectroscopic (EDS) techniques. Results demonstrate that a significant inhibition of cell viability was observed after a 24-h of exposure of Caco-2 cells to 3-, 6-, and 12-mM ZnO NPs or 0.5-, 1.5-, and 3-mM Ag NPs. The noticeable changes of cells include the alteration in cell shape, abnormal nuclear structure, membrane blebbing, and cytoplasmic deterioration. The toxicity of ZnO NPs, but not that of Ag NPs after exposure to simulated gastric fluid, significantly decreased. Scanning transmission electron microscopy shows that ZnO and Ag NPs penetrated the membrane of Caco-2 cells. EDS results also confirm the presence of NPs in the cytoplasm of the cells. This study demonstrates that ZnO and Ag NPs have cytotoxic effects and can inhibit the growth of Caco-2 cells. © 2016 Institute of Food Technologists®

  16. Automated radiological scanning of potentially contaminated railroad crossties for free-release or disposal

    International Nuclear Information System (INIS)

    Hochel, R.C.

    1996-06-01

    The Savannah River Site (SRS) has accumulated approximately 300,000 crossties that have been replaced over a 40-year period of maintaining the site's 62 miles of railroad track. The ties reside in a pile on an open area of 2.3 acres near the site's F-Area facilities. A small fraction of the ties are potentially contaminated with radioactivity as a result of past site practices and service. Contamination was possible from occasional leaks in transport-casks moved by rail from the site's five nuclear materials production reactors to its two reprocessing facilities. Casks typically were filled with spent fuel, targets, and water from the reactor disassembly basins, which contained small amounts of fission and neutron activation product radioactivity normal to the operation of nuclear reactors. What to do with the ties has been debated for sometime. Proposals have ranged from simple burial, to bio-remediation, to burning as a fuel in the site's powerhouse, to free-release to off-site markets. In the past, burial was the disposal method of choice; however, the Department of Energy (DOE) order 5820.2A and premium on new space for low-level waste largely rule out burial. Instead, the last option is now cost effective and was begun under a contract with National Environmental Services Corporation started in January, 1996

  17. Industrially contaminated areas in Serbia as a potential public health threat to the exposed population

    Directory of Open Access Journals (Sweden)

    Matić Branislava I.

    2017-01-01

    Full Text Available Mining and mineral processing is still a vital source of income in Serbia, due to mineral abundance in copper, lead, zinc, antimony. Copper mining and metal-processing are located in the east: Bor, Veliki Krivelj, Cerovo, Majdanpek. Abandoned sites from antimony mining and processing and secondary lead smelter are at the western border: Zajača, Krupanj, Stolice. Coal mining and power plants are surrounding Belgrade: Obrenovac (2 power plants, Grabovac (plant ash landfill, Kolubara and Kostolac. Main objective is to focus on potential public health hazards from industrial contamination in Serbia. Key public health issue is presence of As and Cd in ambient air PM10 close to industrially contaminated sites due to the fact that ores have high naturally occurring contents of heavy metals and metalloids. Data originate from Serbian Environmental Protection Agency, Mining and Metallurgy Institute Bor, Belgrade Institute of Public Health, as part of continuous measurement of air quality within State network of automatic stations. Concentration of As in PM10 are extremely above the limit value in Bor and Lazarevac, with Cd values slightly increased in Bor. Serbia lacks the legal framework for continuous and institutionalized follow-up of population groups vulnerable to hazardous environmental exposure, although measured concentration indicate urgent need for such activities.

  18. Potential of nisin-incorporated sodium caseinate films to control Listeria in artificially contaminated cheese.

    Science.gov (United States)

    Cao-Hoang, Lan; Chaine, Aline; Grégoire, Lydie; Waché, Yves

    2010-10-01

    A sodium caseinate film containing nisin (1000 IU/cm(2)) was produced and used to control Listeria innocua in an artificially contaminated cheese. Mini red Babybel cheese was chosen as a model semi-soft cheese. L. innocua was both surface- and in-depth inoculated to investigate the effectiveness of the antimicrobial film as a function of the distance from the surface in contact with the film. The presence of the active film resulted in a 1.1 log CFU/g reduction in L. innocua counts in surface-inoculated cheese samples after one week of storage at 4 degrees C as compared to control samples. With regard to in-depth inoculated cheese samples, antimicrobial efficiency was found to be dependent on the distance from the surface in contact with the active films to the cheese matrix. The inactivation rates obtained were 1.1, 0.9 and 0.25 log CFU/g for distances from the contact surface of 1 mm, 2 mm and 3 mm, respectively. Our study demonstrates the potential application of sodium caseinate films containing nisin as a promising method to overcome problems associated with post-process contamination, thereby extending the shelf life and possibly enhancing the microbial safety of cheeses. 2010 Elsevier Ltd. All rights reserved.

  19. Solubility and Potential Mobility of Heavy Metals in Two Contaminated Urban Soils from Stockholm, Sweden

    International Nuclear Information System (INIS)

    Oborn, Ingrid; Linde, Mats

    2001-01-01

    The solubility and potential mobility of heavy metals (Cd, Cu,Hg, Pb and Zn) in two urban soils were studied by sequential and leaching extractions (rainwater). Compared to rural (arable) soils on similar parent material, the urban soils were highly contaminated with Hg and Pb and to a lesser extent also with Cd,Cu and Zn. Metal concentrations in rainwater leachates were related to sequential extractions and metal levels reported from Stockholm groundwater. Cadmium and Zn in the soils were mainly recovered in easily extractable fractions, whereas Cu and Pb were complex bound. Concentrations of Pb in the residual fraction were between two- and eightfold those in arable soils, indicating that the sequential extraction scheme did not reflect the solid phases affected by anthropogenic inputs. Cadmium and Zn conc. in the rainwater leachates were within the range detected in Stockholm groundwater, while Cu and Pb conc. were higher, which suggests that Cu and Pb released from the surface soil were immobilised in deeper soil layers. In a soil highly contaminated with Hg, the Hg conc. in the leachate was above the median concentration, but still 50 times lower than the max concentration found in groundwater, indicating the possibility of other sources. In conclusion, it proved difficult to quantitatively predict the mobility of metals in soils by sequential extractions

  20. The potential of Thelypteris palustris and Asparagus sprengeri in phytoremediation of arsenic contamination.

    Science.gov (United States)

    Anderson, LaShunda L; Walsh, Maud; Roy, Amitava; Bianchetti, Christopher M; Merchan, Gregory

    2011-02-01

    The potential of two plants, Thelypteris palustris (marsh fern) and Asparagus sprengeri (asparagus fern), for phytoremediation of arsenic contamination was evaluated. The plants were chosen for this study because of the discovery of the arsenic hyperaccumulating fern, Pteris vittata (Ma et al., 2001) and previous research indicating asparagus fern's ability to tolerate > 1200 ppm soil arsenic. Objectives were (1) to assess if selected plants are arsenic hyperaccumulators; and (2) to assess changes in the species of arsenic upon accumulation in selected plants. Greenhouse hydroponic experiments arsenic treatment levels were established by adding potassium arsenate to solution. All plants were placed into the hydroponic experiments while still potted in their growth media. Marsh fern and Asparagus fern can both accumulate arsenic. Marsh fern bioaccumulation factors (> 10) are in the range of known hyperaccumulator, Pteris vittata Therefore, Thelypteris palustris is may be a good candidate for remediation of arsenic soil contamination levels of arsenic. Total oxidation of As (III) to As (V) does not occur in asparagus fern. The asparagus fern is arsenic tolerant (bioaccumulation factors phytoremediation candidate.

  1. Phytoextraction of potentially toxic elements by Indian mustard, rapeseed, and sunflower from a contaminated riparian soil.

    Science.gov (United States)

    Shaheen, Sabry M; Rinklebe, Jörg

    2015-12-01

    The objective of this study was to quantify the phytoextraction of the potentially toxic elements Al, As, Cd, Co, Cr, Cu, Mo, Ni, Pb, Se, V, and Zn by Indian mustard, rapeseed, and sunflower from a contaminated riparian soil. To achieve this goal, a greenhouse pot experiment was established using a highly contaminated grassland soil collected at the Wupper River (Germany). The impact of ethylene-diamine-tetra-acetic acid (EDTA), humate (HK), and phosphate potassium (PK) on the mobility and uptake of the elements by rapeseed also was investigated. Indian mustard showed the highest efficiency for phytoextraction of Al, Cr, Mo, Se, and V; sunflower for Cd, Ni, Pb, and Zn, and rapeseed for Cu. The bioconcentration ratios were higher than 1 for the elements (except As and Cu), indicating the suitability of the studied plants for phytoextraction. Application of EDTA to the soil increased significantly the solubility of Cd, Co, Cr, Ni, and Pb and decreased the solubility of Al, As, Se, V, and Mo. Humate potassium decreased significantly the concentrations of Al and As in rapeseed but increased the concentrations of Cu, Se, and Zn. We may conclude that HK can be used for immobilization of Al and As, while it can be used for enhancing the phytoextraction of Cu, Se, and Zn by rapeseed. Phosphate potassium immobilized Al, Cd, Pb, and Zn, but enhanced phytoextraction of As, Cr, Mo, and Se by rapeseed.

  2. Meta-analysis of biochar potential for pollutant immobilization and stabilization in contaminated soils

    Science.gov (United States)

    Soja, Gerhard; Marsz, Aleksandra; Fristak, Vladimir

    2015-04-01

    -reviewed literature about the immobilizing potential of biochar for pollutants, we could use about 1300 comparisons of biochar application versus no application for a range of organic and inorganic pollutants in a soil environment. Our assessments have shown that in the average of all studies biochar decreased the availability of cationic heavy metals and organic pollutants significantly by 40-50 %. We could confirm that an increasing biochar application rate also increases contaminant sorption. The only exception was found for anionic heavy metals like As or Mo that are clearly mobilized by biochar applications. Differences in sorption efficiency depend on the type of biochar, on different pollutants and on the compartment where the reduction of bioavailability has been studied.

  3. Potential Application of Nanomaterials to treat and detect the contaminated water

    Science.gov (United States)

    Singh, R. P.

    2011-12-01

    An ecosystem is very immense to maintain global environmental balance but an imbalance of water alters the function of ecosystems that affects all life on our planet Earth. The destruction of agricultural land, lakes, ponds, rivers, and oceans locally and globally creates environmental imbalances so that catastrophically damage to be appeared widely. The water cycle continually circulates evaporated water into the atmosphere and returns it as precipitation in balance form. If variety of toxins, heavy metals, oils and agricultural chemicals such as pesticides and fertilizers, all get absorbed into soil and groundwater. Then an imbalance appeared for example runoff carries these pollutants into lakes, rivers and oceanic water, as a result, all forms of water evaporated as part of the water cycle and return to the earth as acid rain, which causes worldwide environmental imbalances by killing our ecosystems. Deforestation, urbanization, and industrialization create environmental imbalances in many ways. Soil erosion in the form of dust from wind causes human infectious diseases, including anthrax and tuberculosis. An environmental imbalance occurs due to greenhouse gases, which accumulate in the atmosphere and trap excessive amounts of heat causes global warming, that is purportedly responsible for environmental disasters such as, rising sea levels, floods and the melting of polar ice caps. Our problem is "all talk, no action" and "jack of all trades, master of none". Our efforts in this hot topic are to make balance of water rather than imbalance of water by using positive potential of naomaterials utility and applications to eliminate toxicants/pollutants/adulterants/carcinogens from all forms of imbalance water to save our local and global ecosystems as a balance and healthy wealthy. Several natural, engineered, and non-engineered nanomaterials have strong antimicrobial properties (e.g. TiO2, ZnO, AgNPs, CNTs, fullerene, graphene), used as antimicrobial agents as

  4. Potential and real ecological threat of heavy metals in contaminated soils

    Science.gov (United States)

    Motuzova, Galina; Barsova, Natalia; Makarichev, Ivan; Karpova, Elena

    2013-04-01

    Introduction. Microelements or heavy metals (HM) occur in nature and are required for living organisms at low concentrations. High content of HM in soils characterize their potential danger for ecosystem. Their real ecological threat is presented by the mobility of HM in soils. The aim of this work was to characterize the potential and real danger of HM on the basis of HM mobility in soils and their influence of the most important soils properties. Materials and methods. Two types of materials are presented in this paper. The first ones are presented by the summarized information about the content of Cu, Zn, Mn and their mobile species in the soils of Russia and are included into the National Atlas of Russian soils (2011). The second part is presented by the results of laboratory experiments with some samples of Podzols, Podzoluvisol and Chernozem. The following parameters have been determined: a) the main chemical properties of soils; b) the water extracts from soils were investigated by the potentiometric titration with HM salts; c) the properties of the samples of humic acids (HA, extracted by 1n. NaOH) and HA-Cu complexes were determined: molecular-masses distribution (MMD), infrared spectra (IRS), hydrophobility, 1? NMR spectra Results and discussions. The major part of HM in soils of natural landscapes is firmly bound to several minerals. Their threat for living organisms is largely dependent on a relatively higher mobility of HM in soils. The main factors affecting the mobility of HM include soil reaction and sorption processes. In soils of natural landscapes the share of mobile HM compounds is estimated as some per cents from their total content. Having used the data about microelements in soils, their availability to living organisms, 14 natural biogeochemical provinces have been distinguished at the territory of the European part of the former USSR. It permitted to show the adverse impact rendered by microelements at low or high concentrations on living

  5. Phytoremediation potential of Eichornia crassipes in metal-contaminated coastal water.

    Science.gov (United States)

    Agunbiade, Foluso O; Olu-Owolabi, Bamidele I; Adebowale, Kayode O

    2009-10-01

    The potential of Eichornia crassipes to serve as a phytoremediation plant in the cleaning up of metals from contaminated coastal areas was evaluated in this study. Ten metals, As, Cd, Cu, Cr, Fe, Mn, Ni, Pb, V and Zn were assessed in water and the plant roots and shoots from the coastal area of Ondo State, Nigeria and the values were used to evaluate the enrichment factor (EF) and translocation factor (TF) in the plant. The critical concentrations of the metals were lower than those specified for hyperaccumulators thus classifying the plant as an accumulator but the EF and TF revealed that the plant accumulated toxic metals such as Cr, Cd, Pb and As both at the root and at the shoot in high degree, which indicates that the plant that forms a large biomass on the water surface and is not fed upon by animals can serve as a plant for both phytoextraction and rhizofiltration in phytoremediation technology.

  6. Impact of Saw Dust Application on the Distribution of Potentially Toxic Metals in Contaminated Soil.

    Science.gov (United States)

    Awokunmi, Emmmanuel E

    2017-12-01

    The need to develop an approach for the reclamation of contaminated site using locally available agricultural waste has been considered. The present study investigated the application of sawdust as an effective amendment in the immobilization of potentially toxic metals (PTMs) by conducting a greenhouse experiment on soil collected from an automobile dumpsite. The amended and non-amended soil samples were analyzed for their physicochemical parameters and sequential extraction of PTMs. The results revealed that application of amendment had positive impact on the physicochemical parameters as organic matter content and cation exchange capacity increased from 12.1% to 12.8% and 16.4 to 16.8 meq/100 g respectively. However, the mobility and bioavalability of these metals was reduced as they were found to be distributed mostly in the non-exchangeable phase of soil. Therefore, application of sawdust successfully immobilized PTMs and could be applied for future studies in agricultural soil reclamation.

  7. Assessment of the potential radiological impact of residual contamination in the Maralinga and Emu areas

    International Nuclear Information System (INIS)

    Haywood, S.M.; Smith, J.

    1990-10-01

    The report presents an assessment of potential doses to future inhabitants of the Maralinga and Emu areas of Southern Australia, where nuclear weapons tests in the 1950s and 1960s resulted in widespread residual radioactive contamination. Annual effective doses of several millisieverts would be expected to result from continual occupancy within contours enclosing areas of several hundred square kilometres. Larger predicted annual effective doses - of the order of 0.5 Sv -would be expected to occur from 100% occupancy in small regions immediately surrounding the test sites, but continual occupancy of such areas is highly unlikely because of their small size. The most significant dose pathways are inhalation of resuspended activity and ingestion of soil by infants. An analysis of the effects of uncertainties in the dose calculation indicated the uncertainty distribution on predicted doses from the inhalation pathway. (author)

  8. Outlier identification in urban soils and its implications for identification of potential contaminated land

    Science.gov (United States)

    Zhang, Chaosheng

    2010-05-01

    Outliers in urban soil geochemical databases may imply potential contaminated land. Different methodologies which can be easily implemented for the identification of global and spatial outliers were applied for Pb concentrations in urban soils of Galway City in Ireland. Due to its strongly skewed probability feature, a Box-Cox transformation was performed prior to further analyses. The graphic methods of histogram and box-and-whisker plot were effective in identification of global outliers at the original scale of the dataset. Spatial outliers could be identified by a local indicator of spatial association of local Moran's I, cross-validation of kriging, and a geographically weighted regression. The spatial locations of outliers were visualised using a geographical information system. Different methods showed generally consistent results, but differences existed. It is suggested that outliers identified by statistical methods should be confirmed and justified using scientific knowledge before they are properly dealt with.

  9. 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.

  10. Pesticide and Water management alternatives to mitigate potential ground-water contamination for selected counties in Utah

    OpenAIRE

    Ehteshami, Majid; Requena, Antonio M.; Peralta, R. C.; Deer, Howard M.; Hill, Robert W.; Ranjha, Ahmad Yar

    1990-01-01

    Production of adequate supplies of food and fiber currently requires that pesticides be used to limit crop losses from insects, pathogens, weeds and other pests. Although pesticides are necessary in today's agriculture, they can be a serious problem if they reach and contaminate ground water, especially in places where drinking water needs are supplied from ground water. The relative reduction of potential ground-water contamination due to agricultural use of pesticides was analyzed for parti...

  11. Monitoring underground migration of sequestered CO2 using self-potential methods

    Science.gov (United States)

    Ishido, T.; Pritchett, J.; Tosha, T.; Nishi, Y.; Nakanishi, S.

    2013-12-01

    An appropriate monitoring program is indispensable for an individual geologic storage project to aid in answering various operational questions by detecting changes within the reservoir and to provide early warning of potential CO2 leakage through the caprock. Such a program is also essential to reduce uncertainties associated with reservoir parameters and to improve the predictive capability of reservoir models. Repeat geophysical measurements performed at the earth surface show particular promise for monitoring large subsurface volumes. To appraise the utility of geophysical techniques, Ishido et al. carried out numerical simulations of an aquifer system underlying a portion of Tokyo Bay and calculated the temporal changes in geophysical observables caused by changing underground conditions as computed by reservoir simulation (Energy Procedia, 2011). They used 'geophysical postprocessors' to calculate the resulting temporal changes in the earth-surface distributions of microgravity, self-potential (SP), apparent resistivity (from MT surveys) and seismic observables. The applicability of any particular method is likely to be highly site-specific, but these calculations indicate that none of these techniques should be ruled out altogether. Some survey techniques (gravity, MT resistivity) appear to be suitable for characterizing long-term changes, whereas others (seismic reflection, SP) are quite responsive to short term disturbances. The self-potential postprocessor calculates changes in subsurface electrical potential induced by pressure disturbances through electrokinetic coupling (Ishido & Pritchett, JGR 1999). In addition to electrokinetic coupling, SP anomalies may be generated by various other mechanisms such as thermoelectric coupling, electrochemical diffusion potential, etc. In particular, SP anomalies of negative polarity, which are frequently observed near wells, appear to be caused by an underground electrochemical mechanism similar to a galvanic cell

  12. Migration and differentiation potential of stem cells in the cnidarian Hydractinia analysed in eGFP-transgenic animals and chimeras.

    Science.gov (United States)

    Künzel, Timo; Heiermann, Reinhard; Frank, Uri; Müller, Werner; Tilmann, Wido; Bause, Markus; Nonn, Anja; Helling, Matthias; Schwarz, Ryan S; Plickert, Günter

    2010-12-01

    To analyse cell migration and the differentiation potential of migratory stem cells in Hydractinia, we generated animals with an eGFP reporter gene stably expressed and transmitted via the germline. The transgene was placed under the control of two different actin promoters and the promoter of elongation factor-1α. One actin promoter (Act-II) and the EF-1α promoter enabled expression of the transgene in all cells, the other actin promoter (Act-I) in epithelial and gametogenic cells, but not in the pluripotent migratory stem cells. We produced chimeric animals consisting of histocompatible wild type and transgenic parts. When the transgene was under the control of the epithelial cell specific actin-I promoter, non-fluorescent transgenic stem cells immigrated into wild type tissue, stopped migration and differentiated into epithelial cells which then commenced eGFP-expression. Migratory stem cells are therefore pluripotent and can give rise not only to germ cells, nematocytes and nerve cells, but also to epithelial cells. While in somatic cells expression of the act-I promoter was restricted to epithelial cells it became also active in gametogenesis. The act-I gene is expressed in spermatogonia, oogonia and oocytes. In males the expression pattern showed that migratory stem cells are the precursors of both the spermatogonia and their somatic envelopes. Comparative expression studies using the promoters of the actin-II gene and the elongation factor-1α gene revealed the potential of transgenic techniques to trace the development of the nervous system. Copyright © 2010 Elsevier Inc. All rights reserved.

  13. A Comprehensive and Systematic Approach to Developing and Documenting Conceptual Models of Contaminant Release and Migration at the Hanford Site

    International Nuclear Information System (INIS)

    Last, George V.; Rohay, Virginia J.; Schelling, F J.; Bunn, Amoret L.; Delamare, Michael A.; Dirkes, Roger L.; Hildebrand, R D.; Morse, John G.; Napier, Bruce A.; Riley, Robert G.; Soler, Luis; Thorne, Paul D.

    2004-01-01

    The U. S. Department of Energy?s Richland Operations Office has initiated efforts to adapt and implement the Features, Events, and Processes (FEPs) methodology (used in scenario development for nuclear waste disposal programs) to the environmental management and remediation problems facing the Hanford Site. These efforts have shown that modification of the FEPs methodology to incorporate the use of Process Relationship Diagrams (PRD) is effective in facilitating the development of conceptual models and selection of potentially relevant factors to be incorporated into a specific performance assessment. In developing this methodology for Hanford, a master PRD was created to provide an organization structure for identifying the potentially relevant factors (i.e. FEPs) and for illustrating the relationships between these factors. This organizational framework was developed to match the organization of current Hanford site-wide performance assessment activities and to facilitate screening of the FEPs relevant to the problems (and conceptual models) that need to be addressed at the site. However, the link between Hanford specific FEPs and the international list of FEPs was maintained to demonstrate completeness and perhaps to expand the usefulness of the international list for other environmental programs

  14. Hydrology/Radionuclide Migration Program and related research activities

    International Nuclear Information System (INIS)

    Jones, M.A.

    1992-02-01

    This report presents the results of technical studies conducted under the Hydrology/Radionuclide Migration Program (HRMP) at the Nevada Test Site (NTS) for the period of October 1, 1985 through September 30, 1986. The HRMP was initiated in 1973 as the Radionuclide Migration Program to study and better understand the hydrologic systems of the NTS and potential movement and rates of movement of radionuclides and other contaminants injected into these systems by underground nuclear testing

  15. Estimation of Potential Population Level Effects of Contaminants on Wildlife; FINAL

    International Nuclear Information System (INIS)

    Loar, J.M.

    2001-01-01

    The objective of this project is to provide DOE with improved methods to assess risks from contaminants to wildlife populations. The current approach for wildlife risk assessment consists of comparison of contaminant exposure estimates for individual animals to literature-derived toxicity test endpoints. These test endpoints are assumed to estimate thresholds for population-level effects. Moreover, species sensitivities to contaminants is one of several criteria to be considered when selecting assessment endpoints (EPA 1997 and 1998), yet data on the sensitivities of many birds and mammals are lacking. The uncertainties associated with this approach are considerable. First, because toxicity data are not available for most potential wildlife endpoint species, extrapolation of toxicity data from test species to the species of interest is required. There is no consensus on the most appropriate extrapolation method. Second, toxicity data are represented as statistical measures (e.g., NOAEL s or LOAELs) that provide no information on the nature or magnitude of effects. The level of effect is an artifact of the replication and dosing regime employed, and does not indicate how effects might increase with increasing exposure. Consequently, slight exceedance of a LOAEL is not distinguished from greatly exceeding it. Third, the relationship of toxic effects on individuals to effects on populations is poorly estimated by existing methods. It is assumed that if the exposure of individuals exceeds levels associated with impaired reproduction, then population level effects are likely. Uncertainty associated with this assumption is large because depending on the reproductive strategy of a given species, comparable levels of reproductive impairment may result in dramatically different population-level responses. This project included several tasks to address these problems: (1) investigation of the validity of the current allometric scaling approach for interspecies extrapolation

  16. Subsurface contaminants focus area

    International Nuclear Information System (INIS)

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites

  17. Subsurface contaminants focus area

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  18. Inventory of drainage wells and potential sources of contaminants to drainage-well inflow in Southwest Orlando, Orange County, Florida

    Science.gov (United States)

    Taylor, George Fred

    1993-01-01

    Potential sources of contaminants that could pose a threat to drainage-well inflow and to water in the Floridan aquifer system in southwest Orlando, Florida, were studied between October and December 1990. Drainage wells and public-supply wells were inventoried in a 14-square-mile area, and available data on land use and activities within each drainage well basin were tabulated. Three public-supply wells (tapping the Lower Floridan aquifer) and 38 drainage wells (open to the Upper Floridan aquifer) were located in 17 drainage basins within the study area. The primary sources of drainage-well inflow are lake overflow, street runoff, seepage from the surficial aquifer system, and process-wastewater disposal. Drainage-well inflow from a variety of ares, including resi- dential, commercial, undeveloped, paved, and industrial areas, are potential sources of con- taminants. The four general types of possible contaminants to drainage-well inflow are inorganic chemicals, organic compounds, turbidity, and microbiological contaminants. Potential contami- nant sources include plant nurseries, citrus groves, parking lots, plating companies, auto- motive repair shops, and most commonly, lake- overflow water. Drainage wells provide a pathway for contaminants to enter the Upper Floridan aquifer and there is a potential for contaminants to move downward from the Upper Floridan to the Lower Floridan aquifer.

  19. Ionizing radiation in the disinfection of water contaminated with potentially pathogenic mycobacteria

    International Nuclear Information System (INIS)

    Kubin, M.; Sedlackova, J.; Vacek, K.

    1982-01-01

    Sterile drinking water samples were artificially colonized with M. kansasii, M. gardonae and M. fortuitum suspensions (the numbers of viable units in 1 ml were 1.2x10 3 , 48.5 and 3.2x10 3 , respectively) prepared from mycobacterial strains replicated in Tween 80-free liquid Dubos medium STO. The contaminated water samples were irradiated from a rotary cobalt 60 source (gamma radiation, E=1.17 and 1.33 MeV, dose rate 1 kJ/kg.h at room temperature) with doses 0.7, 1.5, 2.2, 3, 9, 16 and 27 kJ/kg. The disinfecting effectiveness was assessed by direct cultivation tests (0.5 ml volumes of water inoculated on egg medium) and by cultivation on membrane filtres after filtering the whole amount of the water examined (about 500 ml). Total disinfection was recorded for M. kansasii and M. fortuitum irradiated with 9 kJ/kg and for M. gordonae after irradiation with 1.5 kJ/kg. The calculated value of D 10 =0.4 kJ/kg (i.e., the radiation dose that reduces the number of viable mycobacteria by an order of magnitude) is suggestive of a strong disinfecting effect of ionizing radiation on the tested strains of potentially pathogenic mycobacteria. The results indicate that ionizing radiation could be applxcable in disinfecting supply and potable water contaminated with mycobacteria difficult to remove by other methods which, as a rule, cannot ensure permanent disinfection. (author)

  20. Ionizing radiation in the disinfection of water contaminated with potentially pathogenic mycobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Kubin, M [Institut Hygieny a Epidemiologie, Prague (Czechoslovakia); Sedlackova, J; Vacek, K [Ustav Jaderneho Vyzkumu CSKAE, Rez (Czechoslovakia)

    1982-01-01

    Sterile drinking water samples were artificially colonized with M. kansasii, M. gardonae and M. fortuitum suspensions (the numbers of viable units in 1 ml were 1.2x10/sup 3/, 48.5 and 3.2x10/sup 3/, respectively) prepared from mycobacterial strains replicated in Tween 80-free liquid Dubos medium STO. The contaminated water samples were irradiated from a rotary cobalt 60 source (gamma radiation, E=1.17 and 1.33 MeV, dose rate 1 kJ/kg.h at room temperature) with doses 0.7, 1.5, 2.2, 3, 9, 16 and 27 kJ/kg. The disinfecting effectiveness was assessed by direct cultivation tests (0.5 ml volumes of water inoculated on egg medium) and by cultivation on membrane filtres after filtering the whole amount of the water examined (about 500 ml). Total disinfection was recorded for M. kansasii and M. fortuitum irradiated with 9 kJ/kg and for M. gordonae after irradiation with 1.5 kJ/kg. The calculated value of D/sub 10/=0.4 kJ/kg (i.e., the radiation dose that reduces the number of viable mycobacteria by an order of magnitude) is suggestive of a strong disinfecting effect of ionizing radiation on the tested strains of potentially pathogenic mycobacteria. The results indicate that ionizing radiation could be applicable in disinfecting supply and potable water contaminated with mycobacteria difficult to remove by other methods which, as a rule, cannot ensure permanent disinfection.

  1. Perched aquifers - their potential impact on contaminant transport in the southern High Plains, Texas

    International Nuclear Information System (INIS)

    Mullican, W.F. III; Fryar, A.E.; Johns, N.D.

    1993-01-01

    Understanding the hydrogeology and hydrochemistry of perched aquifers at potential and known contaminated waste sites has become increasingly important because of the impact these aquifers may have on contaminant transport independent of regional aquifer processes. Investigations of a perched aquifer above the Ogallala aquifer are being conducted in the region of the U.S. Department of Energy's Pantex Plant, a proposed Superfund site, located approximately 20 mi northeast of Amarillo, Texas. Since the early 1950s, a small playa basin located on the Pantex Plant has been used as a waste-water discharge pond with daily discharge rates ranging from 400,000 to 1 million gal. The focus of this investigation is an unconfined, perched aquifer that overlies a thick silty clay sequence within the upper, mostly unsaturated part of the Ogallala Formation (Neogene). In the area of the Pantex Plant, measured depths to the perched aquifer range from 200 to 300 ft below land surface, whereas depth to the regional Ogallala aquifer ranges from 375 to 500 ft. The potentiometric surface of the perched aquifer typically represents groundwater mounds proximal to the playas and thins into trough in the interplaya areas. Hydrologic gradients of the primary mound under investigation are relatively high, ranging from 28 to 45 ft/mi. Calculated transmissivities have a geometric mean of 54 ft 2 /day, with saturated thicknesses ranging from 4 to 1000 ft. Modeling of the perched aquifer was designed to determine how much, if any, discharge to the small playa basin has enhanced recharge to the perched aquifers and increased the vertical and lateral extent of the perched aquifer. Preliminary results indicate that measurements of vertical conductance through the perching silty-clay sequence and recharge rates through playas are critical for calibrating the model. Accurate delineation of rates and flow directions in the perched aquifer is critical to any successful remediation effort

  2. Stray dogs and cats as potential sources of soil contamination with zoonotic parasites.

    Science.gov (United States)

    Szwabe, Katarzyna; Blaszkowska, Joanna

    2017-03-22

    The main source of many zoonoses is soil contaminated with feline and canine faeces. Thus, the aim of this study was to estimate the prevalence of intestinal parasites in stray dogs and cats adopted in Lodz shelter (Poland). In total, 163 faecal samples were collected from 95 dogs and 68 cats from 2011 to 2012. The samples were processed by sedimentation techniques using Mini Parasep®SF. Six parasite genera belonging to protozoa, cestoda, and nematoda, were found in dogs, while eight were found in cats. Out of the 163 fecal samples, 37.4% were positive for the presence at least one species of intestinal parasites. The majority of positive dog samples contained eggs from Toxocara and Trichuris genera, and the family Ancylostomatidae, while Toxocara and Taenia eggs, as well as Cystoisospora oocysts, predominated in cat faeces. A significantly higher prevalence of parasites was noted in cats (48.5%) than in dogs (29.5%) (χ2=6.15, P=0.013). The Toxocara genus was the most prevalent parasite in both populations; eggs were found in 27.9% and 16.8% of cats and dogs, respectively. Animals younger than 12 months of age showed higher infection rates with Toxocara, but differences were not statistically significant. The average numbers of Toxocara eggs/gram of faeces in positive puppy and kitten samples were over 5 and 7 times higher than in older dogs and cats, respectively. Mixed infection were found in dogs (5.3%) and cats (8.8%). Cat faeces represent a more important potential source of environmental contamination with zoonotic parasites than dog faeces. Among the detected parasites of stray dogs and cats, Toxocara present an important zoonotic risk for the local human population, especially children.

  3. Analysis of potential groundwater contamination in the vicinity of the Weldon Spring Raffinate Pits site, Weldon Spring, Missouri

    International Nuclear Information System (INIS)

    Tsai, S.Y.; Peterson, J.M.; Winters, M.C.B.

