Science.gov

Sample records for environmental chemical contaminants

  1. Agricultural chemical application practices to reduce environmental contamination.

    PubMed

    Bode, L E

    1990-01-01

    Current practices of applying agricultural chemicals play a major role in the environmental health concerns of agriculture. Those who mix, load, and handle the concentrated formulations run the greatest risk of exposure but field hands and others can encounter significant levels of pesticides. Drift can be a major source of contamination to residents, wildlife, and water sources. Improved methods of application and ways of reducing the total amount of pesticide applied can help reduce environmental contamination. Chemigation, direct injection, closed system handling, and fertilizer impregnation are examples of technology that affect the efficiency of applying agricultural chemicals. An area of beneficial research is related to leak and spill technology. Current surveys indicate that point sources such as spills, mixing and loading areas, back-siphoning, and direct routes for surface water movement into the ground are often a major cause of pesticides reaching groundwater. The commercial dealer/applicator provides storage, handling, mixing, and loading for large amounts of chemicals and has received limited guidance regarding the products. Education remains an important element of any rural environmental health strategy. With appropriate information about pesticide risks and groundwater, people will be better equipped to address environmental concerns. By design, agricultural chemicals are biologically active and, in most cases, toxic. Thus, they pose potential risks to humans, wildlife, water, and the environment in general. The magnitude of the risks depends to some degree on the methods and techniques used to apply the chemicals. Pesticides are applied by persons possessing a variety of skills, using equipment ranging from hand-operated systems to aircraft. PMID:2248252

  2. Environmental contaminants

    PubMed Central

    2011-01-01

    Contaminants such as cadmium, bisphenol A and lead pollute our environment and affect male reproductive function. There is evidence that toxicant exposure adversely affects fertility. Cadmium and bisphenol A exert their effects in the testis by perturbing blood-testis barrier function, which in turn affects germ cell adhesion in the seminiferous epithelium because of a disruption of the functional axis between these sites. In essence, cadmium mediates its adverse effects at the blood-testis barrier by disrupting cell adhesion protein complexes, illustrating that toxicants can dismantle cell junctions in the testis. Herein, we will discuss how environmental toxicants may affect reproductive function. We will also examine how these adverse effects on fertility may be mediated in part by adipose tissue and bone. Lastly, we will briefly discuss how toxicant-induced damage may be effectively managed so that fertility can be maintained. It is hoped that this information will offer a new paradigm for future studies. PMID:22332111

  3. Endocrine-Disrupting Chemicals and Oil and Natural Gas Operations: Potential Environmental Contamination and Recommendations to Assess Complex Environmental Mixtures

    PubMed Central

    Kassotis, Christopher D.; Tillitt, Donald E.; Lin, Chung-Ho; McElroy, Jane A.; Nagel, Susan C.

    2015-01-01

    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. 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. Objectives 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. Methods 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. 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 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. Citation Kassotis CD, Tillitt DE, Lin CH, McElroy JA, Nagel SC. 2016. Endocrine-disrupting chemicals and oil and natural gas operations: potential environmental contamination and recommendations to assess complex environmental mixtures. Environ Health Perspect 124:256–264; http://dx.doi.org/10.1289/ehp.1409535 PMID:26311476

  4. Biological and chemical tests of contaminated soils to determine bioavailability and environmentally acceptable endpoints (EAE)

    SciTech Connect

    Montgomery, C.R.; Menzie, C.A.; Pauwells, S.J.

    1995-12-31

    The understanding of the concept of bioavailability of soil contaminants to receptors and its use in supporting the development of EAE is growing but still incomplete. Nonetheless, there is increased awareness of the importance of such data to determine acceptable cleanup levels and achieve timely site closures. This presentation discusses a framework for biological and chemical testing of contaminated soils developed as part of a Gas Research Institute (GRI) project entitled ``Environmentally Acceptable Endpoints in Soil Using a Risk Based Approach to Contaminated Site Management Based on Bioavailability of Chemicals in Soil.`` The presentation reviews the GRI program, and summarizes the findings of the biological and chemical testing section published in the GRI report. The three primary components of the presentation are: (1) defining the concept of bioavailability within the existing risk assessment paradigm, (2) assessing the usefulness of the existing tests to measure bioavailability and test frameworks used to interpret these measurements, and (3) suggesting how a small selection of relevant tests could be incorporated into a flexible testing scheme for soils to address this issue.

  5. Endocrine-disrupting chemicals and oil and natural gas operations: Potential environmental contamination and recommendations to assess complex environmental mixtures

    USGS Publications Warehouse

    Kassotis, Christopher D.; Tillitt, Donald E.; Lin, Chung-Ho; McElroy, Jane A.; Nagel, Susan C.

    2015-01-01

    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. Contaminated sediments: Lectures on environmental aspects of particle-associated chemicals in aquatic systems

    SciTech Connect

    Forstner, U.

    1989-01-01

    Sediments are increasingly recognized as both a carrier and a possible source of contaminants in aquatic systems. Since the early part of the century, limnological research on eutrophication problems and acidification indicated that particle-interactions can affect aquatic ecosystems. In contrast to the eutrophication and acidification problems, research on toxic chemicals has included sediment aspects from its beginning. In the lecture notes, following the description of priority pollutants related to sedimentary phases, four aspects were covered, which in an overlapping succession also reflect the development of knowledge in particle-associated pollutants during the past 25 years: the identification, surveillance, monitoring and control of sources and distribution of pollutants; the evaluation of solid/solution relations of contaminants in surface waters; the study of in-situ processes and mechanisms in pollutant transfer in various compartments of the aquatic ecosystems and, the assessment of the environmental impact of particle-bound contaminants. The last chapter focuses on dredged materials, including their disposal and the treatment of strongly contaminated sediments. Cases studies include the Niagara River/Lake Ontario pollution; solid speciation of metals in river sediments; the Rhine River; Puget Sound; Rotterdam Harbor; and the mobilization of cadmium from tidal river sediments.

  7. Estrogen-like activity of seafood related to environmental chemical contaminants

    PubMed Central

    Garritano, Sonia; Pinto, Barbara; Calderisi, Marco; Cirillo, Teresa; Amodio-Cocchieri, Renata; Reali, Daniela

    2006-01-01

    Background A wide variety of environmental pollutants occur in surface waters, including estuarine and marine waters. Many of these contaminants are recognised as endocrine disrupting chemicals (EDCs) which can adversely affect the male and female reproductive system by binding the estrogen receptor and exhibiting hormone-like activities. In this study the estrogenic activity of extracts of edible marine organisms for human consumption from the Mediterranean Sea was assayed. Methods Marine organisms were collected in two different areas of the Mediterranean Sea. The estrogenic activity of tissues was assessed using an in vitro yeast reporter gene assay (S. cerevisiae RMY 326 ER-ERE). Concentrations of polychlorinated biphenyls (PCBs) (congeners 28, 52, 101, 118, 138, 153, 180) in fish tissue was also evaluated. Results Thirty-eight percent of extracts showed a hormone-like activity higher than 10% of the activity elicited by 10 nM 17b-estradiol (E2) used as control. Total PCB concentrations ranged from 0.002 up to 1.785 ng/g wet weight. Chemical analyses detected different levels of contamination among the species collected in the two areas, with the ones collected in the Adriatic Sea showing concentrations significantly higher than those collected in the Tyrrhenian Sea (p < 0.01). Conclusion The more frequent combination of chemicals in the samples that showed higher estrogenic activity was PCB 28, PCB 101, PCB 153, PCB 180. The content of PCBs and estrogenic activity did not reveal any significant correlation. PMID:16573822

  8. [Chemical food contaminants].

    PubMed

    Schrenk, D

    2004-09-01

    Chemical food contaminants are substances which are neither present naturally in the usual raw material used for food production nor are added during the regular production process. Examples are environmental pollutants or contaminants derived from agricultural production of crops or livestock or from inadequate manufacturing of the food product itself. More difficult is the classification of those compounds formed during regular manufacturing such as products of thermal processes including flavoring substances. In these cases, it is common practice to call those compounds contaminants which are known for their adverse effects such as acrylamide, whereas constituents which add to the food-specific flavor such as Maillard products formed during roasting, baking etc. are not termed contaminants. From a toxicological viewpoint this distinction is not always clear-cut. Important groups of chemical contaminants are metals such as mercury or lead, persistent organic pollutants such as polychlorinated biphenyls and related pollutants, which are regularly found in certain types of food originating from background levels of these compounds in our environment. Furthermore, natural toxins form microorganisms or plants, and compounds formed during thermal treatment of food are of major interest. In general, a scientific risk assessment has to be carried out for any known contaminant. This comprises an exposure analysis and a toxicological and epidemiological assessment. On these grounds, regulatory and/or technological measures can often improve the situation. Major conditions for a scientific risk assessment and a successful implementation of regulations are highly developed food quality control, food toxicology and nutritional epidemiology. PMID:15378171

  9. Epidemiologic evidence of relationships between reproductive and child health outcomes and environmental chemical contaminants.

    PubMed

    Wigle, Donald T; Arbuckle, Tye E; Turner, Michelle C; Brub, Annie; Yang, Qiuying; Liu, Shiliang; Krewski, Daniel

    2008-05-01

    This review summarizes the level of epidemiologic evidence for relationships between prenatal and/or early life exposure to environmental chemical contaminants and fetal, child, and adult health. Discussion focuses on fetal loss, intrauterine growth restriction, preterm birth, birth defects, respiratory and other childhood diseases, neuropsychological deficits, premature or delayed sexual maturation, and certain adult cancers linked to fetal or childhood exposures. Environmental exposures considered here include chemical toxicants in air, water, soil/house dust and foods (including human breast milk), and consumer products. Reports reviewed here included original epidemiologic studies (with at least basic descriptions of methods and results), literature reviews, expert group reports, meta-analyses, and pooled analyses. Levels of evidence for causal relationships were categorized as sufficient, limited, or inadequate according to predefined criteria. There was sufficient epidemiological evidence for causal relationships between several adverse pregnancy or child health outcomes and prenatal or childhood exposure to environmental chemical contaminants. These included prenatal high-level methylmercury (CH(3)Hg) exposure (delayed developmental milestones and cognitive, motor, auditory, and visual deficits), high-level prenatal exposure to polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs), and related toxicants (neonatal tooth abnormalities, cognitive and motor deficits), maternal active smoking (delayed conception, preterm birth, fetal growth deficit [FGD] and sudden infant death syndrome [SIDS]) and prenatal environmental tobacco smoke (ETS) exposure (preterm birth), low-level childhood lead exposure (cognitive deficits and renal tubular damage), high-level childhood CH(3)Hg exposure (visual deficits), high-level childhood exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (chloracne), childhood ETS exposure (SIDS, new-onset asthma, increased asthma severity, lung and middle ear infections, and adult breast and lung cancer), childhood exposure to biomass smoke (lung infections), and childhood exposure to outdoor air pollutants (increased asthma severity). Evidence for some proven relationships came from investigation of relatively small numbers of children with high-dose prenatal or early childhood exposures, e.g., CH(3)Hg poisoning episodes in Japan and Iraq. In contrast, consensus on a causal relationship between incident asthma and ETS exposure came only recently after many studies and prolonged debate. There were many relationships supported by limited epidemiologic evidence, ranging from several studies with fairly consistent findings and evidence of dose-response relationships to those where 20 or more studies provided inconsistent or otherwise less than convincing evidence of an association. The latter included childhood cancer and parental or childhood exposures to pesticides. In most cases, relationships supported by inadequate epidemiologic evidence reflect scarcity of evidence as opposed to strong evidence of no effect. This summary points to three main needs: (1) Where relationships between child health and environmental exposures are supported by sufficient evidence of causal relationships, there is a need for (a) policies and programs to minimize population exposures and (b) population-based biomonitoring to track exposure levels, i.e., through ongoing or periodic surveys with measurements of contaminant levels in blood, urine and other samples. (2) For relationships supported by limited evidence, there is a need for targeted research and policy options ranging from ongoing evaluation of evidence to proactive actions. (3) There is a great need for population-based, multidisciplinary and collaborative research on the many relationships supported by inadequate evidence, as these represent major knowledge gaps. Expert groups faced with evaluating epidemiologic evidence of potential causal relationships repeatedly encounter problems in summarizing the available data. A major driver for un

  10. Biomarkers of environmental contamination

    SciTech Connect

    McCarthy, J.F.; Shugart, L.R.

    1990-01-01

    Biological markers are measurements at the molecular, biochemical, or cellular level in either wild populations from contaminated habitats or in organisms experimentally exposed to pollutants that indicate that the organism has been exposed to toxic chemicals, and the magnitude of the organisms response to the contaminant. Biological markers measured in wild animals can directly contribute to detecting, quantifying, and understanding the significance of exposure to chemicals in the environment. These measurements in environmental species may also help assess the potential for human exposure to environmental pollutants, and for predicting the human health risks. It is the objective of this volume to review the current state of science as it pertains to the scientific basis, current state of development, validation, and use of biological markers in environmental research. The emphasis is on identifying and evaluating exposure of environmental species and effects on the health of environmental species and the integrity of their ecosystem. The various chapters describe different types of biomarkers that offer promise for environmental monitoring. The biomarkers are arranged in categories defined by the nature of the toxic endpoint being probed: anatomical and cytological endpoints; detoxification, adaptive and immunological responses; genotoxic responses; metal metabolism; and application of biomarkers in field evaluation.

  11. Utilizing high-throughput bioassays associated with US EPA ToxCast Program to assess biological activity of environmental contaminants: A case study of chemical mixtures

    EPA Science Inventory

    Effects-based monitoring and surveillance is increasingly being utilized in conjunction with chemical monitoring to determine potential biological activity associated with environmental contaminants. Supervised approaches targeting specific chemical activity or molecular pathways...

  12. International Mussel Watch: A global assessment of environmental levels of chemical contaminants

    SciTech Connect

    Not Available

    1992-01-01

    The primary goal of the International Mussel Watch is to ascertain and assess the levels of chlorinated hydrocarbon pesticide (CHP) and polychlorinated biphenyls (PCB) in bivalves collected from coastal marine waters throughout the world. Increased use of these persistent toxic biocides may result in contamination of living coastal resources from whole ecosystems to specific food resources with consequent implication for human health and the integrity of marine communities. Another goal for the International Mussel Watch Project will be to help develop a sustainable activity for observation and monitoring chemical contamination in especially susceptible regions of the world's oceans.

  13. INTERACTIVE EFFECTS OF ENDOCRINE DISRUPTING CHEMICALS (EDCS): THYROID HORMONE HOMEOSTASIS AS A TARGET FOR ENVIRONMENTAL CONTAMINANTS

    EPA Science Inventory

    A wide range of chemicals with diverse structures act as thyrotoxicants. Broadly defined, thyrotoxicants are chemicals that alter the structure or function of the thyroid gland, alter regulatory enzymes associated with thyroid hormones (THs), or change circulating or tissue conce...

  14. Biomonitoring of Environmental Status and Trends (BEST) Program: selected methods for monitoring chemical contaminants and their effects in aquatic ecosystems

    USGS Publications Warehouse

    Schmitt, Christopher J.; Dethloff, Gail M.

    2000-01-01

    This document describes the suite of biological methods of the U.S. Geological Survey- Biomonitoring of Environmental Status and Trends program for monitoring chemical contaminants and their effects on fish. The methods, which were selected by panels of experts, are being field-tested in rivers of the Mississippi River, Columbia River, and Rio Grande basins. General health biomarkers include a health assessment index based on gross observation; histopathological examination of selected organs and tissues; condition factor; and the heptosomatic and splenosomatic indices. Immune system indicators are plasma lysozyme activity and measures of splenic macrophage aggregates. Reproductive biomarkers include plasma concentrations of sex steroid hormones (17b-estradiol and 11-ketotestosterone) and vitellogenin, gonadal histopathology (including reproductive stage and, in females, gonadal atresia), and the gonadosomatic index. Indicators of exposure to polycyclic aromatic and polyhalogenated hydrocarbons are the H4IIE rat hepatoma cell bioassay (performed on solvent extracts of composite fish samples) and hepatic ethoxyresorufin-O-deethylase activity. Stable nitrogen isotope ratios are used to assess the trophic position of the fish and their exposure to sewage and other animal wastes. For each indicator we describe endpoint(s) and methods, and discuss the indicator?s value and limitations for contaminant monitoring and assessment.

  15. Chemical contaminants in human milk: an overview.

    PubMed Central

    Sonawane, B R

    1995-01-01

    This review contains a succinct overview of the nature and extent of the problem of contamination of human milk with environmental and occupational chemicals, excluding drugs. Factors influencing the levels of contaminants in breast milk are discussed. Also, data on major chemicals of concern with potential health risk(s) to the general population and risk-benefit considerations are dealt with briefly. Based on the available data on the subject, research needs have been identified and policy recommendations are suggested. PMID:8549474

  16. In vivo and in vitro absorption and binding to powdered stratum corneum as methods to evaluate skin absorption of environmental chemical contaminants from ground and surface water

    SciTech Connect

    Wester, R.C.; Mobayen, M.; Maibach, H.I.

    1987-01-01

    The objectives of this study were to compare methods to determine the binding and absorption of water contaminants to skin, to examine linearity of response, and to determine whether skin was an environmental route for water contaminants to enter the body. The three chemical examined were (/sup 14/C)-p-nitroaniline (10.1 mCi/mM), (/sup 14/C)benzene (56 mCi/mM, and /sup 14/C-labeled 54% PCB (32 mCi/mM). The chemical were added to distilled water and the concentration in water was determined by liquid scintillation counting.

  17. Karst hydrology and chemical contamination

    SciTech Connect

    Field, M.S.

    1993-01-01

    Ground-water flow in karst aquifers is very different from flow in granular or fractured aquifers. Chemical contamination may be fed directly to a karst aquifer via overland flow to a sinkhole with little or no attenuation and may contaminate downgradient wells, springs, and sinkholes within a few hours or a few days. Contaminants may also become temporarily stored in the epikarstic zone for eventual release to the aquifer. Flood pulses may flush the contaminants to cause transiently higher levels of contamination in the aquifer and discharge points. The convergent nature of flow in karst aquifers may result in contaminants becoming concentrated in conduits. Once contaminants have reached the subsurface conduits, they are likely to be rapidly transported to spring outlets. Traditional aquifer remediation techniques for contaminated aquifers are less applicable to karst aquifers.

  18. [Chemical contaminants in food].

    PubMed

    Coduro, E

    1986-12-01

    Due to a direct material linking between environment and man via breath, food and potable water, toxic substances have always been in the food of man, only modern analytical methods have made it possible to safely register concentrations in the ppb-range and below. This is why we discover more and more potential hazardous substances in food, becoming conscious of the full extent of contamination more and more. Such concentrations make a toxicological evaluation very difficult, most of all when a long-term effect is concerned. There are different reasons for the occurrence of toxic substances in our food. Substances occurring naturally in food like trypsin inhibitors, solanine and cumarin. Substances that are added to food purposely. To these belong artificial dyes and sweetening agents, sulphur dioxide and pesticides resp. herbicides. Substances that are formed during the production, preparation or storage of food like polycyclic aromatic hydrocarbons, peroxides of unsaturated fatty acids, mycotoxins and nitrosamines. Substances that are taken in due to environmental influences, considering primarily the toxic heavy metals lead, cadmium and mercury as well as polychlorinated biphenyls (PCBs). Legislative authorities have taken numerous steps to protect the consumer against food that is detrimental to his health, based mainly on the so-called "principle of prohibition" that stands for the general prohibition of additives as long as they are not formally permitted. The fundamental prohibition of the "Lebensmittel- und Bedarfsgegenstndegesetz" (law for food and requirements) to produce or handle food in such a way that its consumption is qualified to harm the health of the consumer, has an extensive protective effect. This effect is supported by regulation for additives and special directives. An important group of possibly toxic substances in our food are pesticides and their residues. In 1985 1839 pesticides based on 302 active components were officially admitted in the Federal Republic of Germany, 40% of these as herbicides, 23% as insecticides. The investigations of the food control authorities are oriented on the regulation of maximum amounts for pesticides which includes maximum values for about 470 active substances. There is a report on special investigations of the "Landesuntersuchungsamt" (office for the investigation of food and requirements).(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3107271

  19. Chemical and biological methods for the analysis and remediation of environmental contaminants frequently identified at superfund sites

    SciTech Connect

    Melinda Christine Wiles

    2004-08-15

    Substantial environmental contamination has occurred from coal tar creosote and pentachlorophenol (C5P) in wood preserving solutions. The present studies focused on the characterization and remediation of these contaminants. The first objective was to delineate a sequence of biological changes caused by chlorinated phenol (CP) exposure. The second study was to develop multi-functional sorbents to remediate CPs and other components of wood preserving waste from groundwater. Following water remediation, the final aim of this work was to explore the safety of the parent clay minerals as potential enterosorbents for contaminants ingested in water and food. Based on evaluations of toxicity and neutron activation analysis of tissues, no significant differences were observed between animals receiving clay supplements and control animals, with the exception of slightly decreased brain Rb in animals ingesting clay. Overall, the results suggest that neither clay mineral, at relatively high dietary concentrations, influences mineral uptake or utilization in the pregnant rat. 420 refs., 28 figs, 15 tabs.

  20. 2008 Meeting in Germany: Emerging Environmental Contaminants and Current Issues

    EPA Science Inventory

    This presentation will discuss emerging environmental contaminants that are currently of concern to the U.S. EPA and to other agencies. Emerging contaminants include drinking water disinfection by-products (DBPs), perfluorinated chemicals, pharmaceuticals, flame retardants, benzo...

  1. Environmental contamination in Antarctic ecosystems.

    PubMed

    Bargagli, R

    2008-08-01

    Although the remote continent of Antarctica is perceived as the symbol of the last great wilderness, the human presence in the Southern Ocean and the continent began in the early 1900s for hunting, fishing and exploration, and many invasive plant and animal species have been deliberately introduced in several sub-Antarctic islands. Over the last 50 years, the development of research and tourism have locally affected terrestrial and marine coastal ecosystems through fuel combustion (for transportation and energy production), accidental oil spills, waste incineration and sewage. Although natural "barriers" such as oceanic and atmospheric circulation protect Antarctica from lower latitude water and air masses, available data on concentrations of metals, pesticides and other persistent pollutants in air, snow, mosses, lichens and marine organisms show that most persistent contaminants in the Antarctic environment are transported from other continents in the Southern Hemisphere. At present, levels of most contaminants in Antarctic organisms are lower than those in related species from other remote regions, except for the natural accumulation of Cd and Hg in several marine organisms and especially in albatrosses and petrels. The concentrations of organic pollutants in the eggs of an opportunistic top predator such as the south polar skua are close to those that may cause adverse health effects. Population growth and industrial development in several countries of the Southern Hemisphere are changing the global pattern of persistent anthropogenic contaminants and new classes of chemicals have already been detected in the Antarctic environment. Although the Protocol on Environmental Protection to the Antarctic Treaty provides strict guidelines for the protection of the Antarctic environment and establishes obligations for all human activity in the continent and the Southern Ocean, global warming, population growth and industrial development in countries of the Southern Hemisphere will likely increase the impact of anthropogenic contaminants on Antarctic ecosystems. PMID:18765160

  2. Minimally invasive transcriptome profiling in salmon: detection of biological response in rainbow trout caudal fin following exposure to environmental chemical contaminants.

    PubMed

    Veldhoen, Nik; Stevenson, Mitchel R; Skirrow, Rachel C; Rieberger, Kevin J; van Aggelen, Graham; Meays, Cynthia L; Helbing, Caren C

    2013-10-15

    An increasing number of anthropogenic chemicals have demonstrated potential for disruption of biological processes critical to normal growth and development of wildlife species. Both anadromous and freshwater salmon species are at risk of exposure to environmental chemical contaminants that may affect migratory behavior, environmental fitness, and reproductive success. A sensitive metric in determination of the presence and impact of such environmental chemical contaminants is through detection of changes in the status of gene transcript levels using a targeted quantitative real-time polymerase chain reaction assay. Ideally, the wildlife assessment strategy would incorporate conservation-centered non-lethal practices. Herein, we describe the development of such an assay for rainbow trout, Oncorhynchus mykiss, following an acute 96 h exposure to increasing concentrations of either 17?-ethinyl estradiol or cadmium. The estrogenic screen included measurement of mRNA encoding estrogen receptor ? and ? isoforms, vitellogenin, vitelline envelope protein ?, cytochrome p450 family 19 subfamily A, aryl hydrocarbon receptor, and the stress indicator, catalase. The metal exposure screen included evaluation of the latter two mRNA transcripts along with those encoding the metallothionein A and B isoforms. Exposure-dependent transcript abundance profiles were detected in both liver and caudal fin supporting the use of the caudal fin as a non-lethally obtained tissue source. The potential for both transcriptome profiling and genotypic sex determination from fin biopsy was extended, in principle, to field-captured Chinook salmon (Oncorhynchus tshawytscha). PMID:24055988

  3. ENVIRONMENTAL CHEMISTRY: EMERGING CONTAMINANTS AND CURRENT ISSUES

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise. This presentation will discuss chemical and microbial contaminants that the U.S. EPA and other agencies are currently concerned about. In this gr...

  4. Perchlorate as an environmental contaminant.

    PubMed

    Urbansky, Edward Todd

    2002-01-01

    Perchlorate anion (ClO4-) has been found in drinking water supplies throughout the southwestern United States. It is primarily associated with releases of ammonium perchlorate by defense contractors, military operations, and aerospace programs. Ammonium perchlorate is used as a solid oxidant in missile and rocket propulsion systems. Traces of perchlorate are found in Chile saltpeter, but the use of such fertilizer has not been associated with large scale contamination. Although it is a strong oxidant, perchlorate anion is very persistent in the environment due to the high activation energy associated with its reduction. At high enough concentrations, perchlorate can affect thyroid gland functions, where it is mistakenly taken up in place of iodide. A safe daily exposure has not yet been set, but is expected to be released in 2002. Perchlorate is measured in environmental samples primarily by ion chromatography. It can be removed by anion exchange or membrane filtration. It is destroyed by some biological and chemical processes. The environmental occurrence, toxicity, analytical chemistry, and remediative approaches are discussed. PMID:12094532

  5. Data-Mining and Informatics Approaches for Environmental Contaminants

    EPA Science Inventory

    New and emerging environmental contaminants are chemicals that have not been previously detected or that are being detected at levels significantly different from those expected in both biological and ecological arenas (that is, human, wildlife, and environment). Many chemicals c...

  6. Environmental Contaminants in Wildlife: Interpreting Tissue Concentrations

    USGS Publications Warehouse

    1996-01-01

    Covers the complex issue of how to evaluate contaminants in wildlife. This comprehensive resource deals with the question: 'How much of a chemical in the tissues of an animal is harmful?' Features: Authoritative and sound advice is provided on many environmental contaminants, including what the contaminants are and how to interpret the data on them. Each chapter includes a review of the literature on a specific chemical, followed by a clear technical summary that provides research guidance. Direction is given on how to interpret data that are sometimes conflicting or insufficient. Data are presented in easy to use tables. Primary attention is given to toxic concentrations of contaminants such as organochlorine pesticides, PCBs, dioxins, PAHs, metals, and fluorides.

  7. Chemical and Environmental Technology.

    ERIC Educational Resources Information Center

    Sheather, Harry

    The two-year curriculum in chemical technology presented in the document is designed to prepare high school graduates for technical positions in the chemical industry. Course outlines are given for general chemistry, chemical calculations, quantitative analysis, environmental chemistry, organic chemistry 1 and 2, instrumental analysis, and…

  8. NEGATIVE CHEMICAL IONIZATION STUDIES OF HUMAN AND FOOD CHAIN CONTAMINATION WITH XENOBIOTIC CHEMICALS

    EPA Science Inventory

    Negative chemical ionization mass spectrometry with a mixture of isobutane, methylene chloride, and oxygen as the reagent gas has been used to explore contamination of environmental substrates with xenobiotic chemicals. The substrates in question, fish tissue, human seminal plasm...

  9. Peering Into the Shadows of Chemical Space. Emerging Contaminants and Environmental Science: Is Either Being Served by the Other?

    EPA Science Inventory

    A decade has passed since the term emerging was first formally used to describe the existence of waterpollutants not previously recognized; a 1998 NRC workshop ("Identifying Future Drinking WaterContaminants") and several 1999 reports by USGS were among the first to feature the...

  10. Peering Into the Shadows of Chemical Space. Emerging Contaminants and Environmental Science: Is Either Being Served by the Other?

    EPA Science Inventory

    A decade has passed since the term “emerging” was first formally used to describe the existence of waterpollutants not previously recognized; a 1998 NRC workshop ("Identifying Future Drinking WaterContaminants") and several 1999 reports by USGS were among the first to feature the...

  11. Environmental contaminants and intestinal function

    PubMed Central

    Banwell, John G.

    1979-01-01

    The environmental contaminants which have their major effects on the small intestine may be classified into five major categories: (1) bacterial, viral, and parasitic agents, (2) food and plant substances, (3) environmental and industrial products, (4) pharmaceutical agents, and (5) toxic agents whose metabolic effects are dependent on interreaction with intestinal bacterial flora, other physical agents (detergents), human intestinal enzyme deficiency states, and the nutritional state of the host. Bacterial, viral, and parasitic agents are the most important of all such agents, being responsible for significant mortality and morbidity in association with diarrheal diseases of adults and children. Several plant substances ingested as foods have unique effects on the small bowel as well as from contaminants such as fungi on poorly preserved grains and cereals. Environmental and industrial products, in spite of their widespread prevalence in industrial societies as contaminants, are less important unless unexpectedly intense exposure occurs to the intestinal tract. Pharmaceutical agents of several types interreact with the small bowel mucosa causing impairment of transport processes for fluid and electrolytes, amino acid, lipid and sugars as well as vitamins. These interreactions may be dependent on bacterial metabolic activity, association with detergents, mucosal enzyme deficiency state (disaccharidases), and the state of nutrition of the subject. PMID:540611

  12. Chemical contamination of water supplies

    SciTech Connect

    Shy, C.M.

    1985-10-01

    Man-made organic chemicals have been found in drinking water for many years. Their numbers and varieties increase as our analytical capabilities improve. The identified chemicals comprise 10 to 20% of the total organic matter present. These are volatile or low molecular weight compounds which are easily identified. Many of them are carcinogenic or mutagenic. Chlorinated compounds have been found in untreated well water at levels up to 21,300 micrograms/L and are generally present at higher levels in chlorine-treated water than in untreated water. Aggregate risk studies for cancer are summarized. The most common sites are: bladder, stomach, colon, and rectum. Such studies cannot be linked to individual cases. However, they are useful for identifying exposed populations for epidemiologic studies. Five case-control studies were reviewed, and significant associations with water quality were found for: bladder cancer in two studies, colon cancer in three and rectal cancer in four. A large study by the National Cancer Institute found that there had been a change in the source of raw water for 50% of the persons in one area between the years 1955 and 1975. Such flaws in the data may preclude finding a causal relation between cancer and contaminants in drinking water. Large case-control and cohort studies are needed because of the low frequency of the marker diseases, bladder and rectal cancer. Cohort studies may be precluded by variations in the kinds of water contaminants. Definitive questions about these issues are posed for cooperative effort and resolution by water chemists, engineers, and epidemiologists.

  13. Environmental Geochemistry of Radioactive Contamination

    NASA Astrophysics Data System (ADS)

    Siegel, M. D.; Bryan, C. R.

    2003-12-01

    Psychometric studies of public perception of risk have shown that dangers associated with radioactive contamination are considered the most dreaded and among the least understood hazards (Slovic, 1987). Fear of the risks associated with nuclear power and associated contamination has had important effects on policy and commercial decisions in the last few decades. In the US, no new nuclear power plants were ordered between 1978 and 2002, even though it has been suggested that the use of nuclear power has led to significantly reduced CO2 emissions and may provide some relief from the potential climatic changes associated with fossil fuel use. The costs of the remediation of sites contaminated by radioactive materials and the projected costs of waste disposal of radioactive waste in the US dwarf many other environmental programs. The cost of disposal of spent nuclear fuel at the proposed repository at Yucca Mountain will likely exceed 10 billion. The estimated total life cycle cost for remediation of US Department of Energy (DOE) weapons production sites ranged from 203-247 billion dollars in constant 1999 dollars, making the cleanup the largest environmental project on the planet (US DOE, 2001). Estimates for the cleanup of the Hanford site alone exceeded $85 billion through 2046 in some of the remediation plans.Policy decisions concerning radioactive contamination should be based on an understanding of the potential migration of radionuclides through the geosphere. In many cases, this potential may have been overestimated, leading to decisions to clean up contaminated sites unnecessarily and exposing workers to unnecessary risk. It is important for both the general public and the scientific community to be familiar with information that is well established, to identify the areas of uncertainty and to understand the significance of that uncertainty to the assessment of risk.

  14. Chemical sensors for environmental monitoring

    NASA Astrophysics Data System (ADS)

    Tabacco, Mary B.; Zhou, Quan; Nelson, Bruce N.

    1992-03-01

    Fiber optic chemical sensors are being developed for on-line monitoring of gases and liquids. The sensors utilize novel porous polymer or glass optical fibers in which selective chemical reagents have been immobilized. These reagents react with the analyte of interest resulting in a change in the optical properties of the sensor. These sensors (or optrodes) are particularly suited to in-situ detection of atmospheric trace contaminants and dissolved gases and chemicals, as may be required for environmental monitoring. Sensors have been demonstrated for low part-per-billion level detection of aromatic hydrocarbons, hydrazines and ethylene. Sensors have also been demonstrated for carbon monoxide ammonia, and humidity. Also, relevant to groundwater monitoring is the development of an integrated pH optrode system for the pH range 4 - 8, with additional optrodes for lower pH ranges.

  15. Epigenetics and environmental chemicals

    PubMed Central

    Baccarelli, A; Bollati, V.

    2011-01-01

    Purpose of the review Epigenetics investigates heritable changes in gene expression occurring without changes in DNA sequence. Several epigenetic mechanisms, including DNA methylation, histone modifications, and microRNA (miRNA) expression, can change genome function under exogenous influence. Here, we review current evidence indicating that epigenetic alterations mediate toxicity from environmental chemicals. Recent findings In-vitro, animal, and human investigations have identified several classes of environmental chemicals that modify epigenetic marks, including metals (cadmium, arsenic, nickel, chromium, methylmercury), peroxisome proliferators (trichloroethylene, dichloroacetic acid, trichloroacetic acid), air pollutants (particulate matter, black carbon, benzene), and endocrine-disrupting/reproductive toxicants (diethylstilbestrol, bisphenol A, persistent organic pollutants, dioxin). Most studies conducted so far have been centered on DNA methylation, whereas only a few investigations have studied environmental chemicals in relation to histone modications and miRNA. Summary For several exposures, it has been proved that chemicals can alter epigenetic marks and that the same or similar epigenetic alterations can be found in patients with the disease of concern or in diseased tissues. Future prospective investigations are needed to determine whether exposed subjects develop epigenetic alterations over time and, in turn, which such alterations increase the risk of disease. Also, further research is needed to determine whether environmental epigenetic changes are transmitted transgenerationally. PMID:19663042

  16. Environmental contaminants in California condors

    USGS Publications Warehouse

    Wiemeyer, Stanley N.; Scott, J.M.; Anderson, M.P.; Bloom, P.H.; Stafford, C.J.

    1988-01-01

    Five wild Califorinia condors (Gymnogyps californianus) that died in 1980-86 were necropsied and tissues were analyzed for environmental contaminants. Three died of lead (Pb) poisoning, 1 presumably of cyanide (CN) poisoning, and 1 nestling of handling shock. Organochlorine concentrations were low in 4 condors that were analyzed for these contaminants. Blood samples from 14 wild and 14 captive condors were analyzed primarily for Pb. Five of 14 wild condors sampled had elevated (> 0.70 ppm) concentrations of Pb in blood whereas Pb concentrations in all captive condors were low. Lead levels in individual birds often fluctuated over time. Lead exposure, especially poisoning, was a major factor affecting the wild California condor population during 1982-86. The probable source of Pb was bullet fragments in carrion on which condors were feeding.

  17. Environmental contaminants in Canadian shorebirds.

    PubMed

    Braune, Birgit M; Noble, David G

    2009-01-01

    Canadian shorebirds are exposed to environmental contaminants throughout their annual cycle. Contaminant exposure among species varies with diet, foraging behaviour and migration patterns. We sampled twelve species of shorebirds from four locations across Canada to assess their exposure to PCBs, organochlorine pesticides, as well as four trace elements (Hg, Se, Cd, As). SigmaPCB and SigmaDDT followed by SigmaCHL were most frequently found above trace level in the shorebird carcasses. In general, the plover species (American golden, semipalmated, black-bellied) appear to be the most contaminated with organochlorines, whereas Hudsonian and marbled godwits appear to be the least contaminated. Among adult birds, the greater and lesser yellowlegs had the highest hepatic Hg concentrations (2.4-2.7 microg g(-1) dw), whereas American golden plovers as well as Hudsonian and marbled godwits contained relatively low levels of Hg (<1 microg g(-1) dw). Renal Se concentrations varied from 3.2 to 16.7 microg g(-1) dw and exhibited little interspecific or seasonal variation. Renal Cd levels in adult birds were highest in Hudsonian godwits from Quill Lakes (43 microg g(-1) dw) and Cape Churchill (12 microg g(-1) dw), and lowest (0.8-1.5 microg g(-1) dw) in greater and lesser yellowlegs from Cape Churchill and Bay of Fundy. Renal As concentrations varied from 0.06 microg g(-1) dw in golden plovers from Cape Churchill to 4.6 and 5.1 microg g(-1) dw in dunlin samples from the Pacific coast. There is no evidence that contaminants were adversely affecting the shorebirds sampled from the Canadian locations in this study. PMID:18340543

  18. Control of chemical contaminants in foods: past, present, and future

    SciTech Connect

    Jelinek, C.F.

    1985-11-01

    In the late 1930s and early 1940s, almost the only analyses carried out for chemical contaminants in foods were for lead arsenate and other arsenical pesticides in fruits. Since then, a tremendous expansion has occurred in the types of chemical contaminants found in foods and in the activities of the U.S. Food and Drug Administration and other organizations responsible for monitoring and controlling the presence of these contaminants in the food supply. This paper describes the findings and control of additional chemical contaminants in foods, including synthetic pesticides, PCBs (polychlorinated biphenyls), other industrial chemicals, fungal metabolites such as aflatoxins, toxic metals, and radionuclides. The common characteristics of problems connected with these different types of contaminants include uncontrolled entry into the food supply, incidents causing extreme public worry, and near impossibility in removing these contaminants from the food supply. Problems may also arise from new technologies and environmental developments. New approaches beyond ordinary regulatory activities are being used to meet these problems. Broader analytical methods requiring less time and faster and more sophisticated toxicological methods are needed to assess the hazard of these environmental food contaminants.

  19. Chemical-gene interaction networks and causal reasoning for biological effects prediction and prioritization of contaminants for environmental monitoring and surveillance

    EPA Science Inventory

    Evaluating the potential human health and ecological risks associated with exposures to complex chemical mixtures in the environment is one of the main challenges of chemical safety assessment and environmental protection. There is a need for approaches that can help to integrat...

  20. CHILDREN'S DIETARY EXPOSURES TO CHEMICAL CONTAMINANTS

    EPA Science Inventory

    The Food Quality Protection Act of 1996 requires EPA to more accurately assess children's aggregate exposures to environmental contaminants. Children have unstructured eating behaviors which cause excess exposures as a result of their activities. Determining total dietary intak...

  1. DEVELOPMENTS IN CHEMICAL TREATMENT OF CONTAMINATED SOIL

    EPA Science Inventory

    The U.S. Environmental Protection Agency's Office of Research and Development (ORD) is examining processes for remedial action at Superfund sites, and corrective action at operating disposal sites. ecent legislation emphasizes destruction and detoxification of contaminants, rathe...

  2. A new multimedia contaminant fate model for China: how important are environmental parameters in influencing chemical persistence and long-range transport potential?

    PubMed

    Zhu, Ying; Price, Oliver R; Tao, Shu; Jones, Kevin C; Sweetman, Andy J

    2014-08-01

    We present a new multimedia chemical fate model (SESAMe) which was developed to assess chemical fate and behaviour across China. We apply the model to quantify the influence of environmental parameters on chemical overall persistence (POV) and long-range transport potential (LRTP) in China, which has extreme diversity in environmental conditions. Sobol sensitivity analysis was used to identify the relative importance of input parameters. Physicochemical properties were identified as more influential than environmental parameters on model output. Interactive effects of environmental parameters on POV and LRTP occur mainly in combination with chemical properties. Hypothetical chemicals and emission data were used to model POV and LRTP for neutral and acidic chemicals with different KOW/DOW, vapour pressure and pKa under different precipitation, wind speed, temperature and soil organic carbon contents (fOC). Generally for POV, precipitation was more influential than the other environmental parameters, whilst temperature and wind speed did not contribute significantly to POV variation; for LRTP, wind speed was more influential than the other environmental parameters, whilst the effects of other environmental parameters relied on specific chemical properties. fOC had a slight effect on POV and LRTP, and higher fOC always increased POV and decreased LRTP. Example case studies were performed on real test chemicals using SESAMe to explore the spatial variability of model output and how environmental properties affect POV and LRTP. Dibenzofuran released to multiple media had higher POV in northwest of Xinjiang, part of Gansu, northeast of Inner Mongolia, Heilongjiang and Jilin. Benzo[a]pyrene released to the air had higher LRTP in south Xinjiang and west Inner Mongolia, whilst acenaphthene had higher LRTP in Tibet and west Inner Mongolia. TCS released into water had higher LRTP in Yellow River and Yangtze River catchments. The initial case studies demonstrated that SESAMe performed well on comparing POV and LRTP of chemicals in different regions across China in order to potentially identify the most sensitive regions. This model should not only be used to estimate POV and LRTP for screening and risk assessments of chemicals, but could potentially be used to help design chemical monitoring programmes across China in the future. PMID:24791706

  3. Chemical contaminants, pharmacokinetics, and the lactating mother.

    PubMed Central

    Rogan, W J; Ragan, N B

    1994-01-01

    We review the commonly occurring persistent pesticides and industrial chemicals in breast milk. These chemicals are dichlorodiphenyl trichloroethane as dichlorodiphenyl dichloroethene dieldrin, chlordane as oxychlordane, heptachlor, polychlorinated biphenyls, polychlorinated dibenzofurans, and polychlorinated dibenzodioxins. We present a worked example of the kinds of pharmacokinetic assumptions and calculations necessary for setting regulatory limits of contaminants in the food supply, calculating dose of chemical contaminants to the nursed infant, converting risks from lifetime exposure in laboratory animals to risks for short-term exposure in humans, and estimating the excess cancer risk to the nursed infant. PMID:7737048

  4. Chemical Contamination of California Drinking Water

    PubMed Central

    Russell, Hanafi H.; Jackson, Richard J.; Spath, David P.; Book, Steven A.

    1987-01-01

    Drinking water contamination by toxic chemicals has become widely recognized as a public health concern since the discovery of 1,2-dibromo-3-chloropropane in California's Central Valley in 1979. Increased monitoring since then has shown that other pesticides and industrial chemicals are present in drinking water. Contaminants of drinking water also include naturally occurring substances such as asbestos and even the by-products of water chlorination. Public water systems, commercially bottled and vended water and mineral water are regulated, and California is also taking measures to prevent water pollution by chemicals through various new laws and programs. PMID:3321714

  5. Environmental contamination due to shale gas development.

    PubMed

    Annevelink, M P J A; Meesters, J A J; Hendriks, A J

    2016-04-15

    Shale gas development potentially contaminates both air and water compartments. To assist in governmental decision-making on future explorations, we reviewed scattered information on activities, emissions and concentrations related to shale gas development. We compared concentrations from monitoring programmes to quality standards as a first indication of environmental risks. Emissions could not be estimated accurately because of incomparable and insufficient data. Air and water concentrations range widely. Poor wastewater treatment posed the highest risk with concentrations exceeding both Natural Background Values (NBVs) by a factor 1000-10,000 and Lowest Quality Standards (LQSs) by a factor 10-100. Concentrations of salts, metals, volatile organic compounds (VOCs) and hydrocarbons exceeded aquatic ecotoxicological water standards. Future research must focus on measuring aerial and aquatic emissions of toxic chemicals, generalisation of experimental setups and measurement technics and further human and ecological risk assessment. PMID:26845179

  6. Environmental Chemicals in Breast Milk

    EPA Science Inventory

    Most of the information available on environmental chemicals in breast milk is focused on persistent, lipophilic chemicals; the database on levels of these chemicals has expanded substantially since the 1950s. Currently, various types of chemicals are measured in breast milk and ...

  7. Environmental forensic research for emerging contaminants in complex environmental matrices

    EPA Science Inventory

    The United States Environmental Protection Agency has established criteria to address many of the significant traditional pollutants demonstrated to have adverse affects on environmental quality. However, new chemicals are being created almost daily, and these new chemicals, as ...

  8. ENVIRONMENTAL MASS SPECTROMETRY: EMERGING CONTAMINANTS AND CURRENT ISSUES

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise. This presentation will discuss chemical and microbial contaminants that the U.S. EPA and other agencies are currently concerned about. In this gr...

  9. EMERGING ENVIRONMENTAL CONTAMINANTS AND CURRENT ISSUES, MEETING IN SEATTLE, WA

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise. This presentation will discuss chemical and microbial contaminants that the U.S. EPA and other agencies are currently concerned about. In this gr...

  10. BIOASSAY-DIRECTED CHEMICAL ANALYSIS IN ENVIRONMENTAL RESEARCH

    EPA Science Inventory

    The use of short-term bioassay tests in conjunction with analytical measurements, constitute a powerful tool for identifying important environmental contaminants. The authors have coined the terminology 'bioassay directed chemical analysis' to best describe this marriage of analy...

  11. Reviews of environmental contamination and toxicology

    SciTech Connect

    Ware, G.W. )

    1990-01-01

    This book contains review articles concerned with all aspects of chemical contaminants (including pesticides) in the total environment, particularly toxicological considerations and consequences. It provided reviews of advances, philosophy, and significant areas of accomplished or needed endeavor in the total field of residues of these and other foreign chemicals in any segment of the environment, as well as toxicological implications.

  12. EMERGING ENVIRONMENTAL CONTAMINANTS AND CURRENT ISSUES

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise. This presentation will discuss emerging environmental contaminants that the U.S. EPA and other agencies are currently concerned about. Emerging c...

  13. The epidemiology of chemical contaminants of drinking water.

    PubMed

    Calderon, R L

    2000-01-01

    A number of chemical contaminants have been identified in drinking water. These contaminants reach drinking water supplies from various sources, including municipal and industrial discharges, urban and rural run-off, natural geological formations, drinking water distribution materials and the drinking water treatment process. Chemical contaminants for which epidemiologic studies have reported associations include the following: aluminium, arsenic, disinfection by-products, fluoride, lead, pesticides and radon. Health effects reported have included various cancers, adverse reproductive outcomes, cardiovascular disease and neurological disease. In evaluating epidemiologic studies for risk assessment, considering whether the study design was qualitative (hypothesis generating) or quantitative (hypothesis testing) is important and whether sufficient epidemiologic data of a quantitative nature exists to determine the dose-response curve. Each of the chemical contaminants mentioned are summarized by study designs (qualitative and quantitative) and whether a dose-response curve based on epidemiologic data has been proposed. Environmental epidemiology studies are driven by environmental exposures of interest. For drinking water contaminants, the design of epidemiologic studies and their interpretation should consider the following exposure issues: the source of the contaminant; other sources of the contaminant; the route of exposure; the frequency, duration and magnitude of exposure; the ability to document an actual internal dose; and the ability to document the dose to the target organ. Health effects of concern have other risk factors that must be measured in the conduct of these studies. In evaluating epidemiologic studies, potential errors and biases that may occur must be considered given the very low magnitude of associations (less than 2.0 for either odds ratio or risk ratio). Given the issues, the next generation of drinking water epidemiologic studies should include a multidisciplinary team beyond traditional epidemiologists and statisticians. Study teams will require toxicologists, chemists, engineers and exposure assessors. Arsenic is briefly discussed as an example of the importance of susceptible populations. Disinfection by-products are discussed as an example of epidemiologic studies of mixtures. PMID:10717366

  14. Intentional and inadvertent chemical contamination of food, water, and medication.

    PubMed

    MCKay, Charles; Scharman, Elizabeth J

    2015-02-01

    Numerous examples of chemical contamination of food, water, or medication have led to steps by regulatory agencies to maintain the safety of this critical social infrastructure and supply chain. Identification of contaminant site is important. Environmental testing and biomonitoring can define the nature and extent of the event and are useful for providing objective information, but may be unavailable in time for clinical care. Clinical diagnosis should be based on toxidrome recognition and assessment of public health implications. There are several resources available to assist and these can be accessed through regional poison control centers or local/state public health departments. PMID:25455667

  15. The Toxicity Data Landscape for Environmental Chemicals

    PubMed Central

    Judson, Richard; Richard, Ann; Dix, David J.; Houck, Keith; Martin, Matthew; Kavlock, Robert; Dellarco, Vicki; Henry, Tala; Holderman, Todd; Sayre, Philip; Tan, Shirlee; Carpenter, Thomas; Smith, Edwin

    2009-01-01

    Objective Thousands of chemicals are in common use, but only a portion of them have undergone significant toxicologic evaluation, leading to the need to prioritize the remainder for targeted testing. To address this issue, the U.S. Environmental Protection Agency (EPA) and other organizations are developing chemical screening and prioritization programs. As part of these efforts, it is important to catalog, from widely dispersed sources, the toxicology information that is available. The main objective of this analysis is to define a list of environmental chemicals that are candidates for the U.S. EPA screening and prioritization process, and to catalog the available toxicology information. Data sources We are developing ACToR (Aggregated Computational Toxicology Resource), which combines information for hundreds of thousands of chemicals from > 200 public sources, including the U.S. EPA, National Institutes of Health, Food and Drug Administration, corresponding agencies in Canada, Europe, and Japan, and academic sources. Data extraction ACToR contains chemical structure information; physical–chemical properties; in vitro assay data; tabular in vivo data; summary toxicology calls (e.g., a statement that a chemical is considered to be a human carcinogen); and links to online toxicology summaries. Here, we use data from ACToR to assess the toxicity data landscape for environmental chemicals. Data synthesis We show results for a set of 9,912 environmental chemicals being considered for analysis as part of the U.S. EPA ToxCast screening and prioritization program. These include high-and medium-production-volume chemicals, pesticide active and inert ingredients, and drinking water contaminants. Conclusions Approximately two-thirds of these chemicals have at least limited toxicity summaries available. About one-quarter have been assessed in at least one highly curated toxicology evaluation database such as the U.S. EPA Toxicology Reference Database, U.S. EPA Integrated Risk Information System, and the National Toxicology Program. PMID:19479008

  16. Environmental contamination by canine geohelminths

    PubMed Central

    2014-01-01

    Intestinal nematodes affecting dogs, i.e. roundworms, hookworms and whipworms, have a relevant health-risk impact for animals and, for most of them, for human beings. Both dogs and humans are typically infected by ingesting infective stages, (i.e. larvated eggs or larvae) present in the environment. The existence of a high rate of soil and grass contamination with infective parasitic elements has been demonstrated worldwide in leisure, recreational, public and urban areas, i.e. parks, green areas, bicycle paths, city squares, playgrounds, sandpits, beaches. This review discusses the epidemiological and sanitary importance of faecal pollution with canine intestinal parasites in urban environments and the integrated approaches useful to minimize the risk of infection in different settings. PMID:24524656

  17. Owls as biomonitors of environmental contamination

    SciTech Connect

    Sheffield, S.R.

    1995-12-31

    Exposure and effects of environmental contaminants on owls has been largely understudied. Research primarily has focused on two species, the eastern screech owl (Otus asio) and barn owl (Tyto alba). Most of this work has been conducted with captive populations at the Patuxent Wildlife Research Center in Laurel, MD. In the wild, work has been, or is currently being, conducted with great-horned owls (Bubo virginianus) at a Superfund site in Colorado and in agricultural croplands in Iowa, and barn owls at a Superfund site in Texas and in metal-contaminated regions of the Netherlands. As higher order consumers, owls bioconcentrate many different environmental contaminants through their prey. Owls have proven to be sensitive to a wide variety of toxic compounds, including PCB`s, metals, and fluoride. Endpoints examined include reproductive effects, eggshell thickness, residue analyses, cholinesterase inhibition, and induction of liver MFO`s. Much more work remains to be done using owls as biomonitors of environmental contamination, particularly with captive populations, salvaged individuals, raptor rehabilitation center birds, and with wild populations in areas around hazardous waste sites, smelters, landfills, agricultural croplands, and other major sources of environmental contamination.

  18. Environmental impact of mining activities in the Lousal area (Portugal): chemical and diatom characterization of metal-contaminated stream sediments and surface water of Corona stream.

    PubMed

    Lus, Ana Teresa; Teixeira, Paula; Almeida, Salom Fernandes Pinheiro; Matos, Joo Xavier; da Silva, Eduardo Ferreira

    2011-09-15

    Lousal mine is a typical "abandoned mine" with all sorts of problems as consequence of the cessation of the mining activity and lack of infrastructure maintenance. The mine is closed at present, but the heavy metal enriched tailings remain at the surface in oxidizing conditions. Surface water and stream sediments revealed much higher concentrations than the local geochemical background values, which the "Contaminated Sediment Standing Team" classifies as very toxic. High concentrations of Cu, Pb, Zn, As, Cd and Hg occurred within the stream sediments downstream of the tailings sites (up to: 817 mg kg(-1) As, 6.7 mg kg(-1) Cd, 1568 mg kg(-1) Cu, 1059 mg kg(-1) Pb, 82.4 mg kg(-1) Sb, 4373 mg kg(-1) Zn). The AMD waters showed values of pH ranging from 1.9 to 2.9 and concentrations of 9249 to 20,700 mg L(-1) SO(4)(-2), 959 to 4830 mg L(-1) Fe and 136 to 624 mg L(-1) Al. Meanwhile, the acid effluents and mixed stream waters also carried high contents of SO(4)(2-,) Fe, Al, Cu, Pb, Zn, Cd, and As, generally exceeding the Fresh Water Aquatic Life Acute Criteria. Negative impacts in the diatom communities growing at different sites along a strong metal pollution gradient were shown through Canonical Correspondence Analysis: in the sites influenced by Acid Mine Drainage (AMD), the dominant taxon was Achnanthidium minutissimum. However, Pinnularia acoricola was the dominant species when the environmental conditions were extremely adverse: very low pH and high metal concentrations (sites 2 and 3). Teratological forms of Achnanthidium minutissimum (Ktzing) Czarnecki, Brachysira vitrea (Grunow) Ross in Hartley, Fragilaria rumpens (Ktzing) G. W. F. Carlson and Nitzschia hantzschiana Rabenhorst were found. A morphometric study of B. vitrea showed that a decrease in size was evident at the most contaminated sites. These results are evidence of metal and acidic pollution. PMID:21802708

  19. Seabird eggs as bioindicators of chemical contamination in Chile.

    PubMed

    Cifuentes, Jacqueline Muoz; Becker, Peter H; Sommer, Ute; Pacheco, Patricia; Schlatter, Roberto

    2003-01-01

    Seabird eggs were used as bioindicators of chemical contamination in Chile. Brown-hooded Gull (Larus maculipennis), Kelp Gull (Larus dominicanus), Trudeau's Tern (Sterna trudeaui), Neotropic Cormorant (Phalacrocorax brasilianus), and Pink-footed Shearwater (Puffinus creatopus) eggs were sampled at different breeding sites during the 1990s. Mercury and organochlorines (PCBs, DDT, HCB, HCH, and PCP) were quantified to reveal the interspecific differences, spatial and temporal trends in contamination levels. Trudeau's Tern displayed the highest levels of mercury (486 ng g(-1) wet weight). The highest sumDDT concentrations were measured in Brown-hooded Gulls (726 ng g(-1)). PCB levels were similar among the species (102-236 ng g(-1)), but the composition of the PCB mixture was different in Pink-footed Shearwaters. With the exception of the Brown-hooded Gull, all species studied presented similar and low levels of organochlorines (sumOHa). Residues of PCB and related compounds were not detected in any of the seabird eggs analyzed in Chile. Geographical variation was low, although levels of industrial chemicals were slightly higher in eggs from Concepcin Bay, and agricultural chemicals in eggs from Valdivia. Also interannual variation was low, but some evidence was found of decreasing levels in gull eggs throughout the time of the study. The causes of the low levels and small variability in space and time of environmental chemicals in Chilean seabirds are discussed. We propose the use of seabirds in future monitoring of the development of chemical contamination in Chile. PMID:12860109

  20. Reviews of environmental contamination and toxicology

    SciTech Connect

    Ware, G.W.

    1988-01-01

    This book contains timely review articles concerned with all aspects of chemical contaminants (including pesticides) in the total environment, including toxiological considerations and consequences. It attempts to provide concise, critical reviews of advances, philosophy, and significant areas of accomplished or needed endeavor in the total field of residues of these and other foreign chemicals in any segment of the environment, as well as toxicological implications.

  1. Bio-assays for microchemical environmental contaminants

    PubMed Central

    Warner, Richard E.

    1967-01-01

    A solution of the problem of environmental contamination must be based on accurate measurement of the extent of the contamination and of the resulting hazards. This paper reviews the methods for the estimation of microchemical contaminants in water with the aid of living organisms. The methods are grouped according to the nature of the response of the organism to the contaminant—namely, acute response (usually death), behavioural change, physiological change, biochemical and histochemical change, ecological change, embryological and regenerational change, growth change, histological change and perception by man or aquatic organisms. Finally, the following problems are discussed: selection of appropriate tests and standardization, the dangers of sequential concentration and the need for multi-parametric assays (assays involving several responses of a single organism, or responses of several organisms) for complete characterization of the effects of a contaminant on the environment. ImagesFIG. 2FIG. 3FIG. 4FIG. 5FIG. 6 PMID:5299747

  2. DERMAL AND GASTROINTESTINAL ABSORPTION OF ENVIRONMENTAL CONTAMINANTS

    EPA Science Inventory

    Hazards from environmental contaminants have become a necessary part of life in industrial countries. In the past few decades, a number of 'new' problems have arisen (termiticide-treated premises, reentry into pesticide-treated fields, acid rain, aldicarb in ground water, dioxins...

  3. Chemical contaminants in feedlot wastes: concentrations, effects and attenuation.

    PubMed

    Khan, S J; Roser, D J; Davies, C M; Peters, G M; Stuetz, R M; Tucker, R; Ashbolt, N J

    2008-08-01

    Commercial feedlots for beef cattle finishing are potential sources of a range of trace chemicals which have human health or environmental significance. To ensure adequate protection of human and environmental health from exposure to these chemicals, the application of effective manure and effluent management practices is warranted. The Australian meat and livestock industry has adopted a proactive approach to the identification of best management practices. Accordingly, this review was undertaken to identify key chemical species that may require consideration in the development of guidelines for feedlot manure and effluent management practices in Australia. Important classes of trace chemicals identified include steroidal hormones, antibiotics, ectoparasiticides, mycotoxins, heavy metals and dioxins. These are described in terms of their likely sources, expected concentrations and public health or environmental significance based on international data and research. Androgenic hormones such as testosterone and trenbolone are significantly active in feedlot wastes, but they are poorly understood in terms of fate and environmental implications. The careful management of residues of antibiotics including virginiamycin, tylosin and oxytetracycline appears prudent in terms of minimising the risk of potential public health impacts from resistant strains of bacteria. Good management of ectoparasiticides including synthetic pyrethroids, macrocyclic lactones, fluazuron, and amitraz is important for the prevention of potential ecological implications, particularly towards dung beetles. Very few of these individual chemical contaminants have been thoroughly investigated in terms of concentrations, effects and attenuation in Australian feedlot wastes. PMID:18055014

  4. Environmental contaminant exposures and preterm birth: A comprehensive review

    PubMed Central

    Ferguson, Kelly K.; O’Neill, Marie S.; Meeker, John D.