    1984-08-01

    Results of the analysis of contaminant migration beneath the raffinate pits at the Weldon Spring Raffinate Pits site indicate that during a 10,000-year time period, the maximum concentrations in the water immediately beneath the pit bottoms would be about 4600 pCi/L of radium-226 (Pit 3) and about 12,000 pCi/L of uranium-238 (Pit 1); these concentrations would occur at the centers of the pit bottoms. Based on the assumptions used in this study, the radioactive contaminants in the pits would migrate no more than 2 m (7 ft) below the pit bottoms. Because 6 to 12 m (20 to 40 ft) of silty clays underlie the raffinate pits, the radioactive contaminants would take several tens of thousands of years to reach nearby groundwater supplies. Although the results of these analyses indicate that a high degree of confinement is provided by the four raffinate pits, it should be noted that the validity of such analyses rests on the quality of the parameter values utilized. Due to a lack of current site-specific data for some physical parameters, it has been necessary to use historical and regional data for these values. The values cited are at times inconsistent and contradictory, e.g., the wide range of values indicated for the permeability of clays underlying the pits. However, these were the only data available. The analysis reported herein indicates that within the limitations of the available data, use of the Raffinate Pits site for long-term management of radioactive materials such as those currently being stored in the four pits appears to be feasible. 24 references, 14 figures, 7 tables

  4. Impact of Potentially Contaminated River Water on Agricultural Irrigated Soils in an Equatorial Climate

    Directory of Open Access Journals (Sweden)

    Juan M. Trujillo-González

    2017-06-01

    Full Text Available Globally, it is estimated that 20 million hectares of arable land are irrigated with water that contains residual contributions from domestic liquids. This potentially poses risks to public health and ecosystems, especially due to heavy metals, which are considered dangerous because of their potential toxicity and persistence in the environment. The Villavicencio region (Colombia is an equatorial area where rainfall (near 3000 mm/year and temperature (average 25.6 °C are high. Soil processes in tropical conditions are fast and react quickly to changing conditions. Soil properties from agricultural fields irrigated with river water polluted by a variety of sources were analysed and compared to non-irrigated control soils. In this study, no physico-chemical alterations were found that gave evidence of a change due to the constant use of river water that contained wastes. This fact may be associated with the climatic factors (temperature and precipitation, which contribute to fast degradation of organic matter and nutrient and contaminants (such as heavy metals leaching, or to dilution of wastes by the river.

  5. Cadmium contamination in orchard soils and fruit trees and its potential health risk in Guangzhou, China.

    Science.gov (United States)

    Li, J T; Qiu, J W; Wang, X W; Zhong, Y; Lan, C Y; Shu, W S

    2006-09-01

    This study examines cadmium (Cd) contamination in orchard soils and fruit trees in Guangzhou, China, and assesses its potential health risk. Soils and tissues samples of three species of fruit trees were collected from three orchards. The average soil Cd concentration was 1.27, 1.84 and 0.68 mg/kg in orchards I, II, and III, respectively. The carambola (Averrhoa carambola) accumulated exceptionally high concentrations of Cd (7.57, 10.84, 9.01 and 2.15 mg/kg dw in root, twig, leaf and fruit, respectively), being 6.0-24 times and 4.0-10 times the corresponding tissue Cd in the longan (Dimocarpus longan) and wampee (Clausena lansium), respectively. Furthermore, all Cd concentrations (0.04-0.25 mg Cd/kg fw) of the fruits exceeded the tolerance limit of cadmium in foods of PR China (0.03 mg/kg fw). Our results indicate that the carambola tree has high Cd accumulation capacity and might be a Cd accumulator; and its fruit, among the three species of fruits studied, also poses the highest potential health risk to local residents.

  6. Cadmium contamination in orchard soils and fruit trees and its potential health risk in Guangzhou, China

    Energy Technology Data Exchange (ETDEWEB)

    Li, J.T. [School of Life Sciences and State Key Laboratory of Biocontrol, Sun Yat-sen (Zhongshan) University, Guangzhou 510275 (China); Qiu, J.W. [Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong (China); Wang, X.W. [School of Life Sciences and State Key Laboratory of Biocontrol, Sun Yat-sen (Zhongshan) University, Guangzhou 510275 (China); Zhong, Y. [School of Life Sciences and State Key Laboratory of Biocontrol, Sun Yat-sen (Zhongshan) University, Guangzhou 510275 (China); Lan, C.Y. [School of Life Sciences and State Key Laboratory of Biocontrol, Sun Yat-sen (Zhongshan) University, Guangzhou 510275 (China)]. E-mail: ls04@zsu.edu.cn; Shu, W.S. [School of Life Sciences and State Key Laboratory of Biocontrol, Sun Yat-sen (Zhongshan) University, Guangzhou 510275 (China)]. E-mail: ls53@zsu.edu.cn

    2006-09-15

    This study examines cadmium (Cd) contamination in orchard soils and fruit trees in Guangzhou, China, and assesses its potential health risk. Soils and tissues samples of three species of fruit trees were collected from three orchards. The average soil Cd concentration was 1.27, 1.84 and 0.68 mg/kg in orchards I, II, and III, respectively. The carambola (Averrhoa carambola) accumulated exceptionally high concentrations of Cd (7.57, 10.84, 9.01 and 2.15 mg/kg dw in root, twig, leaf and fruit, respectively), being 6.0-24 times and 4.0-10 times the corresponding tissue Cd in the longan (Dimocarpus longan) and wampee (Clausena lansium), respectively. Furthermore, all Cd concentrations (0.04-0.25 mg Cd/kg fw) of the fruits exceeded the tolerance limit of cadmium in foods of PR China (0.03 mg/kg fw). Our results indicate that the carambola tree has high Cd accumulation capacity and might be a Cd accumulator; and its fruit, among the three species of fruits studied, also poses the highest potential health risk to local residents. - Carambola fruit can accumulate high levels of cadmium and may be a health risk for humans.

  7. Cadmium contamination in orchard soils and fruit trees and its potential health risk in Guangzhou, China

    International Nuclear Information System (INIS)

    Li, J.T.; Qiu, J.W.; Wang, X.W.; Zhong, Y.; Lan, C.Y.; Shu, W.S.

    2006-01-01

    This study examines cadmium (Cd) contamination in orchard soils and fruit trees in Guangzhou, China, and assesses its potential health risk. Soils and tissues samples of three species of fruit trees were collected from three orchards. The average soil Cd concentration was 1.27, 1.84 and 0.68 mg/kg in orchards I, II, and III, respectively. The carambola (Averrhoa carambola) accumulated exceptionally high concentrations of Cd (7.57, 10.84, 9.01 and 2.15 mg/kg dw in root, twig, leaf and fruit, respectively), being 6.0-24 times and 4.0-10 times the corresponding tissue Cd in the longan (Dimocarpus longan) and wampee (Clausena lansium), respectively. Furthermore, all Cd concentrations (0.04-0.25 mg Cd/kg fw) of the fruits exceeded the tolerance limit of cadmium in foods of PR China (0.03 mg/kg fw). Our results indicate that the carambola tree has high Cd accumulation capacity and might be a Cd accumulator; and its fruit, among the three species of fruits studied, also poses the highest potential health risk to local residents. - Carambola fruit can accumulate high levels of cadmium and may be a health risk for humans

  8. The potential for health risks from intrusion of contaminants into the distribution system from pressure transients.

    Science.gov (United States)

    LeChevallier, Mark W; Gullick, Richard W; Karim, Mohammad R; Friedman, Melinda; Funk, James E

    2003-03-01

    The potential for public health risks associated with intrusion of contaminants into water supply distribution systems resulting from transient low or negative pressures is assessed. It is shown that transient pressure events occur in distribution systems; that during these negative pressure events pipeline leaks provide a potential portal for entry of groundwater into treated drinking water; and that faecal indicators and culturable human viruses are present in the soil and water exterior to the distribution system. To date, all observed negative pressure events have been related to power outages or other pump shutdowns. Although there are insufficient data to indicate whether pressure transients are a substantial source of risk to water quality in the distribution system, mitigation techniques can be implemented, principally the maintenance of an effective disinfectant residual throughout the distribution system, leak control, redesign of air relief venting, and more rigorous application of existing engineering standards. Use of high-speed pressure data loggers and surge modelling may have some merit, but more research is needed.

  9. The potential of genetic engineering of plants for the remediation of soils contaminated with heavy metals.

    Science.gov (United States)

    Fasani, Elisa; Manara, Anna; Martini, Flavio; Furini, Antonella; DalCorso, Giovanni

    2018-05-01

    The genetic engineering of plants to facilitate the reclamation of soils and waters contaminated with inorganic pollutants is a relatively new and evolving field, benefiting from the heterologous expression of genes that increase the capacity of plants to mobilize, stabilize and/or accumulate metals. The efficiency of phytoremediation relies on the mechanisms underlying metal accumulation and tolerance, such as metal uptake, translocation and detoxification. The transfer of genes involved in any of these processes into fast-growing, high-biomass crops may improve their reclamation potential. The successful phytoextraction of metals/metalloids and their accumulation in aerial organs have been achieved by expressing metal ligands or transporters, enzymes involved in sulfur metabolism, enzymes that alter the chemical form or redox state of metals/metalloids and even the components of primary metabolism. This review article considers the potential of genetic engineering as a strategy to improve the phytoremediation capacity of plants in the context of heavy metals and metalloids, using recent case studies to demonstrate the practical application of this approach in the field. © 2017 John Wiley & Sons Ltd.

  10. Bioremediation a potential approach for soil contaminated with polycyclic aromatic hydrocarbons: An Overview

    OpenAIRE

    Norzila Othman; Mohd Irwan Juki; Norhana Hussain; Suhaimi Abdul Talib

    2011-01-01

    Polycyclic aromatic hydrocarbons (PAHs) represent a group of priority pollutants which are present at high concentration in soils of many industrially contaminated sites. Standards and criteria for the remediation of soils contaminated with PAHs vary widely between countries. Bioremediation has gained preference as a technology for remediation contaminated sites as it is less expensive and more environmental friendly. Bioremediation utilizes microorganisms to degrade PAHs to less toxic compou...

  11. Monitoring Potential Transport of Radioactive Contaminants in Shallow Ephemeral Channels: FY2017

    Energy Technology Data Exchange (ETDEWEB)

    Mizell, Steve A. [Desert Research Inst. (DRI), Las Vegas, NV (United States); Campbell, Scott A. [Desert Research Inst. (DRI), Las Vegas, NV (United States); McCurdy, Greg [Desert Research Inst. (DRI), Las Vegas, NV (United States); Miller, Julianne J. [Desert Research Inst. (DRI), Las Vegas, NV (United States)

    2018-04-01

    The Desert Research Institute (DRI) is conducting a field assessment of the potential for contaminated soil to be transported from the Smoky Site Contamination Area (CA) as a result of storm runoff. This activity supports U.S. Department of Energy (DOE) Environmental Management Nevada Program (EM-NV) efforts to establish post-closure monitoring plans for the Smoky Site Soils Corrective Action Unit (CAU) 550. The work is intended to confirm the likely mechanism of transport and determine the meteorological conditions that might cause the movement of contaminated soils, as well as determine the particle size fraction that is most closely associated with transported radionuclide-contaminated soils. These data will facilitate the design of the appropriate post-closure monitoring program. In 2011, DRI installed a meteorological monitoring station on the west side of the Smoky Site CA and a hydrologic (runoff) monitoring station within the CA, near the east side. Air temperature, wind speed, wind direction, relative humidity, precipitation, solar radiation, barometric pressure, soil temperature, and soil water content are collected at the meteorological station. The maximum, minimum, and average or total values (as appropriate) for each of these parameters are recorded for each 10-minute interval. The maximum, minimum, and average water depth in the flume installed at the hydrology station are also recorded for every 10-minute interval. This report presents data collected from these stations during fiscal year (FY) 2017. During the FY2017 reporting period, the warmest months were June, July, and August and the coldest were December and January. Solar radiation showed the same seasonal trend, although the months with the most solar radiation were May and June. Monthly mean wind speeds were highest in the spring (April and May). Winds were generally from the southwest during the summer and from the northwest throughout the remainder of the year. The monthly average

  12. Mercury contamination and potential impacts from municipal waste incinerator on Samui Island, Thailand.

    Science.gov (United States)

    Muenhor, Dudsadee; Satayavivad, Jutamaad; Limpaseni, Wongpun; Parkpian, Preeda; Delaune, R D; Gambrell, R P; Jugsujinda, Aroon

    2009-03-01

    In recent years, mercury (Hg) pollution generated by municipal waste incinerators (MWIs) has become the subject of serious public concern. On Samui Island, Thailand, a large-scale municipal waste incinerator has been in operation for over 7 years with a capacity of 140 tons/day for meeting the growing demand for municipal waste disposal. This research assessed Hg contamination in environmental matrices adjacent to the waste incinerating plant. Total Hg concentrations were determined in municipal solid waste, soil and sediment within a distance of 100 m to 5 km from the incinerator operation in both wet and dry seasons. Hg analyses conducted in municipal solid waste showed low levels of Hg ranging between 0.15-0.56 mg/kg. The low level was due to the type of waste incinerator. Waste such as electrical appliances, motors and spare parts, rubber tires and hospital wastes are not allowed to feed into the plant. As a result, low Hg levels were also found in fly and bottom ashes (0.1-0.4 mg/kg and Stack concentration of Hg were less than 0.4 microg/Nm(3). Since Hg emissions were at low concentrations, Hg in soil from atmospheric fallout near this incinerator including uptake by local weeds were very low ranging from non detectable to 399 micro g/kg. However, low but elevated levels of Hg (76-275 micro g/kg) were observed in surface soil and deeper layers (0-40 cm) in the predominant downwind direction of incinerator over a distance of between 0.5-5 km. Soil Hg concentrations measured from a reference/background track opposite of the prevailing wind direction were lower ranging between 7-46 micro g/kg. Nevertheless, the trend of Hg build up in soil was clearly seen in the wet season only, suggesting that wet deposition process is a major Hg pollution source. Hg concentrations in the sea bottom sediment collected next to the last station track was small with values between 35-67 micro g/kg. Based upon the overall findings, in terms of current potential environmental risk

  13. Toxicological benchmarks for screening potential contaminants of concern for effects on soil and litter invertebrates and heterotrophic process

    International Nuclear Information System (INIS)

    Will, M.E.; Suter, G.W. II.

    1994-09-01

    One of the initial stages in ecological risk assessments for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as open-quotes contaminants of potential concern.close quotes This process is termed open-quotes contaminant screening.close quotes It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to soil- and litter-dwelling invertebrates, including earthworms, other micro- and macroinvertebrates, or heterotrophic bacteria and fungi. This report presents a standard method for deriving benchmarks for this purpose, sets of data concerning effects of chemicals in soil on invertebrates and soil microbial processes, and benchmarks for chemicals potentially associated with United States Department of Energy sites. In addition, literature describing the experiments from which data were drawn for benchmark derivation. Chemicals that are found in soil at concentrations exceeding both the benchmarks and the background concentration for the soil type should be considered contaminants of potential concern

  14. Assessment of potential impacts of major groundwater contaminants to fall chinook salmon (Oncorhynchus tshawytscha) in the Hanford Reach, Columbia River

    International Nuclear Information System (INIS)

    Geist, D.R.; Poston, T.M.; Dauble, D.D.

    1994-10-01

    Past operations of Hanford Site facilities have contaminated the groundwater adjacent to the Hanford Reach of the Columbia River, Washington, with various chemical and radiological constituents. The groundwater is hydraulically connected to the river and contains concentrations of contaminants that sometimes exceed federal and/or state drinking water standards or standards for the protection of aquatic life. For example, concentrations of chromium in shoreline seeps and springs at most 100 Area operable units exceed concentrations found to be toxic to fish. Nitrate and tritium concentrations in shoreline seeps are generally below drinking water standards and concentrations potentially toxic to aquatic life, but nitrate concentrations may be high enough to synergistically interact with and exacerbate chromium toxicity. The Hanford Reach also supports the largest run of fall chinook salmon (Oncorhynchus tshawytscha) in the Columbia River Basin. Numbers of fall chinook salmon returning to the Hanford Reach have increased relative to other mainstem populations during the last 30 years. Groundwater discharge appears to occur near some salmon spawning areas, but contaminants are generally not detectable in surface water samples. The concentration and potential toxicity of contaminants in the interstitial waters of the substrate where fall chinook salmon embryogenesis occurs are presently unknown. New tools are required to characterize the extent of groundwater contaminant discharge to the Hanford Reach and to resolve uncertainties associated with assessment of potential impacts to fall chinook salmon

  15. Toxicological benchmarks for screening potential contaminants of concern for effects on soil and litter invertebrates and heterotrophic process

    Energy Technology Data Exchange (ETDEWEB)

    Will, M.E.; Suter, G.W. II

    1994-09-01

    One of the initial stages in ecological risk assessments for hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration as {open_quotes}contaminants of potential concern.{close_quotes} This process is termed {open_quotes}contaminant screening.{close_quotes} It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to soil- and litter-dwelling invertebrates, including earthworms, other micro- and macroinvertebrates, or heterotrophic bacteria and fungi. This report presents a standard method for deriving benchmarks for this purpose, sets of data concerning effects of chemicals in soil on invertebrates and soil microbial processes, and benchmarks for chemicals potentially associated with United States Department of Energy sites. In addition, literature describing the experiments from which data were drawn for benchmark derivation. Chemicals that are found in soil at concentrations exceeding both the benchmarks and the background concentration for the soil type should be considered contaminants of potential concern.

  16. Potential impact of soil microbial heterogeneity on the persistence of hydrocarbons in contaminated subsurface soils.

    Science.gov (United States)

    Aleer, Sam; Adetutu, Eric M; Weber, John; Ball, Andrew S; Juhasz, Albert L

    2014-04-01

    In situ bioremediation is potentially a cost effective treatment strategy for subsurface soils contaminated with petroleum hydrocarbons, however, limited information is available regarding the impact of soil spatial heterogeneity on bioremediation efficacy. In this study, we assessed issues associated with hydrocarbon biodegradation and soil spatial heterogeneity (samples designated as FTF 1, 5 and 8) from a site in which in situ bioremediation was proposed for hydrocarbon removal. Test pit activities showed similarities in FTF soil profiles with elevated hydrocarbon concentrations detected in all soils at 2 m below ground surface. However, PCR-DGGE-based cluster analysis showed that the bacterial community in FTF 5 (at 2 m) was substantially different (53% dissimilar) and 2-3 fold more diverse than communities in FTF 1 and 8 (with 80% similarity). When hydrocarbon degrading potential was assessed, differences were observed in the extent of (14)C-benzene mineralisation under aerobic conditions with FTF 5 exhibiting the highest hydrocarbon removal potential compared to FTF 1 and 8. Further analysis indicated that the FTF 5 microbial community was substantially different from other FTF samples and dominated by putative hydrocarbon degraders belonging to Pseudomonads, Xanthomonads and Enterobacteria. However, hydrocarbon removal in FTF 5 under anaerobic conditions with nitrate and sulphate electron acceptors was limited suggesting that aerobic conditions were crucial for hydrocarbon removal. This study highlights the importance of assessing available microbial capacity prior to bioremediation and shows that the site's spatial heterogeneity can adversely affect the success of in situ bioremediation unless area-specific optimizations are performed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Use of liquid nitrogen during storage in a cell and tissue bank: contamination risk and effect on the detectability of potential viral contaminants.

    Science.gov (United States)

    Mirabet, Vicente; Alvarez, Manuel; Solves, Pilar; Ocete, Dolores; Gimeno, Concepción

    2012-04-01

    Cryopreservation is widely used for banking cells and tissues intended for transplantation. Liquid nitrogen provides a very stable ultra-low temperature environment. Thus, it is used for longterm storage. Unlike the exhaustive microbiological monitoring of the environmental conditions during tissue processing, storage is not usually considered as a critical point of potential contamination risk in professional standards for cell and tissue banking. We have analysed the presence of microbial agents inside our nitrogen tanks. We have mainly detected environmental and water-borne bacteria and fungi. In addition, we have studied the effect of liquid nitrogen exposure on virus detectability. Only differences for hepatitis C virus RNA were observed. Measures for contamination risk reduction during storage must be mandatory in cell and tissue banking. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Risks to Ecological Receptors Posed by Contaminants of Potential Concern in the Lower Three Runs Cooling Ponds and Canals

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Blas, S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-03-21

    The upper portion of Lower Three Runs includes several ponds, reservoirs, and canals that were formerly used as a cooling system for nuclear production reactors. This area was divided into nine exposure areas (EAs) for the assessment of environmental contamination resulting from past reactor operations and other industrial processes. A tiered screening process identified several contaminants of potential concern including aluminum, cyanide, lead, manganese, mercury, DDD, DDE, and DDT. Risks posed by these contaminants to ecological receptors (river otter, belted kingfisher, raccoon, and blue heron) were assessed using contaminant exposure models that estimated contaminant intake resulting from ingestion of food, water, and sediment/ soil and compared these intakes with toxicity reference values (TRVs). The contaminant exposure models showed that the TRVs were not exceeded in the otter model, exceeded by aluminum in EA 7 (Pond 2 and associated canals) in the raccoon model, and exceeded by mercury in EAs 2, 3 (Pond B), 6 (Par Pond), and 8 (Ponds 4 and 5 and Canal to Pond C) in both the kingfisher and blue heron models. Hazard quotients (total exposure dose divided by the TRV) were 2.8 for aluminum and 1.7- 3.6 for mercury. The primary route of exposure for aluminum was the ingestion of soil, and the primary route of exposure for mercury was the ingestion of mercury contaminated fish. Elevated levels of mercury in fish were at least partly the result of the aerial deposition of mercury onto Lower Three Runs and its watershed. The atmospheric deposition of mercury creates pervasive contamination in fish throughout the Savannah River basin. Another possible source of mercury was the discharge of mercury contaminated Savannah River water into the Lower Three Runs cooling ponds and canals during previous years of reactor operation. This contamination originated from industries located upstream of the SRS. The aluminum exceedance for the raccoon was likely the result of

  19. Assessing the Potential for Inland Migration of a Northeastern Salt Marsh

    Science.gov (United States)

    Farron, S.; FitzGerald, D.; Hughes, Z. J.

    2017-12-01

    It is often assumed that as sea level rises, salt marshes will expand inland. If the slope of the upland is relatively flat and sufficient sediment is available, marshes should be able to spread horizontally and grow vertically in order to maintain their areal extent. However, in cases where marshes are backed by steeper slopes, or sediment supply is limited, rising sea level will produce minimal gains along the landward edge insufficient to offset potential losses along the seaward edge. This study uses future sea level rise scenarios to project areal losses for the Great Marsh in Massachusetts, the largest continuous salt marsh in New England. Land area covered by salt marsh is defined by surface elevation. Annual sediment input to the system is estimated based on the areal extent of high and low marsh, historical accretion rates for each, and known organic/inorganic ratios. Unlike other studies, sediment availability is considered to be finite, and future accretion rates are limited based on the assumption that the system is presently receiving the maximum sediment input available. The Great Marsh is dominated by high marsh; as sea level rises, it will convert to low marsh, vastly altering the ecological and sedimentological dynamics of the system. If it is assumed that former high marsh areas will build vertically at the increased rate associated with low marsh, then much of the total marsh area will be maintained. However, this may be an unrealistic assumption due to the low levels of suspended sediment within the Great Marsh system. Modeling the evolution of the Great Marsh by assuming that the current accretion rate is the maximum possible for this system reveals much greater losses than models assuming an unlimited sediment supply would predict (17% less marsh by 2115). In addition, uplands surrounding the Great Marsh have been shaped by glaciation, leaving numerous drumlins and other glacial landforms. Compared to the flat backbarrier, the surrounding

  20. Potential external contamination with bisphenol A and other ubiquitous organic environmental chemicals during biomonitoring analysis: an elusive laboratory challenge.

    Science.gov (United States)

    Ye, Xiaoyun; Zhou, Xiaoliu; Hennings, Ryan; Kramer, Joshua; Calafat, Antonia M

    2013-03-01

    Biomonitoring studies are conducted to assess internal dose (i.e., body burden) to environmental chemicals. However, because of the ubiquitous presence in the environment of some of these chemicals, such as bisphenol A (BPA), external contamination during handling and analysis of the biospecimens collected for biomonitoring evaluations could compromise the reported concentrations of such chemicals. We examined the contamination with the target analytes during analysis of biological specimens in biomonitoring laboratories equipped with state-of-the-art analytical instrumentation. We present several case studies using the quantitative determination of BPA and other organic chemicals (i.e., benzophenone-3, triclosan, parabens) in human urine, milk, and serum to identify potential contamination sources when the biomarkers measured are ubiquitous environmental contaminants. Contamination with target analytes during biomonitoring analysis could result from solvents and reagents, the experimental apparatus used, the laboratory environment, and/or even the analyst. For biomonotoring data to be valid-even when obtained from high-quality analytical methods and good laboratory practices-the following practices must be followed to identify and track unintended contamination with the target analytes during analysis of the biological specimens: strict quality control measures including use of laboratory blanks; replicate analyses; engineering controls (e.g., clean rooms, biosafety cabinets) as needed; and homogeneous matrix-based quality control materials within the expected concentration ranges of the study samples.

  1. The Potential Use of Vetiveria zizanioides for the Phytoremediation of Antimony, Arsenic and Their Co-Contamination.

    Science.gov (United States)

    Mirza, Nosheen; Mubarak, Hussani; Chai, Li-Yuan; Yong, Wang; Khan, Muhammad Jamil; Khan, Qudrat Ullah; Hashmi, Muhammad Zaffar; Farooq, Umar; Sarwar, Rizwana; Yang, Zhi-Hui

    2017-10-01

    Antimony (Sb) and arsenic (As) contaminations are the well reported and alarming issues of various contaminated smelting and mining sites all over the world, especially in China. The present hydroponic study was to assess the capacity of Vetiveria zizanioides for Sb, As and their interactive accumulations. The novelty of the present research is this that the potential of V. zizanioides for Sb and As alone and their interactive accumulation are unaddressed. This is the first report about the interactive co-accumulation of Sb and As in V. zizanioides. Highest applied Sb and As contaminations significantly inhibited the plant growth. Applied Sb and As alone significantly increased their concentrations in the roots/shoot of V. zizanioides. While co-contamination of Sb and As steadily increased their concentrations, in the plant. The co-contamination of Sb and As revealed a positive correlation between the two, as they supplemented the uptake and accumulation of each other. The overall translocation (TF) and bioaccumulation factors (BF) of Sb in V. zizanioides, were 0.75 and 4. While the TF and BF of As in V. zizanioides, were 0.86 and 10. V. zizanioides proved as an effective choice for the phytoremediation and ecosystem restoration of Sb and As contaminated areas.

  2. Potential Use of Polyacrylamide Encapsulation for Treatment of Petroleum Drilling Cuttings and Hydrocarbon Contaminated Soil

    Directory of Open Access Journals (Sweden)

    Randy H. Adams

    2011-07-01

    Full Text Available Mineral soil of alluvial origin, contaminated with diesel+lubricating oil (1:2, was treated with a commercial polyacrylamide product at 100 % of the distributer recommended dosage, producing a reduction in hydrocarbon concentration (EPA 9074 of 76 % that remained stable during the study period (38 days and even after thermal treatment (60 ºC, 18 hrs.. Increasing the dosage to 150 % did not improve the treatment results, but repeating the treatment (at 100 % resulted in a slight additional reduction (4 %. Similar results were obtained with oil-based drilling cuttings (~60 % reduction at both 100 % and 150 %. Pre-drying of the drilling cuttings prior to treatment did not improve the hydrocarbon reduction, but it did produce smaller, potentially more stable aggregates (0.5 – 1-0 mm in diameter. The treatment of organic soil resulted in a similar reduction in hydrocarbon concentration (65 % and a reduction of acute toxicity (Microtox to below background levels, however this effect was not stable. An additional application (including mixing of the polyacrylamide product resulted in partial disintegration of the organic fibres and release of the stabilized hydrocarbons, measuring an overall increase in hydrocarbon concentration of 19 %.

  3. Phytoremediation potential of Arundo donax in arsenic-contaminated synthetic wastewater.

    Science.gov (United States)

    Mirza, Nosheen; Mahmood, Qaisar; Pervez, Arshid; Ahmad, Raza; Farooq, Robina; Shah, Mohammad Maroof; Azim, Muhammad Rashid

    2010-08-01

    The present study reports the potential of Arundo donax for phytoextraction of arsenic from synthetic wastewater. A. donax plants were grown under greenhouse conditions in pots containing a nutrient solution amended with increasing doses of As (0, 50, 100, 300, 600 and 1000 microg L(-1)) for 21 days in a completely randomized design. Shoot and roots dry matter production, growth parameters, arsenic and nutrient tissue concentrations were measured at the end of the experiment. Increasing As concentration in nutrient solution caused an increase in shoot and root biomass without toxicity symptoms in A. donax growing under a range of As concentration from 50 to 600 microg L(-1). Elevated oxidative stress was observed at As supplied level of 1000 microg L(-1). The As doses up to 600 microg L(-1) did not affect the growth of A. donax. It is suggested that A. donax plants may be employed to treat contaminated waters containing arsenic concentrations up to 600 microg L(-1). (c) 2010 Elsevier Ltd. All rights reserved.

  4. Potential Use of Apple Polyphenol Oxidase for Bioremediation of Phenolic Contaminants

    Directory of Open Access Journals (Sweden)

    Anita Šalić

    2018-04-01

    Full Text Available Phenolic compounds, such as catechol, are released into the environment from a variety of industrial sources and they present a serious ecosystem burden. This work examined the possibility of using partially purified apple polyphenol oxidase (PPO for bioremediation of phenolic contaminants. In order to optimize process conditions, the optimal pH and temperature for PPO activity were determined, while PPO affinity toward various phenols, as well as the effect of some salts and organic solvents which can be found in wastewaters, was used to confirm applicability of PPO in wastewater treatment. It was found that partially purified apple PPO shows maximal activity at pH 6.8 and 25 °C, but exhibits more than 85 % of its maximal activity in pH range from 5 to 8, and more than 90 % of activity in temperature range from 10 to 50 °C. PPO showed high affinity for various diphenols, but lack of affinity toward monophenols. Sodium tetraborate decahydrate moderately inhibited PPO activity, while exposure of PPO to the presence of organic solvents (φ = 5 % caused 40 % loss in its activity. Catechol oxidation by PPO performed for just 5 min in a batch reactor at optimal process conditions resulted in 25 % conversion. Based on obtained data, it seems that partially purified apple PPO has reasonable potential in wastewater treatment.

  5. Assessment of the genotoxic potential of contaminated estuarine sediments in fish peripheral blood: Laboratory versus in situ studies

    International Nuclear Information System (INIS)

    Costa, Pedro M.; Neuparth, Teresa S.; Caeiro, Sandra; Lobo, Jorge; Martins, Marta; Ferreira, Ana M.; Caetano, Miguel; Vale, Carlos; Angel DelValls, T.; Costa, Maria H.

    2011-01-01

    Juvenile Senegalese soles (Solea senegalensis) were exposed to estuarine sediments through 28-day laboratory and in situ (field) bioassays. The sediments, collected from three distinct sites (a reference plus two contaminated) of the Sado Estuary (W Portugal) were characterized for total organic matter, redox potential, fine fraction and for the levels of metals, polycyclic aromatic hydrocarbons (PAHs) and organochlorines, namely polychlorinated biphenyls (PCBs) and dichloro diphenyl tricholoethane plus its main metabolites (DDTs). Genotoxicity was determined in whole peripheral blood by the single-cell gel electrophoresis (SCGE or 'comet') assay and by scoring erythrocytic nuclear abnormalities (ENA). Analysis was complemented with the determination of lipid peroxidation in blood plasma by the thiobarbituric acid reactive substances (TBARS) protocol and cell type sorting. The results showed that exposure to contaminated sediments induced DNA fragmentation and clastogenesis. Still, laboratory exposure to the most contaminated sediment revealed a possible antagonistic effect between metallic and organic contaminants that might have been enhanced by increased bioavailability. The laboratory assay caused a more pronounced increase in ENA whereas a very significant increase in DNA fragmentation was observed in field-tested fish exposed to the reference sediment, which is likely linked to increased lipid peroxidation that probably occurred due to impaired access to food. Influence of natural pathogens was ruled out by unaltered leukocyte counts. The statistical integration of data correlated lipid peroxidation with biological variables such as fish length and weight, whereas the genotoxicity biomarkers were more correlated to sediment contamination. It was demonstrated that laboratory and field bioassays for the risk assessment of sediment contamination may yield different genotoxicity profiles although both provided results that are in overall accordance with sediment

  6. Potential of coconut shell activated carbon (CSAC) in removing contaminants for water quality improvement: A critical review

    Science.gov (United States)

    Akhir, Muhammad Fitri Mohd; Saad, Noor Aida; Zakaria, Nor Azazi

    2017-10-01

    Commonly, water contaminations occur due to human-induced conditions such as industrial discharge and urban activities. The widely identified contaminants are heavy metal. The toxicity of those heavy metal elements is high and very poisonous to humans' health and environment even at lower dose or concentration of exposure. Chronic poisoning can cause fatal or defect to one's body or environment. Organic contaminants such as oil and microbial are also found due to decomposition of organic matter. The excellent quality adsorption of contaminants is highly related to surface area, pore size, pore volume, and amount plus type of functional group on surface of CSAC. The higher the surface area and pore volume, the higher adsorption that CSAC have towards contaminants. In comparison to meso-pore and macro-pore, micro-pore is better for trapping and adsorbing water contaminants. The purpose of this article is to critically review the potential of CSAC in increasing adsorption to remove contaminants for water quality improvement. A critical review is implemented using search engine like Science Direct. Alkali-modification is shown to have good adsorption in anion elements and organic matter due to improvement of hydrophobic organic compound (HOC) while acid-modification is good in cation elements adsorption. Strong alkali impregnated solution makes CSAC more hydrophobic and positively charge especially after increasing the impregnation dosage. Strong acid of adsorbate affects the quality of adsorption by reducing the surface area, pore volume and it also breaks the Van der Waals forces between adsorbent and adsorbate. However, the formation of oxygen helps the activated carbon surface to become more hydrophilic and negative charge is produced. It helps the effectiveness of metal adsorption. Therefore, by controlling dosage and types of functional groups on surface of CSAC and the pH of adsorbate, it can contribute to high adsorption of organic and inorganic contaminants in

  7. Assessment of the genotoxic potential of contaminated estuarine sediments in fish peripheral blood: Laboratory versus in situ studies

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Pedro M., E-mail: pmcosta@fct.unl.pt [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Neuparth, Teresa S. [CIIMAR-Centro Interdisciplinar de Investigacao Marinha e Ambiental, Laboratorio de Toxicologia Ambiental, Universidade do Porto, Rua dos Bragas 289, 4050-123 Porto (Portugal); Caeiro, Sandra [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Departamento de Ciencias e Tecnologia, Universidade Aberta, Rua da Escola Politecnica, 141, 1269-001 Lisboa (Portugal); Lobo, Jorge [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Martins, Marta; Ferreira, Ana M.; Caetano, Miguel; Vale, Carlos [IPIMAR-INRB, Instituto Nacional dos Recursos Biologicos, Avenida de Brasilia, 1449-006 Lisboa (Portugal); Angel DelValls, T. [UNESCO/UNITWIN/WiCop Chair-Departamento de Quimica Fisica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cadiz, Poligono rio San Pedro s/n, 11510 Puerto Real, Cadiz (Spain); Costa, Maria H. [IMAR-Instituto do Mar, Departamento de Ciencias e Engenharia do Ambiente, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2011-01-15

    Juvenile Senegalese soles (Solea senegalensis) were exposed to estuarine sediments through 28-day laboratory and in situ (field) bioassays. The sediments, collected from three distinct sites (a reference plus two contaminated) of the Sado Estuary (W Portugal) were characterized for total organic matter, redox potential, fine fraction and for the levels of metals, polycyclic aromatic hydrocarbons (PAHs) and organochlorines, namely polychlorinated biphenyls (PCBs) and dichloro diphenyl tricholoethane plus its main metabolites (DDTs). Genotoxicity was determined in whole peripheral blood by the single-cell gel electrophoresis (SCGE or 'comet') assay and by scoring erythrocytic nuclear abnormalities (ENA). Analysis was complemented with the determination of lipid peroxidation in blood plasma by the thiobarbituric acid reactive substances (TBARS) protocol and cell type sorting. The results showed that exposure to contaminated sediments induced DNA fragmentation and clastogenesis. Still, laboratory exposure to the most contaminated sediment revealed a possible antagonistic effect between metallic and organic contaminants that might have been enhanced by increased bioavailability. The laboratory assay caused a more pronounced increase in ENA whereas a very significant increase in DNA fragmentation was observed in field-tested fish exposed to the reference sediment, which is likely linked to increased lipid peroxidation that probably occurred due to impaired access to food. Influence of natural pathogens was ruled out by unaltered leukocyte counts. The statistical integration of data correlated lipid peroxidation with biological variables such as fish length and weight, whereas the genotoxicity biomarkers were more correlated to sediment contamination. It was demonstrated that laboratory and field bioassays for the risk assessment of sediment contamination may yield different genotoxicity profiles although both provided results that are in overall accordance with

  8. Radioactive contamination in the Arctic--sources, dose assessment and potential risks

    International Nuclear Information System (INIS)

    Strand, P.; Howard, B.J.; Aarkrog, A.; Balonov, M.; Tsaturov, Y.; Bewers, J.M.; Salo, A.; Sickel, M.; Bergman, R.; Rissanen, K.

    2002-01-01

    Arctic residents, whose diets comprise a large proportion of traditional terrestrial and freshwater foodstuffs, have received the highest radiation exposures to artificial radionuclides in the Arctic. Doses to members of both the average population and selected indigenous population groups in the Arctic depend on the rates of consumption of locally-derived terrestrial and freshwater foodstuffs, including reindeer/caribou meat, freshwater fish, goat cheese, berries, mushrooms and lamb. The vulnerability of arctic populations, especially indigenous peoples, to radiocaesium deposition is much greater than for temperate populations due to the importance of terrestrial, semi-natural exposure pathways where there is high radiocaesium transfer and a long ecological half-life for this radionuclide. In contrast, arctic residents with diets largely comprising marine foodstuffs have received comparatively low radiation exposures because of the lower levels of contamination of marine organisms. Using arctic-specific information, the predicted collective dose is five times higher than that estimated by UNSCEAR for temperate areas. The greatest threats to human health and the environment posed by human and industrial activities in the Arctic are associated with the potential for accidents in the civilian and military nuclear sectors. Of most concern are the consequences of potential accidents in nuclear power plant reactors, during the handling and storage of nuclear weapons, in the decommissioning of nuclear submarines and in the disposal of spent nuclear fuel from vessels. It is important to foster a close association between risk assessment and practical programmes for the purposes of improving monitoring, formulating response strategies and implementing action plans

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  10. Evaluation of metal contamination and phytoremediation potential of aquatic macrophytes of East Kolkata Wetlands, India.

    Science.gov (United States)

    Khatun, Amina; Pal, Sandipan; Mukherjee, Aloke Kumar; Samanta, Palas; Mondal, Subinoy; Kole, Debraj; Chandra, Priyanka; Ghosh, Apurba Ratan

    2016-01-01

    The present study analyzes metal contamination in sediment of the East Kolkata Wetlands, a Ramsar site, which is receiving a huge amount of domestic and industrial wastewater from surrounding areas. The subsequent uptake and accumulation of metals in different macrophytes are also examined in regard to their phytoremediation potential. Metals like cadmium (Cd), copper (Cu), manganese (Mn), and lead (Pb) were estimated in sediment, water and different parts of the macrophytes Colocasia esculenta and Scirpus articulatus . The concentration of metals in sediment were, from highest to lowest, Mn (205.0±65.5 mg/kg)>Cu (29.9±10.2 mg/kg)>Pb (22.7±10.3 mg/kg)>Cd (3.7±2.2 mg/kg). The phytoaccumulation tendency of these metals showed similar trends in both native aquatic macrophyte species. The rate of accumulation of metals in roots was higher than in shoots. There were strong positive correlations ( p <0.001) between soil organic carbon (OC) percentage and Mn (r =0.771), and sediment OC percentage and Pb (r=0.832). Cation exchange capacity (CEC) also showed a positive correlation ( p <0.001) with Cu (r=0.721), Mn (r=0.713), and Pb (r=0.788), while correlations between sediment OC percentage and Cu (r=0.628), sediment OC percentage and Cd (r=0.559), and CEC and Cd (r=0.625) were significant at the p <0.05 level. Bioaccumulation factor and translocation factors of these two plants revealed that S. articulatus was comparatively more efficient for phytoremediation, whereas phytostabilization potential was higher in C. esculenta .

  11. Microbial detoxification of bifenthrin by a novel yeast and its potential for contaminated soils treatment.

    Directory of Open Access Journals (Sweden)

    Shaohua Chen

    Full Text Available Bifenthrin is one the most widespread pollutants and has caused potential effect on aquatic life and human health, yet little is known about microbial degradation in contaminated regions. A novel yeast strain ZS-02, isolated from activated sludge and identified as Candida pelliculosa based on morphology, API test and 18S rDNA gene analysis, was found highly effective in degrading bifenthrin over a wide range of temperatures (20-40 °C and pH (5-9. On the basis of response surface methodology (RSM, the optimal degradation conditions were determined to be 32.3 °C and pH 7.2. Under these conditions, the yeast completely metabolized bifenthrin (50 mg · L(-1 within 8 days. This strain utilized bifenthrin as the sole carbon source for growth as well as co-metabolized it in the presence of glucose, and tolerated concentrations as high as 600 mg · L(-1 with a q(max, K(s and K(i of 1.7015 day(-1, 86.2259 mg · L(-1 and 187.2340 mg · L(-1, respectively. The yeast first degraded bifenthrin by hydrolysis of the carboxylester linkage to produce cyclopropanecarboxylic acid and 2-methyl-3-biphenylyl methanol. Subsequently, 2-methyl-3-biphenylyl methanol was further transformed by biphenyl cleavage to form 4-trifluoromethoxy phenol, 2-chloro-6-fluoro benzylalcohol, and 3,5-dimethoxy phenol, resulting in its detoxification. Eventually, no persistent accumulative product was detected by gas chromatopraphy-mass spectrometry (GC-MS analysis. This is the first report of a novel pathway of degradation of bifenthrin by hydrolysis of ester linkage and cleavage of biphenyl in a microorganism. Furthermore, strain ZS-02 degraded a variety of pyrethroids including bifenthrin, cyfluthrin, deltamethrin, fenvalerate, cypermethrin, and fenpropathrin. In different contaminated soils introduced with strain ZS-02, 65-75% of the 50 mg · kg(-1 bifenthrin was eliminated within 10 days, suggesting the yeast could be a promising candidate for remediation of environments affected

  12. Microbial detoxification of bifenthrin by a novel yeast and its potential for contaminated soils treatment.

    Science.gov (United States)

    Chen, Shaohua; Luo, Jianjun; Hu, Meiying; Geng, Peng; Zhang, Yanbo

    2012-01-01

    Bifenthrin is one the most widespread pollutants and has caused potential effect on aquatic life and human health, yet little is known about microbial degradation in contaminated regions. A novel yeast strain ZS-02, isolated from activated sludge and identified as Candida pelliculosa based on morphology, API test and 18S rDNA gene analysis, was found highly effective in degrading bifenthrin over a wide range of temperatures (20-40 °C) and pH (5-9). On the basis of response surface methodology (RSM), the optimal degradation conditions were determined to be 32.3 °C and pH 7.2. Under these conditions, the yeast completely metabolized bifenthrin (50 mg · L(-1)) within 8 days. This strain utilized bifenthrin as the sole carbon source for growth as well as co-metabolized it in the presence of glucose, and tolerated concentrations as high as 600 mg · L(-1) with a q(max), K(s) and K(i) of 1.7015 day(-1), 86.2259 mg · L(-1) and 187.2340 mg · L(-1), respectively. The yeast first degraded bifenthrin by hydrolysis of the carboxylester linkage to produce cyclopropanecarboxylic acid and 2-methyl-3-biphenylyl methanol. Subsequently, 2-methyl-3-biphenylyl methanol was further transformed by biphenyl cleavage to form 4-trifluoromethoxy phenol, 2-chloro-6-fluoro benzylalcohol, and 3,5-dimethoxy phenol, resulting in its detoxification. Eventually, no persistent accumulative product was detected by gas chromatopraphy-mass spectrometry (GC-MS) analysis. This is the first report of a novel pathway of degradation of bifenthrin by hydrolysis of ester linkage and cleavage of biphenyl in a microorganism. Furthermore, strain ZS-02 degraded a variety of pyrethroids including bifenthrin, cyfluthrin, deltamethrin, fenvalerate, cypermethrin, and fenpropathrin. In different contaminated soils introduced with strain ZS-02, 65-75% of the 50 mg · kg(-1) bifenthrin was eliminated within 10 days, suggesting the yeast could be a promising candidate for remediation of environments affected by

  13. A holistic passive integrative sampling approach for assessing the presence and potential impacts of waterborne environmental contaminants

    Science.gov (United States)

    Petty, J.D.; Huckins, J.N.; Alvarez, D.A.; Brumbaugh, W. G.; Cranor, W.L.; Gale, R.W.; Rastall, A.C.; Jones-Lepp, T. L.; Leiker, T.J.; Rostad, C. E.; Furlong, E.T.

    2004-01-01

    As an integral part of our continuing research in environmental quality assessment approaches, we have developed a variety of passive integrative sampling devices widely applicable for use in defining the presence and potential impacts of a broad array of contaminants. The semipermeable membrane device has gained widespread use for sampling hydrophobic chemicals from water and air, the polar organic chemical integrative sampler is applicable for sequestering waterborne hydrophilic organic chemicals, the stabilized liquid membrane device is used to integratively sample waterborne ionic metals, and the passive integrative mercury sampler is applicable for sampling vapor phase or dissolved neutral mercury species. This suite of integrative samplers forms the basis for a new passive sampling approach for assessing the presence and potential toxicological significance of a broad spectrum of environmental contaminants. In a proof-of-concept study, three of our four passive integrative samplers were used to assess the presence of a wide variety of contaminants in the waters of a constructed wetland, and to determine the effectiveness of the constructed wetland in removing contaminants. The wetland is used for final polishing of secondary-treatment municipal wastewater and the effluent is used as a source of water for a state wildlife area. Numerous contaminants, including organochlorine pesticides, polycyclic aromatic hydrocarbons, organophosphate pesticides, and pharmaceutical chemicals (e.g., ibuprofen, oxindole, etc.) were detected in the wastewater. Herein we summarize the results of the analysis of the field-deployed samplers and demonstrate the utility of this holistic approach.

  14. Investigation of soil potentially contaminated by monazite processing by-products: case study and suggestion for protocol

    International Nuclear Information System (INIS)

    Briquet, Claudia

    2006-01-01

    This work describes a characterization of soil potentially contaminated by monazite chemical processing residues. For case study it was selected a country area of Sao Paulo State, containing a monazite processing by-product depository. The main objective was to evaluate the soil contamination in an area of approximately 18,000 m 2 and esteem the total effective dose equivalent. During the development of this work, it was verified necessity of an investigation protocol, in order to standardize actions of regulatory authorities. A survey of the applicable legislation was carried out, as a tool to support decision making process. The methodology was based on the 'Manual de Gerenciamento de Areas Contaminadas' of CETESB (2001 a), a national document to guide studies of contaminated areas. It was also considered the 'Multi Agency Radiation Survey and Site Manual Investigation - MARSSIM' (2000), a U.S. government document that provides a nationally consensus approach to conduct investigations at potentially contaminated sites. The developed activities had been divided in three general stages: data-collecting and information on the place, identification of soil contamination and its distribution until the depth of 3 meters and evaluation of the associated dose. The evaluation of the radiological impact was carried out considering the worst-case use scenario (most restrictive future use), standing out that the final decision fits to the Brazilian National Nuclear Energy Commission - CNEN. CNEN's scope of responsibility includes determining the site release criteria and the cleanup necessity. (author)

  15. Pedagogical Potential of a Web-Based GIS Application for Migration Data: A Preliminary Investigation in the Context of South Korea

    Science.gov (United States)

    Kim, Minsung; Kim, Kamyoung; Lee, Sang-Il

    2013-01-01

    This article examines the pedagogical potential of a Web-based GIS application, Population Migration Web Service (PMWS), in which students can examine population geography in an interactive and exploratory manner. This article introduces PMWS, a tailored, unique Internet GIS application that provides functions for visualizing spatial interaction…

  16. Compilation of data to estimate groundwater migration potential for constituents in active liquid discharges at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Ames, L.L.; Serne, R.J.

    1991-03-01

    A preliminary characterization of the constituents present in the 33 liquid waste streams at the US Department of Energy's Hanford Site has been completed by Westinghouse Hanford Company. In addition, Westinghouse Hanford has summarized the soil characteristics based on drill logs collected at each site that receives these liquid wastes. Literature searches were conducted and available Hanford-specific data were tabulated and reviewed. General literature on organic chemicals present in the liquid waste streams was also reviewed. Using all of this information, Pacific Northwest Laboratory has developed a best estimate of the transport characteristics (water solubility and soil adsorption properties) for those radionuclides and inorganic and organic chemicals identified in the various waste streams. We assume that the potential for transport is qualified through the four geochemical parameters: solubility, distribution coefficient, persistence (radiogenic or biochemical half-life), and volatility. Summary tables of these parameters are presented for more than 50 inorganic and radioactive species and more than 50 organic compounds identified in the liquid waste streams. Brief descriptions of the chemical characteristics of Hanford sediments, solubility, and adsorption processes, and of how geochemical parameters are used to estimate migration in groundwater-sediment environments are also presented. Groundwater monitoring data are tabulated for wells neighboring the facilities that receive the liquid wastes. 91 refs., 16 figs., 23 tabs.

  17. Reducing the potential for migration of radioactive waste: Aqueous thermal degradation of the chelating agent disodium EDTA

    International Nuclear Information System (INIS)

    Boles, J.S.; Ritchie, K.; Crerar, D.A.

    1987-01-01

    Ethylenediaminetetraacetic acid (EDTA), a common component of cleaning solutions used for decontamination of radioactive equipment, has been associated with increased migration of radionuclides into local groundwaters at some radwaste disposal sites. It has been proposed that predisposal thermal degradation of EDTA-containing aqueous solutions may reduce the potential for chelate-enhanced mobilization of radionuclides at these sites. Aqueous thermal degradation experiments with disodium EDTA have shown that the compound degrades rapidly at 200 0 C with an activation energy of 114.3 +- 7.87 kJ/mol, and forms the decomposition product methyliminodiacetic acid (MIDA). A comparison of the values for stability constants of transition metal and actinide complexes with EDTA, MIDA, and two other reported degradation products, indicates that the chelating efficiency of the degradation products is 6 to 22 orders of magnitude lower than that of EDTA at 25 0 C. It is concluded that aqueous thermal degradation should significantly reduce the overall chelating efficiency of EDTA-containing solutions

  18. Compilation of data to estimate groundwater migration potential for constituents in active liquid discharges at the Hanford Site

    International Nuclear Information System (INIS)

    Ames, L.L.; Serne, R.J.

    1991-03-01

    A preliminary characterization of the constituents present in the 33 liquid waste streams at the US Department of Energy's Hanford Site has been completed by Westinghouse Hanford Company. In addition, Westinghouse Hanford has summarized the soil characteristics based on drill logs collected at each site that receives these liquid wastes. Literature searches were conducted and available Hanford-specific data were tabulated and reviewed. General literature on organic chemicals present in the liquid waste streams was also reviewed. Using all of this information, Pacific Northwest Laboratory has developed a best estimate of the transport characteristics (water solubility and soil adsorption properties) for those radionuclides and inorganic and organic chemicals identified in the various waste streams. We assume that the potential for transport is qualified through the four geochemical parameters: solubility, distribution coefficient, persistence (radiogenic or biochemical half-life), and volatility. Summary tables of these parameters are presented for more than 50 inorganic and radioactive species and more than 50 organic compounds identified in the liquid waste streams. Brief descriptions of the chemical characteristics of Hanford sediments, solubility, and adsorption processes, and of how geochemical parameters are used to estimate migration in groundwater-sediment environments are also presented. Groundwater monitoring data are tabulated for wells neighboring the facilities that receive the liquid wastes. 91 refs., 16 figs., 23 tabs

  19. HGF potentiates extracellular matrix-driven migration of human myoblasts: involvement of matrix metalloproteinases and MAPK/ERK pathway.

    Science.gov (United States)

    González, Mariela Natacha; de Mello, Wallace; Butler-Browne, Gillian S; Silva-Barbosa, Suse Dayse; Mouly, Vincent; Savino, Wilson; Riederer, Ingo

    2017-10-10

    The hepatocyte growth factor (HGF) is required for the activation of muscle progenitor cells called satellite cells (SC), plays a role in the migration of proliferating SC (myoblasts), and is present as a soluble factor during muscle regeneration, along with extracellular matrix (ECM) molecules. In this study, we aimed at determining whether HGF is able to interact with ECM proteins, particularly laminin 111 and fibronectin, and to modulate human myoblast migration. We evaluated the expression of the HGF-receptor c-Met, laminin, and fibronectin receptors by immunoblotting, flow cytometry, or immunofluorescence and used Transwell assays to analyze myoblast migration on laminin 111 and fibronectin in the absence or presence of HGF. Zymography was used to check whether HGF could modulate the production of matrix metalloproteinases by human myoblasts, and the activation of MAPK/ERK pathways was evaluated by immunoblotting. We demonstrated that human myoblasts express c-Met, together with laminin and fibronectin receptors. We observed that human laminin 111 and fibronectin have a chemotactic effect on myoblast migration, and this was synergistically increased when low doses of HGF were added. We detected an increase in MMP-2 activity in myoblasts treated with HGF. Conversely, MMP-2 inhibition decreased the HGF-associated stimulation of cell migration triggered by laminin or fibronectin. HGF treatment also induced in human myoblasts activation of MAPK/ERK pathways, whose specific inhibition decreased the HGF-associated stimulus of cell migration triggered by laminin 111 or fibronectin. We demonstrate that HGF induces ERK phosphorylation and MMP production, thus stimulating human myoblast migration on ECM molecules. Conceptually, these data state that the mechanisms involved in the migration of human myoblasts comprise both soluble and insoluble moieties. This should be taken into account to optimize the design of therapeutic cell transplantation strategies by improving

  20. Analysis of the potential of building ramps in hydrotechnical structures as a means of facilitating fish migration

    Directory of Open Access Journals (Sweden)

    Tomasz Tymiński

    2016-09-01

    Full Text Available Measures aimed at preserving “ecological corridors” in rivers are a difficult and complex issue that requires specialized knowledge from many science disciplines. Fishways are one of the most important solutions that ensure the ecological continuity of rivers for fish, particularly due to their near-natural design. A characteristic feature of their construction is the use of natural building materials (stones, tree stumps, gravel, and vegetation in such a way that their appearance resembles asmall watercourse. The design of hydraulic fishways is based only on the criterion of maximum speed (vmax and the parameter of unitary energy of water E; it does not provide complete information about these devices’ efficiency. In order to produce optimal flow conditions for ichthyofauna in the fishway, there is a need for research into the spatial distribution of the hydraulic parameters, such as disorders of the flow velocity field or distributions of turbulence (Tu. The aim and scope of this work was to examine the potential of building fish ramps as a means of creating a watercourse through hydrotechnical structures, in order to facilitate fish migration. For this purpose, research was conducted on a physical model in the water laboratory of Prof. Julian Wołoszyn at the Wrocław University of Environmental and Life Sciences. A physical model of a fish ramp was built. Depths and flow speeds at the established water flow rate were measured. Depths of water in the fishway were evaluated in strategic places for fish – i.e. at the entrance and exit of the fishway and between cylindric stones (flow obstacles on the ramp. The speed was measured at mesh nodes which are spaced at intervals of 15 cm along the length of the riverbed and of 10 cm across the cross section. Maps of the spatial distribution of the flow velocity were drafted based on the results obtained, from which maximum and minimum speeds, stream/current distribution and a rest zone for

  1. Organochlorine and trace element contamination in wintering and migrating diving ducks in the southern Great Lakes, USA, since the zebra mussel invasion

    Science.gov (United States)

    Custer, Christine M.; Custer, T.W.

    2000-01-01

    Because of the potential for increased trophic transfer of contaminants by zebra mussels (Dreissena sp.) to higher trophic levels, we collected four species of waterfowl (n = 65 ducks) from four locations in Lake Erie, Lake St. Clair, and Lake Michigan, USA, between 1991 and 1993 for organochlorine contaminant and trace element analyses. Geometric mean concentrations of total polychlorinated biphenyls (PCBs) and p,pa??-dichlorodiphenyldichloroethylene (DDE) were 1.35 and 0.15 I?g/g wet weight in lesser scaup (Aythya affinis) carcasses and were below known effect levels. Total PCBs in 80% of carcasses, however, were above the U.S. Food and Drug Administration's threshold of 3.0 I?g/g lipid weight for consumption of poultry. With the exception of selenium, trace elements were also at background or no-effect levels. Selenium concentrations in livers of 95% of lesser scaup, 90% of bufflehead (Bucephala albeola), and 72% of common goldeneye (Bucephala clangula) were in the elevated (>10 I?g/g dry wt) or potentially harmful range (>33 I?g/g dry wt). The effects of these high selenium concentrations are unknown but should be investigated further based on reproductive effects observed in field and laboratory studies of dabbling ducks and because lesser scaup populations are declining. Concentrations of total PCBs in dreissenid mussels in western Lake Erie were 10 times higher than in the upper Mississippi River but were similar to concentrations in other industrialized rivers in Europe and the United States. Metal concentrations were similar to other industrialized sites where zebra mussels have been sampled.

  2. Assessment of potential risk of environmental radioactive contamination in northern Europe from terrestrial nuclear units in north-west Russia

    International Nuclear Information System (INIS)

    Lisovsky, I.; Baklanov, A.; Jacovlev, V.; Prutskov, V.; Bergman, R.

    1999-05-01

    This Technical Report, being part of the INTAS project 96-1802, constitutes a comprehensive presentation - covering basic results from separate contributions as specified below - of work performed during the first period (February 1998- February 1999). The aim of the INTAS project 96-1802: 'Assessment of potential risk of environmental radioactive contamination in northern Europe from terrestrial nuclear units in north-west Russia' is to assess the potential risk of environmental radioactive contamination from nuclear units in north-west Russia and resulting impacts on population and terrestrial ecosystems in the north. The work focuses mainly on airborne radioactive contamination, but some case studies also deal with accidental leakage from terrestrial nuclear sites to soil and coastal waters. The present material comprises in more detail the contributions from participants no.4 and no.5 based on the four internal reports referred to below: (1) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in north-west Russia: 'Determination of the list of typical sources of danger emergency radioactive releases in an environment in connection with military activity in the North of Russia.' Technical report no.1 of the team no.5. St.-Petersburg State Technical University, St.-Petersburg. July 1998. 43 p.; (2) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in North-west Russia: 'Analysis and description of source-term characteristics for accident linked with airborne radioactive releases from Kola Nuclear Power Plant. Establishing a network facility at INEP for communication among the INTAS Project participants.' Technical report no.1 of the team no.4. Kola Science Centre, Apatity. August 1998. 56 p.; (3) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in

  3. Assessment of potential risk of environmental radioactive contamination in northern Europe from terrestrial nuclear units in north-west Russia

    Energy Technology Data Exchange (ETDEWEB)

    Lisovsky, I. [St. Petersburg State Technical Univ. (Russian Federation); Baklanov, A. [Inst. of the Northern Ecology Problems (INEP) (Russian Federation); Jacovlev, V. [St. Petersburg State Technical Univ. (Russian Federation); Prutskov, V. [Ministry of Defence (Russian Federation). First Central Research Inst. of Naval Shipbuilding; Tarasov, I. [Ministry of Defence (Russian Federation). 23 State Marine Project Inst.; Blecher, A. [State Unitary Enterprise (Russian Federation). Research Inst. of Industrial and Marine Medicine; Zvonariev, B.; Kuchin, N.; Rubanov, S.; Sergeiev, I. [State Scientific Centre (Russian Federation). Central Research Inst. of A. Krylov; Morozov, S.; Koshkin, V.; Fedorenko, Yu.; Rigina, O. [Inst. of the Northern Ecology Problems (INEP) (Russian Federation); Bergman, R. [ed.] [Defence Research Establishment, Umeaa (Sweden). Div. of NBC Defence

    1999-05-01

    This Technical Report, being part of the INTAS project 96-1802, constitutes a comprehensive presentation - covering basic results from separate contributions as specified below - of work performed during the first period (February 1998- February 1999). The aim of the INTAS project 96-1802: `Assessment of potential risk of environmental radioactive contamination in northern Europe from terrestrial nuclear units in north-west Russia` is to assess the potential risk of environmental radioactive contamination from nuclear units in north-west Russia and resulting impacts on population and terrestrial ecosystems in the north. The work focuses mainly on airborne radioactive contamination, but some case studies also deal with accidental leakage from terrestrial nuclear sites to soil and coastal waters. The present material comprises in more detail the contributions from participants no.4 and no.5 based on the four internal reports referred to below: (1) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in north-west Russia: `Determination of the list of typical sources of danger emergency radioactive releases in an environment in connection with military activity in the North of Russia.` Technical report no.1 of the team no.5. St.-Petersburg State Technical University, St.-Petersburg. July 1998. 43 p.; (2) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in North-west Russia: `Analysis and description of source-term characteristics for accident linked with airborne radioactive releases from Kola Nuclear Power Plant. Establishing a network facility at INEP for communication among the INTAS Project participants.` Technical report no.1 of the team no.4. Kola Science Centre, Apatity. August 1998. 56 p.; (3) Assessment of potential risk of environmental radioactive contamination in Northern Europe from terrestrial nuclear units in

  4. THE WEATHERING OF A SULFIDE OREBODY: SPECIATION AND FATE OF SOME POTENTIAL CONTAMINANTS

    Energy Technology Data Exchange (ETDEWEB)

    Courtin-Nomade, Alexandra; Grosbois, Cecile; Marcus, Matthew A.; Fakra, Sirine C.; Beny, Jean Michel; Foster, Andrea L.

    2010-07-16

    trace element distribution and relative abundance of the unweathered sulfides, this orebody still represents a significant reservoir of potential contaminants for the watershed, especially in the non-mining site, as a much greater proportion of sulfides is left to react and because of the lower porosity in this site.

  5. Potential of Sunflower (Helianthus annuus L.) for Phytoremediation of Soils Contaminated with Heavy Metals

    OpenAIRE

    Violina R. Angelova; Mariana N. Perifanova-Nemska; Galina P. Uzunova; Krasimir I. Ivanov; Huu Q. Lee

    2016-01-01

    A field study was conducted to evaluate the efficacy of the sunflower (Helianthus annuus L.) for phytoremediation of contaminated soils. The experiment was performed on an agricultural field contaminated by the Non-Ferrous-Metal Works near Plovdiv, Bulgaria. Field experiments with a randomized, complete block design with five treatments (control, compost amendments added at 20 and 40 t/daa, and vemicompost amendments added at 20 and 40 t/daa) were carried out. The accumulation of heavy metals...

  6. Phytoextractor Potential of Cultivated Species in Industrial Area Contaminated by Lead

    Directory of Open Access Journals (Sweden)

    Silvânia Maria de Souza Gomes Nascimento

    Full Text Available ABSTRACT: High growth rate is one of the criteria used for the selection of species to be used in metal phytoextraction programs. This study was carried out to characterize the growth characteristics of sunflower (Helianthus annuus L., castor bean (Ricinus communis L., corn (Zea mays L, and vetiver [Vetiveria zizanioides (L. Nash] grown on a soil contaminated with lead (Pb, with and without pH correction, to improve agronomic practices regarding phytoremediation programs. The experiment was designed as a randomized block with four replications; treatments were arranged in a split-plot arrangement, with the main plot representing the species (sunflower, castor bean, corn, and vetiver, with or without pH correction and soil fertilization, and the split-plot representing harvest periods (60, 90, and 120 days after planting. After variance analysis and mean comparison analysis of the data by the Tukey test (p≤0.05, a significant effect was observed from soil pH correction for vetiver in all of the growth variables evaluated, except for the leaf area index at 120 days after planting (DAP. Castor bean and sunflower plants in soil with high acidity conditions, without pH correction (pH˂4.0, were affected by soil Pb levels. Corn plants benefited from soil pH correction and had improved results for the plant height, diameter, and leaf area variables at 60 and 90 DAP, as well as leaf area index at 60 DAP. There was no increase in these variables between the harvest periods evaluated. Regarding phytoextraction potential, corn and vetiver had the highest Pb translocation to the plant shoots at 90 DAP and were therefore considered the most suitable species for phytoremediation of the area under study. Overall, liming was essential for improving species biomass production for all the species studied in soils with high Pb availability in solution.

  7. Coliform Contamination of Peri-urban Grown Vegetables and Potential Public Health Risks: Evidence from Kumasi, Ghana.

    Science.gov (United States)

    Abass, Kabila; Ganle, John Kuumuori; Adaborna, Eric

    2016-04-01

    Peri-urban vegetable farming in Ghana is an important livelihood activity for an increasing number of people. However, increasing quality and public health concerns have been raised, partly because freshwater availability for irrigation purposes is a major constraint. This paper investigated on-farm vegetable contamination and potential health risks using samples of lettuce, spring onions and cabbage randomly selected from 18 vegetable farms in peri-urban Kumasi, Ghana. Vegetable samples were tested for total coliform, fecal coliform, Escherichia coli and Salmonella spp. bacteria contamination using the Most Probable Number method. Results show high contamination levels of total and fecal coliforms, and Escherichia coli bacteria in all 18 vegetable samples. The mean total coliform/100 ml concentration for spring onions, lettuce and cabbage were 9.15 × 10(9), 4.7 × 10(7) and 8.3 × 10(7) respectively. The mean fecal coliform concentration for spring onions, lettuce and cabbage were also 1.5 × 10(8), 4.15 × 10(7) and 2.15 × 10(7) respectively, while the mean Escherichia coli bacteria contamination for spring onions, lettuce and cabbage were 1.4 × 10(8), 2.2 × 10(7) and 3.2 × 10(7) respectively. The level of total coliform, fecal coliform and Escherichia coli bacteria contamination in all the vegetable samples however declined as the distance between the main water source (Wiwi River) and farms increases. Nonetheless, all contamination levels were well above acceptable standards, and could therefore pose serious public health risks to consumers. Increased education and supervision of farmers, as well as public health and food hygiene education of consumers, are critical to reducing on-farm vegetable contamination and the health risks associated with consumption of such vegetables.