    2013-01-01

    Preterm birth is a significant public health concern, as it is associated with high risk of infant mortality, various morbidities in both the neonatal period and later in life, and a significant societal economic burden. As many cases are of unknown etiology, identification of the contribution of environmental contaminant exposures is a priority in the study of preterm birth. This is a comprehensive review of all known studies published from 1992 through August 2012 linking maternal exposure to environmental chemicals during pregnancy with preterm birth. Using PubMed searches studies were identified that examined associations between preterm birth and exposure to 5 categories of environmental toxicants, including persistent organic pollutants, drinking water contaminants, atmospheric pollutants, metals and metalloids, and other environmental contaminants. Individual studies were summarized and specific suggestions made for future work in regard to exposure and outcome assessment methods as well as study design, with the recommendation of focusing on potential mediating toxicological mechanisms. In conclusion, no consistent evidence was found for positive associations between individual chemical exposures and preterm birth. By identifying limitations and addressing the gaps that may have impeded the ability to identify true associations thus far, this review can guide future epidemiologic studies of environmental exposures and preterm birth. PMID:23682677

  5. Trace chemical contaminant generation rates for spacecraft contamination control system design

    NASA Technical Reports Server (NTRS)

    Perry, J. L.

    1995-01-01

    A spacecraft presents a unique design challenge with respect to providing a comfortable environment in which people can live and work. All aspects of the spacecraft environmental design including the size of the habitable volume, its temperature, relative humidity, and composition must be considered to ensure the comfort and health of the occupants. The crew members and the materials selected for outfitting the spacecraft play an integral part in designing a habitable spacecraft because material offgassing and human metabolism are the primary sources for continuous trace chemical contaminant generation onboard a spacecraft. Since these contamination sources cannot be completely eliminated, active control processes must be designed and deployed onboard the spacecraft to ensure an acceptably clean cabin atmosphere. Knowledge of the expected rates at which contaminants are generated is very important to the design of these processes. Data from past spacecraft missions and human contaminant production studies have been analyzed to provide this knowledge. The resulting compilation of contaminants and generation rates serve as a firm basis for past, present, and future contamination control system designs for space and aeronautics applications.

  6. Reconnaissance survey of chemical contamination and biological effects in southern Puget Sound

    SciTech Connect

    Not Available

    1991-04-01

    The report describes the results of a field survey south of the Tacoma Narrows bridge in southern Puget Sound. Environmental conditions were evaluated in two urban embayments, eight nonurban embayments and three areas of the main channel in the southern Sound. Stations were located in depositional areas where chemical contaminants would be expected to accumulate in the sediments. All stations were located away from known contaminant sources in order to provide integrative assessments of contamination over relatively large areas. Chemical contamination of the south Sound was evaluated by measuring chemical concentrations in subtidal bottom sediments. Bioaccumulation of chemical contaminants was evaluated by measuring chemical concentrations in flatfish muscle tissues and littleneck clam meats. Chemical-related biological effects were evaluated by conducting amphipod sediment bioassays and histopathological analyses on livers of English sole.

  7. Biodegradation of environmental contaminants using white rot fungi

    SciTech Connect

    White, R.B.; Aust, S.D. )

    1994-08-01

    White rot fungi are a common, naturally-occurring class of wood-degrading fungi that evolved to degrade lignin. Extensive research conducted since the early 1980s has shown that many of the same mechanisms used by the fungi for lignin degradation also promote the degradation of several carbon-based environmental contaminants. These contaminants include polycyclic aromatic hydrocarbons, pesticides, herbicides, wood preservatives, chlorinated solvents, PCBs, explosives, cyanide, dyes and others. The fungi use an extra-cellular, free-radical, nonspecific mode of degradation, which allows them to degrade both soluble and insoluble contaminants, whether they are absorbed or in solution. The extra-cellular substances secreted by the fungi include several enzymes (which catalyze the initial oxidation of contaminant molecules), hydrogen ions (to maintain a slightly acidic pH), electrons (to maintain a charge balance and to reduce contaminant through the breaking of chemical bonds), and the fungi secrete veratryl alcohol (a free-radical mediator that catalyzes reductions) and oxalate (an organic acid that is a highly effective reductant). Application of white rot fungi for the remediation of contaminated soils involves mixing fungal-inoculated substrates with the soil. The materials are moistened during mixing to provide an environment that is conducive to fungal growth. The soil/substrate mixture is then placed in a biocell and aerated to promote contaminant degradation. Case histories of bench-scale tests and field applications are presented.

  8. CELLULAR BIOAVAILABILITY OF NATURAL HORMONES AND ENVIRONMENTAL CONTAMINANTS AS A FUNCTION OF SERUM AND CYTOSOLIC BINDING FACTORS

    EPA Science Inventory

    Environmental contaminants have been reported to function as hormone mimics in various wildlife species. To investigate a potential mechanism for the interaction of contaminants with the endocrine system, we evaluated the cellular bioavailability of numerous chemicals. Hormone bi...

  9. Using model-based screening to help discover unknown environmental contaminants.

    PubMed

    McLachlan, Michael S; Kierkegaard, Amelie; Radke, Michael; Sobek, Anna; Malmvrn, Anna; Alsberg, Tomas; Arnot, Jon A; Brown, Trevor N; Wania, Frank; Breivik, Knut; Xu, Shihe

    2014-07-01

    Of the tens of thousands of chemicals in use, only a small fraction have been analyzed in environmental samples. To effectively identify environmental contaminants, methods to prioritize chemicals for analytical method development are required. We used a high-throughput model of chemical emissions, fate, and bioaccumulation to identify chemicals likely to have high concentrations in specific environmental media, and we prioritized these for target analysis. This model-based screening was applied to 215 organosilicon chemicals culled from industrial chemical production statistics. The model-based screening prioritized several recognized organosilicon contaminants and generated hypotheses leading to the selection of three chemicals that have not previously been identified as potential environmental contaminants for target analysis. Trace analytical methods were developed, and the chemicals were analyzed in air, sewage sludge, and sediment. All three substances were found to be environmental contaminants. Phenyl-tris(trimethylsiloxy)silane was present in all samples analyzed, with concentrations of ?50 pg m(-3) in Stockholm air and ?0.5 ng g(-1) dw in sediment from the Stockholm archipelago. Tris(trifluoropropyl)trimethyl-cyclotrisiloxane and tetrakis(trifluoropropyl)tetramethyl-cyclotetrasiloxane were found in sediments from Lake Mjsa at ?1 ng g(-1) dw. The discovery of three novel environmental contaminants shows that models can be useful for prioritizing chemicals for exploratory assessment. PMID:24869768

  10. Environmental contaminants as etiologic factors for diabetes.

    PubMed Central

    Longnecker, M P; Daniels, J L

    2001-01-01

    For both type 1 and type 2 diabetes mellitus, the rates have been increasing in the United States and elsewhere; rates vary widely by country, and genetic factors account for less than half of new cases. These observations suggest environmental factors cause both type 1 and type 2 diabetes. Occupational exposures have been associated with increased risk of diabetes. In addition, recent data suggest that toxic substances in the environment, other than infectious agents or exposures that stimulate an immune response, are associated with the occurrence of these diseases. We reviewed the epidemiologic data that addressed whether environmental contaminants might cause type 1 or type 2 diabetes. For type 1 diabetes, higher intake of nitrates, nitrites, and N-nitroso compounds, as well as higher serum levels of polychlorinated biphenyls have been associated with increased risk. Overall, however, the data were limited or inconsistent. With respect to type 2 diabetes, data on arsenic and 2,3,7,8-tetrachlorodibenzo-p-dioxin relative to risk were suggestive of a direct association but were inconclusive. The occupational data suggested that more data on exposure to N-nitroso compounds, arsenic, dioxins, talc, and straight oil machining fluids in relation to diabetes would be useful. Although environmental factors other than contaminants may account for the majority of type 1 and type 2 diabetes, the etiologic role of several contaminants and occupational exposures deserves further study. PMID:11744505

  11. Malignant mammary tumor in female dogs: environmental contaminants.

    PubMed

    Andrade, Fbio He; Figueiroa, Fernanda C; Bersano, Paulo Ro; Bissacot, Denise Z; Rocha, Noeme S

    2010-01-01

    Mammary tumors of female dogs have greatly increased in recent years, thus demanding rapid diagnosis and effective treatment in order to determine the animal survival. There is considerable scientific interest in the possible role of environmental contaminants in the etiology of mammary tumors, specifically in relation to synthetic chemical substances released into the environment to which living beings are either directly or indirectly exposed. In this study, the presence of pyrethroid insecticide was observed in adjacent adipose tissue of canine mammary tumor. High Precision Liquid Chromatography - HPLC was adapted to detect and identify environmental contaminants in adipose tissue adjacent to malignant mammary tumor in nine female dogs, without predilection for breed or age. After surgery, masses were carefully examined for malignant neoplastic lesions. Five grams of adipose tissue adjacent to the tumor were collected to detect of environmental contaminants. The identified pyrethroids were allethrin, cyhalothrin, cypermethrin, deltamethrin and tetramethrin, with a contamination level of 33.3%. Histopathology demonstrated six female dogs (66.7%) as having complex carcinoma and three (33.3%) with simple carcinoma. From these tumors, seven (77.8%) presented aggressiveness degree III and two (22.2%) degree I. Five tumors were positive for estrogen receptors in immunohistochemical analysis. The contamination level was observed in more aggressive tumors. This was the first report in which the level of environmental contaminants could be detected in adipose tissue of female dogs with malignant mammary tumor, by HPLC. Results suggest the possible involvement of pyrethroid in the canine mammary tumor carcinogenesis. Hence, the dog may be used as a sentinel animal for human breast cancer, since human beings share the same environment and basically have the same eating habits. PMID:20587072

  12. Contamination by persistent chemicals in food chain and human health.

    PubMed

    Bro-Rasmussen, F

    1996-09-01

    Persistent polluting chemicals are, by definition, substances which have long half-lives or disappearance rates in the environment, mainly due to their chemical stability, but often also caused by unfavourable conditions for environmental/biological mineralisation processes to take place. DDT, lindane, dieldrin, HCB, and PCB are well known examples of chemicals which can be found in various parts/compartments of the environment, and in living organisms including man. The early findings in 1950s and 1960s of the persistent chlorinated pesticides in birds and fish populations in North America and Europe were obviously the results of deliberate and extensive use of these chemicals in agriculture and industry. The findings were confirmed and substantiated by national and international monitoring programmes, and it became clear that many field observations of threatened species convincingly could be correlated to the increasing levels of contamination. Still more man-made chemicals have been drawn into the field of interests as widespread pollutants, and the geographical areas in which contamination takes place have become ever larger. The threat to groundwater resources from infiltration of pesticides into soils, and the alarming reports on contamination of mothers milk are to-day well-known examples. They are described from many parts of the world. Similarly, the food chain biomagnification of several pesticides and of PCB which were already described from Great Lakes region in North America in the 1960s and from the Baltic Sea area in Europe in the 1970s has since then been followed by identical observations in the Danube basin in Eastern Europe and in Indian provinces during the 1980s. Scientifically, we are to-day able to describe many of the fundamental processes, including environmental transport and transformation, as well as exposure, uptake and metabolic patterns for many of the persistent man-made chemicals. Accordingly, we are reasonably well informed of the most obvious cause-effect chains which govern the process of increasing pollution. We understand and can often for most of the chemicals predict the hazards of the environment as well as to man. In spite of this experience, and contrary to belief created by our scientific knowledge, the problem of contamination is still increasing. This includes the frequency of reported accidents and damages from all over the world. It is obvious, therefore, that the question becomes a matter of concern for the global society and a call for world-wide attention through international bodies develops into a matter of urgency. PMID:8888628

  13. Environmental benefits of chemical propulsion

    NASA Technical Reports Server (NTRS)

    Hayes, Joyce A.; Goldberg, Benjamin E.; Anderson, David M.

    1995-01-01

    This paper identifies the necessity of chemical propulsion to satellite usage and some of the benefits accrued through monitoring global resources and patterns, including the Global Climate Change Model (GCM). The paper also summarized how the satellite observations are used to affect national and international policies. Chemical propulsion, like all environmentally conscious industries, does provide limited, controlled pollutant sources through its manufacture and usage. However, chemical propulsion is the sole source which enables mankind to launch spacecraft and monitor the Earth. The information provided by remote sensing directly affects national and international policies designed to protect the environment and enhance the overall quality of life on Earth. The resultant of chemical propulsion is the capability to reduce overall pollutant emissions to the benefit of mankind.

  14. Chemical contaminants in breast milk: time trends and regional variability.

    PubMed

    Solomon, Gina M; Weiss, Pilar M

    2002-06-01

    Research on environmentally related chemical contaminants in breast milk spans several decades and dozens of countries. The ability to use this research as an environmental indicator is limited because of a lack of consistent protocols. Data on xenobiotics in breast milk are influenced by choices in sample selection, sample pooling, analysis, and reporting. In addition, most studies have focused only on a small panel of persistent organic pollutants, despite indications that a wide range of additional chemical contaminants may also enter breast milk. Despite these limitations, however, it is possible to draw some generalizations. In this paper we review available data on levels of organochlorine pesticides, polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins (PCDDs), polybrominated diphenyl ethers (PBDEs), metals, and solvents in breast milk. Examples drawn from around the world illustrate the available data and the patterns that have appeared in various areas over time. Over the past few decades, levels of the organochlorine pesticides, PCBs, and dioxins have declined in breast milk in countries where these chemicals have been banned or otherwise regulated. In contrast, the levels of PBDEs are rising. Regional differences in levels of xenobiotics in breast milk are related to historical and current local use patterns. Diet is a major factor that influences breast milk levels of persistent organic pollutants, with patterns in fish consumption playing a particularly significant role. Improved global breast milk monitoring programs would allow for more consistent data on trends over time, detection of new xenobiotics in breast milk, and identification of disproportionately exposed populations. PMID:12055065

  15. Chemical contaminants in breast milk: time trends and regional variability.

    PubMed Central

    Solomon, Gina M; Weiss, Pilar M

    2002-01-01

    Research on environmentally related chemical contaminants in breast milk spans several decades and dozens of countries. The ability to use this research as an environmental indicator is limited because of a lack of consistent protocols. Data on xenobiotics in breast milk are influenced by choices in sample selection, sample pooling, analysis, and reporting. In addition, most studies have focused only on a small panel of persistent organic pollutants, despite indications that a wide range of additional chemical contaminants may also enter breast milk. Despite these limitations, however, it is possible to draw some generalizations. In this paper we review available data on levels of organochlorine pesticides, polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins (PCDDs), polybrominated diphenyl ethers (PBDEs), metals, and solvents in breast milk. Examples drawn from around the world illustrate the available data and the patterns that have appeared in various areas over time. Over the past few decades, levels of the organochlorine pesticides, PCBs, and dioxins have declined in breast milk in countries where these chemicals have been banned or otherwise regulated. In contrast, the levels of PBDEs are rising. Regional differences in levels of xenobiotics in breast milk are related to historical and current local use patterns. Diet is a major factor that influences breast milk levels of persistent organic pollutants, with patterns in fish consumption playing a particularly significant role. Improved global breast milk monitoring programs would allow for more consistent data on trends over time, detection of new xenobiotics in breast milk, and identification of disproportionately exposed populations. PMID:12055065

  16. SUITABILITY OF CUNNER (TAUTOGOLABRUS ADSPERSUS) FOR INVESTIGATING REPRODUCTIVE EFFECTS OF ENVIRONMENTAL CONTAMINANTS

    EPA Science Inventory

    Cunner (Tautogolabrus adspersus) are being studied at our laboratory as a model species to determine the effects of environmental contaminants, such as endocrine disrupting chemicals (EDCs), on estuarine fish populations. Cunner are easily obtainable and are amenable to laborator...

  17. THE EPIDEMIOLOGY OF CHEMICAL CONTAMINANTS OF DRINKING WATER

    EPA Science Inventory



    A number of chemical contaminants have been identified in drinking water. These contaminants reach drinking water supplies from various sources, including municipal and industrial discharges, urban and rural run-off, natural geological formations, drinking water distrib...

  18. Chemical Agents: Personal Cleaning and Disposal of Contaminated Clothing

    MedlinePLUS

    ... At-Risk Populations Chemical Agents: Facts About Personal Cleaning and Disposal of Contaminated Clothing Format: Select one ... How you can get more information about personal cleaning and disposal of contaminated clothing You can contact ...

  19. Environmental chemistry of chemical warfare agents

    SciTech Connect

    MacNaughton, M.G.; Brewer, J.H.; Ledbetter-Ferrill, J.

    1995-06-01

    This paper summarizes the approach used in the preparation of a Handbook for the Corps of Engineers, Huntsville Division, on the environmental chemistry of chemical warfare agents. The agents GB and HD will be used to illustrate the type of information in the report. Those readers interested in the full report should contact Mr. Arkie Fanning, Huntsville Corps of Engineers at (505) 955-5256. The U.S. Army Corps of Engineers (ACE) has identified approximately 7,200 formerly used defense sites (FUDS) in the United States, some of which are suspected to be contaminated with chemical warfare agents (CWA). The ACE has responsibility for environmental clean-up of FUDS, including site characterization, evaluation and remediation of the site. Thirty-four FUDS and 48 active DOD installations that may contain CWA were identified in an Interim Survey and Analysis Report by the USACMDA Program Manager for Non-Stockpile Chemical Material (NSCM). The chemical agents listed include sulfur mustard (H), lewisite (L), tabun (GA), sarin (GB), VX, hydrogen cyanide (AC), cyanogen chloride (CK), phosgene (CG), BZ, and CS.

  20. Environmental remediation monitoring using chemical sensors

    SciTech Connect

    Dong X. Li

    1996-12-31

    Monitoring is one of the most critical steps in environmental site remediation. However, the conventional technique of monitoring {open_quotes}inlet{close_quotes} and {open_quotes}outlet{close_quotes} of a process stream is no longer applicable in many in-situ remedial processes such as bioventing, biosparging, and intrinsic bioremediation. Traditional soil sampling and analysis is also unsuitable for monitoring biodegradation process because of chemical and biological inhomogeneity in soil. Soil gas measurement, on the other hand, is one of the few techniques available which is ideally suited for monitoring in-situ processes, since bioremediation processes involve gaseous components such as oxygen and carbon dioxide. In addition to oxygen and carbon dioxide, contaminant vapors and other trace gaseous components found in the pores of unsaturated soils also provide information on the spatial distribution and the extent of biodegradation. These gaseous components are very mobile, which are ideal analytes for chemical sensors. In this study, oxygen, carbon dioxide, and hydrocarbon subsurface chemical sensors were employed for monitoring in-situ bioremediation of petroleum hydrocarbon contaminated soils.

  1. Chemical fingerprinting of hydrocarbon-contamination in soil.

    PubMed

    Boll, Esther S; Nejrup, Jens; Jensen, Julie K; Christensen, Jan H

    2015-03-01

    Chemical fingerprinting analyses of 29 hydrocarbon-contaminated soils were performed to assess the soil quality and determine the main contaminant sources. The results were compared to an assessment based on concentrations of the 16 priority polycyclic aromatic hydrocarbons pointed out by the U.S. Environmental Protection Agency (EPAPAH16) and total petroleum hydrocarbon (TPH). The chemical fingerprinting strategy proposed in this study included four tiers: (i) qualitative analysis of GC-FID chromatograms, (ii) comparison of the chemical composition of both un-substituted and alkyl-substituted polycyclic aromatic compounds (PACs), (iii) diagnostic ratios of selected PACs, and (iv) multivariate data analysis of sum-normalized PAC concentrations. The assessment criteria included quantitative analysis of 19 PACs and C1-C4 alkyl-substituted homologues of naphthalene, fluorene, dibenzothiophene, phenanthrene, pyrene, and chrysene; and 13 oxygenated polycyclic aromatic compounds (O-PACs). The chemical composition of un-substituted and alkyl-substituted PACs and visual interpretation of GC-FID chromatograms were in combination successful in differentiating pyrogenic and petrogenic hydrocarbon sources and in assessing weathering trends of hydrocarbon contamination in the soils. Multivariate data analysis of sum-normalized concentrations could as a stand-alone tool distinguish between hydrocarbon sources of petrogenic and pyrogenic origin, differentiate within petrogenic sources, and detect weathering trends. Diagnostic ratios of PACs were not successful for source identification of the heavily weathered hydrocarbon sources in the soils. The fingerprinting of contaminated soils revealed an underestimation of PACs in petrogenic contaminated soils when the assessment was based solely on EPAPAH16. As alkyl-substituted PACs are dominant in petrogenic sources, the evaluation of the total load of PACs based on EPAPAH16 was not representative. Likewise, the O-PACs are not represented in soil quality assessments based on EPAPAH16 and TPH. The ?O-PACs ranged between contaminated soils contained considerable amount of O-PACs corresponding to between 6 and 18% of the ?EPAPAH16. PMID:25625139

  2. Chemical hydrogeology in natural and contaminated environments

    USGS Publications Warehouse

    Back, W.; Baedecker, M.J.

    1989-01-01

    Chemical hydrogeology, including organic and inorganic aspects, has contributed to an increased understanding of groundwater flow systems, geologic processes, and stressed environments. Most of the basic principles of inorganic-chemical hydrogeology were first established by investigations of organic-free, regional-scale systems for which simplifying assumptions could be made. The problems of groundwater contamination are causing a shift of emphasis to microscale systems that are dominated by organic-chemical reactions and that are providing an impetus for the study of naturally occurring and manmade organic material. Along with the decrease in scale, physical and chemical heterogeneity become major controls. Current investigations and those selected from the literature demonstrate that heterogeneity increases in importance as the study site decreases from regional-scale to macroscale to microscale. Increased understanding of regional-scale flow systems is demonstrated by selection of investigations of carbonate and volcanic aquifers to show how applications of present-day concepts and techniques can identify controlling chemical reactions and determine their rates; identify groundwater flow paths and determine flow velocity; and determine aquifer characteristics. The role of chemical hydrogeology in understanding geologic processes of macroscale systems is exemplified by selection of investigations in coastal aquifers. Phenomena associated with the mixing zone generated by encroaching sea water include an increase in heterogeneity of permeability, diagenesis of minerals, and formation of geomorphic features, such as caves, lagoons, and bays. Ore deposits of manganese and uranium, along with a simulation model of ore-forming fluids, demonstrate the influence of heterogeneity and of organic compounds on geochemical reactions associated with genesis of mineral deposits. In microscale environments, importance of heterogeneity and consequences of organic reactions in determining the distribution and concentrations cf. constituents are provided by several studies, including infiltration of sewage effluent and migration of creosote in coastal plain aquifers. These studies show that heterogeneity and the dominance of organically controlled reactions greatly increase the complexity of investigations.Current investigations and those selected from the literature demonstrate that heterogeneity increases in importance as the study site decreases from regional-scale to macroscale to microscale. Increased understanding of regional-scale flow systems is demonstrated by selection of investigations of carbonate and volcanic aquifers to show how application of present-day concepts and techniques can identify controlling chemical reactions and determine their rates; identify groundwater flow paths and determine flow velocity; and determine aquifer characteristics. The role of chemical hydrogeology in understanding geologic processes of macroscale systems is exemplified by selection of investigations in coastal aquifers. Ore deposits of manganese and uranium, along with a simulation model of ore-forming fluids, demonstrate the influence of heterogeneity and of organic compounds on geochemical reactions associated with genesis of mineral deposits. In microscale environments, importance of heterogeneity is illustrated by studies of infiltration of sewage effluent and migration of creosote in coastal plain aquifers.

  3. Reviews of environmental contamination and toxicology

    SciTech Connect

    Ware, G.

    2007-07-01

    Review of Environmental Contamination and Toxicology attempts to provide concise, critical reviews of timely advances, philosophy and significant areas of accomplished or needed endeavour in the total field of xenobiotics, in any segment of the environment, as well as toxicological implications. This edition contains a paper 'Health effects of arsenic, fluorine and selenium from indoor burning of Chinese coal, by Liu Guijian, Zheng Liugen, Nurdan S. Duzgoren-Aydin, Gao Lianfen, Liu Junhua, and Peng Zicheng. Other papers are: Chemistry and fate of simazine; Ethanol production: energy, economic, and environmental losses; Arsenic behaviour from groundwater and soil to crops: impacts on agriculture and food safety; Mercury content of hair in different populations relative to fish consumption; and Toxicology of 1,3-butadiene, chloroprene, and isoprene. 15 ills.

  4. Reviews of environmental contamination and toxicology

    SciTech Connect

    Ware, G.W.

    1987-01-01

    These are the first and second volumes under the new Editor of the series that is a continuation of Residue Reviews. The nine reviews in them are as follows: Attenuation of polychlorinated biphenyls in soils; Maleic hydrazide residues in tobacco and their toxicological implications; Fate and persistence of aquatic herbicides; Organophosphorus pesticide residues in fruits and vegetables; Biological half-lives of chemicals in fishes; Propylene chlorohydrins; toxicology, metabolism and environmental fate; The pyrolysis of cannabinoids; Pesticide fate from vine to wine; Transport and transformation of organic chemicals in the soil-air-water ecosystem.

  5. Raman-spectroscopy-based chemical contaminant detection in milk powder

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Addition of edible and inedible chemical contaminants in food powders for purposes of economic benefit has become a recurring trend. In recent years, severe health issues have been reported due to consumption of food powders contaminated with chemical substances. This study examines the effect of sp...

  6. Methods To Characterize Contaminant Residuals After Environmental Dredging

    EPA Science Inventory

    Environmental dredging is a common remedial action for managing contaminated sediments. However, post dredging contaminant concentrations in surface sediment are difficult to predict prior to initiating dredging actions. In some cases, post surface concentrations have been high...

  7. Mapping Environmental Contaminants at Ray Mine, AZ

    NASA Technical Reports Server (NTRS)

    McCubbin, Ian; Lang, Harold

    2000-01-01

    Airborne Visible and InfraRed Imaging Spectrometer (AVIRIS) data was collected over Ray Mine as part of a demonstration project for the Environmental Protection Agency (EPA) through the Advanced Measurement Initiative (AMI). The overall goal of AMI is to accelerate adoption and application of advanced measurement technologies for cost effective environmental monitoring. The site was selected to demonstrate the benefit to EPA in using advanced remote sensing technologies for the detection of environmental contaminants due to the mineral extraction industry. The role of the Jet Propulsion Laboratory in this pilot study is to provide data as well as performing calibration, data analysis, and validation of the AVIRIS results. EPA is also interested in developing protocols that use commercial software to perform such work on other high priority EPA sites. Reflectance retrieval was performed using outputs generated by the MODTRAN radiative transfer model and field spectra collected for the purpose of calibration. We are presenting advanced applications of the ENVI software package using n-Dimensional Partial Unmixing to identify image-derived endmembers that best match target materials reference spectra from multiple spectral libraries. Upon identification of the image endmembers the Mixture Tuned Match Filter algorithm was applied to map the endmembers within each scene. Using this technique it was possible to map four different mineral classes that are associated with mine generated acid waste.

  8. Occurrence and methods of control of chemical contaminants in foods.

    PubMed Central

    Jelinek, C

    1981-01-01

    Contamination of food by chemicals can result from their use on agricultural commodities; accidents or misuse during food handling and processing; nucler weapon testing and operation of nuclear power plants; and disposal of industrial chemicals or by-products with subsequent dispersal into the environment. The Food and Drug Administration (FDA), as the Federal agency mainly responsible for evaluating the hazards of chemical contaminants and enforcing any established tolerance levels for them in foods, has been monitoring pesticides, industrial chemicals, metals, and radionuclides in foods in its nationwide programs for many years. In addition, FDA searches for potential contaminants among the approximately 50,000 industrial chemicals manufactured in the United States and coordinates its efforts with those of other Federal and state agencies in these investigations. The overall results of the FDA surveillance and compliance programs for chemical contaminants in foods, as well as specific examples illustrating the wide range of incidents and types of occurrences, are presented. PMID:6786871

  9. Dermal exposure to environmental contaminants in the Great Lakes.

    PubMed Central

    Moody, R P; Chu, I

    1995-01-01

    This paper reviews the literature to determine the importance of the dermal route of exposure for swimmers and bathers using Great Lakes waters and summarizes the chemical water contaminants of concern in the Great Lakes along with relevant dermal absorption data. We detail in vivo and in vitro methods of quantifying the degree of dermal absorption and discuss a preference for infinite dose data as opposed to finite dose data. The basic mechanisms of the dermal absorption process, routes of chemical entry, and the environmental and physiological factors affecting this process are also reviewed, and we discuss the concepts of surface slick exposure to lipophilic compounds and the adsorption of contaminants to water sediment. After presenting mathematical constructs for calculating the degree of exposure, we present in vitro data concerning skin absorption of polyaromatic hydrocarbons adsorbed to Great Lakes water sediment to show that in a worst-case scenario exposure via the dermal route can be equally important to the oral route. We have concluded that prolonged exposure of the skin, especially under conditions that may enhance dermal absorption (e.g., sunburn) may result in toxicologically significant amounts of certain water contaminants being absorbed. It is recommended that swimming should be confined to public beaches, people should refrain from swimming if they are sunburned, and skin should be washed with soap as soon as possible following exposure. Future studies should be conducted to investigate the importance of the dermal exposure route to swimmers and bathers. PMID:8635434

  10. Environmental impacts on soil and groundwater at airports: origin, contaminants of concern and environmental risks.

    PubMed

    Nunes, L M; Zhu, Y-G; Stigter, T Y; Monteiro, J P; Teixeira, M R

    2011-11-01

    Environmental impacts of airports are similar to those of many industries, though their operations expand over a very large area. Most international impact assessment studies and environmental management programmes have been giving less focus on the impacts to soil and groundwater than desirable. This may be the result of the large attention given to air and noise pollution, relegating other environmental descriptors to a second role, even when the first are comparatively less relevant. One reason that contributes to such "biased" evaluation is the lack of systematic information about impacts to soil and groundwater from airport activities, something the present study intends to help correct. Results presented here include the review of over seven hundred documents and online databases, with the objective of obtaining the following information to support environmental studies: (i) which operations are responsible for chemical releases?; (ii) where are these releases located?; (iii) which contaminants of concern are released?; (iv) what are the associated environmental risks? Results showed that the main impacts occur as a result of fuel storage, stormwater runoff and drainage systems, fuel hydrant systems, fuel transport and refuelling, atmospheric deposition, rescue and fire fighting training areas, winter operations, electrical substations, storage of chemical products by airport owners or tenants, and maintenance of green areas. A new method for ranking environmental risks of organic substances, based on chemical properties, is proposed and applied. Results show that the contaminants with the highest risks are the perfluorochemicals, benzene, trichloroethylene and CCl(4). The obtained information provides a basis for establishing the planning and checking phases of environmental management systems, and may also help in the best design of pollution prevention measures in order to avoid or reduce significant environmental impacts from airports. PMID:22002748

  11. Environmental contamination, product contamination and workers exposure using a robotic system for antineoplastic drug preparation.

    PubMed

    Sessink, Paul J M; Leclercq, Gisle M; Wouters, Dominique-Marie; Halbardier, Loc; Hammad, Chama; Kassoul, Nassima

    2015-04-01

    Environmental contamination, product contamination and technicians exposure were measured following preparation of iv bags with cyclophosphamide using the robotic system CytoCare. Wipe samples were taken inside CytoCare, in the clean room environment, from vials, and prepared iv bags including ports and analysed for contamination with cyclophosphamide. Contamination with cyclophosphamide was also measured in environmental air and on the technicians hands and gloves used for handling the drugs. Exposure of the technicians to cyclophosphamide was measured by analysis of cyclophosphamide in urine. Contamination with cyclophosphamide was mainly observed inside CytoCare, before preparation, after preparation and after daily routine cleaning. Contamination outside CytoCare was incidentally found. All vials with reconstituted cyclophosphamide entering CytoCare were contaminated on the outside but vials with powdered cyclophosphamide were not contaminated on the outside. Contaminated bags entering CytoCare were also contaminated after preparation but non-contaminated bags were not contaminated after preparation. Cyclophosphamide was detected on the ports of all prepared bags. Almost all outer pairs of gloves used for preparation and daily routine cleaning were contaminated with cyclophosphamide. Cyclophosphamide was not found on the inner pairs of gloves and on the hands of the technicians. Cyclophosphamide was not detected in the stationary and personal air samples and in the urine samples of the technicians. CytoCare enables the preparation of cyclophosphamide with low levels of environmental contamination and product contamination and no measurable exposure of the technicians. PMID:24567041

  12. Environmental Mass Spectrometry: Emerging Contaminants and Current Issues (2010 Review)

    EPA Science Inventory

    This biennial review covers developments in environmental mass spectrometry for emerging environmental contaminants over the period of 2008-2009. A few significant references that appeared between January and February 2010 are also included. Analytical Chemistrys current polic...

  13. Environmental Mass Spectrometry: Emerging Contaminants and Current Issues (2010 Review)

    EPA Science Inventory

    This biennial review covers developments in environmental mass spectrometry for emerging environmental contaminants over the period of 2008-2009. A few significant references that appeared between January and February 2010 are also included. Analytical Chemistry’s current polic...

  14. Effects of chemically contaminated sewage sludge on an aphid population

    SciTech Connect

    Culliney, T.W.; Pimentel, D.

    1986-12-01

    Survival and fecundity of green peach aphids, Myzus persicae, were markedly reduced when they were fed on collard plants grown in pots of soil treated with chemically contaminated sewage sludge, as compared to populations on potted plants grown in uncontaminated sludge or on fertilized soil (control). Calculated demographic parameters differed significantly between the contaminated sludge and uncontaminated sludge populations and between the contaminated sludge and control populations. No significant differences were detected between the uncontaminated sludge and control populations. The ecological effects on the aphids suggest that plant uptake and translocation of chemicals from the contaminated sludge affected aphid fitness through direct toxicity and/or reduced nutritional value of the plant. These results indicate that phytophagous insects may be affected by chemical contaminants in sewage sludge used in agriculture.

  15. A framework for net environmental benefit analysis for remediation or restoration of contaminated sites.

    PubMed

    Efroymson, Rebecca A; Nicolette, Joseph P; Suter, Glenn W

    2004-09-01

    Net environmental benefits are gains in value of environmental services or other ecological properties attained by remediation or ecological restoration minus the value of adverse environmental effects caused by those actions. Net environmental benefit analysis (NEBA) is a methodology for comparing and ranking net environmental benefits associated with multiple management alternatives. A NEBA for chemically contaminated sites typically involves comparison of several management alternatives: (1) leaving contamination in place; (2) physically, chemically, or biologically remediating the site through traditional means; (3) improving ecological value through onsite and offsite restoration alternatives that do not directly focus on removal of chemical contamination; or (4) a combination of those alternatives. NEBA involves activities that are common to remedial alternatives analysis for state regulations and the Comprehensive Environmental Response, Compensation, and Liability Act, post-closure and corrective action permits under the Resource Conservation and Recovery Act, evaluation of generic types of response actions pertinent to the Oil Pollution Act, and land management actions that are negotiated with regulatory agencies in flexible regulatory environments (i.e., valuing environmental services or other ecological properties, assessing adverse impacts, and evaluating remediation or restoration options). This article presents a high-level framework for NEBA at contaminated sites with subframeworks for natural attenuation (the contaminated reference state), remediation, and ecological restoration alternatives. Primary information gaps related to NEBA include nonmonetary valuation methods, exposure-response models for all stressors, the temporal dynamics of ecological recovery, and optimal strategies for ecological restoration. PMID:15520889

  16. ENVIRONMENTAL ENGINEERING AND ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    Endocrine disruptors are a class of chemicals of growing interest to the environmental community. USEPA's Risk Assessment Forum defined an endocrine disrupting chemical (EDC) as "an exogenous agent that interferes with the synthesis, secretion, transport, binding, action, or elim...

  17. CHEMICAL CONTAMINANTS IN NONOCCUPATIONALLY EXPOSED U.S. RESIDENTS

    EPA Science Inventory

    The report reviews the manner in which chemical contaminants found in nonoccupationally exposed U.S. residents enter the environment and subsequently human tissue. Approximately 100 contaminants are treated. Sources of literature used in the survey covered a 30-year period, the b...

  18. Characterization of chemical waste site contamination and its extent using bioassays

    SciTech Connect

    Thomas, J.M.; Callahan, C.A.; Cline, J.F.; Greene, J.C.; McShane, M.C.; Miller, W.E.; Peterson, S.A.; Simpson, J.C.; Skalski, J.R.

    1984-12-01

    Bioassays were used in a three-phase research project to assess the comparative sensitivity of test organisms to known chemicals, determine if the chemical components in field soil and water samples containing unknown contaminants could be inferred from our laboratory studies using known chemicals, and to investigate kriging (a relatively new statistical mapping technique) and bioassays as methods to define the areal extent of chemical contamination. The algal assay generally was most sensitive to samples of pure chemicals, soil elutriates and water from eight sites with known chemical contamination. Bioassays of nine samples of unknown chemical composition from the Rocky Mountain Arsenal (RMA) site showed that a lettuce seed soil contact phytoassay was most sensitive. In general, our bioassays can be used to broadly identify toxic components of contaminated soil. Nearly pure compounds of insecticides and herbicides were less toxic in the sensitive bioassays than were the counterpart commercial formulations. This finding indicates that chemical analysis alone may fail to correctly rate the severity of environmental toxicity. Finally, we used the lettuce seed phytoassay and kriging techniques in a field study at RMA to demonstrate the feasibility of mapping contamination to aid in cleanup decisions. 25 references, 9 figures, 9 tables.

  19. Toxicology profiles of chemical and radiological contaminants at Hanford

    SciTech Connect

    Harper, B.L.; Strenge, D.L.; Stenner, R.D.; Maughan, A.D.; Jarvis, M.K.

    1995-07-01

    This document summarizes toxicology information required under Section 3.3 (Toxicity Assessment) of HSRAM, and can also be used to develop the short toxicology profiles required in site assessments (described in HSRAM, Section 3.3.5). Toxicology information is used in the dose-response step of the risk assessment process. The dose-response assessment describes the quantitative relationship between the amount of exposure to a substance and the extent of toxic injury or disease. Data are derived from animal studies or, less frequently, from studies in exposed human populations. The risks of a substance cannot be ascertained with any degree of confidence unless dose-response relations are quantified. This document summarizes dose-response information available from the US Environmental Protection Agency (EPA). The contaminants selected for inclusion in this document represent most of the contaminants found at Hanford (both radiological and chemical), based on sampling and analysis performed during site investigations, and historical information on waste disposal practices at the Hanford Site.

  20. Contamination Effects Due to Space Environmental Interactions

    NASA Technical Reports Server (NTRS)

    Chen, Philip T.; Paquin, Krista C. (Technical Monitor)

    2001-01-01

    Molecular and particulate contaminants are commonly generated from the orbital spacecraft operations that are under the influence of the space environment. Once generated, these contaminants may attach to the surfaces of the spacecraft or may remain in the vicinity of the spacecraft. In the event these contaminants come to rest on the surfaces of the spacecraft or situated in the line-of-sight of the observation path, they will create various degrees of contamination effect which may cause undesirable effects for normal spacecraft operations, There will be circumstances in which the spacecraft may be subjected to special space environment due to operational conditions. Interactions between contaminants and special space environment may alter or greatly increase the contamination effect due to the synergistic effect. This paper will address the various types of contamination generation on orbit, the general effects of the contamination on spacecraft systems, and the typical impacts on the spacecraft operations due to the contamination effect. In addition, this paper will explain the contamination effect induced by the space environment and will discuss the intensified contamination effect resulting from the synergistic effect with the special space environment.

  1. BIOAVAILABILITY OF CHEMICAL CONTAMINANTS IN AQUATIC SYSTEMS

    EPA Science Inventory

    Before a chemical can elicit toxicity, the animal must accumulate a dose at a target tissue of sufficient magnitude to produce a response. Bioavailability refers to the degree to which this accumulation occurs relative to the amount of chemical present in the environment, and is ...

  2. Environmental effects of soil contamination by shale fuel oils.

    PubMed

    Kanarbik, Liina; Blinova, Irina; Sihtme, Mariliis; Knnis-Beres, Kai; Kahru, Anne

    2014-10-01

    Estonia is currently one of the leading producers of shale oils in the world. Increased production, transportation and use of shale oils entail risks of environmental contamination. This paper studies the behaviour of two shale fuel oils (SFOs)--'VKG D' and 'VKG sweet'--in different soil matrices under natural climatic conditions. Dynamics of SFOs' hydrocarbons (C10-C40), 16 PAHs, and a number of soil heterotrophic bacteria in oil-spiked soils was investigated during the long-term (1 year) outdoor experiment. In parallel, toxicity of aqueous leachates of oil-spiked soils to aquatic organisms (crustaceans Daphnia magna and Thamnocephalus platyurus and marine bacteria Vibrio fischeri) and terrestrial plants (Sinapis alba and Hordeum vulgare) was evaluated. Our data showed that in temperate climate conditions, the degradation of SFOs in the oil-contaminated soils was very slow: after 1 year of treatment, the decrease of total hydrocarbons' content in the soil did not exceed 25 %. In spite of the comparable chemical composition of the two studied SFOs, the VKG sweet posed higher hazard to the environment than the heavier fraction (VKG D) due to its higher mobility in the soil as well as higher toxicity to aquatic and terrestrial species. Our study demonstrated that the correlation between chemical parameters (such as total hydrocarbons or total PAHs) widely used for the evaluation of the soil pollution levels and corresponding toxicity to aquatic and terrestrial organisms was weak. PMID:24865504

  3. WORKSHOP ON ENVIRONMENTALLY CONSCIOUS CHEMICAL PROCESS DESIGN

    EPA Science Inventory

    To encourage the consideration of environmental issues during chemical process design, the USEPA has developed techniques and software tools to evaluate the relative environmental impact of a chemical process. These techniques and tools aid in the risk management process by focus...

  4. Chemical contaminants in the Wadden Sea: Sources, transport, fate and effects

    NASA Astrophysics Data System (ADS)

    Laane, R. W. P. M.; Vethaak, A. D.; Gandrass, J.; Vorkamp, K.; Khler, A.; Larsen, M. M.; Strand, J.

    2013-09-01

    The Wadden Sea receives contaminants from various sources and via various transport routes. The contaminants described in this overview are various metals (Cd, Cu, Hg, Pb and Zn) and various organic contaminants (polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and lindane (hexachlorocyclohexane, ?-HCH)). In addition, information is presented about other and emerging contaminants such as antifouling biocides (e.g. TBT and Irgarol), brominated flame retardants (BFRs), poly- and perfluorinated compounds (PFCs) and pharmaceutical and personal care products (PPCPs). Special attention is given to biogeochemical processes that contribute to the mobilization of contaminants in the surface sediments of the Wadden Sea. Finally, the effects on organisms of contaminants are reviewed and discussed. The main source of contaminants in the Wadden Sea are the rivers Rhine (via de Dutch coastal zone), Elbe and Weser. The Wadden Sea is not a sink for contaminants and adsorbed contaminants are transported from east to west. The surface sediments of the Wadden Sea are an important source for contaminants to the water above. The input and concentration of most contaminants have significantly decreased in water, sediments, organisms (e.g., mussel, flounder and bird eggs) in various parts of the Wadden Sea in the last three decades. Remarkably, the Cd concentration in mussels is increasing the last decades. In recent decades, the effects of contaminants on organisms (e.g., flounder, seal) have fallen markedly. Most of the affected populations have recovered, except for TBT induced effects in snails. Little is known about the concentration and effects of most emerging contaminants and the complex environmental mixtures of contaminants. It is recommended to install an international coordinated monitoring programme for contaminants and their effects in the whole Wadden Sea and to identify the chemical contaminants that really cause the effect.

  5. PILOT-SCALE INCINERATION OF CONTAMINATED SOILS FROM THE DRAKE CHEMICAL SUPERFUND SITE

    EPA Science Inventory

    A series of pilot-scale incineration tests were performed at the U.S. Environmental Protection Agency's (EPA's) Incineration Research Facility to evaluate the potential of incineration as an option to treat contaminated soils from the Drake Chemical Superfund site in Lock Haven, ...

  6. RELEASE OF CHEMICALS FROM CONTAMINATED SOILS. (R822721C529)

    EPA Science Inventory

    At sites that contain contaminated soils, there can be questions about the magnitude of risk posed by the chemicals in the soils and about the cleanup levels that should be achieved. Knowledge about the rate of release of chemicals is important to answers to such questions. Th...

  7. Environmental contamination by mercury in Iraq

    PubMed Central

    Jernelv, A.

    1976-01-01

    Following the outbreak of organomercury poisoning in Iraq, an investigation was carried out during the spring and summer of 1972 to evaluate environmental contamination by organomercury. Analyses were performed on fish of several species (not typical predators) and on a few specimens of aquatic birds (not fish-eating). Most fish samples contained concentrations in muscle ranging from 0.01 to 0.15 mg/kg. These concentrations are within the range found in tropical rivers. Higher figures, 0.3-0.5 mg/kg, were found downstream from a caustic soda plant south of Baghdad. A few cases of very high mercury concentrations (25-30 mg/kg) were reported from an area where fish kills had occurred. Aquatic birds (ducks and waders) contained low concentrations of mercury (900-2750 ng/g). Tail feathers of seed-eating birds were found to contain 13 500-21 000 ng/g of mercury, which is about 10 times higher than values reported from Ethiopia and within the range found in Sweden and Canada. Insect-eating birds contained 1850-5200 ng/g, which is thought to be slightly elevated. Extremely high concentrations of mercury were found in muscle tissue of dead seed-eating birds (15 000-40 000 ng/g), while feathers contained similar concentrations (9000-52 000 ng/g). These extremely high concentrations were found only in the vicinity of storehouses where treated seed was kept. No birds of prey could be caught and analysed. PMID:1086159

  8. Microbial contamination and chemical toxicity of the Rio Grande

    PubMed Central

    Mendoza, Jose; Botsford, James; Hernandez, Jose; Montoya, Anna; Saenz, Roswitha; Valles, Adrian; Vazquez, Alejandro; Alvarez, Maria

    2004-01-01

    Background The Rio Grande River is the natural boundary between U.S. and Mexico from El Paso, TX to Brownsville, TX. and is one of the major water resources of the area. Agriculture, farming, maquiladora industry, domestic activities, as well as differences in disposal regulations and enforcement increase the contamination potential of water supplies along the border region. Therefore, continuous and accurate assessment of the quality of water supplies is of paramount importance. The objectives of this study were to monitor water quality of the Rio Grande and to determine if any correlations exist between fecal coliforms, E. coli, chemical toxicity as determined by Botsford's assay, H. pylori presence, and environmental parameters. Seven sites along a 112-Km segment of the Rio Grande from Sunland Park, NM to Fort Hancock, TX were sampled on a monthly basis between January 2000 and December 2002. Results The results showed great variability in the number of fecal coliforms, and E. coli on a month-to-month basis. Fecal coliforms ranged between 0–106 CFU/100 ml while E. coli ranged between 6 to > 2419 MPN. H. pylori showed positive detection for all the sites at different times. Toxicity ranged between 0 to 94% of inhibition capacity (IC). Since values above 50% are considered to be toxic, most of the sites displayed significant chemical toxicity at different times of the year. No significant correlations were observed between microbial indicators and chemical toxicity. Conclusion The results of the present study indicate that the 112-Km segment of the Rio Grande river from Sunland Park, NM to Fort Hancock, TX exceeds the standards for contact recreation water on a continuous basis. In addition, the presence of chemical toxicity in most sites along the 112-Km segment indicates that water quality is an area of concern for the bi-national region. The presence of H. pylori adds to the potential health hazards of the Rio Grande. Since no significant correlation was observed between the presence of H. pylori antigens and the two indicators of fecal contamination, we can conclude that fecal indicators cannot be used to detect the presence of H. pylori reliably in surface water. PMID:15104800

  9. Chemical contaminants in swimming pools: Occurrence, implications and control.

    PubMed

    Teo, Tiffany L L; Coleman, Heather M; Khan, Stuart J

    2015-03-01

    A range of trace chemical contaminants have been reported to occur in swimming pools. Current disinfection practices and monitoring of swimming pool water quality are aimed at preventing the spread of microbial infections and diseases. However, disinfection by-products (DBPs) are formed when the disinfectants used react with organic and inorganic matter in the pool. Additional chemicals may be present in swimming pools originating from anthropogenic sources (bodily excretions, lotions, cosmetics, etc.) or from the source water used where trace chemicals may already be present. DBPs have been the most widely investigated trace chemical contaminants, including trihalomethanes (THMs), haloacetic acids (HAAs), halobenzoquinones (HBQs), haloacetonitriles (HANs), halonitromethanes (HNMs), N-nitrosamines, nitrite, nitrates and chloramines. The presence and concentrations of these chemical contaminants are dependent upon several factors including the types of pools, types of disinfectants used, disinfectant dosages, bather loads, temperature and pH of swimming pool waters. Chemical constituents of personal care products (PCPs) such as parabens and ultraviolet (UV) filters from sunscreens have also been reported. By-products from reactions of these chemicals with disinfectants and UV irradiation have been reported and some may be more toxic than their parent compounds. There is evidence to suggest that exposure to some of these chemicals may lead to health risks. This paper provides a detailed review of various chemical contaminants reported in swimming pools. The concentrations of chemicals present in swimming pools may also provide an alternative indicator to swimming pool water quality, providing insights to contamination sources. Alternative treatment methods such as activated carbon filtration and advanced oxidation processes may be beneficial in improving swimming pool water quality. PMID:25497109

  10. Lethal Dietary Toxicities of Environmental Contaminants and Pesticides to Coturnix

    USGS Publications Warehouse

    Hill, E.F.; Camardese, M.B.

    1986-01-01

    Five-day subacute dietary toxicity tests of 193 potential environmental contaminants, pesticides, organic solvents, and various adjuvants are presented for young coturnix (Japanese quail, Coturnix japonica Temminck and Schlegel). The report provides the most comprehensive data base available for avian subacute dietary toxicity tests and is primarily intended for use in ranking toxicities by a standard method that has a reasonable degree of environmental relevance. Findings are presented in two parts: Part I is a critique of selected drugs that includes discussion of subacute toxicity in relation to chemical class and structure, pesticide formulation, and age of animals; Part II is a summary of toxicologic findings for each test substance and provides a statistically basis for comparing toxicities. Data presented include the median lethal concentration (LC50), slope of the probit regression curve (dose-response curve), response chronology, and food consumption. We observed that: 1) fewer than 15% of the compounds were classed 'very' or 'highly' toxic (i.e, LC50 < 200 ppm) and all of these were either chlorinated hydrocarbons, organophosphates, or organometallics; 2) subacute toxicity may vary widely among structurally similar chemicals and between different formulations of the same chemical; therefore, conclusions about lethal hazard must be made cautiously until the actual formulation of inset has been tested: 3) inclusion of a general standard in each battery of tests is useful for detection of atypical trials and monitoring population changes but should not be used indiscriminantly for adjusting LC50's for intertest differences unless the chemicals of concern and the standard elicit their toxicities through the same action; 4) although other species have been tested effectively under the subacute protocol, coturnix were ideal for the stated purpose of this research because they are inexpensive, well-adapted to the laboratory environment, and yield good intertest reproducibility of response.

  11. THYROID DISRUPTING CHEMICALS: CHALLENGES IN ASSESSING NEUROTOXIC RISK FROM ENVIRONMENTAL MIXTURES.

    EPA Science Inventory

    Environmental contaminants are known to act as thyroid disrupting chemicals (TDCs). Broadly defined, TDCs are xenobiotics that alter the structure or function of the thyroid gland, alter regulatory enzymes associated with thyroid hormone (TH) homeostasis, or change circulating o...

  12. Optimal Exposure Biomarkers for Nonpersistent Chemicals in Environmental Epidemiology

    PubMed Central

    Calafat, Antonia M.; Longnecker, Matthew P.; Koch, Holger M.; Swan, Shanna H.; Hauser, Russ; Goldman, Lynn R.; Lanphear, Bruce P.; Rudel, Ruthann A.; Engel, Stephanie M.; Teitelbaum, Susan L.; Whyatt, Robin M.

    2015-01-01

    Summary We discuss considerations that are essential when evaluating exposure to nonpersistent, semivolatile environmental chemicals such as phthalates and phenols (e.g., bisphenol A). A biomarker should be chosen to best represent usual personal exposures and not recent, adventitious, or extraneous exposures. Biomarkers should be selected to minimize contamination arising from collection, sampling, or analysis procedures. Pharmacokinetics should be considered; for example, nonpersistent, semivolatile chemicals are metabolized quickly, and urine is the compartment with the highest concentrations of metabolites. Because these chemicals are nonpersistent, knowledge of intraindividual reliability over the biologic window of interest is also required. In recent years researchers have increasingly used blood as a matrix for characterizing exposure to nonpersistent chemicals. However, the biologic and technical factors noted above strongly support urine as the optimal matrix for measuring nonpersistent, semivolatile, hydrophilic environmental agents. PMID:26132373

  13. Assimilation efficiencies of chemical contaminants in aquatic invertebrates: A synthesis

    SciTech Connect

    Wang, W.X.; Fisher, N.S.

    1999-09-01

    Assimilation efficiencies of contaminants from ingested food are critical for understanding chemical accumulation and trophic transfer in aquatic invertebrates. Assimilation efficiency is a first-order physiological parameter that can be used to systematically compare the bioavailability of different contaminants from different foods. The various techniques used to measure contaminant assimilation efficiencies are reviewed. Pulse-chase feeding techniques and the application of gamma-emitting radiotracers have been invaluable in measuring metal assimilation efficiencies in aquatic animals. Uniform radiolabeling of food is required to measure assimilation, but this can be difficult when sediments are the food source. Biological factors that influence contaminant assimilation include food quantity and quality, partitioning of contaminants in the food particles, and digestive physiology of the animals. Other factors influencing assimilation include the behavior of the chemical within the animal's gut and its associations with different geochemical fractions of food particles. Assimilation efficiency is a critical parameter to determine (and to make predictions of) bioaccumulation of chemicals from dietary exposure. Robust estimates of assimilation efficiency coupled with estimates of aqueous uptake can be used to determine the relative importance of aqueous and dietary exposures. For bioaccumulation of metals from sediments, additional studies are required to test whether metals bound to the acid-volatile sulfide fraction of sediments can be available to benthic deposit-feeding inverterbrates. Most assimilation efficiency studies have focused on chemical transfer in organisms at the bottom of the food chain; additional studies are required to examine chemical transfer at higher trophic levels.

  14. The stingless bee species, Scaptotrigona aff. depilis, as a potential indicator of environmental pesticide contamination.

    PubMed

    de Souza Rosa, Annelise; I'Anson Price, Robbie; Ferreira Caliman, Maria Juliana; Pereira Queiroz, Elisa; Blochtein, Betina; Slvia Soares Pires, Carmen; Imperatriz-Fonseca, Vera Lucia

    2015-08-01

    Neonicotinoids have the potential to enter the diet of pollinators that collect resources from contaminated plants. The species Scaptotrigona aff. depilis (Moure, 1942) can be a useful indicator of the prevalence of these chemicals in the environment. Using high-performance liquid chromatography-mass spectrometry, the authors devised a protocol for neonicotinoid residue extraction and detected the presence of neonicotinoids in the bee bodies. Thus, the authors consider this species to be a potential indicator of environmental contamination. PMID:26190578

  15. Environmental simulation testing of solar cell contamination by hydrazine

    NASA Technical Reports Server (NTRS)

    Moore, W. W., Jr.

    1972-01-01

    Test results for thermal vacuum and radiation environment simulation of hydrazine contamination are discussed. Solar cell performance degradation, measured by short circuit current, is presented in correlation with the variations used in environmental parameters.

  16. High Throughput Screening For Hazard and Risk of Environmental Contaminants

    EPA Science Inventory

    High throughput toxicity testing provides detailed mechanistic information on the concentration response of environmental contaminants in numerous potential toxicity pathways. High throughput screening (HTS) has several key advantages: (1) expense orders of magnitude less than an...

  17. Project Overview: PERCHLORATE ENVIRONMENTAL CONTAMINATION - TOXICOLOGICAL REVIEW AND RISK CHARACTERIZATION

    EPA Science Inventory

    The human health and ecological assessment issues related to environmental contamination by perchlorate are complex and continue to emerge. Perchlorate, ClO4-, is an anion that originates as a contaminant from the solid salts of ammonium, potassium or sodium perchlorate. These ...

  18. Petroleum contaminated soils - Remediation techniques, environmental fate and risk assessment

    SciTech Connect

    Kostecki, P.T.; Calabrese, E.J.

    1988-01-01

    This book contains information about rational and scientifically defensible solutions to today's problems caused by petroleum contaminated soils. This book delivers state-of-the-art information on both technical and regulatory issues such as environmental fate, health effects, risk assessment and remedial alternatives. It shows why petroleum contaminated soils are a problem - and proposes solutions for that problem.

  19. Bacteria and Emerging Chemical Contaminants in the St. Clair River/Lake St. Clair Basin, Michigan

    USGS Publications Warehouse

    Fogarty, Lisa R.

    2007-01-01

    Introduction Since the enactment of the Clean Water Act in 1972, awareness of the quality of the Nation's water has continued to improve. Despite improvements to wastewater-treatment systems and increased regulation on waste discharge, bacterial and chemical contamination is still a problem for many rivers and lakes throughout the United States. Pathogenic microorganism and newly recognized chemical contaminants have been found in waters that are used for drinking water and recreation (Rose and Grimes, 2001; Kolpin and others, 2002). This summary of bacteria and emerging-chemical-contaminant monitoring in the St. Clair River/Lake St. Clair Basin (fig. 1) was initiated by the Lake St. Clair Regional Monitoring Project (LSCRMP) in 2003, in cooperation with the Michigan Department of Environmental Quality (MDEQ), the Counties of Macomb, Oakland, St. Clair, and Wayne, and the U.S. Geological Survey (USGS).

  20. Emerging Environmental Contaminants: What’s New

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise (including potential adverse health effects, bioaccumulation, and widespread distribution). This presentation will discuss emerging environmental c...

  1. Emerging Environmental Contaminants: Whats New

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise (including potential adverse health effects, bioaccumulation, and widespread distribution). This presentation will discuss emerging environmental c...

  2. Chemical tailoring of steam to remediate underground mixed waste contaminents

    DOEpatents

    Aines, Roger D. (Livermore, CA); Udell, Kent S. (Berkeley, CA); Bruton, Carol J. (Livermore, CA); Carrigan, Charles R. (Tracy, CA)

    1999-01-01

    A method to simultaneously remediate mixed-waste underground contamination, such as organic liquids, metals, and radionuclides involves chemical tailoring of steam for underground injection. Gases or chemicals are injected into a high pressure steam flow being injected via one or more injection wells to contaminated soil located beyond a depth where excavation is possible. The injection of the steam with gases or chemicals mobilizes contaminants, such as metals and organics, as the steam pushes the waste through the ground toward an extraction well having subatmospheric pressure (vacuum). The steam and mobilized contaminants are drawn in a substantially horizontal direction to the extraction well and withdrawn to a treatment point above ground. The heat and boiling action of the front of the steam flow enhance the mobilizing effects of the chemical or gas additives. The method may also be utilized for immobilization of metals by using an additive in the steam which causes precipitation of the metals into clusters large enough to limit their future migration, while removing any organic contaminants.

  3. Tactical approach to maneuvering within the chemical contamination labyrinth

    SciTech Connect

    Joseph, T.W.

    1990-12-31

    The Department of Energy (DOE) recognized the need and accepts the responsibility for understanding the reality and mitigating the consequence of the complex chemical contamination legacy it inherited as well as controlling, reducing, and eliminating extant emissions and effluents. The key to maneuvering through this complicated and multifaceted labyrinth of concerns, from which a meaningful, high quality, and cost-effective restoration/mitigation machine is then set in motions, is the ability to perform accurate, factual, and explicit health and environmental/ecological risk assessments. Likewise, the common denominator for carrying out this essential task is to have access to comprehensive and reliable data of known quality with which to perform those analyses. DOE is committed to identifying the data universe; to technically scrutinize and ensure the quality of that data; to develop efficient and cost-effective means to maximize the handling, utilization, and sharing of that universe; and to undertake those assessments. DOE views this as an effort that can only be accomplished through a merging of the technical excellence that exists within federal and state agencies, academia, and industry. The task at hand is so large that only by integrating that intelligence base can we hope to accomplish the goals of establishing meaningful standards, developing functional and effective solutions, and providing quality guidance at a national scale.

  4. DESIGNING ENVIRONMENTALLY FRIENDLY CHEMICAL PROCESSES

    EPA Science Inventory

    The design of a chemical process involves many aspects: from profitability, flexibility and reliability to safety to the environment. While each of these is important, in this work, the focus will be on profitability and the environment. Key to the study of these aspects is the ...

  5. Toxicokinetic Triage for Environmental Chemicals

    EPA Science Inventory

    Toxicokinetic (TK) models are essential for linking administered doses to blood and tissue concentrations. In vitro-to-in vivo extrapolation (IVIVE) methods have been developed to determine TK from limited in vitro measurements and chemical structure-based property predictions, p...

  6. Chemical Health Effects Assessment Methodology for airborne contaminants

    SciTech Connect

    Brown, H.S.; West, C.R.; Bishop, D.R.

    1987-09-01

    Chemical Health Effects Assessment Methodology (CHEM) is a new procedure for assessing hazardous properties of airborne toxic contaminants. CHEM evaluates substances for four major health effect categories: carcinogenicity, mutagenicity, reproductive/developmental toxicity, and toxic effects other than the first three. Three elements are considered in the assessment: weight of evidence, potency, and severity of effect. This approach produces a profile of toxic properties of chemicals which preserves their unique multidimensional character and highlights data gaps.

  7. Chemical speciation of uranium in contaminated and chemically remediated soils by micro X-ray absorption spectroscopy

    SciTech Connect

    Bertsch, P.M.; Hunter, D.B.

    1995-12-31

    Spatially resolved XAS and X-ray fluorescence spectroscopic studies were conducted to investigate the distribution and chemical speciation of uranium (U) in contaminated soils and sediments prior to and following chemical extraction. This approach provided direct information on the chemical speciation of uranium in micro-regions of contaminated soils and sediments sampled at the Fernald Environmental Management Project Site and the Savannah River Site. Using X-ray absorption near edge structure (XANES) spectroscopy, the predominant oxidation state of uranium in the contaminated sediments was determined. A calibration method was developed which enhanced the ability to collect oxidation state information at much lower concentrations in a reasonable time frame and allowed for the generation of oxidation state distribution maps at a 20 {mu}m spatial resolution. Additional experiments conducted on mixed uranium containing mineral phases confirmed the ability of the method to accurately delineate proportions of uranium in different oxidation states. Furthermore, a method of imbedding particles in a nonreactive silicon polymer was developed such that individual particles could be examined before and after extraction with a wide range of chemicals used in sequential extraction techniques and others proposed for chemical intervention technologies. Studies revealed that the sodium carbonate treatment proposed to extract U from soils efficiently removed U(VI), except when present as a phosphate phase, and was inefficient at extracting U(IV) phases. The results of these studies demonstrated the utility of spatially resolved XAS methods for in situ chemical speciation of U and other metals and metalloids.

  8. Environmental Chemicals and Nervous System Dysfunction 1

    PubMed Central

    Damstra, Terri

    1978-01-01

    Selected examples of associations between nervous system diseases and exposures to occupational and environmental chemicals have been reviewed. Recent outbreaks of human neurotoxicity from both wellknown and previously unknown toxicants reemphasize the need for the medical community to give increased attention to chemical causes of nervous system dysfunction. PMID:87062

  9. HUMAN HEALTH IMPACT OF ENVIRONMENTAL ESTROGENIC CHEMICALS

    EPA Science Inventory

    HUMAN HEALTH IMPACT OF ENVIRONMENTAL ESTROGENIC CHEMICALS.

    Robert J. Kavlock, Reproductive Toxicology Division, NHEERL, ORD, US Environmental Protection Agency, Research Triangle Park, NC USA.

    Over the past several decades a hypothesis has been put forth that a numb...

  10. Environmental Mass Spectrometry: Emerging Contaminants and Current Issues 2012

    EPA Science Inventory

    This biennial Review covers developments in environmental mass spectrometry for emerging environmental contaminants over the period of 20102011. Analytical Chemistrys policy is to limit reviews to a maximum of 250 significant references and to mainly focus on new trends. Ev...

  11. EMERGING ENVIRONMENTAL CONTAMINANTS: ACHIEVEMENTS AND CHALLENGES WITH MASS SPECTROMETRY

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise. This presentation will discuss emerging contaminants that the U.S. Environmental Protection Agency (EPA) and other agencies are currently concerned...

  12. Environmental chemical exposures and human epigenetics

    PubMed Central

    Hou, Lifang; Zhang, Xiao; Wang, Dong; Baccarelli, Andrea

    2012-01-01

    Every year more than 13 million deaths worldwide are due to environmental pollutants, and approximately 24% of diseases are caused by environmental exposures that might be averted through preventive measures. Rapidly growing evidence has linked environmental pollutants with epigenetic variations, including changes in DNA methylation, histone modifications and microRNAs. Environ mental chemicals and epigenetic changes All of these mechanisms are likely to play important roles in disease aetiology, and their modifications due to environmental pollutants might provide further understanding of disease aetiology, as well as biomarkers reflecting exposures to environmental pollutants and/or predicting the risk of future disease. We summarize the findings on epigenetic alterations related to environmental chemical exposures, and propose mechanisms of action by means of which the exposures may cause such epigenetic changes. We discuss opportunities, challenges and future directions for future epidemiology research in environmental epigenomics. Future investigations are needed to solve methodological and practical challenges, including uncertainties about stability over time of epigenomic changes induced by the environment, tissue specificity of epigenetic alterations, validation of laboratory methods, and adaptation of bioinformatic and biostatistical methods to high-throughput epigenomics. In addition, there are numerous reports of epigenetic modifications arising following exposure to environmental toxicants, but most have not been directly linked to disease endpoints. To complete our discussion, we also briefly summarize the diseases that have been linked to environmental chemicals-related epigenetic changes. PMID:22253299

  13. USE OF APATITE FOR CHEMICAL STABILIZATION OF SUBSURFACE CONTAMINANTS

    SciTech Connect

    Dr. William D. Bostick

    2003-05-01

    Groundwater at many Federal and civilian industrial sites is often contaminated with toxic metals at levels that present a potential concern to regulatory agencies. The U.S. Department of Energy (DOE) has some unique problems associated with radionuclides (primarily uranium), but metal contaminants most likely drive risk-based cleanup decisions, from the perspective of human health, in groundwater at DOE and U.S. Environmental Protection Agency (EPA) Superfund Sites include lead (Pb), arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), zinc (Zn), selenium (Se), antimony (Sb), copper (Cu) and nickel (Ni). Thus, the regulatory ''drivers'' for toxic metals in contaminated soils/groundwaters are very comparable for Federal and civilian industrial sites, and most sites have more than one metal above regulatory action limits. Thus improving the performance of remedial technologies for metal-contaminated groundwater will have ''dual use'' (Federal and civilian) benefit.

  14. Environmental chemicals and microRNAs

    PubMed Central

    Hou, Lifang; Wang, Dong; Baccarelli, Andrea

    2013-01-01

    MicroRNAs (miRNAs) are short single-stranded non-coding molecules that function as negative regulators to silence or suppress gene expression. Aberrant miRNA expression has been implicated in a several cellular processes and pathogenic pathways of a number of diseases. Evidence is rapidly growing that miRNA regulation of gene expression may be affected by environmental chemicals. These environmental exposures include those that have frequently been associated with chronic diseases, such as heavy metals, air pollution, bisphenol A, and cigarette smoking. In this article, we review the published data on miRNAs in relation to the exposure to several environmental chemicals, and discuss the potential mechanisms that may link environmental chemicals to miRNA alterations. We further discuss the challenges in environmental-miRNA research and possible future directions. The cumulating evidence linking miRNAs to environmental chemicals, coupled with the unique regulatory role of miRNAs in gene expression, makes miRNAs potential biomarkers for better understanding the mechanisms of environmental diseases. PMID:21609724

  15. Predicting biological effects of environmental mixtures using exposure:activity ratios (EAR) derived from US EPA’s ToxCast data: Retrospective application to chemical monitoring data

    EPA Science Inventory

    Chemical monitoring has been widely used in environmental surveillance to assess exposure to environmental contaminants which could represent potential hazards to exposed organisms. However, the ability to detect chemicals in the environment has rapidly outpaced assessment of pot...

  16. Predicting biological effects of environmental mixtures using exposure:activity ratios (EAR) derived from US EPAs ToxCast data: Retrospective application to chemical monitoring data

    EPA Science Inventory

    Chemical monitoring has been widely used in environmental surveillance to assess exposure to environmental contaminants which could represent potential hazards to exposed organisms. However, the ability to detect chemicals in the environment has rapidly outpaced assessment of pot...

  17. Application, chemistry, and environmental implications of contaminant-immobilization amendments on agricultural soil and water quality.

    TOXLINE Toxicology Bibliographic Information

    Udeigwe TK; Eze PN; Teboh JM; Stietiya MH

    2011-01-01

    Contaminants such as nitrogen (N), phosphorus (P), dissolved organic carbon (DOC), arsenic (As), heavy metals, and infectious pathogens are often associated with agricultural systems. Various soil and water remediation techniques including the use of chemical amendments have been employed to reduce the risks associated with these contaminants. This paper reviews the use of chemical amendments for immobilizing principal agricultural contaminants, the chemistry of contaminant immobilization, and the environmental consequences associated with the use of these chemical products. The commonly used chemical amendments were grouped into aluminum-, calcium-, and iron-containing products. Other products of interest include phosphorus-containing compounds and silicate clays. Mechanisms of contaminant immobilization could include one or a combination of the following: surface precipitation, adsorption to mineral surfaces (ion exchange and formation of stable complexes), precipitation as salts, and co-precipitation. The reaction pH, redox potential, clay minerals, and organic matter are potential factors that could control contaminant-immobilization processes. Reviews of potential environmental implications revealed that undesirable substances such as trace elements, fluoride, sulfate, total dissolved solids, as well as radioactive materials associated with some industrial wastes used as amendment could be leached to ground water or lost through runoff to receiving water bodies. The acidity or alkalinity associated with some of the industrial-waste amendments could also constitute a substantial environmental hazard. Chemical amendments could introduce elements capable of inducing or affecting the activities of certain lithotrophic microbes that could influence vital geochemical processes such as mineral dissolution and formation, weathering, and organic matter mineralization.

  18. Chemical contaminants on DOE lands and selection of contaminant mixtures for subsurface science research

    SciTech Connect

    Riley, R.G.; Zachara, J.M. )

    1992-04-01

    This report identifies individual contaminants and contaminant mixtures that have been measured in the ground at 91 waste sites at 18 US Department of Energy (DOE) facilities within the weapons complex. The inventory of chemicals and mixtures was used to identify generic chemical mixtures to be used by DOE's Subsurface Science Program in basic research on the subsurface geochemical and microbiological behavior of mixed contaminants (DOE 1990a and b). The generic mixtures contain specific radionuclides, metals, organic ligands, organic solvents, fuel hydrocarbons, and polychlorinated biphenyls (PCBs) in various binary and ternary combinations. The mixtures are representative of in-ground contaminant associations at DOE facilities that are likely to exhibit complex geochemical behavior as a result of intercontaminant reactions and/or microbiologic activity stimulated by organic substances. Use of the generic mixtures will focus research on important mixed contaminants that are likely to be long-term problems at DOE sites and that will require cleanup or remediation. The report provides information on the frequency of associations among different chemicals and compound classes at DOE waste sites that require remediation.

  19. Chemical contaminants on DOE lands and selection of contaminant mixtures for subsurface science research

    SciTech Connect

    Riley, R.G.; Zachara, J.M.

    1992-04-01

    This report identifies individual contaminants and contaminant mixtures that have been measured in the ground at 91 waste sites at 18 US Department of Energy (DOE) facilities within the weapons complex. The inventory of chemicals and mixtures was used to identify generic chemical mixtures to be used by DOE`s Subsurface Science Program in basic research on the subsurface geochemical and microbiological behavior of mixed contaminants (DOE 1990a and b). The generic mixtures contain specific radionuclides, metals, organic ligands, organic solvents, fuel hydrocarbons, and polychlorinated biphenyls (PCBs) in various binary and ternary combinations. The mixtures are representative of in-ground contaminant associations at DOE facilities that are likely to exhibit complex geochemical behavior as a result of intercontaminant reactions and/or microbiologic activity stimulated by organic substances. Use of the generic mixtures will focus research on important mixed contaminants that are likely to be long-term problems at DOE sites and that will require cleanup or remediation. The report provides information on the frequency of associations among different chemicals and compound classes at DOE waste sites that require remediation.

  20. Long Island Sound: Distributions, trends, and effects of chemical contamination

    SciTech Connect

    Turgeon, D.D.; O'Connor, T.P. )

    1991-09-01

    Trace metals and organic contaminants concentrations are monitored annually in surface sediments, blue mussel tissue, and winter flounder livers at multiple sites in Long Island Sound by National Oceanic and Atmospheric Administration's National Status and Trends (NS and T) program for Marine Environmental Quality. The NS and T program is also conducting various studies on the bioeffects of contaminants in the sound. Three years of monitoring results indicate organic and elemental contaminants concentrations in sediments and biota at sites in the western portion of the sound are high on a national scale. Possible decreasing trends in cadmium and chlordane in the second are suggested by the 1986-1988 data for their concentrations in mussels. A comparison between NS and T Mussel Watch results and those of the Environmental Protection Agency's Mussel Watch, conducted from 1976 through 1978, indicated a decadal increase in copper concentrations and a decrease in lead in the sound. Bioeffects studies in the sound have revealed responses in contamination only in localized zones where contaminant levels are very high.

  1. Environmental contaminants in bald eagle eggs

    USGS Publications Warehouse

    Wiemeyer, Stanley N.; Bunck, C.M.; Stafford, C.J.

    1991-01-01

    Bald Eagle eggs (1968-84) were analyzed for organochlorine pesticides, PCBs and mercury. DDE declined in WI, ME and the Chesapeake Bay. DDE was most closely related to shell thickness and reproduction at sampled breeding areas. Sixteen ppm DDE (wet weight) was associated with 15% shell thinning. Reproduction was normal when eggs at sampled breeding areas contained <3.6 ppm DDE; success was nearly halved between 3.6 and 6.3 ppm and halved again when concentrations exceeded 6.3 ppm. Other contaminants were associated with poor reproduction and eggshell thinning; however, their impact appeared secondary to that of DDE.

  2. HISTORY OF MERCURY USE AND ENVIRONMENTAL CONTAMINATION

    SciTech Connect

    Brooks, Scott C; Southworth, George R

    2011-01-01

    Between 1950 and 1963 approximately 11 million kilograms of mercury (Hg) were used at the Oak Ridge Y-12 National Security Complex (Y-12 NSC) for lithium isotope separation processes. About 3% of the Hg was lost to the air, soil and rock under facilities, and East Fork Poplar Creek (EFPC) which originates in the plant site. Smaller amounts of Hg were used at other Oak Ridge facilities with similar results. Although the primary Hg discharges from Y-12 NSC stopped in 1963, small amounts of Hg continue to be released into the creek from point sources and diffuse contaminated soil and groundwater sources within Y-12 NSC. Mercury concentration in EFPC has decreased 85% from not, vert, similar2000 ng/L in the 1980s. In general, methylmercury concentrations in water and in fish have not declined in response to improvements in water quality and exhibit trends of increasing concentration in some cases.Mercury discharges from an industrial plant have created a legacy contamination problem exhibiting complex and at times counter-intuitive patterns in Hg cycling.

  3. Environmental contaminants in breast milk from the central Asian republics.

    PubMed

    Lederman, S A

    1996-01-01

    Concern has been widespread about possible high levels of environmental contamination in areas of the former Soviet Union. Some of this concern has focussed on toxicants in human milk and their potential adverse effects on the breastfeeding child, but published data have been virtually unavailable. This study collected previously unpublished analyses of breast milk, water, cow's milk, and dairy product samples from several of the Republics during the last decade, providing an opportunity for comparing the level of contamination to similar data from other countries. The general levels of contamination are similar to those observed in other countries. Social and economic conditions as well as the contamination of water and substitute foods in the Republics make alternative methods of infant feeding demonstrably less desirable for the child than the measured levels of breast milk contamination. PMID:8919605

  4. Environmental Research Translation: Enhancing Interactions with Communities at Contaminated Sites

    PubMed Central

    Ramirez-Andreotta, Monica D.; Brusseau, Mark L.; Artiola, Janick F.; Maier, Raina M.; Gandolfi, A. Jay

    2014-01-01

    The characterization and remediation of contaminated sites are complex endeavors fraught with numerous challenges. One particular challenge that is receiving increased attention is the development and encouragement of full participation by communities and community members affected by a given site in all facets of decision-making. Many disciplines have been grappling with the challenges associated with environmental and risk communication, public participation in environmental data generation, and decision-making and increasing community capacity. The concepts and methods developed by these disciplines are reviewed, with a focus on their relevance to the specific dynamics associated with environmental contamination sites. The contributions of these disciplines are then synthesized and integrated to help develop Environmental Research Translation (ERT), a proposed framework for environmental scientists to promote interaction and communication among involved parties at contaminated sites. This holistic approach is rooted in public participation approaches to science, which includes: a transdisciplinary team, effective collaboration, information transfer, public participation in environmental projects, and a cultural model of risk communication. Although there are challenges associated with the implementation of ERT, it is anticipated that application of this proposed translational science method could promote more robust community participation at contaminated sites. PMID:25173762

  5. Emerging Environmental Contaminants: Whats New

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise; for example, potential adverse health effects (e.g., cancer, reproductive and developmental effects, and endocrine disruption), bioaccumulation, an...

  6. Emerging Environmental Contaminants: What’s New

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise; for example, potential adverse health effects (e.g., cancer, reproductive and developmental effects, and endocrine disruption), bioaccumulation, an...

  7. Assessment of environmental contaminant-induced lymphocyte dysfunction.

    PubMed Central

    Silkworth, J B; Loose, L D

    1981-01-01

    Although it has been established that environmental contaminants can alter immune function, the mechanisms of action have yet to be determined. This paper reviews the effects of hydrocarbon environmental contaminants on lymphocyte function and presents an approach which may serve to delineate the mechanisms of action. The approach is based on the use of the developmental phases of an immune response and assays which can be used for their functional assessment. Possible interactions between environmental contaminants and lymphocyte function and factors which must be considered in the evaluation of immune status are discussed. In addition, a study on the influence of the chronic exposure to two polyhalogenated hydrocarbons, PCB and HCB, on several parameters of lymphocyte function in mice is presented. PMID:7016518

  8. Environmental and food contamination with PCB's in Japan.

    PubMed

    Fujiwara, K

    1975-09-01

    In Japan "yusho", i.e., poisoning caused by ingestion of rice oil contaminated with PCB's, broke out in October 1968, and produced more than 1200 officially certified cases. Nevertheless, it was only regarded as a kind of food poisoning and its connection with environmental and biological contamination was only imperfectly taken into consideration. Finally, in the autumn of 1970, two study groups, from the Ehime University and the Kyoto City Hygienic Institute, reported on the PCB contamination of salt water and fresh water fishes in Japan. Subsequently many reports about PCB's as an environmental contaminant have been published by several study groups throughout Japan, and nowadays the PCB polluted state of Japan has become rather clearly recognized. This report will present information on environmental, food and human contamination with PCB's in Japan especially also in some typically contaminated local areas, in addition to summarizing some overall aspects of the PCB problem in Japan (e.g., the production, shipment and use of PCB's). PMID:808853

  9. Challenges and trends in the determination of selected chemical contaminants and allergens in food.

    PubMed

    Krska, Rudolf; Becalski, Adam; Braekevelt, Eric; Koerner, Terry; Cao, Xu-Liang; Dabeka, Robert; Godefroy, Samuel; Lau, Ben; Moisey, John; Rawn, Dorothea F K; Scott, Peter M; Wang, Zhongwen; Forsyth, Don

    2012-01-01

    This article covers challenges and trends in the determination of some major food chemical contaminants and allergens, which-among others-are being monitored by Health Canada's Food Directorate and for which background levels in food and human exposure are being analyzed and calculated. Eleven different contaminants/contaminant groups and allergens have been selected for detailed discussion in this paper. They occur in foods as a result of: use as a food additive or ingredient; processing-induced reactions; food packaging migration; deliberate adulteration; and/or presence as a chemical contaminant or natural toxin in the environment. Examples include acrylamide as a food-processing-induced contaminant, bisphenol A as a food packaging-derived chemical, melamine and related compounds as food adulterants and persistent organic pollutants, and perchlorate as an environmental contaminant. Ochratoxin A, fumonisins, and paralytic shellfish poisoning toxins are examples of naturally occurring toxins whereas sulfites, peanuts, and milk exemplify common allergenic food additives/ingredients. To deal with the increasing number of sample matrices and analytes of interest, two analytical approaches have become increasingly prevalent. The first has been the development of rapid screening methods for a variety of analytes based on immunochemical techniques, utilizing ELISA or surface plasmon resonance technology. The second is the development of highly sophisticated multi-analyte methods based on liquid chromatography coupled with multiple-stage mass spectrometry for identification and simultaneous quantification of a wide range of contaminants, often with much less requirement for tedious cleanup procedures. Whereas rapid screening methods enable testing of large numbers of samples, the multi analyte mass spectrometric methods enable full quantification with confirmation of the analytes of interest. Both approaches are useful when gathering surveillance data to determine occurrence and background levels of both recognized and newly identified contaminants in foods in order to estimate human daily intake for health risk assessment. PMID:21773735

  10. Metamorphosis alters contaminants and chemical tracers in insects: implications for food webs

    USGS Publications Warehouse

    Kraus, Johanna M.; Walters, David M.; Wesner, Jeff S.; Stricker, Craig A.; Schmidt, Travis S.; Zuellig, Robert E.

    2014-01-01

    Insects are integral to most freshwater and terrestrial food webs, but due to their accumulation of environmental pollutants they are also contaminant vectors that threaten reproduction, development, and survival of consumers. Metamorphosis from larvae to adult can cause large chemical changes in insects, altering contaminant concentrations and fractionation of chemical tracers used to establish contaminant biomagnification in food webs, but no framework exists for predicting and managing these effects. We analyzed data from 39 studies of 68 analytes (stable isotopes and contaminants), and found that metamorphosis effects varied greatly. δ15N, widely used to estimate relative trophic position in biomagnification studies, was enriched by 1‰ during metamorphosis, while δ13C used to estimate diet, was similar in larvae and adults. Metals and polycyclic aromatic hydrocarbons (PAHs) were predominantly lost during metamorphosis leading to 2 to 125-fold higher larval concentrations and higher exposure risks for predators of larvae compared to predators of adults. In contrast, manufactured organic contaminants (such as polychlorinated biphenyls) were retained and concentrated in adults, causing up to 3-fold higher adult concentrations and higher exposure risks to predators of adult insects. Both food web studies and contaminant management and mitigation strategies need to consider how metamorphosis affects the movement of materials between habitats and ecosystems, with special regard for aquatic-terrestrial linkages.

  11. Bioassay-directed chemical analysis in environmental research

    SciTech Connect

    Schuetzle, D.; Lewtas, J.

    1986-01-01

    The use of short-term bioassay tests in conjunction with analytical measurements, constitute a powerful tool for identifying important environmental contaminants. The authors have coined the terminology bioassay directed chemical analysis to best describe this marriage of analytical chemistry and biology. The objective of this methodology is to identify key compounds in various types of air-pollutant samples. Once that task is completed, studies on metabolism, sources, environmental exposure and atmospheric chemistry can be undertaken. The principles and methodologies for bioassay directed chemical analysis are presented and illustrated in this paper. Most of this work has been directed toward the characterization of ambient air and diesel particulates, which are used as examples in this report to illustrate the analytical logic used for identifying the bio-active components of complex mixtures.

  12. Relative cancer risks of chemical contaminants in the great lakes

    NASA Astrophysics Data System (ADS)

    Bro, Kenneth M.; Sonzogni, William C.; Hanson, Mark E.

    1987-08-01

    Anyone who drinks water or eats fish from the Great Lakes consumes potentially carcinogenic chemicals. In choosing how to respond to such pollution, it is important to put the risks these contaminants pose in perspective. Based on recent measurements of carcinogens in Great Lakes fish and water, calculations of lifetime risks of cancer indicate that consumers of sport fish face cancer risks from Great Lakes contaminants that are several orders of magnitude higher than the risks posed by drinking Great Lakes water. But drinking urban groundwater and breathing urban air may be as hazardous as frequent consumption of sport fish from the Great Lakes. Making such comparisons is difficult because of variation in types and quality of information available and in the methods for estimating risk. Much uncertainty pervades the risk assessment process in such areas as estimating carcinogenic potency and human exposure to contaminants. If risk assessment is to be made more useful, it is important to quantify this uncertainty.

  13. enviPath – The environmental contaminant biotransformation pathway resource

    PubMed Central

    Wicker, Jörg; Lorsbach, Tim; Gütlein, Martin; Schmid, Emanuel; Latino, Diogo; Kramer, Stefan; Fenner, Kathrin

    2016-01-01

    The University of Minnesota Biocatalysis/Biodegradation Database and Pathway Prediction System (UM-BBD/PPS) has been a unique resource covering microbial biotransformation pathways of primarily xenobiotic chemicals for over 15 years. This paper introduces the successor system, enviPath (The Environmental Contaminant Biotransformation Pathway Resource), which is a complete redesign and reimplementation of UM-BBD/PPS. enviPath uses the database from the UM-BBD/PPS as a basis, extends the use of this database, and allows users to include their own data to support multiple use cases. Relative reasoning is supported for the refinement of predictions and to allow its extensions in terms of previously published, but not implemented machine learning models. User access is simplified by providing a REST API that simplifies the inclusion of enviPath into existing workflows. An RDF database is used to enable simple integration with other databases. enviPath is publicly available at https://envipath.org with free and open access to its core data. PMID:26582924

  14. Environmental contaminant studies by the Patuxent Wildlife Research Center

    USGS Publications Warehouse

    Heinz, G.H.; Hill, E.F.; Stickel, W.H.; Stickel, L.F.

    1979-01-01

    Evaluation of the effects of environmental contaminants on wildlife is geared to interpreting events in the field, especially population effects, and both field and laboratory studies are planned for this purpose; procedures are adapted to specific problems and therefore do not include strict protocols or routine testing. Field evaluations include measurements of cholinesterase inhibition in brain or blood, search for dead or disabled animals, study of nesting success of birds, and general ecological observations. Residue analyses are used in evaluating organochlorine chemicals; samples may include whole bodies for determining level of exposure, brains for mortality diagnosis, whole blood for certain special studies, and eggs to help in evaluation of possible reproductive effects. Bird counts, singing-male census counts, small mamrnal trapping, and cage-in-field tests have proven to be ineffective or misleading and are not considered suitable for field evaluations under most circumstances. Usefulness of simulated field trials is limited to very special situations. Experimental studies that help predict and interpret field effects include determinations of lethal diagnostic levels, comparative lethal dietary toxicity tests, tests of secondary poisoning measurement of residue loss rates, measurement of blood enzymes, tests of behavioral effects, and studies of reproductive effects.

  15. enviPath - The environmental contaminant biotransformation pathway resource.

    PubMed

    Wicker, Jrg; Lorsbach, Tim; Gtlein, Martin; Schmid, Emanuel; Latino, Diogo; Kramer, Stefan; Fenner, Kathrin

    2016-01-01

    The University of Minnesota Biocatalysis/Biodegradation Database and Pathway Prediction System (UM-BBD/PPS) has been a unique resource covering microbial biotransformation pathways of primarily xenobiotic chemicals for over 15 years. This paper introduces the successor system, enviPath (The Environmental Contaminant Biotransformation Pathway Resource), which is a complete redesign and reimplementation of UM-BBD/PPS. enviPath uses the database from the UM-BBD/PPS as a basis, extends the use of this database, and allows users to include their own data to support multiple use cases. Relative reasoning is supported for the refinement of predictions and to allow its extensions in terms of previously published, but not implemented machine learning models. User access is simplified by providing a REST API that simplifies the inclusion of enviPath into existing workflows. An RDF database is used to enable simple integration with other databases. enviPath is publicly available at https://envipath.org with free and open access to its core data. PMID:26582924

  16. Which coastal and marine environmental contaminants are truly emerging?

    PubMed

    Maruya, Keith A; Dodder, Nathan G; Tang, Chi-Li; Lao, Wenjian; Tsukada, David

    2015-02-01

    To better understand the past and present impact of contaminants of emerging concern (CECs) in coastal and marine ecosystems, archived samples were analyzed for a broad suite of analytes, including pharmaceuticals and personal care products (PPCPs), flame retardants (including PBDEs), perfluorinated compounds (PFCs), and current-use pesticides. Surface sediment, mussels (Mytilus spp.) and sediment core samples collected from the California (USA) coast were obtained from environmental specimen banks. Selected CECs were detected in recent surface sediments, with nonylphenol (4-NP), its mono- and di-ethoxylates (NP1EO and NP2EO), triclocarban, and pyrethroid insecticides in the greatest abundance. Alkylphenols, triclocarban, and triclosan were present in sediment core segments from the 1970s, as well as in Mytilus tissue collected during the 1990s. Increasing concentrations of some CECs (e.g., miconazole, triclosan) were observed in the surface layers (ca. 2007) of a sediment core, in contrast to peak concentrations of 4-NP and triclocarban corresponding to input during the 1970s, and an apparent peak input for PBDEs during the 1990s. These results suggest that chemicals sometimes referred to as "emerging" (e.g., alkylphenols, triclocarban) have been present in the aquatic environment for several decades and are decreasing in concentration, whereas others (e.g., miconazole, triclosan) are increasing. PMID:24743956

  17. Chemical oxidation of contaminants in clay or sandy soil

    SciTech Connect

    Gates, D.D.; Cline, S.R.; Siegrist, R.L.

    1995-11-01

    This paper describes laboratory studies conducted at Oak Ridge National Laboratory (ORNL), investigating the feasibility of the application of low-strength hydrogen peroxide (H{sub 2}O{sub 2}) or potassium permanganate (KMnO{sub 4}) solutions to remediate soil contaminated with volatile organic compounds (VOCs). A statistically designed screening study was completed that evaluated the effect of several factors on chemical oxidation treatment efficiency. This study revealed that the most important factors include oxidant type, oxidant concentration, reaction time and soil type. Using the optimum treatment conditions, greater than 90% reduction of trichloroethylene (TCE) and perchloroethylene (PCE) was achieved using in situ chemical oxidation.

  18. Birds and environmental contaminants in San Francisco and Chesapeake Bays

    USGS Publications Warehouse

    Ohlendorf, H.M.; Fleming, W.J.

    1988-01-01

    The direct and indirect effects of human activities, including environmental contamination, upon bird populations in San Francisco Bay and Chesapeake Bay are imperfectly understood, and few data are available. that allow a comparison of the contamination levels in birds from these two areas. Certain trace elements and organochlorine compounds have been found at sufficiently high concentrations in bird tissues or their foods to expect adverse effects in these birds, based upon results of field and laboratory studies conducted with other avian species. The decline and recovery of populations of many avian species have been recorded, including some associated with organochlorine contamination. The present paper summarizes available information on the occurrence and potential effects of contaminants upon birds in these two regions.

  19. Decontamination of heavy metal-contaminated soils by chemical extraction

    SciTech Connect

    Huang, W.M.; Gavaskar, A.; Ong, S.K.

    1994-12-31

    Chemical extraction is an emerging remedial technology for the decontamination of soils contaminated with inorganic pollutants such as heavy metals. In this study, various chemicals were evaluated to determine their effectivenesses in removing lead (Pb), copper (Cu), and zinc (Zn) from a heavy metal-contaminated soil. Extraction chemicals tested were nitric acid (HNO{sub 3}), two chelating agents (nitrilotriacetic acid, NTA and ethylenediaminetetraacetic acid, EDTA), and combinations of NTA or EDTA with sodium citrate (NaCit). Solutions of EDTA and EDTA/NaCit were buffered at pH 7.0. Contaminated soil used in this study was silty sand with concentrations of Pb, Cu, and Zn as high as 40,000, 1,500, and 200 mg/Kg, respectively, for soil fractions less than 10 mesh. Maximum removal of Pb were 99.13%, 98.35%, 98.88%, 75.82%, and 68.60% using 1 {und M} HNO{sub 3}, 0.1 {und M} EDTA, 0.1 {und M} EDTA/0.1 {und M} NaCit, 0.1 {und M} NTA, and 0.01 M NTA/0.1 {und M} NaCit, respectively. HNO{sub 3} and EDTA was found to be more effective at removing Cu and Pb than Zn. EDTA/NaCit were slightly more efficient than EDTA alone at the extraction of Pb, Cu, and Zn. NTA and NTA/NaCit were the least effective extractants among those agents tested, especially for Pb extraction. HNO{sub 3} and EDTA/NaCit appear to be the promising extracting agents for the decontamination of heavy metal-contaminated soils. An advantage of using EDTA/NaCit over HNO{sub 3} is that handling/storing of corrosive liquids is minimized.

  20. Implications of chemical contaminants for aquatic animals in the Canadian arctic: some review comments.

    PubMed

    Lockhart, W L

    1995-01-15

    Chemical residue analyses have established beyond doubt that arctic ecosystems are contaminated with low concentrations of several contaminants. The sources of these vary, but for many, the principal source is atmospheric deposition as a result of widespread dispersal by air masses carrying materials from lower latitudes. The principal problem discussed here is how to determine whether there are biological implications associated with the contaminants. For the most part, concentrations are below those found in more temperate regions where similar questions have been asked. Little experimental toxicology has been done with arctic species, and relatively little has been done in environmental toxicology in general to express biological responses in terms of body residues. It is argued that chemical residue studies are not, in themselves, evidence of biological responses. The effects of greatest interest are those at ecological levels, but ecological surveys that might detect biological changes have little power to test for cause-effect linkages between the contaminants and the changes observed. The emerging approach of biomarkers or bioindicators seems to offer the greatest promise for efforts to determine whether arctic contaminants have biological implications. PMID:7892589

  1. Chemical Aging of Environmentally Friendly Cleaners

    NASA Technical Reports Server (NTRS)

    Biegert, L. L.; Evans, K. B.; Olsen, B. D.; Weber, B. L.

    2001-01-01

    Use of cleaners in the manufacturing area demands bottles that will hold a sufficient amount of material and allow for easy and controlled dispensing by the operator without contamination or material leaching from the bottle. The manufacturing storage conditions are also a factor that may affect cleaner chemical integrity and its potential to leave a residue on the part. A variety of squeeze bottles stored in mild (72 F, 10% R.H., dark) and harsh (105 F, 50% R.H., fluorescent lighting) conditions were evaluated to determine the effect of environment and bottle exposure on ozone depleting chemicals (ODC) cleaners chemical composition. Low Density Polyethylene (LDPE) bottles were found to be quite permeable to all the cleaners evaluated in this study indicating this bottle type should not be used in the manufacturing area. Fluorinated Polyethylene (FLPE) bottles showed little cleaner loss and change in cleaner chemical composition over time suggesting these bottles would be acceptable for use. Chemical analysis indicates limonene containing cleaners show increased non-volatile residue (NVR) content with storage under harsh conditions. Some cleaners use BHT (butylated hydroxytoluene) as stabilizer and to protect against limonene oxidation. Under harsh conditions, BHT was quickly depleted resulting in higher NVR levels.

  2. Pharmaceuticals as Environmental Contaminants: An Overview of the Science

    EPA Science Inventory

    Over the last decade, a new dimension to environmental pollution has become evident C one involving the actions, behaviors, and activities of the individual consumer as a source of chemical pollutants. A major focus on consumer-use chemicals has been directed at the numerous type...

  3. FINGERPRINT ANALYSIS OF CONTAMINANT DATA: A FORENSIC TOOL FOR EVALUATING ENVIRONMENTAL CONTAMINATION

    EPA Science Inventory

    Several studies have been conducted on behalf of the U .S. Environmental Protection Agency (EPA) to identify detection monitoring parameters for specific industries.1,2,3,4,5 One outcome of these studies was the evolution of an empirical multi-variant contaminant fingerprinting p...

  4. Chemical and toxicological testing of composted explosives-contaminating soil

    SciTech Connect

    Griest, W.H.; Steward, A.J.; Tyndall, R.L.; Caton, J.E.; Ho, C.H.; Ironside, K.S.; Caldwell, W.M.; Tan, E. )

    1993-06-01

    Static-pile and mechanically stirred composts of explosives-contaminated soil at the Umatilla Army Depot Activity (UMDA, Umatilla, OR) in a field composting optimization study were characterized chemically and toxicologically. The concentrations of extractable explosives (e.g., 2,4,6-trinitrotoluene) in the composts and their aqueous leachates, the mutagenicity of organic solvent extracts from the composts, and the toxicity of compost aqueous leachates to Ceriodaphnia dubia all decreased considerably with 20 d of composting. After 44 d or 90 d of composting, the toxicity, mutagenicity, and concentrations of extractable explosives decreased more than 90% in some cases. The composting efficiency was generally inversely proportional to the percentage (v/v) of contaminated soil. Composting in static piles was efficient up to about 20% (v/v) of contaminated soil; composting in the mechanically stirred composters was efficient up to about 25% soil. Mechanical composting was more efficient than composting in static piles. The main conclusion of this study is that composting can effectively remediate explosives contaminated soil and sediment. However, low levels of explosives and metabolites, bacterial mutagenicity, and leachable toxicity to Ceriodaphnia may remain after composting. The sources of residual toxicity and mutagenicity and the ultimate fate of the explosives are unknown.

  5. Chemical disinfection of human rotavirus-contaminated inanimate surfaces.

    PubMed Central

    Lloyd-Evans, N.; Springthorpe, V. S.; Sattar, S. A.

    1986-01-01

    Fomites may play a role in the transmission of rotavirus infections, and in view of this, 27 disinfectants were evaluated for their ability to inactivate human rotavirus (HRV) on contaminated non-porous inanimate surfaces. Disks of stainless steel, glass and two types of plastics were contaminated with about 10(7) plaque-forming units of HRV suspended in faecal matter. The inoculum was allowed to dry and an equal volume of the product under test was applied to the contaminated surface. After contact for 1 min, the action of the disinfectant was stopped by dilution. Surviving infectious virus on the disks was determined by plaque assay in MA-104 cells. A product was considered to be effective if it could reduce the virus titre by at least 3 log10. Only 33.3% (9/27) of the formulations tested proved to be effective. Further testing of the effective products, which included antiseptics, instrument soaks and hard-surface disinfectants, showed that all of them could, in fact, reduce the virus titre on contaminated surfaces by at least 6 log10. These findings show the relative resistance of HRV to a wide range of chemical disinfectants in common use, and also emphasize the need for a more thorough evaluation of the virucidal potential of formulations regularly employed in attempts to prevent and control outbreaks of rotaviral diarrhoea. PMID:3016082

  6. Environmental projects. Volume 14: Removal of contaminated soil and debris

    NASA Technical Reports Server (NTRS)

    Kushner, Len

    1992-01-01

    Numerous diverse activities at the Goldstone Deep Space Communications Complex (GDSCC) are carried out in support of six parabolic dish antennas. Some of these activities can result in possible spills or leakages of hazardous materials and wastes stored both above ground in steel drums and below ground in underground storage tanks (UST's). These possible leaks or spills, along with the past practice of burial of solid debris and waste in trenches and pits, could cause local subsurface contamination of the soil. In 1987, the Jet Propulsion Laboratory (JPL), retained Engineering-Science, Inc. (E-S), Pasadena, California, to identify the specific local areas within the GDSCC with subsurface soil contamination. The E-S study determined that some of the soils at the Apollo Site and the Mars Site were contaminated with hydrocarbons, while soil at a nonhazardous waste dumpsite at the Mojave Base site was contaminated with copper. This volume is a JPL-expanded version of the PE209 E-S report, and it also reports that all subsurface contaminated soils at the GDSCC were excavated, removed, and disposed of in an environmentally acceptable way, and the excavations were backfilled and covered in accordance with accepted Federal, State, and local environmental rules and regulations.

  7. Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

    NASA Astrophysics Data System (ADS)

    Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

    2006-09-01

    An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22cm diameter and 30cm length, purifies an airflow rate of 5000lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application.

  8. Plasma flame for mass purification of contaminated air with chemical and biological warfare agents

    SciTech Connect

    Uhm, Han S.; Shin, Dong H.; Hong, Yong C.

    2006-09-18

    An elimination of airborne simulated chemical and biological warfare agents was carried out by making use of a plasma flame made of atmospheric plasma and a fuel-burning flame, which can purify the interior air of a large volume in isolated spaces such as buildings, public transportation systems, and military vehicles. The plasma flame generator consists of a microwave plasma torch connected in series to a fuel injector and a reaction chamber. For example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies an airflow rate of 5000 lpm contaminated with toluene (the simulated chemical agent) and soot from a diesel engine (the simulated aerosol for biological agents). Large volumes of purification by the plasma flame will free mankind from the threat of airborne warfare agents. The plasma flame may also effectively purify air that is contaminated with volatile organic compounds, in addition to eliminating soot from diesel engines as an environmental application.

  9. Analysis of Food Contaminants, Residues, and Chemical Constituents of Concern

    NASA Astrophysics Data System (ADS)

    Ismail, Baraem; Reuhs, Bradley L.; Nielsen, S. Suzanne

    The food chain that starts with farmers and ends with consumers can be complex, involving multiple stages of production and distribution (planting, harvesting, breeding, transporting, storing, importing, processing, packaging, distributing to retail markets, and shelf storing) (Fig. 18.1). Various practices can be employed at each stage in the food chain, which may include pesticide treatment, agricultural bioengineering, veterinary drug administration, environmental and storage conditions, processing applications, economic gain practices, use of food additives, choice of packaging material, etc. Each of these practices can play a major role in food quality and safety, due to the possibility of contamination with or introduction (intentionally and nonintentionally) of hazardous substances or constituents. Legislation and regulation to ensure food quality and safety are in place and continue to develop to protect the stakeholders, namely farmers, consumers, and industry. [Refer to reference (1) for information on regulations of food contaminants and residues.

  10. NATIONAL REPORT ON HUMAN EXPOSURE TO ENVIRONMENTAL CHEMICALS

    EPA Science Inventory

    The National Report on Human Exposure to Environmental Chemicals is a new publication that will provide an ongoing assessment of the U.S. population's exposure to environmental chemicals using biomonitoring. For this Report, an environmental chemical means a chemical compound or ...

  11. Osprey: worldwide sentinel species for assessing and monitoring environmental contamination in rivers, lakes, reservoirs, and estuaries.

    PubMed

    Grove, Robert A; Henny, Charles J; Kaiser, James L

    2009-01-01

    In the United States, many fish and wildlife species have been used nationwide to monitor environmental contaminant exposure and effects, including carcasses of the bald eagle (Haliaeetus leucocephalus), the only top avian predator regularly used in the past. Unfortunately, bald eagles are sensitive to investigator intrusion at the nest. Thus, the osprey (Pandion haliaetus) is evaluated as a potential sentinel species for aquatic ecosystems. Several characteristics support the choice of the osprey as a sentinel species, including: (1) fish-eating diet atop the aquatic food web, (2) long-lived with strong nest fidelity, (3) adapts to human landscapes (potentially the most contaminated), (4) tolerates short-term nest disturbance, (5) nests spatially distributed at regular intervals, (6) highly visible nests easily located for study, (7) ability to accumulate most, if not all, lipophilic contaminants, (8) known sensitivity to many contaminants, and (9) nearly a worldwide distribution. These osprey traits have been instrumental in successfully using the species to understand population distribution, abundance, and changes over time; the effects of various contaminants on reproductive success; how contaminants in prey (fish on biomass basis) contribute to egg concentrations (i.e., biomagnification factors); and spatial residue patterns. Data summarized include nesting population surveys, detailed nesting studies, and chemical analyses of osprey egg, organ, blood, and feather samples for contaminants that bioaccumulate and/or biomagnify in aquatic food webs; and biochemical evaluations of blood and various organs. Studies in the United States, Canada, Mexico, Europe, and elsewhere have shown the osprey to be a useful sentinel species for monitoring selected environmental contaminants, including some emerging contaminants in lakes, reservoirs, rivers, and estuaries. PMID:19117208

  12. Characterization of sea surface chemical contamination after shipping accidents.

    PubMed

    Guitart, Carlos; Frickers, Patricia; Horrillo-Caraballo, Jose; Law, Robin J; Readman, James W

    2008-04-01

    A contamination survey was conducted after the beaching of the stricken cargo ship MSC Napoli in Lyme Bay on the south coast of Devon (UK). A grid of 22 coastal and offshore stations was sampled to investigate the extent of spilled oil and to screen for chemical contamination, as well as to evaluate the behavior of the oil at the air-sea interface. Samples were collected from the sea surface microlayer (SML) and from subsurface waters (SSW) at each station. The fuel oil spilled (IFO 380) was also analyzed. The determination of oil-related hydrocarbons (aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), terpanes, and steranes) and the screening for other harmful chemicals on the inventory of the MSC Napoli in the seawater samples, was performed by PTV-GC/ MS using large volume injection (LVI) techniques. Screening did not reveal the presence of any harmful chemicals other than petroleum-related compounds. Results afforded investigation of oil sources and spatial distributions of total PAH concentrations and enrichments in the sea surface microlayer (SML). Rather than a single source, oil fingerprinting analyses of the samples revealed a mixture of three types of oil: heavy fuel oil, lubricating oil, and a lighter oil (probably diesel oil). Enrichment factors (EF) in the SML (EF = C(SML)/C(SSW)) were calculated and, in the vicinity of the ship, approached 2000, declining with distance away from the wreck. These factors represent approximately a 1000-fold enrichment over typical coastal total PAH enrichments in the SML and reflected a clear petrogenic origin of the contamination (as demonstrated, for example, by a Fl/Pgamma ratio < 1). In addition, the spatial transport and fate (i.e., air-sea exchange processes and water column diffusion) of the oil-related hydrocarbons in the sea surface were investigated. Essentially, near the wreck, the SML was highly enriched in oil forming a visible sheen, both disrupting the normal air-seawater exchange processes and generating a downward diffusion flux of contaminants from the SML to the SSW. This was reflected by a higher occurrence of naphthalene relative to alkyl-naphthalenes in the SSW compared to the SML. The higher concentrations and different sources of oil found in the SML in comparison to those found in the SSW indicate that, if only subsurface water samples are investigated in isolation, the true extent and impact of a spill could be underestimated. It is important to simultaneously evaluate contamination in the sea surface during emergency response. PMID:18504953

  13. Role of Environmental Contaminants in the Etiology of Alzheimer's Disease: A Review

    PubMed Central

    Manivannan, Yegambaram; Manivannan, Bhagyashree; Beach, Thomas G.; Halden, Rolf U.

    2015-01-01

    Alzheimer's dis ease (AD) is a leading cause of mortality in the developed world with 70% risk attributable to genetics. The remaining 30% of AD risk is hypothesized to include environmental factors and human lifestyle patterns. Environmental factors possibly include inorganic and organic hazards, exposure to toxic metals (aluminium, copper), pesticides (organochlorine and organophosphate insecticides), industrial chemicals (flame retardants) and air pollutants (particulate matter). Long term exposures to these environmental contaminants together with bioaccumulation over an individual's life-time are speculated to induce neuroinflammation and neuropathology paving the way for developing AD. Epidemiologic associations between environmental contaminant exposures and AD are still limited. However, many in vitro and animal studies have identified toxic effects of environmental contaminants at the cellular level, revealing alterations of pathways and metabolisms associated with AD that warrant further investigations. This review provides an overview of in vitro, animal and epidemiological studies on the etiology of AD, highlighting available data supportive of the long hypothesized link between toxic environmental exposures and development of AD pathology. PMID:25654508

  14. Role of environmental contaminants in the etiology of Alzheimer's disease: a review.

    PubMed

    Yegambaram, Manivannan; Manivannan, Bhagyashree; Beach, Thomas G; Halden, Rolf U

    2015-01-01

    Alzheimer's dis ease (AD) is a leading cause of mortality in the developed world with 70% risk attributable to genetics. The remaining 30% of AD risk is hypothesized to include environmental factors and human lifestyle patterns. Environmental factors possibly include inorganic and organic hazards, exposure to toxic metals (aluminium, copper), pesticides (organochlorine and organophosphate insecticides), industrial chemicals (flame retardants) and air pollutants (particulate matter). Long term exposures to these environmental contaminants together with bioaccumulation over an individual's life-time are speculated to induce neuroinflammation and neuropathology paving the way for developing AD. Epidemiologic associations between environmental contaminant exposures and AD are still limited. However, many in vitro and animal studies have identified toxic effects of environmental contaminants at the cellular level, revealing alterations of pathways and metabolisms associated with AD that warrant further investigations. This review provides an overview of in vitro, animal and epidemiological studies on the etiology of AD, highlighting available data supportive of the long hypothesized link between toxic environmental exposures and development of AD pathology. PMID:25654508

  15. A combined chemical and biological assessment of industrial contamination in an estuarine system in Kerala, India.

    PubMed

    Dsikowitzky, Larissa; Nordhaus, Inga; Sujatha, C H; Akhil, P S; Soman, Kunjupilai; Schwarzbauer, Jan

    2014-07-01

    The Cochin Backwaters in India are part of the Vembanad-Kol system, which is a protected wetland and one of the largest estuarine ecosystems in South Asia. The backwaters are a major supplier of fisheries resources and are developed as tourist destination. Periyar River discharges into the northern arm of the system and receives effluents from chemical, petrochemical and metal processing industries which release huge amounts of wastewaters after little treatment. We investigated water and sediment contamination in the industrial vicinity and at one station further away including organic and inorganic contaminants. In total 83 organic contaminants were found, e.g. well known priority pollutants such as endosulfan, hexachlorobenzene, DDT, hexachlorocyclohexane and their metabolites, which likely stem from the industrial manufacturing of organochlorine pesticides. Furthermore, several benzothiazole, dibenzylamine and dicyclohexylamine derivatives were detected, which indicated inputs from rubber producing facilities. Several of these compounds have not been reported as environmental contaminants so far. A comparison of organic contaminant and trace hazardous element concentrations in sediments with reported sediment quality guidelines revealed that adverse effects on benthic species are likely at all stations. The chemical assessment was combined with an investigation of macrobenthic diversity and community composition. Benthic organisms were completely lacking at the site with the highest trace hazardous element concentrations. Highest species numbers, diversity indices and abundances were recorded at the station with the greatest distance to the industrial area. Filter feeders were nearly completely lacking, probably leading to an impairment of the filter function in this area. This study shows that a combination of chemical and biological methods is an innovative approach to achieve a comprehensive characterization of industrial contamination, to evaluate associated risks for bottom dwelling consumers regarding sediment quality guidelines, and to observe related adverse effects on the benthic community directly in the field. PMID:24735943

  16. Microarray Technology for Major Chemical Contaminants Analysis in Food: Current Status and Prospects

    PubMed Central

    Zhang, Zhaowei; Li, Peiwu; Hu, Xiaofeng; Zhang, Qi; Ding, Xiaoxia; Zhang, Wen

    2012-01-01

    Chemical contaminants in food have caused serious health issues in both humans and animals. Microarray technology is an advanced technique suitable for the analysis of chemical contaminates. In particular, immuno-microarray approach is one of the most promising methods for chemical contaminants analysis. The use of microarrays for the analysis of chemical contaminants is the subject of this review. Fabrication strategies and detection methods for chemical contaminants are discussed in detail. Application to the analysis of mycotoxins, biotoxins, pesticide residues, and pharmaceutical residues is also described. Finally, future challenges and opportunities are discussed. PMID:23012541

  17. Raman-spectroscopy-based chemical contaminant detection in milk powder

    NASA Astrophysics Data System (ADS)

    Dhakal, Sagar; Chao, Kuanglin; Qin, Jianwei; Kim, Moon S.

    2015-05-01

    Addition of edible and inedible chemical contaminants in food powders for purposes of economic benefit has become a recurring trend. In recent years, severe health issues have been reported due to consumption of food powders contaminated with chemical substances. This study examines the effect of spatial resolution used during spectral collection to select the optimal spatial resolution for detecting melamine in milk powder. Sample depth of 2mm, laser intensity of 200mw, and exposure time of 0.1s were previously determined as optimal experimental parameters for Raman imaging. Spatial resolution of 0.25mm was determined as the optimal resolution for acquiring spectral signal of melamine particles from a milk-melamine mixture sample. Using the optimal resolution of 0.25mm, sample depth of 2mm and laser intensity of 200mw obtained from previous study, spectral signal from 5 different concentration of milk-melamine mixture (1%, 0.5%, 0.1%, 0.05%, and 0.025%) were acquired to study the relationship between number of detected melamine pixels and corresponding sample concentration. The result shows that melamine concentration has a linear relation with detected number of melamine pixels with correlation coefficient of 0.99. It can be concluded that the quantitative analysis of powder mixture is dependent on many factors including physical characteristics of mixture, experimental parameters, and sample depth. The results obtained in this study are promising. We plan to apply the result obtained from this study to develop quantitative detection model for rapid screening of melamine in milk powder. This methodology can also be used for detection of other chemical contaminants in milk powders.

  18. Chemical Aging of Environmentally Friendly Cleaners

    NASA Technical Reports Server (NTRS)

    Evans, K.; Biegert, L.; Olsen, B.; Weber, B.; McCool, Alex (Technical Monitor)

    2001-01-01

    Use of cleaners in the manufacturing area demands bottles that will hold a sufficient amount of material and allow for easy and controlled dispensing by the operator without contamination or material leaching from the bottle. The manufacturing storage conditions are also a factor that may affect cleaner chemical integrity and its potential to leave a residue on the part. A variety of squeeze bottles stored in mild (72 F, 10 % R.H., dark) and harsh (105 F, 50 % R.H., fluorescent lighting) conditions were evaluated to determine the effect of environment and bottle exposure on the chemical composition of TCA (1,1,1 trichloroethane) replacement solvents. Low Density Polyethylene (LDPE) bottles were found to be quite permeable to all the cleaners evaluated in this study indicating this bottle type should not be used in the manufacturing area. Fluorinated Polyethylene (FLPE) bottles showed little cleaner loss and change in cleaner chemical composition over time suggesting these bottles would be acceptable for use. Chemical analysis indicates limonene-containing cleaners show increased non-volatile residue (NVR) content with storage under harsh conditions. Some cleaners use BHT (butylated hydroxytoluene) as stabilizer and to protect against limonene oxidation. Under harsh conditions, BHT was quickly depleted resulting in higher NVR levels.

  19. Allergic contact sensitizing chemicals as environmental carcinogens.

    PubMed Central

    Albert, R E

    1997-01-01

    Chemicals that were bioassayed by the National Toxicology Program (NTP) and that also produce allergic dermatitis (ACD) in humans were evaluated for their tumorigenic characteristics. The impetus for the study was that most contact sensitizers, i.e., those that produce ACD, and genotoxic carcinogens are chemically similar in that they are electrophilic, thereby producing adducts on macromolecules including protein and DNA. This similarity in chemical behavior suggests that many contact sensitizers might be environmental carcinogens. All of the published NTP bioassays by early 1996 that had both genotoxicity and carcinogenicity studies were included in this analysis. The NTP chemicals had been chosen for bioassay without regard to their ability to produce ACD. Of the 209 chemicals that were bioassayed, there were 36 (17%) that were known to be human contact sensitizers; about half of these were positive on tumor bioassays. The contact sensitizers differed from the NTP sample as a whole by having a proportionately larger number of nongenotoxic chemicals by the Ames Salmonella assay, presumably because more of them were selected on the basis of widespread usage rather than structural resemblance to known carcinogens. Compared to the nongenotoxic chemicals, the genotoxics were stronger carcinogens in that they had a higher incidence of positive tumor bioassays, with twice the number of organs in which tumors were induced. The nongenotoxic chemicals had a preference for tumor induction in parenchymal tissues in contrast to epithelial tissues. The contact sensitizers showed essentially the same characteristics as the whole NTP sample when stratified according to genotoxicity. Judging by the chemicals that were chosen primarily for their widespread use rather than for their structural resemblance to carcinogens, the addition of a test for contact sensitization to the Ames test as a screening tool would increase the tumorigenic detection efficiency by about 40% because of the nongenotoxic tumorigens. A ballpark estimate suggests that there could be several thousand contact sensitizers for humans in commercial use that are rodent tumorigens. Images Figure 1. PMID:9300923

  20. Considerations involved with the use of semipermeable membrane devices for monitoring environmental contaminants

    USGS Publications Warehouse

    Petty, J.D.; Orazio, C.E.; Huckins, J.N.; Gale, R.W.; Lebo, J.A.; Meadows, J.C.; Echols, K.R.; Cranor, W.L.

    2000-01-01

    Semipermeable membrane devices (SPMDs) are used with increasing frequency, and throughout the world as samplers of organic contaminants. The devices can be used to detect a variety of lipophilic chemicals in water, sediment/soil, and air. SPMDs are designed to sample nonpolar, hydrophobic chemicals. The maximum concentration factor achievable for a particular chemical is proportional to its octanol-water partition coefficient. Techniques used for cleanup of SPMD extracts for targeted analytes and for general screening by full-scan mass spectrometry do not differ greatly from techniques used for extracts of other matrices. However, SPMD extracts contain potential interferences that are specific to the membrane-lipid matrix. Procedures have been developed or modified to alleviate these potential interferences. The SPMD approach has been demonstrated to be applicable to sequestering and analyzing a wide array of environmental contaminants including organochlorine pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, polychlorinated dioxins and dibenzofurans, selected organophosphate pesticides and pyrethroid insecticides, and other nonpolar organic chemicals. We present herein an overview of effective procedural steps for analyzing exposed SPMDs for trace to ultra-trace levels of contaminants sequestered from environmental matrices. Copyright (C) 2000.

  1. Alterations in macrophage functions by environmental chemicals.

    PubMed Central

    Gardner, D E

    1984-01-01

    The establishment of infectious diseases is rarely entirely attributed to a single entity, but instead is the result of a primary stress and one or more secondary factors that interfere with homeostasis and the ability of the host to cope with the primary etiologic assault. Any environmental chemical that can suppress the normal functioning of the host's body defenses would be expected to increase the risk of the host to such diseases. Within the lung, the alveolar macrophages are the crucial elements responsible for defending the body against such airborne viable agents. The effects of inhaled gases and particulates on these defense cells are a major concern of the environmental health scientist since such chemicals have the capability of adversely affecting the integrity and functioning of these pulmonary defense cells. The objective of this report is to provide an overview that will improve our understanding of how a variety of environmental chemicals can alter the biochemical, physiological and immunological functioning of these cells. PMID:6376106

  2. Chronic toxicity of environmental contaminants: sentinels and biomarkers.

    PubMed Central

    LeBlanc, G A; Bain, L J

    1997-01-01

    Due to the use of a limited number of species and subchronic exposures, current ecological hazard assessment processes can underestimate the chronic toxicity of environmental contaminants resulting in adverse responses of sentinel species. Several incidences where sentinel species have responded to the effects of chronic exposure to ambient levels of environmental contaminants are discussed, including the development of neoplasia in fish, immunosuppression in marine mammals, pseudohermaphrodism in invertebrates, teratogenicity in amphibians, and aberrations in the sexual development of fish and reptiles. Biomarkers of chronic toxicity, including DNA mutations, alterations in specific protein and mRNA levels, and perturbations in metabolism, are presented. The incorporation of appropriate surrogate species and biomarkers of chronic toxicity into standard toxicity characterizations is proposed as a means of significantly refining the ecological hazard assessment process. PMID:9114278

  3. Environmental contamination of groundwater in the Gaza Strip

    NASA Astrophysics Data System (ADS)

    Al-Agha, M. R.