  8. Evaluation and communication of potential risk of radionuclide contamination of foods after Fukushima nuclear power plant accident

    International Nuclear Information System (INIS)

    Sekizawa, Jun; Nakamura, Yumiko

    2011-01-01

    A large scale nuclear power plant accident happened after the great earthquake with a huge tsunami in the Eastern part of Japan in March 2011. Potential risk from radionuclide contamination in foods after the nuclear power plant accident was estimated using data of radiological food contamination from the Ministry of Health, Labour and Welfare. Data analyzed by combining nuclide, food, level of radiation detection, period, age-classified population, were compared to provisional index levels of radionuclides, and existing contamination levels in food by natural radioactive potassium. Health risk was shown to be very low or negligible considering presence of background radiological exposure from foods and the environment. Appropriate explanation of risk to various stakeholders of the society is imperative and results of trials were reported. (author)

  9. GABAergic anxiolytic drug in water increases migration behaviour in salmon

    Science.gov (United States)

    Hellström, Gustav; Klaminder, Jonatan; Finn, Fia; Persson, Lo; Alanärä, Anders; Jonsson, Micael; Fick, Jerker; Brodin, Tomas

    2016-12-01

    Migration is an important life-history event in a wide range of taxa, yet many migrations are influenced by anthropogenic change. Although migration dynamics are extensively studied, the potential effects of environmental contaminants on migratory physiology are poorly understood. In this study we show that an anxiolytic drug in water can promote downward migratory behaviour of Atlantic salmon (Salmo salar) in both laboratory setting and in a natural river tributary. Exposing salmon smolt to a dilute concentration of a GABAA receptor agonist (oxazepam) increased migration intensity compared with untreated smolt. These results implicate that salmon migration may be affected by human-induced changes in water chemical properties, such as acidification and pharmaceutical residues in wastewater effluent, via alterations in the GABAA receptor function.

  10. Environmental surveillance of commonly-grown vegetables for investigating potential lead and chromium contamination intensification in Bangladesh.

    Science.gov (United States)

    Hossain, A M M Maruf; Islam, M Shahidul; Mamun, M Mustafa; Al-Jonaed, H M; Imran, M; Rahman, M Hasibur; Kazi, M Azizul Islam; Elahi, Syed Fazle

    2016-01-01

    With regard to previously reported Lead (Pb) and Chromium (Cr) contamination in egg, a semi-quantitative assessment of the general environment of Bangladesh is carried out through nation-wide sampling of commonly grown and consumed vegetables. Five vegetables, namely, White Potato ( Solanum tuberosum ), Green Cabbage ( Brassica oleracea capitata var. alba L.), Red Spinach ( Amaranthus dubius ), White Radish ( Raphanus sativus var. longipinnatus ), and Green Bean ( Phaseolus vulgaris ) were selected for sampling from all 64 Districts of the country as per their availability during the sampling season. This results in a collection of 292 samples. Due to the necessity of incorporating a wide spectrum of vegetable types (e.g. tuber, brassica, leafy, root, and fruiting vegetables) as well as the need for including the geographic expanse of the whole country, replicates were not accommodated in the study, hence, the study being semi-quantitative in nature. The results do not substantiate evidence of public health risk due to Cr yet, with only 0.69 % of the samples found contaminated with Cr. Pb contamination (concentrations above a health-based guidance value) is found in 29.47 % of the samples; and together with the insight of such contamination likely being non-point origin, communicates on potential public health risk due to Pb as residual effects of extensive ambient atmospheric Pb pollution in recent history of the country. For the purpose of comparison, Cadmium (Cd) contents of the samples are also analyzed. Although there is no extensive Cd pollution history/source in the country, the likely point-source nature of Cd contamination found in 17.83 % of the samples indicates the scope of managing any existing contamination source by directing efforts into the potential point-sources.

  11. Metal and Isotope Analysis of Bird Feathers in a Contaminated Estuary Reveals Bioaccumulation, Biomagnification, and Potential Toxic Effects.

    Science.gov (United States)

    Einoder, L D; MacLeod, C K; Coughanowr, C

    2018-07-01

    The Derwent estuary, in south east Tasmania, is highly contaminated with heavy metals, mainly due to past industrial pollution. This study sought to determine the extent of contamination, bioaccumulation, and biomagnification in the resident bird community and therefore to infer the potential for adverse effects in birds. Thirteen metals were measured from breast feathers (n = 51 individuals) of eight sympatric species of aquatic bird. Stable carbon (δ 13 C) and nitrogen (δ 15 N) isotopes were used to identify dietary sources of contaminants, trophic level, and potential biomagnification through food chains. Generalised linear models revealed that metal burdens were often poorly correlated with δ 13 C, indicating their uptake from a range of freshwater, brackish, and marine carbon sources-not surprising due to widespread contamination across the tidal estuary. Feather mercury increased significantly with trophic level (inferred from δ 15 N). White-bellied Sea-eagle Haliaeetus leucogaster samples contained 240 times more mercury than feral Goose Anser cygnoides. Feather arsenic and copper concentrations were significantly higher in birds feeding lower in the food chain. For several piscivorous species, both chick and adults were sampled revealing significantly higher feather mercury, zinc, and selenium in adults. Feathers from birds found dead along the banks of the estuary had significantly higher lead loads than from live birds, and numerous individuals had levels of mercury, zinc, and lead above toxic thresholds reported in other studies. These results highlight the need to include biota from higher trophic levels in contaminant monitoring programs to understand fully the fate and broader implications of contaminants in the environment.

  12. Molecular identification and potential of an isolate of white rot fungi in bioremediation of petroleum contaminated soils

    Directory of Open Access Journals (Sweden)

    Maryam Mohammadi-sichani

    2017-06-01

    Full Text Available Introduction:Elimination or reduction of petroleum hydrocarbons from natural resources such as water and soil is a serious problem of countries, particularly oil-rich countries of the world. Using white rotting fungi compost for bioremediation of soils contaminated by petroleum hydrocarbons is effective. The aim of this study is molecular identification and potential of anisolate of white rot fungi in bioremediation of petroleum contaminated soils. Materials and methods: Spent compost of white rotting fungi was inoculated with petroleum contaminated soil into 3%, 5% and 10% (w/w. Treatments were incubated at 25-23 °C for 3 months. Reduction of petroleum hydrocarbons in treated soil was determined by gas chromatography. Ecotoxicity of soil was evaluated by seed germination test. Results: Based on the genome sequence of 18s rRNA, it is revealed that this isolate is Ganoderma lucidum and this isolate is deposited as accession KX525204 in the Gene Bank database. Reduction of petroleum hydrocarbons in soil treated with compost (3, 5 and 10% ranged from 42% to 71%. The germination index (% in ecotoxicity tests ranged from 20.8% to 70.8%. Gas chromatography results also showed a decrease in soil Hydrocarbons compounds. Discussion and conclusion: The compost of Ganoderma lucidum, a white rot fungus, has a potential ability to remove petroleum hydrocarbons in contaminated soil. Removal of hydrocarbons was increased with increase in compost mixed with contaminated soil. Petroleum contaminated soil amended with spent compost of G.lucidum 10% during three months is appropriate to remove this pollutant.

  13. The water-soluble fraction of potentially toxic elements in contaminated soils: relationships between ecotoxicity, solubility and geochemical reactivity.

    Science.gov (United States)

    Rocha, L; Rodrigues, S M; Lopes, I; Soares, A M V M; Duarte, A C; Pereira, E

    2011-09-01

    To better understand the impacts posed by soil contamination to aquatic ecosystems it is crucial to characterise the links between ecotoxicity, chemical availability and geochemical reactivity of potentially toxic elements (PTE's) in soils. We evaluated the adverse effects of water extracts obtained from soils contaminated by chemical industry and mining, using a test battery including organisms from different trophic levels (bacteria, algae and daphnids). These tests provided a quick assessment of the ecotoxicity of soils with respect to possible adverse effects on aquatic organisms although the ecotoxicological responses could be related to the solubility of PTE's only to a limited extent. The analysis of results of bioassays together with the chemical characterisation of water extracts provided additional relevant insight into the role of conductivity, pH, Al, Fe, and Mn of soil extracts on toxicity to organisms. Furthermore, an important conclusion of this study was that the toxicity of extracts to the aquatic organisms could also be related to the soil properties (pH, Org C and Fe(ox)) and to the reactivity of PTE's in soils which in fact control the soluble fraction of the contaminants. The combined assessment of ecotoxicity in water fractions, solubility and geochemical reactivity of PTE's in soils provided a more comprehensive understanding of the bioavailability of inorganic contaminants than ecotoxicological or chemical studies alone and can therefore be most useful for environmental risks assessment of contaminated soils. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Effect of negative air ions on the potential for bacterial contamination of plastic medical equipment.

    Science.gov (United States)

    Shepherd, Simon J; Beggs, Clive B; Smith, Caroline F; Kerr, Kevin G; Noakes, Catherine J; Sleigh, P Andrew

    2010-04-12

    presence of the ionizer. The findings of the study suggest that the action of negative air ionizers significantly alters the electrostatic landscape of the clinical environment, and that this has the potential to cause any Acinetobacter-bearing particles in the air to be strongly repelled from some plastic surfaces and attracted to others. In so doing, this may prevent critical items of equipment from becoming contaminated with the bacterium.

  15. Effect of negative air ions on the potential for bacterial contamination of plastic medical equipment

    Directory of Open Access Journals (Sweden)

    Kerr Kevin G

    2010-04-01

    acrylonitrile, did however develop a positive charge in the presence of the ionizer. Conclusion The findings of the study suggest that the action of negative air ionizers significantly alters the electrostatic landscape of the clinical environment, and that this has the potential to cause any Acinetobacter-bearing particles in the air to be strongly repelled from some plastic surfaces and attracted to others. In so doing, this may prevent critical items of equipment from becoming contaminated with the bacterium.

  16. Resistivity and self-potential tomography applied to groundwater remediation and contaminant plumes: Sandbox and field experiments

    Science.gov (United States)

    Mao, D.; Revil, A.; Hort, R. D.; Munakata-Marr, J.; Atekwana, E. A.; Kulessa, B.

    2015-11-01

    Geophysical methods can be used to remotely characterize contaminated sites and monitor in situ enhanced remediation processes. We have conducted one sandbox experiment and one contaminated field investigation to show the robustness of electrical resistivity tomography and self-potential (SP) tomography for these applications. In the sandbox experiment, we injected permanganate in a trichloroethylene (TCE)-contaminated environment under a constant hydraulic gradient. Inverted resistivity tomograms are able to track the evolution of the permanganate plume in agreement with visual observations made on the side of the tank. Self-potential measurements were also performed at the surface of the sandbox using non-polarizing Ag-AgCl electrodes. These data were inverted to obtain the source density distribution with and without the resistivity information. A compact horizontal dipole source located at the front of the plume was obtained from the inversion of these self-potential data. This current dipole may be related to the redox reaction occurring between TCE and permanganate and the strong concentration gradient at the front of the plume. We demonstrate that time-lapse self-potential signals can be used to track the kinetics of an advecting oxidizer plume with acceptable accuracy and, if needed, in real time, but are unable to completely resolve the shape of the plume. In the field investigation, a 3D resistivity tomography is used to characterize an organic contaminant plume (resistive domain) and an overlying zone of solid waste materials (conductive domain). After removing the influence of the streaming potential, the identified source current density had a magnitude of 0.5 A m-2. The strong source current density may be attributed to charge movement between the neighboring zones that encourage abiotic and microbially enhanced reduction and oxidation reactions. In both cases, the self-potential source current density is located in the area of strong resistivity

  17. Potential of near-infrared hyperspectral reflectance imaging for screening of farm feed contamination

    Science.gov (United States)

    Wang, Wenbo; Paliwal, Jitendra

    2005-09-01

    With the outbreak of Bovine Spongiform Encephalopathy (BSE) (commonly known as mad cow disease) in 1987 in the United Kingdom and a recent case discovered in Alberta, more and more emphasis is placed on food and farm feed quality and safety issues internationally. The disease is believed to be spread through farm feed contamination by animal byproducts in the form of meat-and-bone-meal (MBM). The paper reviewed the available techniques necessary to the enforcement of legislation concerning the feed safety issues. The standard microscopy method, although highly sensitive, is laborious and costly. A method to routinely screen farm feed contamination certainly helps to reduce the complexity of safety inspection. A hyperspectral imaging system working in the near-infrared wavelength region of 1100-1600 nm was used to study the possibility of detection of ground broiler feed contamination by ground pork. Hyperspectral images of raw broiler feed, ground broiler feed, ground pork, and contaminated feed samples were acquired. Raw broiler feed samples were found to possess comparatively large spectral variations due to light scattering effect. Ground feed adulterated with 1%, 3%, 5%, and 10% of ground pork was tested to identify feed contamination. Discriminant analysis using Mahalanobis distance showed that the model trained using pure ground feed samples and pure ground pork samples resulted in 100% false negative errors for all test replicates of contaminated samples. A discriminant model trained with pure ground feed samples and 10% contamination level samples resulted in 12.5% false positive error and 0% false negative error.

  18. Potential of different AM fungi (native from As-contaminated and uncontaminated soils) for supporting Leucaena leucocephala growth in As-contaminated soil.

    Science.gov (United States)

    Schneider, Jerusa; Bundschuh, Jochen; Rangel, Wesley de Melo; Guilherme, Luiz Roberto Guimarães

    2017-05-01

    Arbuscular mycorrhizal (AM) fungi inoculation is considered a potential biotechnological tool for an eco-friendly remediation of hazardous contaminants. However, the mechanisms explaining how AM fungi attenuate the phytotoxicity of metal(oid)s, in particular arsenic (As), are still not fully understood. The influence of As on plant growth and the antioxidant system was studied in Leucaena leucocephala plants inoculated with different isolates of AM fungi and exposed to increasing concentrations of As (0, 35, and 75 mg dm -3 ) in a Typic Quartzipsamment soil. The study was conducted under greenhouse conditions using isolates of AM fungi selected from uncontaminated soils (Acaulospora morrowiae, Rhizophagus clarus, Gigaspora albida; and a mixed inoculum derived from combining these isolates, named AMF Mix) as well as a mix of three isolates from an As-contaminated soil (A. morrowiae, R. clarus, and Paraglomus occultum). After 21 weeks, the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) were determined in the shoots in addition to measuring plant height and mineral contents. In general, AM fungi have shown multiple beneficial effects on L. leucocephala growth. Although the activity of most of the stress-related enzymes increased in plants associated with AM fungi, the percentage increase caused by adding As to the soil was even greater for non-mycorrhizal plants when compared to AM-fungi inoculated ones, which highlights the phytoprotective effect provided by the AM symbiosis. The highest P/As ratio observed in AM-fungi plants, compared to non-mycorrhizal ones, can be considered a good indicator that the AM fungi alter the pattern of As(V) uptake from As-contaminated soil. Our results underline the role of AM fungi in increasing the tolerance of L. leucocephala to As stress and emphasize the potential of the symbiosis L. leucocephala-R. clarus for As-phytostabilization at moderately As-contaminated

  19. A 28,000 Years Old Cro-Magnon mtDNA Sequence Differs from All Potentially Contaminating Modern Sequences

    Science.gov (United States)

    Caramelli, David; Milani, Lucio; Vai, Stefania; Modi, Alessandra; Pecchioli, Elena; Girardi, Matteo; Pilli, Elena; Lari, Martina; Lippi, Barbara; Ronchitelli, Annamaria; Mallegni, Francesco; Casoli, Antonella; Bertorelle, Giorgio; Barbujani, Guido

    2008-01-01

    Background DNA sequences from ancient speciments may in fact result from undetected contamination of the ancient specimens by modern DNA, and the problem is particularly challenging in studies of human fossils. Doubts on the authenticity of the available sequences have so far hampered genetic comparisons between anatomically archaic (Neandertal) and early modern (Cro-Magnoid) Europeans. Methodology/Principal Findings We typed the mitochondrial DNA (mtDNA) hypervariable region I in a 28,000 years old Cro-Magnoid individual from the Paglicci cave, in Italy (Paglicci 23) and in all the people who had contact with the sample since its discovery in 2003. The Paglicci 23 sequence, determined through the analysis of 152 clones, is the Cambridge reference sequence, and cannot possibly reflect contamination because it differs from all potentially contaminating modern sequences. Conclusions/Significance: The Paglicci 23 individual carried a mtDNA sequence that is still common in Europe, and which radically differs from those of the almost contemporary Neandertals, demonstrating a genealogical continuity across 28,000 years, from Cro-Magnoid to modern Europeans. Because all potential sources of modern DNA contamination are known, the Paglicci 23 sample will offer a unique opportunity to get insight for the first time into the nuclear genes of early modern Europeans. PMID:18628960

  20. Ranking harbours in the maritime provinces of Canada for potential to contaminate American lobster (Homarus americanus) with polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Prouse, N.J.

    1994-01-01

    Polycyclic aromatic hydrocarbons (PAHs) comprise a suite of contaminants that enter the marine environment through a variety of natural and anthropogenic sources. PAHs, including carcinogenic compounds, bioaccumulate in the tissues of exposed American lobsters (Homarus americanus). High PAH concentrations in lobster tissues necessitated the closure of the lobster fishery in the South Arm of Sydney Harbour, Nova Scotia, in 1982. A study was conducted to assess harbors in Nova Scotia, New Brunswick, and Prince Edward Island to determine if there might be a reason for concern about PAH contamination of lobsters. Adjacent commercial and industrial activity, harbor uses, the surrounding population, and PAH point sources were evaluated for each harbor selected for study. Areas of lobster fishing and the number of permanent lobster holding facilities within each harbor were also determined. Harbors were then ranked according to their potential for PAH contamination. Point sources for PAHs within these harbors included petroleum and coal products plants, oil refineries, chemical plants, coal-fired generating stations, and fuel combustion in land vehicles and ships. After Sydney, the harbors with the highest potential for PAH contamination were determined to be Halifax, Saint John, Pictou, and Port Hawkesbury Ship Harbour. 60 refs., 15 figs., 7 tabs.

  1. A 28,000 years old Cro-Magnon mtDNA sequence differs from all potentially contaminating modern sequences.

    Directory of Open Access Journals (Sweden)

    David Caramelli

    Full Text Available BACKGROUND: DNA sequences from ancient specimens may in fact result from undetected contamination of the ancient specimens by modern DNA, and the problem is particularly challenging in studies of human fossils. Doubts on the authenticity of the available sequences have so far hampered genetic comparisons between anatomically archaic (Neandertal and early modern (Cro-Magnoid Europeans. METHODOLOGY/PRINCIPAL FINDINGS: We typed the mitochondrial DNA (mtDNA hypervariable region I in a 28,000 years old Cro-Magnoid individual from the Paglicci cave, in Italy (Paglicci 23 and in all the people who had contact with the sample since its discovery in 2003. The Paglicci 23 sequence, determined through the analysis of 152 clones, is the Cambridge reference sequence, and cannot possibly reflect contamination because it differs from all potentially contaminating modern sequences. CONCLUSIONS/SIGNIFICANCE: The Paglicci 23 individual carried a mtDNA sequence that is still common in Europe, and which radically differs from those of the almost contemporary Neandertals, demonstrating a genealogical continuity across 28,000 years, from Cro-Magnoid to modern Europeans. Because all potential sources of modern DNA contamination are known, the Paglicci 23 sample will offer a unique opportunity to get insight for the first time into the nuclear genes of early modern Europeans.

  2. Status of metal levels and their potential sources of contamination in Southeast Asian rivers.

    Science.gov (United States)

    Chanpiwat, Penradee; Sthiannopkao, Suthipong

    2014-01-01

    To assess the concentration and status of metal contaminants in four major Southeast Asian river systems, water were collected from the Tonle Sap-Bassac Rivers (Cambodia), Citarum River (Indonesia), lower Chao Phraya River (Thailand), and Saigon River (Vietnam) in both dry and wet seasons. The target elements were Be, Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Ba, Tl, and Pb and the concentrations exceeded the background metal concentrations by 1- to 88-fold. This distinctly indicates enrichment by human urban area activities. The results of a normalization technique used to distinguish natural from enriched metal concentrations confirmed contamination by Al, Cd, Co, Mn, Ni, Pb, and Zn. Cluster analysis revealed the probable source of metals contamination in most sampling sites on all rivers studied to be anthropogenic, including industrial, commercial, and residential activities. Stable lead isotopes analyses applied to track the sources and pathways of anthropogenic lead furthermore confirmed that anthropogenic sources of metal contaminated these rivers. Discharges of wastewater from both industrial and household activities were major contributors of Pb into the rivers. Non-point sources, especially road runoff and street dust, also contributed contamination from Pb and other metals.

  3. Endometrial Cancer Side-Population Cells Show Prominent Migration and Have a Potential to Differentiate into the Mesenchymal Cell Lineage

    Science.gov (United States)

    Kato, Kiyoko; Takao, Tomoka; Kuboyama, Ayumi; Tanaka, Yoshihiro; Ohgami, Tatsuhiro; Yamaguchi, Shinichiro; Adachi, Sawako; Yoneda, Tomoko; Ueoka, Yousuke; Kato, Keiji; Hayashi, Shinichi; Asanoma, Kazuo; Wake, Norio

    2010-01-01

    Cancer stem-like cell subpopulations, referred to as “side-population” (SP) cells, have been identified in several tumors based on their ability to efflux the fluorescent dye Hoechst 33342. Although SP cells have been identified in the normal human endometrium and endometrial cancer, little is known about their characteristics. In this study, we isolated and characterized the SP cells in human endometrial cancer cells and in rat endometrial cells expressing oncogenic human K-Ras protein. These SP cells showed i) reduction in the expression levels of differentiation markers; ii) long-term proliferative capacity of the cell cultures; iii) self-renewal capacity in vitro; iv) enhancement of migration, lamellipodia, and, uropodia formation; and v) enhanced tumorigenicity. In nude mice, SP cells formed large, invasive tumors, which were composed of both tumor cells and stromal-like cells with enriched extracellular matrix. The expression levels of vimentin, α-smooth muscle actin, and collagen III were enhanced in SP tumors compared with the levels in non-SP tumors. In addition, analysis of microdissected samples and fluorescence in situ hybridization of Hec1-SP-tumors showed that the stromal-like cells with enriched extracellular matrix contained human DNA, confirming that the stromal-like cells were derived from the inoculated cells. Moreober, in a Matrigel assay, SP cells differentiated into α-smooth muscle actin-expressing cells. These findings demonstrate that SP cells have cancer stem-like cell features, including the potential to differentiate into the mesenchymal cell lineage. PMID:20008133

  4. Self-potential monitoring of a crude oil contaminated site (Trecate, Italy): first results of the modelling.

    Science.gov (United States)

    Giampaolo, V.; Rizzo, E.; Titov, K.; Maineult, A.; Lapenna, V.

    2012-04-01

    The contamination of soils and groundwater by hydrocarbon, due to blow out, leakage from tank or pipe and oil spill, is a heavy environmental problem because infiltrated oil can persist in the ground for a long time. The existing methods used for the remediation of these contaminated sites are invasive, time consuming and expensive. Therefore, in the last years, there was a growing interest in the use of geophysical methods for environmental monitoring (Atekwana et al., 2000; Chambers et al., 2004; Song et al., 2005; French et al., 2009). A particular attention is given to the self-potential (SP) method because SP is sensitive to the contaminant chemistry and redox processes generated by bacteria during the biodegradation (Atekwana et al., 2004; Naudet and Revil, 2005; Revil et al., 2010). Here we show the results of SP investigations carried out at Trecate site (Italy). This site was affected by a crude oil contamination from a well blowout in 1994. Four SP surveys (October 2009, March 2010, October 2010, and March 2011) were conducted at the site, both in the contaminated and uncontaminated regions. Significant changes are observed between SP data collected at different times. In particular, we found mostly negative electrical potential in October surveys and positive electrical potential in March surveys. The SP distributions can be interpreted as the superposition of many components, including a horizontal water-flow in the saturated shallow aquifer toward South-East, the infiltration movement of water in the unsaturated zone and, possibly, the oxidation-reduction phenomena due to bacterial activity. As the groundwater flow usually produces SP linear trends, the data were detrended by linear regression, taking into account the measured piezometric heads in the aquifer. The detrended SP data show that the SP distribution within the contaminated zone is generally bipolar in October: the southern part of the contaminated area is characterized by negative values

  5. Phytoremediation potential of weeds in heavy metal contaminated soils of the Bassa Industrial Zone of Douala, Cameroon.

    Science.gov (United States)

    Lum, A Fontem; Ngwa, E S A; Chikoye, D; Suh, C E

    2014-01-01

    Phytoremediation is a promising option for reclaiming soils contaminated with toxic metals, using plants with high potentials for extraction, stabilization and hyperaccumulation. This study was conducted in Cameroon, at the Bassa Industrial Zone of Douala in 2011, to assess the total content of 19 heavy metals and 5 other elements in soils and phytoremediation potential of 12 weeds. Partial extraction was carried out in soil, plant root and shoot samples. Phytoremediation potential was evaluated in terms of the Biological Concentration Factor, Translocation Factor and Biological Accumulation Coefficient. The detectable content of the heavy metals in soils was Cu:70-179, Pb:8-130, Zn:200-971, Ni:74-296, Co:31-90, Mn:1983-4139, V:165-383, Cr:42-1054, Ba:26-239, Sc:21-56, Al:6.11-9.84, Th:7-22, Sr:30-190, La:52-115, Zr:111-341, Y:10-49, Nb:90-172 in mg kg(-1), and Ti:2.73-4.09 and Fe:12-16.24 in wt%. The contamination index revealed that the soils were slightly to heavily contaminated while the geoaccumulation index showed that the soils ranged from unpolluted to highly polluted. The concentration of heavy metals was ranked as Zn > Ni > Cu > V > Mn > Sc > Co > Pb and Cr in the roots and Mn > Zn > Ni > Cu > Sc > Co > V > Pb > Cr > Fe in the shoots. Dissotis rotundifolia and Kyllinga erecta had phytoextraction potentials for Pb and Paspalum orbicularefor Fe. Eleusine indica and K. erecta had phytostabilisation potential for soils contaminated with Cu and Pb, respectively.

  6. Potential of glycerol and soybean oil for bioremediation of weathered oily-sludge contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, T.C.F.; Franca, F.P. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica], E-mail: fpfranca@eq.ufrj.br; Oliveira, F.J.S. [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2012-04-15

    The bioremediation of petroleum-contaminated soil was investigated on laboratory scale. This work evaluated the effect of co-substrate addition in tropical climate soil highly contaminated with oily residue. Glycerol and soybean oil were used as auxiliary co-substrates for contaminant degradation. Three different concentrations of co-substrate were tested, and the experiments were carried out over 60 days. The following parameters were monitored: humidity, pH, total heterotrophic bacteria, total fungi, total petroleum hydrocarbons (TPH), and the concentrations of benzo[a]pyrene and chrysene. The soil supplementation with renewable co-substrates improved the efficiency of the biodegradation TPH, with removals of 85% and 83% for glycerol and soybean oil, respectively, compared to a 55% removal yielded by the biodegradation process without supplementation. The use of glycerol increased Chrysene and Benzo[a]pyrene biodegradation by 50%, while soybean oil supplementation increased their removal by 36%. (author)

  7. Occurrence and potential crop uptake of emerging contaminants and related compounds in an agricultural irrigation network.

    Science.gov (United States)

    Calderón-Preciado, Diana; Matamoros, Víctor; Bayona, Josep M

    2011-12-15

    Emerging contaminants have received much attention in recent years due to their presence in surface waters, but little attention has been paid to their occurrence in agricultural irrigation waters. This study investigated the occurrence of these compounds in an agricultural irrigation network in northeastern Spain and, for the first time, using two plant uptake models, estimated the concentration of selected micropollutants in crops. The concentration of micropollutants in agricultural irrigation waters ranged from 10 to 5130 ng L(-1) and exhibited some attenuation over the course of the irrigation network. Bromoform, chloroform, diclofenac, caffeine, ibuprofen, naproxen, methyl dihydrojasmonate, galaxolide, butylated hydroxytoluene, and butylated hydroxyanisole were the most abundant contaminants (>200 ng L(-1), on average). The estimated concentration of micropollutants in crops ranged from contaminants detected). Further studies are needed to determine the health implications that the presence of these compounds in fruit and vegetables may have for consumers. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Investigations on potential bacteria for the bioremediation treatment of environments contaminated with hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Lazar, I.; Voicu, A.; Dobrota, S.; Stefanescu, M. [Institute of Biology of Romanian Academy, Bucharest (Romania)] [and others

    1995-12-31

    In Romania after more than 135 years of oil production and processing, some severe environmental pollution problems have accumulated. In this context a joint research group from Institute of Biology Bucharest and S.C. Petrostar S.A. Ploiesti became involved in a research project on bioremediation of an environment contaminated with hydrocarbon waste. In the first stage of this project, investigations on microbial communities occurring in environments contaminated with oil were carried out. In the second stage, the hundreds of bacterial strains and populations isolated from soils, slops, and water sites contaminated with waste oil and water waste oil mix were submitted to a screening program, to select a naturally occurring mixed culture with a high ability to degrade hydrocarbons.

  9. Allee effect in polar bears: a potential consequence of polychlorinated biphenyl contamination.

    Science.gov (United States)

    Pavlova, Viola; Nabe-Nielsen, Jacob; Dietz, Rune; Sonne, Christian; Grimm, Volker

    2016-11-30

    Polar bears (Ursus maritimus) from East Greenland and Svalbard exhibited very high concentrations of polychlorinated biphenyls (PCBs) in the 1980s and 1990s. In Svalbard, slow population growth during that period was suspected to be linked to PCB contamination. In this case study, we explored how PCBs could have impacted polar bear population growth and/or male reproductive success in Svalbard during the mid-1990s by reducing the fertility of contaminated males. A dose-response relationship linking the effects of PCBs to male polar bear fertility was extrapolated from studies of the effects of PCBs on sperm quality in rodents. Based on this relationship, an individual-based model of bear interactions during the breeding season predicted fertilization success under alternative assumptions regarding male-male competition for females. Contamination reduced pregnancy rates by decreasing the availability of fertile males, thus triggering a mate-finding Allee effect, particularly when male-male competition for females was limited or when infertile males were able to compete with fertile males for females. Comparisons of our model predictions on age-dependent reproductive success of males with published empirical observations revealed that the low representation of 10-14-year-old males among breeding males documented in Svalbard in mid-1990s could have resulted from PCB contamination. We conclude that contamination-related male infertility may lead to a reduction in population growth via an Allee effect. The magnitude of the effect is largely dependent on the population-specific mating system. In eco-toxicological risk assessments, appropriate consideration should therefore be given to negative effects of contaminants on male fertility and male mating behaviour. © 2016 The Author(s).

  10. Technologies for remediating radioactively contaminated land

    International Nuclear Information System (INIS)

    Pearl, M.

    2000-01-01

    This paper gives an overview of technologies that can be used for the remediation of radioactively contaminated ground. There are a wide variety of techniques available -most have established track records for contaminated ground, though in general many are only just being adapted to use for radioactively contaminated ground. 1) Remediation techniques for radioactively contaminated ground involve either removal of the contamination and transfer to a controlled/contained facility such as the national LLW repository at Drigg, or 2) immobilization, solidification and stabilization of the contamination where the physical nature of the soil is changed, or an 'agent' is added to the soil, to reduce the migration of the contaminants, or 3) isolation and containment of the contaminated ground to reduce contaminant migration and control potential detrimental effects to human health. Where contamination has to be removed, ex situ and in situ techniques are available which minimize the waste requiring disposal to an LLW repository. These techniques include: 1) detector-based segregation 2) soil washing by particle separations 3) oil washing with chemical leaching agents 4) electro remediation 5) phyto remediation. Although many technologies are potentially applicable, their application to the remediation of a specific contaminated site is dependent on a number of factors and related to detailed site characterization studies, results from development trials and BPEO (best practicable environmental option) studies. Those factors considered of particular importance are: 1) the clean-up target 2) technical feasibility relative to the particular site, soil and contaminant characteristics, and time frame 3) site infrastructure arrangements and needs, the working life of the site and the duration of institutional care 4) long-term monitoring arrangements for slow remedial techniques or for immobilization and containment techniques 5) validation of the remediation 6) health and

  11. Cadmium (Cd) Localization in Tissues of Cotton (Gossypium hirsutum L.), and Its Phytoremediation Potential for Cd-Contaminated Soils.

    Science.gov (United States)

    Chen, Zhifan; Zhao, Ye; Fan, Lidong; Xing, Liteng; Yang, Yujie

    2015-12-01

    Phytoremediation using economically valuable, large biomass, non-edible plants is a promising method for metal-contaminated soils. This study investigated cotton's tolerance for Cd and remediation potential through analyzing Cd bioaccumulation and localization in plant organs under different soil Cd levels. Results showed cotton presents good tolerance when soil Cd concentration ≤20.26 mg kg(-1). Cotton had good Cd accumulation ability under low soil Cd levels (soil Cd, while roots and stems were the main compartments of Cd storage. Cd complexation to other organic constituents in root and stem cell sap could be a primary detoxifying strategy. Therefore, cotton is a potential candidate for phytoremediation of Cd-contaminated soils.

  12. Phytoremediation of heavy metal contaminated soil potential by woody plants on Tonglushan ancient copper spoil heap in China.

    Science.gov (United States)

    Kang, Wei; Bao, Jianguo; Zheng, Jin; Xu, Fen; Wang, Liuming

    2018-01-02

    Fast-growing metal-accumulating woody plants are considered potential candidates for phytoremediation of metals. Tonglushan mining, one of the biggest Cu production bases in China, presents an important source of the pollution of environment. The sample was collected at Tonglushan ancient copper spoil heap. The aims were to measure the content of heavy metal in the soil and woody plants and to elucidate the phytoremediation potential of the plants. The result showed that soil Cu, Cd and Pb were the main contamination, the mean contents of which were 3166.73 mg/kg, 3.66 mg/kg and 137.06 mg/kg respectively, which belonged to severe contamination. Fourteen species from 14 genera of 13 families were collected and investigated; except for Ligutrum lucidum, the other 13 woody plants species were newly recorded in this area. In addition, to assess the ability of metal accumulation of these trees, we proposed accumulation index. Data suggested that Platanus × acerilolia, Broussonetia papyrifera, Ligutrum lucidum, Viburnum awabuki, Firmiana simplex, Robina pseudoacacia, Melia azedarach and Osmanthus fragrans exhibited high accumulated capacity and strong tolerance to heavy metals. Therefore, Platanus × acerilolia and Broussonetia papyrifera can be planted in Pb contaminated areas; Viburnum awabuki, Firmiana simplex, Robina pseudoacacia and Melia azedarach are the suitable trees for Cd contaminated areas; Viburnum awabuki, Melia azedarach, Ligutrum lucidum, Firmiana simplex, Osmanthus fragrans and Robina pseudoacacia are appropriate to Cu, Pb and Cd multi-metal contaminated areas.