    1995-03-01

    Environmental problems of groundwater contamination in the Gaza Strip are summarized in this paper. The Gaza Strip is a very narrow and highly populated area along the coast of the Mediterranean Sea (360 km2). Human activities greatly threaten the groundwater resources in the area, while the unconfined nature of some parts of the coastal main aquifer favors groundwater contamination. Recent investigations show contamination of the aquifer with organic substances from detergents, agrochemicals, sewage (cesspools), and waste degradation. These effects enhance each other because there is no recycling industry, sewage system, or any type of environmental protection management at present. Inorganic contamination results from overpumping, which increases the salinity of the groundwater. Seawater intrusion also increases the salinity of the groundwater that are used for drinking and agricultural purposes. Consequently, at present about 80 percent of the groundwater in the Gaza Strip is unfit for both human and animal consumption. Solutions are very urgently needed for these problems in order to prevent the spread of dangerous diseases.

  4. REMOVAL OF ORGANIC CCL CONTAMINANTS FROM DRINKING WATERS BY ENHANCED COAGULATION, POWDERED ACTIVATED CARBON, CHEMICAL SOFTENING, AND OXIDATION

    EPA Science Inventory

    The 1996 amendments to the Safe Drinking Water Act (SWDA) require the US Environmental Protection Agency (USEPA) to establish a list of unregulated microbiological and chemical contaminants to aid in priority-setting for the Agency's drinking water program. This list, known as t...

  5. DETERMINATION OF ENVIRONMENTAL CONTAMINANTS USING AN ELECTROSPRAY INTERFACE COMBINED WITH AN ION TRAP MASS SPECTROMETER

    EPA Science Inventory

    The U.S. Environmental Protection Agency, through its Office of Research and Development, was interested in determining environmental contaminants using a commercial electrospray which is interfaced to an ion trap mass spectrometer (ITMS) to analyze contaminants of concern. ptimi...

  6. Changes in chemical contaminant body burden and biological effects in mussels adjacent to a marine remediation site

    SciTech Connect

    Kagley, A.N.; Snider, R.G.; Inouye, L.S.; Casillas, E.

    1995-12-31

    Eagle Harbor is a creosote-polluted marine site currently undergoing initial environmental remediation. Highly contaminated sediments were capped with a layer of sediment from a minimally contaminated area. Mussels (Mytilus edulis complex) in the vicinity of the creosote plant were collected before, during, and after the initial remediation process, for monitoring body burdens of PAHs as well as cellular effects indicative of biological damage. Mussels from this area have previously been shown to exhibit an elevated body burden of high molecular weight PAHs, as well as substantial changes in subcellular structures and functions, characteristic of mussels from chemically contaminated environments. Following capping, the body burden of high molecular weight PAHs was substantially reduced early in the restoration process yet mussel contaminant body burdens were approaching pre-cap levels one year after the end of the remediation project. Changes in mussel health were assessed by measuring selected aspects of lysosomal function as well as levels of enzymes and anti-oxidants involved in detoxifying organic chemical contaminants. Substantial improvement throughout capping occurred in lysosomal stability and cytochrome P450 reductase activity in digestive gland, and anti-oxidant status in gill tissue when compared to initial findings. In contrast, increased levels of neutral lipid and lipofuscin in digestive glands indicated that mussels were still suffering biological impairment as a result of chemical contaminant exposure. Overall, indigenous mussels near the marine remediation project showed temporary improvement in tissue body burden of chemical contaminants and some decrease in biological effects.

  7. Ecological aspects of environmental assessment of contaminated areas

    SciTech Connect

    Templeton, W.L.

    1990-04-01

    When large landscapes are contaminated by radionuclides released from nuclear activities, physical processes, such as atmospheric and hydrological transport may move the radioactive materials over large distances resulting in direct external exposure of man and organisms. This paper provides an overview of the modeling of radionuclide movement through defined ecological pathways, describes some ecological problems at remediated sites, and briefly reviews effects of environmental radiation on terrestrial and aquatic biota. This paper describes pathways that should be considered when conducting environmental dose assessments for radionuclides released to the environment. 4 refs.

  8. Plant sentinels and molecular probes that monitor environmental munitions contaminants

    SciTech Connect

    Jackson, P.J.; DeWitt, J.G.; Hill, K.K.; Kuske, C.R.; Kim, D.Y.

    1994-08-01

    Plants accumulate TNT and similar compounds from soil. Their sessile nature requires that plants adapt to environmental changes by biochemical and molecular means. In principle, it is possible to develop a monitoring capability based on expression of any gene that is activated by specific environmental conditions. The authors have identified plant genes activated upon exposure to TNT. Partial gene sequences allow design of DNA probes that measure TNT-induced gene activity. These will be used to develop sensitive assays that monitor gene expression in plants growing in environments possibly contaminated with explosives.

  9. Effect of environmental contaminants on nasal lysozyme secretions.

    PubMed

    Noble, Rudolf E

    2002-02-01

    Human nasal secretions are comprised of lysozyme and albumin as their main protein components. Lysozyme, an anti-microbial substance, is produced by nasal serous cells while albumin is obtained, primarily, from increased nasal vasculature permeability. We measured lysozyme levels in nasal secretions following challenge by a variety of non-infectious environmental contaminants. The methodology given presents a simple and rapid method of collecting nasal secretions and determining their lysozyme content, a technique which can be used for a host of environmental irritants. PMID:11846170

  10. Microlith Based Sorber for Removal of Environmental Contaminants

    NASA Technical Reports Server (NTRS)

    Roychoudhury, S.; Perry, J.

    2004-01-01

    The development of energy efficient, lightweight sorption systems for removal of environmental contaminants in space flight applications is an area of continuing interest to NASA. The current CO2 removal system on the International Space Station employs two pellet bed canisters of 5A molecular sieve that alternate between regeneration and sorption. A separate disposable charcoal bed removes trace contaminants. An alternative technology has been demonstrated using a sorption bed consisting of metal meshes coated with a sorbent, trademarked and patented as Microlith by Precision Combustion, Inc. (PCI); thesemeshes have the potential for direct electrical heating for this application. This allows the bed to be regenerable via resistive heating and offers the potential for shorter regeneration times, reduced power requirement, and net energy savings vs. conventional systems. The capability of removing both CO2 and trace contaminants within the same bed has also been demonstrated. Thus, the need for a separate trace contaminant unit is eliminated resulting in an opportunity for significant weight savings. Unlike the charcoal bed, zeolites for trace contaminant removal are amenable to periodic regeneration. This paper describes the design and performance of a prototype sorber device for simultaneous CO2 and trace contarninant removal and its attendant weight and energy savings.

  11. Observations on environmental contamination in a microbiological laboratory.

    PubMed Central

    Harvey, R. W.; Price, T. H.; Joynson, D. H.

    1976-01-01

    Contamination of a laboratory environment with pathogenic or non-pathogenic micro-organisms may be relevant to safety of technicians and quality of technical performance. Two widely separated incidents in 1968 and 1974 initiated a study of aspects of the laboratory environment. Water-baths, water of syneresis and portions of salmonella cultures spurting out of the sterilizing flame were examined. The water of water-baths was shown to be contaminated from the fluid cultures incubated in them. This raised questions of potential cross-contamination and reporting of false positives. Water of syneresis was sometimes contaminated with salmonellas. A few quantitative counts were made. The range of counts varied between 16 salmonellas per ml. and 13,000,000 salmonellas per ml. Five hundred portions of salmonella cultures and 571 portions of Shigella sonnei cultures which had spurted from the sterilizing flame were examined. All these samples failed to grow salmonellas or shigellas. Precautions necessary to avoid environmental contamination are briefly discussed. PMID:1107415

  12. Potential for portal detection of human chemical and biological contamination

    NASA Astrophysics Data System (ADS)

    Settles, Gary S.; McGann, William J.

    2001-08-01

    The walk-through metal-detection portal is a paradigm of non-intrusive passenger screening in aviation security. Modern explosive detection portals based on this paradigm will soon appear in airports. This paper suggests that the airborne trace detection technology developed for that purpose can also be adapted to human chemical and biological contamination. The waste heat of the human body produces a rising warm-air sheath of 50-80 liters/sec known as the human thermal plume. Contained within this plume are hundreds of bioeffluents from perspiration and breath, and millions of skin flakes. Since early medicine, the airborne human scent was used in the diagnosis of disease. Recent examples also include toxicity and substance abuse, but this approach has never been quantified. The appearance of new bioeffluents or subtle changes in the steady-state may signal the onset of a chemical/biological attack. Portal sampling of the human thermal plume is suggested, followed by a pre-concentration step and the detection of the attacking agent or the early human response. The ability to detect nanogram levels of explosive trace contamination this way was already demonstrated. Key advantages of the portal approach are its rapidity and non-intrusiveness, and the advantage that it does not require the traditional bodily fluid or tissue sampling.

  13. Environmental contaminants, fertility, and multioocytic follicles: a lesson from wildlife?

    PubMed

    Guillette, Louis J; Moore, Brandon C

    2006-07-01

    The overall contribution of environmental exposures to infertility is unknown, but a growing scientific database suggests that exposure to various environmental factors, both in utero and neonatally, could dramatically affect adult fertility. Studies of various contaminant-exposed wildlife populations suggest that multiple mechanisms contribute to changes in gonadal development, maturation of germ cells, fertilization, and pregnancy; specifically, the endocrine processes supporting these events. Although great debate and extensive research has occurred during the last decade surrounding fertility, fecundity, and semen quality, much less work has focused on environmental alterations in oocyte development and maturation. Exposure of the developing ovary to estrogens, whether of pharmaceutical (e.g., diethylstilbesterol) or environmental (e.g., phytoestrogens, pesticides with estrogenic action) origin, can disrupt early oogenesis and folliculogenesis leading to a pathology termed the multioocytic follicle (polyovular follicle), which in rodents reduces fertilization and embryonic survival rates. The mechanism underlying this pathology is hypothesized to involve a disruption in the gonadotropin-estrogen-inhibin/activin signaling pathway. Given the conserved nature of vertebrate oogenesis and folliculogenesis, we suggest that perturbations of these phenomena in humans, caused by environmental contaminant exposure, could lead to altered fertility, as has been reported in wildlife and laboratory rodent models. PMID:16804811

  14. Assessment of myelotoxicity caused by environmental chemicals.

    PubMed Central

    Boorman, G A; Luster, M I; Dean, J H; Campbell, M L

    1982-01-01

    Potential antineoplastic agents must be screened for the delayed toxicity that occurs in many cases of drug-induced bone marrow aplasia. In vitro clonal assays for hematopoietic progenitor cells have been developed to assess the degree of myelotoxicity. This adverse side effect is often the limiting factor in the development of new cancer chemotherapeutics. In addition, many environmental chemicals are cytotoxic to rapidly proliferating cells, but a systematic assessment of their myelotoxicity has not been performed. We have used clonal marrow assays to investigate a panel of chemicals including 2,3,7,8-tetrachlorodibenzo-p-dioxin, polybrominated biphenyls, diethylstilbestrol, benzo(a)pyrene and indomethacin. All were immunotoxic, some to pleuripotent hemopoetic stem cells and other to granulocyte-macrophage progenitors, and at concentrations below those causing other toxic manifestations. This shows that these bone marrow clonal assays, and hopefully future one for erythroid, B- and T-lymphocytes, and megakaryocytes, will provide the specificity and sensitivity necessary to delineate the myelotoxicity of a broad spectrum of environmental chemicals. PMID:6277616

  15. Influences of Environmental Chemicals on Atopic Dermatitis

    PubMed Central

    2015-01-01

    Atopic dermatitis is a chronic inflammatory skin condition including severe pruritus, xerosis, visible eczematous skin lesions that mainly begin early in life. Atopic dermatitis exerts a profound impact on the quality of life of patients and their families. The estimated lifetime prevalence of atopic dermatitis has increased 2~3 fold during over the past 30 years, especially in urban areas in industrialized countries, emphasizing the importance of life-style and environment in the pathogenesis of atopic diseases. While the interplay of individual genetic predisposition and environmental factors contribute to the development of atopic dermatitis, the recent increase in the prevalence of atopic dermatitis might be attributed to increased exposure to various environmental factors rather than alterations in human genome. In recent decades, there has been an increasing exposure to chemicals from a variety of sources. In this study, the effects of various environmental chemicals we face in everyday life - air pollutants, contact allergens and skin irritants, ingredients in cosmetics and personal care products, and food additives - on the prevalence and severity of atopic dermatitis are reviewed. PMID:26191377

  16. Environmental contaminant concentrations in biota from the lower Savannah River, Georgia and South Carolina

    USGS Publications Warehouse

    Winger, P.V.; Schultz, D.P.; Johnson, W.W.

    1990-01-01

    Planned harbor expansion and industrial developments may adversely affect the economically important aquatic resources of the lower Savannah River, including those at the Savannah National Wildlife Refuge. To establish the present level of chemical contamination in this system, we collected a total of 102 samples of nine species of fish and fiddler crabs (Uca pugilator) from eleven sites in the lower Savannah River and on the Savannah National Wildlife Refuge, and analyzed them for concentrations of organochlorine chemicals, aliphatic and aromatic petroleum hydrocarbons, and 13 elemental contaminants: aluminum, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, selenium, and zinc. Residues of DDT (mainly as DDE),trans-nonachlor, dieldrin, Aroclor? 1260, mirex, and petroleum hydrocarbons were common in fish from the lower Savannah River, but concentrations were below those warranting environmental concern. In general, the concentrations of elemental contaminants also were low; however, arsenic, cadmium, and chromium concentrations were elevated in fish from river stations near the city of Savannah, and lead was elevated in samples from the National Wildlife Refuge. Contamination of the lower Savannah River by organic and elemental contaminants, as indicated by concentrations in fishes and fiddler crabs, did not appear to pose a hazard.

  17. 40 CFR 141.11 - Maximum contaminant levels for inorganic chemicals.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Maximum contaminant levels for... (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Maximum Contaminant Levels § 141.11 Maximum contaminant levels for inorganic chemicals. (a) The maximum contaminant level...

  18. Rapid assessment of chemical contamination and toxicity equivalents at a hazardous waste site

    SciTech Connect

    Mashburn, W.E.; Johnson, K.A.; Weisskopf, C.P.; Dickerson, R.L.

    1994-12-31

    Utilizing a new monitoring technique, contaminant burdens are assessed at a hazardous waste site containing polychlorinated biphenyls (PCBs). This approach utilizes a sampling technique which allows for chemical characterization without the costly and time consuming collection and transportation of large samples from the field to the laboratory. In addition, this approach will allow for determination of toxicity equivalents without the use of living organisms. Soil extracts are obtained from a passive sampling device (PSD) constructed of a polymeric membrane containing C{sub 18} sorbent which measures the bioavailable chemical contaminants. The PSDs are deployed in the soil, retrieved from the field and then eluted in the laboratory. The extracts are used for quantitation and determination of chemical identity, concentration, and biological significance. An enzyme induction assay is used to assess toxicity equivalents of the environmental samples. The H411E rat hepatoma cell line was dosed with differing concentrations of PCB Aroclor 1254 to establish a dose-response relationship based on the induction of CytochromeP-450 by measuring the EROD/PROD activity. The cells were then dosed with serial dilutions of PSD extracts to determine toxicity equivalents. A correlation between contaminant concentration and enzyme induction was found with the extracts.

  19. Environmental contaminants of emerging concern in seafood--European database on contaminant levels.

    PubMed

    Vandermeersch, Griet; Lourenço, Helena Maria; Alvarez-Muñoz, Diana; Cunha, Sara; Diogène, Jorge; Cano-Sancho, German; Sloth, Jens J; Kwadijk, Christiaan; Barcelo, Damia; Allegaert, Wim; Bekaert, Karen; Fernandes, José Oliveira; Marques, Antonio; Robbens, Johan

    2015-11-01

    Marine pollution gives rise to concern not only about the environment itself but also about the impact on food safety and consequently on public health. European authorities and consumers have therefore become increasingly worried about the transfer of contaminants from the marine environment to seafood. So-called "contaminants of emerging concern" are chemical substances for which no maximum levels have been laid down in EU legislation, or substances for which maximum levels have been provided but which require revision. Adequate information on their presence in seafood is often lacking and thus potential risks cannot be excluded. Assessment of food safety issues related to these contaminants has thus become urgent and imperative. A database (www.ecsafeseafooddbase.eu), containing available information on the levels of contaminants of emerging concern in seafood and providing the most recent data to scientists and regulatory authorities, was developed. The present paper reviews a selection of contaminants of emerging concern in seafood including toxic elements, endocrine disruptors, brominated flame retardants, pharmaceuticals and personal care products, polycyclic aromatic hydrocarbons and derivatives, microplastics and marine toxins. Current status on the knowledge of human exposure, toxicity and legislation are briefly presented and the outcome from scientific publications reporting on the levels of these compounds in seafood is presented and discussed. PMID:26123540

  20. Characterization of complex mineral assemblages: Implications for contaminant transport and environmental remediation

    PubMed Central

    Bertsch, Paul M.; Seaman, John C.

    1999-01-01

    Surface reactive phases of soils and aquifers, comprised of phyllosilicate and metal oxohydroxide minerals along with humic substances, play a critical role in the regulation of contaminant fate and transport. Much of our knowledge concerning contaminant-mineral interactions at the molecular level, however, is derived from extensive experimentation on model mineral systems. Although these investigations have provided a foundation for understanding reactive surface functional groups on individual mineral phases, the information cannot be readily extrapolated to complex mineral assemblages in natural systems. Recent studies have elucidated the role of less abundant mineral and organic substrates as important surface chemical modifiers and have demonstrated complex coupling of reactivity between permanent-charge phyllosilicates and variable-charge Fe-oxohydroxide phases. Surface chemical modifiers were observed to control colloid generation and transport processes in surface and subsurface environments as well as the transport of solutes and ionic tracers. The surface charging mechanisms operative in the complex mineral assemblages cannot be predicted based on bulk mineralogy or by considering surface reactivity of less abundant mineral phases based on results from model systems. The fragile nature of mineral assemblages isolated from natural systems requires novel techniques and experimental approaches for investigating their surface chemistry and reactivity free of artifacts. A complete understanding of the surface chemistry of complex mineral assemblages is prerequisite to accurately assessing environmental and human health risks of contaminants or in designing environmentally sound, cost-effective chemical and biological remediation strategies. PMID:10097043

  1. Balancing the risks of habitat alteration and environmental contamination in a contaminated forested wetland

    SciTech Connect

    Bleiler, J.A.; Daukas, G.; Richardson, N.

    1994-12-31

    The North Lawrence Oil Dump Site (NLODS) is an inactive hazardous waste site located adjacent to an extensive palustrine forested wetland in upstate New York. Waste oil and oil sludge were disposed of in a lagoon adjacent to the wetland during the 1960s. During periods of high water, oils escaped from the lagoon and were transported into the wetlands. High concentrations of lead and PCBs were detected in NLODS wetland sediments, and contaminants from the site were present in wetland`s plant and animal tissues. However, contaminated portions of the wetlands appear to be physically undisturbed and provide high quality wildlife habitat. The results of an ecological risk assessment indicated that lead and PCB contamination in NLODS sediment may be impacting some components of the wetlands community. The risk management process considered both the toxicological risks associated with lead and PCB contamination, as well as the significant habitat destruction risks associated with remediation. Six potential PCB target cleanup levels were evaluated. Following removal of sediments with PCB contamination greater than 0.5 mg/kg, 3.5 acres of sediment with lead contamination in excess of 250 mg/kg (the New York State ``Severe Effect Level``) would remain. More than 1.5 of these acres would contain lead concentrations in excess of 1,000 mg/kg. Reducing lead levels to background concentrations would require more than 50 acres of wetlands alteration. The Record of Decision at the NLODS recognized the high quality habitat provided by the site`s wetlands, and attempted to balance the risks from habitat alteration with the risks of environmental contamination.

  2. Identifying environmental chemicals causing mutations and cancer.

    PubMed

    Ames, B N

    1979-05-11

    Damage to DNA appears to be the major cause of most cancer and genetic birth defects and may contribute to aging and heart disease as well. The agents that cause this damage must be identified. Many of these agents are natural chemicals present in the human diet as complex mixtures. The tens of thousands of man-made chemicals that have been introduced into the environment in the last few decades must also be tested for their ability to damage DNA. Existing animal tests and human epidemiology alone are inadequate for this task because of time, expense, and the difficulty of dealing with complex mixtures, Newly developed short-term tests, most of them assaying for mutagenicity, are discussed as key tools in identifying environmental mutagens and carcinogens. PMID:373122

  3. A signal processing framework for simultaneous detection of multiple environmental contaminants

    NASA Astrophysics Data System (ADS)

    Chakraborty, Subhadeep; Manahan, Michael P.; Mench, Matthew M.

    2013-11-01

    The possibility of large-scale attacks using chemical warfare agents (CWAs) has exposed the critical need for fundamental research enabling the reliable, unambiguous and early detection of trace CWAs and toxic industrial chemicals. This paper presents a unique approach for the identification and classification of simultaneously present multiple environmental contaminants by perturbing an electrochemical (EC) sensor with an oscillating potential for the extraction of statistically rich information from the current response. The dynamic response, being a function of the degree and mechanism of contamination, is then processed with a symbolic dynamic filter for the extraction of representative patterns, which are then classified using a trained neural network. The approach presented in this paper promises to extend the sensing power and sensitivity of these EC sensors by augmenting and complementing sensor technology with state-of-the-art embedded real-time signal processing capabilities.

  4. Global warming and environmental contaminants in aquatic organisms: the need of the etho-toxicology approach.

    PubMed

    Manciocco, Arianna; Calamandrei, Gemma; Alleva, Enrico

    2014-04-01

    Environmental contaminants are associated with a wide spectrum of pathological effects. Temperature increase affects ambient distribution and toxicity of these chemicals in the water environment, representing a potentially emerging problem for aquatic species with short-, medium- and long-term repercussions on human health through the food chain. We assessed peer-reviewed literature, including primary studies, review articles and organizational reports available. We focused on studies concerning toxicity of environmental pollutants within a global warming scenario. Existing knowledge on the effects that the increase of water temperature in a contaminated situation has on physiological mechanisms of aquatic organisms is presented. Altogether we consider the potential consequences for the human beings due to fish and shellfish consumption. Finally, we propose an etho-toxicological approach to study the effects of toxicants in conditions of thermal increase, using aquatic organisms as experimental models under laboratory controlled conditions. PMID:24480426

  5. Environmental surface cleanliness and the potential for contamination during handwashing.

    PubMed

    Griffith, Christopher J; Malik, Rifhat; Cooper, Rose A; Looker, Nick; Michaels, Barry

    2003-04-01

    Effective handwashing (including drying) is important in infection control. The ability of the various stages of handwashing to decrease skin-surface microbial counts has been documented. However, an important element, environmental surface cleanliness, and the potential for contamination of hands during the process has not been well studied or quantified. An examination of the adenosine triphosphate (a measure of residual organic soil), bacterial, and staphylococcal load on ward handwash station surfaces, which could be touched during handwashing, is reported. Hand contact surfaces tested consisted of approximately 620 each of: faucet handles, soap dispenser activator mechanisms, and folded paper-towel dispenser exits. Failure rates in excess of benchmark clean values were higher with adenosine triphosphate assays than microbial counts. This could indicate the presence of a higher level of general organic debris (eg, skin cells) as opposed to microbial contamination or could reflect greater assay sensitivity. Faucet handles were more likely to be contaminated and be in excess of benchmark values than paper-towel dispenser exits. However, the latter are likely to be the final surface touched during the handwashing process and overall nearly 20% were above microbiologic benchmark values. Many of the organisms isolated were staphylococci and the results are discussed within the context of microbial cross-contamination and potential pathogen spread. PMID:12665742

  6. Residual metallic contamination of transferred chemical vapor deposited graphene.

    PubMed

    Lupina, Grzegorz; Kitzmann, Julia; Costina, Ioan; Lukosius, Mindaugas; Wenger, Christian; Wolff, Andre; Vaziri, Sam; stling, Mikael; Pasternak, Iwona; Krajewska, Aleksandra; Strupinski, Wlodek; Kataria, Satender; Gahoi, Amit; Lemme, Max C; Ruhl, Guenther; Zoth, Guenther; Luxenhofer, Oliver; Mehr, Wolfgang

    2015-05-26

    Integration of graphene with Si microelectronics is very appealing by offering a potentially broad range of new functionalities. New materials to be integrated with the Si platform must conform to stringent purity standards. Here, we investigate graphene layers grown on copper foils by chemical vapor deposition and transferred to silicon wafers by wet etching and electrochemical delamination methods with respect to residual submonolayer metallic contaminations. Regardless of the transfer method and associated cleaning scheme, time-of-flight secondary ion mass spectrometry and total reflection X-ray fluorescence measurements indicate that the graphene sheets are contaminated with residual metals (copper, iron) with a concentration exceeding 10(13) atoms/cm(2). These metal impurities appear to be partially mobile upon thermal treatment, as shown by depth profiling and reduction of the minority charge carrier diffusion length in the silicon substrate. As residual metallic impurities can significantly alter electronic and electrochemical properties of graphene and can severely impede the process of integration with silicon microelectronics, these results reveal that further progress in synthesis, handling, and cleaning of graphene is required to advance electronic and optoelectronic applications. PMID:25853630

  7. Chemical contamination and transformation of soils in hydrocarbon production regions

    NASA Astrophysics Data System (ADS)

    Zamotaev, I. V.; Ivanov, I. V.; Mikheev, P. V.; Nikonova, A. N.

    2015-12-01

    The current concepts of soil pollution and transformation in the regions of hydrocarbon production have been reviewed. The development of an oil field creates extreme conditions for pedogenesis. Tendencies in the radial migration, spatial distribution, metabolism, and accumulation of pollutants (oil, oil products, and attendant heavy metals) in soils of different bioclimatic zones have been analyzed. The radial and lateral mobility of pollution halos is a universal tendency in the technogenic transformation of soils and soil cover in the regions of hydrocarbon production. The biodegradation time of different hydrocarbon compounds strongly varies under different landscape conditions, from several months to several tens of years. The transformation of original (mineral and organic) soils to their technogenic modifications (mechanically disturbed, chemically contaminated, and chemo soils and chemozems) occurs in the impact zone of technogenic hydrocarbon fluxes under any physiographical conditions. The integrated use of the existing methods for the determination of the total content and qualitative composition of bituminous substances and polyaromatic hydrocarbons in combination with the chromatographic determination of normal alkanes and hydrocarbon gases, as well as innovative methods of studies, allows revealing new processes and genetic relationships in soils and studying the functioning of soils and soil cover. The study of the hydrocarbon contamination of soils is important for development of restoration measures and lays the groundwork for the ecological and hygienic regulation based on the zonation of soil and landscape resistance to different pollutants.

  8. Prenatal risks deriving from environmental chemicals.

    PubMed

    Mantovani, A; Ricciardi, C; Macr, C; Stazi, A V

    1993-01-01

    Hundreds of environmental chemicals affect prenatal development in experimental animals. However, only methylmercury and PCBs have been connected with such effects in humans during localized outbreaks of high exposure. In addition growth and development might also be affected by long-term intake of lead, fluorides or PCBs. Several factors may explain the discrepancy between human and animal data: the actual exposure of the population is below threshold levels, unspecific or delayed effects can be difficult to identify, etc. When experimental data are used to assess the hazards for the conceptus, due consideration should be given to actual ability of the study to detect effects. Thus, the limitations in statistical power, the relevance of the parameters considered and low-dose extrapolation should be taken into account. Finally, understanding toxicokinetics and biological mechanisms is needed to perform interspecies comparisons. Three examples of environmental chemicals showing different prenatal hazards are presented: thiabendazole, a benzimidazole compound with a moderate teratogenic potential, but which could represent a good model for biological extrapolation; nitrofen, a diphenyl ether herbicide which may pose a significant hazard, because of its high potential, toxicokinetics, and specific, hormone-like, teratogenic mechanisms; PCBs, well-known, global, cumulative pollutants which are not teratogenic in the laboratory animals, but may affect the human conceptus at high intake levels. PMID:8129272

  9. Deriving uncertainty factors for threshold chemical contaminants in drinking water.

    PubMed

    Ritter, Leonard; Totman, Céline; Krishnan, Kannan; Carrier, Richard; Vézina, Anne; Morisset, Véronique

    2007-10-01

    Uncertainty factors are used in the development of drinking-water guidelines to account for uncertainties in the database, including extrapolations of toxicity from animal studies and variability within humans, which result in some uncertainty about risk. The application of uncertainty factors is entrenched in toxicological risk assessment worldwide, but is not applied consistently. This report, prepared in collaboration with Health Canada, provides an assessment of the derivation of the uncertainty factor assumptions used in developing drinking-water quality guidelines for chemical contaminants. Assumptions used by Health Canada in the development of guidelines were compared to several other major regulatory jurisdictions. This assessment has revealed that uncertainty factor assumptions have been substantially influenced by historical practice. While the application of specific uncertainty factors appears to be well entrenched in regulatory practice, a well-documented and disciplined basis for the selection of these factors was not apparent in any of the literature supporting the default assumptions of Canada, the United States, Australia, or the World Health Organization. While there is a basic scheme used in most cases in developing drinking-water quality guidelines for nonthreshold contaminants by the jurisdictions included in this report, additional factors are sometimes included to account for other areas of uncertainty. These factors may include extrapolating subchronic data to anticipated chronic exposure, or use of a LOAEL instead of a NOAEL. The default value attributed to each uncertainty factor is generally a factor of 3 or 10; however, again, no comprehensive guidance to develop and apply these additional uncertainty factors was evident from the literature reviewed. A decision tree has been developed to provide guidance for selection of appropriate uncertainty factors, to account for the range of uncertainty encountered in the risk assessment process. Recent development of a series of "decision trees" by WHO to derive chemical specific adjustment factors for inter- and intraspecies variability may present an opportunity for a more systematic approach for the identification of evidence-based uncertainty factors. PMID:17934949

  10. Effects of environmental contaminants on reptiles: A review

    USGS Publications Warehouse

    Hall, R.J.

    1980-01-01

    The literature relating to the effects of environmental contaminants on reptiles is reviewed and certain generalizations based on studies of other kinds of vertebrates are presented. Reports of reptilian mortality from pesticide applications are numerous enough to establish the sensitivity of reptiles to these materials. Reports of residue analyses demonstrate the ability of reptiles to accumulate various contaminants. but the significance of the residues to reptilian populations is unknown. A few authors have reported the distribution of residues in reptilian tissues; others have investigated uptake or loss rates. Physiological studies have shown that organochlorines may inhibit enzymes involved in active transport and have correlated the activity of potential detoxifying enzymes with residue levels. There is some suggestion that pesticide residues may interfere with reproduction in oviparous snakes. Needs for future research are discussed.

  11. Noble metals: a toxicological appraisal of potential new environmental contaminants.

    PubMed Central

    Brubaker, P E; Moran, J P; Bridbord, K; Hueter, F G

    1975-01-01

    The public health benefits expected by reducing known hazardous emissions from mobile sources should not be compromised by increasing levels of other potentially hazardous unregulated emissions. Catalytic converters are going to be used to meet the statutory requirements on carbon monoxide and hydrocarbon emissions from light duty motor vehicles. Platinum and palladium metals are the catalytic materials to be used in these emission control devices. Preliminary experimental evidence and analysis of the impact of these control devices on the future use and demand for platinum indicates that this metal may appear at detectable levels in the environment by the end of this decade. At the present time, platinum and palladium are not present in the public environment and represent potentially new environmental contaminants as a consequence of use of this new abatement control technology. There is relatively little information available to adequately assess the potential health hazards that may be associated with exposure to these metals and their compounds. Analysis of the environmental problems and concerns associated with possible new environmental contaminants are discussed. Limited estimates are made on community exposure by use of a meteorological dispersion model. Biodegradation potential and attention is also given to the limited toxicological information available. PMID:50939

  12. Investigation of the Use of "Cucumis Sativus" for Remediation of Chromium from Contaminated Environmental Matrices: An Interdisciplinary Instrumental Analysis Project

    ERIC Educational Resources Information Center

    Butler, Lynsey R.; Edwards, Michael R.; Farmer, Russell; Greenly, Kathryn J.; Hensler, Sherri; Jenkins, Scott E.; Joyce, J. Michael; Mann, Jason A.; Prentice, Boone M.; Puckette, Andrew E.; Shuford, Christopher M.; Porter, Sarah E. G.; Rhoten, Melissa C.

    2009-01-01

    An interdisciplinary, semester-long project is presented in which students grow Cucumis sativus (cucumber) plants from seeds and study the ability of the plants to remediate a heavy metal from contaminated soil or water or both. Phytoremediation strategies for environmental cleanup are presented as possible alternatives to chemical based clean-up

  13. Investigation of the Use of "Cucumis Sativus" for Remediation of Chromium from Contaminated Environmental Matrices: An Interdisciplinary Instrumental Analysis Project

    ERIC Educational Resources Information Center

    Butler, Lynsey R.; Edwards, Michael R.; Farmer, Russell; Greenly, Kathryn J.; Hensler, Sherri; Jenkins, Scott E.; Joyce, J. Michael; Mann, Jason A.; Prentice, Boone M.; Puckette, Andrew E.; Shuford, Christopher M.; Porter, Sarah E. G.; Rhoten, Melissa C.

    2009-01-01

    An interdisciplinary, semester-long project is presented in which students grow Cucumis sativus (cucumber) plants from seeds and study the ability of the plants to remediate a heavy metal from contaminated soil or water or both. Phytoremediation strategies for environmental cleanup are presented as possible alternatives to chemical based clean-up…

  14. Chemical mixtures and environmental effects: a pilot study to assess ecological exposure and effects in streams

    USGS Publications Warehouse

    Buxton, Herbert T.; Reilly, Timothy J.; Kuivila, Kathryn M.; Kolpin, Dana W.; Bradley, Paul M.; Villeneuve, Daniel L.; Mills, Marc A.

    2015-01-01

    Assessment and management of the risks of exposure to complex chemical mixtures in streams are priorities for human and environmental health organizations around the world. The current lack of information on the composition and variability of environmental mixtures and a limited understanding of their combined effects are fundamental obstacles to timely identification and prevention of adverse human and ecological effects of exposure. This report describes the design of a field-based study of the composition and biological activity of chemical mixtures in U.S. stream waters affected by a wide range of human activities and contaminant sources. The study is a collaborative effort by the U.S. Geological Survey and the U.S. Environmental Protection Agency. Scientists sampled 38 streams spanning 24 States and Puerto Rico. Thirty-four of the sites were located in watersheds impacted by multiple contaminant sources, including industrial and municipal wastewater discharges, crop and animal agricultural runoff, urban runoff, and other point and nonpoint contaminant sources. The remaining four sites were minimally development reference watersheds. All samples underwent comprehensive chemical and biological characterization, including sensitive and specific direct analysis for over 700 dissolved organic and inorganic chemicals and field parameters, identification of unknown contaminants (environmental diagnostics), and a variety of bioassays to evaluate biological activity and toxicity.

  15. Chemical and Flowfield Modeling for Enhanced Analysis of Contamination Experiments

    NASA Technical Reports Server (NTRS)

    Braunstein, Matthew; Finchum, Andy (Technical Monitor)

    2001-01-01

    This paper describes the application of a new Direct Simulation Monte Carlo (DSMC) code, the Molecular Beam Simulator (MBS), which is designed to analyze laboratory scale molecular beam-surface (and crossed-beam) experiments. The MBS is primarily intended to model experiments associated with spacecraft contamination effects, but it can also be used to simulate a variety of surface chemistry and reactive flow measurements. The MBS code is fully three-dimensional, includes a wide-range of chemical processes, and can model one or multiple pulsed (non-steady) sources. As an example application of the MBS code, a fast, pulsed, oxygen atom-surface experiment which examines the chemistry behind erosion of graphite by oxygen atoms is analyzed. Unsteady DSMC simulations show that experimental observations of excited molecular states after the pulse has hit the surface are consistent with two distinct chemical mechanisms: a direct one where the excited molecules are formed on the surface, and a two-step mechanism where ground state molecules formed on the surface are collisionally excited after they leave the surface by trailing oxygen atoms in the pulse. Further DSMC calculations suggest experiments which can distinguish between these mechanisms.

  16. Human health hazards associated with chemical contamination of aquatic environment.

    PubMed Central

    Stara, J F; Kello, D; Durkin, P

    1980-01-01

    Given the finite supply of water available for human use, continued chemical contamination of the aquatic environment may pose a significant human health hazard. Consequently, an effort must be made to develop ambient water quality criteria to protect human health and preserve the integrity of the aquatic environment. In developing water quality criteria based on human health effects, information on sources of exposure, pharmacokinetics, and adverse effects must be carefully evaluated. Information on sources of exposure is needed to determine the contribution of exposure from water relative to all other sources. Pharmacokinetic data are used in inter- and intraspecies extrapolation and in characterizing the mode of toxic action. Information on toxic effects includes data on acute, subchronic, and chronic toxicity, mutagenicity, teratogenicity, and carcinogenicity. In analyzing such information, a distinction is made between threshold and nonthreshold effects. Currently, carcinogenicity and mutagenicity are considered to be nonthreshold effects. For carcinogens and mutagens, criteria are calculated by postulating an "acceptable" increased level of risk and using extrapolation models to estimate the dose which would result in this increased level of risk. For other chemicals, thresholds are assumed and criteria are calculated by deriving "acceptable daily intakes" for man which would presumably result in no observable adverse effects. Neither process is exact, and attempts must be made to improve and verify risk assessment methodologies. PMID:6993199

  17. Developing methods to assess and predict the population level effects of environmental contaminants.

    USGS Publications Warehouse

    Emlen, J.M.; Springman, K.R.

    2007-01-01

    The field of ecological toxicity seems largely to have drifted away from what its title implies--assessing and predicting the ecological consequences of environmental contaminants--moving instead toward an emphasis on individual effects and physiologic case studies. This paper elucidates how a relatively new ecological methodology, interaction assessment (INTASS), could be useful in addressing the field's initial goals. Specifically, INTASS is a model platform and methodology, applicable across a broad array of taxa and habitat types, that can be used to construct population dynamics models from field data. Information on environmental contaminants and multiple stressors can be incorporated into these models in a form that bypasses the problems inherent in assessing uptake, chemical interactions in the environment, and synergistic effects in the organism. INTASS can, therefore, be used to evaluate the effects of contaminants and other stressors at the population level and to predict how changes in stressor levels or composition of contaminant mixtures, as well as various mitigation measures, might affect population dynamics.

  18. Secondary environmental impacts of remedial alternatives for sediment contaminated with hydrophobic organic contaminants.

    PubMed

    Choi, Yongju; Thompson, Jay M; Lin, Diana; Cho, Yeo-Myoung; Ismail, Niveen S; Hsieh, Ching-Hong; Luthy, Richard G

    2016-03-01

    This study evaluates secondary environmental impacts of various remedial alternatives for sediment contaminated with hydrophobic organic contaminants using life cycle assessment (LCA). Three alternatives including two conventional methods, dredge-and-fill and capping, and an innovative sediment treatment technique, in-situ activated carbon (AC) amendment, are compared for secondary environmental impacts by a case study for a site at Hunters Point Shipyard, San Francisco, CA. The LCA results show that capping generates substantially smaller impacts than dredge-and-fill and in-situ amendment using coal-based virgin AC. The secondary impacts from in-situ AC amendment can be reduced effectively by using recycled or wood-based virgin AC as production of these materials causes much smaller impacts than coal-based virgin AC. The secondary environmental impacts are highly sensitive to the dredged amount and the distance to a disposal site for dredging, the capping thickness and the distance to the cap materials for capping, and the AC dose for in-situ AC amendment. Based on the analysis, this study identifies strategies to minimize secondary impacts caused by different remediation activities: optimize the dredged amount, the capping thickness, or the AC dose by extensive site assessments, obtain source materials from local sites, and use recycled or bio-based AC. PMID:26590871

  19. Environmental review of options for managing radioactively contaminated carbon steel

    SciTech Connect

    1996-10-01

    The U.S. Department of Energy (DOE) is proposing to develop a strategy for the management of radioactively contaminated carbon steel (RCCS). Currently, most of this material either is placed in special containers and disposed of by shallow land burial in facilities designed for low-level radioactive waste (LLW) or is stored indefinitely pending sufficient funding to support alternative disposition. The growing amount of RCCS with which DOE will have to deal in the foreseeable future, coupled with the continued need to protect the human and natural environment, has led the Department to evaluate other approaches for managing this material. This environmental review (ER) describes the options that could be used for RCCS management and examines the potential environmental consequences of implementing each. Because much of the analysis underlying this document is available from previous studies, wherever possible the ER relies on incorporating the conclusions of those studies as summaries or by reference.

  20. Environmental effects of oilfield chemicals on composite

    SciTech Connect

    Sorem, R.M.

    1998-12-31

    This paper presents a feasibility study of the effects of oilfield chemicals on composite materials. In this initial study only hydrochloric acid is considered. Initial attempts were made to test stressed specimens, but results were very poor. Subsequent testing was performed to determine how the composite material constituents reacted to the hydrochloric acid. The initial testing was performed on tubular specimens with axial and essentially hoop wound fibers of different materials with different resins. The specimens were loaded in bending to induce representative strains in the tubing. All specimens failed. The second tests consisted of only an environmental soak to determine the amount of mass uptake as well as the reduction in strength. The strength reduction results will be presented at a later time. Testing was performed on S-2 glass, carbon and Kevlar 49 as well as three different resins.

  1. Pathway analysis and exposure assessment: MEPAS modeling for nonradiological chemical contaminants at the Hanford Site

    SciTech Connect

    Blanton, M.L.; Dirkes, R.; Buck, J.; Cooper, A.; Castieton, K.; Glantz, C.

    1995-12-31

    A Chemical Pathway Analysis and Exposure Assessment was performed by the Surface Environmental Surveillance Project (SESP). The SESP monitors air, surface water, sediment, agricultural products, vegetation, soil, and wildlife in order to assess onsite of offsite environmental impacts and offsite human health risk at the Hanford Site. The objectives of this study are (1) determine if a nonradiological chemical monitoring program is warranted for the Hanford Site, (2) ensure that the selection of surveillance parameters such as media, sampling location, and analytes are chosen in a manner that is scientifically sound and cost-efficient, and (3) identify specific nonradiological chemicals of concern (COC) for the Hanford Site. The basis for identification of COC for the Hanford Site was an extensive literature review. The model was also used to predict COC concentrations required onsite to achieve an offsite cancer incidence of 1 E-6 and a hazard quotient of 1.0. This study indicated that nonradiological chemical contamination occurring onsite does not pose a significant offsite human health risk. The highest cancer incidence to the offsite maximally exposed individual from COC was from arsenic (1.76E-1 0); the highest hazard quotient was chromium VI (1.48E-04).

  2. Shellfish and residual chemical contaminants: hazards, monitoring, and health risk assessment along French coasts.

    PubMed

    Guéguen, Marielle; Amiard, Jean-Claude; Arnich, Nathalie; Badot, Pierre-Marie; Claisse, Didier; Guérin, Thierry; Vernoux, Jean-Paul

    2011-01-01

    In this review, we address the identification of residual chemical hazards in shellfish collected from the marine environment or in marketed shellfish. Data, assembled on the concentration of contaminants detected, were compared with the appropriate regulatory and food safety standards. Moreover, data on human exposure and body burden levels were evaluated in the context of potential health risks.Shellfish farming is a common industry along European coasts. The primary types of shellfish consumed in France are oysters, mussels, king scallops, winkles,whelks, cockles, clams, and other scallops. Shellfish filter large volumes of water to extract their food and are excellent bioaccumulators. Metals and other pollutants that exist in the marine environment partition into particular organs, according to their individual chemical characteristics. In shellfish, accumulation often occurs in the digestive gland, which plays a role in assimilation, excretion, and detoxification of contaminants. The concentrations of chemical contaminants in bivalve mollusks are known to fluctuate with the seasons.European regulations limit the amount and type of contaminants that can appear in foodstuffs. Current European standards regulate the levels of micro-biological agents, phycotoxins, and some chemical contaminants in food. Since 2006, these regulations have been compiled into the "Hygiene Package." Bivalve mollusks must comply with maximum levels of certain contaminants as follows:lead (1.5 mg kg-1), cadmium (1 mg kg-1), mercury (0.5 mg kg-1), dioxins (4 pg g-1 and dioxins + DL-PCBs 8 pg g-1), and benzo[a]pyrene (10 μp.g kg-1).In this review, we identify the levels of major contaminants that exist in shellfish(collected from the marine environment and/or in marketed shellfish). The follow-ing contaminants are among those that are profiled: Cd, Pb, Hg, As, Ni, Cr, V,Mn, Cu, Zn, Co, Se, Mg, Mo, radionuclides, benzo[a]pyrene, PCBs, dioxins and furans, PAHs, TBT, HCB, dieldrin, DDT, lindane, triazines, PBDE, and chlorinated paraffins.In France, the results of contaminant monitoring have indicated that Cd, but not lead (< 0.26 mg kg-1) or mercury (< 0.003 mg kg-1), has had some non-compliances. Detections for PCBs and dioxins in shellfish were far below the regulatory thresholds in oysters (< 0.6 pg g-l), mussels (< 0.6 pg g-1), and king scallops (< 0.4 pg g-1). The benzo[a]pyrene concentration in marketed mussels and farmed shellfish does not exceed the regulatory threshold. Some monitoring data are available on shellfish flesh contamination for unregulated organic contaminants.Of about 100 existing organo stannic compounds, residues of the mono-, di-, and tributyltin (MBT, DBT, and TBT) and mono-, di-, and triphenyltin (MPT, DPT,and TPT) compounds are the most frequently detected in fishery products. Octyltins are not found in fishery products. Some bivalve mollusks show arsenic levels up to 15.8 mg kg-1. It seems that the levels of arsenic in the environment derive less from bioaccumulation, than from whether the arsenic is in an organic or an inorganic form. In regard to the other metals, levels of zinc and magnesium are higher in oysters than in mussels.To protect shellfish from chemical contamination, programs have been established to monitor water masses along coastal areas. The French monitoring network(ROCCH) focuses on environmental matrices that accumulate contaminants. These include both biota and sediment. Example contaminants were studied in a French coastal lagoon (Arcachon Bay) and in an estuary (Bay of Seine), and these were used to illustrate the usefulness of the monitoring programs. Twenty-one pesticidal and biocidal active substances were detected in the waters of Arcachon Bay during the summers from 1999 to 2003, at concentrations ranging from a few nanograms per liter to several hundred nanograms per liter. Most of the detected substances were herbicides, including some that are now banned. Organotin compounds have been detected in similarly semi-enclosed waters elsewhere (bays, estuaries, and harbors).However, the mean concentrations of cadmium, mercury, lead, and benzo[a]pyrene,in transplanted mussels, were below the regulatory limits.In 2007, the mean daily consumption of shellfish in the general French population was estimated to be 4.5 g in adults; however, a wide variation occurs by region and season (INCA 2 study). Tabulated as a proportion of the diet, shellfish consumption represents only 0.16% of overall solid food intake. However, the INCA 2 survey was not well suited to estimating shellfish consumption because of the small number of shellfish consumers sampled. In contrast, the mean consumption rate of bivalve mollusks among adult high consumers of fish and seafood products, i.e., adults who eat fish or seafood at least twice a week, was estimated to be 153 g week-1 (8 kg yr-1). The highest mean consumption is for king scallops (39 g week-1), followed by oysters (34 g week-1) and mussels (22 g week-1). Thus, for high seafood consumers, the contribution of shellfish to inorganic contaminant levels is 1-10% TWI or PTWI for Cd, MeHg, and Sn (up to 19% for Sn), and the arsenic body burden is higher for 22% of individuals studied.The human health risks associated with consuming chemical contaminants in shellfish are difficult to assess for several reasons: effects may only surface after long-term exposure (chronic risk), exposures may be discontinuous, and contamination may derive from multiple sources (food, air, occupational exposure, etc.).Therefore, it is not possible to attribute a high body burden specifically to shellfish consumption even if seafood is a major dietary contributor of any contaminant, e.g.,arsenic and mercury.The data assembled in this review provide the arguments for maintaining the chemical contaminant monitoring programs for shellfish. Moreover, the results presented herein suggest that monitoring programs should be extended to other chemicals that are suspected of presenting a risk to consumers, as illustrated by the high concentration reported for arsenic (in urine) of high consumers of seafood products from the CALIPSO study. In addition, the research conducted in shellfish-farming areas of Arcachon Bay highlights the need to monitor TBT and PAH contamination levels to ensure that these chemical pollutants do not migrate from the harbor to oyster farms.Finally, we have concluded that shellfish contamination from seawater offers a rather low risk to the general French population, because shellfish do not constitute a major contributor to dietary exposure of chemical contaminants. Notwithstanding,consumer vigilance is necessary among regular shellfish consumers, and especially for those residing in fishing communities, for pregnant and breast-feeding women,and for very young children. PMID:21541848

  3. Chemical Contamination of the Lower Rio Grande near Laredo, TX

    NASA Astrophysics Data System (ADS)

    Flores, B.; Ren, J.; Krishnamurthy, S.; Belzer, W.

    2006-12-01

    The Rio Grande River stretches over 2000 miles from the southern Rocky Mountains in Colorado to the tip of Texas where the Rio Grande meets the Gulf of Mexico. It is the natural boundary between U.S. and Mexico from El Paso, TX, to Brownsville, TX. The communities along the border heavily rely upon the Rio Grande as a primary source of water for consumption, agricultural uses, supporting wildlife and recreation. For many years the Rio Grande has been polluted with municipal, industrial, agricultural and farming contaminants from both sides of the border. This pollution has led to the extinction or reduction of certain wildlife species as well as affecting the health of the residences along the border. Even though great strides have been made in monitoring the Rio Grande, there has been a lack of intense monitoring data collection for pollutants such as pesticides. Three sampling sites including Manadas Creek, the Rio Grande River at International Bridge I, and USGS monitoring site 08459200 off of Highway 83 were chosen. The water quality parameters focused include temperature, pH, conductivity, dissolve oxygen (DO), salinity, total dissolved solids, nutrients, metals and pesticides. Preliminary results have shown elevated concentration of total phosphorus and ortho-phosphorus in the Manadas Creek site. Organochlorinated pesticides such as heptachlor and 4, 4 DDE were detected at various concentrations at all sites and endrin aldehyde was found at Manadas Creek site. This research has provided more information on the current chemical contamination level of the Rio Grande in the Laredo area.

  4. Evaluation of Microbiological and Chemical Contaminants in Poultry Farms

    PubMed Central

    Skóra, Justyna; Matusiak, Katarzyna; Wojewódzki, Piotr; Nowak, Adriana; Sulyok, Michael; Ligocka, Anna; Okrasa, Małgorzata; Hermann, Janusz; Gutarowska, Beata

    2016-01-01

    The aim of the study was to evaluate the microbiological and chemical contamination in settled dust at poultry farms. The scope of research included evaluating the contributions of the various granulometric fractions in settled dust samples, assessing microbial contamination using culture methods, concentrations of secondary metabolites in dust and their cytotoxicity against hepatocyte chicken cells by means of MTT (3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) tests. In addition, we also evaluated the concentration of selected volatile odorous compounds (VOCs) using gas chromatographic and spectrophotometric methods and airborne dust concentration in the air with DustTrak™ DRX Aerosol Monitor. Studies were carried out on chicken broilers and laying hens at 13 poultry farms, with numbers of birds ranging from 8000 to 42,000. The airborne total dust concentration at poultry farms averaged 1.44 mg/m3 with a high percentage of the PM10 fraction (particulate matter with a diameter less than 10 μm). Microorganism concentrations in the settled dust were: 3.2 × 109 cfu/g for bacteria and 1.2 × 106 cfu/g for fungi. Potential pathogens (Enterococcus spp., Escherichia coli, Salmonella spp., Aspergillus fumigatus, Paecilomyces variotii) were also found. Secondary metabolites included aurofusarin, deoxynivalenol, 15-hydroxyculmorin zearalenone, zearalenone-sulfate, infectopyron, and neochinulin A. However, the dust samples showed weak cytotoxicity towards chicken hepatocyte cells, which ranged between 9.2% and 29.7%. Among volatile odorous compounds ammonia, acrolein, methyloamine, acetic acid, acetoaldehyde and formaldehyde were detected in the air. In conclusion, settled dust can be a carrier of microorganisms, odours and secondary metabolites in poultry farms, which can be harmful to workers’ health. PMID:26861361

  5. Cancer mortality among workers in chemical plant contaminated with dioxin.

    PubMed

    Manz, A; Berger, J; Dwyer, J H; Flesch-Janys, D; Nagel, S; Waltsgott, H

    1991-10-19

    Dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD) can arise as a contaminant in the production of herbicides. It causes chloracne in those exposed to it but its human carcinogenicity has been a matter of dispute. We report here a mortality follow-up of 1583 workers (1184 men, 399 women) employed in a chemical plant in Germany that produced herbicides, including processes contaminated with TCDD. Production of TCDD was reduced from 1954 after an outbreak of chloracne. Vital status up to 1989 was determined for 97.1% of workers hired between 1952 and 1984, and 367 deaths (313 men, 54 women) were recorded. A malignant neoplasm was the underlying cause of death in 93 men and 20 women. Standardised mortality ratios (SMR) were calculated with, as references, national mortality statistics for West Germany and deaths in a cohort of male gas workers; for total cancer mortality they were 1.24 (95% confidence interval 1.00-1.52) and 1.39 (1.10-1.75), respectively, among men. Cancer mortality was increased among men with 20 or more years of employment (SMR = 1.87 [Germany] and 1.82 [gas workers]) and among men who began employment before 1955 (SMR = 1.61 and 1.87). The group with suspected highest exposure to TCDD had SMRs of 1.42 and 1.78. Only 7% of cohort women worked in the high exposure locations in the plant, compared with 39.6% of men, and no increased risk of cancer mortality was observed among women; but breast cancer mortality was raised (SRM = 2.15). These results, together with a US occupational study and a German investigation of accidental exposure, support the hypothesis that TCDD is a human carcinogen. PMID:1681339

  6. Evaluation of Microbiological and Chemical Contaminants in Poultry Farms.

    PubMed

    Skóra, Justyna; Matusiak, Katarzyna; Wojewódzki, Piotr; Nowak, Adriana; Sulyok, Michael; Ligocka, Anna; Okrasa, Małgorzata; Hermann, Janusz; Gutarowska, Beata

    2016-01-01

    The aim of the study was to evaluate the microbiological and chemical contamination in settled dust at poultry farms. The scope of research included evaluating the contributions of the various granulometric fractions in settled dust samples, assessing microbial contamination using culture methods, concentrations of secondary metabolites in dust and their cytotoxicity against hepatocyte chicken cells by means of MTT (3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide) tests. In addition, we also evaluated the concentration of selected volatile odorous compounds (VOCs) using gas chromatographic and spectrophotometric methods and airborne dust concentration in the air with DustTrak™ DRX Aerosol Monitor. Studies were carried out on chicken broilers and laying hens at 13 poultry farms, with numbers of birds ranging from 8000 to 42,000. The airborne total dust concentration at poultry farms averaged 1.44 mg/m³ with a high percentage of the PM10 fraction (particulate matter with a diameter less than 10 μm). Microorganism concentrations in the settled dust were: 3.2 × 10⁸ cfu/g for bacteria and 1.2 × 10⁶ cfu/g for fungi. Potential pathogens (Enterococcus spp., Escherichia coli, Salmonella spp., Aspergillus fumigatus, Paecilomyces variotii) were also found. Secondary metabolites included aurofusarin, deoxynivalenol, 15-hydroxyculmorin zearalenone, zearalenone-sulfate, infectopyron, and neochinulin A. However, the dust samples showed weak cytotoxicity towards chicken hepatocyte cells, which ranged between 9.2% and 29.7%. Among volatile odorous compounds ammonia, acrolein, methyloamine, acetic acid, acetoaldehyde and formaldehyde were detected in the air. In conclusion, settled dust can be a carrier of microorganisms, odours and secondary metabolites in poultry farms, which can be harmful to workers' health. PMID:26861361

  7. Environmental toxicity testing of contaminated soil based on microcalorimetry.

    PubMed

    Gruiz, K; Feigl, V; Hajdu, Cs; Tolner, M

    2010-10-01

    Contaminated site assessment and monitoring requires efficient risk-management tools including innovative environmental toxicity tests. The first application of microcalorimetry for toxicity testing draw the attention to a possible new tool to increase sensitivity, to eliminate matrix effect and to study effect-mechanism. A Thermal Activity Monitor (TAM) microcalorimeter was used for measuring the heat production of various test organisms when getting in contact with sterile toxic soils. Well known bacterial (Azomonas agilis), animal (Folsomia candida) and plant test organisms (Sinapis alba) were tested for heat production. The heat response of selected testorganisms was measured in case of metal (Cu and Zn) and organic pollutant (Diesel oil, DBNPA and PCP) contaminated soils. In addition to the quantitative determination of the heat production, the mechanism of the toxic effect can be characterized from the shape of the power-time curve (slope of the curve, height and time of the maximum). In certain concentration ranges the higher the pollutant concentration of the soil the lower the maximum of the time-heat curve. At low pollutant concentrations an increased heat production was measured in case of A. agile and 20 and 200 mg Zn kg(-1) soil. The microcalorimetric testing was more sensitive in all cases than the traditional test methods. Our results showed that the microcalorimetric test method offers a new and sensitive option in environmental toxicology, both for research and routine testing. PMID:20549622

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

    USGS Publications Warehouse

    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.

  9. Handbook of environmental fate and exposure data for organic chemicals

    SciTech Connect

    Howard, P.H. . Center for Chemical Hazard Assessment)

    1989-01-01

    This book allows for the assessment of the health and environmental effects of chemicals by determining the routes of exposure of the chemical to sensitive organisms. It provides relevant facts on how individual chemicals behave in the environment and how they are exposed to humans and environmental organisms during their production, use, transport, and disposal.

  10. Chemical aspects of incorporating contaminated soil into cold-mix asphalt

    SciTech Connect

    Testa, S.M.

    1994-12-31

    The chemical aspects associated with the incorporation of petroleum hydrocarbons- and metals-affected soil has been extensively studied in regards to pavement properties, leaching behavior, sensitivities to moisture-damage and function group analysis. These studies provide information that can be used to evaluate the stability of these constituents in soil that have been incorporated as an ingredient in asphalt. These studies also indicate that cold-mix asphalt incorporating contaminated soil will be highly stable and perform adequately as an end product. Maximum chemical performance is achieved when the asphalt is comprised of high contents of pyridinic, phenolic and ketone groups, which can be achieved by selectively choosing the source material. If the situation requires special stability or redundancy, small amounts of shale oil and lime can be used as additives. Situations and conditions which favor the presence of inorganic sulfur, monovalent salts and high strength solutions in the asphalt should be avoided since these conditions decrease the chemical stability of the asphalt cement by disruption of the functional group-aggregate bonds and by increasing the overall permeability. However, these conditions are not typically expected in the anticipated uses of asphalt cement to stabilize contaminants in soil using Environmentally Processed Asphalt{trademark} (EPA{trademark}) or Asphaltic Metals Stabilization{trademark} (AMS{trademark}) remedial technologies.

  11. [Environmental characterization of the National Contaminated Sites in SENTIERI project].

    PubMed

    Musmeci, L; Bellino, M; Falleni, F; Piccardi, A

    2011-01-01

    The concept of "polluted site" was firstly introduced in Italy with the definition of "environmental high risk areas" (Rule 349/86). Later, the decree 471/99 stated that a site is considered polluted if the concentration of even just one index pollutant in anyone of the matrices (soil or subsoil, surface or ground waters) exceeds the allowable threshold limit concentration. The boundaries of Italian polluted sites (IPS) were defined (Decree 152/06) on the basis of health, environmental and social criteria. SENTIERI Project includes 44 out of the 57 sites comprised in the "National environmental remediation program"; they correspond to the largest national industrial agglomerates. For each site, characterization data were collected, classified and arranged in tables. A great part of collected data came also from the environmental remediation programmes planned for the sites. These plans show that characterization and risk assessment activities were mainly undertaken for private industrial areas, as they were considered source of pollution. On the other hand, municipal and/or green and agricultural areas included in IPSs were poorly studied. Therefore, it is difficult to assess the exposure of the populations living inside and/or near the IPSs. The most probable population exposure come from the contamination of ground waters utilized for irrigation, or industrial emissions. For a description of SENTIERI, refer to the 2010 Supplement of Epidemiology & Prevention devoted to SENTIERI Project. PMID:22166293

  12. The impact of environmental chemicals on wildlife vertebrates.

    PubMed

    Bernanke, Julia; Khler, Heinz-R

    2009-01-01

    A plethora of papers have been published that address the affects of chemicals on wildlife vertebrates. Collectively, they support a connection between environmental pollution and effects on wildlife vertebrate populations; however, causal relationships between exposure, and reproduction or population structure effects have been established for only a few species. In a vast number of fish species, particularly in teleosts, it is accepted that EDCs affect the endocrine system of individuals and may alter sexual development and fertility. However, only few studies have demonstrated population-level consequences as a result of exposure to EDCs. The same applies to fish populations exposed to contaminants or contaminant mixtures with non-endocrine modes of action; few studies link EDCs directly to population affects. Amphibian populations are declining in many parts of the world. Although environmental chemicals have been shown to affect reproduction and development in single organism tests, the degree to which chemicals contribute to the decline of amphibians, either alone, or in concert with other factors (habitat loss, climate change, introduction of neozoa, UV-B irradiation, and direct exploitation) is still uncertain. Because reptilian endocrinology is so variable among species, EDC effects reported for individual species cannot easily be extrapolated to others. Nevertheless, for some species and locations (e.g., the Lake Popka alligators), there is considerable evidence that population declines are caused or triggered by chemical pollution. In birds, there is ample evidence for EDC effects on the reproductive system. In some bird species, effects can be linked to population declines (e.g., based on egg-shell thinning induced by DDT/DDE). In contrast, other bird species were shown to be rather insensitive to endocrine disruption. Oil spills, which also may exert endocrine effects, are usually regarded to cause only transient bird population effects, although long-term data are largely missing. Mammal population declines have been correlated with organochlorine pollution. Moreover, numerous studies have attributed reproductive and non-reproductive dysfunctions in mammals to EDC exposure. However, in the majority of cases, it is uncertain if effects at the population level can be attributed to chemical-induced reproductive effects. Evidence shows that selected species from all vertebrate classes were negatively affected by certain anthropogenic chemicals. Affects on some species are well characterized at the organismal level. However, the proof of a direct link between chemical exposure and population decline was not given for the vast majority of studied species. This review clearly shows the gaps in knowledge that must be filled for the topic area addressed. We, herewith, make a plea for long-term studies to monitor effects of various environmental chemicals on wildlife vertebrate populations. Such studies may be augmented or combined with mechanistically-oriented histological, cytological and biochemical parallel investigations, to fill knowledge gaps. PMID:19253040

  13. PROSPECTS FOR IN SITU CHEMICAL TREATMENT FOR CONTAMINATED SOIL

    EPA Science Inventory

    Treating large volumes of contaminated soil at Superfund sites is costly. he Superfund Amendments and Reauthorization Act (SARA), and the Resource Conservation and Recovery Act (RCRA) have provisions, which regulate the removal treatment, and ultimate disposal of contaminated soi...

  14. Carcinogenicity of consumption of red and processed meat: What about environmental contaminants?

    PubMed

    Domingo, José L; Nadal, Martí

    2016-02-01

    In October 26, 2015, the International Agency for Research on Cancer (IARC) issued a press release informing of the recent evaluation of the carcinogenicity of red and processed meat consumption. The consumption of red meat and processed meat was classified as "probably carcinogenic to humans", and as "carcinogenic to humans", respectively. The substances responsible of this potential carcinogenicity would be generated during meat processing, such as curing and smoking, or when meat is heated at high temperatures (N-nitroso-compounds, polycyclic aromatic hydrocarbons and heterocyclic aromatic amines). However, in its assessments, the IARC did not make any reference to the role that may pose some carcinogenic environmental pollutants, which are already present in raw or unprocessed meat. The potential role of a number of environmental chemical contaminants (toxic trace elements, polycyclic aromatic hydrocarbons, polychlorinated dibenzo-p-dioxins and dibenzofurans, polychlorinated biphenyls, polybrominated diphenyl ethers, polychlorinated diphenyl ethers, polychlorinated naphthalenes and perfluoroalkyl substances) on the carcinogenicity of consumption of meat and meat products is discussed in this paper. A case-study, Catalonia (Spain), is specifically assessed, while the influence of cooking on the concentrations of environmental pollutants is also reviewed. It is concluded that although certain cooking processes could modify the levels of chemical contaminants in food, the influence of cooking on the pollutant concentrations depends not only on the particular cooking process, but even more on their original contents in each specific food item. As most of these environmental pollutants are organic, cooking procedures that release or remove fat from the meat should tend to reduce the total concentrations of these contaminants in the cooked meat. PMID:26656511

  15. Analytic considerations for measuring environmental chemicals in breast milk.

    PubMed Central

    Needham, Larry L; Wang, Richard Y

    2002-01-01

    The presence of environmental chemicals in human breast milk is of general concern because of the potential health consequence of these chemicals to the breast-fed infant and the mother. In addition to the mother's exposure, several features determine the presence of environmental chemicals in breast milk and their ability to be determined analytically. These include maternal factors and properties of the environmental chemical--both physical and chemical--such as its lipid solubility, degree of ionization, and molecular weight. Environmental chemicals with high lipid solubility are likely to be found in breast milk; they include polyhalogenated compounds such as polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, organochlorine insecticides, and polybrominated diphenylethers. These fat-soluble chemicals are incorporated into the milk as it is synthesized, and they must be measured in accordance with the fat content of the milk to allow for meaningful comparisons within an individual and among populations. Although the analytic approach selected to measure the environmental chemical is predominantly determined by the characteristics of the chemical, the concentration of the chemical in the milk sample and the existence of structurally similar chemicals (e.g., congeners) must be considered as well. In general, the analytic approach for measuring environmental chemicals in breast milk is similar to the approach for measuring the same chemicals in other matrices, except special considerations must be given for the relatively high fat content of milk. The continued efforts of environmental scientists to measure environmental chemicals in breast milk is important for defining the true contribution of these chemicals to public health, especially to the health of the newborn. Work is needed for identifying and quantifying additional environmental chemicals in breast milk from the general population and for developing analytic methods that have increased sensitivity and the ability to speciate various chemicals. PMID:12055062

  16. Contaminant exposures in various environmental media: How can toxicity comparisons be made?

    SciTech Connect

    Lanno, R.P.; McCarty, L.S.

    1995-12-31

    Environmental protection is usually based upon guidelines or standards expressed as chemical values in environmental media such as air, sediment, soil, and water. The basis for such guidelines is laboratory toxicity test data, often time-dependent LC50 values (e.g., 96-h LC50s), where toxicity is expressed in terms of the concentration of chemical contaminant in the exposure medium. This preoccupation with exposure-based estimates of toxic dose has led to many difficulties when attempting to compare the relative toxicity of compounds between species and under various modifying conditions in the same medium. Furthermore, viable comparisons of toxic potencies between organisms inhabiting different environmental media has been all but impossible. This paper exploits the relationship between body residues and adverse biological effects to compare the effects of certain modifying factors (e.g., temperature) on expressed toxicity and toxic potency both within and between different species in one medium. As well, this approach is used to make comparisons of toxic potency between different species in different environmental media. Such comparisons are made by standardizing toxic responses to time-independent toxicity thresholds and using the critical body residue at the chosen biological response endpoint as the dose surrogate rather than the concentration of chemical in the exposure medium. Comparisons of exposure-based and organism residue-based toxicity between fish, and invertebrates in soil (earthworms) and sediment (amphipods) are presented. Recommendations to facilitate such comparisons are reviewed.

  17. Assessment of Environmental Contamination and Environmental Decontamination Practices within an Ebola Holding Unit, Freetown, Sierra Leone

    PubMed Central

    Youkee, Daniel; Brown, Colin S.; Lilburn, Paul; Shetty, Nandini; Brooks, Tim; Simpson, Andrew; Bentley, Neil; Lado, Marta; Kamara, Thaim B.; Walker, Naomi F.; Johnson, Oliver

    2015-01-01

    Evidence to inform decontamination practices at Ebola holding units (EHUs) and treatment centres is lacking. We conducted an audit of decontamination procedures inside Connaught Hospital EHU in Freetown, Sierra Leone, by assessing environmental swab specimens for evidence of contamination with Ebola virus by RT-PCR. Swabs were collected following discharge of Ebola Virus Disease (EVD) patients before and after routine decontamination. Prior to decontamination, Ebola virus RNA was detected within a limited area at all bedside sites tested, but not at any sites distant to the bedside. Following decontamination, few areas contained detectable Ebola virus RNA. In areas beneath the bed there was evidence of transfer of Ebola virus material during cleaning. Retraining of cleaning staff reduced evidence of environmental contamination after decontamination. Current decontamination procedures appear to be effective in eradicating persistence of viral RNA. This study supports the use of viral swabs to assess Ebola viral contamination within the clinical setting. We recommend that regular refresher training of cleaning staff and audit of environmental contamination become standard practice at all Ebola care facilities during EVD outbreaks. PMID:26692018

  18. DEVELOPMENT OF A QUANTITATIVE ASSAY FOR VITELLOGENIN TO MONITOR ESTROGEN-LIKE ENVIRONMENTAL CONTAMINANTS

    EPA Science Inventory

    Many environmental contaminants have the potential to disrupt endocrine systems of wildlife and humans resulting in impairment of reproductive and other systems. A subset of these contaminants may initiate these effects by binding to the estrogen receptor. In oviparous vertebrate...

  19. Chemically enhanced phytoextraction of lead-contaminated soils.

    PubMed

    Perry, V Ryan; Krogstad, Eirik J; El-Mayas, Hanan; Greipsson, Sigurdur

    2012-08-01

    The effects of the combined application of soil fungicide (benomyl) and ethylenediaminetetraacetic acid (EDTA) on lead (Pb) phytoextraction by ryegrass (Lolium perenne) were examined. Twenty-five pots of Pb-contaminated soil (200 mg Pb kg(-1)) were seeded with ryegrass and randomly arranged into the following treatments: (1) Control, (2) benomyl, (3) EDTA, (4) benomyl and EDTA (B+E), and (5) benomyl followed by an application of EDTA 14 days later (B .. . E). Chemicals were applied when plants had reached maximum growth. Plants were analyzed for foliage Pb concentration using inductively coupled argon plasma (ICAP) spectrometry. The synergistic effects of the combined benomyl and EDTA application (treatments 4 and 5) were made evident by the significantly (p < 0.05) highest foliage Pb concentrations. However, the foliage dry biomass was significantly lowest for plants in treatments 4 and 5. The bioaccumulation factor (BF) and phytoextraction ratio (PR) were highest for plants in treatment 5 followed by plants in treatment 4. PMID:22908638

  20. Cumulative Index to Chemicals and to Common and Scientific Names of Species Listed in Contaminant Hazard Reviews 1 through 34

    USGS Publications Warehouse

    Eisler, R.

    1999-01-01

    The Patuxent Wildlife Research Center Contaminant Hazard Reviews (CHR) series synthesizes ecotoxicological data of selected environmental contaminants, with emphasis on hazards to native species of flora and fauna. From 1985 through 1998 a total of 34 reviews were published in various Reports series of the U.S. Department of the Interior on agricultural pesticides (carbofuran, chlordane, chlorpyrifos, diazinon, diflubenzuron, fenvalerate, mirex, paraquat, toxaphene), herbicides (acrolein, atrazine), metals and metalloids (arsenic, boron, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, silver, tin, zinc), predacides (sodium monofluoroacetate), organic industrial wastes (dioxins, pentachlorophenol), veterinary chemicals (famphur), polycyclic aromatic hydrocarbons, polychlorinated biphenyls, mining wastes (cyanide), and ionizing radiations. This report is a cumulative index to the common and scientific names of all biological species listed in the first 34 reports in the CHR series, with individual species cross-referenced by contaminant and corresponding page numbers. A similar index is shown for chemicals.

  1. Thyroid hormone metabolism and environmental chemical exposure

    PubMed Central

    2012-01-01

    Background Polychlorinated dioxins and furans (PCDD/Fs) and polychlorinated-biphenyls (PCBs) are environmental toxicants that have been proven to influence thyroid metabolism both in animal studies and in human beings. In recent years polybrominated diphenyl ethers (PBDEs) also have been found to have a negative influence on thyroid hormone metabolism. The lower brominated flame retardants are now banned in the EU, however higher brominated decabromo-diphenyl ether (DBDE) and the brominated flame retardant hexabromocyclododecane (HBCD) are not yet banned. They too can negatively influence thyroid hormone metabolism. An additional brominated flame retardant that is still in use is tetrabromobisphenol-A (TBBPA), which has also been shown to influence thyroid hormone metabolism. Influences of brominated flame retardants, PCDD/Fs and dioxin like-PCBs (dl-PCBs) on thyroid hormone metabolism in adolescence in the Netherlands will be presented in this study and determined if there are reasons for concern to human health for these toxins. In the period 1987-1991, a cohort of mother-baby pairs was formed in order to detect abnormalities in relation to dioxin levels in the perinatal period. The study demonstrated that PCDD/Fs were found around the time of birth, suggesting a modulation of the setpoint of thyroid hormone metabolism with a higher 3,3, 5,5tetrathyroxine (T4) levels and an increased thyroid stimulating hormone (TSH). While the same serum thyroid hormone tests (- TSH and T4) were again normal by 2 years of age and were still normal at 8-12 years, adolescence is a period with extra stress on thyroid hormone metabolism. Therefore we measured serum levels of TSH, T4, 3,3,5- triiodothyronine (T3), free T4 (FT4), antibodies and thyroxine-binding globulin (TBG) in our adolescent cohort. Methods Vena puncture was performed to obtain samples for the measurement of thyroid hormone metabolism related parameters and the current serum dioxin (PCDD/Fs), PCB and PBDE levels. Results The current levels of T3 were positively correlated to BDE-99. A positive trend with FT4 and BDE-99 was also seen, while a positive correlation with T3 and dl-PCB was also seen. No correlation with TBG was seen for any of the contaminants. Neither the prenatal nor the current PCDD/F levels showed a relationship with the thyroid parameters in this relatively small group. Conclusion Once again the thyroid hormone metabolism (an increase in T3) seems to have been influenced by current background levels of common environmental contaminants: dl-PCBs and BDE-99. T3 is a product of target organs and abnormalities might indicate effects on hormone transporters and could cause pathology. While the influence on T3 levels may have been compensated, because the adolescents functioned normal at the time of the study period, it is questionable if this compensation is enough for all organs depending on thyroid hormones. PMID:22759492

  2. The toxicology of climate change: environmental contaminants in a warming world.

    PubMed

    Noyes, Pamela D; McElwee, Matthew K; Miller, Hilary D; Clark, Bryan W; Van Tiem, Lindsey A; Walcott, Kia C; Erwin, Kyle N; Levin, Edward D

    2009-08-01

    Climate change induced by anthropogenic warming of the earth's atmosphere is a daunting problem. This review examines one of the consequences of climate change that has only recently attracted attention: namely, the effects of climate change on the environmental distribution and toxicity of chemical pollutants. A review was undertaken of the scientific literature (original research articles, reviews, government and intergovernmental reports) focusing on the interactions of toxicants with the environmental parameters, temperature, precipitation, and salinity, as altered by climate change. Three broad classes of chemical toxicants of global significance were the focus: air pollutants, persistent organic pollutants (POPs), including some organochlorine pesticides, and other classes of pesticides. Generally, increases in temperature will enhance the toxicity of contaminants and increase concentrations of tropospheric ozone regionally, but will also likely increase rates of chemical degradation. While further research is needed, climate change coupled with air pollutant exposures may have potentially serious adverse consequences for human health in urban and polluted regions. Climate change producing alterations in: food webs, lipid dynamics, ice and snow melt, and organic carbon cycling could result in increased POP levels in water, soil, and biota. There is also compelling evidence that increasing temperatures could be deleterious to pollutant-exposed wildlife. For example, elevated water temperatures may alter the biotransformation of contaminants to more bioactive metabolites and impair homeostasis. The complex interactions between climate change and pollutants may be particularly problematic for species living at the edge of their physiological tolerance range where acclimation capacity may be limited. In addition to temperature increases, regional precipitation patterns are projected to be altered with climate change. Regions subject to decreases in precipitation may experience enhanced volatilization of POPs and pesticides to the atmosphere. Reduced precipitation will also increase air pollution in urbanized regions resulting in negative health effects, which may be exacerbated by temperature increases. Regions subject to increased precipitation will have lower levels of air pollution, but will likely experience enhanced surface deposition of airborne POPs and increased run-off of pesticides. Moreover, increases in the intensity and frequency of storm events linked to climate change could lead to more severe episodes of chemical contamination of water bodies and surrounding watersheds. Changes in salinity may affect aquatic organisms as an independent stressor as well as by altering the bioavailability and in some instances increasing the toxicity of chemicals. A paramount issue will be to identify species and populations especially vulnerable to climate-pollutant interactions, in the context of the many other physical, chemical, and biological stressors that will be altered with climate change. Moreover, it will be important to predict tipping points that might trigger or accelerate synergistic interactions between climate change and contaminant exposures. PMID:19375165

  3. [Proposal to establish an environmental contaminants surveillance system in Colombia].

    PubMed

    Huertas, Jancy Andrea

    2015-08-01

    Environmental pollution is a growing problem that negatively impacts health with social and economic high costs. In this sense, coordinated surveillance of conditions, risks, exposures and health effects related to pollution is a useful tool to guide decision-making processes. The objective of this essay was to describe a surveillance system for environmental contaminants in Colombia and its design background. Using the technical guidelines proposed by the Pan American Health Organization, a literature review was conducted to identify the key elements to be included in such surveillance system and to establish which of these elements were already present in the Colombian context. Moreover, these findings were compared with successful experiences in Latin America. The surveillance system includes five components: Epidemiological, environmental and biological surveillance, clinical monitoring and recommendations to guide policies or interventions. The key factors for a successful surveillance system are: interdisciplinary and inter-sector work, clear definition of functions, activities, data sources and information flow. The implementation of the system will be efficient if the structures and tools existing in each country are taken into account. The most important stakeholders are inter-sector public health and environmental commissions and government institutions working in research and surveillance issues related to health, sanitation, environment, drugs and food regulation and control. In conclusion, Colombia has the technical resources and a normative framework to design and implement the surveillance system. However, stakeholders coordination is essential to ensure the efficacy of the system so it may guide the implementation of cost-effective actions in environmental health. PMID:26535737

  4. DESIGNING ENVIRONMENTALLY FRIENDLY CHEMICAL PROCESSES WITH FUGITIVE AND OPEN EMISSIONS

    EPA Science Inventory

    Designing a chemical process normally includes aspects of economic and environmental disciplines. In this work we describe methods to quickly and easily evaluate the economics and potential environmental impacts of a process, with the hydrodealkylation of toluene as an example. ...

  5. Integrated Proteomic Approaches for Understanding Toxicity of Environmental Chemicals

    EPA Science Inventory

    To apply quantitative proteomic analysis to the evaluation of toxicity of environmental chemicals, we have developed an integrated proteomic technology platform. This platform has been applied to the analysis of the toxic effects and pathways of many important environmental chemi...

  6. A norovirus outbreak associated with environmental contamination at a hotel.

    PubMed

    Kimura, H; Nagano, K; Kimura, N; Shimizu, M; Ueno, Y; Morikane, K; Okabe, N

    2011-02-01

    SUMMARYIn December 2006, an outbreak of gastroenteritis occurred involving 372 guests and 72 employees at a hotel after a guest vomited in corridors on the third (F3) and 25th (F25) floors. Norovirus with identical genotype was confirmed by real-time reverse transcription-polymerase chain reaction in faecal samples from guest cases and employees. Spread of the outbreak on F25 was compared with that on F3. The attack rate in the guests who visited F25 alone (15·0%, 106/708 guests) was significantly higher than in those who visited F3 alone (3·5%, 163/4710 guests) (relative risk 4·3, 95% confidence interval 3·4-5·5, P < 0·001). The outbreak on F3 ended within 2 days, while that on F25 extended over 7 days. The environmental ratios of F3 to F25 were 7·4 for volume, 6·9 for floor area and 7·6 for ventilation rate. This outbreak suggests that environmental differences can affect the propagation and persistence of a norovirus outbreak following environmental contamination. PMID:20429969

  7. Environmental stability of chemically amplified resists: proposing an industry standard methodology for testing

    NASA Astrophysics Data System (ADS)

    Dean, Kim R.; Kishkovich, Oleg P.

    2000-06-01

    The authors propose the establishment of a new industry standard methodology for testing the environmental stability of chemically amplified chemical resists. Preparatory to making this proposal, they developed a pertinent test apparatus and test procedure that might be used uniformly as an industry-wide best practice. To demonstrate and validate their proposed methodology, the authors subjected two different 193 nm chemically amplified photoresists to test conditions in the 'torture chamber,' simulating actual lithographic environmental scenarios. Depending on the variables of each test run (e.g., different resists, different resist thicknesses, different pollutants, different concentrations, and different humidity levels), a variety of defects were noted and described quantitatively. Of the three contaminants tested, ammonia had the strongest effect. The thin resists were more strongly affected by the contamination.

  8. Treatment of hydrocarbon contamination under flow through conditions by using magnetite catalyzed chemical oxidation.

    PubMed

    Usman, M; Faure, P; Lorgeoux, C; Ruby, C; Hanna, K

    2013-01-01

    Soil pollution by hydrocarbons (aromatic and aliphatic hydrocarbons) is a major environmental issue. Various treatments have been used to remove them from contaminated soils. In our previous studies, the ability of magnetite has been successfully explored to catalyze chemical oxidation for hydrocarbon remediation in batch slurry system. In the present laboratory study, column experiments were performed to evaluate the efficiency of magnetite catalyzed Fenton-like (FL) and activated persulfate (AP) oxidation for hydrocarbon degradation. Flow-through column experiments are intended to provide a better representation of field conditions. Organic extracts isolated from three different soils (an oil-contaminated soil from petrochemical industrial site and two soils polluted by polycyclic aromatic hydrocarbon (PAH) originating from coking plant sites) were spiked on sand. After solvent evaporation, spiked sand was packed in column and was subjected to oxidation using magnetite as catalyst. Oxidant solution was injected at a flow rate of 0.1 mL min(-1) under water-saturated conditions. Organic analyses were performed by GC-mass spectrometry, GC-flame ionization detector, and micro-Fourier transform infrared spectroscopy. Significant abatement of both types of hydrocarbons (60-70 %) was achieved after chemical oxidation (FL and AP) of organic extracts. No significant by-products were formed during oxidation experiment, underscoring the complete degradation of hydrocarbons. No selective degradation was observed for FL with almost similar efficiency towards all hydrocarbons. However, AP showed less reactivity towards higher molecular weight PAHs and aromatic oxygenated compounds. Results of this study demonstrated that magnetite-catalyzed chemical oxidation can effectively degrade both aromatic and aliphatic hydrocarbons (enhanced available contaminants) under flow-through conditions. PMID:22684901

  9. A Framework for the Environmental Professional in the Chemical Industry.

    ERIC Educational Resources Information Center

    Priesing, Charles P.

    1982-01-01

    Addresses four areas of environmental concern in the chemical industry: (1) needs and responsibilities of environmental protection; (2) organization and distribution of environmental affairs within the corporate structure; (3) functions and operations associated with industrial environmental management; and (4) origins and tasks of the

  10. Impaired immunity in harbour seals (Phoca vitulina) exposed to bioaccumulated environmental contaminants: review of a long-term feeding study.

    PubMed Central

    de Swart, R L; Ross, P S; Vos, J G; Osterhaus, A D

    1996-01-01

    Mass mortalities among seals and dolphins inhabiting contaminated marine regions have led to speculation about a possible involvement of immunosuppression associated with environmental pollution. To evaluate whether contaminants at ambient environmental levels can affect immune function of seals, we carried out an immunotoxicological study under semifield conditions. Two groups of 11 harbour seals (Phoca vitulina) originating from a relatively uncontaminated area were fed herring from either the highly polluted Baltic Sea or the relatively uncontaminated Atlantic Ocean. Changes in immune function were monitored over a 2 1/2-year period. The seals that were fed contaminated Baltic herring developed significantly higher body burdens of potentially immunotoxic organochlorines and displayed impaired immune responses as demonstrated by suppression of natural killer cell activity and specific T-cell responses. During a 2-week fasting experiment performed at the end of the feeding study, mobilization of organochlorines from the blubber did not lead to a strong increase of contaminant levels in the blood, and no enhancement of the existing immunosuppression was observed. These results demonstrate that chronic exposure to environmental contaminants accumulated through the food chain affects immune function in harbour seals, whereas short-term fasting periods, which are normal for seals, do not seem to pose an additional risk. The seals of this study were not exposed perinatally to high levels of environmental chemicals, and body burdens of organochlorines measured near the end of the study were lower than those generally observed in free-ranging seals inhabiting many contaminated regions. Therefore, it may be expected that environmental contaminants adversely affect immune function of free-ranging seals inhabiting contaminated regions at least as seriously as observed in these studies. PMID:8880005

  11. Endocrine disruptor activity of multiple environmental food chain contaminants.

    PubMed

    Wielogórska, E; Elliott, C T; Danaher, M; Connolly, L

    2015-02-01

    Industrial chemicals, antimicrobials, drugs and personal care products have been reported as global pollutants which enter the food chain. Some of them have also been classified as endocrine disruptors based on results of various studies employing a number of in vitro/vivo tests. The present study employed a mammalian reporter gene assay to assess the effects of known and emerging contaminants on estrogen nuclear receptor transactivation. Out of fifty-nine compounds assessed, estrogen receptor agonistic activity was observed for parabens( n = 3), UV filters (n = 6), phthalates (n = 4) and a metabolite, pyrethroids (n = 9) and their metabolites (n = 3). Two compounds were estrogen receptor antagonists while some of the agonists enhanced 17b-estradiol mediated response.This study reports five new compounds (pyrethroids and their metabolites) possessing estrogen agonist activity and highlights for the first time that pyrethroid metabolites are of particular concern showing much greater estrogenic activity than their parent compounds. PMID:25449125

  12. Mapping Proteome-Wide Targets of Environmental Chemicals Using Reactivity-Based Chemoproteomic Platforms.

    PubMed

    Medina-Cleghorn, Daniel; Bateman, Leslie A; Ford, Breanna; Heslin, Ann; Fisher, Karl J; Dalvie, Esha D; Nomura, Daniel K

    2015-10-22

    We are exposed to a growing number of chemicals in our environment, most of which have not been characterized in terms of their toxicological potential or mechanisms. Here, we employ a chemoproteomic platform to map the cysteine reactivity of environmental chemicals using reactivity-based probes to mine for hyper-reactive hotspots across the proteome. We show that environmental contaminants such as monomethylarsonous acid and widely used pesticides such as chlorothalonil and chloropicrin possess common reactivity with a distinct set of proteins. Many of these proteins are involved in key metabolic processes, suggesting that these targets may be particularly sensitive to environmental electrophiles. We show that the widely used fungicide chlorothalonil specifically inhibits several metabolic enzymes involved in fatty acid metabolism and energetics, leading to dysregulated lipid metabolism in mice. Our results underscore the utility of using reactivity-based chemoproteomic platforms to uncover novel mechanistic insights into the toxicity of environmental chemicals. PMID:26496688

  13. Clostridium difficile in a children's hospital: assessment of environmental contamination.

    PubMed

    Warrack, Simone; Duster, Megan; Van Hoof, Sarah; Schmitz, Michelle; Safdar, Nasia

    2014-07-01

    Clostridium difficile infection (CDI) is the most frequent infectious cause of health care-associated diarrhea. Three cases of CDI, in children age 2, 3, and 14 years, occurred in the hematology/oncology ward of our children's hospital over 48 hours. We aimed to assess environmental contamination with C difficile in the shared areas of this unit, and to determine whether person-to-person transmission occurred. C difficile was recovered from 5 of 18 samples (28%). We compared C difficile isolated from each patient and the environment using pulsed-field gel electrophoresis, and found that none of the patient strains matched any of the others, and that none matched any strains recovered from the environment, suggesting that person-to-person transmission had not occurred. We found that C difficile was prevalent in the environment throughout shared areas of the children's hospital unit. Molecular typing to identify mechanisms of transmission is useful for devising appropriate interventions. PMID:24751141

  14. A Model for Measurements of Lognormally Distributed Environmental Contaminants

    SciTech Connect

    Charles B. Davis, Danny Field, Thomas E. Gran

    2009-05-21

    This paper proposes a more nearly reasonable model for the actual measurement distribution, called here the Davis Mixed Model (DMM). The DMM is derived by multiplying the probability density function of unobservable actual concentrations (assumed LN) by the conditional density of measurements given the concentrations (assumed heteroscedastic normal), and then integrating to obtain the marginal distribution of the observable measurements. The DMM is complicated and analytically intractable; its probability density function (PDF) is itself an integral, for example, and closed-form expressions for percentiles, let alone estimators, do not exist. The DMM can be fit to data via Maximum Likelihood Estimation (MLE), however, and a fitted model can be used to generate data for evaluating the actual performance of candidate UTL or other estimation procedures. The Industrial Hygiene application motivating this work involves surface sampling surveys for removable beryllium (Be) contamination, with data from Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) analyses. Similar issues will arise quite generally with censored environmental data for other contaminants and analytical methods. The conclusions presented in this paper focus on the regions of the DMM parameter space arising in surveying numerous Department of Energy (DOE) facilities associated with the Nevada Test Site (NTS).

  15. Determination of selected environmental contaminants in foraging honeybees.

    PubMed

    Garca-Valcrcel, A I; Molero, Encarnacin; Tadeo, J L; Hernando, M D

    2016-02-01

    Colony losses of honeybees have been of great concern in the last years. To explain these losses, several studies have been reported, and various factors, such as pathogens and pesticides, have been considered as possible causes. Nevertheless, organic contaminants, rather than pesticides, are continuously released to the environment, and can be intercepted by honeybees during foraging with the possible consequent damage. Azoles and organophosphorus esters have been selected in this work as environmental contaminants to be monitored in honeybees. A fast and robust method has been developed to determine these organic pollutants in honeybees. It is based on matrix solid phase dispersion (MSPD), which performs sample dispersion with extraction and clean up in the same step, followed by LC-ESI-MS/MS determination. Recoveries of the method varied between 73% and 119% and MQLs ranged from 0.8 to 4 ngg(-1). Honeybee samples from ten apiaries located in different regions were analyzed applying the developed method. Azole compounds were found at low levels, but not in all samples, while organophosphorus esters were found in most samples whatever location. Tris-(2-chloroisopropyl) phosphate, TCPP, and tributyl phosphate, TBP, were detected in all honeybees samples at levels higher than the rest of organophosphates analyzed. PMID:26653416

  16. Remediation of soils contaminated with particulate depleted uranium by multi stage chemical extraction.

    PubMed

    Crean, Daniel E; Livens, Francis R; Sajih, Mustafa; Stennett, Martin C; Grolimund, Daniel; Borca, Camelia N; Hyatt, Neil C

    2013-12-15

    Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction. Uranium rich particles with characteristic spherical morphologies were observed in soils, consistent with other instances of DU munitions contamination. Batch extraction efficiencies for aqueous ammonium bicarbonate (42-50% total DU extracted), citric acid (30-42% total DU) and sulphuric acid (13-19% total DU) were evaluated. Characterisation of residues from bicarbonate-treated soils by synchrotron microfocus X-ray diffraction and X-ray absorption spectroscopy revealed partially leached U(IV)-oxide particles and some secondary uranyl-carbonate phases. Based on these data, a multi-stage extraction scheme was developed utilising leaching in ammonium bicarbonate followed by citric acid to dissolve secondary carbonate species. Site specific U extraction was improved to 68-87% total U by the application of this methodology, potentially providing a route to efficient DU decontamination using low cost, environmentally compatible reagents. PMID:23998894

  17. In situ chemical fixation of arsenic-contaminated soils: Anexperimental study

    SciTech Connect

    Yang, Li; Donahoe, Rona J.; Redwine, James C.

    2007-03-27

    This paper reports the results of an experimentalstudytesting a low-cost in situ chemical fixation method designed to reclaimarsenic-contaminated subsurface soils. Subsurface soils from severalindustrial sites in southeastern U.S. were contaminated with arsenicthrough heavy application of herbicide containing arsenic trioxide. Themean concentrations of environmentally available arsenic in soilscollected from the two study sites, FW and BH, are 325 mg/kg and 900mg/kg, respectively. The soils are sandy loams with varying mineralogicaland organic contents. The previous study [Yang L, Donahoe RJ. The form,distribution and mobility of arsenic in soils contaminated by arsenictrioxide, at sites in Southeast USA. Appl Geochem 2007;22:320 341]indicated that a large portion of the arsenic in both soils is associatedwith amorphous aluminum and iron oxyhydroxides and shows very slowrelease against leaching by synthetic precipitation. The soil's amorphousaluminum and iron oxyhydroxides content was found to have the mostsignificant effect on its ability to retain arsenic.Based on thisobservation, contaminated soils were reacted with different treatmentsolutions in an effort to promote the formation of insolublearsenic-bearing phases and thereby decrease the leachability of arsenic.Ferrous sulfate, potassium permanganate and calcium carbonate were usedas the reagents for the chemical fixation solutions evaluated in threesets of batch experiments: (1) FeSO4; (2) FeSO4 and KMnO4; (3) FeSO4,KMnO4 and CaCO3. The optimum treatment solutions for each soil wereidentified based on the mobility of arsenic during sequential leaching oftreated and untreated soils using the fluids described in EPA Method 1311[USEPA. Method 1311: toxicity characteristic leaching procedure. Testmethods for evaluating solid waste, physical/chemical methods. 3rd ed.Washington, DC: U.S. Environmental Protection Agency, Office of SolidWaste. U.S. Government Printing Office; 1992]toxic characteristicsleaching procedure (TCLP) and EPA Method 1312 [USEPA.Method 1312:synthetic precipitation leaching procedure. Test methods for evaluatingsolid waste, physical/chemical methods. 3rd ed. Washington, DC: U.S.Environmental Protection Agency, Office of Solid Waste. U.S. GovernmentPrinting Office; 1994]synthetic precipitation leaching procedure(SPLP).Both FW and BH soils showed significant decreases in arsenicleachability for all three treatment solutions, compared to untreatedsoil. While soils treated with solution (3) showed the best results withsubsequent TCLP sequential leaching, SPLP sequential leaching of treatedsoils indicated that lowest arsenic mobility was obtained using treatmentsolution (1). Treatment solution (1) with only FeSO4 is considered thebest choice for remediation of arsenic-contaminated soil because SPLPsequential leaching better simulates natural weathering. Analysis oftreated soils produced no evidence of newly-formed arsenic-bearing phasesin either soil after treatment. Sequential chemical extractions oftreated soils indicate that surface complexation of arsenic on ferrichydroxide is the major mechanism for the fixation process.

  18. Analysis of environmental contamination resulting from catastrophic incidents: part 1. Building and sustaining capacity in laboratory networks.

    PubMed

    Magnuson, Matthew; Ernst, Hiba; Griggs, John; Fitz-James, Schatzi; Mapp, Latisha; Mullins, Marissa; Nichols, Tonya; Shah, Sanjiv; Smith, Terry; Hedrick, Elizabeth

    2014-11-01

    Catastrophic incidents, such as natural disasters, terrorist attacks, and industrial accidents, can occur suddenly and have high impact. However, they often occur at such a low frequency and in unpredictable locations that planning for the management of the consequences of a catastrophe can be difficult. For those catastrophes that result in the release of contaminants, the ability to analyze environmental samples is critical and contributes to the resilience of affected communities. Analyses of environmental samples are needed to make appropriate decisions about the course of action to restore the area affected by the contamination. Environmental samples range from soil, water, and air to vegetation, building materials, and debris. In addition, processes used to decontaminate any of these matrices may also generate wastewater and other materials that require analyses to determine the best course for proper disposal. This paper summarizes activities and programs the United States Environmental Protection Agency (USEPA) has implemented to ensure capability and capacity for the analysis of contaminated environmental samples following catastrophic incidents. USEPA's focus has been on building capability for a wide variety of contaminant classes and on ensuring national laboratory capacity for potential surges in the numbers of samples that could quickly exhaust the resources of local communities. USEPA's efforts have been designed to ensure a strong and resilient laboratory infrastructure in the United States to support communities as they respond to contamination incidents of any magnitude. The efforts include not only addressing technical issues related to the best-available methods for chemical, biological, and radiological contaminants, but also include addressing the challenges of coordination and administration of an efficient and effective response. Laboratory networks designed for responding to large scale contamination incidents can be sustained by applying their resources during incidents of lesser significance, for special projects, and for routine surveillance and monitoring as part of ongoing activities of the environmental laboratory community. PMID:24534702

  19. Review of chemical and radiotoxicological properties of polonium for internal contamination purposes

    SciTech Connect

    Ansoborlo, Eric; Berard, Philippe; Den Auwer, Christophe; Leggett, Richard Wayne; Menetrier, Florence; Younes, Ali; Montavon, Gilles; Moisy, Phillipe

    2012-01-01

    The discovery of polonium (Po) was first published in July 1898 by P. and M. Curie. It was the first element to be discovered by the radiochemical method. Polonium can be considered as a famous but neglected element: only a few studies of polonium chemistry have been published, mostly between 1950 and 1990. The recent (2006) event in which 2106 Po evidently was used as a poison to kill A. Litvinenko has raised new interest in polonium. 2011 being the 100th 8 anniversary of Marie Curie Nobel Prize in Chemistry, the aim of this paper is to review several aspect of polonium linked to its chemical properties and its radiotoxicity, including : i) its radiochemistry and interaction with matter; ii) its main sources and uses; iii) its physico-chemical properties; iv) its main analytical methods; v) its background exposure risk in water, food, and other environmental media; vi) its biokinetics and distribution following inhalation, ingestion and wound contamination; vii) its dosimetry and viii) treatments available (decorporation) in case of internal contamination.

  20. Environmental Contamination with Hazardous Drugs in Quebec Hospitals

    PubMed Central

    Bussires, Jean-Franois; Tanguay, Cynthia; Touzin, Karine; Langlois, ric; Lefebvre, Michel

    2012-01-01

    Background Since publication of the US National Institute for Occupational Safety and Health alert on hazardous drugs in 2004, many health care organizations have reviewed their procedures for handling hazardous drugs. Occupational exposure may occur when handling, compounding, or administering a drug considered to be hazardous, at any stage from storage to waste management. Objectives: To describe environmental contamination with cyclophosphamide, ifosfamide, and methotrexate in pharmacy and patient care areas of Quebec hospitals. Methods: Sixty-eight hospitals were invited to participate. At each hospital, 12 prespecified measurement sites (6 each within pharmacy and patient care areas) were sampled once (midweek, end of day). The samples were analyzed by ultra-performance liquid chromatography tandem mass spectrometry to determine the presence of the 3 drugs. The limits of detection (LODs) were 0.0015 ng/cm2 for cyclophosphamide, 0.0012 ng/cm2 for ifosfamide, and 0.0060 ng/cm2 for methotrexate. Results: Twenty-five (37%) of the hospitals agreed to participate. Samples from sites other than the 12 prespecified sites were excluded. Overall, 259 valid samples were collected between April 2008 and January 2010 (147 samples from pharmacy areas in 25 hospitals and 112 samples from patient care areas in 24 hospitals). No hospital was using a closed-system drug transfer device at the time of the study. The median (minimum, maximum) number of sites per hospital with at least 1 positive sample for at least 1 of the 3 hazardous drugs was 6 (1, 12). A total of 135 (52%) samples were positive for cyclophosphamide, 53 (20%) for ifosfamide, and 7 (3%) for methotrexate. The median (minimum, maximum) concentration in positive samples was 0.0035 ng/cm2 (below LOD, 28 ng/cm2) for cyclophosphamide, below LOD (below LOD, 8.6 ng/cm2) for ifosfamide, and below LOD (below LOD, 0.58 ng/cm2) for methotrexate. Conclusions: The levels of environmental contamination with 3 hazardous drugs in this multicentre study were similar to or below those in most published studies. Periodic measurement of surface contamination is necessary to ensure that current practices limit occupational exposure to hazardous drugs. PMID:23288952

  1. Cord serum immunoglobulin E related to the environmental contamination of human placentas with organochlorine compounds.

    PubMed Central

    Reichrtov, E; Ciznr, P; Prachar, V; Palkovicov, L; Veningerov, M

    1999-01-01

    Allergic diseases are on the rise in both prevalence and severity, especially in industrialized countries. The process of allergic sensitization needs an understanding of the role environmental factors play in its development. In addition to traditionally considered air pollutants, various persistent organochlorine pollutants, which accumulate in the human body over a lifetime via food intake, are toxic in humans. Placental contamination by chemicals may act as a biologic marker for the exposure of the mother or for the fetus via transplacental transfer. Placentas were collected from term deliveries in two Slovak regions. The samples were then analyzed for 21 selected organochlorine compounds. Specimens of cord blood from 2,050 neonates were gathered for the determination of levels of total immunoglobulin E (IgE). The regions were chosen according to their environmental characteristics: a city polluted with organic chemical industry versus a rural region devoid of industrial sources of pollution. In addition, data regarding the incidence rate of atopic eczema cases in the regions were considered. Comparisons between regions revealed that both the placental contamination with 16 of 21 organochlorine compounds and the cord serum IgE levels were significantly higher in the industrial region. The findings pointed to an association between organochlorine compounds and the higher levels of total IgE in newborns, signaling a higher allergic sensitization in the industrial region. This association was supported by the higher incidence rate of atopic eczema cases in the population registered in the industrial region. Images Figure 1 PMID:10544157

  2. Simulating Mobility of Chemical Contaminants from Unconventional Gas Development for Protection of Water Resources

    NASA Astrophysics Data System (ADS)

    Kanno, C.; Edlin, D.; Borrillo-Hutter, T.; McCray, J. E.

    2014-12-01

    Potential contamination of ground water and surface water supplies from chemical contaminants in hydraulic fracturing fluids or in natural gas is of high public concern. However, quantitative assessments have rarely been conducted at specific energy-producing locations so that the true risk of contamination can be evaluated. The most likely pathways for contamination are surface spills and faulty well bores that leak production fluids directly into an aquifer. This study conducts fate and transport simulations of the most mobile chemical contaminants, based on reactivity to subsurface soils, degradation potential, and source concentration, to better understand which chemicals are most likely to contaminate water resources, and to provide information to planners who wish to be prepared for accidental releases. The simulations are intended to be most relevant to the Niobrara shale formation.

  3. A risk-based methodology for ranking environmental chemical stressors at the regional scale.

    PubMed

    Giubilato, Elisa; Zabeo, Alex; Critto, Andrea; Giove, Silvio; Bierkens, Johan; Den Hond, Elly; Marcomini, Antonio

    2014-04-01

    A "Risk-based Tool for the Regional Ranking of Environmental Chemical Stressors" has been developed, aimed at supporting decision-makers in the identification of priority environmental contaminants, as well as priority areas, to be further assessed. The tool implements a methodology based on a quantitative Weight-of-Evidence approach, integrating three types of information, identified as "Lines-of-Evidence" (LoE), namely: LoE "Environmental Contamination" (including data on chemical contamination in environmental matrices in the region, thus providing information on potential population exposure), LoE "Intake" (including results from human biomonitoring studies, i.e. concentration of chemicals in human biological matrices, thus providing an integrated estimation of exposure) and LoE "Observed Effects" (including information on the incidence of adverse health outcomes associated with environmental exposure to chemicals). A Multi-Criteria Decision Analysis (MCDA) methodology based on fuzzy logic has been developed to support the integration of information related to these three LoEs for each chemical stressor. The tool allows one to rank chemical stressors at different spatial scales, such as at the regional level as well as within each sub-area (e.g., counties). Moreover, it supports the identification of priority sub-areas within the region, where environmental and health data suggest possible adverse health effects and thus more investigation efforts are needed. To evaluate the performance of this newly developed tool, a case-study in the Flemish region (north of Belgium) has been selected. In the case-study, data on soil contamination by metals and organic contaminants were integrated with data on exposure and effect biomarkers measured in adolescents within the framework of the human biomonitoring study performed by the Flemish Centre of Expertise on Environment and Health in the period 2002-2006. The case-study demonstrated the performance of the tool in integrating qualitative and quantitative data with expert judgement for the identification of priority contaminants and areas. The proposed approach proved to be flexible, allowing for the incorporation of individual decision-maker's preferences, and, at the same time, to be transparent since all assumptions and value attributions are traceable. PMID:24440801

  4. Rapid Electrochemical Detection and Identification of Microbiological and Chemical Contaminants for Manned Spaceflight Project

    NASA Technical Reports Server (NTRS)

    Pierson, Duane; Botkin, Douglas; Gazda, Daniel

    2014-01-01

    Microbial control in the spacecraft environment is a daunting task, especially in the presence of human crew members. Currently, assessing the potential crew health risk associated with a microbial contamination event requires return of representative environmental samples that are analyzed in a ground-based laboratory. It is therefore not currently possible to quickly identify microbes during spaceflight. This project addresses the unmet need for spaceflight-compatible microbial identification technology. The electrochemical detection and identification platform is expected to provide a sensitive, specific, and rapid sample-to-answer capability for in-flight microbial monitoring that can distinguish between related microorganisms (pathogens and non-pathogens) as well as chemical contaminants. This will dramatically enhance our ability to monitor the spacecraft environment and the health risk to the crew. Further, the project is expected to eliminate the need for sample return while significantly reducing crew time required for detection of multiple targets. Initial work will focus on the optimization of bacterial detection and identification. The platform is designed to release nucleic acids (DNA and RNA) from microorganisms without the use of harmful chemicals. Bacterial DNA or RNA is captured by bacteria-specific probe molecules that are bound to a microelectrode, and that capture event can generate a small change in the electrical current (Lam, et al. 2012. Anal. Chem. 84(1): 21-5.). This current is measured, and a determination is made whether a given microbe is present in the sample analyzed. Chemical detection can be accomplished by directly applying a sample to the microelectrode and measuring the resulting current change. This rapid microbial and chemical detection device is designed to be a low-cost, low-power platform anticipated to be operated independently of an external power source, characteristics optimal for manned spaceflight and areas where power and computing resources are scarce.

  5. Filthy Lucre: The Chemical Detection of Cocaine-Contaminated Currency.

    ERIC Educational Resources Information Center

    Acheson, Ed

    2001-01-01

    Discusses the problem of seizing cocaine-tainted money. Describes an experiment designed to determine what percentage of paper currency is contaminated with cocaine. Considers sampling, the analysis method, contamination, levels of cocaine in money and criminal activity, and the reliability of results. (SAH)

  6. Water contamination and environmental ecosystem in the Harlem River

    NASA Astrophysics Data System (ADS)

    Wang, J.

    2013-12-01

    Nutrients, bacteria, polychlorinated biphenyls (PCBs) and other contaminates have degraded water quality of the Harlem River. The Harlem River is a natural straight connected to the Hudson River and the East River, and it has been used for navigation and boating. Water samples have been collected and analyzed from 2011 to 2013. Phosphorus, ammonia, turbidity, fecal coliform, E.Coli., and enterococcus all exceed regulated levels for New York City waters. There is only one wastewater treatment plant (Wards Island WWTP) that serves this river. Combined sewer overflows (CSOs) discharge raw sewage into the river during storms in spring and summer. Commercial fishing is banned, .however, individuals still fish. While some fishermen catch and release, it is likely some fish are consumed, creating concern for the environmental health of the community along the river. Storm water runoff, CSOs, and wastewater effluents are major pollutant sources of PCB 11 (3,3' dichlorobiphenyl), nutrient and bacteria. Nutrients, bacteria levels and their spatial/temporal variations were analyzed, and PCB analysis is underway. This data is a critical first step towards improving the water quality and environmental ecosystem in the Harlem River.

  7. Biosupported Bimetallic Pd Au Nanocatalysts for Dechlorination of Environmental Contaminants

    SciTech Connect

    DeCorte, S.; Fitts, J.; Hennebel, T.; Sabbe, T.; Bliznuk, V.; Verschuere, S.; vanderLelie, D.; Verstraete, W.; Boon, N.

    2011-08-30

    Biologically produced monometallic palladium nanoparticles (bio-Pd) have been shown to catalyze the dehalogenation of environmental contaminants, but fail to efficiently catalyze the degradation of other important recalcitrant halogenated compounds. This study represents the first report of biologically produced bimetallic Pd/Au nanoparticle catalysts. The obtained catalysts were tested for the dechlorination of diclofenac and trichloroethylene. When aqueous bivalent Pd(II) and trivalent Au(III) ions were both added to concentrations of 50 mg L{sup -1} and reduced simultaneously by Shewanella oneidensis in the presence of H{sub 2}, the resulting cell-associated bimetallic nanoparticles (bio-Pd/Au) were able to dehalogenate 78% of the initially added diclofenac after 24 h; in comparison, no dehalogenation was observed using monometallic bio-Pd or bio-Au. Other catalyst-synthesis strategies did not show improved dehalogenation of TCE and diclofenac compared with bio-Pd. Synchrotron-based X-ray diffraction, (scanning) transmission electron microscopy and energy dispersive X-ray spectroscopy indicated that the simultaneous reduction of Pd and Au supported on cells of S. oneidensis resulted in the formation of a unique bimetallic crystalline structure. This study demonstrates that the catalytic activity and functionality of possibly environmentally more benign biosupported Pd-catalysts can be improved by coprecipitation with Au.

  8. A radiological and chemical investigation of the 7500 Area Contamination Site at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    SciTech Connect

    Williams, J.K.; Foley, R.D.; Tiner, P.F.; Hatmaker, T.L.; Uziel, M.S.; Swaja, R.E.

    1993-05-01

    A radiological and chemical investigation of the 7500 Area Contamination Site at Oak Ridge National Laboratory (ORNL) was conducted intermittently from February 1992 through May 1992. The investigation was performed by the Measurement Applications and Development Group of the Health and Safety Research Division of ORNL at the request of the US Department of Energy`s Oak Ridge Operations Office and the ORNL Environmental Restoration Program. Results of this investigation indicate that the source of radioactive contamination at the point of the contamination incident is from one of the underground abandoned lines. The contamination in soil is likely the result of residual contamination from years of waste transport and maintenance operations (e.g., replacement of degraded joints, upgrading or replacement of entire pipelines, and associated landscaping activities). However, because (1) there is currently an active LLW line positioned in the same subsurface trench with the abandoned lines and (2) the physical condition of the abandoned lines may be brittle, this inquiry could not determine which abandoned line was responsible for the subsurface contamination. Soil sampling at the location of the contamination incident and along the pipeline route was performed in a manner so as not to damage the active LLW line and abandoned lines. Recommendations for corrective actions are included.

  9. EFFECTS OF ENVIRONMENTAL CHEMICALS ON FETAL TESTES TESTOSTERONE PRODUCTION

    EPA Science Inventory

    Effects of Environmental Chemicals on Fetal Testes Testosterone Production

    Lambright, CS , Wilson, VS , Furr, J, Wolf, CJ, Noriega, N, Gray, LE, Jr.
    US EPA, ORD/NHEERL/RTD, RTP, NC

    Exposure of pregnant rodents to certain environmental chemicals during criti...

  10. SECOND NATIONAL REPORT ON HUMAN EXPOSURES TO ENVIRONMENTAL CHEMICALS

    EPA Science Inventory

    This report provides an ongoing assessment of the U.S. population's exposure to environmental chemicals using biomonitoring. The first National Report on Human Exposure to Environmental Chemicals (First Report) was issued in March 2001. This Second Report, released in January 200...

  11. ADAPTIONS OF WILD POPULATIONS OF THE ESTUARINE FISH FUNDULUS HETEROCLITUS TO PERSISTENT ENVIRONMENTAL CONTAMINANTS

    EPA Science Inventory

    Many aquatic species, including the estuarine fish Fundulus heteroclitus (mummichogs), adapt to local environmental conditions. We conducted studies to evaluate whether highly exposed populations of mummichogs adapt to toxic environmental contaminants. These fish populations are ...

  12. Synchrotron-based microanalytical techniques for the chemical speciation of metals and radionuclides in environmental samples

    SciTech Connect

    Bertsch, P.M.; Hunter, D.B.; Clark, S.B.

    1995-12-31

    A major obstacle in developing realistic environmental risk assessment or in designing environmentally sound, yet cost effective chemical and biological remediation strategies has been the ability to properly characterize the distribution and chemical speciation of a contaminant metal or radionuclide in an environmental sample or waste form. Synchrotron based X-ray fluorescence spectroscopy (SXRF) and X-ray absorption spectroscopy (XAS) are non-invasive techniques that can be used to examine the distribution and chemical speciation of elements (Z {ge} 20) in moist heterogeneous samples under ambient temperature and pressure. Using a dedicated micro-probe beam line (X-26A) at the National Synchrotron Light Source, Brookhaven National Lab, we have conducted spatially resolved XAS studies on a variety of environmental samples and on samples produced in waste isolation and processing activities. Spatially resolved SXRF spectroscopy has been used to generate elemental distribution maps on a 5 {mu}m scale, providing information on elemental distributions and associations. In addition, spatially resolved X-ray absorption near edge structure (XANES) spectroscopy has provided detailed information on the oxidation states of U, Cr, Se, and other metals and metalloids in contaminated soils, biological samples, and in waste forms on regions as small as 40 Pin, with minimal sample manipulation. Furthermore, qualitative information on bonding environments of many of these contaminants has been deduced based upon the {open_quote}fingerprint{close_quote} or multiple scattering regions of the XANES spectra coupled with the elemental distribution maps generated by SXRF spectroscopy.

  13. Environmental chemical mutagens and genetic risks: Lessons from radiation genetics

    SciTech Connect

    Sankaranarayanan, K.

    1996-12-31

    The last three decades have witnessed substantial progress in the development and use of a variety of in vitro and in vivo assay systems for the testing of environmental chemicals which may pose a mutagenic hazard to humans. This is also true of basic studies in chemical mutagenesis on mechanisms, DNA repair, molecular dosimetry, structure-activity relationships, etc. However, the field of quantitative evaluation of genetic risks of environmental chemicals to humans is still in it infancy. This commentary addresses the question of how our experience in estimating genetic risks of exposure to ionizing radiation can be helpful in similar endeavors with environmental chemical mutagens. 24 refs., 3 tabs.

  14. Caging techniques for field exposures of fish to chemical contaminants.

    PubMed

    Oikari, Aimo

    2006-07-20

    The article reviews current state-of-the-art to conduct fish caging as an assessment and monitoring technique in aquatic toxicology. A multitude of scientific, practical and management factors influence and may restrict how field research is carried out. For many purposes the advantages of transplant fish caging outweigh the alternative methodologies of impact studies of xenobiotics. However, besides mortality, virtually no study has evaluated the physiological consequences of caging fish. It is not known how caging itself affects the responses of fishes to chemical pollution. The used caging densities are commonly too high. However, with the aid of variables describing physiological stress it is possible to evaluate stress-free caging for a given species, cage design, and experimental settings. Comparison of fish in cages to free-living counterparts or to fish in confirmed stress-free conditions are appropriate ways to evaluate the status of fishes used as references. An international harmonization and standardization of methods would widen the use of transplant caging of fish as a tool for environmental research and assessment. PMID:16750578

  15. Pilot-scale incineration of contaminated soil from the chemical insecticide corporation superfund site. Final report

    SciTech Connect

    Siag, A.; Fournier, D.J.; Waterland, L.R.

    1993-02-01

    An incineration test program was conducted at the U.S. Environmental Protection Agency's Incinerator Research Facility to evaluate the potential of incineration as an option to treat contaminated soils at the Chemical Insecticide Corporation Site. The test data show that: The organochlorine pesticides were destroyed to non-detectable quantities in the ash, the state-of-the-art scrubber removed arsenic to the 99.95% level, lime addition did not improve the arsenic removal efficiency, toxicity characteristic leaching procedure (TCLP) values for ash metals varied, lime addition reduced TCLP leachability of metals, particulate and HCl levels were within accepted limits. Incineration data that can be used for other purposes was also collected for the soil tested.

  16. The importance of evaluating the physicochemical and toxicological properties of a contaminant for remediating environments affected by chemical incidents.

    PubMed

    Wyke, S; Pea-Fernndez, A; Brooke, N; Duarte-Davidson, R

    2014-11-01

    In the event of a major chemical incident or accident, appropriate tools and technical guidance need to be available to ensure that a robust approach can be adopted for developing a remediation strategy. Remediation and restoration strategies implemented in the aftermath of a chemical incident are a particular concern for public health. As a result an innovative methodology has been developed to help design an effective recovery strategy in the aftermath of a chemical incident that has been developed; the UK Recovery Handbook for Chemical Incidents (UKRHCI). The handbook consists of a six-step decision framework and the use of decision trees specifically designed for three different environments: food production systems, inhabited areas and water environments. It also provides a compendium of evidence-based recovery options (techniques or methods for remediation) that should be selected in relation to their efficacy for removing contaminants from the environment. Selection of effective recovery options in this decision framework involves evaluating the physicochemical and toxicological properties of the chemical(s) involved. Thus, the chemical handbook includes a series of tables with relevant physicochemical and toxicological properties that should be assessed in function of the environment affected. It is essential that the physicochemical properties of a chemical are evaluated and interpreted correctly during the development of a remedial plan in the aftermath of a chemical incident to ensure an effective remedial response. This paper presents a general overview of the key physicochemical and toxicological properties of chemicals that should be evaluated when developing a recovery strategy. Information on how physicochemical properties have impacted on previous remedial responses reported in the literature is also discussed and a number of challenges for remediation are highlighted to include the need to develop novel approaches to remediate sites contaminated by mixtures of chemicals as well as methods for interpreting chemical reactions in different environmental matrices to include how climate change may affect the speciation and mobility of chemicals in the environment. PMID:24874001

  17. Environmental analysis of the chemical release module. [space shuttle payload

    NASA Technical Reports Server (NTRS)

    Heppner, J. P.; Dubin, M.

    1980-01-01

    The environmental analysis of the Chemical Release Module (a free flying spacecraft deployed from the space shuttle to perform chemical release experiments) is reviewed. Considerations of possible effects of the injectants on human health, ionosphere, weather, ground based optical astronomical observations, and satellite operations are included. It is concluded that no deleterious environmental effects of widespread or long lasting nature are anticipated from chemical releases in the upper atmosphere of the type indicated for the program.

  18. CHEMICAL-SPECIFIC PARAMETERS FOR TOXICITY CHARACTERISTIC CONTAMINANTS

    EPA Science Inventory

    Acid, base, and neutral hydrolysis rate constants and partition coefficients are given for 44 toxicity characteristic contaminants. Both calculated and laboratory-determined octanol/water partition coefficient (Kow) and organic-carbon-normalized partition coefficient (Koc) values...