  13. Phytostabilization potential of two ecotypes of Vetiveria zizanioides in cadmium-contaminated soils: greenhouse and field experiments.

    Science.gov (United States)

    Phusantisampan, Theerawut; Meeinkuirt, Weeradej; Saengwilai, Patompong; Pichtel, John; Chaiyarat, Rattanawat

    2016-10-01

    Soil contamination by cadmium (Cd) poses a serious environmental and public health concern. Phytoremediation, i.e., the use of plants to remove contaminants from soil, has been proposed for treatment of Cd-contaminated ecosystems. In this study, we demonstrated the potential of Vetiveria zizanioides, commonly known as vetiver, to serve as an effective phytoremediation agent. Two ecotypes, i.e., India and Sri Lanka, were grown in greenhouse pots and in the field. Soils were amended with cow manure, pig manure, bat manure, and an organic fertilizer. Among all amendments, pig manure performed best in both greenhouse and field studies in terms of increasing total V. zizanioides biomass production in both ecotypes. In both greenhouse and in the field, tissue of the Sri Lanka ecotype had higher Cd concentrations than did the India ecotype. In the greenhouse, the presence of Cd did not affect total biomass production or root dry weight. The Sri Lanka ecotype had 2.7 times greater adventitious root numbers and 3.6 times greater Cd accumulation in roots than did the India ecotype. In the field study, the Sri Lanka ecotype offers potential as an excluder species, as it accumulated Cd primarily in roots, with translocation factor values 1 for all experiments except for the pig manure amendment. In addition, the highest Cd concentration in the Sri Lanka ecotype root (71.3 mg kg(-1)) was consistent with highest Cd uptake (10.4 mg plant(-1)) in the cow manure treatment. The India ecotype contained lower root Cd concentrations, and Cd accumulation was slightly higher in shoots compared to roots, with translocation factor (TF) values >1. The India ecotype was therefore not considered as an excluder in the Cd-contaminated soil. With the use of excluder species combined with application of organic amendments, soil contamination by Cd may be treated by alternative remediation methods such as phytostabilization.

  14. Organization A Comprehensive System Of Insurance Coverage In The Potential Chemical And Biological Contamination Zone In Regions

    Directory of Open Access Journals (Sweden)

    Nina Vladimirovna Zaytseva

    2014-12-01

    Full Text Available The article provides a scientific rationale for an integrated approach to the provision of insurance coverage in the potential chemical and biological contamination zone. The following modern forms of chemical safety in the Russian Federation were considered: state reserve’s system, target program financing, state social insurance. The separate issue tackles the obligatory civil liability insurance for owners of dangerous objects. For improvement of the existing insurance protection system against emergency situations, risks were analyzed (shared on exogenous and endogenous. Among the exogenous risks including natural and climatic conditions of a region, its geographical arrangement, economic specialization, the seismic and terrorist risks were chosen and approaches to its solution were suggested. In endogenous risks’ group, the special focus is on wear and tear and obsolescence of hazardous chemical and biological object’s fixed assets. In case of high risk of an incident, it is suggested to increase in extent of insurance protection through self-insurance, a mutual insurance in the form of the organization of societies of a mutual insurance or the self-regulating organizations, and also development of voluntary insurance of a civil liability, both the owner of hazardous object, and regions of the Russian Federation and municipalities. The model of insurance coverage in the potential chemical and biological contamination zone is based on a differentiated approach to the danger level of the area. A matrix of adequate forms and types of insurance (required for insurance coverage of the population in the potential chemical and biological contamination zone was constructed. Proposed health risk management toolkit in the potential chemical and biological contamination zone will allow to use financial resources for chemical and biological safety in the regions more efficiently.

  15. ENVIRONMENTAL CONTAMINANTS AND POTENTIAL HUMAN RISK ASSOCIATED WITH SELECTED BOTANICAL DIETARY SUPPLEMENTS

    Science.gov (United States)

    Botanical dietary supplements have a long history of use in Europe and China and they are becoming increasingly popular in the United States. However, little data is available regarding environmental contaminants in botanical dietary supplements and the risk posed to those ingest...

  16. Assessing diversity and phytoremediation potential of mangroves for copper contaminated sediments in Subic Bay, Philippines

    Science.gov (United States)

    Toxic metal pollution of water and soil is a major environmental problem and most conventional remediation approaches may not provide adequate solutions. An alternative way of reducing copper (Cu) concentration from contaminated sediments is through phytoremediation. Presently, there are few researc...

  17. Phytostabilization potential of ornamental plants grown in soil contaminated with cadmium.

    Science.gov (United States)

    Zeng, Peng; Guo, Zhaohui; Cao, Xia; Xiao, Xiyuan; Liu, Yanan; Shi, Lei

    2018-03-21

    In a greenhouse experiment, five ornamental plants, Osmanthus fragrans (OF), Ligustrum vicaryi L. (LV), Cinnamomum camphora (CC), Loropetalum chinense var. rubrum (LC), and Euonymus japonicas cv. Aureo-mar (EJ), were studied for the ability to phytostabilization for Cd-contaminated soil. The results showed that these five ornamental plants can grow normally when the soil Cd content is less than 24.6 mg·kg -1 . Cd was mainly deposited in the roots of OF, LV, LC and EJ which have grown in Cd-contaminated soils, and the maximum Cd contents reached 15.76, 19.09, 20.59 and 32.91 mg·kg -1 , respectively. For CC, Cd was mainly distributed in the shoots and the maximum Cd content in stems and leaves were 12.5 and 10.71 mg·kg -1 , however, the total amount of Cd in stems and leaves was similar with the other ornamental plants. The enzymatic activities in Cd-contaminated soil were benefited from the five tested ornamental plants remediation. Soil urease and sucrase activities were improved, while dehydrogenase activity was depressed. Meanwhile, the soil microbial community was slightly influenced when soil Cd content is less than 24.6 mg·kg -1 under five ornamental plants remediation. The results further suggested that ornamental plants could be promising candidates for phytostabilization of Cd-contaminated soil.

  18. Prediction of contamination potential of groundwater arsenic in Cambodia, Laos, and Thailand using artificial neural network

    Science.gov (United States)

    The arsenic (As) contamination of groundwater has increasingly been recognized as a major global issue of concern. As groundwater resources are one of most important freshwater sources for water supplies in Southeast Asian countries, it is important to investigate the spatial distribution of As cont...

  19. POTENTIAL REUSE OF PETROLEUM-CONTAMINATED SOIL: A DIRECTORY OF PERMITTED RECYCLING FACILITIES

    Science.gov (United States)

    Soil contaminated by virgin petroleum products leaking from underground storage tanks Is a pervasive problem in the United States. Economically feasible disposal of such soil concerns the responsible party (RP), whether the RP is one individual small business owner, a group o...

  20. Microbial activity in an acid resin deposit: Biodegradation potential and ecotoxicology in an extremely acidic hydrocarbon contamination

    International Nuclear Information System (INIS)

    Kloos, Karin; Schloter, Michael; Meyer, Ortwin

    2006-01-01

    Acid resins are residues produced in a recycling process for used oils that was in use in the forties and fifties of the last century. The resin-like material is highly contaminated with mineral oil hydrocarbons, extremely acidic and co-contaminated with substituted and aromatic hydrocarbons, and heavy metals. To determine the potential for microbial biodegradation the acid resin deposit and its surroundings were screened for microbial activity by soil respiration measurements. No microbial activity was found in the core deposit. However, biodegradation of hydrocarbons was possible in zones with a lower degree of contamination surrounding the deposit. An extreme acidophilic microbial community was detected close to the core deposit. With a simple ecotoxicological approach it could be shown that the pure acid resin that formed the major part of the core deposit, was toxic to the indigenous microflora due to its extremely low pH of 0-1. - Acidity is the major toxic factor of the extremely hydrophobic and acidic mixed contamination found in an acid resin deposit

  1. Engineered/designer biochar for contaminant removal/immobilization from soil and water: Potential and implication of biochar modification.

    Science.gov (United States)

    Rajapaksha, Anushka Upamali; Chen, Season S; Tsang, Daniel C W; Zhang, Ming; Vithanage, Meththika; Mandal, Sanchita; Gao, Bin; Bolan, Nanthi S; Ok, Yong Sik

    2016-04-01

    The use of biochar has been suggested as a means of remediating contaminated soil and water. The practical applications of conventional biochar for contaminant immobilization and removal however need further improvements. Hence, recent attention has focused on modification of biochar with novel structures and surface properties in order to improve its remediation efficacy and environmental benefits. Engineered/designer biochars are commonly used terms to indicate application-oriented, outcome-based biochar modification or synthesis. In recent years, biochar modifications involving various methods such as, acid treatment, base treatment, amination, surfactant modification, impregnation of mineral sorbents, steam activation and magnetic modification have been widely studied. This review summarizes and evaluates biochar modification methods, corresponding mechanisms, and their benefits for contaminant management in soil and water. Applicability and performance of modification methods depend on the type of contaminants (i.e., inorganic/organic, anionic/cationic, hydrophilic/hydrophobic, polar/non-polar), environmental conditions, remediation goals, and land use purpose. In general, modification to produce engineered/designer biochar is likely to enhance the sorption capacity of biochar and its potential applications for environmental remediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Hazard potential of widespread but hidden historic offshore heavy metal (Pb, Zn) contamination (Gulf of Cadiz, Spain).

    Science.gov (United States)

    Hanebuth, Till J J; King, Mary Lee; Mendes, Isabel; Lebreiro, Susana; Lobo, Francisco J; Oberle, Ferdinand K; Antón, Laura; Ferreira, Paulo Alves; Reguera, Maria Isabel

    2018-05-10

    Natural and human-induced seabed sediment disturbances affect wide areas of the global coastal ocean. These recurrent to chronic disturbances mobilize significant amounts of material, including substances that have the potential to significantly harm the environment once re-released. This very challenging issue is difficult to deal with if sub-surface contaminant concentrations are unknown. Based on the analysis of 11 new, up to 5-m long sediment cores taken offshore in the Gulf of Cadiz, the contamination history (using the trace elements lead and zinc) is well documented over major parts of the gulf. Ore mining and metal processing industries on the southwestern Iberian Peninsula started five thousand years ago and experienced a first peak during the Roman Period, which can be detected over the entire gulf. The Industrial Era added a massive, shelf-wide heavy metal excursion of unprecedented dimension. This metal contamination to the coastal ocean decreased in the 1990s and appears to be today limited to larger areas off the Tinto/Odiel and Guadiana River mouths. The unforeseen, significant finding of this study is that the gulf-wide, peak heavy metal concentration, stemming from the Industrial Era, is widely overlain by a modern sediment veneer just thick enough to cover the contaminant horizon, but thin enough to have this layer within the reach of natural or human-induced sediment mobilization events. Published by Elsevier B.V.

  3. Migration of a groundwater contaminant plume by stratabound flow in Waste Area Grouping 1 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Ketelle, R.H.; Lee, R.R.

    1992-08-01

    The discovery of radiologically contaminated groundwater in core hole CH-8 in the western portion of Waste Area Grouping (WAG) 1 at Oak Ridge National Laboratory (ORNL) prompted a detailed investigation to identify the contaminant plume. Utilizing a working hypothesis of stratabound groundwater flow and contaminant transport, investigators analyzed existing subsurface geologic data to predict the contaminant plume discharge location in first Creek and locations of contaminated groundwater seepage into storm drains. The hypothesis states that differential lithologic/fracture conditions lead to the development of preferred flow and transport pathways, of discrete vertical extent, which may not be coincident with the hydraulic gradient. Leakage out of the stratabound pathway is a minor component of the overall plume configuration

  4. An overview of some concepts, potentials, issues, and realities of assisted migration for climate change adaptation in forests

    Science.gov (United States)

    Louis R. Iverson; Matthew P. Peters; Stephen Matthews; Anantha. Prasad

    2013-01-01

    The climate has always been changing, but the rapid rate of climate change, as projected by the IPCC (2007) will likely place unique stresses on plant communities. In addition, anthropogenic barriers (e.g., fragmented land use) present a significant modern constraint that will limit the ability of species migration in responses to a changing climate. As such, managers...

  5. The potential influence of subduction zone polarity on overriding plate deformation, trench migration and slab dip angle

    NARCIS (Netherlands)

    Schellart, W. P.

    2007-01-01

    A geodynamic model exists, the westward lithospheric drift model, in which the variety of overriding plate deformation, trench migration and slab dip angles is explained by the polarity of subduction zones. The model predicts overriding plate extension, a fixed trench and a steep slab dip for

  6. Decreased proliferative, migrative and neuro-differentiative potential of postnatal rat enteric neural crest-derived cells during culture in vitro

    International Nuclear Information System (INIS)

    Yu, Hui; Pan, Wei-Kang; Zheng, Bai-Jun; Wang, Huai-Jie; Chen, Xin-Lin; Liu, Yong; Gao, Ya

    2016-01-01

    A growing body of evidence supports the potential use of enteric neural crest-derived cells (ENCCs) as a cell replacement therapy for Hirschsprung's disease. Based on previous observations of robust propagation of primary ENCCs, as opposed to their progeny, it is suggested that their therapeutic potential after in vitro expansion may be restricted. We therefore examined the growth and differentiation activities and phenotypic characteristics of continuous ENCC cultures. ENCCs were isolated from the intestines of postnatal rats and were identified using an immunocytochemical approach. During continuous ENCC culture expansion, proliferation, migration, apoptosis, and differentiation potentials were monitored. The Cell Counting Kit-8 was used for assessment of ENCC vitality, Transwell inserts for cell migration, immunocytochemistry for cell counts and identification, and flow cytometry for apoptosis. Over six continuous generations, ENCC proliferation potency was reduced and with prolonged culture, the ratio of migratory ENCCs was decreased. The percentage of apoptosis showed an upward trend with prolonged intragenerational culture, but showed a downward trend with prolonged culture of combined generations. Furthermore, the percentage of peripherin"+ cells decreased whilst the percentage of GFAP"+ cells increased with age. The results demonstrated that alterations in ENCC growth characteristics occur with increased culture time, which may partially account for the poor results of proposed cell therapies. - Highlights: • Differences were identified between primary and daughter ENCCs. • Daughter ENCCs had reduced proliferation, migration and differentiation. • Daughter ENCCs also had increased apoptosis. • These altered characteristics warrant further investigation.

  7. Decreased proliferative, migrative and neuro-differentiative potential of postnatal rat enteric neural crest-derived cells during culture in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hui [Department of Pediatric Surgery, the Second Affiliated Hospital, Xi’an Jiaotong University, No 157, Xi Wu Road, Xi’an 710004, Shaanxi (China); Institute of Neurobiology, Environment and Genes Related to Diseases Key Laboratory of Chinese Ministry of Education, Xi’an Jiaotong University, No 96, Yan Ta Xi Road, Xi’an 710061, Shaanxi (China); Pan, Wei-Kang; Zheng, Bai-Jun; Wang, Huai-Jie [Department of Pediatric Surgery, the Second Affiliated Hospital, Xi’an Jiaotong University, No 157, Xi Wu Road, Xi’an 710004, Shaanxi (China); Chen, Xin-Lin; Liu, Yong [Institute of Neurobiology, Environment and Genes Related to Diseases Key Laboratory of Chinese Ministry of Education, Xi’an Jiaotong University, No 96, Yan Ta Xi Road, Xi’an 710061, Shaanxi (China); Gao, Ya, E-mail: ygao@mail.xjtu.edu.cn [Department of Pediatric Surgery, the Second Affiliated Hospital, Xi’an Jiaotong University, No 157, Xi Wu Road, Xi’an 710004, Shaanxi (China)

    2016-05-01

    A growing body of evidence supports the potential use of enteric neural crest-derived cells (ENCCs) as a cell replacement therapy for Hirschsprung's disease. Based on previous observations of robust propagation of primary ENCCs, as opposed to their progeny, it is suggested that their therapeutic potential after in vitro expansion may be restricted. We therefore examined the growth and differentiation activities and phenotypic characteristics of continuous ENCC cultures. ENCCs were isolated from the intestines of postnatal rats and were identified using an immunocytochemical approach. During continuous ENCC culture expansion, proliferation, migration, apoptosis, and differentiation potentials were monitored. The Cell Counting Kit-8 was used for assessment of ENCC vitality, Transwell inserts for cell migration, immunocytochemistry for cell counts and identification, and flow cytometry for apoptosis. Over six continuous generations, ENCC proliferation potency was reduced and with prolonged culture, the ratio of migratory ENCCs was decreased. The percentage of apoptosis showed an upward trend with prolonged intragenerational culture, but showed a downward trend with prolonged culture of combined generations. Furthermore, the percentage of peripherin{sup +} cells decreased whilst the percentage of GFAP{sup +} cells increased with age. The results demonstrated that alterations in ENCC growth characteristics occur with increased culture time, which may partially account for the poor results of proposed cell therapies. - Highlights: • Differences were identified between primary and daughter ENCCs. • Daughter ENCCs had reduced proliferation, migration and differentiation. • Daughter ENCCs also had increased apoptosis. • These altered characteristics warrant further investigation.

  8. A probabilistic risk assessment for the Kirtland's warbler potentially exposed to chlorpyrifos and malathion during the breeding season and migration.

    Science.gov (United States)

    Moore, Dwayne Rj; Priest, Colleen D; Olson, Adric D; Teed, R Scott

    2018-03-01

    Two organophosphate pesticides, chlorpyrifos and malathion, are currently undergoing reregistration in the United States and were recently used by the US Environmental Protection Agency (USEPA) as case studies to develop a national procedure for evaluating risks to endangered species. One of the endangered bird species considered by the USEPA was the Kirtland's warbler (Setophaga kirtlandii). The Kirtland's warbler is an endangered migratory species that nests exclusively in young jack pine stands in Michigan and Wisconsin, and winters in the Bahamas. We developed probabilistic models to assess the risks of chlorpyrifos and malathion to Kirtland's warblers during the breeding season and the spring and fall migrations. The breeding area model simulates acute and chronic exposure and risk to each of 10 000 birds over a 60-d period following initial pesticide application. The model is highly species specific with regard to the foraging behavior of Kirtland's warblers during the breeding season. We simulated the maximum application rate and number of applications allowed on the labels for representative use patterns that could be found within 3 km of the breeding areas of Kirtland's warbler. The migration model simulates 10 000 birds during the course of their 12- to 23-d migration between their breeding area and the Bahamas. The model takes advantage of more than a century of observations of when, where, and for how long Kirtland's warblers forage in different habitats during the course of their migration. The data indicate that warblers only infrequently stop over in habitats that could be treated with chlorpyrifos and malathion. The breeding area and migration models resulted in predictions of very low acute and chronic risk for both pesticides to Kirtland's warblers. These results were expected, given that field observations indicate that the Kirtland's warbler has dramatically increased in abundance in recent decades. Integr Environ Assess Manag 2018

  9. Development and characterization of activated hydrochars from orange peels as potential adsorbents for emerging organic contaminants.

    Science.gov (United States)

    Fernandez, M E; Ledesma, B; Román, S; Bonelli, P R; Cukierman, A L

    2015-05-01

    Activated hydrochars obtained from the hydrothermal carbonization of orange peels (Citrus sinensis) followed by various thermochemical processing were assessed as adsorbents for emerging contaminants in water. Thermal activation under flows of CO2 or air as well as chemical activation with phosphoric acid were applied to the hydrochars. Their characteristics were analyzed and related to their ability to uptake three pharmaceuticals (diclofenac sodium, salicylic acid and flurbiprofen) considered as emerging contaminants. The hydrothermal carbonization and subsequent activations promoted substantial chemical transformations which affected the surface properties of the activated hydrochars; they exhibited specific surface areas ranging from 300 to ∼620 m(2)/g. Morphological characterization showed the development of coral-like microspheres dominating the surface of most hydrochars. Their ability to adsorb the three pharmaceuticals selected was found largely dependent on whether the molecules were ionized or in their neutral form and on the porosity developed by the new adsorbents. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Evaluation of tolerance to soils contaminated with diesel oil in plant species with bioremediation potential

    International Nuclear Information System (INIS)

    Petenello, Maria Cristina; Feldman, Susana Raquel.

    2012-01-01

    Soils contaminated with hydrocarbons or their derivate can be remediated by different methods. Many of them use live organisms such as plants that are able to mineralize these compounds, turning them into more simple molecules, similar to natural molecules. When the use of plants is decided, it is important to employ native plants because they are already adapted to the particular ecological conditions of the site. The response of spartina argentinensis, paspalum atratum, paspalum guenoarun and melilotus albus to the presence of diesel oil was evaluated considering seed germination, plant emergence and biomass production of plants growing on soils experimentally contaminated with different concentrations of diesel oil (1 and 2 %). Although all the parameters evaluated showed the negative impact of the presence of diesel-oil, the plants continued growing; therefore they can be considered useful management options for soil phytoremediation.

  11. Potential airborne release from soil-working operations in a contaminated area

    International Nuclear Information System (INIS)

    Sutter, S.L.

    1980-08-01

    Experiments were performed to provide an indication of how much material could be made airborne during soil-working operations in a contaminated area. Approximately 50 kg of contaminated soil were collected, dried, and mixed, and particle size distribution and 137 Cs content were characterized. In four experiments performed in a 2 ft x 2 ft wind tunnel at the Radioactive Aerosol Release Test Facility, soil was pumped into an airstream moving at 3.2, 10.4, 15.2, and 20 mph. These experiments were designed to maximize airborne releases by fluidizing the soil as it was pumped into the wind tunnel. Thus the airborne releases should represent upper limit values for soil-working operations. Airborne concentration and particle size samples were collected and all of the material deposited downstream was collected to calculate a mass balance. The fraction airborne was calculated using these measurements

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

    International Nuclear Information System (INIS)

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

    1996-08-01

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

  13. Heavy metal contamination in the muscle of Aegean chub (Squalius fellowesii) and potential risk assessment.

    Science.gov (United States)

    Şaşi, Hüseyin; Yozukmaz, Aykut; Yabanli, Murat

    2018-03-01

    Especially after the industrial revolution, the amount of contaminants released in aquatic ecosystems has considerably increased. For this reason, the necessity to carry on research on the existence of contaminants, specifically heavy metals, has emerged. In this study, heavy metal concentrations in muscle tissues of Aegean chub, which was an endemic species of south western part of Turkey, gathered from Tersakan River were examined. Heavy metal concentrations of the samples were analyzed with ICP-MS. Estimated daily intakes (EDI), target hazard quotient (THQ), and carcinogenic risk (CR) of elements were calculated. The heavy metals detected in muscle tissues were Zn > Cu > Cr > Mn > Pb > Cd, consecutively. According to the results of the applied health risk assessment (EDI, THQ and CR) for heavy metal exposure from fish consumption in children and adults, it was determined that there was no any significant threat to human health.

  14. CONTAMINANTS AND REMEDIAL OPTIONS AT PESTICIDE SITES

    Science.gov (United States)

    Many types of soils, sediments, and sludges are contaminated with a wide variety of pesticides. ite-specific characteristics such as volume to be treated, extent of contamination, and applicable cleanup goals differ greatly, and contaminant toxicity, migration pathways, persisten...

  15. Potential of sunflower (helianthus annuus L.) for phytoremediation of nickle (Ni) and lead (Pb) contaminated water

    International Nuclear Information System (INIS)

    Mukhtar, S.M.; HAQ Bhatti, H.N.; Khalid, M.; Haq, M.A; Shahzad, S.M.

    2010-01-01

    Heavy metals are contaminants of much environmental apprehension, as they are hazardous to human being and other biota. Buildup of heavy metals in crop plants is of great concern due to the probability of food contamination through the soil-root interface. For this purpose, a hydroponic study was conducted to evaluate the efficacy of sunflower plant to phytoremediate Pb and Ni contaminated water in the absence and presence of synthetic chelator. Results showed that application of Ni and Pb reduced the dry weights of shoot and root (up to 55.1 and 38.3%; 50.5 and 33.6%), shoot and root length (up to 64.5 and 58.1%; 64.1 and 55.8%), chlorophyll content (up to 63.8 and 54.4%), and photosynthetic activity (up to 66.1 and 62.7%), respectively with EDTA as compared to control. While, maximum concentration of Ni and Pb in shoot and root (up to 18.43 and 20.73 mg kg/sup -1/; 12.82 and 18.67 mg kg/sup -1/), total accumulation (up to 55.82 and 72.28 mg kg/sup -1/), and proline content (up to 128.2 and 98.3%) were recorded in the presence of EDTA respectively as compared to control. Generally, it was observed that concentration and total accumulation of Pb was more than Ni in sunflower plant. The study concludes that the use of synthetic chelator increased the uptake and translocation of heavy metals in plant biomass that could enhance the phytoremediation of Ni and Pb from contaminated water. (author)

  16. Characterization and Potential Remediation Approaches for Vadose Zone Contamination at Hanford 241-SX Tank Farm - 13235

    Energy Technology Data Exchange (ETDEWEB)

    Eberlein, Susan J.; Sydnor, Harold A.; Parker, Danny L.; Glaser, Danney R. [Washington River Protection Solutions, P.O. Box 850, Richland, WA, 99352 (United States)

    2013-07-01

    Unplanned releases of radioactive and hazardous wastes have occurred at the 241-SX Tank Farm on the U.S. Department of Energy Hanford Site in southeast Washington State. Interim and long-term mitigation efforts are currently under evaluation for 241-SX Tank Farm. Two contiguous interim surface barriers have been designed for deployment at 241-SX Tank Farm to reduce future moisture infiltration; however, construction of the surface barriers has been deferred to allow testing of alternative technologies for soil moisture reduction and possibly contaminant source term reduction. Previous tests performed by other organizations at the Hanford Site have demonstrated that: vadose zone desiccation using large diameter (greater than 4 inch) boreholes is feasible; under certain circumstances, mobile contaminants may be removed in addition to water vapor; and small diameter (approximately 2 inch) boreholes (such as those placed by the direct push hydraulic hammer) can be used to perform vapor extractions. Evaluation of the previous work combined with laboratory test results have led to the design of a field proof-of-principle test to remove water and possibly mobile contaminants at greater depths, using small boreholes placed with the direct push unit. (authors)

  17. Characterization and Potential Remediation Approaches for Vadose Zone Contamination at Hanford 241-SX Tank Farm-13235

    International Nuclear Information System (INIS)

    Eberlein, Susan J.; Sydnor, Harold A.; Parker, Danny L.; Glaser, Danney R.

    2013-01-01

    Unplanned releases of radioactive and hazardous wastes have occurred at the 241-SX Tank Farm on the U.S. Department of Energy Hanford Site in southeast Washington State. Interim and long-term mitigation efforts are currently under evaluation for 241-SX Tank Farm. Two contiguous interim surface barriers have been designed for deployment at 241-SX Tank Farm to reduce future moisture infiltration; however, construction of the surface barriers has been deferred to allow testing of alternative technologies for soil moisture reduction and possibly contaminant source term reduction. Previous tests performed by other organizations at the Hanford Site have demonstrated that: vadose zone desiccation using large diameter (greater than 4 inch) boreholes is feasible; under certain circumstances, mobile contaminants may be removed in addition to water vapor; and small diameter (approximately 2 inch) boreholes (such as those placed by the direct push hydraulic hammer) can be used to perform vapor extractions. Evaluation of the previous work combined with laboratory test results have led to the design of a field proof-of-principle test to remove water and possibly mobile contaminants at greater depths, using small boreholes placed with the direct push unit

  18. Potential of grasses and rhizosphere bacteria for bioremediation of diesel-contaminated soils

    Directory of Open Access Journals (Sweden)

    Melissa Paola Mezzari

    2011-12-01

    Full Text Available The techniques available for the remediation of environmental accidents involving petroleum hydrocarbons are generally high-cost solutions. A cheaper, practical and ecologically relevant alternative is the association of plants with microorganisms that contribute to the degradation and removal of hydrocarbons from the soil. The growth of three tropical grass species (Brachiaria brizantha, Brachiaria decumbens and Paspalum notatum and the survival of root-associated bacterial communities was evaluated at different diesel oil concentrations. Seeds of three grass species were germinated in greenhouse and at different doses of diesel (0, 2.5, 5 and 10 g kg-1 soil. Plants were grown for 10 weeks with periodic assessment of germination, growth (fresh and dry weight, height, and number of bacteria in the soil (pots with or without plants. Growth and biomass of B. decumbens and P. notatum declined significantly when planted in diesel-oil contaminated soils. The presence of diesel fuel did not affect the growth of B. brizantha, which was highly tolerant to this pollutant. Bacterial growth was significant (p < 0.05 and the increase was directly proportional to the diesel dose. Bacteria growth in diesel-contaminated soils was stimulated up to 5-fold by the presence of grasses, demonstrating the positive interactions between rhizosphere and hydrocarbon-degrading bacteria in the remediation of diesel-contaminated soils.

  19. Occurrence and potential crop uptake of emerging contaminants and related compounds in an agricultural irrigation network

    International Nuclear Information System (INIS)

    Calderón-Preciado, Diana; Matamoros, Víctor; Bayona, Josep M.

    2011-01-01

    Emerging contaminants have received much attention in recent years due to their presence in surface waters, but little attention has been paid to their occurrence in agricultural irrigation waters. This study investigated the occurrence of these compounds in an agricultural irrigation network in northeastern Spain and, for the first time, using two plant uptake models, estimated the concentration of selected micropollutants in crops. The concentration of micropollutants in agricultural irrigation waters ranged from 10 to 5130 ng L −1 and exhibited some attenuation over the course of the irrigation network. Bromoform, chloroform, diclofenac, caffeine, ibuprofen, naproxen, methyl dihydrojasmonate, galaxolide, butylated hydroxytoluene, and butylated hydroxyanisole were the most abundant contaminants (> 200 ng L −1 , on average). The estimated concentration of micropollutants in crops ranged from −1 , with the neutral compounds being the most abundant. Moreover, the predicted data obtained by fate models generally agreed with experimental data. Finally, human exposure to micropollutants through fruit and vegetable consumption was estimated to be 9.8 μg per person and week (Σ 27 contaminants detected). Further studies are needed to determine the health implications that the presence of these compounds in fruit and vegetables may have for consumers.

  20. A review of biochars' potential role in the remediation, revegetation and restoration of contaminated soils

    International Nuclear Information System (INIS)

    Beesley, Luke; Moreno-Jimenez, Eduardo; Gomez-Eyles, Jose L.; Harris, Eva; Robinson, Brett; Sizmur, Tom

    2011-01-01

    Biochars are biological residues combusted under low oxygen conditions, resulting in a porous, low density carbon rich material. Their large surface areas and cation exchange capacities, determined to a large extent by source materials and pyrolysis temperatures, enables enhanced sorption of both organic and inorganic contaminants to their surfaces, reducing pollutant mobility when amending contaminated soils. Liming effects or release of carbon into soil solution may increase arsenic mobility, whilst low capital but enhanced retention of plant nutrients can restrict revegetation on degraded soils amended only with biochars; the combination of composts, manures and other amendments with biochars could be their most effective deployment to soils requiring stabilisation by revegetation. Specific mechanisms of contaminant-biochar retention and release over time and the environmental impact of biochar amendments on soil organisms remain somewhat unclear but must be investigated to ensure that the management of environmental pollution coincides with ecological sustainability. - Highlights: → Biochars can reduce mobilities of some organic and inorganic pollutants in soil. → Source material and production conditions influence pollutant retention. → Highly alkaline pH and water soluble carbon can undesirably mobilise some elements. → Large surface area may be toxic to soil fauna but create microbial niches. → Efficacy of biochar may depend on other organic materials applied in combination. - Biochars can reduce the mobility and impact of some soil pollutants but, if applied alone, may fail to support soil restoration, revegetation and hence ecologically circumspect remediation.

  1. Potential and drawbacks of EDDS-enhanced phytoextraction of copper from contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Komarek, Michael, E-mail: komarek@af.czu.c [Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamycka 129, 165 21 Prague 6 (Czech Republic); Vanek, Ales [Department of Soil Science and Soil Protection, Czech University of Life Sciences Prague, Kamycka 129, 165 21 Prague 6 (Czech Republic); Mrnka, Libor; Sudova, Radka [Department of Mycorrhizal Symbioses, Institute of Botany, Academy of Sciences of the Czech Republic, Lesni 322, 252 43 Pruhonice (Czech Republic); Szakova, Jirina [Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamycka 129, 165 21 Prague 6 (Czech Republic); Tejnecky, Vaclav [Department of Soil Science and Soil Protection, Czech University of Life Sciences Prague, Kamycka 129, 165 21 Prague 6 (Czech Republic); Chrastny, Vladislav [Czech Geological Survey, Geologicka 6, 152 00 Prague 5 (Czech Republic); Faculty of Science, University of South Bohemia, Branisovska 31, 370 05 Ceske Budejovice (Czech Republic)

    2010-07-15

    Incubation and pot experiments using poplar (Populus nigra L. cv. Wolterson) were performed in order to evaluate the questionable efficiency of EDDS-enhanced phytoextraction of Cu from contaminated soils. Despite the promising conditions of the experiment (low contamination of soils with a single metal with a high affinity for EDDS, metal tolerant poplar species capable of producing high biomass yields, root colonization by mycorrhizal fungi), the phytoextraction efficiency was not sufficient. The EDDS concentrations used in this study (3 and 6 mmol kg{sup -1}) enhanced the mobility (up to a 100-fold increase) and plant uptake of Cu (up to a 65-fold increase). However, despite EDDS degradation and the competition of Fe and Al for the chelant, Cu leaching cannot be omitted during the process. Due to the low efficiency, further research should be focused on other environment-friendly methods of soil remediation. - Research focused on EDDS-enhanced phytoextraction of metals from contaminated soils has probably reached a dead-end.

  2. Occurrence and potential crop uptake of emerging contaminants and related compounds in an agricultural irrigation network

    Energy Technology Data Exchange (ETDEWEB)

    Calderon-Preciado, Diana [IDAEA-CSIC, Jordi Girona, 18, E-08034 Barcelona (Spain); Matamoros, Victor, E-mail: victor.matamoros@udg.edu [Department of Chemistry, University of Girona, Campus Montilivi, 17071 Girona (Spain); Bayona, Josep M. [IDAEA-CSIC, Jordi Girona, 18, E-08034 Barcelona (Spain)

    2011-12-15

    Emerging contaminants have received much attention in recent years due to their presence in surface waters, but little attention has been paid to their occurrence in agricultural irrigation waters. This study investigated the occurrence of these compounds in an agricultural irrigation network in northeastern Spain and, for the first time, using two plant uptake models, estimated the concentration of selected micropollutants in crops. The concentration of micropollutants in agricultural irrigation waters ranged from 10 to 5130 ng L{sup -1} and exhibited some attenuation over the course of the irrigation network. Bromoform, chloroform, diclofenac, caffeine, ibuprofen, naproxen, methyl dihydrojasmonate, galaxolide, butylated hydroxytoluene, and butylated hydroxyanisole were the most abundant contaminants (> 200 ng L{sup -1}, on average). The estimated concentration of micropollutants in crops ranged from < 1 to 7677 ng kg{sup -1}, with the neutral compounds being the most abundant. Moreover, the predicted data obtained by fate models generally agreed with experimental data. Finally, human exposure to micropollutants through fruit and vegetable consumption was estimated to be 9.8 {mu}g per person and week ({Sigma} 27 contaminants detected). Further studies are needed to determine the health implications that the presence of these compounds in fruit and vegetables may have for consumers.

  3. Potential and drawbacks of EDDS-enhanced phytoextraction of copper from contaminated soils

    International Nuclear Information System (INIS)

    Komarek, Michael; Vanek, Ales; Mrnka, Libor; Sudova, Radka; Szakova, Jirina; Tejnecky, Vaclav; Chrastny, Vladislav

    2010-01-01

    Incubation and pot experiments using poplar (Populus nigra L. cv. Wolterson) were performed in order to evaluate the questionable efficiency of EDDS-enhanced phytoextraction of Cu from contaminated soils. Despite the promising conditions of the experiment (low contamination of soils with a single metal with a high affinity for EDDS, metal tolerant poplar species capable of producing high biomass yields, root colonization by mycorrhizal fungi), the phytoextraction efficiency was not sufficient. The EDDS concentrations used in this study (3 and 6 mmol kg -1 ) enhanced the mobility (up to a 100-fold increase) and plant uptake of Cu (up to a 65-fold increase). However, despite EDDS degradation and the competition of Fe and Al for the chelant, Cu leaching cannot be omitted during the process. Due to the low efficiency, further research should be focused on other environment-friendly methods of soil remediation. - Research focused on EDDS-enhanced phytoextraction of metals from contaminated soils has probably reached a dead-end.

  4. Heavy metal accumulation and phytostabilisation potential of tree fine roots in a contaminated soil

    International Nuclear Information System (INIS)

    Brunner, Ivano; Luster, Joerg; Guenthardt-Goerg, Madeleine S.; Frey, Beat

    2008-01-01

    Root systems of Norway spruce (Picea abies) and poplar (Populus tremula) were long-term exposed to metal-contaminated soils in open-top chambers to investigate the accumulation of the heavy metals in the fine roots and to assess the plants suitability for phytostabilisation. The heavy metals from the contaminated soil accumulated in the fine roots about 10-20 times more than in the controls. The capacity to bind heavy metals already reached its maximum after the first vegetation period. Fine roots of spruce tend to accumulate more heavy metals than poplar. Copper and Zinc were mainly detected in the cell walls with larger values in the epidermis than in the cortex. The heavy metals accumulated in the fine roots made up 0.03-0.2% of the total amount in the soils. We conclude that tree fine roots adapt well to conditions with heavy metal contamination, but their phytostabilisation capabilities seem to be very low. - Long-term exposed fine roots of trees are well adapted to soils with high heavy metal contents, but their phytostabilisation capabilities are rather low

  5. Nanoscale zerovalent iron alters soil bacterial community structure and inhibits chloroaromatic biodegradation potential in Aroclor 1242-contaminated soil

    International Nuclear Information System (INIS)

    Tilston, Emma L.; Collins, Chris D.; Mitchell, Geoffrey R.; Princivalle, Jessica; Shaw, Liz J.

    2013-01-01

    Nanoscale zerovalent iron (nZVI) has potential for the remediation of organochlorine-contaminated environments. Environmental safety concerns associated with in situ deployment of nZVI include potential negative impacts on indigenous microbes whose biodegradative functions could contribute to contaminant remediation. With respect to a two-step polychlorinated biphenyl remediation scenario comprising nZVI dechlorination followed by aerobic biodegradation, we examined the effect of polyacrylic acid (PAA)-coated nZVI (mean diameter = 12.5 nm) applied at 10 g nZVI kg −1 to Aroclor-1242 contaminated and uncontaminated soil over 28 days. nZVI had a limited effect on Aroclor congener profiles, but, either directly or indirectly via changes to soil physico-chemical conditions (pH, Eh), nZVI addition caused perturbation to soil bacterial community composition, and reduced the activity of chloroaromatic mineralizing microorganisms. We conclude that nZVI addition has the potential to inhibit microbial functions that could be important for PCB remediation strategies combining nZVI treatment and biodegradation. Highlights: ► Impact of nano-sized zerovalent iron on microbes was investigated in soil microcosms. ► Zerovalent iron had short-lived effects on redox potential and Aroclor dechlorination. ► Microbial populations also showed short-lived perturbations in their size. ► The activity of chloroaromatic degrading microbes did not recover within 28 days. ► Zerovalent iron application inhibits ensuing PCB bioremediative microbial functions. - nZVI inhibits microbial functions of potential importance for remediation strategies combining nZVI treatment and biodegradation.

  6. Toxicological benchmarks for screening contaminants of potential concern for effects on sediment-associated biota: 1996 revision

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.S.; Suter, G.W. II [Oak Ridge National Lab., TN (United States); Hull, R.N. [Beak Consultants Ltd., Brampton, ON (Canada)

    1996-06-01

    A hazardous waste site may contain hundred of chemicals; therefore, it is important to screen contaminants of potential concern of the ecological risk assessment. Often this screening is done as part of a Screening Assessment, the purpose of which is to evaluate the available data, identify data gaps, and screen contaminants of potential concern. |Screening may be accomplished by using a set of toxicological benchmarks. These benchmarks are helpful in determining whether contaminants warrant further assessment or are at a level that requires no further attention. If a chemical concentration or the reported detection limit exceeds a proposed lower benchmark, more analysis is needed to determine the hazards posed by that chemical. If, however, the chemical concentration falls below the lower benchmark value, the chemical may be eliminated from further study. This report briefly describes three categories of approaches to the development of sediment quality benchmarks. These approaches are based on analytical chemistry, toxicity test results, and field survey data. A fourth integrative approach incorporates all three types of data.

  7. Functional genes reveal the intrinsic PAH biodegradation potential in creosote-contaminated groundwater following in situ biostimulation.

    Science.gov (United States)

    Nyyssönen, Mari; Kapanen, Anu; Piskonen, Reetta; Lukkari, Tuomas; Itävaara, Merja

    2009-08-01

    A small-scale functional gene array containing 15 functional gene probes targeting aliphatic and aromatic hydrocarbon biodegradation pathways was used to investigate the effect of a pilot-scale air sparging and nutrient infiltration treatment on hydrocarbon biodegradation in creosote-contaminated groundwater. Genes involved in the different phases of polycyclic aromatic hydrocarbon (PAH) biodegradation were detected with the functional gene array in the contaminant plume, thus indicating the presence of intrinsic biodegradation potential. However, the low aerobic fluorescein diacetate hydrolysis, the polymerase chain reaction (PCR) amplification of 16S rRNA genes closely similar to sulphate-reducing and denitrifying bacteria and the negligible decrease in contaminant concentrations showed that aerobic PAH biodegradation was limited in the anoxic groundwater. Increased abundance of PAH biodegradation genes was detected by functional gene array in the monitoring well located at the rear end of the biostimulated area, which indicated that air sparging and nutrient infiltration enhanced the intrinsic, aerobic PAH biodegradation. Furthermore, ten times higher naphthalene dioxygenase gene copy numbers were detected by real-time PCR in the biostimulated area, which was in good agreement with the functional gene array data. As a result, functional gene array analysis was demonstrated to provide a potential tool for evaluating the efficiency of the bioremediation treatment for enhancing hydrocarbon biodegradation in field-scale applications.

  8. Recent developments for in situ treatment of metal contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Metals contamination is a common problem at hazardous waste sites. This report assists the remedy selection process by providing information on four in situ technologies for treating soil contaminated with metals. The four approaches are electrokinetic remediation, phytoremediation, soil flushing, and solidification/stabilization. Electrokinetic remediation separates contaminants from soil through selective migration upon application of an electric current. Phytoremediation is an emerging technology that uses plants to isolate or stabilize contaminants. Soil flushing techniques promote mobility and migration of metals by solubilizing contaminants so that they can be recovered. Two types of in situ solidification/stabilization (S/S) techniques are discussed, one based on addition of reagents and the other based on the use of energy. The report discusses different techniques currently in practice or under development, identifies vendors and summarizes performance data, and discusses technology attributes that should be considered during early screening of potential remedies. 8 refs., 9 figs., 9 tabs., 2 apps.

  9. An alternative proposal for the disposal of potentially contaminated railroad crossties at the Savannah River Site. Revision 1

    International Nuclear Information System (INIS)

    Hochel, R.C.

    1996-06-01

    The Savannah River Site (SRS) has accumulated approximately 300,000 crossties that have been replaced over a 40-year period of maintaining the site's 62 miles of railroad track. The ties reside in a pile on an open area of 2.3 acres near the site's F-Area facilities. A small fraction of the ties are potentially contaminated with radioactivity as a result of past site practices and service. Contamination was possible from occasional leaks in transport-casks moved by rail from the site's five nuclear materials production reactors to its two reprocessing facilities. Casks typically were filled with spent fuel, targets, and water from the reactor disassembly basins, which contained small amounts of fission and neutron activation product radioactivity normal to the operation of nuclear reactors

  10. Toxicological benchmarks for potential contaminants of concern for effects on soil and litter invertebrates and heterotrophic process

    Energy Technology Data Exchange (ETDEWEB)

    Will, M.E.; Suter, G.W. II

    1995-09-01

    An important step in ecological risk assessments is screening the chemicals occur-ring on a site for contaminants of potential concern. Screening may be accomplished by comparing reported ambient concentrations to a set of toxicological benchmarks. Multiple endpoints for assessing risks posed by soil-borne contaminants to organisms directly impacted by them have been established. This report presents benchmarks for soil invertebrates and microbial processes and addresses only chemicals found at United States Department of Energy (DOE) sites. No benchmarks for pesticides are presented. After discussing methods, this report presents the results of the literature review and benchmark derivation for toxicity to earthworms (Sect. 3), heterotrophic microbes and their processes (Sect. 4), and other invertebrates (Sect. 5). The final sections compare the benchmarks to other criteria and background and draw conclusions concerning the utility of the benchmarks.

  11. Estimating the number of airports potentially contaminated with perfluoroalkyl and polyfluoroalkyl substances from aqueous film forming foam: A Canadian example.

    Science.gov (United States)

    Milley, Shawn A; Koch, Iris; Fortin, Patricia; Archer, Jeremy; Reynolds, David; Weber, Kela P

    2018-09-15

    Assessing the extent to which emerging contaminants (ECs) such as perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been released into the environment is one of the foundations for developing effective management and remediation strategies for impacted sites. PFAS are known to have caused the contamination of soil, groundwater, and surface water as a result of aqueous film forming foam (AFFF) being accidentally or intentionally released into the environment. To date, the scope of the issue has not been evaluated in Canada. In this study we developed a framework, in the form of a decision tree, to estimate the number of potentially PFAS impacted airport sites in Canada as a result of AFFF releases. The screening process was completed using publicly available resources including airport websites, the Canadian Owners and Pilots Association website, Sky Vector, Transport Safety Board of Canada aviation investigation reports, the Aviation Safety Network website, and Google maps. The methodology presented in this study could be used to identify additional PFAS impacted sites in Canada or other jurisdictions worldwide. 2071 airport/heliport sites in Canada were investigated with indications that 152 (7%) of these sites likely have PFAS contamination as a result of the use of AFFF at firefighter training areas (FFTAs) and/or accidents where fires occurred. In addition, another 268 sites (13%) were identified as possibly impacted with PFASs primarily as a result of the location having the ability to store and dispense petroleum products, and therefore having AFFF systems onsite. Surficial geology was also identified for all sites determined to likely have PFAS contamination. An estimated 42.8% had surficial geology composed of sand, 27% had clay, 19.7% organic-based, with the remaining sites found on cryosols or rock. Methodological validation was also completed. The procedure used in this study successfully predicted occurrences of PFAS contamination at 25 sites

  12. GIS-based assessment of the biomass potential from phytoremediation of contaminated agricultural land in the Campine region in Belgium

    International Nuclear Information System (INIS)

    Schreurs, Eloi; Voets, Thomas; Thewys, Theo

    2011-01-01

    Dedicated energy crop cultivation is expected to be the prevalent form of biomass production for reaching renewable energy targets set by the European Union. However, there are some concerns with regard to its sustainability. This study demonstrates how this problem can be evaded by applying phytoremediation, i.e. the use of plants to remove pollutants from moderately contaminated soils. By selecting the appropriate plants a considerable biomass flow is produced without taking in scarce agricultural land, while simultaneously remediating the soil to levels of contamination below threshold values. Since phytoremediation is only applicable within a limited range of soil pollutant concentrations, the outer values of this range have to be determined at first. Subsequently, a Geographic Information System (GIS) is needed to perform further analyses. The contamination in the region is predicted using GIS, after which the agricultural area is determined that can be committed to energy crop cultivation. This way, the biomass potential and the resulting bioenergy potential from phytoremediation can be assessed. In this paper the Campine region in Belgium, a region diffusely contaminated with heavy metals like cadmium (Cd), is examined. It is illustrated that more than 2000 ha of agricultural land hold Cd concentrations exceeding guide values set by the Flemish Government. However, a large majority of these soils can be remediated by phytoremediation within a reasonable time span of 42 years. Concurrently, a significant amount of biomass is supplied for renewable energy production. -- Highlights: → More than 2000 ha of agricultural land have elevated Cd concentrations. → 87% can be remediated within 42 years by phytoremediation. → Annual biomass flow of 19 067 Mg for 21 years.

  13. Toxicological benchmarks for screening contaminants of potential concern for effects on sediment-associated biota: 1994 Revision. Environmental Restoration Program

    International Nuclear Information System (INIS)

    Hull, R.N.; Suter, G.W. II

    1994-06-01

    Because a hazardous waste site may contain hundreds of chemicals, it is important to screen contaminants of potential concern for the ecological risk assessment. Often this screening is done as part of a Screening Assessment, the purpose of which is to evaluate the available data, identify data gaps, and screen contaminants of potential concern. Screening may be accomplished by using a set of toxicological benchmarks. These benchmarks are helpful in determining whether contaminants warrant further assessment or are at a level that requires no further attention. If a chemical concentration or the reported detection limit exceeds a proposed lower benchmark, more analysis is needed to determine the hazards posed by that chemical. If, however, the chemical concentration falls below the lower benchmark value, the chemical may be eliminated from further study. This report briefly describes three categories of approaches to the development of sediment quality benchmarks. These approaches are based on analytical chemistry, toxicity test and field survey data. A fourth integrative approach incorporates all three types of data. The equilibrium partitioning approach is recommended for screening nonpolar organic contaminants of concern in sediments. For inorganics, the National Oceanic and Atmospheric Administration has developed benchmarks that may be used for screening. There are supplemental benchmarks from the province of Ontario, the state of Wisconsin, and US Environmental Protection Agency Region V. Pore water analysis is recommended for polar organic compounds; comparisons are then made against water quality benchmarks. This report is an update of a prior report. It contains revised ER-L and ER-M values, the five EPA proposed sediment quality criteria, and benchmarks calculated for several nonionic organic chemicals using equilibrium partitioning

  14. 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.

  15. Migration from the Middle East and North Africa to Europe: Past Developments, Current Status and Future Potentials

    OpenAIRE

    2014-01-01

    One of the most important challenges concerning the future of the European Union is the demographic reproduction of the European population. Decreasing birth-rates and the retirement of the baby boomers will dramatically reduce the labour force in the EU, which will entail not only a lack of manpower but also lower contributions to European social systems. It seems clear that the EU will have to counterbalance this population decrease by immigration in the coming years. Migration Between the ...

  16. Potential of qualitative network analysis in migration studies- Reflections based on an empirical analysis of young researchers' mobility aspirations

    OpenAIRE

    Elisabeth Scheibelhofer

    2011-01-01

    Based on the example of an empirical research study, the paper examines the strengths and limitations of a qualitative network approach to migration and mobility. The method of graphic drawings produced by the respondents within an interview setting was applied. With this method, we argue to be able to analyse migrants’ specific social embeddedness and its influence on future mobility aspirations. Likewise, connections between the migratory biography and the individuals’ various social relati...

  17. Seasonally and regionally determined indication potential of bioassays in contaminated river sediments.

    Science.gov (United States)

    Hilscherová, Klára; Dusek, Ladislav; Sídlová, Tereza; Jálová, Veronika; Cupr, Pavel; Giesy, John P; Nehyba, Slavomír; Jarkovský, Jirí; Klánová, Jana; Holoubek, Ivan

    2010-03-01

    River sediments are a dynamic system, especially in areas where floods occur frequently. In the present study, an integrative approach is used to investigate the seasonal and spatial dynamics of contamination of sediments from a regularly flooded industrial area in the Czech Republic, which presents a suitable model ecosystem for pollutant distribution research at a regional level. Surface sediments were sampled repeatedly to represent two different hydrological situations: spring (after the peak of high flow) and autumn (after longer period of low flow). Samples were characterized for abiotic parameters and concentrations of priority organic pollutants. Toxicity was assessed by Microtox test; genotoxicity by SOS-chromotest and green fluorescent protein (GFP)-yeast test; and the presence of compounds with specific mode of action by in vitro bioassays for dioxin-like activity, anti-/androgenicity, and anti-/estrogenicity. Distribution of organic contaminants varied among regions and seasonally. Although the results of Microtox and genotoxicity tests were relatively inconclusive, all other specific bioassays led to statistically significant regional and seasonal differences in profiles and allowed clear separation of upstream and downstream regions. The outcomes of these bioassays indicated an association with concentrations of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) as master variables. There were significant interrelations among dioxin-like activity, antiandrogenicity and content of organic carbon, clay, and concentration of PAHs and PCBs, which documents the significance of abiotic factors in accumulation of pollutants. The study demonstrates the strength of the specific bioassays in indicating the changes in contamination and emphasizes the crucial role of a well-designed sampling plan, in which both spatial and temporal dynamics should be taken into account, for the correct interpretations of information in risk assessments.

  18. Development of an Efficient Bacterial Consortium for the Potential Remediation of Hydrocarbons from Contaminated Sites.

    Science.gov (United States)

    Patowary, Kaustuvmani; Patowary, Rupshikha; Kalita, Mohan C; Deka, Suresh

    2016-01-01

    The intrinsic biodegradability of hydrocarbons and the distribution of proficient degrading microorganisms in the environment are very crucial for the implementation of bioremediation practices. Among others, one of the most favorable methods that can enhance the effectiveness of bioremediation of hydrocarbon-contaminated environment is the application of biosurfactant producing microbes. In the present study, the biodegradation capacities of native bacterial consortia toward total petroleum hydrocarbons (TPH) with special emphasis to poly aromatic hydrocarbons were determined. The purpose of the study was to isolate TPH degrading bacterial strains from various petroleum contaminated soil of Assam, India and develop a robust bacterial consortium for bioremediation of crude oil of this native land. From a total of 23 bacterial isolates obtained from three different hydrocarbons contaminated samples five isolates, namely KS2, PG1, PG5, R1, and R2 were selected as efficient crude oil degraders with respect to their growth on crude oil enriched samples. Isolates KS2, PG1, and R2 are biosurfactant producers and PG5, R1 are non-producers. Fourteen different consortia were designed involving both biosurfactant producing and non-producing isolates. Consortium 10, which comprises two Bacillus strains namely, Bacillus pumilus KS2 and B. cereus R2 (identified by 16s rRNA sequencing) has shown the best result in the desired degradation of crude oil. The consortium showed degradation up to 84.15% of TPH after 5 weeks of incubation, as revealed from gravimetric analysis. FTIR (Fourier transform infrared) and GCMS (Gas chromatography-mass spectrometer) analyses were correlated with gravimetric data which reveals that the consortium has removed a wide range of petroleum hydrocarbons in comparison with abiotic control including different aliphatic and aromatic hydrocarbons.

  19. Analysis of the potential contamination risk of groundwater resources circulating in areas with anthropogenic activities

    Directory of Open Access Journals (Sweden)

    M. Spizzico

    2005-01-01

    Full Text Available The area investigated is located in the province of Brindisi (Italy. It is a generally flat area separated from the nearby carbonatic plateau of the Murgia by quite indistinct and high fault scarps. As regards the geological features, carbonatic basement rocks and post-cretaceous terrains made up of calabrian calcarenites and middle-upper Pleistocenic marine terraced deposits can be distinguished. In the examined area there are two different hydrogeological environments. The first is represented by deep groundwater, the main groundwater resource in Apulia. The second hydrogeological environment, now of lesser importance than the deep aquifer in terms of size and use, is made up of some small shallow groundwater systems situated in post-calabrian sands and located in the eastern area. During some sampling cycles carried out in the studied area, water was withdrawn from both the deep aquifer and from the shallow groundwater. For every sample, the necessary parameters were determined for the physical and chemical characterisation of two different hydrogeological environments. Moreover, some chemical parameters indicating anthropogenic activities were determined. Analysis of the aerial distribution of the measured parameters has shown some main areas subject to different conditions of contamination risk, in accordance with the hydrogeological and geological features of the investigated area. In the south-eastern part of the investigated area, the important action performed by the surface aquifer for protecting the deep groundwater from contamination of anthropogenic origin is clear. On the other hand, in the shallow groundwater, areas of nitrate and nitrite contamination have been identified, which result from the extensive use of fertilizers.

  20. Development of an efficient bacterial consortium for the potential remediation of hydrocarbons from contaminated sites

    Directory of Open Access Journals (Sweden)

    Kaustuvmani Patowary

    2016-07-01

    Full Text Available The intrinsic biodegradability of hydrocarbons and the distribution of proficient degrading microorganisms in the environment are very crucial for the implementation of bioremediation practices. Among others, one of the most favorable methods that can enhance the effectiveness of bioremediation of hydrocarbon-contaminated environment is the application of biosurfactant producing microbes. In the present study, the biodegradation capacities of native bacterial consortia towards total petroleum hydrocarbons (TPH with special emphasis to poly aromatic hydrocarbons (PAHs were determined. The purpose of the study was to isolate TPH degrading bacterial strains from various petroleum contaminated soil of Assam, India and develop a robust bacterial consortium for bioremediation of crude oil of this native land. From a total of 23 bacterial isolates obtained from three different hydrocarbons contaminated samples 5 isolates, namely KS2, PG1, PG5, R1 and R2 were selected as efficient crude oil degraders with respect to their growth on crude oil enriched samples. Isolates KS2, PG1 and R2 are biosurfactant producers and PG5, R1 are non-producers. Fourteen different consortia were designed involving both biosurfactant producing and non-producing isolates. Consortium 10, which comprises two Bacillus strains namely, Bacillus pumilus KS2 and Bacillus cereus R2 (identified by 16s rRNA sequencing has shown the best result in the desired degradation of crude oil. The consortium showed degradation up to 84.15% of total petroleum hydrocarbon (TPH after five weeks of incubation, as revealed from gravimetric analysis. FTIR (Fourier transform infrared and GCMS (Gas chromatography-mass spectrometer analyses were correlated with gravimetric data which reveals that the consortium has removed a wide range of petroleum hydrocarbons in comparison with abiotic control including different aliphatic and aromatic hydrocarbons.

  1. Mapping the environmental risk potential on surface water of pesticide contamination in the Prosecco's vineyard terraced landscape

    Science.gov (United States)

    Pizarro, Patricia; Ferrarese, Francesco; Loddo, Donato; Eugenio Pappalardo, Salvatore; Varotto, Mauro

    2016-04-01

    Intensive cropping systems today represent a paramount issue in terms of environmental impacts, since agricultural pollutants can constitute a potential threat to surface water, non-target organisms and aquatic ecosystems. Levels of pesticide concentrations in surface waters are indeed unquestionably correlated to crop and soil management practices at field-scale. Due to the numerous applications of pesticides required, orchards and vineyards can represent relevant non-point sources for pesticide contamination of water bodies, mainly prompted by soil erosion, surface runoff and spray drift. To reduce risks of pesticide contamination of surface water, the Directive 2009/128/CET imposed the local implementation of agricultural good practices and mitigation actions such as the use of vegetative buffer filter strips and hedgerows along river and pond banks. However, implementation of mitigation actions is often difficult, especially in extremely fragmented agricultural landscapes characterized by a complex territorial matrix set up on urban sprawling, frequent surface water bodies, important geomorphological processes and protected natural areas. Typically, such landscape matrix is well represented by the, Prosecco-DOCG vineyards area (NE of Italy, Province of Treviso) which lays on hogback hills of conglomerate, marls and sandstone that ranges between 50 and 500 m asl. Moreover such vineyards landscape is characterized by traditional and non-traditional agricultural terraces The general aim of this paper is to identify areas of surface water bodies with high potential risk of pesticide contamination from surrounding vineyards in the 735 ha of Lierza river basin (Refrontolo, TV), one of the most representative terraced landscape of the Prosecco-DOCG area. Specific aims are i) mapping terraced Prosecco-DOCG vineyards, ii) classifying potential risk from pesticide of the different areas. Remote sensing technologies such as four bands aerial photos (RGB+NIR) and Light

  2. Biogenic volatile organic compounds as a potential stimulator for organic contaminant degradation by soil microorganisms

    International Nuclear Information System (INIS)

    McLoughlin, Emma; Rhodes, Angela H.; Owen, Susan M.; Semple, Kirk T.

    2009-01-01

    The effects of monoterpenes on the degradation of 14 C-2,4-dichlorophenol (DCP) were investigated in soils collected from areas surrounding monoterpene and non-monoterpene-emitting vegetation. Indigenous microorganisms degraded 14 C-2,4-DCP to 14 CO 2 , after 1 d contact time. Degradation was enhanced by prior exposure of the soils to 2,4-DCP for 32 d, increasing extents of mineralisation up to 60%. Monoterpene amendments further enhanced 2,4-DCP degradation, but only following pre-exposure to both 2,4-DCP and monoterpene, with total 2,4-DCP mineralisation extents of up to 71%. Degradation was greatest at the higher monoterpene concentrations (≥1 μg kg -1 ). Total mineralisation extents were similar between concentrations, but higher than the control and the 0.1 μg kg -1 amendment, indicating that increases in monoterpene concentration has a diminishing enhancing effect. We suggest that monoterpenes can stimulate the biodegradation of 2,4-DCP by indigenous soil microorganisms and that monoterpene amendment in soils is an effective strategy for removing organic contaminants. - A amendment of soils with monoterpenes may induce organic contaminant degradation by indigenous soil microorganisms

  3. Phytoremediation potential of maize (Zea mays L.) in co-contaminated soils with pentachlorophenol and cadmium.

    Science.gov (United States)

    Hechmi, Nejla; Ben Aissa, Nadhira; Abdennaceur, Hassen; Jedidi, Naceur

    2013-01-01

    The ubiquitous coexistence of heavy metals and organic contaminants was increased in the polluted soil and phytoremediation as a remedial technology and management option is recommended to solve the problems of co-contamination. Growth of Zea mays L and pollutant removal ability may be influenced by interactions among mixed pollutants. Pot-culture experiments were conduced to investigate the single and interactive effect of cadmium (Cd) and pentachlorophenol (PCP) on growth of Zea mays L, PCP, and Cd removal from soil. Growth response of Zea mays L is considerably influenced by interaction of Cd and PCP, significantly declining with either Cd or PCP additions. The dissipation of PCP in soils was notably affected by interactions of Cd, PCP, and plant presence or absence. At the Pentachlorophenol in both planted and non-planted soil was greatly decreased at the end of the 10-week culture, accounting for 16-20% of initial extractable concentrations in non-planted soil and 9-14% in planted soil. With the increment of Cd level, residual pentachlorophenol in the planted soil tended to increase. The pentachlorophenol residual in the presence of high concentration of Cd was even higher in the planted soil than that in the non-planted soil.

  4. CyanoHAB occurrence and water irrigation cyanotoxin contamination: ecological impacts and potential health risks.

    Science.gov (United States)

    Saqrane, Sana; Oudra, Brahim

    2009-12-01

    The world-wide occurrence of harmful cyanobacteria blooms "CyanoHAB" in fresh and brackish waters creates problems for all life forms. During CyanoHAB events, toxic cyanobacteria produce cyanotoxins at high levels that can cause chronic and sub-chronic toxicities to animals, plants and humans. Cyanotoxicity in eukaryotes has been mainly focused on animals, but during these last years, data, related to cyanotoxin (mainly microcystins, MCs) impact on both aquatic and terrestrials crop plants irrigated by water containing these toxins, have become more and more available. This last cited fact is gaining importance since plants could in a direct or indirect manner contribute to cyanotoxin transfer through the food chain, and thus constitute a potent health risk source. The use of this contaminated irrigation water can also have an economical impact which appears by a reduction of the germination rate of seeds, and alteration of the quality and the productivity of crop plants. The main objective of this work was to discuss the eventual phytotoxicity of cyanotoxins (microcystins) as the major agricultural impacts induced by the use of contaminated water for plant irrigation. These investigations confirm the harmful effects (ecological, eco-physiological, socio-economical and sanitary risk) of dissolved MCs on agricultural plants. Thus, cyanotoxin phytotoxicity strongly suggests a need for the surveillance of CyanoHAB and the monitoring of water irrigation quality as well as for drinking water.

  5. Compressed-air power tools in orthopaedic surgery: exhaust air is a potential source of contamination.

    Science.gov (United States)

    Sagi, H C; DiPasquale, Thomas; Sanders, Roy; Herscovici, Dolfi

    2002-01-01

    To determine if the exhaust from surgical compressed-air power tools contains bacteria and if the exhaust leads to contamination of sterile surfaces. Bacteriologic study of orthopaedic power tools. Level I trauma center operative theater. None. Part I. Exhaust from two sterile compact air drills was sampled directly at the exhaust port. Part II. Exhaust from the drills was directed at sterile agar plates from varying distances. The agar plates represented sterile surfaces within the operative field. Part III. Control cultures. A battery-powered drill was operated over open agar plates in similar fashion as the compressed-air drills. Agar plates left open in the operative theater served as controls to rule out atmospheric contamination. Random cultures were taken from agar plates, gloves, drills, and hoses. Incidence of positive cultures. In Part I, all filters from both compressed-air drill exhausts were culture negative ( = 0.008). In Part II, the incidence of positive cultures for air drills number one and number two was 73% and 82%, respectively. The most commonly encountered organisms were, coagulase-negative Staphylococcus, and Micrococcus species. All control cultures from agar plates, battery-powered drill, gloves, and hoses were negative ( compressed-air power tools in orthopaedic surgery may contribute to the dissemination of bacteria onto the surgical field. We do not recommend the use of compressed-air power tools that do not have a contained exhaust.

  6. CyanoHAB Occurrence and Water Irrigation Cyanotoxin Contamination: Ecological Impacts and Potential Health Risks

    Science.gov (United States)

    Saqrane, Sana; Oudra, Brahim

    2009-01-01

    The world-wide occurrence of harmful cyanobacteria blooms “CyanoHAB” in fresh and brackish waters creates problems for all life forms. During CyanoHAB events, toxic cyanobacteria produce cyanotoxins at high levels that can cause chronic and sub-chronic toxicities to animals, plants and humans. Cyanotoxicity in eukaryotes has been mainly focused on animals, but during these last years, data, related to cyanotoxin (mainly microcystins, MCs) impact on both aquatic and terrestrials crop plants irrigated by water containing these toxins, have become more and more available. This last cited fact is gaining importance since plants could in a direct or indirect manner contribute to cyanotoxin transfer through the food chain, and thus constitute a potent health risk source. The use of this contaminated irrigation water can also have an economical impact which appears by a reduction of the germination rate of seeds, and alteration of the quality and the productivity of crop plants. The main objective of this work was to discuss the eventual phytotoxicity of cyanotoxins (microcystins) as the major agricultural impacts induced by the use of contaminated water for plant irrigation. These investigations confirm the harmful effects (ecological, eco-physiological, socio-economical and sanitary risk) of dissolved MCs on agricultural plants. Thus, cyanotoxin phytotoxicity strongly suggests a need for the surveillance of CyanoHAB and the monitoring of water irrigation quality as well as for drinking water. PMID:22069535

  7. Biodegradation of pentachloronitrobenzene by Cupriavidus sp. YNS-85 and its potential for remediation of contaminated soils.