  19. EVALUATING AND DESIGNING CHEMICAL PROCESSES FOR ENVIRONMENTAL SUSTAINABILITY

    EPA Science Inventory

    Chemicals and chemical processes are at the heart of most environmental problems. This isn't surprising since chemicals make up all of the products we use in our lives. The common use of cjhemicals makes them of high interest for systems analysis, particularly because of environ...

  20. Overview of Chemicals of Emerging Concern

    EPA Science Inventory

    Contaminants of emerging concern or environmental emerging contaminants, are chemicals, products and materials that are detected with increasing frequency in all environmental media including surface, ground water and drinking water. Examples of these contaminants include pharmac...

  1. Environmental contamination with Mycobacterium avium subsp. paratuberculosis in endemically infected dairy herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental contamination with Mycobacterium avium subsp. paratuberculosis (MAP) is thought to be the primary source of infection for dairy cattle. The exact link between fecal shedding of MAP by individual cows and environmental contamination levels at the herd level was explored with a cross-se...

  2. Effectiveness of an antimicrobial polymer to decrease contamination of environmental surfaces in the clinical setting.

    PubMed

    Thom, Kerri A; Standiford, Harold C; Johnson, J Kristie; Hanna, Nader; Furuno, Jon P

    2014-08-01

    We performed a real-world, controlled intervention to investigate use of an antimicrobial surface polymer, MSDS Poly, on environmental contamination. Pathogenic bacteria were identified in 18 (90%) of 20 observations in treated rooms and 19 (83%) of 23 observations in untreated rooms (P = .67). MSDS Poly had no significant effect on environmental contamination. PMID:25026625

  3. Effectiveness of an Antimicrobial Polymer to Decrease Contamination of Environmental Surfaces in the Clinical Setting

    PubMed Central

    Thom, Kerri A.; Standiford, Harold C.; Johnson, J. Kristie; Hanna, Nader; Furuno, Jon P.

    2015-01-01

    We performed a real-world, controlled intervention to investigate use of an antimicrobial surface polymer, MSDS Poly, on environmental contamination. Pathogenic bacteria were identified in 90% (18/20) of treated-room-observations and 83% (19/23) of the untreated-room-observations (p=0.67). MSDS Poly had no significant effect on environmental contamination. PMID:25026625

  4. Environmental analysis of endocrine disrupting effects from hydrocarbon contaminants in the ecosystem. 1998 annual progress report

    SciTech Connect

    McLachlan, J.

    1998-06-01

    'The objective of this project is to determine how environmental contaminants, namely hydrocarbons, can act as hormones or anti-hormones (i.e., environmental hormones) in different species present in aquatic ecosystems. Species of particular focus are those which can serve as sentinel species (e.g., amphibians) and, thus, provide early warning signals for more widespread impacts on an ecosystem and its wildlife and human inhabitants. This reports the progress of 1.5 years of a three-year grant awarded to the Tulane/Xavier Center for Bioenvironmental Research (CBR). A growing body of evidence suggests that chemicals in the environment can disrupt the endocrine system of animals (i.e., wildlife and humans) and adversely impact the development of these species. Because of the multitude of known endocrine-disrupting chemicals and the numerous industrial and government sectors producing these chemicals, almost every federal agency has initiated research on the endocrine effects of chemicals relevant to their operations. This study represents the Department of Energy (DOE) Basic Energy Sciences'' only research on the impacts of endocrine-disrupting chemicals. The activities employed by this project to determine these impacts include development of biotechnology screens (in vitro), animal screens (in vivo), and other analyses of aquatic ecosystem biomarkers of exposure. The results from this study can elucidate how chemicals in the environment, including those from DOE activities, can signal (and alter) the development of a number of species in aquatic ecosystems. These signals can have detrimental impacts not only on an organismal level, but also on community, population, and entire ecosystem levels, including humans.'

  5. ANALYTICAL METHODS DEVELOPMENT FOR EMERGING CHEMICAL CONTAMINANTS AND FOR UNREGULATED CONTAMINANT MONITORING AND CCL

    EPA Science Inventory

    The 1996 amendments to the Safe Drinking Water Act (SDWA) required EPA to establish a Contaminant Candidate List (CCL), that contains a list of drinking water contaminants that the Agency will consider for future regulation. EPA must make a regulatory determination on a minimum ...

  6. Assessing contaminant sensitivity of endangered and threatened aquatic species: Part I. Acute toxicity of five chemicals

    USGS Publications Warehouse

    Dwyer, F.J.; Mayer, F.L.; Sappington, L.C.; Buckler, D.R.; Bridges, C.M.; Greer, I.E.; Hardesty, D.K.; Henke, C.E.; Ingersoll, C.G.; Kunz, J.L.; Whites, D.W.; Augspurger, T.; Mount, D.R.; Hattala, K.; Neuderfer, G.N.

    2005-01-01

    Assessment of contaminant impacts to federally identified endangered, threatened and candidate, and state-identified endangered species (collectively referred to as "listed" species) requires understanding of a species' sensitivities to particular chemicals. The most direct approach would be to determine the sensitivity of a listed species to a particular contaminant or perturbation. An indirect approach for aquatic species would be application of toxicity data obtained from standard test procedures and species commonly used in laboratory toxicity tests. Common test species (fathead minnow, Pimephales promelas; sheepshead minnow, Cyprinodon variegatus; and rainbow trout, Oncorhynchus mykiss) and 17 listed or closely related species were tested in acute 96-hour water exposures with five chemicals (carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin) representing a broad range of toxic modes of action. No single species was the most sensitive to all chemicals. For the three standard test species evaluated, the rainbow trout was more sensitive than either the fathead minnow or sheepshead minnow and was equal to or more sensitive than listed and related species 81% of the time. To estimate an LC50 for a listed species, a factor of 0.63 can be applied to the geometric mean LC50 of rainbow trout toxicity data, and more conservative factors can be determined using variance estimates (0.46 based on 1 SD of the mean and 0.33 based on 2 SD of the mean). Additionally, a low- or no-acute effect concentration can be estimated by multiplying the respective LC50 by a factor of approximately 0.56, which supports the United States Environmental Protection Agency approach of multiplying the final acute value by 0.5 (division by 2). When captive or locally abundant populations of listed fish are available, consideration should be given to direct testing. When direct toxicity testing cannot be performed, approaches for developing protective measures using common test species toxicity data are available. ?? 2005 Springer Science+Business Media, Inc.

  7. Chemical contamination of the East River (Dongjiang) and its implication on sustainable development in the Pearl River Delta.

    PubMed

    Ho, K C; Hui, K C

    2001-05-01

    A recent survey reveals that water quality and river sediments of Dongjiang (the East River) have been mildly contaminated by heavy metals and organic chemicals, such as copper, lead, PCBs, PAHs and HCHs. According to photogrammertic surveys, the sources of contamination are closely related to human activities, such as domestic and industrial discharges, agricultural chemical applications and soil erosion due to deforestation. The level of water and sediment contamination is most serious at the mid-river section near the urban of Weizhou. Due to natural dilution and diffusion, the levels of contamination are slightly decreased at the medium low section of the River near Qiaotou and Matan. Nevertheless, the levels of contamination increase again in the lower river section near Shenzhen, which is a highly developed economic zone. Since Dongjiang is the major source of potable water supply for Hong Kong (nearly 80% of potable water of Hong Kong is abstracted from Dongjiang) and the other parts of the Pearl River Delta (PRD), such organic and inorganic pollution merit concern. Ironically, most of the industrial and commercial activities in the watershed of Dongjiang are business investments of Hong Kong citizens. Cross-border environmental efforts should be enhanced with collaboration of different jurisdictions to achieve targets of regional sustainability. PMID:11392743

  8. Cumulative index to chemicals and to common and scientific names of species listed in Contaminant Hazard Reviews 1 through 34

    USGS Publications Warehouse

    Eisler, Ronald, (Edited By)

    1999-01-01

    The Contaminant Hazard Review (CHR) series--sponsored by the U.S. Geological Survey, Patuxent Wildlife Research Center--synthesizes ecotoxicological data for selected environmental contaminants, with emphasis on hazards to native species of flora and fauna. From 1985 through 1998, 34 reviews were published in various report series of the U.S. Department of the Interior on agricultural pesticides (acrolein, atrazine, carbofuran, chlordane, chlorpyrifos, diazinon, diflubenzuron, famphur, fenvalerate, mirex, paraquat, toxaphene), metals and metalloids (arsenic, boron, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, silver, tin, zinc), mammalian biocides (sodium monofluoroacetate), organic industrial and municipal wastes (dioxins, pentachlorophenol, polycyclic aromatic hydrocarbons, polychlorinated biphenyls), minin wastes (cyanide), and ionizing radiations. This current report is a cumulative index to the common and scientific names of all biological species listed in the first 34 reports in the CHR series, with individual species cross-referenced with contaminant hazard review and corresponding page numbers. A similar index for chemicals is included.

  9. Bages-Sigean and Canet-St Nazaire lagoons (France): physico-chemical characteristics and contaminant concentrations (Cu, Cd, PCBs and PBDEs) as environmental quality of water and sediment.

    PubMed

    Vouv, Florence; Buscail, Roselyne; Aubert, Dominique; Labadie, Pierre; Chevreuil, Marc; Canal, Christophe; Desmousseaux, Marion; Alliot, Fabrice; Amilhat, Elsa; Faliex, Elisabeth; Paris-Palacios, Sverine; Biagianti-Risbourg, Sylvie

    2014-02-01

    Environmental characteristics in water and sediments of two contrasted coastal Mediterranean lagoons, Bages-Sigean and Canet-St Nazaire, were measured over a three season survey. The urban pollution (treatment plant discharges) is very important in Canet-St Nazaire lagoon reflecting untreated sewages, while in Bages-Sigean, the northern part appears more impacted due to larger anthropogenic inputs. Dissolved Cd concentrations are on the whole similar in both lagoons, whereas Cu concentrations are by far higher in lagoon Canet-St Nazaire. Cu concentrations appear to be highly dependent on dissolved organic carbon whereas salinity seems to control Cd variations. Concerning the sediments, the confined northern part of lagoon Bages-Sigean shows organic carbon and total nitrogen enrichment whereas lipid concentrations are much higher in the Canet-St Nazaire lagoon. Cu complexation seems to be strongly related to organic matter as evidenced by the two significant positive relationships, on one hand between Cu and organic carbon, and on the other hand, between Cu and lipids. On the contrary, Cd concentrations appear to be mainly controlled by carbonates. PCBs and PBDEs were detected only in sediments and show relatively low concentrations compared to similar lagoon environments. Regarding the sediment quality guidelines, Cd, Cu and PCBs in both lagoons did not exceed any Probable Effect Concentration (PEC). PMID:24174314

  10. Vitellogenin as a potential biomarker for environmental contaminants

    SciTech Connect

    Denslow, N.D.; Folmar, L.C.; Sullivan, C.V.

    1994-12-31

    The authors have recently obtained N-terminal amino acid sequences for the egg protein vitellogenin (Vtg) from phylogenetically diverse teleost fish ranging from rainbow trout to the striped bass. Using the striped bass sequence as a template, the other teleost fish showed at least an 87% identity through the region of amino acids 7--20. The amino acid sequence was not as well conserved for other fishes; white sturgeon (60%) and brook lamprey (47%), the clawed frog Xenopus (47--60%) or the domestic chicken (40%). The authors synthesized a consensus peptide to this highly conserved region and have raised a polygonal antibody from rabbit. This antibody shows wide cross-reactivity to Vtg from many species of teleost fish. The authors have found that serum Vtg levels are elevated in both male and female brown bullheads with liver tumors from an area contaminated with polycyclic aromatic hydrocarbons. Serum levels of Vtg were also elevated in rainbow trout with liver tumors induced with aflatoxin B-1. The authors also describe an in-vitro system of plated hepatocytes to screen for estrogenic and antiestrogenic xenobiotic chemicals in the environment and using Vtg as a screening tool to establish structure-activity relationships for reproductive failure in female fish.

  11. Embryotoxicity and teratogenicity of environmental contaminants to bird eggs

    USGS Publications Warehouse

    Hoffman, D.J.

    1990-01-01

    First awareness that direct topical application of xenobiotics to bird eggs could be harmful to avian development dates back to the turn of the century. The most widely documented evidence of embryotoxicity following direct exposure comes from petroleum contaminant studies, conducted with at least 10 different avian species. Many petroleum crude oils, refined oils, and waste oils are embryotoxic and moderately teratogenic to different species; LD50s are often less than 5 iL of oil per egg. Toxicity is generally dependent upon the PAH concentration and composition (presence of higher weight PAHs). Five of seven industrial effluents caused significant reduction of embryonic growth in mallards following brief immersion of the eggs. Of the insecticides, organophosphates have been the most widely studied with respect to potential for direct embryotoxicity and teratogenicity following spraying or immersion of eggs. Phenoxy herbicides including 2,4-D and 2,4,5-T have been the most widely studied class of herbicides with respect to potential embryotoxicity of spray application. However, more recent evaluations have indicated that this is not the most toxic class of herbicides. Paraquat was found to be highly toxic in at least three species. Herbicides with LC50s that occurred at ten times the field level of application or less for mallard embryos included bromoxynil with MCPA, methyldiclofop, paraquat, prometon, propanil, and trifluralin. Of different gaseous and particulate air pollutants, ozone and particulates rich in PAH content appeared to be potentially embryotoxic, based on laboratory studies. Environmental contaminants in all classes reviewed have been shown to cause physiological and biochemical disturbances in embryos or hatchlings indicative of contaminant exposure, organ damage, or delayed development. Residue studies have shown the presence of DDT, 2,4-D, 2,4,5-T, decamethrin, petroleum hydrocarbons, and methylmercury after direct exposure of eggs. Ability of xenobiotics to pass across the shell and its membranes as well as embryo uptake appear to be dependent both on the compound and the vehicle. Pesticides in aliphatic (nontoxic oil) vehicle were generally more toxic than ones in aqueous emulsion due to better penetration. Field studies have documented the embryotoxicity of petroleum following transfer from plumage of adult birds to their eggs. Few attempts to measure effects of spraying pesticides near bird nests have been documented. However, application of pesticide mixtures including organophosphate insecticides and fungicides to orchards resulted in embryo ic mortality in mourning dove nests. Future studies are needed to focus on field exposures in multiple species. Comparative laboratory studies are needed taking into consideration shell thickness and porosity to determine whether species such as passerines may be more sensitive. Additive and possibly synergistic effects may occur where xenobiotics may be only slightly to moderately toxic alone. Therefore, further studies examining the effects of pesticides routinely applied in combinations of two or more are needed, as are air pollution studies examining multiple contaminants and species.

  12. Environmental contaminant exposure data and monitoring priorities for wild terrestrial vertebrates at national parks in coastal and estuarine habitat

    USGS Publications Warehouse

    Rattner, B.A.; Ackerson, B.K.; Eisenreich, K.M.; McKernan, M.A.

    2006-01-01

    The Biomonitoring of Environmental Status and Trends (BEST) Project of the U.S. Geological Survey (USGS) assesses the exposure and effects of environmental contaminants on select species and habitats in the United States. One of the many BEST Project activities entails the development of decision-support tools to assist in the identification of chemical threats to species and lands under the stewardship of the Department of the Interior. Although there are many ecotoxicological monitoring programs that focus on aquatic species and habitats, there are currently no large-scale efforts that are focused on terrestrial vertebrates in the United States. Nonetheless, organochlorine contaminants, metals, and new pollutants continue to pose hazards to terrestrial vertebrates at many spatial scales (ranging from small hazardous-waste-site point sources to entire watersheds). To evaluate and prioritize pollutant hazards for terrestrial vertebrates, a ?Contaminant Exposure and EffectsTerrestrial Vertebrates? (CEE-TV) database (www.pwrc.usgs.gov/contaminants-online) was developed. The CEE-TV database has been used to conduct simple searches for exposure and biological effects information for a given species or location, identification of temporal contaminant exposure trends, information gap analyses for national wildlife refuge and national park units, and ranking of terrestrial vertebrate ecotoxicological information needs based on data density and water quality problems. Despite widespread concerns about environmental contamination, during the past decade only about one-half of the coastal National Park units appear to have terrestrial vertebrate ecotoxicological data. Based upon known environmental contaminant hazards, it is recommended that regionalized monitoring programs or efforts focused on lands managed by the Department of the Interior should be undertaken to prevent serious natural resource problems.

  13. Forms and prevalence of intersexuality and effects of environmental contaminants on sexuality in cricket frogs (Acris crepitans).

    PubMed Central

    Reeder, A L; Foley, G L; Nichols, D K; Hansen, L G; Wikoff, B; Faeh, S; Eisold, J; Wheeler, M B; Warner, R; Murphy, J E; Beasley, V R

    1998-01-01

    Cricket frogs (Acris crepitans) from several different sites in Illinois were collected to assess the effects of environmental contamination on the prevalence of intersex gonads. Of 341 frogs collected in 1993, 1994, and 1995, 2.7% were intersex individuals. There was no statistically significant relationship between the chemical compounds detected and cricket frog intersexuality. However, there was an association approaching significance (p = 0.07) between the detection of atrazine and intersex individuals. A comparison of reference sites with sites that had point polychlorinated biphenyl (PCB) and polychlorinated dibenzofuran (PCDF) contamination revealed a significant relationship between sex-ratio reversal and contamination with PCBs and PCDFs. The sex ratio of juvenile frogs studied from three sites with PCB and PCDF point contamination favored males over females, which was the opposite of the sex ratio in control ponds (p = 0.0007). The statistically significant correlation between organochlorine contamination and sex-ratio reversal suggests PCBs and PCDFs can influence cricket frog sexual differentiation. The current study suggests that in cricket frogs, sex ratios and the prevalence of intersex gonads are altered by environmental contamination. Images Figure 1 Figure 2 PMID:9647894

  14. Organic contaminants in Great Lakes tributaries: Identification of watersheds and chemicals of greatest concern

    EPA Science Inventory

    Trace organic contaminant concentrations in some Great Lakes tributaries indicate potential for adverse effects on aquatic organisms. Chemicals used in agriculture, industry, and households enter surface waters via variety of sources, including urban and agricultural runoff, sewa...

  15. Uncertainties in human health risk assessment of environmental contaminants: A review and perspective.

    PubMed

    Dong, Zhaomin; Liu, Yanju; Duan, Luchun; Bekele, Dawit; Naidu, Ravi

    2015-12-01

    Addressing uncertainties in human health risk assessment is a critical issue when evaluating the effects of contaminants on public health. A range of uncertainties exist through the source-to-outcome continuum, including exposure assessment, hazard and risk characterisation. While various strategies have been applied to characterising uncertainty, classical approaches largely rely on how to maximise the available resources. Expert judgement, defaults and tools for characterising quantitative uncertainty attempt to fill the gap between data and regulation requirements. The experiences of researching 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) illustrated uncertainty sources and how to maximise available information to determine uncertainties, and thereby provide an 'adequate' protection to contaminant exposure. As regulatory requirements and recurring issues increase, the assessment of complex scenarios involving a large number of chemicals requires more sophisticated tools. Recent advances in exposure and toxicology science provide a large data set for environmental contaminants and public health. In particular, biomonitoring information, in vitro data streams and computational toxicology are the crucial factors in the NexGen risk assessment, as well as uncertainties minimisation. Although in this review we cannot yet predict how the exposure science and modern toxicology will develop in the long-term, current techniques from emerging science can be integrated to improve decision-making. PMID:26386465

  16. Chemical Fingerprinting of Materials Developed Due to Environmental Issues

    NASA Technical Reports Server (NTRS)

    Smith, Doris A.; McCool, A. (Technical Monitor)

    2000-01-01

    Instrumental chemical analysis methods are developed and used to chemically fingerprint new and modified External Tank materials made necessary by changing environmental requirements. Chemical fingerprinting can detect and diagnose variations in material composition. To chemically characterize each material, fingerprint methods are selected from an extensive toolbox based on the material's chemistry and the ability of the specific methods to detect the material's critical ingredients. Fingerprint methods have been developed for a variety of materials including Thermal Protection System foams, adhesives, primers, and composites.

  17. A PILOT STUDY TO COMPARE MICROBIAL AND CHEMICAL INDICATORS OF HUMAN FECAL CONTAMINATION IN WATER

    EPA Science Inventory

    Limitations exist in applying traditional microbial methods for the detection of human fecal contamination of water. A pilot study was undertaken to compare the microbial and chemical indicators of human fecal contamination of water. Sixty-four water samples were collected in O...

  18. TRANSPORT OF ORGANIC CONTAMINANTS IN GROUNDWATER: DISTRIBUTION AND FATE OF CHEMICALS IN SAND AND GRAVEL AQUIFERS

    EPA Science Inventory

    The state-of-knowledge of the physical, chemical, and biological processes that are thought to affect organic contaminants in ground water are reviewed. The discussion is confined to horizontal flow in uniform sand and gravel aquifers. General principles governing contaminant tra...

  19. CHEMICAL CONTAMINATION AND TOXICITY ASSOCIATED WITH A COASTAL GOLF COURSE COMPLEX

    EPA Science Inventory

    The increasing density of golf courses represents a potential source of contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to compare the concentrations of contaminants and toxicities of sedime...

  20. Environmentally stable chemically amplified positive resist containing vinyllactam terpolymers

    NASA Astrophysics Data System (ADS)

    Bok, Cheol-Kyu; Koh, Cha-Won; Jung, Min-Ho; Baik, Ki-Ho; Kim, Jin-Baek; Cheong, Jong-Ho

    1997-07-01

    In this paper we report here on lithographic performance of high resolution, environmentally stable and aqueous base developable positive tone resist for DUV lithography. There have been a lot of efforts to prevent the resist from suffering from the deactivation of acid during the delay time between exposure and post exposure bake (PEB). The new design of matrix resin containing amide functional group has advantages over current lithographic techniques. The effects of amide functional group as a basic additive in a chemically amplified resist was investigated. A new class of matrix resin containing amide functional group, poly(hydroxystyrene-co-t- butyl acrylate-co-3-(t-butoxycarbonyl)-1-vinyl-2-caprolactam), was developed. It showed 0.20 micrometer lines/spaces patterns of this resist using KrF excimer stepper (NA 0.55, partial coherence factor 0.55) with an exposure dose of 25 mJ/cm2. This resist showed no change of pattern profile after 2 hours post exposure delay in which ammonia concentration is 5 ppb. 3-(t-butoxycarbonyl)-1-vinyl-2-caprolatam (BCVC) unit as a basic additive can not only solve amine contamination effectively, but also improve the resolution of the resist. BCVC unit reduces the diffusion of acid and it results in sharp contrast at the interface between the exposed and unexposed areas. Therefore, adding BCVC unit in matrix resin leads to the stabilization of the pattern profile and higher resolution.

  1. Contamination from electrically conductive silicone tubing during aerosol chemical analysis

    SciTech Connect

    Yu, Yong; Alexander, M. L.; Perraud, Veronique; Bruns, Emily; Johnson, Stan; Ezell, Michael J.; Finlayson-Pitts, Barbara J.

    2009-06-01

    Electrically conductive silicone tubing is used to minimize losses in sampling lines during the analysis of airborne particle size distributions and number concentrations. We report contamination from this tubing using gas chromatography-mass spectrometry (GC-MS) of filter-collected samples as well as by particle mass spectrometry. Comparison of electrically conductive silicone and stainless steel tubing showed elevated siloxanes only for the silicone tubing. The extent of contamination increased with length of tubing to which the sample was exposed, and decreased with increasing relative humidity.

  2. [Chemical contamination of the child: bioacumulation and potential effects].

    PubMed

    del Río Paredes, Sara

    2005-01-01

    In early 2003, Greenpeace exposed the presence of persistent, bioaccumulative chemical pollutants in samples of house dust taken from homes across europe. Greenpeace further researches revealed that these same chemicals can be found in many daily consumer products. This report completes the loop by illustrating two disturbing developments. Firstly, that many of the same chemicals used routinely in consumer products and present in house dust, are also present in the human body, including in prenatal and newborn children. Secondly, that these chemicals are likely to be having a detrimental effect on the health of children and the human population at large. Dorey draws together the available evidence that illustrates how and why prenatal and newly born children are particularly at risk from chemical pollutants. The evidence presented here, from academics, governments and international institutions is not easily dismissed, contributing as it does to a growing bank of international research that reinforces the conclusion of this report--that current chemical legislation is failing to protect children from a harmful chemical assault that begins from a child's conception. The study focuses on seven key chemicals: alkylphenols, bisphenol A, brominated flame retardants, organotins, phthalates, chlorinated paraffins and artificial musks, and demonstrates: the presence of these substances in children, the ways in which children are particularly exposed, how this increased exposure increases the potential for detrimental health impacts, the different illnesses and diseases that are now being linked to this chemical exposure and the specific health impacts of the key chemicals listed above. PMID:15913056

  3. Global styrene oligomers monitoring as new chemical contamination from polystyrene plastic marine pollution.

    PubMed

    Kwon, Bum Gun; Koizumi, Koshiro; Chung, Seon-Yong; Kodera, Yoichi; Kim, Jong-Oh; Saido, Katsuhiko

    2015-12-30

    Polystyrene (PS) plastic marine pollution is an environmental concern. However, a reliable and objective assessment of the scope of this problem, which can lead to persistent organic contaminants, has yet to be performed. Here, we show that anthropogenic styrene oligomers (SOs), a possible indicator of PS pollution in the ocean, are found globally at concentrations that are higher than those expected based on the stability of PS. SOs appear to persist to varying degrees in the seawater and sand samples collected from beaches around the world. The most persistent forms are styrene monomer, styrene dimer, and styrene trimer. Sand samples from beaches, which are commonly recreation sites, are particularly polluted with these high SOs concentrations. This finding is of interest from both scientific and public perspectives because SOs may pose potential long-term risks to the environment in combination with other endocrine disrupting chemicals. From SOs monitoring results, this study proposes a flow diagram for SOs leaching from PS cycle. Using this flow diagram, we conclude that SOs are global contaminants in sandy beaches around the world due to their broad spatial distribution. PMID:26218303

  4. Sublethal health effects in laboratory rodents from environmentally relevant exposures to oil sands contaminants.

    PubMed

    Rodrguez-Estival, Jaime; North, Michelle A; Smits, Judit E G

    2015-12-01

    Increasing activity of oil sands extraction and processing in northern Alberta is marked by ongoing controversy about the nature and extent of associated environmental impacts. Bitumen contains a mixture of toxic chemicals, including metals and residual polycyclic aromatic hydrocarbons (PAHs), whose release into the environment poses a distinct risk to the surrounding environment, plus wildlife and human health. In the present study, the authors evaluated several subclinical biomarkers of exposure and effect to mixtures of metals (Pb, Cd, and Hg) and/or PAHs (3 alkylated forms) at environmentally relevant concentrations (100-fold and 10-fold higher than the maximum dissolved concentrations found in snow, to simulate a worst-case scenario), using laboratory mice as a model for future studies of small mammals in the wild. Both metals and alkyl-PAHs exposure were associated with 1) increased relative liver, kidney, and spleen size; 2) alterations in the homeostasis of the antioxidant vitamins A and E in liver; and 3) compromised glutathione redox status in testes, with results also indicating synergistic interactions from co-exposure. The combination of morphometric and oxidative stress biomarkers provide reliable and sensitive measures of the response to contaminant exposure in a mammalian model, suggesting associated physiological costs. Based on the present experimental study, the authors propose that wild small mammals will prove to be valuable sentinel species reflecting sublethal health effects from oil sands-related contaminants. The present study's results also present a basis for the interpretation of future field data. PMID:26139097

  5. POPTOX: Population-level responses of an amphipod to contaminated marine sediments and other environmental stresses

    SciTech Connect

    DeWitt, T.H.

    1994-12-31

    Experimental measurements of population-level responses are useful to environmental management in two ways: (1) to estimate the fitness of populations in an ecological-risk study, and (2) to evaluate the ecological relevance of shorter-term acute and chronic toxicity tests that use the same test species. An experimental system was developed for modeling the population-level responses of the burrowing, estuarine amphipod, Leptocheirus plumulosus, to environmental stresses, including chemical contamination. Replicate cohorts of newborn amphipods were exposed to natural and anthropogenic (PAH-contaminated sediment) stresses under static-renewal conditions over periods varying up to their full life-span. The amphipods were periodically removed from the sediment, censused, measured, and returned alive to the exposure chamber; the resulting life-history data were used to develop age-based, matrix-algebraic, population-projection models. Preliminary experiments revealed that an exposure period of 12 weeks with a sampling frequency of 2 weeks was sufficient to model the population dynamics of this amphipod. This experimental system may also be,used to study the interaction between anthropogenic stresses and ecological stresses under controlled and long-term exposures.

  6. Impacts of Environmental Nanoparticles on Chemical, Biological and Hydrological Processes in Terrestrial Ecosystems

    SciTech Connect

    Qafoku, Nikolla

    2012-01-01

    This chapter provides insights on nanoparticle (NP) influence or control on the extent and timescales of single or coupled physical, chemical, biological and hydrological reactions and processes that occur in terrestrial ecosystems. Examples taken from the literature that show how terrestrial NPs may determine the fate of the aqueous and sorbed (adsorbed or precipitated) chemical species of nutrients and contaminants, are also included in this chapter. Specifically, in the first section, chapter objectives, term definitions and discussions on size-dependent properties, the origin and occurrence of NP in terrestrial ecosystems and NP toxicity, are included. In the second section, the topic of the binary interactions of NPs of different sizes, shapes, concentrations and ages with the soil solution chemical species is covered, focusing on NP formation, stability, aggregation, ability to serve as sorbents, or surface-mediated precipitation catalysts, or electron donors and acceptors. In the third section, aspects of the interactions in the ternary systems composed of environmental NP, nutrient/contaminant chemical species, and the soil/sediment matrix are discussed, focusing on the inhibitory and catalytic effects of environmental NP on nutrient/contaminant advective mobility and mass transfer, adsorption and desorption, dissolution and precipitation and redox reactions that occur in terrestrial ecosystems. These three review sections are followed by a short summary of future research needs and directions, the acknowledgements, the list of the references, and the figures.

  7. Computational Toxicology: Application in Environmental Chemicals

    EPA Science Inventory

    This chapter provides an overview of computational models that describe various aspects of the source-to-health effect continuum. Fate and transport models describe the release, transportation, and transformation of chemicals from sources of emission throughout the general envir...

  8. Environmental mercury contamination in China: sources and impacts.

    PubMed

    Zhang, L; Wong, M H

    2007-01-01

    This review article focused on the current status of mercury (Hg) contamination in different ecological compartments in China, and their possible environmental and health impacts, focusing on some major cities. Mercury emission from non-ferrous metals smelting (especially zinc smelting), coal combustion and miscellaneous activities (of which battery and fluorescent lamp production and cement production are the largest), contributed about 45%, 38% and 17%, respectively, to the total Hg emission based on the data of 1999. Mercury contamination is widespread in different ecological compartments such as atmosphere, soil and water. There is evidence showing bioaccumulation and biomagnification of Hg in aquatic food chains, with higher concentrations detected in carnivorous fish. In terms of human exposure to Hg, fish consumption is the major exposure pathway for residents living in coastal cities such as Hong Kong, but inhalation may be another major source, affecting human health in areas with severe atmospheric Hg, such as Guiyang City (Guizhou Province). The first case study indicated that after closure of the acetic acid plant 20 years at Songyuan City (Jilin Province), 16.7% of residents' hair still contained Hg concentration in excess of 1 mg/kg (the reference dosage value, RfD set by USEPA). The second case study indicated that the male residents of Hong Kong who consumed more than four or more meals of fish per week tended to contain higher Hg in their hair, which was linked to their subfertility. There is also increasing evidence showing that skin disorders and autism in Hong Kong children are related to their high Hg body loadings (hair, blood and urine), through prenatal methyl Hg exposure. There seems to be an urgent need to identify the sources of Hg, speciation and concentrations in different ecological compartments, which may lead to high body loadings in human beings. Adverse health effects of residents living in places with a higher background level of Hg, due to long-term exposure to chronic levels of Hg through oral intake should not be overlooked. PMID:16914205

  9. Chemical Contaminants as Stratigraphic Markers for the Anthropocene

    NASA Astrophysics Data System (ADS)

    Kruge, M. A.

    2012-12-01

    Thousands and even millions of years from now, widespread anthropogenic contaminants in sediments would likely persist, incorporated into the geological record. They would inadvertently preserve evidence of our present era (informally designated as the Anthropocene Epoch) characterized by large human populations engaged in intensive industrial and agricultural activities. Hypothetical geologists in the distant future would likely find unusually high concentrations of a wide variety of contaminants at stratigraphic levels corresponding to our present time, analogous to the iridium anomaly marking the bolide impact event at the close of the Cretaceous Period. These would include both organic and inorganic substances, such as industrially-derived heavy metals (e.g., Hg, Pb, Cr, Zn) and hydrocarbons, both petrogenic (derived directly from petroleum) and pyrogenic (combustion products). While there are natural sources for these materials, such as volcanic eruptions, wildfires, and oil seeps, their co-occurrence would provide a signature characteristic of human activity. Diagnostic assemblages of organic compounds would carry an anthropogenic imprint. The distribution of polycyclic aromatic hydrocarbons (PAHs) in a sediment sample could distinguish between natural and human sources. Stable isotopic signatures would provide additional evidence. Concentrations of contaminants in the sedimentary record would increase exponentially with increasing proximity to urban source areas, where at present billions of people are collectively consuming vast quantities of fossil fuels and generating large amounts of waste. Aolian and marine transport prior to deposition has been seen at present to globally redistribute detectable amounts of contaminants including Hg and PAHs, even at great distances from principal source areas. For organic contaminants, deposition in an anoxic sedimentary environment could insure their preservation, increasing the likelihood of their inclusion in the long-term stratigraphic record, establishing markers of the Anthropocene Epoch for millions of years to come.

  10. Shuttle on-orbit contamination and environmental effects

    NASA Technical Reports Server (NTRS)

    Leger, L. J.; Jacobs, S.; Ehlers, H. K. F.; Miller, E.

    1985-01-01

    Ensuring the compatibility of the space shuttle system with payloads and payload measurements is discussed. An extensive set of quantitative requirements and goals was developed and implemented by the space shuttle program management. The performance of the Shuttle system as measured by these requirements and goals was assessed partly through the use of the induced environment contamination monitor on Shuttle flights 2, 3, and 4. Contamination levels are low and generally within the requirements and goals established. Additional data from near-term payloads and already planned contamination measurements will complete the environment definition and allow for the development of contamination avoidance procedures as necessary for any payload.

  11. Zebra mussel-directed foodchain transfer of environmental contaminants

    SciTech Connect

    Fisher, S.W.; Bruner, K.A.; Landrum, P.F.

    1994-12-31

    Zebra mussel densities in some near-shore areas of Lake Erie exceed 500,000 individuals m{sup 3}. Because of their large biomass, the zebra mussels can collectively filter the entire volume of Lake Erie`s western basin in approximately 7 days. In so doing, the mussels remove a significant fraction of suspended particles, including algae and sediment. If those particles are contaminated with PCBs, the mussels could potentially redirect contaminant cycling in Lake Erie. Their data show that contaminated particles are a significant source of contaminants for the zebra mussel with sediment being more significant source than algae. When particles are the source of contamination for the zebra mussel, significant foodchain contamination may result from direct consumption of contaminated mussels or via an indirect route in which unassimilated contaminants are shunted into zebra mussel feces and the latter are consumed by benthic invertebrates. Trophic transfer of PCBs from zebra mussel feces to gammarids was measured. Importantly, biomagnification of some PCB congeners occurred during foodchain transfer from particles to mussels to feces such that the indirect route of transfer through ingestion of contaminated feces is more significant ecologically. Implications for Lake Erie foodchains will be discussed.

  12. Development and deployment of a chemical extraction treatment technology for uranium contaminated soil

    SciTech Connect

    Mann, M.J.

    1999-07-01

    The remediation of contaminated soils is a major contributor to the cost of the environmental restoration effort at DOE sites previously employed in the DOE weapons production complex. At the RMI Decommissioning Project (RMIDP) in Ashtabula, Ohio, soil remediation by traditional ship and bury methods comprised over $44 million of the $164 million decommission baseline budget. The RMIDP has developed and is preparing to deploy a chemical treatment technology for washing uranium contaminated soil. Soil washing provides a significant volume reduction alternative to transportation and burial or on-site disposal when all life cycle costs of burial are considered. Soil washing at the RMIDP is projected to save the DOE over $13 million in direct remediation costs of the 40,000 tons of uranium contaminated soil, and $12 million in indirect project savings through schedule reduction. From August 1996 through February 1997, the RMIDP performed Process Definitive Testing (PDT) to validate initial screening study findings regarding the viability of soil washing. PDT defined the operating process parameter requirements for the soil washing carbonate leaching system, and provided valuable design data to be used in production plant design. A 2 ton per batch soil washing plant was designed, constructed, and operated in a 6 month period. Over 68 tons of soil were processed to provide operating data at a scale close to production scale. The data derived from pilot operations proved the technical viability of carbonate leaching on RMI soil and provided sufficient plant operating data to allow a cost-benefit assessment of soil washing to be performed. The RMIDP soil washing production facility design is complete and the facility was started up in April 1999.

  13. DESIGNING ENVIRONMENTAL, ECONOMIC AND ENERGY EFFICIENT CHEMICAL PROCESSES

    EPA Science Inventory

    The design and improvement of chemical processes can be very challenging. The earlier energy conservation, process economics and environmental aspects are incorporated into the process development, the easier and less expensive it is to alter the process design. Process emissio...

  14. SIMULATION MODELS FOR ENVIRONMENTAL MULTIMEDIA ANALYSIS OF TOXIC CHEMICALS

    EPA Science Inventory

    Multimedia understanding of pollutant behavior in the environment is of particular concern for chemicals that are toxic and are subject to accumulation in the environmental media (air, soil, water, vegetation) where biota and human exposure is significant. Multimedia simulation ...

  15. High-Throughput Pharmacokinetics for Environmental Chemicals (SOT)

    EPA Science Inventory

    High throughput screening (HTS) promises to allow prioritization of thousands of environmental chemicals with little or no in vivo information. For bioactivity identified by HTS, toxicokinetic (TK) models are essential to predict exposure thresholds below which no significant bio...

  16. THE TOXCAST PROGRAM FOR PRIORITIZING TOXICITY TESTING OF ENVIRONMENTAL CHEMICALS

    EPA Science Inventory

    The United States Environmental Protection Agency (EPA) is developing methods for utilizing computational chemistry, high-throughput screening (HTS) and various toxicogenomic technologies to predict potential for toxicity and prioritize limited testing resources towards chemicals...

  17. Proteomic analyses of the environmental toxicity of carcinogenic chemicals

    EPA Science Inventory

    Protein expression and posttranslational modifications consistently change in response to the exposure to environmental chemicals. Recent technological advances in proteomics provide new tools for more efficient characterization of protein expression and posttranslational modific...

  18. Microbial and chemical contamination during and after flooding in the Ohio River-Kentucky, 2011.

    PubMed

    Yard, Ellen E; Murphy, Matthew W; Schneeberger, Chandra; Narayanan, Jothikumar; Hoo, Elizabeth; Freiman, Alexander; Lewis, Lauren S; Hill, Vincent R

    2014-09-19

    Surface water contaminants in Kentucky during and after 2011 flooding were characterized. Surface water samples were collected during flood stage (May 2-4, 2011; n = 15) and after (July 25-26, 2011; n = 8) from four different cities along the Ohio River and were analyzed for the presence of microbial indicators, pathogens, metals, and chemical contaminants. Contaminant concentrations during and after flooding were compared using linear and logistic regression. Surface water samples collected during flooding had higher levels of E. coli, enterococci, Salmonella, Campylobacter, E. coli O157:H7, adenovirus, arsenic, copper, iron, lead, and zinc compared to surface water samples collected 3-months post-flood (P < 0.05). These results suggest that flooding increases microbial and chemical loads in surface water. These findings reinforce commonly recommended guidelines to limit exposure to flood water and to appropriately sanitize contaminated surfaces and drinking wells after contamination by flood water. PMID:24967556

  19. Thermal removal of pyrene contamination from soil: basic studies and environmental health implications.

    PubMed Central

    Saito, H H; Bucalá, V; Howard, J B; Peters, W A

    1998-01-01

    Effects of temperature (400-1000 degrees C) and rate of heating to 550 degrees C (100, 1000, 5000 degrees C/sec) on reduction of pyrene contamination in a Superfund-related soil and on yields of volatile products (tars, CO, CO2, methane, acetylene, ethylene) have been measured. Fifty (+/- 3)-milligram thin layers (less than or equal to 150 micron) of 63- to 125-micron soil particles, neat (i.e., without exogenous chemicals), or pretreated with 4.75 wt% of pyrene, were heated for about 1 to 6 sec, under 3 psig (pounds per in.(2) gauge) of helium in a 12-liter sealed chamber. Pyrene removal, defined as the difference in weight loss of neat versus contaminated soil, was virtually immune to heating rate but increased strongly with increasing temperature, approaching 100% at about 530 degrees C. However, for pyrenepolluted soil, excess soil weight loss and modified CO yields were observed above about 500 degrees C for a 1000 degrees C/sec heating rate. These observations suggest that soil chemical reactions with pyrene or pyrene decomposition products augment soil volatilization. Consequently at elevated temperatures, the difference in weight loss protocol may overestimate polycyclic aromatic hydrocarbon (PAH) removal from soil. Increasing heating rate caused yields of CO, CO(2), and acetylene from pyrene-polluted soil to pass through maxima. Heating neat or contaminated soil resulted in at least two gaseous products of particular environmental interest:acetylene, a precursor to PAH in thermal synthesis, and CO, a toxin to human hemoglobin. Images Figure 1 Figure 2 PMID:9703498

  20. Thermal removal of pyrene contamination from soil: basic studies and environmental health implications.

    PubMed

    Saito, H H; Bucal, V; Howard, J B; Peters, W A

    1998-08-01

    Effects of temperature (400-1000 degrees C) and rate of heating to 550 degrees C (100, 1000, 5000 degrees C/sec) on reduction of pyrene contamination in a Superfund-related soil and on yields of volatile products (tars, CO, CO2, methane, acetylene, ethylene) have been measured. Fifty (+/- 3)-milligram thin layers (less than or equal to 150 micron) of 63- to 125-micron soil particles, neat (i.e., without exogenous chemicals), or pretreated with 4.75 wt% of pyrene, were heated for about 1 to 6 sec, under 3 psig (pounds per in.(2) gauge) of helium in a 12-liter sealed chamber. Pyrene removal, defined as the difference in weight loss of neat versus contaminated soil, was virtually immune to heating rate but increased strongly with increasing temperature, approaching 100% at about 530 degrees C. However, for pyrenepolluted soil, excess soil weight loss and modified CO yields were observed above about 500 degrees C for a 1000 degrees C/sec heating rate. These observations suggest that soil chemical reactions with pyrene or pyrene decomposition products augment soil volatilization. Consequently at elevated temperatures, the difference in weight loss protocol may overestimate polycyclic aromatic hydrocarbon (PAH) removal from soil. Increasing heating rate caused yields of CO, CO(2), and acetylene from pyrene-polluted soil to pass through maxima. Heating neat or contaminated soil resulted in at least two gaseous products of particular environmental interest:acetylene, a precursor to PAH in thermal synthesis, and CO, a toxin to human hemoglobin. PMID:9703498

  1. Mussel watch - measurements of chemical pollutants in bivalves as one indicator of coastal environmental quality

    SciTech Connect

    Farrington, J.W.; Davis, A.C.; Tripp, B.W.; Phelps, D.K.; Galloway, W.B.

    1987-01-01

    The utility of the bivalve sentinel organism approach to monitoring for some chemicals of environmental concern in coastal and estuarine areas has been evaluated by regional and national programs and by smaller-scale research efforts during the past 15 years. The extent and severity of coastal contamination by chemicals such as polychlorinated biphenyls, chlorinated pesticides, trace metals, and plutonium was assessed in several bivalve sentinel organism programs. Advantages and limitations of this approach are presented and discussed briefly within the context of both national and international efforts.

  2. Chemical analysis of outgassing contaminants on spacecraft surfaces

    NASA Technical Reports Server (NTRS)

    Mcnutt, R. C.

    1973-01-01

    Methods for analyzing and characterizing outgassing contaminants from such materials as RTV 501 potting compound and S 13 G paint are presented. Fractional distillation of a gross distillate from RTV 501 rubber was carried out and the distilled fractions examined as to their ultraviolet and infrared spectra by gas liquid chromatography. A sensitive technique for structural analysis and molecular identification was found to consist of a gas chromatography-mass spectroscopy system, which was determined to be economically unfeasible at present.

  3. INCIDENCE OF STRESS IN BENTHIC COMMUNITIES ALONG THE U.S. ATLANTIC AND GULF OF MEXICO COASTS WITHIN DIFFERENT RANGES OF SEDIMENT CONTAMINATION FROM CHEMICAL MIXTURES

    EPA Science Inventory

    Synoptic data on concentrations of sediment-associated chemical contaminants and benthic macroinfaunal community structure were collected from 1,389 stations in estuaries along the U.S. Atlantic and Gulf of Mexico coasts as part of the nationwide Environmental Monitoring and Asse...

  4. INCIDENCE OF STRESS IN BENTHIC COMMUNITIES ALONG U.S. ATLANTIC AND GULF OF MEXICO COASTS WITHIN DIFFERENT RANGES OF SEDIMENT CONTAMINATION FROM CHEMICAL MIXTURES

    EPA Science Inventory

    Synoptic data on concentrations of sediment-associated chemical contaminants and benthic macroinfaunal community structure were collected from 1,389 stations in estuaries along the U.S. Atlantic and Gulf of Mexico coasts as part of the nationwide Environmental Monitoring and Asse...

  5. Short-Term and Long-Term Biological Effects of Chronic Chemical Contamination on Natural Populations of a Marine Bivalve

    PubMed Central

    Graber, Marianne; Murillo, Laurence; Becquet, Vanessa; Churlaud, Carine; Fruitier-Arnaudin, Ingrid; Huet, Valérie; Lacroix, Camille; Pante, Eric; Le Floch, Stéphane; Thomas-Guyon, Hélène

    2016-01-01

    Understanding the effects of chronic chemical contamination on natural populations of marine organisms is complex due to the combined effects of different types of pollutants and environmental parameters that can modulate the physiological responses to stress. Here, we present the effects of a chronic contamination in a marine bivalve by combining multiple approaches that provide information on individual and population health. We sampled variegated scallops (Mimachlamys varia) at sites characterized by different contaminants and contamination levels to study the short and long-term (intergenerational) responses of this species to physiological stress. We used biomarkers (SOD, MDA, GST, laccase, citrate synthase and phosphatases) as indicators of oxidative stress, immune system alteration, mitochondrial respiration and general metabolism, and measured population genetic diversity at each site. In parallel, concentration of 14 trace metals and 45 organic contaminants (PAHs, PCBs, pesticides) in tissues were measured. Scallops were collected outside and during their reproductive season to investigate temporal variability in contaminant and biomarker levels. Our analyses revealed that the levels of two biomarkers (Laccase-type phenoloxidase and malondialdehyde) were significantly correlated with Cd concentration. Additionally, we observed significant seasonal differences for four of the five biomarkers, which is likely due to the scallop reproductive status at time of sampling. As a source of concern, a location that was identified as a reference site on the basis of inorganic contaminant levels presented the same level of some persistent organic pollutants (DDT and its metabolites) than more impacted sites. Finally, potential long-term effects of heavy metal contamination were observed for variegated scallops as genetic diversity was depressed in the most polluted sites. PMID:26938082

  6. Short-Term and Long-Term Biological Effects of Chronic Chemical Contamination on Natural Populations of a Marine Bivalve.

    PubMed

    Breitwieser, Marine; Viricel, Amlia; Graber, Marianne; Murillo, Laurence; Becquet, Vanessa; Churlaud, Carine; Fruitier-Arnaudin, Ingrid; Huet, Valrie; Lacroix, Camille; Pante, Eric; Le Floch, Stphane; Thomas-Guyon, Hlne

    2016-01-01

    Understanding the effects of chronic chemical contamination on natural populations of marine organisms is complex due to the combined effects of different types of pollutants and environmental parameters that can modulate the physiological responses to stress. Here, we present the effects of a chronic contamination in a marine bivalve by combining multiple approaches that provide information on individual and population health. We sampled variegated scallops (Mimachlamys varia) at sites characterized by different contaminants and contamination levels to study the short and long-term (intergenerational) responses of this species to physiological stress. We used biomarkers (SOD, MDA, GST, laccase, citrate synthase and phosphatases) as indicators of oxidative stress, immune system alteration, mitochondrial respiration and general metabolism, and measured population genetic diversity at each site. In parallel, concentration of 14 trace metals and 45 organic contaminants (PAHs, PCBs, pesticides) in tissues were measured. Scallops were collected outside and during their reproductive season to investigate temporal variability in contaminant and biomarker levels. Our analyses revealed that the levels of two biomarkers (Laccase-type phenoloxidase and malondialdehyde) were significantly correlated with Cd concentration. Additionally, we observed significant seasonal differences for four of the five biomarkers, which is likely due to the scallop reproductive status at time of sampling. As a source of concern, a location that was identified as a reference site on the basis of inorganic contaminant levels presented the same level of some persistent organic pollutants (DDT and its metabolites) than more impacted sites. Finally, potential long-term effects of heavy metal contamination were observed for variegated scallops as genetic diversity was depressed in the most polluted sites. PMID:26938082

  7. Evaluating legacy contaminants and emerging chemicals in marine environments using adverse outcome pathways and biological effects-directed analysis.

    PubMed

    Hutchinson, Thomas H; Lyons, Brett P; Thain, John E; Law, Robin J

    2013-09-30

    Natural and synthetic chemicals are essential to our daily lives, food supplies, health care, industries and safe sanitation. At the same time protecting marine ecosystems and seafood resources from the adverse effects of chemical contaminants remains an important issue. Since the 1970s, monitoring of persistent, bioaccumulative and toxic (PBT) chemicals using analytical chemistry has provided important spatial and temporal trend data in three important contexts; relating to human health protection from seafood contamination, addressing threats to marine top predators and finally providing essential evidence to better protect the biodiversity of commercial and non-commercial marine species. A number of regional conventions have led to controls on certain PBT chemicals over several years (termed 'legacy contaminants'; e.g. cadmium, lindane, polycyclic aromatic hydrocarbons [PAHs] and polychlorinated biphenyls [PCBs]). Analytical chemistry plays a key role in evaluating to what extent such regulatory steps have been effective in leading to reduced emissions of these legacy contaminants into marine environments. In parallel, the application of biomarkers (e.g. DNA adducts, CYP1A-EROD, vitellogenin) and bioassays integrated with analytical chemistry has strengthened the evidence base to support an ecosystem approach to manage marine pollution problems. In recent years, however,the increased sensitivity of analytical chemistry, toxicity alerts and wider environmental awareness has led to a focus on emerging chemical contaminants (defined as chemicals that have been detected in the environment, but which are currently not included in regulatory monitoring programmes and whose fate and biological impacts are poorly understood). It is also known that natural chemicals (e.g. algal biotoxins) may also pose a threat to marine species and seafood quality. Hence complex mixtures of legacy contaminants, emerging chemicals and natural biotoxins in marine ecosystems represent important scientific, economic and health challenges. In order to meet these challenges and pursue cost-effective scientific approaches that can provide evidence necessary to support policy needs (e.g. the European Marine Strategy Framework Directive), it is widely recognised that there is a need to (i) provide marine exposure assessments for priority contaminants using a range of validated models, passive samplers and biomarkers; (ii) integrate chemical monitoring data with biological effects data across spatial and temporal scales (including quality controls); and (iii) strengthen the evidence base to understand the relationship between exposure to complex chemical mixtures, biological and ecological impacts through integrated approaches and molecular data (e.g. genomics, proteomics and metabolomics). Additionally, we support the widely held view that (iv) that rather than increasing the analytical chemistry monitoring of large number of emerging contaminants, it will be important to target analytical chemistry towards key groups of chemicals of concern using effects-directed analysis. It is also important to evaluate to what extent existing biomarkers and bioassays can address various classes of emerging chemicals using the adverse outcome pathway (AOP) approach now being developed by the Organization for Economic Cooperation and Development (OECD) with respect to human toxicology and ecotoxicology. PMID:23820191

  8. Current methods for evaluating the bioavailability of chemicals from contaminated soils using soil invertebrates

    SciTech Connect

    Lanno, R.P.

    1995-12-31

    Contaminated soils are an extremely complex, variable matrix where many modifying factors of toxicity (e.g., particle size, organic matter content) alter the availability of chemicals to biota. Although many methods have been standardized for assessing the toxicity of contaminated soils to invertebrates and plants, few studies have actually addressed the issue of contaminant bioavailability from soils. Since bioavailability is a measure of uptake of contaminants from the soil by living organisms, one approach to determining bioavailability is to measure residues of contaminants in biota. Body residues related to a specific lethal or sublethal toxicity endpoint offer the unique opportunity to relate bioavailability to biological response. This paper will present an overview of the use of body residues in assessing the bioavailability of soil contaminants by earthworms and soil arthropods. The applications of body residues in the development of soil quality guidelines will also be discussed.

  9. KINETICS OF CHEMICAL & MICROBIAL CONTAMINANTS IN DISTRIBUTION SYSTEMS

    EPA Science Inventory

    Once treated drinking water enters the distribution system, substantial microbial, chemical, and physical changes can occur. Examples of such changes can nclude loss of disinfectant residual, increases in disinfection byproducts (DBP), growth of microbial diversity and population...

  10. DNA damage and repair in haemolymph cells of golden mussel (Limnoperna fortunei) exposed to environmental contaminants.

    PubMed

    Villela, Izabel Vianna; de Oliveira, Iuri Marques; da Silva, Juliana; Henriques, Joo Antonio Pgas

    2006-06-16

    The development of methodologies for biomonitoring freshwater ecosystems is of particular relevance in view of the serious problem of aquatic environmental pollution. The mussel species Limnoperna fortunei (golden mussel) was chosen to be tested as a biomonitor organism based on its population data and distribution. L. fortunei individuals were exposed to UV radiation in vitro, and in vivo to pentachlorophenol (PCP) and copper sulphate (CuSO(4)), with the aim of standardizing comet assay and micronucleus test methodologies and evaluating the potential of this organism as a biomonitor. Haemolymph cells immobilized in agarose on slides exposed to UV radiation showed a dose-response relationship with maximum damage at 4.2 J/m(2). For the chemical tests, individuals were exposed for 2h for the comet assay and 24 and 48 h for the micronucleus test. A dose-response relationship was observed for both chemicals. 3x10(-5) M CuSO(4) induced high genotoxicity, also producing some toxicity after 48 h of exposure. PCP induced maximum damage in both assays at 150 ?g/L. Individuals exposed to PCP showed 100% repair 2 h after the exposure period, as assessed by the comet assay. Exposure to an environmental sample over 7 days confirmed the mussel sensitivity to water contaminants, detected both by the comet assay and the micronucleus test. The results allow us to suggest the golden mussel as a potential biomonitor organism. PMID:16697250

  11. Decision support methods for the environmental assessment of contamination at mining sites.

    PubMed

    Jordan, Gyozo; Abdaal, Ahmed

    2013-09-01

    Polluting mine accidents and widespread environmental contamination associated with historic mining in Europe and elsewhere has triggered the improvement of related environmental legislation and of the environmental assessment and management methods for the mining industry. Mining has some unique features such as natural background pollution associated with natural mineral deposits, industrial activities and contamination located in the three-dimensional sub-surface space, the problem of long-term remediation after mine closure, problem of secondary contaminated areas around mine sites and abandoned mines in historic regions like Europe. These mining-specific problems require special tools to address the complexity of the environmental problems of mining-related contamination. The objective of this paper is to review and evaluate some of the decision support methods that have been developed and applied to mining contamination. In this paper, only those methods that are both efficient decision support tools and provide a 'holistic' approach to the complex problem as well are considered. These tools are (1) landscape ecology, (2) industrial ecology, (3) landscape geochemistry, (4) geo-environmental models, (5) environmental impact assessment, (6) environmental risk assessment, (7) material flow analysis and (8) life cycle assessment. This unique inter-disciplinary study should enable both the researcher and the practitioner to obtain broad view on the state-of-the-art of decision support methods for the environmental assessment of contamination at mine sites. Documented examples and abundant references are also provided. PMID:23456223

  12. Methods for the Determination of Chemical Contaminants in Drinking Water. Training Manual.

    ERIC Educational Resources Information Center

    Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

    This training manual, intended for chemists and technicians with little or no experience in chemical procedures required to monitor drinking water, covers analytical methods for inorganic and organic chemical contaminants listed in the interim primary drinking water regulations. Topics include methods for heavy metals, nitrate, and organic…

  13. A Raman chemical imaging system for detection of contaminants in food

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study presented a preliminary investigation into the use of macro-scale Raman chemical imaging for the screening of dry milk powder for the prescence of chemical contaminants. Melamine was mixed into dry milk at concentrations (w/w) of 0.2%, 0.5%, 1.0%, 2.0%, 5.0%, and 10.0% and images of the ...

  14. RAPID SCREENING OF ENVIRONMENTAL CHEMICALS FOR ESTROGEN RECEPTOR BINDING CAPACITY

    EPA Science Inventory

    Over the last few years, an increased awareness of endocrine disrupting chemicals (EDCs) and their potential to affect wildlife and humans has produced a demand for practical screening methods to identify endocrine activity in a wide range of environmental and industrial chemical...

  15. DEVELOPMENT OF ENVIRONMENTAL INDICES FOR GREEN CHEMICAL PRODUCTION AND USE

    EPA Science Inventory

    Chemical production, use and disposal cause adverse impacts on the environment. Consequently, much research has been conducted to develop methods for estimating the risk of chemicals and to screen them based on environmental impact. Risk assessment may be subdivide...

  16. A Chemical Properties Simulator to Support Integrated Environmental Modeling

    EPA Science Inventory

    Users of Integrated Environmental Modeling (IEM) systems are responsible for defining individual chemicals and their properties, a process that is time-consuming at best and overwhelming at worst, especially for new chemicals with new structures. A software tool is needed to allo...

  17. A Chemical Properties Simulator to Support Integrated Environmental Modeling (proceeding)

    EPA Science Inventory

    Users of Integrated Environmental Modeling (IEM) systems are responsible for defining individual chemicals and their properties, a process that is time-consuming at best and overwhelming at worst, especially for new chemicals with new structures. A software tool is needed to allo...

  18. Characterization and assessment of contaminated soil and groundwater at an organic chemical plant site in Chongqing, Southwest China.

    PubMed

    Liu, Geng; Niu, Junjie; Zhang, Chao; Guo, Guanlin

    2016-04-01

    Contamination from organic chemical plants can cause serious pollution of soil and groundwater ecosystems. To characterize soil contamination and to evaluate the health risk posed by groundwater at a typical organic chemical plant site in Chongqing, China, 91 soil samples and seven groundwater samples were collected. The concentrations of different contaminants and their three-dimensional distribution were determined based on the 3D-krige method. Groundwater chemistry risk index (Chem RI) and cancer risk were calculated based on TRIAD and RBCA models. The chemistry risk indices of groundwater points SW5, SW18, SW22, SW39, SW52, SW80, and SW82 were 0.4209, 0.9972, 0.9324, 0.9990, 0.9991, 1.0000, and 1.0000, respectively, indicating that the groundwater has poor environmental status. By contrast, the reference Yangtse River water sample showed no pollution with a Chem RI of 0.1301. Benzene and 1,2-dichloroethane were the main contaminants in the groundwater and were responsible for the elevated cancer risk. The cumulative health risk of groundwater points (except SW5 and SW18) were all higher than the acceptable baselines of 10(-6), which indicates that the groundwater poses high cancer risk. Action is urgently required to control and remediate the risk for human health and groundwater ecosystems. PMID:26193833

  19. CHEMICAL INDUCTION MIXER VERIFICATION - ENVIRONMENTAL TECHNOLOGY VERIFICATION PROGRAM

    EPA Science Inventory

    The Wet-Weather Flow Technologies Pilot of the Environmental Technology Verification (ETV) Program, which is supported by the U.S. Environmental Protection Agency and facilitated by NSF International, has recently evaluated the performance of chemical induction mixers used for di...

  20. ENVIRONMENTAL IMPLICATIONS OF CHANGES IN THE BROMINATED CHEMICALS INDUSTRY

    EPA Science Inventory

    In light of the large-scale changes occuring within the bromine-based chemicals industry, the U.S. Environmental Protection Agency commissioned a study to investigate the potential for adverse environmental effects that might result from such changes. In particular, EPA was inter...

  1. ENVIRONMENTAL ENGINEERING AND ENDOCRINE DISRUPTING CHEMICALS: JOURNAL ARTICLE

    EPA Science Inventory

    NRMRL-CIN-1600 Sayles*, G.D. Environmental Engineering and Endocrine Disrupting Chemicals. ASCE Journal of Environmental Engineering (Arnold, R.G. (Ed.), Reston, VA: American Society of Civil Engineers) 128 (1):1-2 (2002). EPA/600/J- 02/001. ...

  2. ANIMALS AS SENTINELS OF HUMAN HEALTH HAZARDS OF ENVIRONMENTAL CHEMICALS

    EPA Science Inventory

    A workshop titled "Using Sentinel Species Data to Address the Potential Human Health Effects of Chemicals in the Environmnet," sponsored by the U.S. Army Center for Environmental Health Research, the National Center for Environmental Assessment of the EPA, and the Agency for Toxi...

  3. Mechanism of known environmental teratogens: drugs and chemicals

    SciTech Connect

    Beckman, D.A.; Brent, R.L.

    1986-09-01

    Basic principles of teratology and mechanisms of teratogenesis applicable to human exposures to environmental drugs and chemicals are discussed. The available clinical and experimental animal literature on environmental agents alleged or known to cause human malformations is critically reviewed and summarized. 296 references.

  4. Chemical contaminants in surficial sediment in Coral and Fish Bays, St. John, U.S. Virgin Islands.

    PubMed

    Whitall, David; Pait, Anthony; Hartwell, S Ian

    2015-12-01

    Land based sources of pollution have the potential to negatively impact coral reef ecosystems. Many coral systems, including environmentally sensitive marine protected areas, do not have assessments of their chemical contaminant status (magnitude and extent). Without a status assessment, it is impossible to measure change in a system. This study presents surficial sediment data from Coral and Fish Bays (St. John, US Virgin Islands (USVI)). Portions of these bays are included in Virgin Islands National Park, and Virgin Islands Coral Reef National Monument. A suite of analytes (PCBs, PAHs, pesticides, heavy metals, butyltins) was quantified and compared against other regional data and against previously published sediment quality guidelines (SQG). Contamination from toxic contaminants in the system was generally low when compared to other similar studies and potential toxicity thresholds (SQG). Exceptions to this were copper and total chlordane which exceeded the Effects Range Low (ERL) sediment quality guideline, indicating possible sediment toxicity. This assessment will be useful to coastal managers for tracking environmental change, and ensuring that this marine protected area remains relatively free from toxic contamination. PMID:26427342

  5. Association between indoor environmental contamination by Salmonella enterica and contamination of eggs on layer farms.

    PubMed

    Gole, Vaibhav C; Torok, Valeria; Sexton, Margaret; Caraguel, Charles G B; Chousalkar, Kapil K

    2014-09-01

    This study involves longitudinal and point-in-time surveys of Salmonella carriage and environmental contamination on two commercial cage layer farms positive for Salmonella enterica subsp. enterica serovar Typhimurium (flock A age, 32 weeks; flock B age, 34 weeks). Salmonella-positive fecal, egg belt, and dust samples were all unconditionally associated with eggshells testing positive for Salmonella. The odds of an eggshell testing positive for Salmonella were 91.8, 61.5, and 18.2 times higher when fecal, egg belt, and dust samples, respectively, tested positive for Salmonella. The agreement between the culture-based methods and real-time PCR on preenriched broths for detecting Salmonella was almost perfect for eggshell (observed agreement, 99.19%; kappa coefficient, 0.94) and egg belt samples (observed agreement, 95%; kappa coefficient, 0.88), and it was substantial for fecal (observed agreement, 87.14%; kappa coefficient, 0.47) and floor dust samples (observed agreement, 80.61%; kappa coefficient, 0.58). A 1-log increase in the load of Salmonella detected in the fecal, egg belt, and floor dust samples resulted in 35%, 43%, and 45% increases, respectively (P < 0.001), in the odds of an eggshell testing positive for Salmonella. The multilocus variable-number tandem-repeat analysis (MLVA) patterns of the S. Typhimurium strains isolated from flock A were distinct from those of flock B. S. Typhimurium strains detected from human food poisoning cases exhibited an MLVA pattern similar to those of the strains isolated from flocks A and B. PMID:24966362

  6. Association between Indoor Environmental Contamination by Salmonella enterica and Contamination of Eggs on Layer Farms

    PubMed Central

    Gole, Vaibhav C.; Torok, Valeria; Sexton, Margaret; Caraguel, Charles G. B.

    2014-01-01

    This study involves longitudinal and point-in-time surveys of Salmonella carriage and environmental contamination on two commercial cage layer farms positive for Salmonella enterica subsp. enterica serovar Typhimurium (flock A age, 32 weeks; flock B age, 34 weeks). Salmonella-positive fecal, egg belt, and dust samples were all unconditionally associated with eggshells testing positive for Salmonella. The odds of an eggshell testing positive for Salmonella were 91.8, 61.5, and 18.2 times higher when fecal, egg belt, and dust samples, respectively, tested positive for Salmonella. The agreement between the culture-based methods and real-time PCR on preenriched broths for detecting Salmonella was almost perfect for eggshell (observed agreement, 99.19%; kappa coefficient, 0.94) and egg belt samples (observed agreement, 95%; kappa coefficient, 0.88), and it was substantial for fecal (observed agreement, 87.14%; kappa coefficient, 0.47) and floor dust samples (observed agreement, 80.61%; kappa coefficient, 0.58). A 1-log increase in the load of Salmonella detected in the fecal, egg belt, and floor dust samples resulted in 35%, 43%, and 45% increases, respectively (P < 0.001), in the odds of an eggshell testing positive for Salmonella. The multilocus variable-number tandem-repeat analysis (MLVA) patterns of the S. Typhimurium strains isolated from flock A were distinct from those of flock B. S. Typhimurium strains detected from human food poisoning cases exhibited an MLVA pattern similar to those of the strains isolated from flocks A and B. PMID:24966362

  7. Microarray applications to understand the impact of exposure to environmental contaminants in wild dolphins (Tursiops truncatus).

    PubMed

    Mancia, Annalaura; Abelli, Luigi; Kucklick, John R; Rowles, Teresa K; Wells, Randall S; Balmer, Brian C; Hohn, Aleta A; Baatz, John E; Ryan, James C

    2015-02-01

    It is increasingly common to monitor the marine environment and establish geographic trends of environmental contamination by measuring contaminant levels in animals from higher trophic levels. The health of an ecosystem is largely reflected in the health of its inhabitants. As an apex predator, the common bottlenose dolphin (Tursiops truncatus) can reflect the health of near shore marine ecosystems, and reflect coastal threats that pose risk to human health, such as legacy contaminants or marine toxins, e.g. polychlorinated biphenyls (PCBs) and brevetoxins. Major advances in the understanding of dolphin biology and the unique adaptations of these animals in response to the marine environment are being made as a result of the development of cell-lines for use in in vitro experiments, the production of monoclonal antibodies to recognize dolphin proteins, the development of dolphin DNA microarrays to measure global gene expression and the sequencing of the dolphin genome. These advances may play a central role in understanding the complex and specialized biology of the dolphin with regard to how this species responds to an array of environmental insults. This work presents the creation, characterization and application of a new molecular tool to better understand the complex and unique biology of the common bottlenose dolphin and its response to environmental stress and infection. A dolphin oligo microarray representing 24,418 unigene sequences was developed and used to analyze blood samples collected from 69 dolphins during capture-release health assessments at five geographic locations (Beaufort, NC, Sarasota Bay, FL, Saint Joseph Bay, FL, Sapelo Island, GA and Brunswick, GA). The microarray was validated and tested for its ability to: 1) distinguish male from female dolphins; 2) differentiate dolphins inhabiting different geographic locations (Atlantic coasts vs the Gulf of Mexico); and 3) study in detail dolphins resident in one site, the Georgia coast, known to be heavily contaminated by Aroclor 1268, an uncommon polychlorinated (PCB) mixture. The microarray was able to distinguish dolphins by sex, geographic location, and corroborate previously published health irregularities for the Georgia dolphins. Genes involved in xenobiotic metabolism, development/differentiation and oncogenic pathways were found to be differentially expressed in GA dolphins. The report bridges the advancements in dolphin genome sequencing to the first step towards providing a cost-effective means to screen for indicators of chemical toxin exposure as well as disease status in top level predators. PMID:25479946

  8. Development of Chemical Indicators of Groundwater Contamination Near the Carcass Burial Site

    NASA Astrophysics Data System (ADS)

    Kim, H.; Choi, J.; Kim, M.; Choi, J.; Lee, M.; Lee, H.; Jeon, S.; Bang, S.; Noh, H.; Yoo, J.; Park, S.; Kim, H.; Kim, D.; Lee, Y.; Han, J.

    2011-12-01

    A serious outbreak of foot and mouth disease (FMD) and avian influenza (AI) led to the culling of millions of livestock in South Korea from late 2010 to earlier 2011. Because of the scale of FMD and AI epidemic in Korea and rapid spread of the diseases, mass burial for the disposal of carcass was conducted to halt the outbreak. The improper construction of the burial site or inappropriate management of the carcass burial facility can cause the contamination of groundwater mainly due to the discharges of leachate through the base of disposal pit. The leachate from carcass burial contains by products of carcass decay such as amino acids, nitrate, ammonia and chloride. The presence of these chemical components in groundwater can be used as indicators demonstrating contamination of groundwater with leachate from carcass. The major concern about using these chemical indicators is that other sources including manures, fertilizers and waste waters from human or animal activities already exist in farming area. However, we lack the understanding of how groundwater contamination due to mass burial of carcass can be differentiated from the contamination due to livestock manures which shows similar chemical characteristics. The chemical compositions of the leachate from carcass burial site and the wastewater from livestock manure treatment facilities were compared. The chemical compositions considered include total organic carbon (TOC), total nitrogen (TN), nitrate, organic nitrogen (Organic nitrogen =TN-Ammonium Nitrogen- Nitrate nitrogen), ammonia, chloride, sodium, potassium and amino acids (20 analytes). The ratios of concentrations of the chemical compositions as indicators of contamination were determined to distinguish the sources of contamination in groundwater. Indicators which showed a linear relationship between two factors and revealed a distinct difference between the carcass leachate and livestock manure were chosen. In addition, the background level of the indicators in groundwater which was presumed not to be contaminated with the leachate was also considered. The indicators selected from these step were TN/nitrate nitrogen, organic nitrogen/TN, organic nitrogen/Cl and organic nitrogen/Na. In a similar manner, concentrations and peak pattern of amino acids with LC-MSMS as indicators were also selected. One more step added to identify the source of a contaminant release was the consideration of the transport of 20 amino acids in the subsurface which could significantly change the peak pattern among different amino acids. Six group of amino acid as indicators were chosen and they were Isoleucine/Valine, Leucine/Tryptophane, Valine/Tryptophane, Lysine/Leucine, Lysine/Isoleucine and Methionine/Lysine. The use of chemical indicators was attempted in this study to distinguish the sources of contamination by considering both the concentration of contaminants and the unique patterns of contamination.

  9. Endocrine Profiling and Prioritization of Environmental Chemicals Using ToxCast Data

    PubMed Central

    Reif, David M.; Martin, Matthew T.; Tan, Shirlee W.; Houck, Keith A.; Judson, Richard S.; Richard, Ann M.; Knudsen, Thomas B.; Dix, David J.; Kavlock, Robert J.

    2010-01-01

    Background The prioritization of chemicals for toxicity testing is a primary goal of the U.S. Environmental Protection Agency (EPA) ToxCast program. Phase I of ToxCast used a battery of 467 in vitro, high-throughput screening assays to assess 309 environmental chemicals. One important mode of action leading to toxicity is endocrine disruption, and the U.S. EPAs Endocrine Disruptor Screening Program (EDSP) has been charged with screening pesticide chemicals and environmental contaminants for their potential to affect the endocrine systems of humans and wildlife. Objective The goal of this study was to develop a flexible method to facilitate the rational prioritization of chemicals for further evaluation and demonstrate its application as a candidate decision-support tool for EDSP. Methods Focusing on estrogen, androgen, and thyroid pathways, we defined putative endocrine profiles and derived a relative rank or score for the entire ToxCast library of 309 unique chemicals. Effects on other nuclear receptors and xenobiotic metabolizing enzymes were also considered, as were pertinent chemical descriptors and pathways relevant to endocrine-mediated signaling. Results Combining multiple data sources into an overall, weight-of-evidence Toxicological Priority Index (ToxPi) score for prioritizing further chemical testing resulted in more robust conclusions than any single data source taken alone. Conclusions Incorporating data from in vitro assays, chemical descriptors, and biological pathways in this prioritization schema provided a flexible, comprehensive visualization and ranking of each chemicals potential endocrine activity. Importantly, ToxPi profiles provide a transparent visualization of the relative contribution of all information sources to an overall priority ranking. The method developed here is readily adaptable to diverse chemical prioritization tasks. PMID:20826373

  10. Linking chemical contamination to biological effects in coastal pollution monitoring.

    PubMed

    Beiras, Ricardo; Durán, Iria; Parra, Santiago; Urrutia, Miren B; Besada, Victoria; Bellas, Juan; Viñas, Lucía; Sánchez-Marín, Paula; González-Quijano, Amelia; Franco, María A; Nieto, Óscar; González, Juan J

    2012-01-01

    To establish the connection between pollutant levels and their harmful effects on living resources, coastal monitoring programmes have incorporated biological tools, such as the scope for growth (SFG) in marine mussels and benthic macrofauna community indices. Although the relation between oxygen-depleting anthropogenic inputs and the alteration of benthic communities is well described, the effects of chemical pollutants are unknown because they are not expected to favour any particular taxa. In this study, the combined efforts of five research teams involved in the investigative monitoring of marine pollution allowed the generation of a multiyear data set for Ría de Vigo (NW Iberian Peninsula). Multivariate analysis of these data allowed the identification of the chemical-matrix combinations responsible for most of the variability among sites and the construction of a chemical pollution index (CPI) that significantly (P < 0.01) correlated with biological effects at both the individual and the community levels. We report a consistent reduction in the physiological fitness of local populations of mussels as chemical pollution increases. The energy balance was more sensitive to pollution than individual physiological rates, but the reduction in the SFG was primarily due to significantly decreased clearance rates. We also found a decrease in benthic macrofauna diversity as chemical pollution increases. This diversity reduction resulted not from altered evenness, as the classic paradigm might suggest, but from a loss of species richness. PMID:21805214

  11. Finite element modeling of contaminant transport in soils including the effect of chemical reactions.

    PubMed

    Javadi, A A; Al-Najjar, M M

    2007-05-17

    The movement of chemicals through soils to the groundwater is a major cause of degradation of water resources. In many cases, serious human and stock health implications are associated with this form of pollution. Recent studies have shown that the current models and methods are not able to adequately describe the leaching of nutrients through soils, often underestimating the risk of groundwater contamination by surface-applied chemicals, and overestimating the concentration of resident solutes. Furthermore, the effect of chemical reactions on the fate and transport of contaminants is not included in many of the existing numerical models for contaminant transport. In this paper a numerical model is presented for simulation of the flow of water and air and contaminant transport through unsaturated soils with the main focus being on the effects of chemical reactions. The governing equations of miscible contaminant transport including advection, dispersion-diffusion and adsorption effects together with the effect of chemical reactions are presented. The mathematical framework and the numerical implementation of the model are described in detail. The model is validated by application to a number of test cases from the literature and is then applied to the simulation of a physical model test involving transport of contaminants in a block of soil with particular reference to the effects of chemical reactions. Comparison of the results of the numerical model with the experimental results shows that the model is capable of predicting the effects of chemical reactions with very high accuracy. The importance of consideration of the effects of chemical reactions is highlighted. PMID:17270344

  12. Sequential chemical extraction for a phosphogypsum environmental impact evaluation

    NASA Astrophysics Data System (ADS)

    Gennari, R. F.; Garcia, I.; Medina, N. H.; Silveira, M. A. G.

    2013-05-01

    Phosphogypsum (PG) is gypsum generated during phosphoric acid production. PG is stocked in large stacks or accumulated in lakes; it contains heavy metals and naturally occurring radioactive elements. The metal contamination may affect the functionality, sustainability and biodiversity of ecosystems. In this work, PG samples were analyzed by Plasma Spectrometry. Total metal content and in the extractable fraction of chemical elements were determined. For K, Ni, Zn, Cr, Cd, Ba, Pb and U, the results obtained are lower than those obtained in a Idaho plant are including and also lower than those found in the soil, indicating this PG sample analyzed probably will not cause any additional metal neither natural radiation contamination.

  13. Identification of Chemically Sulfated/desulfated Glycosaminoglycans in Contaminated Heparins and Development of a Simple Assay for the Detection of Most Contaminants in Heparin

    PubMed Central

    Pan, Jing; Qian, Yi; Zhou, Xiaodong; Pazandak, Andrew; Frazier, Sarah B.; Weiser, Peter; Lu, Hong; Zhang, Lijuan

    2010-01-01

    Contaminated heparin was linked to at least 149 deaths and hundreds of adverse reactions. Published report indicates that heparin contaminants were a natural impurity, dermatan sulfate, and a contaminant, oversulfated chondroitin sulfate (OSCS). OSCS was assumed to derive from animal cartilage. By analyzing 26 contaminated heparin lots from different sources, our data indicate that the heparin contaminants were chemically sulfated or chemically sulfated/desulfated glycosaminoglycans (GAGs) consisting of heparan sulfate, chondroitin sulfate, and dermatan sulfate based on monosaccharide quantification, CE, heparin lyase digestion, and liquid chromatography/mass spectrometry analysis. Since currently recommended heparin quality control assays had failed to detect certain heparin contaminants, a simple method that detects most contaminants in heparin was developed. This assay detects specific heparin structures that most contaminants cannot mimic and can be performed in any laboratory equipped with an UV spectrometer. PMID:20657729

  14. Modeling environmental loading rates of municipal wastewater contaminants: steroidal estrogens

    EPA Science Inventory

    Estrogenic compounds in municipal wastewater are of substantial interest because of suspicion that they may cause reproductive disruption in aquatic invertebrates, and because of their potential to contaminate human drinking water sources. Previous work suggests the primary contr...

  15. In vitro toxicity and interactions of environmental contaminants (Arochlor 1254 and mercury) and immunomodulatory agents (lipopolysaccharide and cortisol) on thymocytes from lake trout (Salvelinus namaycush)

    USGS Publications Warehouse

    Miller, Gregory G.; Sweet, Leonard I.; Adams, Jean V.; Omann, Geneva M.; Passino-Reader, Dora R.; Meier, Peter G.

    2002-01-01

    The immunotoxicity of chemical combinations commonly encountered by the lake trout (Salvelinus namaycush) immune system was the focus of this study. It was hypothesised that combinations of an environmental contaminant (mercuric chloride or Aroclor 1254) and an immunomodulatory agent (bacterial endotoxin or cortisol) might interact to produce a greater toxicity than that of the environmental contaminant alone at concentrations typically encountered in piscine blood and other tissues. Thus lake trout thymocytes were isolated and treated with mercuric chloride or Aroclor 1254 in the presence and absence of cortisol or lipopolysaccharide. Incubations were performed for 6 or 20h at 4A?C or 10A?C. Lipopolysaccharide did not affect the toxicity of either contaminant. In contrast, cortisol enhanced the toxicity of both environmental contaminants. Hence, stressors that lead to increased cortisol production, but not lipopolysaccharide directly, may increase the toxicity of mercury and Aroclor 1254 to lake trout thymocytes.

  16. Linking Empirical Estimates of Body Burden of Environmental Chemicals and Wellness using NHANES Data

    PubMed Central

    Gennings, Chris; Ellis, Rhonda; Ritter, Joe

    2011-01-01

    Biomonitoring of industrial chemicals in human tissues and fluids has shown that all people carry a “body burden” of synthetic chemicals. Although measurement of an environmental chemical in a person’s tissues/fluids is an indication of exposure, it does not necessarily mean the exposure concentration is sufficient to cause an adverse effect. Since humans are exposed to multiple chemicals, there may be a combination effect (e.g., additive, synergistic) associated with low-level exposures to multiple classes of contaminants, which may impact a variety of organ systems. The objective of this research is to link measures of body burden of environmental chemicals and a “holistic” measure of wellness. The approach is demonstrated using biomonitoring data from the National Health and Nutrition Examination Surveys (NHANES). Forty-two chemicals were selected for analysis based on their detection levels. Six biological pathway-specific indices were evaluated using groups of chemicals associated with each pathway. Five of the six pathways were negatively associated with wellness. Three non-zero interaction terms were detected which may provide empirical evidence of crosstalk across pathways. The approach identified five of the 42 chemicals from a variety of classes (metals, pesticides, furans, polycyclic aromatic hydrocarbons) as accounting for 71% of the weight linking body burden to wellness. Significant interactions were detected indicating the effect of smoking is exacerbated by body burden of environmental chemicals. Use of a holistic index on both sides of the exposure-health equation is a novel and promising empirical “systems biology” approach to risk evaluation of complex environmental exposures. PMID:22208743

  17. A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach for contaminated sites management.

    PubMed

    Hu, Yan; Wen, Jing-Ya; Li, Xiao-Li; Wang, Da-Zhou; Li, Yu

    2013-10-15

    A dynamic multimedia fuzzy-stochastic integrated environmental risk assessment approach was developed for contaminated sites management. The contaminant concentrations were simulated by a validated interval dynamic multimedia fugacity model, and different guideline values for the same contaminant were represented as a fuzzy environmental guideline. Then, the probability of violating environmental guideline (Pv) can be determined by comparison between the modeled concentrations and the fuzzy environmental guideline, and the constructed relationship between the Pvs and environmental risk levels was used to assess the environmental risk level. The developed approach was applied to assess the integrated environmental risk at a case study site in China, simulated from 1985 to 2020. Four scenarios were analyzed, including "residential land" and "industrial land" environmental guidelines under "strict" and "loose" strictness. It was found that PAH concentrations will increase steadily over time, with soil found to be the dominant sink. Source emission in soil was the leading input and atmospheric sedimentation was the dominant transfer process. The integrated environmental risks primarily resulted from petroleum spills and coke ovens, while the soil environmental risks came from coal combustion. The developed approach offers an effective tool for quantifying variability and uncertainty in the dynamic multimedia integrated environmental risk assessment and the contaminated site management. PMID:23995555

  18. Survey of Chemical Contaminants in the Hanalei River, Kaua'i, Hawai'i, 2001

    USGS Publications Warehouse

    Orazio, Carl E.; May, Thomas W.; Gale, Robert W.; Meadows, John C.; Brumbaugh, William G.; Echols, Kathy R.; Steiner, William W.M.; Berg, Carl J., Jr.

    2007-01-01

    The Hanalei River on the island of Kaua'i in Hawai'i was designated an American Heritage River in 1998, providing special attention to natural resource protection, economic revitalization, and historic and cultural preservation. Agricultural, urban, and tourism-related activities are potential sources of contamination within the Hanalei River watershed. The objective of this study was to measure certain persistent organic chemicals and elements in the Hanalei River. During a relatively low-flow period in December of 2001, samples of native Akupa sleeper fish (Eleotris sandwicensis), freshwater Asian clam (Corbicula fluminea), giant mud crab (Scylla serrata), surface water, and stream bed sediment were collected from a lower estuarine reach of the river near its mouth at Hanalei Bay and from an upper reach at the Hanalei National Wildlife Refuge. Samples were analyzed for residues of urban and agricultural chemicals including organochlorine pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and elements (including mercury, lead, cadmium, arsenic, and selenium). Organic contaminants were extracted from the samples with solvent, enriched, and then analyzed by gas chromatographic analysis with electron capture or mass spectrometric detection. Samples were acid-digested for semi-quantitative analysis for elements by inductively-coupled plasma-mass spectrometry and for quantitative analysis by atomic absorption spectrophotometry. Concentrations of organochlorine pesticides, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls in biota, surface water, and bed sediment sampled from the Hanalei River ranged from nondetectable to very low levels. Polychlorinated biphenyls were below detection in all samples. Dieldrin, the only compound detected in the water samples, was present at very low concentrations of 1-2 nanograms per liter. Akupa sleeper fish and giant mud crabs from the lower reach ranged from 1 to 5 nanograms per gram (wet weight) dieldrin and from less than 0.3 to 2.1 nanograms per gram total chlordane. Concentrations of individual polycyclic aromatic hydrocarbons in the lower reach bed sediments ranged from less than 1 to 190 nanograms per gram (dry weight). Relative concentrations (patterns) of the polycyclic aromatic hydrocarbons in one portion of a sediment sample indicated combustion sources. Concentrations of elements in the surface water, biota, and sediment samples were below toxicity thresholds of ecological concern. In summary, concentrations of the organic contaminants and elements targeted by this study of the Hanalei River in 2001 were below U.S. Environmental Protection Agency probable adverse effects levels for aquatic organisms.

  19. Decline in heavy metal contamination in marine sediments in Jakarta Bay, Indonesia due to increasing environmental regulations

    NASA Astrophysics Data System (ADS)

    Hosono, Takahiro; Su, Chih-Chieh; Delinom, Robert; Umezawa, Yu; Toyota, Tomoyo; Kaneko, Shinji; Taniguchi, Makoto

    2011-04-01

    The 210Pb geochronology, heavy metal concentrations (Zn, Cu, and Pb), and stable Pb isotope ratios ( 206Pb/ 207Pb) of three sediment cores collected from Jakarta Bay were analyzed to decipher the history of heavy metal contamination in the period 1900-2006. The chemical and isotopic analyses clearly suggest that anthropogenic metal accumulation in the sediments began in the 1920s and increased greatly from the 1970s until the end of the 1990s. From the end of the 1990s to 2006, accumulation rates were constant or decreased for Zn and Pb near the coastal industrialized area. Comparison of economic data and sociological information suggests that the decline in the concentrations of heavy metals could be attributed to the stricter environmental regulations which were enforced at the end of 1990s. However, metal contamination is currently still an important cause of concern in dealing with environmental preservation and protection in Jakarta Bay.

  20. Environmental contaminants in hospital settings and progress in disinfecting techniques.

    PubMed

    Messina, Gabriele; Ceriale, Emma; Lenzi, Daniele; Burgassi, Sandra; Azzolini, Elena; Manzi, Pietro

    2013-01-01

    Medical devices, such as stethoscopes, and other objects found in hospital, such as computer keyboards and telephone handsets, may be reservoirs of bacteria for healthcare-associated infections. In this cross-over study involving an Italian teaching hospital we evaluated microbial contamination (total bacterial count (TBC) at 36°C/22°C, Staphylococcus spp., moulds, Enterococcus spp., Pseudomonas spp., E. coli, total coliform bacteria, Acinetobacter spp., and Clostridium difficile) of these devices before and after cleaning and differences in contamination between hospital units and between stethoscopes and keyboards plus handsets. We analysed 37 telephone handsets, 27 computer keyboards, and 35 stethoscopes, comparing their contamination in four hospital units. Wilcoxon signed-rank and Mann-Whitney tests were used. Before cleaning, many samples were positive for Staphylococcus spp. and coliforms. After cleaning, CFUs decreased to zero in most comparisons. The first aid unit had the highest and intensive care the lowest contamination (P < 0.01). Keyboards and handsets had higher TBC at 22°C (P = 0.046) and mould contamination (P = 0.002) than stethoscopes. Healthcare professionals should disinfect stethoscopes and other possible sources of bacterial healthcare-associated infections. The cleaning technique used was effective in reducing bacterial contamination. Units with high patient turnover, such as first aid, should practise stricter hygiene. PMID:24286078

  1. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    SciTech Connect

    Not Available

    1992-03-01

    This report contains information related to the sampling and chemical analysis of ground water at the Wright-Patterson Air Force Base. It is part of a field investigation of ground water contamination.

  2. FASTER SCIENCE FOR BETTER DECISIONS: CHARACTERIZING ENVIRONMENTAL CONTAMINANT RISK FROM HIGH THROUGHPUT DATA

    EPA Science Inventory

    Tens of thousands of chemicals and other man-made contaminants exist in our environment, but only a fraction of these have been characterized for their potential risk to humans and there is widespread interest in closing this data gap in order to better manage contaminant risk. C...

  3. Toxicological benchmarks for screening contaminants of potential concern for effects on sediment-associated biota: 1994 Revision. Environmental Restoration Program

    SciTech Connect

    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.

  4. CHEMICALLY-ENHANCED DISSOLUTION AND MOBILIZATION OF RESIDUAL CONTAMINANTS

    EPA Science Inventory

    Pore-scale micromodels and a computer-controlled imaging system will be used to examine fluid dynamics and phase behavior during chemically-enhanced NAPL dissolution and mobilization. Mechanistic insights gained at this microscopic level will be used to help explain observations...

  5. TRANSPORT OF CHEMICAL CONTAMINANTS IN KARST TERRANES: OUTLINE AND SUMMARY

    EPA Science Inventory

    Chemical spills that reach an aquifer in karst terranes do not behave like those in granular or highly fractured aquifers. pills reaching diffuse-flow aquifers display relatively slow transport, are radially dispersive, and can be tracked through the use of monitoring wells. pill...

  6. Food safety. [chemical contaminants and human toxic diseases

    NASA Technical Reports Server (NTRS)

    Pier, S. M.; Valentine, J. L.

    1975-01-01

    Illness induced by unsafe food is a problem of great public health significance. This study relates exclusively to the occurrence of chemical agents which will result in food unsafe for human consumption since the matter of food safety is of paramount importance in the mission and operation of the manned spacecraft program of the National Aeronautics and Space Administration.

  7. Emerging Disinfection By-Products and Other Emerging Environmental Contaminants: Whats New

    EPA Science Inventory

    This presentation will cover new research and concerns regarding drinking water disinfection by-products (DBPs) and other emerging environmental contaminants, such as perfluorooctanoic acid (PFOA), pharmaceuticals, perchlorate, benzotriazoles, fuel additives (e.g., ethylene dibro...

  8. ENVIRONMENTAL CONTAMINATION FROM TRACE ELEMENTS IN COAL PREPARATION WASTES. A LITERATURE REVIEW AND ASSESSMENT

    EPA Science Inventory

    The report gives results of collecting and evaluating available information on the chemistry and behavior of trace elements in coal preparation wastes, and assessing the potential for environmental contamination from the trace elements in these wastes. Only limited attention has ...

  9. Emerging Disinfection By-Products and Other Emerging Environmental Contaminants: What’s New

    EPA Science Inventory

    This presentation will cover new research and concerns regarding drinking water disinfection by-products (DBPs) and other emerging environmental contaminants, such as perfluorooctanoic acid (PFOA), pharmaceuticals, perchlorate, benzotriazoles, fuel additives (e.g., ethylene dibro...

  10. USE OF ULTRASOUND IN MONITORING CHEMICAL CONTAMINATION IN WATER

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) has been examining the potential for combining sonication with other technologies for monitoring specific classes of organic pollutants in water. ollutants are decomposed into ions which can be detected using known electrochemical te...

  11. Synergistic activation of estrogen receptor with combinations of environmental chemicals

    SciTech Connect

    Arnold, S.F.; Klotz, D.M.; Collins, B.M.

    1996-06-07

    Certain chemicals in the environment are estrogenic. The low potencies of the compounds, when studied singly, suggest that they may have little effect on biological systems. The estrogenic potencies of combinations of such chemicals were screened in a simple yeast estrogen potencies of combination of such chemicals were screened in a simple yeast estrogen systems (YES) containing human estrogen receptor (hER). Combinations of two weak environmental estrogens, such as dieldrin, endosulfan, or toxaphene, were 100 times as potent in hER-mediated transactivation as any chemical alone. Hydroxylated polychlorinated biphenyls shown previously to synergistically alter sexual development in turtles also synergized in the YES. The synergistic interaction of chemical mixtures with the estrogen receptor may have profound environmental implications. These results may represent a previously uncharacterized level of regulation of estrogen-associated responses. 32 refs., 3 figs., 3 tabs.

  12. ENVIRONMENTAL MASS SPECTROMETRY: EMERGING CONTAMINANTS AND CURRENT ISSUES

    EPA Science Inventory

    This review covers developments in environmental mass spectrometry over the period of 2000-2001. A few significant references that appeared between January and February 2002 are also included. The previous Environmental Mass Spectrometry review was very comprehensive, including...

  13. MEETING IN GERMANY: EMERGING ENVIRONMENTAL CONTAMINANTS AND CURRENT ISSUES

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise (including potential adverse health effects, bioaccumulation, and widespread distribution). This presentation will discuss emerging environmental c...

  14. MEETING IN CHINA: EMERGING ENVIRONMENTAL CONTAMINANTS AND CURRENT ISSUES

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise (including potential adverse health effects, bioaccumulation, and widespread distribution). This presentation will discuss emerging environmental c...

  15. MEETING IN NEW ZEALAND: EMERGING ENVIRONMENTAL CONTAMINANTS AND CURRENT ISSUES

    EPA Science Inventory

    Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise (including potential adverse health effects, bioaccumulation, and widespread distribution). This presentation will discuss emerging environmental c...

  16. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    SciTech Connect

    Not Available

    1991-10-01

    In April 1990 Wright-Patterson Air Force Base (WPAFB) initiated an investigation to evaluate a potential CERCLA removal action to prevent, to the extent practicable, the migration of ground-water contamination in the Mad River Valley Aquifer within and across WPAFB boundaries. The action will be based on a Focused Feasibility Study with an Action Memorandum serving as a decision document that is subject to approval by the Ohio Environmental Protection Agency. The first phase (Phase 1) of this effort involves an investigation of ground-water contamination migrating across the southwest boundary of Area C and across Springfield Pike adjacent to Area B. Task 4 of Phase 1 is a field investigation to collect sufficient additional information to evaluate removal alternatives. The field investigation will provide information in the following specific areas of study: water-level data which will be used to permit calibration of the ground-water flow model to a unique time in history; and ground-water quality data which will be used to characterize the current chemical conditions of ground water.

  17. Physical and Chemical Environmental Abstraction Model

    SciTech Connect

    E. Nowak

    2000-11-09

    As directed by a written development plan (CRWMS M&O 1999a), Task 1, an overall conceptualization of the physical and chemical environment (P/CE) in the emplacement drift is documented in this Analysis/Model Report (AMR). Included are the physical components of the engineered barrier system (EBS). The intended use of this descriptive conceptualization is to assist the Performance Assessment Department (PAD) in modeling the physical and chemical environment within a repository drift. It is also intended to assist PAD in providing a more integrated and complete in-drift geochemical model abstraction and to answer the key technical issues raised in the U.S. Nuclear Regulatory Commission (NRC) Issue Resolution Status Report (IRSR) for the Evolution of the Near-Field Environment (NFE) Revision 2 (NRC 1999). EBS-related features, events, and processes (FEPs) have been assembled and discussed in ''EBS FEPs/Degradation Modes Abstraction'' (CRWMS M&O 2000a). Reference AMRs listed in Section 6 address FEPs that have not been screened out. This conceptualization does not directly address those FEPs. Additional tasks described in the written development plan are recommended for future work in Section 7.3. To achieve the stated purpose, the scope of this document includes: (1) the role of in-drift physical and chemical environments in the Total System Performance Assessment (TSPA) (Section 6.1); (2) the configuration of engineered components (features) and critical locations in drifts (Sections 6.2.1 and 6.3, portions taken from EBS Radionuclide Transport Abstraction (CRWMS M&O 2000b)); (3) overview and critical locations of processes that can affect P/CE (Section 6.3); (4) couplings and relationships among features and processes in the drifts (Section 6.4); and (5) identities and uses of parameters transmitted to TSPA by some of the reference AMRs (Section 6.5). This AMR originally considered a design with backfill, and is now being updated (REV 00 ICN1) to address the design without backfill. This design change is described in ''Monitored Geologic Repository Project Description Document'' (CRWMS M&O 2000c). The design change will result in a greater ability of the waste packages to reject heat after closure of the repository, thereby maintaining the two thermal requirements. The first requirement is for protection of the fuel cladding, and the second requires that a section of the rock pillar between drifts remain below the boiling temperature of water, providing a path for water drainage.

  18. Unit environmental transport assessment of contaminants from Hanford`s past-practice waste sites. Hanford Remedial Action Environmental Impact Statement

    SciTech Connect

    Whelan, G.; Buck, J.W.; Castleton, K.J.

    1995-06-01

    The US Department of Energy, Richland Operations Office (DOE-RL) contracted Pacific Northwest Laboratory (PNL) to provide support to Advanced Sciences, Incorporated (ASI) in implementing tile regional no-action risk assessment in the Hanford Remedial Action Environmental Impact Statement. Researchers at PNL were charged with developing unit concentrations for soil, groundwater, surface water, and air at multiple locations within an 80-km radius from the center of tile Hanford installation. Using the Multimedia Environmental Pollutant Assessment System (MEPAS), PNL simulated (1) a unit release of one ci for each radionuclide and one kg for each chemical from contaminated soils and ponded sites, (2) transport of the contaminants in and through various environmental media and (3) exposure/risk of four exposure scenarios, outlined by the Hanford Site Baseline Remedial Action Methodology. These four scenarios include residential, recreational, industrial, and agricultural exposures. Spacially and temporally distributed environmental concentrations based on unit releases of radionuclides and chemicals were supported to ASI in support of the HRA-EIS. Risk for the four exposure scenarios, based on unit environment concentrations in air, water, and soil. were also supplied to ASI. This report outlines the procedure that was used to implement the unit transport portion of the HRA-EIS baseline risk assessment. Deliverables include unit groundwater, surface water, air, and soil concentrations at multiple locations within an 80-km radius from the center of the Hanford installation.

  19. UPTAKE AND DEPURATION OF ORGANIC CONTAMINANTS BY BLUE MUSSELS (MYTILUS EDULIS) EXPOSED TO ENVIRONMENTALLY CONTAMINATED SEDIMENT

    EPA Science Inventory

    Experiments were designed to expose blue mussels (Mytilus edulis) to contaminated sediment collected from Narragansett Bay, Rhode Island, USA in 1982. Measurements were taken to allow comparisons of the uptake and depuration of polycyclic aromatic hydrocarbons (PAHs) and polychlo...

  20. Environmental and safety obligations of the Chemical Weapons Convention

    SciTech Connect

    Tanzman, E.A.

    1994-04-07

    Among its many unique and precedent-setting provisions, the Chemical Weapons Convention (CWC) includes important requirements for States Parties to protect the public safety and the environment in the course of carrying out the treaty. These obligations will apply to the destruction of chemical weapons, of former chemical weapons production facilities, and to other activities under the Convention such as the verification scheme. This morning, I will briefly discuss the Convention`s safety and environmental obligations, concentrating on their effects in this country as the United States chemical weapons stockpile is destroyed.

  1. Environmental neurotoxicity of chemicals and radiation

    SciTech Connect

    Verity, M.A. )

    1993-06-01

    Epidemiologic and societal concerns continue to stimulate studies in the field of environmental neurotoxicology. Although the role of heavy metals, aluminum, and iron are unclear in the etiology of human neurodegenerative disorders, these toxins have provided fertile ground for in vivo and in vitro experimental studies to elucidate their role in neurotoxic injury. Experimental models of clinical syndromes are discussed with special relevance to developmental neurotoxicology. Cycloleucine, tellurium, and 1,3-dinitrobenzene provide models of subacute combined degeneration, primary peripheral nerve demyelination, and thiamine deficiency-like lesions, respectively. Increasing attention is being given to irradiation neurotoxicity, especially in the developing or young central nervous system. A fuller understanding of the pathogenesis of low-dose irradiation injury allows for a clearer understanding of its neurobiology and also provides a more rational approach to understanding an interventional therapy associated with brain irradiation for childhood neoplasia. 43 refs.

  2. The problem of living in a world contaminated with chemicals

    SciTech Connect

    Metcalf, R.L.

    1990-12-31

    The proliferation of xenobiotic chemicals in the global environment poses living problems for each of us aboard {open_quotes}spaceship earth.{close_quotes} Seven case studies are presented that illustrate the magnitude of the problem that can result from waiting to identify toxic hazards until there have been decades of {open_quotes}human guinea pig{close_quotes} exposure. 25 refs., 5 tabs.

  3. Environmental contaminants in bald eagles in the Columbia River estuary

    SciTech Connect

    Anthony, R.G.; Garrett, M.G. ); Schuler, C.A. )

    1993-01-01

    Eggs, blood, and carcasses of bald eagles (Haliaeetus leucocephalus) and fish were collected and breeding success of eagles was monitored in the Columbia River estuary, 1980-87, to determine if contaminants were having an effect on productivity. High levels of dichloro diphenyl dichloroethylene (DDE), polychlorinated biphenyls (PCB's), and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were found in eggs, blood from adults, and 2 eagle carcasses. Detectable levels of DDE and PCB's were found in blood of nestlings indicating they were exposed to these contaminants early in life. Increasing concentrations of DDE and PCB's with age also indicated accumulation of these contaminants. Adult eagles also had higher levels of mercury (Hg) in blood than subadults or young indicating accumulation with age. The high levels of DDE and PCB's were associated with eggshell thinning ([bar x] = 10%) and with productivity ([bar x] = 0.56 young/occupied site) that was lower than that of healthy populations (i.e., [ge]1.00 young/occupied site). DDE and PCB's had a deleterious effect on reproduction of bald eagles in the estuary. The role dioxins play in eagle reproduction remains unclear, but concentrations in eagle eggs were similar to those in laboratory studies on other species where dioxins adversely affected hatchability of eggs. Probable source of these contaminants include dredged river sediments and hydroelectric dams, and the proper management of each may reduce the amount of contaminants released into the Columbia River estuary. 46 refs., 1 fig., 4 tabs.

  4. Environmentally-Induced Malignancies: An In Vivo Model to Evaluate the Health Impact of Chemicals in Mixed Waste

    SciTech Connect

    Maria Pallavicini

    2001-05-04

    Occupational and environmental exposure to organic ligands, solvents, fuel hydrocarbons, and polychlorinated biphenyls are linked with increased risk of hematologic malignancies. DOE facilities and waste sites in the U.S. are contaminated with mixtures of potentially hazardous chemicals such as metals, organic ligands, solvents, fuel hydrocarbons, polychlorinated biphenyls and radioactive isotopes. A major goal of this project was to establish linkage between chemical/radiation exposure and induction of genomic damage in target populations with the capability to undergo transformation.

  5. Recent advances in chemical imaging technology for the detection of contaminants for food safety and security

    NASA Astrophysics Data System (ADS)

    Priore, Ryan J.; Olkhovyk, Oksana; Drauch, Amy; Treado, Patrick; Kim, Moon; Chao, Kaunglin

    2009-05-01

    The need for routine, non-destructive chemical screening of agricultural products is increasing due to the health hazards to animals and humans associated with intentional and unintentional contamination of foods. Melamine, an industrial additive used to increase flame retardation in the resin industry, has recently been used to increase the apparent protein content of animal feed, of infant formula, as well as powdered and liquid milk in the dairy industry. Such contaminants, even at regulated levels, pose serious health risks. Chemical imaging technology provides the ability to evaluate large volumes of agricultural products before reaching the consumer. In this presentation, recent advances in chemical imaging technology that exploit Raman, fluorescence and near-infrared (NIR) are presented for the detection of contaminants in agricultural products.

  6. Environmental contaminants in bald eagle eggs from the Aleutian archipelago.

    PubMed

    Anthony, Robert G; Miles, A Keith; Ricca, Mark A; Estes, James A

    2007-09-01

    We collected 136 fresh and unhatched eggs from bald eagle (Haliaeetus leucocephalus) nests and assessed productivity on eight islands in the Aleutian archipelago, 2000 to 2002. Egg contents were analyzed for a broad spectrum of organochlorine (OC) contaminants, mercury (Hg), and stable isotopes of carbon (delta13C) and nitrogen (delta15N). Concentrations of polychlorinated biphenyls (SigmaPCBs), p,p'-dichlorodiphenyldichloroethylene (DDE), and Hg in bald eagle eggs were elevated throughout the archipelago, but the patterns of distribution differed among the various contaminants. Total PCBs were highest in areas of past military activities on Adak and Amchitka Islands, indicating local point sources of these compounds. Concentrations of DDE and Hg were higher on Amchitka Island, which was subjected to much military activity during World War II and the middle of the 20th century. Concentrations of SigmaPCBs also were elevated on islands with little history of military activity (e.g., Amlia, Tanaga, Buldir), suggesting non-point sources of PCBs in addition to point sources. Concentrations of DDE and Hg were highest in eagle eggs from the most western Aleutian Islands (e.g., Buldir, Kiska) and decreased eastward along the Aleutian chain. This east-to-west increase suggested a Eurasian source of contamination, possibly through global transport and atmospheric distillation and/or from migratory seabirds. Eggshell thickness and productivity of bald eagles were normal and indicative of healthy populations because concentrations of most contaminants were below threshold levels for effects on reproduction. Contrary to our predictions, contaminant concentrations were not correlated with stable isotopes of carbon (delta13C) or nitrogen (delta15N) in eggs. These latter findings indicate that contaminant concentrations were influenced more by point sources and geographic location than trophic status of eagles among the different islands. PMID:17702538

  7. Environmental contaminants in bald eagle eggs from the Aleutian archipelago

    USGS Publications Warehouse

    Anthony, R.G.; Miles, A.K.; Ricca, M.A.; Estes, J.A.

    2007-01-01

    We collected 136 fresh and unhatched eggs from bald eagle (Haliaeetus leucocephalus) nests and assessed productivity on eight islands in the Aleutian archipelago, 2000 to 2002. Egg contents were analyzed for a broad spectrum of organochlorine (OC) contaminants, mercury (Hg), and stable isotopes of carbon (??13C) and nitrogen (??15N). Concentrations of polychlorinated biphenyls (??PCBs), p,p???- dichlorodiphenyldichloroethylene (DDE), and Hg in bald eagle eggs were elevated throughout the archipelago, but the patterns of distribution differed among the various contaminants. Total PCBs were highest in areas of past military activities on Adak and Amchitka Islands, indicating local point sources of these compounds. Concentrations of DDE and Hg were higher on Amchitka Island, which was subjected to much military activity during World War II and the middle of the 20th century. Concentrations of ??PCBs also were elevated on islands with little history of military activity (e.g., Amlia, Tanaga, Buldir), suggesting non-point sources of PCBs in addition to point sources. Concentrations of DDE and Hg were highest in eagle eggs from the most western Aleutian Islands (e.g., Buldir, Kiska) and decreased eastward along the Aleutian chain. This east-to-west increase suggested a Eurasian source of contamination, possibly through global transport and atmospheric distillation and/or from migratory seabirds. Eggshell thickness and productivity of bald eagles were normal and indicative of healthy populations because concentrations of most contaminants were below threshold levels for effects on reproduction. Contrary to our predictions, contaminant concentrations were not correlated with stable isotopes of carbon (??13C) or nitrogen (??15N) in eggs. These latter findings indicate that contaminant concentrations were influenced more by point sources and geographic location than trophic status of eagles among the different islands. ?? 2007 SETAC.

  8. Drilling Fluid Contamination during Riser Drilling Quantified by Chemical and Molecular Tracers

    NASA Astrophysics Data System (ADS)

    Inagaki, F.; Lever, M. A.; Morono, Y.; Hoshino, T.

    2012-12-01

    Stringent contamination controls are essential to any type of microbiological investigation, and are particularly challenging in ocean drilling, where samples are retrieved from hundreds of meters below the seafloor. In summer 2012, Integrated Ocean Drilling Expedition 337 aboard the Japanese vessel Chikyu pioneered the use of chemical tracers in riser drilling while exploring the microbial ecosystem of coalbeds 2 km below the seafloor off Shimokita, Japan. Contamination tests involving a perfluorocarbon tracer that had been successfully used during past riserless drilling expeditions were complemented by DNA-based contamination tests. In the latter, likely microbial contaminants were targeted via quantitative polymerase chain reaction assays using newly designed, group-specific primers. Target groups included potential indicators of (a) drilling mud viscosifiers (Xanthomonas, Halomonas), (b) anthropogenic wastewater (Bifidobacterium, Blautia, Methanobrevibacter), and (c) surface seawater (SAR 11, Marine Group I Archaea). These target groups were selected based on past evidence suggesting viscosifiers, wastewater, and seawater as the main sources of microbial contamination in cores retrieved by ocean drilling. Analyses of chemical and molecular tracers are in good agreement, and indicate microorganisms associated with mud viscosifiers as the main contaminants during riser drilling. These same molecular analyses are then extended to subseafloor samples obtained during riserless drilling operations. General strategies to further reduce the risk of microbial contamination during riser and riserless drilling operations are discussed.

  9. Effects of varying environmental parameters on trace contaminant concentrations in the NASA Space Station Reference Configuration

    NASA Technical Reports Server (NTRS)

    Brewer, Dana A.; Hall, John B., Jr.

    1986-01-01

    An evaluation is made of the NASA Space Station Reference Configuration trace contaminant production and depletion level effects of CO2, O2, humidity, temperature, and pressure variations, on the basis of a computer model of the Reference Configuration's chemical reactions and physical processes as functions of time. The effects of changes in the initial concentrations of such contaminants as nonmethane hydrocarbons and nitrogen oxides are also examined, and these are found to result in more significant changes in the concentration levels of trace contaminants than pressure and humidity variations. O2 and CO2 changes are found to have negligible effects on trace contaminant concentrations.

  10. Environmental Analysis of Endocrine Disrupting Effects from Hydrocarbon Contaminants in the Ecosystem

    SciTech Connect

    McLachlan, John A.

    2000-06-01

    This annual report summarizes the progress of three years of a three-year grant awarded to the Center for Bioenvironmental Research (CBR) at Tulane and Xavier Universities. The objective of this project is to determine how environmental contaminants, namely hydrocarbons, can act as hormones or anti-hormones in different species present in aquatic ecosystems. The three major areas of research include (1) a biotechnology based screening system to identify potential hormone mimics and antagonists; (2) an animal screening system to identify biomarkers of endocrine effects; and (3) a literature review to identify compounds at various DOE sites that are potential endocrine disruptors. Species of particular focus in this study are those which can serve as sentinel species (e.g., amphibians) and, thus, provide early warning signals for more widespread impacts on an ecosystem and its wildlife and human inhabitants. The focus of the literature research was to provide an analysis of the contaminants located on or around various Department of Energy (DOE) sites that are or have the potential to function as endocrine disruptors and to correlate the need for studying endocrine disruptors to DOE's programmatic needs. Previous research within the Center for Bioenvironmental Research at Tulane and Xavier Universities has focused on understanding the effects of environmental agents on the human and wildlife health and disease. In particular this research has focused on how exogenous agents can function to mimic or disrupt normal endocrine signaling, i.e. estrogen, thyroid within various systems from whole animal studies with fish, amphibians and insects to human cancer cell lines. Significant work has focused on the estrogenic and anti-estrogenic action of both synthetic organochlorine chemicals and naturally produced phytochemicals. Recent projects have extended these research objectives to examination of these environmental agents on the symbiotic relationship between nitrogen fixing rhizobial bacteria and leguminous plants. This research will form the foundation for future experiments into the genetic manipulation of plants to potentially promote greater or more specific symbiotic relationships between plant and Rhizobium allowing this biological phenomenon to be used in a greater number of crop types. Future technology developments could include the genetic engineering of crops suitable for in situ vadose zone 2 bioremediation (via microbes) and phytoremediation (through the crop, itself) in contaminated DOE sites.

  11. U.S. Environmental Protection Agency and Emerging Contaminants

    EPA Science Inventory

    In the past decade, the scientific community and general public have become increasingly aware of the potential for the presence of unregulated, and generally unmonitored contaminants, found at low concentrations (sub-ug/L) in surface, ground and drinking water. The most common...

  12. PPCPS AS ENVIRONMENTAL CONTAMINANTS: AN OVERVIEW OF THE SCIENCE

    EPA Science Inventory

    Pharmaceuticals and personal care products (PPCPs) comprise a large, diverse array of contaminants that

    can enter the environment from the combined activities, actions, and behaviors of multitudes of individuals

    as well as from veterinary and agricultural use (http:...

  13. Chemical Genomics Profiling of Environmental Chemical Modulation of Human Nuclear Receptors

    EPA Science Inventory

    The large and increasing number of chemicals released into the environment demand more efficient and cost effective approaches for assessing environmental chemical toxicity. The U.S. Tox21 program has responded to this challenge by proposing alternative strategies for toxicity te...

  14. Dutch plan sets environmental targets for chemical industry

    SciTech Connect

    Layman, P.L. )

    1993-11-01

    The Dutch effort is a covenant--established between the nation's government and its chemical industry--to move the Netherlands forward in sustainable development, toward the year 2010, by cutting emissions from chemical production at both large and small chemical companies. The agreement is even accepted, in principle, by many of the country's tough environmental groups, although they have serious reservations on such aspects as timing and extent of the efforts. The chemical industry has committed itself to supporting the national plant, which sets forth firm sectoral goals for 2000 and targets for 2010. The government, in turn, has pledged to not unilaterally change its standards or requirements during this time. The Dutch government thereby achieves its strategic goals of lessened environmental pollution. And the industry's managers can incorporate the goals into their long-term investment planning.

  15. DNA-polyfluorophore Chemosensors for Environmental Remediation: Vapor-phase Identification of Petroleum Products in Contaminated Soil

    PubMed Central

    Jiang, Wei; Wang, Shenliang; Yuen, Lik Hang; Kwon, Hyukin; Ono, Toshikazu

    2013-01-01

    Contamination of soil and groundwater by petroleum-based products is an extremely widespread and important environmental problem. Here we have tested a simple optical approach for detecting and identifying such industrial contaminants in soil samples, using a set of fluorescent DNA-based chemosensors in pattern-based sensing. We used a set of diverse industrial volatile chemicals to screen and identify a set of five short oligomeric DNA fluorophores on PEG-polystyrene microbeads that could differentiate the entire set after exposure to their vapors in air. We then tested this set of five fluorescent chemosensor compounds for their ability to respond with fluorescence changes when exposed to headgas over soil samples contaminated with one of ten different samples of crude oil, petroleum distillates, fuels, lubricants and additives. Statistical analysis of the quantitative fluorescence change data (as ?(R,G,B) emission intensities) revealed that these five chemosensors on beads could differentiate all ten product mixtures at 1000 ppm in soil within 30 minutes. Tests of sensitivity with three of the contaminant mixtures showed that they could be detected and differentiated in amounts at least as low as one part per million in soil. The results establish that DNA-polyfluorophores may have practical utility in monitoring the extent and identity of environmental spills and leaks, while they occur and during their remediation. PMID:23878719

  16. Chemical coagulation-based processes for trace organic contaminant removal: current state and future potential.

    PubMed

    Alexander, Jonathan T; Hai, Faisal I; Al-Aboud, Turki M

    2012-11-30

    Trace organic contaminants have become an increasing cause of concern for governments and water authorities as they attempt to respond to the potential challenges posed by climate change by implementing sustainable water cycle management practices. The augmentation of potable water supplies through indirect potable water reuse is one such method currently being employed. Given the uncertainty surrounding the potential human health impacts of prolonged ingestion of trace organic contaminants, it is vital that effective and sustainable treatment methods are utilized. The purpose of this article is to provide a comprehensive literature review of the performance of the chemical coagulation process in removing trace organic contaminants from water. This study evaluated the removal data collated from recent research relating to various trace organic contaminants during the coagulation process. It was observed that there is limited research data relating to the removal of trace organic contaminants using coagulation. The findings of this study suggest that there is a gap in the current research investigating the potential of new types of coagulants and exploring coagulation-based hybrid processes to remove trace organic contaminants from water. The data analysed in this study regarding removal efficiency suggests that, even for the significantly hydrophobic compounds, hydrophobicity is not the sole factor governing removal of trace organic contaminants by coagulation. This has important implications in that the usual practice of screening coagulants based on turbidity (suspended solid) removal proves inadequate in the case of trace organic contaminant removal. PMID:22922457

  17. Chemicals and environmentally caused diseases in developing countries

    SciTech Connect

    Jamall, I.S.; Davis, B. )

    1991-06-01

    This chapter discusses international aspects of diseases resulting from exposure to chemical pollutants in the environment, with an emphasis on developing countries. These countries share many of the same problems of air, water, and pesticide pollution that face the more industrialized countries. In developing countries, however, the problems are compounded by a number of unique situations, viz., economic priorities, high burden of infectious diseases, impoverishment, and absence of a regulatory framework for the disposal of toxic chemicals. This discussion emphasizes the importance of interactions among toxicants, malnutrition, and infectious diseases for both urban and rural populations insofar as these interactions contribute to disease. Toxicants not only produce disease directly but also exacerbate diseases with other causes. Specific examples from developing countries demonstrate how human health effects from exposures to environmental chemicals can be assessed. While they do not strictly fall under the rubric of developing countries, the public health consequences of inadequate control of environmental pollution in the East European countries should demonstrate the magnitude of the problem, except that in developing countries the public health consequence of environmental chemicals will be aggravated by the widespread malnutrition and high prevalence of infectious diseases. Much needs to be done before we can adequately quantify the contribution of environmental chemicals to morbidity and mortality in developing countries with the level of sophistication now evident in the charting of infectious diseases in these countries. 52 references.

  18. Certified reference materials for inorganic and organic contaminants in environmental matrices.

    PubMed

    Ulberth, Franz

    2006-10-01

    Chemical measurements often constitute the basis for informed decision-making at different levels in society; sound decision-making is possible only if the quality of the data used is uncompromised. To guarantee the reliability and comparability of analytical data an intricate system of quality-assurance measures has to be put into effect in a laboratory. Reference materials and, in particular, certified reference materials (CRMs) are essential for achieving traceability and comparability of measurement results between laboratories and over time. As in any other domain of analytical chemistry, techniques used to monitor the levels and fate of contaminants in the environment must be calibrated using appropriate calibration materials, and the methods must be properly validated using fit-for-purpose matrix-matched CRMs, to ensure confidence in the data produced. A sufficiently large number of matrix CRMs are available for analysis of most elements, and the group of chemicals known as persistent organic pollutants, in environmental compartments and biota. The wide variety of analyte/level/matrix/matrix property combinations available from several suppliers enables analysts to select CRMs which sufficiently match the properties of the samples they analyse routinely. Materials value-assigned for the so-called emerging pollutants are scarce at the moment, though an objective of current development programmes of CRM suppliers is to overcome this problem. PMID:16953324

  19. PHARMACEUTICALS AS ENVIRONMENTAL CONTAMINANTS: AN OVERVIEW OF THE SCIENCE

    EPA Science Inventory

    This important outcome results from the way risk is perceived, which in turn is little affected by factual weight-of-evidence. Essentially, drugs in drinking water supplies are considered "out-of-place" chemicals and as such are sometimes looked upon as "chemical weeds" by the co...