    Science.gov (United States)

    Teng, Ying; Wang, Xiaomi; Zhu, Ye; Chen, Wei; Christie, Peter; Li, Zhengao; Luo, Yongming

    2017-04-01

    Pentachloronitrobenzene (PCNB) is a toxic chlorinated nitroaromatic compound. However, only a few bacteria have been reported to be able to utilize PCNB. In the present study, one pentachloronitrobenzene (PCNB)-degrading bacterium, Cupriavidus sp. YNS-85, was isolated from a contaminated Panax notoginseng plantation. The strain co-metabolized 200 mg L -1 PCNB in aqueous solution with a removal rate of 73.8% after 5 days. The bacterium also degraded PCNB effectively under acid conditions (pH 4-6) and showed resistance to toxic trace elements (arsenic, copper, and cadmium). Its ability to utilize proposed PCNB intermediates as sole carbon sources was also confirmed. The soil microcosm experiment further demonstrated that bacterial bioaugmentation enhanced the removal of PCNB (37.8%) from soil and the accumulation of pentachloroaniline (89.3%) after 30 days. Soil enzyme activity and microbial community functional diversity were positively influenced after bioremediation. These findings indicate that Cupriavidus sp. YNS-85 may be a suitable inoculant for in situ bioremediation of PCNB-polluted sites, especially those with acid soils co-contaminated with heavy metal(loid)s.

  8. Potential external contamination of pneumatic seed drills during sowing of dressed maize seeds.

    Science.gov (United States)

    Manzone, Marco; Balsari, Paolo; Marucco, Paolo; Tamagnone, Mario

    2016-07-01

    The use of pneumatic drills in maize cultivation causes dispersion in the atmosphere of some harmful substances normally used for dressing maize seeds. Some of the dust particles may be deposited on the machine's body, becoming dangerous for the environment and for operators. The aim of the present study was to analyse the amount of dust deposited on the frame of drills during maize sowing operations. Tests were performed with different drills and in different operating conditions. Data analysis showed that a significant amount (up to 30%) of the tracer can be deposited on the drill body. When wind was not present, higher quantities of tracer were collected and the forward speed did not influence significantly the tracer deposit on the seed drills. The use of different devices designed to prevent dust dispersion was able to limit up to 95% but was not able to eliminate the external contamination of the drill. The particles present on drills could become a problem for the operator during the filling of the drill. Additionally, the environment can be contaminated if pesticide remains on the drill, generating point-source pollution when the drill is parked outside. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  9. Arsenic-contaminated soils. Genetically modified Pseudomonas spp. and their arsenic-phytoremediation potential

    Energy Technology Data Exchange (ETDEWEB)

    Sizova, O.I.; Kochetkov, V.V.; Validov, S.Z.; Boronin, A.M. [Inst. of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Moscow (Russian Federation); Kosterin, P.V.; Lyubun, Y.V. [Inst. of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, Saratov (Russian Federation)

    2002-07-01

    Sorghum was inoculated with Pseudomonas bacteria, including strains harboring an As-resistance plasmid, pBS3031, to enhance As-extraction by the plants. Pseudomonas strains (P. fluorescens 38a, P. putida 53a, and P. aureofaciens BS1393) were chosen because they are antagonistic to a wide range of phytopathogenic fungi and bacteria, and they can stimulate plant growth. The resistance of natural rhizospheric pseudomonads to sodium arsenite was assessed. Genetically modified Pseudomonas strains resistant to As(III)/As(V) were obtained via conjugation or transformation. The effects of the strains on the growth of sorghum on sodium-arsenite-containing soils were assessed. The conclusions from this study are: (1) It is possible to increase the survivability of sorghum growing in sodium-arsenite-containing soil by using rhizosphere pseudomonads. (2) The presence of pBS3031 offers the strains a certain selective advantage in arsenite-contaminated soil. (3) The presence of pBS3031 impairs plant growth, due to the As-resistance mechanism determined by this plasmid: the transformation of the less toxic arsenate into the more toxic, plant-root-available arsenite by arsenate reductase and the active removal of arsenite from bacterial cells. (4) Such a mechanism makes it possible to develop a bacteria-assisted phytoremediation technology for the cleanup of As-contaminated soils and is the only possible way of removing the soil-sorbed arsenates from the environment. (orig.)

  10. The contaminant legacy from historic coastal landfills and their potential as sources of diffuse pollution.

    Science.gov (United States)

    O'Shea, Francis T; Cundy, Andrew B; Spencer, Kate L

    2018-03-01

    Prior to modern environmental regulation landfills in low-lying coastal environments were frequently constructed without leachate control, relying on natural attenuation within inter-tidal sediments to dilute and disperse contaminants reducing environmental impact. With sea level rise and coastal erosion these sites may now pose a pollution risk, yet have received little investigation. This work examines the extent of metal contamination in saltmarsh sediments surrounding a historic landfill in the UK. Patterns of sediment metal data suggest typical anthropogenic pollution chronologies for saltmarsh sediments in industrialised nations. However, many metals were also enriched at depth in close proximity to the landfill boundary and are indicative of a historical leachate plume. Though this total metal load is low, e.g., c. 1200 and 1650kg Pb and Zn respectively, with >1000 historic landfills on flood risk or eroding coastlines in the UK this could represent a significant, yet under-investigated, source of diffuse pollution. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Contaminated tooth brushes-potential threat to oral and general health

    Directory of Open Access Journals (Sweden)

    Rashmi Naik

    2015-01-01

    Full Text Available Background: Tooth brushing is most common method of maintaining oral hygiene. In removing plaque and other soft debris from the teeth, tooth brushes become contaminated with bacteria, blood, saliva and oral debris. These contaminated tooth brushes can be a source of infection. Aims and objectives: The aim of the present study was to evaluate the presence of microorganisms in the tooth brushes and to investigate the effect of disinfectants such as chlorhexidine gluconate, sodium hypochlorite and water to decontaminate them. Materials and Methods: Twenty-one children were asked to brush their teeth for 5 days with a tooth brush. The tooth brushes were put in Robertson′s Cooked Meat broth and were observed for growth of Streptococcal microorganisms. These tooth brushes were then placed in disinfectants such as 0.2% chlorhexidine gluconate (Group I, 1% sodium hypochlorite (Group II and water (Group III for 24 hrs and then cultured again. Reduction of growth of microorganisms was seen in Group I, Group II and remnants of growth seen in Group III. Conclusion: We conclude that the use of disinfectant for a tooth brush is a must for every individual at least at regular intervals.

  12. Hydrocarbon degradation potential in reference soils and soils contaminated with jet fuel

    International Nuclear Information System (INIS)

    Lee, R.F.; Hoeppel, R.

    1991-01-01

    Petroleum degradation in surface and subsurface soils is affected by such factors as moisture content, pH, soil type, soil organics, temperature, and oxygen concentrations. In this paper, the authors determine the degradation rates of 14 C-labeled hydrocarbons added to soils collected from a contaminated surface site, contaminated subsurface sites, and a clean reference site. The radiolabeled hydrocarbons used include benzene, toluene, naphthalene, 1-methynaphthalene, phenanthrene, fluorene, anthracene, chrysene, and hexadecane. Microbial degradation rates were based on determination of mineralization rates (production of 14 CO 2 ) of hydrocarbons that were added to soil samples. Since water was added and oxygen was not limiting, the hydrocarbon rates determined are likely to be higher than those occurring in situ. Using radiolabeled hydrocarbons, information can be provided on differences in the degradation rates of various petroleum compounds in different types of soils at a site, on possible production of petroleum metabolites in the soil, and on the importance of anaerobic petroleum degradation and the effects of nutrient, water, and surfactant addition on biodegradation rates

  13. Assessment of SRS radiological liquid and airborne contaminants and pathways

    International Nuclear Information System (INIS)

    Jannik, G.T.

    1997-04-01

    This report compiles and documents the radiological critical-contaminant/critical-pathway analysis performed for SRS. The analysis covers radiological releases to the atmosphere and to surface water, which are the principal media that carry contaminants off site. During routine operations at SRS, limited amounts of radionuclides are released to the environment through atmospheric and/or liquid pathways. These releases potentially result in exposure to offsite people. Though the groundwater beneath an estimated 5 to 10 percent of SRS has been contaminated by radionuclides, there is no evidence that groundwater contaminated with these constituents has migrated offsite (Arnett, 1996). Therefore, with the notable exception of radiological source terms originating from shallow surface water migration into site streams, onsite groundwater was not considered as a potential exposure pathway to offsite people

  14. Effect of Soil Aging on the Phytoremediation Potential of Zea mays in Chromium and Benzo[a]Pyrene Contaminated Soils.

    Science.gov (United States)

    Chigbo, Chibuike

    2015-06-01

    This study compared the phytoremediation potential of Zea mays in soil either aged or freshly amended with chromium (Cr) and benzo[a]pyrene (B[a]P). Z. mays showed increased shoot biomass in aged soils than in freshly spiked soils. The shoot biomass in contaminated soils increased by over 50% in aged soil when compared to freshly amended soils, and over 29% more Cr was accumulated in the shoot of Z. mays in aged soil than in freshly amended soil. Planting Z. mays in aged soil helped in the dissipation of more than 31% B[a]P than in freshly spiked soil, but in the absence of plants, there seemed to be no difference between the dissipation rates of B[a]P in freshly and aged co-contaminated soil. Z. mays seemed to enhance the simultaneous removal of Cr and B[a]P in aged soil than in freshly spiked soil and hence can be a good plant choice for phytoremediation of co-contaminated soils.

  15. Key decisions in a generic process for disposition of buildings that have actual or potential radiological contamination

    International Nuclear Information System (INIS)

    Spesard, A.; Donavan, K.; Bowden, B.; Crane, L.; Jensen, G.; Fox, K.L.; Goodwin, R.; Vandegrift, R.

    1997-01-01

    The Cleanup Standards Committee, formed within the Ohio Federal Facilities Forum, focuses on addressing issues related to cleanup levels and standards. To facilitate decision-making for the disposition of buildings that have potential or actual radiological contamination, the Cleanup Standards Committee developed a process to support building disposition decisions. This process is needed for two reasons: (1) due to changing missions, an increasing number of buildings on federal properties require disposition, and (2) current federal initiatives encourage the transfer of buildings and land for reuse and economic redevelopment. Since the committee developed this process using a teaming effort, the process reflects the experience, expertise, and opinions of committee members and other individuals with a broad range of experience and knowledge. The Generic Process for the Disposition of Buildings that have Potential or Actual Radiological Contamination is intended for use by Federal Facilities responsible for the cleanup of buildings at sites that have radiological process history. This process provides (1) a framework and supporting implementation guidelines for evaluating buildings that have actual or potential radiological contamination, and (2) a process for making building disposition decisions. This paper outlines on the key decision points and the associated data requirements of the process. Specifically, this paper focuses on the following decisions: Which decision-makers are appropriate to involve in the building disposition process; What is the preferred disposition of a building; What criteria are applicable for unconditional release; Is there sufficient existing information to proceed with disposition of a building; What level of survey is appropriate to determine and/or implement a preferred disposition of a building; and how are uncertainties addressed when implementing a building disposition

  16. Potential migration of buoyant LNAPL from intermediate level waste (ILW) emplaced in a geological disposal facility (GDF) for U.K. radioactive waste.

    Science.gov (United States)

    Benbow, Steven J; Rivett, Michael O; Chittenden, Neil; Herbert, Alan W; Watson, Sarah; Williams, Steve J; Norris, Simon

    2014-10-15

    A safety case for the disposal of Intermediate Level (radioactive) Waste (ILW) in a deep geological disposal facility (GDF) requires consideration of the potential for waste-derived light non-aqueous phase liquid (LNAPL) to migrate under positive buoyancy from disposed waste packages. Were entrainment of waste-derived radionuclides in LNAPL to occur, such migration could result in a shorter overall travel time to environmental or human receptors than radionuclide migration solely associated with the movement of groundwater. This paper provides a contribution to the assessment of this issue through multiphase-flow numerical modelling underpinned by a review of the UK's ILW inventory and literature to define the nature of the associated ILW LNAPL source term. Examination has been at the waste package-local GDF environment scale to determine whether proposed disposal of ILW would lead to significant likelihood of LNAPL migration, both from waste packages and from a GDF vault into the local host rock. Our review and numerical modelling support the proposition that the release of a discrete free phase LNAPL from ILW would not present a significant challenge to the safety case even with conservative approximations. 'As-disposed' LNAPL emplaced with the waste is not expected to pose a significant issue. 'Secondary LNAPL' generated in situ within the disposed ILW, arising from the decomposition of plastics, in particular PVC (polyvinyl chloride), could form the predominant LNAPL source term. Released high molecular weight phthalate plasticizers are judged to be the primary LNAPL potentially generated. These are expected to have low buoyancy-based mobility due to their very low density contrast with water and high viscosity. Due to the inherent uncertainties, significant conservatisms were adopted within the numerical modelling approach, including: the simulation of a deliberately high organic material--PVC content wastestream (2D03) within an annular grouted waste package

  17. Vertical distribution of dehalogenating bacteria in mangrove sediment and their potential to remove polybrominated diphenyl ether contamination.

    Science.gov (United States)

    Pan, Ying; Chen, Juan; Zhou, Haichao; Farzana, Shazia; Tam, Nora F Y

    2017-11-30

    The removal and degradation of polybrominated diphenyl ethers (PBDEs) in sediments are not clear. The vertical distribution of total and dehalogenating bacteria in sediment cores collected from a typical mangrove swamp in South China and their intrinsic degradation potential were investigated. These bacterial groups had the highest abundances in surface sediments (0-5cm). A 5-months microcosm experiment also showed that surface sediments had the highest rate to remove BDE-47 than deeper sediments (5-30cm) under anaerobic condition. The deeper sediments, being more anaerobic, had lower population of dehalogenating bacteria leading to a weaker BDE-47 removal potential than surface sediments. Stepwise multiple regression analysis indicated that Dehalococcoides spp. were the most important dehalogenating bacteria affecting the anaerobic removal of BDE-47 in mangrove sediments. This is the first study reporting that mangrove sediments harbored diverse groups of dehalogenating bacteria and had intrinsic potential to remove PBDE contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Potentially toxic contamination of sediments, water and two animal species in Lake Kalimanci, FYR Macedonia: Relevance to human health

    International Nuclear Information System (INIS)

    Vrhovnik, Petra; Arrebola, Juan P.; Serafimovski, Todor; Dolenec, Tadej; Šmuc, Nastja Rogan; Dolenec, Matej; Mutch, Elaine

    2013-01-01

    The objectives of the research were: (1) to examine the concentrations of metals in Vimba melanops and Rana temporaria and (2) to evaluate the potential risks of the contaminated organisms to human health in Makedonska Kamenica region. Analyses identified high levels of Cr, Hg, Ni and Pb in studied animals, which also exceeded their permissible levels in food. In sediment and soil samples, levels of Cd, Cu, Cr, Pb, Zn and As were perceived, while Cd, Cu, Ni, Pb, Se and As were increased in water samples. Results of transfer factor revealed that the examined animals had higher bioaccumulation rate from surrounding waters than from sediments or soils. The accomplished Health Risk Index disclosed that studied animals can have considerably high health risks for inhabitants. Conclusively, they could be considered as highly contaminated with metals and can consequently harm human health, especially children in their early development stages. -- Highlights: •The study merges the accumulation of PTE in animal species, sediments, soils and water. •Correlation between different media and their impact to living organisms'. •Considerably high health risks for inhabitants. -- In the Makedonska Kamenica region had been described several potential sources of exposure therefore exists the potential threat to human health

  19. Bacterial Diversity and Bioremediation Potential of the Highly Contaminated Marine Sediments at El-Max District (Egypt, Mediterranean Sea)

    KAUST Repository

    Amer, Ranya A.

    2015-02-01

    Coastal environments worldwide are threatened by the effects of pollution, a risk particularly high in semienclosed basins like the Mediterranean Sea that is poorly studied from bioremediation potential perspective especially in the Southern coast. Here, we investigated the physical, chemical, and microbiological features of hydrocarbon and heavy metals contaminated sediments collected at El-Max bay (Egypt). Molecular and statistical approaches assessing the structure of the sediment-dwelling bacterial communities showed correlations between the composition of bacterial assemblages and the associated environmental parameters. Fifty strains were isolated on mineral media supplemented by 1% crude oil and identified as a diverse range of hydrocarbon-degrading bacteria involved in different successional stages of biodegradation. We screened the collection for biotechnological potential studying biosurfactant production, biofilm formation, and the capability to utilize different hydrocarbons. Some strains were able to grow on multiple hydrocarbons as unique carbon source and presented biosurfactant-like activities and/or capacity to form biofilm and owned genes involved in different detoxification/degradation processes. El-Max sediments represent a promising reservoir of novel bacterial strains adapted to high hydrocarbon contamination loads. The potential of the strains for exploitation for in situ intervention to combat pollution in coastal areas is discussed.

  20. Endocrine-Disrupting Chemicals and Oil and Natural Gas Operations: Potential Environmental Contamination and Recommendations to Assess Complex Environmental Mixtures.

    Science.gov (United States)

    Kassotis, Christopher D; Tillitt, Donald E; Lin, Chung-Ho; McElroy, Jane A; Nagel, Susan C

    2016-03-01

    Hydraulic fracturing technologies, developed over the last 65 years, have only recently been combined with horizontal drilling to unlock oil and gas reserves previously deemed inaccessible. Although these technologies have dramatically increased domestic oil and natural gas production, they have also raised concerns for the potential contamination of local water supplies with the approximately 1,000 chemicals that are used throughout the process, including many known or suspected endocrine-disrupting chemicals. We discuss the need for an endocrine component to health assessments for drilling-dense regions in the context of hormonal and antihormonal activities for chemicals used. We discuss the literature on a) surface and groundwater contamination by oil and gas extraction operations, and b) potential human exposure, particularly in the context of the total hormonal and antihormonal activities present in surface and groundwater from natural and anthropogenic sources; we also discuss initial analytical results and critical knowledge gaps. In light of the potential for environmental release of oil and gas chemicals that can disrupt hormone receptor systems, we recommend methods for assessing complex hormonally active environmental mixtures. We describe a need for an endocrine-centric component for overall health assessments and provide information supporting the idea that using such a component will help explain reported adverse health trends as well as help develop recommendations for environmental impact assessments and monitoring programs.

  1. Evaluation of trace organic contaminants in ultra-pure water production processes by measuring total organic halogen formation potential

    International Nuclear Information System (INIS)

    Urano, Kohei; Iwase, Yoko

    1984-01-01

    A new procedure for the determination of organic substances in water with high accuracy and high sensitivity was proposed, in which a hypochlorite is added to water, and the resultant total amount of organic halogen compounds (TOX formation potential) was measured, and it was applied to the evaluation of trace organic contaminants in ultra-pure water production process. In this investigation, the TOX formation potential of the raw water which was to be used for the ultra-pure water production process, intermediately treated water and ultra-pure water was measured to clarify the behavior of organic substances in the ultra-pure water production process and to demonstrate the usefulness of this procedure to evaluate trace organic contaminants in water. The measurement of TOX formation potential requires no specific technical skill, and only a short time, and gives accurate results, therefore, it is expected that the water quality control in the ultra-pure water production process can be performed more exactly by applying this procedure. (Yoshitake, I.)

  2. Bacterial Diversity and Bioremediation Potential of the Highly Contaminated Marine Sediments at El-Max District (Egypt, Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Ranya A. Amer

    2015-01-01

    Full Text Available Coastal environments worldwide are threatened by the effects of pollution, a risk particularly high in semienclosed basins like the Mediterranean Sea that is poorly studied from bioremediation potential perspective especially in the Southern coast. Here, we investigated the physical, chemical, and microbiological features of hydrocarbon and heavy metals contaminated sediments collected at El-Max bay (Egypt. Molecular and statistical approaches assessing the structure of the sediment-dwelling bacterial communities showed correlations between the composition of bacterial assemblages and the associated environmental parameters. Fifty strains were isolated on mineral media supplemented by 1% crude oil and identified as a diverse range of hydrocarbon-degrading bacteria involved in different successional stages of biodegradation. We screened the collection for biotechnological potential studying biosurfactant production, biofilm formation, and the capability to utilize different hydrocarbons. Some strains were able to grow on multiple hydrocarbons as unique carbon source and presented biosurfactant-like activities and/or capacity to form biofilm and owned genes involved in different detoxification/degradation processes. El-Max sediments represent a promising reservoir of novel bacterial strains adapted to high hydrocarbon contamination loads. The potential of the strains for exploitation for in situ intervention to combat pollution in coastal areas is discussed.

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

    Directory of Open Access Journals (Sweden)

    Tongchai Thitiphuree

    2013-01-01

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

  4. Bacterial Diversity and Bioremediation Potential of the Highly Contaminated Marine Sediments at El-Max District (Egypt, Mediterranean Sea)

    Science.gov (United States)

    Amer, Ranya A.; El Gendi, Hamada M.; Goda, Doaa A.; Corsini, Anna; Cavalca, Lucia; Fusi, Marco; Daffonchio, Daniele; Abdel-Fattah, Yasser R.

    2015-01-01

    Coastal environments worldwide are threatened by the effects of pollution, a risk particularly high in semienclosed basins like the Mediterranean Sea that is poorly studied from bioremediation potential perspective especially in the Southern coast. Here, we investigated the physical, chemical, and microbiological features of hydrocarbon and heavy metals contaminated sediments collected at El-Max bay (Egypt). Molecular and statistical approaches assessing the structure of the sediment-dwelling bacterial communities showed correlations between the composition of bacterial assemblages and the associated environmental parameters. Fifty strains were isolated on mineral media supplemented by 1% crude oil and identified as a diverse range of hydrocarbon-degrading bacteria involved in different successional stages of biodegradation. We screened the collection for biotechnological potential studying biosurfactant production, biofilm formation, and the capability to utilize different hydrocarbons. Some strains were able to grow on multiple hydrocarbons as unique carbon source and presented biosurfactant-like activities and/or capacity to form biofilm and owned genes involved in different detoxification/degradation processes. El-Max sediments represent a promising reservoir of novel bacterial strains adapted to high hydrocarbon contamination loads. The potential of the strains for exploitation for in situ intervention to combat pollution in coastal areas is discussed. PMID:26273661

  5. Endocrine-disrupting chemicals and oil and natural gas operations: Potential environmental contamination and recommendations to assess complex environmental mixtures

    Science.gov (United States)

    Kassotis, Christopher D.; Tillitt, Donald E.; Lin, Chung-Ho; McElroy, Jane A.; Nagel, Susan C.

    2016-01-01

    Background: Hydraulic fracturing technologies, developed over the last 65 years, have only recently been combined with horizontal drilling to unlock oil and gas reserves previously deemed inaccessible. While these technologies have dramatically increased domestic oil and natural gas production, they have also raised concerns for the potential contamination of local water supplies with the approximately 1,000 chemicals used throughout the process, including many known or suspected endocrine-disrupting chemicals.Objectives: We discuss the need for an endocrine component to health assessments for drilling-dense regions in the context of hormonal and anti-hormonal activities for chemicals used.Methods: We discuss the literature on 1) surface and ground water contamination by oil and gas extraction operations, and 2) potential human exposure, particularly in context of the total hormonal and anti-hormonal activities present in surface and ground water from natural and anthropogenic sources, with initial analytical results and critical knowledge gaps discussed.Discussion: In light of the potential for environmental release of oil and gas chemicals that can disrupt hormone receptor systems, we recommend methods for assessing complex hormonally active environmental mixtures.Conclusions: We describe a need for an endocrine-centric component for overall health assessments and provide supporting information that using this may help explain reported adverse health trends as well as help develop recommendations for environmental impact assessments and monitoring programs.

  6. Evaluation the Growth Potential of Artichoke (Synara scolymus L. and Milk thistle (Sylibum marianum L. in Petroleum-contaminated Soil

    Directory of Open Access Journals (Sweden)

    Sahar Zamani

    2018-04-01

    Full Text Available Petroleum hydrocarbons are one of the most common pollutants groups in the environment and threaten the human, animals and plants health. Phytoremediation is a method for cleaning the contaminated areas. Medicinal plants because of their defense mechanisms able to resist and thwart destructive effect of stressors. Some plants have better resistance, including Artichoke (Cynara scolymus L. and Milk Thistle (Silybum marianum L.; from Asteraceae family that has polyphenolic compounds with antioxidant properties and hepatoprotectors. To evaluation the growth potential of Artichoke and Milk Thistle in petroleum-contaminated soil, an experiment in a completely randomized design was done with 6 levels of gas oil and 3 replications in Gorgan University of Agricultural Sciences and Natural Resources. The results showed that, gas oil hydrocarbon had a significant effect at %1 on germination percent of seed and indexes involved in seedling growth including plant height, length, and width, fresh and dry weight of artichoke leaf. In Milk Thistle, gas oil had no significant effect on germination percent. Opposite to that, significant effect at %1 on growth indexes was observed. The maximum germination percent in Artichoke and Milk Thistle seeds was observed in 20 and 10 g/kg gas oil, respectively and the minimum of germination percent was observed in seeds samples that treated with 80 g gas oil per kg soil. Artichoke seedlings were more tolerance than Milk Thistle to the contaminated soil as better growth was observed in this condition. Generally, it seems that these two valuable medicinal plants had relatively resistance to the gas oli pollution and are suggestible to use in oil contaminated soil for cleaning purpose

  7. Fenpropathrin biodegradation pathway in Bacillus sp. DG-02 and its potential for bioremediation of pyrethroid-contaminated soils.

    Science.gov (United States)

    Chen, Shaohua; Chang, Changqing; Deng, Yinyue; An, Shuwen; Dong, Yi Hu; Zhou, Jianuan; Hu, Meiying; Zhong, Guohua; Zhang, Lian-Hui

    2014-03-12

    The widely used insecticide fenpropathrin in agriculture has become a public concern because of its heavy environmental contamination and toxic effects on mammals, yet little is known about the kinetic and metabolic behaviors of this pesticide. This study reports the degradation kinetics and metabolic pathway of fenpropathrin in Bacillus sp. DG-02, previously isolated from the pyrethroid-manufacturing wastewater treatment system. Up to 93.3% of 50 mg L(-1) fenpropathrin was degraded by Bacillus sp. DG-02 within 72 h, and the degradation rate parameters qmax, Ks, and Ki were determined to be 0.05 h(-1), 9.0 mg L(-1), and 694.8 mg L(-1), respectively. Analysis of the degradation products by gas chromatography-mass spectrometry led to identification of seven metabolites of fenpropathrin, which suggest that fenpropathrin could be degraded first by cleavage of its carboxylester linkage and diaryl bond, followed by degradation of the aromatic ring and subsequent metabolism. In addition to degradation of fenpropathrin, this strain was also found to be capable of degrading a wide range of synthetic pyrethroids including deltamethrin, λ-cyhalothrin, β-cypermethrin, β-cyfluthrin, bifenthrin, and permethrin, which are also widely used insecticides with environmental contamination problems with the degradation process following the first-order kinetic model. Bioaugmentation of fenpropathrin-contaminated soils with strain DG-02 significantly enhanced the disappearance rate of fenpropathrin, and its half-life was sharply reduced in the soils. Taken together, these results depict the biodegradation mechanisms of fenpropathrin and also highlight the promising potentials of Bacillus sp. DG-02 in bioremediation of pyrethroid-contaminated soils.

  8. Toxicological Benchmarks for Screening Potential Contaminants of Concern for Effects on Soil and Litter Invertebrates and Heterotrophic Process

    Energy Technology Data Exchange (ETDEWEB)

    Will, M.E.

    1994-01-01

    This report presents a standard method for deriving benchmarks for the purpose of ''contaminant screening,'' performed by comparing measured ambient concentrations of chemicals. The work was performed under Work Breakdown Structure 1.4.12.2.3.04.07.02 (Activity Data Sheet 8304). In addition, this report presents sets of data concerning the effects of chemicals in soil on invertebrates and soil microbial processes, benchmarks for chemicals potentially associated with United States Department of Energy sites, and literature describing the experiments from which data were drawn for benchmark derivation.

  9. Present and potential contamination of the river system at Mayak PA

    International Nuclear Information System (INIS)

    Amundsen, I.; Strand, P.; Malyshev, S.V.

    1999-01-01

    Studies of mobility of radionuclides in environmental samples at Mayak show that strontium-90 is the most mobile of the relevant radionuclides and hence can be transported by river water. Cesium-137, although less mobile, can also be transported over large distances. The main source of river contamination today is the remobilization of strontium-90 from the boggy area at the upper reaches of Techa River (Asanov Swamp). Regular Russian monitoring programmes show that levels of strontium-90 leaving the swamp are three times higher than levels entering the swamp. The net outflow from the Swamp is now estimated to 2-3% of the 37 TBq of strontium-90 located in the swamp, 1992 levels

  10. Modeling dynamics of {sup 137}Cs in forest surface environments: Application to a contaminated forest site near Fukushima and assessment of potential impacts of soil organic matter interactions

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Masakazu, E-mail: ohta.masakazu@jaea.go.jp; Nagai, Haruyasu; Koarashi, Jun

    2016-05-01

    A process-based model for {sup 137}Cs transfer in forest surface environments was developed to assess the dynamic behavior of Fukushima-derived {sup 137}Cs in a Japanese forest. The model simulation successfully reproduced the observed data from 3 year migration of {sup 137}Cs in the organic and mineral soil layers at a contaminated forest near Fukushima. The migration of {sup 137}Cs from the organic layer to the mineral soil was explained by the direct deposition pattern on the forest floor and the turnover of litter materials in the organic layer under certain ecological conditions. Long-term predictions indicated that more than 90% of the deposited {sup 137}Cs would remain within the top 5 cm of the soil for up to 30 years after the accident, suggesting that the forest acts as an effective long-term reservoir of {sup 137}Cs with limited transfer via the groundwater pathway. The model was also used to explore the potential impacts of soil organic matter (SOM) interactions on the mobility and bioavailability of {sup 137}Cs in the soil–plant system. The simulation results for hypothetical organic soils with modified parameters of {sup 137}Cs turnover revealed that the SOM-induced reduction of {sup 137}Cs adsorption elevates the fraction of dissolved {sup 137}Cs in the soil solution, thereby increasing the soil-to-plant transfer of {sup 137}Cs without substantially altering the fractional distribution of {sup 137}Cs in the soil. Slower fixation of {sup 137}Cs on the flayed edge site of clay minerals and enhanced mobilization of the clay-fixed {sup 137}Cs in organic-rich soils also appeared to elevate the soil-to-plant transfer of {sup 137}Cs by increasing the fraction of the soil-adsorbed (exchangeable) {sup 137}Cs. A substantial proportion (approximate 30%–60%) of {sup 137}Cs in these organic-rich soils was transferred to layers deeper than 5 cm decades later. These results suggested that SOM influences the behavior of {sup 137}Cs in forests over a prolonged

  11. [Immobilization remediation of Cd and Pb contaminated soil: remediation potential and soil environmental quality].

    Science.gov (United States)

    Sun, Yue-Bing; Wang, Peng-Chao; Xu, Ying-Ming; Sun, Yang; Qin, Xu; Zhao, Li-Jie; Wang, Lin; Liang, Xue-Feng

    2014-12-01

    A pot experiment was conducted to investigate the immobilization remediation effects of sepiolite on soils artificially combined contamination by Cd and Pb using a set of various pH and speciation of Cd and Pb in soil, heavy metal concentration in Oryza sativa L., and soil enzyme activity and microbial quantity. Results showed that the addition of sepiolite increased the soil pH, and the exchangeable fraction of heavy metals was converted into Fe-Mn oxide, organic and residual forms, the concentration of exchangeable form of Cd and Pb reduced by 1.4% - 72.9% and 11.8% - 51.4%, respectively, when compared with the control. The contents of heavy metals decreased with increasing sepiolite, with the maximal Cd reduction of 39.8%, 36.4%, 55.2% and 32.4%, respectively, and 22.1%, 54.6%, 43.5% and 17.8% for Pb, respectively, in the stems, leaves, brown rice and husk in contrast to CK. The addition of sepiolite could improve the soil environmental quality, the catalase and urease activities and the amount of bacteria and actinomycete were increased to some extents. Although the fungi number and invertase activity were inhibited compared with the control group, it was not significantly different (P > 0.05). The significant correlation between pH, available heavy metal content, urease and invertase activities and heavy metal concentration in the plants indicated that these parameters could be used to evaluate the effectiveness of stabilization remediation of heavy metal contaminated soil.

  12. Zeb1 Is a Potential Regulator of Six2 in the Proliferation, Apoptosis and Migration of Metanephric Mesenchyme Cells

    Directory of Open Access Journals (Sweden)

    Yuping Gu

    2016-08-01

    Full Text Available Nephron progenitor cells surround around the ureteric bud tips (UB and inductively interact with the UB to originate nephrons, the basic units of renal function. This process is determined by the internal balance between self-renewal and consumption of the nephron progenitor cells, which is depending on the complicated regulation networks. It has been reported that Zeb1 regulates the proliferation of mesenchymal cells in mouse embryos. However, the role of Zeb1 in nephrons generation is not clear, especially in metanephric mesenchyme (MM. Here, we detected cell proliferation, apoptosis and migration in MM cells by EdU assay, flow cytometry assay and wound healing assay, respectively. Meanwhile, Western and RT-PCR were used to measure the expression level of Zeb1 and Six2 in MM cells and developing kidney. Besides, the dual-luciferase assay was conducted to study the molecular relationship between Zeb1 and Six2. We found that knock-down of Zeb1 decreased cell proliferation, migration and promoted cell apoptosis in MM cells and Zeb1 overexpression leaded to the opposite data. Western-blot and RT-PCR results showed that knock-down of Zeb1 decreased the expression of Six2 in MM cells and Zeb1 overexpression contributed to the opposite results. Similarly, Zeb1 promoted Six2 promoter reporter activity in luciferase assays. However, double knock-down of Zeb1 and Six2 did not enhance the apoptosis of MM cells compared with control cells. Nevertheless, double silence of Zeb1 and Six2 repressed cell proliferation. In addition, we also found that Zeb1 and Six2 had an identical pattern in distinct developing phases of embryonic kidney. These results indicated that there may exist a complicated regulation network between Six2 and Zeb1. Together, we demonstrate Zeb1 promotes proliferation and apoptosis and inhibits the migration of MM cells, in association with Six2.

  13. Zeb1 Is a Potential Regulator of Six2 in the Proliferation, Apoptosis and Migration of Metanephric Mesenchyme Cells

    Science.gov (United States)

    Gu, Yuping; Zhao, Ya; Zhou, Yuru; Xie, Yajun; Ju, Pan; Long, Yaoshui; Liu, Jianing; Ni, Dongsheng; Cao, Fen; Lyu, Zhongshi; Mao, Zhaomin; Hao, Jin; Li, Yiman; Wan, Qianya; Kanyomse, Quist; Liu, Yamin; Ren, Die; Ning, Yating; Li, Xiaofeng; Zhou, Qin; Li, Bing

    2016-01-01

    Nephron progenitor cells surround around the ureteric bud tips (UB) and inductively interact with the UB to originate nephrons, the basic units of renal function. This process is determined by the internal balance between self-renewal and consumption of the nephron progenitor cells, which is depending on the complicated regulation networks. It has been reported that Zeb1 regulates the proliferation of mesenchymal cells in mouse embryos. However, the role of Zeb1 in nephrons generation is not clear, especially in metanephric mesenchyme (MM). Here, we detected cell proliferation, apoptosis and migration in MM cells by EdU assay, flow cytometry assay and wound healing assay, respectively. Meanwhile, Western and RT-PCR were used to measure the expression level of Zeb1 and Six2 in MM cells and developing kidney. Besides, the dual-luciferase assay was conducted to study the molecular relationship between Zeb1 and Six2. We found that knock-down of Zeb1 decreased cell proliferation, migration and promoted cell apoptosis in MM cells and Zeb1 overexpression leaded to the opposite data. Western-blot and RT-PCR results showed that knock-down of Zeb1 decreased the expression of Six2 in MM cells and Zeb1 overexpression contributed to the opposite results. Similarly, Zeb1 promoted Six2 promoter reporter activity in luciferase assays. However, double knock-down of Zeb1 and Six2 did not enhance the apoptosis of MM cells compared with control cells. Nevertheless, double silence of Zeb1 and Six2 repressed cell proliferation. In addition, we also found that Zeb1 and Six2 had an identical pattern in distinct developing phases of embryonic kidney. These results indicated that there may exist a complicated regulation network between Six2 and Zeb1. Together, we demonstrate Zeb1 promotes proliferation and apoptosis and inhibits the migration of MM cells, in association with Six2. PMID:27509493

  14. Specific features of 137Cs migration and accumulation in chernozem soils of forest ecosystems in the zone contaminated due to the Chornobyl accident

    International Nuclear Information System (INIS)

    Tsvetnova, O.B.; Shcheglov, A.I.; Orlov, A.A.

    2005-01-01

    A number of factors influencing 137 Cs fate and biological availability in chernozem soils under the forest vegetation were assessed for various climatic zones. The migration rates of 137 Cs in the profile of chernozem soils were shown to depend primary on forest litter composition and structure. In the absence of forest litter the soil mineralogical composition and humus content become the most influential factors of caesium mobility

  15. In vitro migration and proliferation ("wound healing") potential of mesenchymal stromal cells generated from human CD271(+) bone marrow mononuclear cells.

    Science.gov (United States)

    Latifi-Pupovci, Hatixhe; Kuçi, Zyrafete; Wehner, Sibylle; Bönig, Halvard; Lieberz, Ralf; Klingebiel, Thomas; Bader, Peter; Kuçi, Selim

    2015-09-25

    Emerging evidence indicates that mesenchymal stromal cells (MSCs) isolated from different tissue sources may be used in vivo as tissue restorative agents. To date, there is no evidence, however, on migration and proliferation ("wound healing") potential of different subsets of MSCs. The main goal of this study was therefore to compare the in vitro "wound healing" capacity of MSCs generated from positively selected CD271(+) bone marrow mononuclear cells (CD271-MSCs) and MSCs generated by plastic adherence (PA-MSCs). The in vitro model of wound healing (CytoSelect™ 24-Well Wound Healing Assay) was used in order to compare the migration and proliferation potential of CD271-MSCs and PA-MSCs of passage 2 and 4 cultured in presence or absence of growth factors or cytokines. CD271-MSCs of both passages when compared to PA-MSCs demonstrated a significantly higher potential to close the wound 12 and 24 h after initiation of the wound healing assay (P MSCs of second passage was significantly improved after stimulation with FGF-2 (P MSCs of P4 12 h after the treatment (P MSCs of both passages with growth factors or cytokines did not affect their migratory potential. Our in vitro data provide the first evidence that CD271-MSCs are significantly more potent in "wound healing" than their counterparts PA-MSCs.

  16. The Influence of Drainage Wells Barrier on Reducing the Amount of Major Contaminants Migrating from a Very Large Mine Tailings Disposal Site

    Directory of Open Access Journals (Sweden)

    Duda Robert

    2014-12-01

    its foreground. The efficiency of groundwater protection was determined on the basis of a new approach. In applied method the loads of characteristic and commonly recognizable compounds, i.e. salt (NaCl and gypsum (CaSO4 were calculated, instead their chemical components. The temporal and spatial variability of captured main contaminants loads as well as its causes are discussed. The paper ends with the results of efficiency analyses of the barrier and with respect to the predicted increase in contaminant concentrations in the pulp poured out to the tailings site.

  17. Potential effects of hydroelectric dam development in the Mekong River basin on the migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus) elucidated by otolith microchemistry.

    Science.gov (United States)

    Fukushima, Michio; Jutagate, Tuantong; Grudpan, Chaiwut; Phomikong, Pisit; Nohara, Seiichi

    2014-01-01

    The migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus), two of the most economically important fish species in the Mekong River, was studied using an otolith microchemistry technique. Fish and river water samples were collected in seven regions throughout the whole basin in Thailand, Laos and Cambodia over a 4 year study period. There was coherence between the elements in the ambient water and on the surface of the otoliths, with strontium (Sr) and barium (Ba) showing the strongest correlation. The partition coefficients were 0.409-0.496 for Sr and 0.055 for Ba. Otolith Sr-Ba profiles indicated extensive synchronized migrations with similar natal origins among individuals within the same region. H. siamensis movement has been severely suppressed in a tributary system where a series of irrigation dams has blocked their migration. H. lobatus collected both below and above the Khone Falls in the mainstream Mekong exhibited statistically different otolith surface elemental signatures but similar core elemental signatures. This result suggests a population originating from a single natal origin but bypassing the waterfalls through a passable side channel where a major hydroelectric dam is planned. The potential effects of damming in the Mekong River are discussed.

  18. Potential effects of hydroelectric dam development in the Mekong River basin on the migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus elucidated by otolith microchemistry.

    Directory of Open Access Journals (Sweden)

    Michio Fukushima

    Full Text Available The migration of Siamese mud carp (Henicorhynchus siamensis and H. lobatus, two of the most economically important fish species in the Mekong River, was studied using an otolith microchemistry technique. Fish and river water samples were collected in seven regions throughout the whole basin in Thailand, Laos and Cambodia over a 4 year study period. There was coherence between the elements in the ambient water and on the surface of the otoliths, with strontium (Sr and barium (Ba showing the strongest correlation. The partition coefficients were 0.409-0.496 for Sr and 0.055 for Ba. Otolith Sr-Ba profiles indicated extensive synchronized migrations with similar natal origins among individuals within the same region. H. siamensis movement has been severely suppressed in a tributary system where a series of irrigation dams has blocked their migration. H. lobatus collected both below and above the Khone Falls in the mainstream Mekong exhibited statistically different otolith surface elemental signatures but similar core elemental signatures. This result suggests a population originating from a single natal origin but bypassing the waterfalls through a passable side channel where a major hydroelectric dam is planned. The potential effects of damming in the Mekong River are discussed.

  19. microRNA-494 is a potential prognostic marker and inhibits cellular proliferation, migration and invasion by targeting SIRT1 in epithelial ovarian cancer.

    Science.gov (United States)

    Yang, Aijun; Wang, Xuenan; Yu, Chunna; Jin, Zhenzhen; Wei, Lingxia; Cao, Jinghe; Wang, Qin; Zhang, Min; Zhang, Lin; Zhang, Lei; Hao, Cuifang

    2017-09-01

    Ovarian cancer is one of the most common types of gynecological malignancy worldwide, and is the fourth leading cause of cancer-associated mortality among women. Despite improvements in therapeutic treatments, the prognosis for epithelial ovarian cancer (EOC) remains poor, mainly due to the rapid growth and metastasis of ovarian cancer tumors. An increasing number of studies have indicated that microRNAs (miRNAs) are involved in the carcinogenesis and progression of human cancer, suggesting that miRNAs may be used in clinical prognosis and as a therapeutic target in EOC. The aim of the present study was to investigate the expression levels of miRNA-494 in EOC tissues and cell lines. The clinical significance of miRNA-494 in patients with EOC was also evaluated. The results demonstrated that miRNA-494 was significantly downregulated in EOC tissues and cell lines. Low expression levels of miRNA-494 were associated with poor prognostic features, including International Federation of Gynecology and Obstetrics stage, tumor size and lymph node metastasis. In vitro functional studies demonstrated that overexpression of miRNA-494 inhibited proliferation, migration and invasion in EOC cells. By contrast, knockdown of miRNA-494 enhanced cell growth, migration and invasion in EOC cells. Notably, sirtuin 1 (SIRT1) was identified as a direct target of miRNA-494 in EOC. Furthermore, MTT, cell migration and invasion assays verified that EOC cell proliferation, migration and invasion were completely restored with forced miRNA-494 expression and SIRT1 restoration. Together, these findings suggest that miRNA-494 is a potential prognostic marker, and may provide novel therapeutic regimens of targeted therapy for EOC.

  20. Hydrology of the solid waste burial ground as related to potential migration of radionuclides, Idaho National Engineering Laboratory

    Science.gov (United States)

    Barraclough, Jack T.; Robertson, J.B.; Janzer, V.J.; Saindon, L.G.

    1976-01-01

    A study was made (1970-1974) to evaluate the geohydrologic and geochemical controls on subsurface migration of radionuclides from pits and trenches in the Idaho National Engineering Laboratory (INEL) solid waste burial ground and to determine the existence and extent of radionuclide migration from the burial ground. A total of about 1,700 sediment, rock, and water samples were collected from 10 observation wells drilled in and near the burial ground of Idaho National Engineering Laboratory, formerly the National Reactor Testing Station (NRTS). Within the burial ground area, the subsurface rocks are composed principally of basalt. Wind- and water-deposited sediments occur at the surface and in beds between the thicker basalt zones. Two principal sediment beds occur at about 110 feet and 240 feet below the land surface. The average thickness of the surficial sedimentary layer is about 15 feet while that of the two principal subsurface layers is 13 and 14 feet, respectively. The water table in the aquifer beneath the burial ground is at a depth of about 580 feet. Fission, activation, and transuranic elements were detected in some of the samples from the 110- and 240-foot sedimentary layers. (Woodard-USGS)

  1. 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).

  2. Preliminary description of hydrologic characteristics and contaminant transport potential of rocks in the Pasco Basin, south-central Washington

    International Nuclear Information System (INIS)

    Deju, R.A.; Fecht, K.R.

    1979-03-01

    This report aims at consolidating existing data useful in defining the hydrologic characteristics of the Pasco Basin within south-central Washington. It also aims at compiling the properties required to evaluate contaminant transport potential within individual subsurface strata in this basin. The Pasco Basin itself is a tract of semi-arid land covering about 2,000 square miles in south-central Washington. The regional geology of this basin is dominated by tholeiitic flood basalts of the Columbia Plateau. The surface hydrology of the basin is dominated by the Yakima, Snake, and Columbia rivers. Short-lived ephemeral streams may flow for a short period of time after a heavy rainfall or snowmelt. The subsurface hydrology of the Pasco Basin is characterized by an unconfined aquifer carrying the bulk of the water discharged within the basin. This aquifer overlies a series of confined aquifers carrying progressively smaller amounts of groundwater as a function of depth. The hydraulic properties of the various aquifers and non-water-bearing strata are characterized and reported. A summary of the basic properties is tabulated. The hydrochemical data obtained are summarized. The contaminant transport properties of the rocks in the Pasco Basin are analyzed with emphasis on the dispersion and sorption coefficients and the characteristics of the potential reactions between emplaced waste and the surrounding medium. Some basic modeling considerations of the hydrogeologic systems in the basin with a brief discussion of model input requirements and their relationship to available data are presented

  3. Outlier identification and visualization for Pb concentrations in urban soils and its implications for identification of potential contaminated land

    International Nuclear Information System (INIS)

    Zhang Chaosheng; Tang Ya; Luo Lin; Xu Weilin

    2009-01-01

    Outliers in urban soil geochemical databases may imply potential contaminated land. Different methodologies which can be easily implemented for the identification of global and spatial outliers were applied for Pb concentrations in urban soils of Galway City in Ireland. Due to its strongly skewed probability feature, a Box-Cox transformation was performed prior to further analyses. The graphic methods of histogram and box-and-whisker plot were effective in identification of global outliers at the original scale of the dataset. Spatial outliers could be identified by a local indicator of spatial association of local Moran's I, cross-validation of kriging, and a geographically weighted regression. The spatial locations of outliers were visualised using a geographical information system. Different methods showed generally consistent results, but differences existed. It is suggested that outliers identified by statistical methods should be confirmed and justified using scientific knowledge before they are properly dealt with. - Outliers in urban geochemical databases can be detected to provide guidance for identification of potential contaminated land.

  4. Potential accumulation of contaminated sediments in a reservoir of a high-Andean watershed: Morphodynamic connections with geochemical processes

    Science.gov (United States)

    Contreras, María. Teresa; Müllendorff, Daniel; Pastén, Pablo; Pizarro, Gonzalo E.; Paola, Chris; Escauriaza, Cristián.

    2015-05-01

    Rapid changes due to anthropic interventions in high-altitude environments, such as the Altiplano region in South America, require new approaches to understand the connections between physical and geochemical processes. Alterations of the water quality linked to the river morphology can affect the ecosystems and human development in the long term. The future construction of a reservoir in the Lluta River, located in northern Chile, will change the spatial distribution of arsenic-rich sediments, which can have significant effects on the lower parts of the watershed. In this investigation, we develop a coupled numerical model to predict and evaluate the interactions between morphodynamic changes in the Lluta reservoir, and conditions that can potentially desorb arsenic from the sediments. Assuming that contaminants are mobilized under anaerobic conditions, we calculate the oxygen concentration within the sediments to study the interactions of the delta progradation with the potential arsenic release. This work provides a framework for future studies aimed to analyze the complex connections between morphodynamics and water quality, when contaminant-rich sediments accumulate in a reservoir. The tool can also help to design effective risk management and remediation strategies in these extreme environments. This article was corrected on 15 JUNE 2015. See the end of the full text for details.

  5. Outlier identification and visualization for Pb concentrations in urban soils and its implications for identification of potential contaminated land

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Chaosheng, E-mail: chaosheng.zhang@nuigalway.i [School of Geography and Archaeology, National University of Ireland, Galway (Ireland); Tang Ya [Department of Environmental Sciences, Sichuan University, Chengdu, Sichuan 610065 (China); Luo Lin; Xu Weilin [State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, Sichuan 610065 (China)

    2009-11-15

    Outliers in urban soil geochemical databases may imply potential contaminated land. Different methodologies which can be easily implemented for the identification of global and spatial outliers were applied for Pb concentrations in urban soils of Galway City in Ireland. Due to its strongly skewed probability feature, a Box-Cox transformation was performed prior to further analyses. The graphic methods of histogram and box-and-whisker plot were effective in identification of global outliers at the original scale of the dataset. Spatial outliers could be identified by a local indicator of spatial association of local Moran's I, cross-validation of kriging, and a geographically weighted regression. The spatial locations of outliers were visualised using a geographical information system. Different methods showed generally consistent results, but differences existed. It is suggested that outliers identified by statistical methods should be confirmed and justified using scientific knowledge before they are properly dealt with. - Outliers in urban geochemical databases can be detected to provide guidance for identification of potential contaminated land.

  6. Contaminant Gradients in Trees: Directional Tree Coring Reveals Boundaries of Soil and Soil-Gas Contamination with Potential Applications in Vapor Intrusion Assessment.

    Science.gov (United States)

    Wilson, Jordan L; Samaranayake, V A; Limmer, Matthew A; Schumacher, John G; Burken, Joel G

    2017-12-19

    Contaminated sites pose ecological and human-health risks through exposure to contaminated soil and groundwater. Whereas we can readily locate, monitor, and track contaminants in groundwater, it is harder to perform these tasks in the vadose zone. In this study, tree-core samples were collected at a Superfund site to determine if the sample-collection location around a particular tree could reveal the subsurface location, or direction, of soil and soil-gas contaminant plumes. Contaminant-centroid vectors were calculated from tree-core data to reveal contaminant distributions in directional tree samples at a higher resolution, and vectors were correlated with soil-gas characterization collected using conventional methods. Results clearly demonstrated that directional tree coring around tree trunks can indicate gradients in soil and soil-gas contaminant plumes, and the strength of the correlations were directly proportionate to the magnitude of tree-core concentration gradients (spearman's coefficient of -0.61 and -0.55 in soil and tree-core gradients, respectively). Linear regression indicates agreement between the concentration-centroid vectors is significantly affected by in planta and soil concentration gradients and when concentration centroids in soil are closer to trees. Given the existing link between soil-gas and vapor intrusion, this study also indicates that directional tree coring might be applicable in vapor intrusion assessment.

  7. Removal of NAPLs from the unsaturated zone using steam: prevention of downward migration by injecting mixtures of steam and air

    DEFF Research Database (Denmark)

    Schmidt, R.; Gudbjerg, Jacob; Sonnenborg, Torben Obel

    2002-01-01

    injection technology is presented, where a mixture of steam and air was injected. In twodimensional experiments with unsaturated porous medium contaminated with nonaqueous phase liquids, it was demonstrated how injection of pure steam lead to severe downward migration. Similar experiments, where steam......Steam injection for remediation of porous media contaminated by nonaqueous phase liquids has been shown to be a potentially efficient technology. There is, however, concern that the technique may lead to downward migration of separate phase contaminant. In this work, a modification of the steam...... and air were injected simultaneously, resulted in practically no downward migration and still rapid cleanup was achieved. The processes responsible for the prevention of downward migration when injecting steam–air mixtures were analyzed using a nonisothermal multiphase flow and transport model. Hereby...

  8. Environmental dioxin contamination in Chapaevsk, Russia: an evaluation of potential human health risks

    Energy Technology Data Exchange (ETDEWEB)

    Revich, B. [Center for Demography and Human Ecology of Inst. for Forecasting, Russian Academy of Sciences, Moscow (Russian Federation); Sergeyev, O. [Chapaevsk Medical Association, Chapaevsk (Russian Federation); Zeilert, V. [Central Medical Hospital, Chapaevsk (Russian Federation); Hauser, R. [Dept. of Environmental Health, Harvard School of Public Health, Boston (United States)

    2004-09-15

    The town of Chapaevsk (population 80 thousand) is located in Middle Volga region. During 1967- 1987 a chemical plant there produced hexachlorcyclohexan (lindan) and its derivatives. Later it produced crop protection chemicals (liquid chlorine, acids, methyl chloroform, vinyl chloride, and some other chemicals). Previously it was considered that hexachlorane production was responsible for dioxin contamination in the city's environment. Tests seemed to confirm it. But after the production was stopped in 1987, a continued output of dioxin was still observed. At present the plant stands practically idle; the main contamination source is represented by the old technological equipment, the plant's territory and industrial wastes. In 1994 an average concentration of dioxins in the air was 0.116 pg/m{sup 3}. The calculations were made when the plant worked at 20% capacity, so one can extrapolate that dioxin air emissions had been higher previously. Moving away from the plant one can see the decrease in dioxin levels down to 36.8 ng/kg in downtown (2.7 km from the plant); down to 3.9 ng/kg in the southern part of the city; down to 0.9 ng/kg at 10 - 15 km from the plant. Private house owners (18,000 in Chapaevsk) grow essentially all their vegetables and fruits for their own use, thus receiving an additional dioxin load. The results received in Chapaevsk boys study show a high proportion of the boys consumed locally grown or raised foods during their lifetime: over 70% consumed locally produced dairy products, over 50% consumed locally raised chickens or eggs, and over 80% consumed locally caught fish during their lifetime. In 1994 we began studies of dioxins impact on human health with the following aims: (1) to estimate dioxin levels in human blood and milk; (2) to estimate incidence and mortality rates, and specifically describe reproductive health in the population according to official statistical data; (3) to estimate dioxin exposure as a risk factor for

  9. Mining the Museum in an Age of Migration

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2014-01-01

    with the aim of ‘mining’ and thereby undermining colonial perceptions of the world. If so, it is of particular relevance to museums: decolonial institutional interventions as a means to turn museums into sites of contamination capable of including formerly repressed histories and migrating memories. Second......, to which degree Mignolo’s equation of an artist’s intervention with the politics of decoloniality really captures the transformative potential of artists’ interventions in museums in an age of migration, when the much desired diversity of audiences should also be mirrored in the chosen exhibits and modes...

  10. Traditional herbal medicines: potential degradation of sterols and sterolins by microbial contaminants

    Directory of Open Access Journals (Sweden)

    S. Govender

    2010-01-01

    Full Text Available Medicinal plants with a high content of sterols and sterolins, such as Bulbine natalensis (rooiwortel and Hypoxis hemerocallidea (African potato, are commonly and inappropriately used in South Africa for the treatment of HIV/AIDS due to the inaccessibility of antiretroviral drugs. This study investigated the presence of active compounds, such as sterols and sterolins, in the herbal medicines. The research was carried out in the Nelson Mandela Metropole area. The effect of microbial contaminants isolated from the medicines on sterols and sterolins of rooiwortel extracts was assessed. Sterols and sterolins were detected in rooiwortel, raw African potatoes and one ready-made mixture. Co-incubation of rooiwortel with bacteria (Bacillus spp. and Pseudomonas putida and fungi (Aspergillus spp., Penicillium spp. and Mucor spp. that were isolated from these samples increased the rate of degradation of sterols and sterolins over time, with slower degradation at 4°C than at 28°C.

  11. Microbial diversity and anaerobic hydrocarbon degradation potential in an oil-contaminated mangrove sediment.

    Science.gov (United States)

    Andrade, Luiza L; Leite, Deborah C A; Ferreira, Edir M; Ferreira, Lívia Q; Paula, Geraldo R; Maguire, Michael J; Hubert, Casey R J; Peixoto, Raquel S; Domingues, Regina M C P; Rosado, Alexandre S

    2012-08-30

    Mangrove forests are coastal wetlands that provide vital ecosystem services and serve as barriers against natural disasters like tsunamis, hurricanes and tropical storms. Mangroves harbour a large diversity of organisms, including microorganisms with important roles in nutrient cycling and availability. Due to tidal influence, mangroves are sites where crude oil from spills farther away can accumulate. The relationship between mangrove bacterial diversity and oil degradation in mangrove sediments remains poorly understood. Mangrove sediment was sampled from 0-5, 15-20 and 35-40 cm depth intervals from the Suruí River mangrove (Rio de Janeiro, Brazil), which has a history of oil contamination. DGGE fingerprinting for bamA, dsr and 16S rRNA encoding fragment genes, and qPCR analysis using dsr and 16S rRNA gene fragment revealed differences with sediment depth. Analysis of bacterial 16S rRNA gene diversity revealed changes with depth. DGGE for bamA and dsr genes shows that the anaerobic hydrocarbon-degrading community profile also changed between 5 and 15 cm depth, and is similar in the two deeper sediments, indicating that below 15 cm the anaerobic hydrocarbon-degrading community appears to be well established and homogeneous in this mangrove sediment. qPCR analysis revealed differences with sediment depth, with general bacterial abundance in the top layer (0-5 cm) being greater than in both deeper sediment layers (15-20 and 35-40 cm), which were similar to each other.

  12. Mercury contamination, a potential threat to the globally endangered aquatic warbler Acrocephalus paludicola.

    Science.gov (United States)

    Pacyna, Aneta Dorota; Martínez, Carlos Zumalacárregui; Miguélez, David; Jiguet, Frédéric; Polkowska, Żaneta; Wojczulanis-Jakubas, Katarzyna

    2017-12-01

    Mercury (Hg) contamination is considered a global concern for humans and wildlife, and although the number of studies dealing with that issue continues to increase, some taxonomic groups such as small passerine birds are largely understudied. In this paper, concentration of mercury in the aquatic warbler (Acrocephalus paludicola) feathers, a globally threatened passerine species, was examined. The concentration differences between two ages and sexes were investigated. The comparison of feathers taken on autumn migrants of two age categories act as a comparison of the species' exposure within the two different areas (European breeding or African wintering grounds). The average Hg concentration for all sampled individuals [2.32 μg/g dw (range 0.38-12.76)] is relatively high, compared with values found in other passerine species. An age difference was found, with first-year individuals displaying higher mercury concentrations than adults. This indicates that birds are exposed to mercury pollution during the breeding season, i.e., in the continental floodplains of eastern Europe. The average Hg concentration in feathers grown on the breeding grounds was 3.88 ± 2.59 μg/g dw, closer to the critical value of 5 μg/g dw, which is considered to impair the health of individuals. The findings suggest that mercury pollution may constitute a threat so far neglected for the endangered aquatic warbler.

  13. Activated carbon prepared from coffee pulp: potential adsorbent of organic contaminants in aqueous solution.

    Science.gov (United States)

    Gonçalves, Maraisa; Guerreiro, Mário César; Ramos, Paulize Honorato; de Oliveira, Luiz Carlos Alves; Sapag, Karim

    2013-01-01

    The processing of coffee beans generates large amounts of solid and liquid residues. The solid residues (pulp, husk and parchment) represent a serious environmental problem and do not have an adequate disposal mechanism. In this work, activated carbons (ACs) for adsorption of organic compounds were prepared from coffee pulp by controlled temperature at different pulp/Na2HPO4 ratios (4:1, 2:1, 5:4 and 1:1). The N2 adsorption/desorption isotherms showed ACs with high quantities of mesopores and micropores and specific surface areas of 140, 150, 450 and 440 m(2)g(-1) for AC 4:1, AC 2:1, AC 5:4 and AC 1:1, respectively. The prepared material AC 5:4 showed a higher removal capacity of the organic contaminants methylene blue (MB), direct red (DR) and phenol than did a Merck AC. The maximum capacities for this AC are approximately 150, 120 and 120 mg g(-1) for MB, DR and phenol, respectively. Thus, a good adsorbent was obtained from coffee pulp, an abundant Brazilian residue.

  14. Doses from potential inhalation by people living near plutonium contaminated areas

    International Nuclear Information System (INIS)

    Iranzo Gonzales, E.; Salvador Ruiz, S.

    1983-09-01

    An aviation accident above the town of Palomares, Spain resulted in four thermonuclear bombs carried by one of the planes falling. The nuclear fuel in two of them ignited and formed an aerosol which contaminated a 226-hectare area of underbrush, farmland and an urban center. The magnitude of risk to people living in the area who may have inhaled the plutonium aerosol or dusts during the fifteen-year period since the time the accident is addressed in this report. In addition the internal radiation doses that people may have received during this period and during a fifty-year period commencing with the accident is estimated. In brief summary, the lungs received the greatest dose equivalent (1966 to 1980). Over the fifty year period (to 2015) the bones are projected to receive the greatest dose. For the remaining organs - liver-intestines-kidneys, - the relationships or between the doses that will be accumulated up to the year 2015 and the corresponding annual dose equivalent limits are less than those for the bones and lungs

  15. Oil and gas development and the potential for contamination of moose (Alces alces) in northeast BC

    International Nuclear Information System (INIS)

    Maundrell, C.; Roe, N.

    2007-01-01

    Traditional sources of food for meat, berries, and fish are relied upon by First Nations of northern Canada. Hunting and trapping in traditional areas are the primary sources of protein consumption by First Nations. In the Northwest Territories and northeast British Columbia (BC), moose meat (Alces alces) is one of the most sought after meats. Therefore, an important consideration needing documentation was to determine if animals in areas of high oil and gas development were unhealthy compared to animals living in areas of low or no oil and gas activity. This paper presented the results of a study that documented the presence of contaminants in harvested moose. The main purpose of the study was to analyze moose tissue samples for extractable petroleum hydrocarbons, heavy metals and polycyclic hydrocarbons. The paper also discussed the methodology used in harvesting the moose which involved shooting them with a high powered rifle to collect tissue samples. Levels of concentration in tissues between two areas with noticeably different levels of oil and gas activity were then compared. Significantly higher levels of heavy metal concentrations were found in tissues sampled from the treatment area. It was therefore concluded that oil and gas activity may have negative impacts on the health of moose in northeast BC. 8 refs., 2 tabs

  16. Genesis Solar Wind Science Canister Components Curated as Potential Solar Wind Collectors and Reference Contamination Sources

    Science.gov (United States)

    Allton, J. H.; Gonzalez, C. P.; Allums, K. K.

    2016-01-01

    The Genesis mission collected solar wind for 27 months at Earth-Sun L1 on both passive and active collectors carried inside of a Science Canister, which was cleaned and assembled in an ISO Class 4 cleanroom prior to launch. The primary passive collectors, 271 individual hexagons and 30 half-hexagons of semiconductor materials, are described in. Since the hard landing reduced the 301 passive collectors to many thousand smaller fragments, characterization and posting in the online catalog remains a work in progress, with about 19% of the total area characterized to date. Other passive collectors, surfaces of opportunity, have been added to the online catalog. For species needing to be concentrated for precise measurement (e.g. oxygen and nitrogen isotopes) an energy-independent parabolic ion mirror focused ions onto a 6.2 cm diameter target. The target materials, as recovered after landing, are described in. The online catalog of these solar wind collectors, a work in progress, can be found at: http://curator.jsc.nasa.gov/gencatalog/index.cfm This paper describes the next step, the cataloging of pieces of the Science Canister, which were surfaces exposed to the solar wind or component materials adjacent to solar wind collectors which may have contributed contamination.

  17. Potential of MuS1 Transgenic Tobacco for Phytoremediation of the Urban Soils Contaminated with Cadmium

    Science.gov (United States)

    Kim, K. H.; Kim, Y. N.; Kim, S. H.

    2010-05-01

    Urban soils are prone to contamination by trace elements such as Cd, Cu, Pb and Zn. Phytoremediation is one of the attractive remediation methods for soils contaminated with trace elements due to its non-destructive and environmentally-friendly characteristic. Scientists have tried to find hyper-accumulator plants in nature or to develop transgenic plant through genetic engineering. This study was carried out to identify a potential of MuS1 transgenic tobacco for phytoremediation of the urban soils contaminated with Cd. MuS1 is known as a multiple stress related gene with several lines. The previous study using RT-PCR showed that the expression of MuS1 gene in tobacco plant induced tolerance to Cd stress. For this study, MuS1 transgenic tobacco and wild-type tobacco (control) were cultivated in a hydroponic system treated with Cd (0, 50, 100 and 200μM Cd) for 3 weeks. At harvest, both tobacco and nutrient solution were collected and were analyzed for Cd. Effect of Cd treatment on morphological change of the tobacco leaves was also observed by variable-pressure scanning electron microscopy (VP-SEM). The tolerance of MuS1 transgenic tobacco to Cd stress was better than that of wild-type tobacco at all Cd levels. Especially, wild-type tobacco showed chlorosis and withering with 200μM Cd treatment, whereas MuS1 transgenic tobacco gradually recovered from Cd damage. Wild-type tobacco accumulated more Cd (4.65mg per plant) than MuS1 transgenic tobacco (2.37mg per plant) with 200μM Cd treatment. Cd translocation rate from root to leaves was 81.8 % for wild-type tobacco compared to 37.1 % for MuS1 transgenic tobacco. Result of VP-SEM showed that the number of trichome in the leaves for wild-type tobacco increased in comparison with that for untreated samples after 3 weeks, while that for MuS1 transgenic tobacco was not changed by Cd treatment. Results showed that the mechanism of the recovery of the MuS1 tobacco plant was not by high level of Cd uptake and accumulation

  18. Groundwater contaminant plume ranking

    International Nuclear Information System (INIS)

    1988-08-01

    Containment plumes at Uranium Mill Tailings Remedial Action (UMTRA) Project sites were ranked to assist in Subpart B