  20. Biomarker strategies to evaluate the environmental effects of chemicals.

    PubMed Central

    Walker, C H

    1998-01-01

    Environmental risk assessment of chemicals depends on the production of toxicity data for surrogate species of mammals, birds, and fish and on making comparisons between these and estimated or predicted environmental concentrations of the chemicals. This paper gives an overview of biomarker assays and strategies that might be used as alternatives, that is, to replace, reduce, or refine currently used ecotoxicity tests that cause suffering to vertebrates. In the present context a biomarker is a biologic response to an environmental chemical at the individual level or below which demonstrates a departure from normal status. Of immediate interest and relevance are nondestructive assays that provide a measure of toxic effect in vertebrate species and that can be used in both laboratory and parallel field studies. A major shortcoming of this approach is that such assays are currently only available for a limited number of chemicals, primarily when the mode of action is known. Nondestructive assays can be performed on blood, skin, excreta, and eggs of birds, fish, reptiles, and amphibians. An interesting recent development is the use of vertebrate cell cultures, including transgenic cell lines that have been developed specifically for toxicity testing. The ultimate concern in ecotoxicology is the effects of chemicals at the level of populations and above. Current risk assessment practices do not address this problem. The development of biomarker strategies could be part of a movement toward more ecologic end points in the safety evaluation of chemicals, which would effect a reduction in animal tests that cause suffering. PMID:9599708

  1. Geochemistry Of Lead In Contaminated Soils: Effects Of Soil Physico-Chemical Properties

    NASA Astrophysics Data System (ADS)

    Saminathan, S.; Sarkar, D.; Datta, R.; Andra, S. P.

    2006-05-01

    Lead (Pb) is an environmental contaminant with proven human health effects. When assessing human health risks associated with Pb, one of the most common exposure pathways typically evaluated is soil ingestion by children. However, bioaccessibility of Pb primarily depends on the solubility and hence, the geochemical form of Pb, which in turn is a function of site specific soil chemistry. Certain fractions of ingested soil-Pb may not dissociate during digestion in the gastro-intestinal tract, and hence, may not be available for transport across the intestinal membrane. Therefore, this study is being currently performed to assess the geochemical forms and bioaccessibility of Pb in soils with varying physico-chemical properties. In order to elucidate the level of Pb that can be ingested and assimilated by humans, an in-vitro model that simulates the physiological conditions of the human digestive system has been developed and is being used in this study. Four different types of soils from the Immokalee (an acid sandy soil with minimal Pb retention potential), Millhopper (a sandy loam with high Fe/Al content), Pahokee (a muck soil with more than 80% soil organic matter), and Tobosa series (an alkaline soil with high clay content) were artificially contaminated with Pb as lead nitrate at the rate equivalent to 0, 400, 800, and 1200 mg/kg dry soil. Analysis of soils by a sequential extraction method at time zero (immediately after spiking) showed that Immokalee and Millhopper soils had the highest amount of Pb in exchangeable form, whereas Pahokee and Tobosa soils had higher percentages of carbonate-bound and Fe/Al-bound Pb. The results of in-vitro experiment at time zero showed that majority of Pb was dissolved in the acidic stomach environment in Immokalee, Millhopper, and Tobosa, whereas it was in the intestinal phase in Pahokee soils. Because the soil system is not in equilibrium at time zero, the effect of soil properties on Pb geochemistry is not clear as yet. The subsequent analysis of soils (after 6 and 8 months months) is expected to better demonstrate the influence of soil properties on human bioaccessibility of Pb in contaminated soils. Furthermore, the geochemical forms of Pb will be correlated with bioaccessible Pb to identify those soil-Pb species with higher solubility in the human gastrointestinal system. Key words: Lead, Geochemical species, Bioaccessibility, In-vitro model, Health risk

  2. High throughput heuristics for prioritizing human exposure to environmental chemicals.

    PubMed

    Wambaugh, John F; Wang, Anran; Dionisio, Kathie L; Frame, Alicia; Egeghy, Peter; Judson, Richard; Setzer, R Woodrow

    2014-11-01

    The risk posed to human health by any of the thousands of untested anthropogenic chemicals in our environment is a function of both the hazard presented by the chemical and the extent of exposure. However, many chemicals lack estimates of exposure intake, limiting the understanding of health risks. We aim to develop a rapid heuristic method to determine potential human exposure to chemicals for application to the thousands of chemicals with little or no exposure data. We used Bayesian methodology to infer ranges of exposure consistent with biomarkers identified in urine samples from the U.S. population by the National Health and Nutrition Examination Survey (NHANES). We performed linear regression on inferred exposure for demographic subsets of NHANES demarked by age, gender, and weight using chemical descriptors and use information from multiple databases and structure-based calculators. Five descriptors are capable of explaining roughly 50% of the variability in geometric means across 106 NHANES chemicals for all the demographic groups, including children aged 6-11. We use these descriptors to estimate human exposure to 7968 chemicals, the majority of which have no other quantitative exposure prediction. For thousands of chemicals with no other information, this approach allows forecasting of average exposure intake of environmental chemicals. PMID:25343693

  3. GUIDANCE ON SELECTING AGE GROUPS FOR MONITORING AND ASSESSING CHILDHOOD EXPOSURES TO ENVIRONMENTAL CONTAMINANTS

    EPA Science Inventory

    This guidance document provides a set of early-lifestage age groups for Environmental Protection Agency scientists to consider when assessing childrens exposure to environmental contaminants and the resultant potential dose. These recommended age groups are based on current und...

  4. GUIDANCE ON SELECTING AGE GROUPS FOR MONITORING AND ASSESSING CHILDHOOD EXPOSURES TO ENVIRONMENTAL CONTAMINANTS

    EPA Science Inventory

    This guidance document provides a set of early-lifestage age groups for Environmental Protection Agency scientists to consider when assessing children’s exposure to environmental contaminants and the resultant potential dose. These recommended age groups are based on current und...

  5. The prediction of toxic mode of action for environmental pollutants based on physico-chemical properties

    SciTech Connect

    Boxall, A.B.A.; Watts, C.D.; Bresnen, G.M.; Dearden, J.C.; Scoffin, R.

    1995-12-31

    Aquatic ecosystems receive a wide range of potentially toxic contaminants. One approach to measure the environmental impact of these compounds is to perform costly and detailed experimental investigations. A quick and cost-effective alternative is to predict the likely effects of chemical contaminants using quantitative structure activity relationships (QSARs) which relate effects to chemical structure. One problem with the predictive approach is that QSARs can be established and used only for compounds with a common mode of toxic action. It is therefore important that a compound is assigned to the correct mode of action and that the correct QSAR is used. Two kinds of approach can be used to address this problem. In the first a compound is assigned to a class based on responses observed during experimental tests. The other approach uses chemical structural information e.g. the OECD method where compounds are classed as inert, less inert, reactive or specific acting based on chemical structure. The objective of this study was to determine whether compounds could be classified into one of the four OECD classes solely on the basis of their physico-chemical properties. Approximately 800 compounds were assigned to an OECD class and a range of properties were calculated. Discriminant analysis demonstrated that a large proportion of these compounds could be classified correctly based on two properties, namely a molecular connectivity index ({sup 2}{sub x}) and an electronic parameter (E{sub HOMO}).

  6. Reducing drinking water supply chemical contamination: risks from underground storage tanks.

    PubMed

    Enander, Richard T; Hanumara, R Choudary; Kobayashi, Hisanori; Gagnon, Ronald N; Park, Eugene; Vallot, Christopher; Genovesi, Richard

    2012-12-01

    Drinking water supplies are at risk of contamination from a variety of physical, chemical, and biological sources. Ranked among these threats are hazardous material releases from leaking or improperly managed underground storage tanks located at municipal, commercial, and industrial facilities. To reduce human health and environmental risks associated with the subsurface storage of hazardous materials, government agencies have taken a variety of legislative and regulatory actions--which date back more than 25 years and include the establishment of rigorous equipment/technology/operational requirements and facility-by-facility inspection and enforcement programs. Given a history of more than 470,000 underground storage tank releases nationwide, the U.S. Environmental Protection Agency continues to report that 7,300 new leaks were found in federal fiscal year 2008, while nearly 103,000 old leaks remain to be cleaned up. In this article, we report on an alternate evidence-based intervention approach for reducing potential releases from the storage of petroleum products (gasoline, diesel, kerosene, heating/fuel oil, and waste oil) in underground tanks at commercial facilities located in Rhode Island. The objective of this study was to evaluate whether a new regulatory model can be used as a cost-effective alternative to traditional facility-by-facility inspection and enforcement programs for underground storage tanks. We conclude that the alternative model, using an emphasis on technical assistance tools, can produce measurable improvements in compliance performance, is a cost-effective adjunct to traditional facility-by-facility inspection and enforcement programs, and has the potential to allow regulatory agencies to decrease their frequency of inspections among low risk facilities without sacrificing compliance performance or increasing public health risks. PMID:22642774

  7. Chemodynamics: transport and behavior of chemicals in the environment--a problem in environmental health.

    PubMed Central

    Freed, V H; Chiou, C T; Haque, R

    1977-01-01

    In the manufacture and use of the several thousand chemicals employed by technological societies, portions of these chemicals escape or are intentionally introduced into the environment. The behavior, fate, and to some extent the effects produced by these chemicals are a result of a complex interaction of the properties of the chemical with the various processes governing transport, degradation, sequestration, and uptake by organisms. In addition, such processes as adsorption, evaporation, partitioning, and degradation are influenced by ambient conditions of temperature, air movement, moisture, presence of other chemicals, and the concentration and properties of the subject chemicals. These influence the level and extent of exposure to these chemicals that man might receive. Study of the physiochemical properties and extent of exposure to these chem;cals that man might receive. Study of the physiochemical properties of compounds in relation to these various processes has provided a basis for better understanding of the quantitative behavior. Such information is useful in development of predictive models on behavior and fate of the chemicals in relation to human exposure. Beyond this, it provides information that could be used to devise procedures of manufacture, use, and disposal that would minimize environmental contamination. Some of the physical principles involved in chemodynamics are presented in this review. PMID:598352

  8. The lead content of plants and animals as indicators of environmental contamination

    SciTech Connect

    Adaudi, A.O.; Gbodi, T.A.; Aliu, Y.O. )

    1990-10-01

    Lead content of tissues from some edible plants, pigeons and a vulture, and from human and cattle blood were determined to gain insight into the extent of environmental lead contamination in Zaria and Kaduna environs of Kaduna state of Nigeria. The results suggest that environmental lead contamination in these areas was insignificant when compared to values from developed countries like US. However, there is need for more work of this nature on a regional basis to ascertain the true picture of total environmental lead pollution in Nigeria.

  9. Importance of stationarity for geostatistical assessment of environmental contamination

    SciTech Connect

    Dagdelen, K.; Turner, A.K.

    1996-12-31

    This paper describes a geostatistical case study to assess TCE contamination from multiple point sources that is migrating through the geologically complex conditions with several aquifers. The paper highlights the importance of the stationarity assumption by demonstrating how biased assessments of TCE contamination result when ordinary kriging of the data that violates stationarity assumptions. Division of the data set into more homogeneous geologic and hydrologic zones improved the accuracy of the estimates. Indicator kriging offers an alternate method for providing a stochastic model that is more appropriate for the data. Further improvement in the estimates results when indicator kriging is applied to individual subregional data sets that are based on geological considerations. This further enhances the data homogeneity and makes use of stationary model more appropriate. By combining geological and geostatistical evaluations, more realistic maps may be produced that reflect the hydrogeological environment and provide a sound basis for future investigations and remediation.

  10. Incorporating biologically based models into assessments of risk from chemical contaminants

    NASA Technical Reports Server (NTRS)

    Bull, R. J.; Conolly, R. B.; De Marini, D. M.; MacPhail, R. C.; Ohanian, E. V.; Swenberg, J. A.

    1993-01-01

    The general approach to assessment of risk from chemical contaminants in drinking water involves three steps: hazard identification, exposure assessment, and dose-response assessment. Traditionally, the risks to humans associated with different levels of a chemical have been derived from the toxic responses observed in animals. It is becoming increasingly clear, however, that further information is needed if risks to humans are to be assessed accurately. Biologically based models help clarify the dose-response relationship and reduce uncertainty.

  11. Hazard Assessment of Chemical Air Contaminants Measured in Residences

    SciTech Connect

    Logue, J.M.; McKone, T.E.; Sherman, M. H.; Singer, B.C.

    2010-05-10

    Identifying air pollutants that pose a potential hazard indoors can facilitate exposure mitigation. In this study, we compiled summary results from 77 published studies reporting measurements of chemical pollutants in residences in the United States and in countries with similar lifestyles. These data were used to calculate representative mid-range and upper bound concentrations relevant to chronic exposures for 267 pollutants and representative peak concentrations relevant to acute exposures for 5 activity-associated pollutants. Representative concentrations are compared to available chronic and acute health standards for 97 pollutants. Fifteen pollutants appear to exceed chronic health standards in a large fraction of homes. Nine other pollutants are identified as potential chronic health hazards in a substantial minority of homes and an additional nine are identified as potential hazards in a very small percentage of homes. Nine pollutants are identified as priority hazards based on the robustness of measured concentration data and the fraction of residences that appear to be impacted: acetaldehyde; acrolein; benzene; 1,3-butadiene; 1,4-dichlorobenzene; formaldehyde; naphthalene; nitrogen dioxide; and PM{sub 2.5}. Activity-based emissions are shown to pose potential acute health hazards for PM{sub 2.5}, formaldehyde, CO, chloroform, and NO{sub 2}.

  12. Active capping technology: a new environmental remediation of contaminated sediment.

    PubMed

    Zhang, Chang; Zhu, Meng-Ying; Zeng, Guang-Ming; Yu, Zhi-Gang; Cui, Fang; Yang, Zhong-Zhu; Shen, Liu-Qing

    2016-03-01

    The management and treatment of contaminated sediment is a worldwide problem and poses major technical and economic challenges. Nowadays, various attempts have been committed to investigating a cost-effective way in contaminated sediment restoration. Among the remediation options, in situ capping turns out to be a less expensive, less disruptive, and more durable approach. However, by using the low adsorption capacity materials, traditional caps do not always fulfill the reduction of risks that can be destructive for human health, ecosystem, and even natural resources. Active caps, therefore, are designed to employ active materials (activated carbon, apatite, zeolite, organoclay, etc.) to strengthen their adsorption and degradation capacity. The active capping technology promises to be a permanent and cost-efficient solution to contaminated sediments. This paper provides a review on the types of active materials and the ways of these active materials employed in recent active capping studies. Cap design considerations including site-specific conditions, diffusion/advection, erosive forces, and active material selection that should be noticed in an eligible remediation project are also presented. PMID:26762937

  13. Biomonitoring of Environmental Status and Trends (BEST) Program: Field Procedures for Assessing the Exposure of Fish to Environmental Contaminants

    USGS Publications Warehouse

    Schmitt, Christopher J.; Blazer, Vicki; Dethloff, Gail M.; Tillitt, Donald E.; Gross, Timothy S.; Bryant, Wade L.; DeWeese, L. Rod; Smith, Stephen B.; Goede, Ronald W.; Bartish, Timothy M.; Kubiak, Timothy J.

    1999-01-01

    This document describes procedures used to collect information, tissues, and fluids for documenting the exposure of fish to environmental contaminants. For the procedures described here, fish are captured (preferably by electrofishing) and held alive until processing (generally <1 h). Fish are weighed, measured, and examined for grossly visible external lesions and pathologies. A blood sample is collected by caudal veinipuncture using a needle and syringe. The fish is subdued and it's abdominal cavity opened. The internal organs are dissected from the fish for examination. The sex of the fish is determined by direct observation of its gonads. The liver is weighed (most species) and cut into small cubes and flash-frozen in cryogenic vials, which are stored and shipped in dry ice or liquid nitrogen. Additional liver cubes plus all grossly visible anomalies are preserved for histopathology. The gonads and spleen are weighed, and samples are preserved for histopathology. The kidneys are examined, and histopathology samples collected. A gill sample is also collected and preserved. All remaining tissues are returned to the carcass, which is wrapped in foil, labeled for chemical analysis, and chilled. Individual fish carcasses are composited by station, species, and gender; frozen; and shipped to the analytical laboratory. Procedures are also described for record keeping; processing blood to obtain serum and plasma; flash-freezing samples; cleaning equipment; and preventing the transport of living organisms among waterways. A list of necessary equipment and supplies is also provided.

  14. Environmental sentinel biomonitors: integrated response systems for monitoring toxic chemicals

    NASA Astrophysics Data System (ADS)

    van der Schalie, William H.; Reuter, Roy; Shedd, Tommy R.; Knechtges, Paul L.

    2002-02-01

    Operational environments for military forces are becoming potentially more dangerous due to the increased number, use, and misuse of toxic chemicals across the entire range of military missions. Defense personnel may be exposed to harmful chemicals as a result of industrial accidents or intentional or unintentional action of enemy, friendly forces, or indigenous populations. While there has been a significant military effort to enable forces to operate safely and survive and sustain operations in nuclear, biological, chemical warfare agent environments, until recently there has not been a concomitant effort associated with potential adverse health effects from exposures of deployed personnel to toxic industrial chemicals. To provide continuous real-time toxicity assessments across a broad spectrum of individual chemicals or chemical mixtures, an Environmental Sentinel Biomonitor (ESB) system concept is proposed. An ESB system will integrate data from one or more platforms of biologically-based systems and chemical detectors placed in the environment to sense developing toxic conditions and transmit time-relevant data for use in risk assessment, mitigation, and/or management. Issues, challenges, and next steps for the ESB system concept are described, based in part on discussions at a September 2001 workshop sponsored by the U.S. Army Center for Environmental Health Research.

  15. Glutathione-S-transferase activity of Fucus spp. as a biomarker of environmental contamination.

    PubMed

    Cairro, E; Couderchet, M; Soares, A M V M; Guilhermino, L

    2004-12-20

    Coastal zones are important areas from both ecological and economical points of view. However, in the last decades, in several regions of the globe, they have been increasingly impacted by complex discharges of contaminants and by marine traffic accidents. The Portuguese Atlantic coast is particularly exposed to these contaminants due to the proximity of important navigation routes. Several rocky shore organisms have been tested and used as bioindicators of environmental contamination. However, to the best of our knowledge Fucus spp., which are key species in rocky shore communities, have not been used as bioindicators in monitoring studies based on biomarkers. The objective of this study was to investigate the potential of glutathione-S-transferase (GST) activity of several Fucus species (Fucus ceranoides, Fucus spiralis var. platycarpus, Fucus spiralis var. spiralis and Fucus vesiculosus var. vesiculosus) to discriminate sites with different contamination levels along the Portuguese Northwestern coast, between the Minho river estuary and the Aveiro's Lagoon, as an environmental biomarker. With the exception of F. spiralis var. spiralis, for which a confusing pattern of activity was found requiring further analysis, all the other species and varieties showed higher GST levels in more contaminated sites than in less contaminated ones, indicating that Fucus spp. are suitable for use as bioindicators and their GSTs as biomarkers of environmental contamination in coastal zones and estuaries. PMID:15588640

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

    SciTech Connect

    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.

  17. Developmental Thyroid Hormone Disruption: Prevalence, Environmental Contaminants and Neurodevelopmental Consequences

    EPA Science Inventory

    Thyroid hormones (TH) are critical for growth and development and particularly brain development. There are numerous environmental agents that lead to marginal reductions of circulating TH. Although it is clear that severe developmental hypothyroidism is profoundly detrimental to...

  18. Meeting in Dallas: Emerging Environmental Contaminants: What's New

    EPA Science Inventory

    Scientific meeting presentation. Much has been achieved in the way of environmental protection over the last 30 years. However, as we learn more, new concerns arise (including potential adverse health effects, bioaccumulation, and widespread distribution). This presentation will...

  19. Prenatal exposure to environmental contaminants and behavioural problems at age 7-8years.

    PubMed

    Sioen, Isabelle; Den Hond, Elly; Nelen, Vera; Van de Mieroop, Els; Croes, Kim; Van Larebeke, Nik; Nawrot, Tim S; Schoeters, Greet

    2013-09-01

    Animal studies showed that the developing brain is particularly sensitive to chemical exposure. Human studies carried out in areas with high exposures have proven neurodevelopmental disorders in relation to e.g. lead and PCBs. Whether these chemicals are associated with behavioural problems in childhood at current environmental levels is not well known. Therefore, we assessed the association between prenatal exposure to lead, cadmium, PCBs, dioxin-like compounds, HCB and p,p'-DDE and behavioural problems in 7-8year old children. Prenatal exposure data were obtained from the Flemish mother-new-born cohort. Lead, cadmium, PCBs, dioxin-like compounds, HCB and p,p'-DDE were analysed in cord blood. When the child reached 7-8years, 270 mothers completed the Strengths and Difficulties Questionnaire assessing their children's behavioural health. We found that doubling the prenatal lead exposure (cord blood lead levels) was associated with a 3.43 times higher risk for hyperactivity in both boys and girls. In addition, total difficulties were 5.08 times more likely in the highest tertile for prenatal lead exposure compared to the lowest tertile. In girls, total difficulties were 4.92 more likely when doubling cord blood p,p'-DDE, whereas no significant association was found in boys. Further, we noted in boys a 1.53 times higher risk for emotional problems when doubling cord blood cadmium, whereas no significant association was found in girls. These results indicate that the presence of environmental contaminants influences the mental health of the next generation. PMID:23845936

  20. XPS chemical analysis of tholins: the oxygen contamination

    NASA Astrophysics Data System (ADS)

    Carrasco, N.; Jomard, F.; Vigneron, J.; Cernogora, G.

    2013-12-01

    In Titan's atmosphere, solid organic aerosols are initiated in the upper atmosphere by the photo-dissociation and photo-ionization of N2 and CH4. In order to simulate this complex chemistry several experimental setups have been built, among them plasma experiments. The aerosol analogues produced in such plasma discharges contain oxygen, as a few percents of the elemental composition, despite the absence of oxygen source in the reactive medium [1]. The present study aims at studying the origin of such systematic oxygen incorporation in tholins. A low pressure (0.9mbar) RF CCP discharge is used described in [2]. Gas mixtures of N2 and CH4 (from 1 to 10% of CH4) are injected continuously. The plasma discharge leads to the production of analogues of Titan's atmospheric aerosols: both as grains in the volume [1] and as thin films on the surface of the reactor [3]. SiO2 substrates of 1cm diameter and 1mm thickness are placed on the grounded electrode of the discharge. Organic films are deposited during 2 hours in order to have films thickness less than 1μm. After the two hours, samples are recovered at ambient air for ex-situ analysis. Two complementary analyses are performed to analyse the thin film chemical composition: XPS and SIMS, in order to probe both the surface and depth profile. References [1] Sciamma-O'brien E., Carrasco N., Szopa C., Buch A., Cernogora G. Icarus 209, 2 (2010) 704-714 [2] Alcouffe G., Cavarroc M., Cernogora G., Ouni F., Jolly A., Boufendi L., Szopa C. Plasma Sources Science and Technology 19, 1 (2010) 015008 (11pp) [3] Mahjoub A., Carrasco N., Dahoo P.-R., Gautier T., Szopa C., Cernogora G. Icarus 221, 2 (2012) 670-677.

  1. Environmental management: Integrating ecological evaluation, remediation, restoration, natural resource damage assessment and long-term stewardship on contaminated lands

    PubMed Central

    Burger, Joanna

    2014-01-01

    Ecological evaluation is essential for remediation, restoration, and Natural Resource Damage Assessment (NRDA), and forms the basis for many management practices. These include determining status and trends of biological, physical, or chemical/radiological conditions, conducting environmental impact assessments, performing remedial actions should remediation fail, managing ecosystems and wildlife, and assessing the efficacy of remediation, restoration, and long-term stewardship. The objective of this paper is to explore the meanings of these assessments, examine the relationships among them, and suggest methods of integration that will move environmental management forward. While remediation, restoration, and NRDA, among others, are often conducted separately, it is important to integrate them for contaminated land where the risks to ecoreceptors (including humans) can be high, and the potential damage to functioning ecosystems great. Ecological evaluations can range from inventories of local plants and animals, determinations of reproductive success of particular species, levels of contaminants in organisms, kinds and levels of effects, and environmental impact assessments, to very formal ecological risk assessments for a chemical or other stressor. Such evaluations can range from the individual species to populations, communities, ecosystems or the landscape scale. Ecological evaluations serve as the basis for making decisions about the levels and kinds of remediation, the levels and kinds of restoration possible, and the degree and kinds of natural resource injuries that have occurred because of contamination. Many different disciplines are involved in ecological evaluation, including biologists, conservationists, foresters, restoration ecologists, ecological engineers, economists, hydrologist, and geologists. Since ecological evaluation forms the basis for so many different types of environmental management, it seems reasonable to integrate management options to achieve economies of time, energy, and costs. Integration and iteration among these disciplines is possible only with continued interactions among practitioners, regulators, policy-makers, Native American Tribes, and the general public. PMID:18687455

  2. Environmental laws regulating chemicals: Uses of information in decision making under environmental statutes

    SciTech Connect

    Gaba, J.M.

    1990-12-31

    Three areas are addressed in this paper: generic issues that arise simply in the process of decision-making under environmental statutes; different decision-making standards under various environmental statutes; and efforts to legislate a {open_quotes}safe{close_quotes} or {open_quotes}acceptable{close_quotes} risk from exposure to carcinogenic chemicals.

  3. Prediction of chemical contaminants and food compositions by near infrared spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prediction of Food Adulteration by Infrared Spectroscopy H. Zhuang Quality and Safety Assessment Research Unit, ARS-USDA, 950 College Station Road, Athens, GA 30605 Food adulteration, including both chemical contamination and composition alternation, has been one of major quality and/or safety c...

  4. Methods for the Determination of Chemical Contaminants in Drinking Water. Instructors Handbook.

    ERIC Educational Resources Information Center

    Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

    This instructor's manual presents information for a training course in analytical methods for inorganic and organic chemical contaminants listed in the interim primary drinking water regulations. Topics focus on: (1) pre-course activities, including course logistics, equipment, and facilities; (2) sample agendas; (3) lesson plans for specific…

  5. REMEDIATION OF SOILS CONTAMINATED WITH WOOD-TREATMENT CHEMICALS (PCP AND CREOSOTE)

    EPA Science Inventory

    PCP and creosote PAHs are found in most of the contaminated soils at wood-treatment sites. The treatment methods currently being used for such soils include soil washing, incineration, and biotreatment. Soil washing involves removal of the hazardous chemicals from soils ...

  6. Recent advances in chemical imaging technology for the detection of contaminants for food safety and security

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The need for routine, non-destructive chemical screening of agricultural products is increasing due to the health hazards to animals and humans associated with intentional and unintentional contamination of foods. Melamine, an industrial additive used to increase flame retardation in the resin indus...

  7. Chemical Spill in West Virginia Triggers More Studies to Understand Contaminants

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2014-02-01

    Although a major chemical spill that contaminated the water supply for nearly 300,000 people living near the Elk River in and around Charleston, W.Va., took place more than a month ago, experts at a 10 February congressional hearing still were not willing to definitively state that the water is safe to use again.

  8. TOXICITY AND MUTAGENICITY OF A MIXTURE OF 25 CHEMICALS FOUND IN CONTAMINATED GROUNDWATER

    EPA Science Inventory

    A defined mixture of 25 chemicals that are often found in contaminated ground water was prepared as a water solution and studied for mutagenicity in bacteria, for prophage induction in bacteria, for palatability and effect on weight-gain in rats and mice, and for cytogenetic effe...

  9. Influences of solution chemical conditions on mobilization of TNT from contaminated soil

    SciTech Connect

    Dante, D.A.; Tiller, C.L.; Pennell, K.D.

    1996-12-31

    2,4,6-trinitrotoluene (TNT) and its byproducts are common contaminants on US military installations. Many potential remediation processes are in part limited by the transfer of TNT from the contaminated soil into the aqueous phase. The purpose of this research is to assess the release of TNT from contaminated soil under varying solution chemical conditions. In particular, influences of pH, aquatic natural organic matter, and addition of two surfactants is investigated. Uncontaminated soil was collected from a near-surface site at the Alabama Army Ammunition Plant and was artificially contaminated with TNT prior to the mobilization experiments. Results for the pH experiments show that more TNT is mobilized at neutral pH conditions than at low pH conditions. The presence of dissolved organic matter enhances the release of TNT from soil, but not by a large amount. Surfactant addition has the most significant effect on TNT mobilization.

  10. TOXCAST: A PROGRAM FOR PRIORTITIZING TOXICITY TESTING OF ENVIRONMENTAL CHEMICALS

    EPA Science Inventory

    Evaluating the potential of tens of thousands of chemicals for risk to human health and the environment is beyond the resource limits of the Environmental Protection Agency. The EPA's ToxCast program will explore alternative methods comprising computational chemistry, high-throug...

  11. The Toxicity Data Landscape for Environmental Chemicals (journal)

    EPA Science Inventory

    Thousands of chemicals are in common use but only a portion of them have undergone significant toxicological evaluation, leading to the need to prioritize the remainder for targeted testing. To address this issue, the U.S. Environmental Protection Agency (U.S. EPA) and other orga...

  12. ENVIRONMENTAL ANDROGENS AND ANTIANDROGENS: AN EXPANDING CHEMICAL UNIVERSE

    EPA Science Inventory

    Within the last ten years, awareness has grown about environmental chemicals that display antiandrogenic or androgenic activity. While studies in the early 1990s focused on pesticides that acted as androgen receptor (AR) antagonists, it soon became evident that this was not the ...

  13. Chemical Fingerprinting of Materials Developed Due To Environmental Issues

    NASA Technical Reports Server (NTRS)

    Smith, Doris A.; McCool, A. (Technical Monitor)

    2000-01-01

    This paper presents viewgraphs on chemical fingerprinting of materials developed due to environmental issues. Some of the topics include: 1) Aerospace Materials; 2) Building Blocks of Capabilities; 3) Spectroscopic Techniques; 4) Chromatographic Techniques; 5) Factors that Determine Fingerprinting Approach; and 6) Fingerprinting: Combination of instrumental analysis methods that diagnostically characterize a material.

  14. Impact of chemically contaminated sewage sludge on the collard arthropod community

    SciTech Connect

    Culliney, T.W.; Pimentel, D.; Lisk, D.J.

    1986-08-01

    Stress effects on a terrestrial arthropod community were evident in a study of collards grown in soil amended with chemically contaminated sewage sludge. Plant growth in the contaminated sludge was significantly reduced compared with growth in plots treated with relatively uncontaminated sludge from two small towns or with mature alone. Population densities of major arthropod taxa tended to be lower in plots of contaminated sludge than they were in uncontaminated sludge and manure plots. Species richness and diversity were also reduced in contaminated-sludge plots compared with those of uncontaminated sludge and manure treatments. In general, few differences were observed in plant growth and arthropod numbers between the uncontaminated-sludge treatment, or uncontaminated sludge treated with cadmium or with the insecticide dieldrin. Because cadmium and dieldrin were applied at dosages of cadmium and polychlorinated biphenyls (PCB's) found in the contaminated sludge, results suggested that these two toxins were not responsible for the effects on plants and arthropods observed in the contaminated-sludge treatment. Results of this study indicated the potential for sludge-borne contaminants to suppress growth in crop plants and reduce abundance of their associated arthropods.

  15. Chemical properties and toxicity of soils contaminated by mining activity.

    PubMed

    Agnieszka, Baran; Tomasz, Czech; Jerzy, Wieczorek

    2014-09-01

    This research is aimed at assessing the total content and soluble forms of metals (zinc, lead and cadmium) and toxicity of soils subjected to strong human pressure associated with mining of zinc and lead ores. The research area lay in the neighbourhood of the Bolesław Mine and Metallurgical Plant in Bukowno (Poland). The study obtained total cadmium concentration between 0.29 and 51.91 mg, zinc between 7.90 and 3,614 mg, and that of lead between 28.4 and 6844 mg kg(-1) of soil d.m. The solubility of the heavy metals in 1 mol dm(-3) NH4NO3 was 1-49% for zinc, 5-45% for cadmium, and <1-10% for lead. In 1 mol HCl dm(-3), the solubility of the studied metals was much higher and obtained values depending on the collection site, from 45 to 92% for zinc, from 74 to 99%, and from 79 to 99% for lead. The lower solubility of the heavy metals in 1 mol dm(-3) NH4NO3 than 1 mol HCl dm(-3) is connected with that, the ammonium nitrate has low extraction power, and it is used in determining the bioavailable (active) form of heavy metals. Toxicity assessment of the soil samples was performed using two tests, Phytotoxkit and Microtox(®). Germination index values were between 22 and 75% for Sinapis alba, between 28 and 100% for Lepidium sativum, and between 10 and 28% for Sorghum saccharatum. Depending on the studied soil sample, Vibrio fischeri luminescence inhibition was 20-96%. The sensitivity of the test organisms formed the following series: S. saccharatum > S. alba = V. fischeri > L. sativum. Significant positive correlations (p ≤ 0.05) of the total and soluble contents of the metals with luminescence inhibition in V. fischeri and root growth inhibition in S. saccharatum were found. The general trend observed was an increase in metal toxicity measured by the biotest with increasing available metal contents in soils. All the soil samples were classified into toxicity class III, which means that they are toxic and present severe danger. Biotest are a good complement to chemical analyses in the assessment of quality of soils as well as in properly managing them. PMID:24903806

  16. Chemicals of emerging concern in the Great Lakes Basin: an analysis of environmental exposures.

    PubMed

    Klecka, Gary; Persoon, Carolyn; Currie, Rebecca

    2010-01-01

    This review and statistical analysis was conducted to better understand the nature and significance of environmental exposures in the Great Lakes Basin and watershed to a variety of environmental contaminants. These contaminants of interest included current-use pesticides, pharmaceuticals, organic wastewater contaminants, alkylphenol ethoxylates, perfluorinated surfactants, flame retardants, and chlorinated paraffins. The available literature was critically reviewed and used to develop a database containing 19,611 residue values for 326 substances. In many papers, sampling locations were characterized as being downstream from municipal wastewater discharges, receiving waters for industrial facilities, areas susceptible to agricultural or urban contamination, or harbors and ports. To develop an initial assessment of their potential ecological significance, the contamination levels found were compared with currently available regulatory standards, guidelines, or criteria. This review was prepared for the IJC multi-board work group, and served as background material for an expert consultation, held in March, 2009, in which the significance of the contaminants found was discussed. Moreover, the consultation attempted to identify and assess opportunities for strengthening future actions that will protect the Great Lakes. Based on the findings and conclusions of the expert consultation, it is apparent that a wide variety of chemicals of emerging concern have been detected in environmental media (air, water, sediment, biota) from the Great Lakes Basin, although many are present at only trace levels. Although the presence of these contaminants raises concerns in the public and among the scientific community, the findings must be placed in context. Significant scientific interpretation is required to understand the extent to which these chemicals may pose a threat to the ecosystem and to human health. The ability to detect chemicals in environmental media greatly surpasses our ability to understand the implications of such findings. As advances in analytical technologies occur, it is probable that substances previously found to be non-detectable will be detected. However, their presence in environmental media should not be construed to mean that they are necessarily toxic or hazardous. Current-use pesticides are tightly regulated and extensive efforts have been made to analyze for their presence in surface waters from the Great Lakes Basin. The concentrations found in surface waters for many of the pesticides are below current regulatory criteria. However, the concentrations of certain pesticides exceeded current criteria in 6-32% of the samples analyzed. Detectable concentrations of pharmaceutical compounds were present in 34% of the surface water samples. Various prescription and non-prescription drugs were detected, most frequently at locations that were proximate to the point of discharge from wastewater treatment plants or agricultural operations. At present, there are no standards, guidelines, or criteria with which to compare these contaminant concentrations. Concentrations of alkylphenol ethoxylates and their metabolites have been well studied. All surface water nonylphenol concentrations were below US ambient water quality criteria. However, the concentrations reported for some locations exceeded Canadian guidelines for water or sediment. Only limited data were available for a wide variety of organic wastewater contaminants. Measured concentrations in Great Lakes waters were generally low. Where criteria exist for comparison, the concentrations found were generally below the associated regulatory standards. However, exceedences were noted for some classes of compounds, including phthalates and polycyclic aromatic hydrocarbons. The highest environmental concentrations were reported in biota for a number of persistent, bioaccumulative, and toxic compounds (e.g., polybrominated diphenyl ethers, perfluorinated surfactants). Various stewardship as well as government risk assessment and risk management programs have been implemented over the past years for many of these compounds. Because risk management strategies for some of these contaminants have been implemented only recently, their impact on environmental concentrations, to date, remains unclear. Current evidence suggests that the concentrations of some brominated flame retardants are trending downward, while the concentrations of others appear to be increasing. Regulatory criteria are not available for many of the chemicals of emerging concern that were detected in the Great Lakes Basin. When criteria do exist, it is important to recognize that they were developed based on the best available science at the time. As the science evolves, regulatory criteria must be reassessed in light of new findings (e.g., consideration of new endpoints and mechanisms of action). Further, there are significant scientific gaps in our ability to interpret environmental monitoring data, including the need for: (a) improving the understanding of the effects of mixtures, (b) information on use of, and the commercial life cycle of chemicals and products that contain them, (c) information on source contributions and exposure pathways, and (d) the need for thoughtful additional regulatory,environmental, and health criteria. Discharges from wastewater treatment plants were identified as an important source of contaminants to surface waters in the Great Lakes Basin. Combined sewer overflows and agricultural operations were also found to be important contributors to concentrations in surface waters. Concentrations of many of the chemicals were generally the highest in the vicinity of these sources, decline with increasing distance from sources, and were generally low or non-detectable in the open waters of the Great Lakes. PMID:20652664

  17. Health and environmental effects of complex chemical mixtures: proceedings

    SciTech Connect

    Not Available

    1985-01-01

    The Office of Health and Environmental Research (OHER) of the Department of Energy supports a broad long-term research program on human health and environmental effects from potential exposure to energy-related complex chemical mixtures. The program seeks basic mechanistic data on the effects of complex mixtures at the cellular, molecular, and whole animal levels to aid in predicting human health effects and seeks ecological data on biological and physical transformations in the mixtures, concentrations of the mixtures in various compartments of the environment, and potential routes for human exposure to these mixtures (e.g., food chain). On June 17-18, 1985, OHER held its First Annual Technical Meeting on the Complex Chemical Mixtures Program in Chicago, IL. The primary purpose of the meeting was to enable principal investigators to report the research status and accomplishments of ongoing complex chemical mixture studies supported by OHER. To help focus future research directions round table discussions were conducted.

  18. Environmental contamination by multidrug-resistant microorganisms after daily cleaning.

    PubMed

    Gavald, Laura; Pequeo, Sandra; Soriano, Ana; Dominguez, M Angeles

    2015-07-01

    We analyzed 91 samples of high-touch surfaces obtained within the first hour after daily cleaning in intensive care unit rooms occupied with patients with multidrug-resistant organisms (MDROs). We determined that 22% of high-touch surfaces in rooms with methicillin-resistant Staphylococcus aureus patients and 5% of high-touch surfaces in rooms with multiresistant Pseudomonas aeruginosa patients were colonized with the same strain as the patient. We postulated that textile cleaning wipes could be contaminated with MDROs and may contribute to its spreading within the room. PMID:25907783

  19. Metal resistant plants and phytoremediation of environmental contamination

    DOEpatents

    Meagher, Richard B.; Li, Yujing; Dhankher, Om P.

    2010-04-20

    The present disclosure provides a method of producing transgenic plants which are resistant to at least one metal ion by transforming the plant with a recombinant DNA comprising a nucleic acid encoding a bacterial arsenic reductase under the control of a plant expressible promoter, and a nucleic acid encoding a nucleotide sequence encoding a phytochelatin biosynthetic enzyme under the control of a plant expressible promoter. The invention also relates a method of phytoremediation of a contaminated site by growing in the site a transgenic plant expressing a nucleic acid encoding a bacterial arsenate reductase and a nucleic acid encoding a phytochelatin biosynthetic enzyme.

  20. Nonradiological chemical pathway analysis and identification of chemicals of concern for environmental monitoring at the Hanford Site

    SciTech Connect

    Blanton, M.L.; Cooper, A.T.; Castleton, K.J.

    1995-11-01

    Pacific Northwest`s Surface Environmental Surveillance Project (SESP) is an ongoing effort tot design, review, and conducted monitoring on and off the Hanford site. Chemicals of concern that were selected are listed. Using modeled exposure pathways, the offsite cancer incidence and hazard quotient were calculated and a retrospective pathway analysis performed to estimate what onsite concentrations would be required in the soil for each chemical of concern and other detected chemicals that would be required to obtain an estimated offsite human-health risk of 1.0E-06 cancer incidence or 1.0 hazard quotient. This analysis indicates that current nonradiological chemical contamination occurring on the site does not pose a significant offsite human-health risk; the highest cancer incidence to the offsite maximally exposed individual was from arsenic (1.76E-10); the highest hazard quotient was chromium(VI) (1.48E-04). The most sensitive pathways of exposure were surfacewater and aquatic food consumption. Combined total offsite excess cancer incidence was 2.09E-10 and estimated hazard quotient was 2.40E-04. Of the 17 identified chemicals of concern, the SESP does not currently (routinely) monitor arsenic, benzo(a)pyrene, bis(2- ethylhexyl)phthalate (BEHP), and chrysene. Only 3 of the chemicals of concern (arsenic, BEHP, chloroform) could actually occur in onsite soil at concern high enough to cause a 1.0E-06 excess cancer incidence or a 1.0 hazard index for a given offsite exposure pathway. During the retrospective analysis, 20 other chemicals were also evaluated; only vinyl chloride and thallium could reach targeted offsite risk values.

  1. [The radioecological problems of Eurasia and the sources of radioactive environmental contamination in the former USSR].

    PubMed

    Polikarpov, G G; Aarkrog, A

    1993-01-01

    There is three major sites of radioactive environmental contamination in the former USSR: the Chelyabinsk region in the Urals, Chernobyl NPP in Ukraine and Novaya Zemlya in the Arctic Ocean. The first mentioned is the most important with regard to local (potential) contamination, the last one dominates the global contamination. A number of sites and sources are less well known with regard to environmental contamination. This is thus the case for the plutonium production factories at Tomsk and Dodonovo. More information on nuclear reactors in lost or dumped submarines is also needed. From a global point of view reliable assessment of the radioactive run-off from land and deposits of nuclear waste in the Arctic Ocean are in particular pertinent. PMID:8469738

  2. Environmental contaminants in redheads wintering in coastal Louisiana and Texas

    USGS Publications Warehouse

    Michot, T.C.; Custer, T.W.; Nault, A.J.; Mitchell, C.A.

    1994-01-01

    Whole body and liver analyses indicated that wintering redheads (Aythya americana; n = 70) in coastal Louisiana (one site) and Texas (two sites) were relatively free of contamination with common trace elements, organochlorines, and hydrocarbons. Most trace elements, including As, Cr, Hg, Mg, Mn, Ni, Pb, Se, Sr, and Zn, were within background concentrations in livers; levels of B, Cd, Cu, and Fe were elevated in some specimens. Only one organochlorine, DDE, was detected in redhead carcasses, but its concentration was below reported toxic levels in waterfowl. Body burdens of aliphatic and aromatic hydrocarbons were generally low, but levels of pristane, total hydrocarbons, and the ratios of phytane:n-octadecane and pristane:n-heptadecane were indicative of possible chronic exposure to petroleum. Based on brain cholinesterase assays, redheads were not recently exposed to organophosphorous or carbamate pesticides. Of 30 elements or compounds tested for seasonal differences, only Se increased from early to late winter at one of the three sites. Eight of 57 contaminants differed among the three sites; no sex or age differences were found.

  3. Hospital ventilation standards and energy conservation: chemical contamination of hospital air. Final report

    SciTech Connect

    Rainer, D.; Michaelsen, G.S.

    1980-03-01

    In an era of increasing energy conservation consciousness, a critical reassessment of the validity of hospital ventilation and thermal standards is made. If current standards are found to be excessively conservative, major energy conservation measures could be undertaken by rebalancing and/or modification of current HVAC systems. To establish whether or not reducing ventilation rates would increase airborne chemical contamination to unacceptable levels, a field survey was conducted to develop an inventory and dosage estimates of hospital generated airborne chemical contaminants to which patients, staff, and visitors are exposed. The results of the study are presented. Emphasis is on patient exposure, but an examination of occupational exposure was also made. An in-depth assessment of the laboratory air environment is documented. Housekeeping products used in survey hospitals, hazardous properties of housekeeping chemicals and probable product composition are discussed in the appendices.

  4. CHARACTERIZATION OF CHEMICAL WASTE SITE CONTAMINATION AND DETERMINATION OF ITS EXTENT USING BIOASSAYS

    EPA Science Inventory

    The purpose of using bioassays to evaluate soils, soil elutriates, and surface and subsurface water from hazardous chemical waste sites is to provide a more direct, integrated estimate of environmental toxicity. Based on bioassay data, chemical waste sites can be ranked according...

  5. Ecological Recovery Potential of Freshwater Organisms: Consequences for Environmental Risk Assessment of Chemicals.

    PubMed

    Gergs, Andre; Classen, Silke; Strauss, Tido; Ottermanns, Richard; Brock, Theo C M; Ratte, Hans Toni; Hommen, Udo; Preuss, Thomas G

    2016-01-01

    Chemical contaminants released into the in the environment may have adverse effects on (non-target) species, populations and communities. The return of a stressed system to its pre-disturbance or other reference state, i.e. the ecological recovery, may depend on various factors related to the affected taxon, the ecosystem of concern and the type of stressor with consequences for the assessment and management of risks associated with chemical contaminants. Whereas the effects caused by short-term exposure might be acceptable to some extent, the conditions under which ecological recovery can serve as a decision criterion in the environmental risk assessment of chemical stressors remains to be evaluated. For a generic consideration of recovery in the risk assessment of chemicals, we reviewed case studies of natural and artificial aquatic systems and evaluate five aspects that might cause variability in population recovery time: (1) taxonomic differences and life-history variability, (2) factors related to ecosystem type and community processes, (3) type of disturbance, (4) comparison of field and semi-field studies, and (5) effect magnitude, i.e., the decline in population size following disturbance. We discuss our findings with regard to both retrospective assessments and prospective risk assessment. PMID:26423077

  6. Association between environmental contaminants and health outcomes in indigenous populations of the Circumpolar North

    PubMed Central

    Singh, Kavita; Bjerregaard, Peter; Man Chan, Hing

    2014-01-01

    Background Since the 1990s, research has been carried out to monitor environmental contaminants and their effects on human health in the Arctic. Although evidence shows that Arctic indigenous peoples are exposed to higher levels of contaminants and do worse on several dimensions of health compared with other populations, the contribution of such exposures on adverse outcomes is unclear. Objective The purpose of this review is to provide a synopsis of the published epidemiological literature that has examined association between environmental contaminants and health outcomes in Arctic indigenous populations. Design A literature search was conducted in OVID Medline (1946-January 2014) using search terms that combined concepts of contaminant and indigenous populations in the Arctic. No language or date restrictions were applied. The reference lists of review articles were hand-searched. Results Of 559 citations, 60 studies were relevant. The studies fell under the following categories: paediatric (n=18), reproductive health (n=18), obstetrics and gynaecology (n=9), cardiology (n=7), bone health (n=2), oncology (n=2), endocrinology (n=2) and other (n=2). All studies, except one from Arctic Finland, were either from Nunavik or Greenland. Most studies assessed polychlorinated biphenyls (n=43) and organochlorine pesticides (n=29). Fewer studies examined heavy metals, perfluorinated compounds, or polybrominated diphenyl ethers. Details of study results for each health category are provided. Conclusions It is difficult to make conclusive statements about the effects of environmental contaminants on health due to mixed results, small number of studies and studies being restricted to a small number of regions. Meta-analytical synthesis of the evidence should be considered for priority contaminants and health outcomes. The following research gaps should be addressed in future studies: association of contaminants and health in other Arctic regions (i.e. Inuvialuit Settlement Region, Nunavut, Nunatsiavut, Alaska, European North and Russian North); assessment of contaminants on chronic diseases; inclusion of clinical endpoints in assessments; and assessment of the emerging contaminants of perfluorinated compounds and polybrominated diphenyl ethers. PMID:25491153

  7. Carbon nanomaterials in clean and contaminated soils: environmental implications and applications

    NASA Astrophysics Data System (ADS)

    Riding, M. J.; Martin, F. L.; Jones, K. C.; Semple, K. T.

    2015-01-01

    The exceptional sorptive ability of carbon nanomaterials (CNMs) for hydrophobic organic contaminants (HOCs) is driven by their characteristically large reactive surface areas and highly hydrophobic nature. Given these properties, it is possible for CNMs to impact on the persistence, mobility and bioavailability of contaminants within soils, either favourably through sorption and sequestration, hence reducing their bioavailability, or unfavourably through increasing contaminant dispersal. This review considers the complex and dynamic nature of both soil and CNM physicochemical properties to determine their fate and behaviour, together with their interaction with contaminants and the soil microflora. It is argued that assessment of CNMs within soil should be conducted on a case-by-case basis and further work to assess the long-term stability and toxicity of sorbed contaminants, as well as the toxicity of CNMs themselves, is required before their sorptive abilities can be applied to remedy environmental issues.

  8. Spatial patterns of chemical contamination (metals, PAHs, PCBs, PCDDs/PCDFS) in sediments of a non-industrialized but densely populated coral atoll/small island state (Bermuda).

    PubMed

    Jones, Ross J

    2011-06-01

    There is a recognized dearth of standard environmental quality data in the wider Caribbean area, especially on coral atolls/small island states. Extensive surveys of sediment contamination (n=109 samples) in Bermuda revealed a wide spectrum of environmental quality. Zinc and especially copper levels were elevated at some locations, associated with boating (antifouling paints and boatyard discharges). Mercury contamination was surprisingly prevalent, with total levels as high as 12mg kg(-1)DW, although methyl mercury levels were quite low. PAH, PCB and PCDD/PCDF contamination was detected a several hotspots associated with road run-off, a marine landfill, and a former US Naval annexe. NOAA sediment quality guidelines were exceeded at several locations, indicating biological effects are possible, or at some locations probable. Overall, and despite lack of industrialization, anthropogenic chemicals in sediments of the atoll presented a risk to benthic biodiversity at a number of hotspots suggesting a need for sediment management strategies. PMID:21549399

  9. ENVIRONMENTAL MASS SPECTROMETRY: EMERGING CONTAMINANTS AND CURRENT ISSUES, 2006

    EPA Science Inventory

    This biennial review covers developments in Environmental Mass Spectrometry over the period of 2004-2005. A few significant references that appeared between January and February 2006 are also included. Analytical Chemistry's current policy is to limit reviews to include 100-200 s...

  10. ENVIRONMENTAL MASS SPECTROMETRY: EMERGING CONTAMINANTS AND CURRENT ISSUES, 2004 REVIEW

    EPA Science Inventory

    This review covers developments in environmental mass spectrometry over the period of 2002-2003. A few significant references that appeared between January and March 2004 are also included. This review is in keeping with a current approach of Analytical Chemistry to include onl...

  11. Environmental contaminants and the reproductive success of lake trout in the Great Lakes: an epidemiological approach

    USGS Publications Warehouse

    Mac, Michael J.; Edsall, Carol C.

    1991-01-01

    Epidemiological criteria were used to examine the influence of environmental contamination on reproductive success of lake trout (Salvelinus namaycush) in the Laurentian Great Lakes. Most of the information was obtained from lake trout eggs collected in southeastern Lake Michigan and reared in the laboratory. Two separate end points that measure reproductive success - egg hatchability and fry survival - were used in the evaluation. Strong evidence for maternally derived polychlorinated biphenyls causing reduced egg hatchability were observed for the time order, strength of association, and coherence criteria. Equally strong evidence for organic environmental contaminants, also of maternal origin, causing a swim-up fry mortality syndrome were presented for the strength of association, specificity, replication, and coherence criteria. The epidemiological approach for demonstrating cause-and-effect relations was useful because of the difficulty in demonstrating definite proof of causality between specific environmental contaminants and reproductive dysfunction in feral fish.

  12. Are chemicals in articles an obstacle for reaching environmental goals? - Missing links in EU chemical management.

    PubMed

    Molander, Linda; Breitholtz, Magnus; Andersson, Patrik L; Rybacka, Aleksandra; Rudén, Christina

    2012-10-01

    It is widely acknowledged that the management of risks associated with chemicals in articles needs to be improved. The EU environmental policy states that environmental damage should be rectified at source. It is therefore motivated that the risk management of substances in articles also takes particular consideration to those substances identified as posing a risk in different environmental compartments. The primary aim of the present study was to empirically analyze to what extent the regulation of chemicals in articles under REACH is coherent with the rules concerning chemicals in the Sewage Sludge Directive (SSD) and the Water Framework Directive (WFD). We also analyzed the chemical variation of the organic substances regulated under these legislations in relation to the most heavily used chemicals. The results show that 16 of 24 substances used in or potentially present in articles and regulated by the SSD or the WFD are also identified under REACH either as a substance of very high concern (SVHC) or subject to some restrictions. However, for these substances we conclude that there is limited coherence between the legislations, since the identification as an SVHC does not in itself encompass any use restrictions, and the restrictions in REACH are in many cases limited to a particular use, and thus all other uses are allowed. Only a minor part of chemicals in commerce is regulated and these show a chemical variation that deviates from classical legacy pollutants. This warrants new tools to identify potentially hazardous chemicals in articles. We also noted that chemicals monitored in the environment under the WFD deviate in their chemistry from the ones regulated by REACH. In summary, we argue that to obtain improved resource efficiency and a sustainable development it is necessary to minimize the input of chemicals identified as hazardous to health or the environment into articles. PMID:22858536

  13. Core sediment bacteria drive community response to anthropogenic contamination over multiple environmental gradients.

    PubMed

    Sun, Melanie Y; Dafforn, Katherine A; Johnston, Emma L; Brown, Mark V

    2013-09-01

    In this study, 454 pyrosequencing of the 16S rRNA gene was used to investigate sediment bacterial community response to contaminant disturbance across six estuaries with differing levels of 'modification'. We observed a significant influence of metal and polycyclic aromatic hydrocarbon contaminants in shaping bacterial community composition, structure and diversity, with metals being the more influential contaminant. An abundant and pervasive 'core' set of bacteria found in every sample were largely responsible for mediating community response to contamination. These 13 core operational taxonomic units were mostly comprised of Gamma-, Delta-, Alphaproteobacteria and Acidobacteria. Sediment silt and metals together explained the most variation in bacterial community composition (19.7%). Following this strong contaminant signature, salinity and temperature represented important environmental variables predicting 10.9% of community variation. While overall network connectivity measures supported the idea of an inherently diverse soil microbiome with some degree of functional redundancy, lower values observed in contaminated sediments indicate potential structural perturbations in the community from fracturing or loss of bacterial associations. The large number of unclassified sequences obtained in this study contribute to improving our understanding of environmentally relevant strains in relation to anthropogenic contamination, which have been overlooked in laboratory studies. PMID:23647974

  14. Combined Contamination and Space Environmental Effects on Solar Cells and Thermal Control Surfaces

    NASA Technical Reports Server (NTRS)

    Dever, Joyce A.; Bruckner, Eric J.; Scheiman, David A.; Stidham, Curtis R.

    1994-01-01

    For spacecraft in low Earth orbit (LEO), contamination can occur from thruster fuel, sputter contamination products and from products of silicone degradation. This paper describes laboratory testing in which solar cell materials and thermal control surfaces were exposed to simulated spacecraft environmental effects including contamination, atomic oxygen, ultraviolet radiation and thermal cycling. The objective of these experiments was to determine how the interaction of the natural LEO environmental effects with contaminated spacecraft surfaces impacts the performance of these materials. Optical properties of samples were measured and solar cell performance data was obtained. In general, exposure to contamination by thruster fuel resulted in degradation of solar absorptance for fused silica and various thermal control surfaces and degradation of solar cell performance. Fused silica samples which were subsequently exposed to an atomic oxygen/vacuum ultraviolet radiation environment showed reversal of this degradation. These results imply that solar cells and thermal control surfaces which are susceptible to thruster fuel contamination and which also receive atomic oxygen exposure may not undergo significant performance degradation. Materials which were exposed to only vacuum ultraviolet radiation subsequent to contamination showed slight additional degradation in solar absorptance.

  15. Environmental contaminants in canvasbacks wintering on San Francisco Bay, California

    USGS Publications Warehouse

    Miles, A.K.; Ohlendorf, H.M.

    1993-01-01

    The concentrations of 11 trace elements, 21 organochlorines, 13 polycyclic aromatic hydrocarbons, and 13 aliphatic hydrocarbons were determined in canvasbacks (Aythya valisineria) wintering on San Francisco Bay, California during 1988. With the exception of Se, concentrations of potentially toxic elements were low. Similarly, concentrations of most organic compounds were near or below detection limits. Aliphatic hydrocarbons, PCBs, and DDE were common, but at levels lower than those known to be harmful to waterfowl. Innocuous trace elements (Cu, Fe, and Zn), which are often associated with anthropogenic contamination, occurred at high levels. Concentrations of toxic elements were several times lower and those of benign elements were similar or greater than concentrations reported for surf scoters (Melanitta perspicillata) or greater scaup (Aythya marila) from San Francisco Bay.

  16. The effects of environmental chemicals on renal function

    PubMed Central

    Kataria, Anglina; Trasande, Leonardo; Trachtman, Howard

    2015-01-01

    The global incidence of chronic kidney disease (CKD) is increasing among individuals of all ages. Despite advances in proteomics, genomics and metabolomics, there remains a lack of safe and effective drugs to reverse or stabilize renal function in patients with glomerular or tubulointerstitial causes of CKD. Consequently, modifiable risk factors that are associated with a progressive decline in kidney function need to be identified. Numerous reports have documented the adverse effects that occur in response to graded exposure to a wide range of environmental chemicals. This Review summarizes the effects of such chemicals on four aspects of cardiorenal function: albuminuria, glomerular filtration rate, blood pressure and serum uric acid concentration. We focus on compounds that individuals are likely to be exposed to as a consequence of normal consumer activities or medical treatment, namely phthalates, bisphenol A, polyfluorinated alkyl acids, dioxins and furans, polycyclic aromatic hydrocarbons and polychlorinated biphenyls. Environmental exposure to these chemicals during everyday life could have adverse consequences on renal function and might contribute to progressive cumulative renal injury over a lifetime. Regulatory efforts should be made to limit individual exposure to environmental chemicals in an attempt to reduce the incidence of cardiorenal disease. PMID:26100504

  17. The effects of environmental chemicals on renal function.

    PubMed

    Kataria, Anglina; Trasande, Leonardo; Trachtman, Howard

    2015-10-01

    The global incidence of chronic kidney disease (CKD) is increasing among individuals of all ages. Despite advances in proteomics, genomics and metabolomics, there remains a lack of safe and effective drugs to reverse or stabilize renal function in patients with glomerular or tubulointerstitial causes of CKD. Consequently, modifiable risk factors that are associated with a progressive decline in kidney function need to be identified. Numerous reports have documented the adverse effects that occur in response to graded exposure to a wide range of environmental chemicals. This Review summarizes the effects of such chemicals on four aspects of cardiorenal function: albuminuria, glomerular filtration rate, blood pressure and serum uric acid concentration. We focus on compounds that individuals are likely to be exposed to as a consequence of normal consumer activities or medical treatment, namely phthalates, bisphenol A, polyfluorinated alkyl acids, dioxins and furans, polycyclic aromatic hydrocarbons and polychlorinated biphenyls. Environmental exposure to these chemicals during everyday life could have adverse consequences on renal function and might contribute to progressive cumulative renal injury over a lifetime. Regulatory efforts should be made to limit individual exposure to environmental chemicals in an attempt to reduce the incidence of cardiorenal disease. PMID:26100504

  18. Sampling and chemical characterization of workplace atmospheres contaminated with airborne diesel exhaust

    SciTech Connect

    Jenkins, R.A.; Griest, W.H.; Moneyhun, J.H.; Tomkins, B.A.; Ilgner, R.H.; Higgins, C.E.; Gayle, T.M.

    1988-01-01

    The chemical composition of workplace atmospheres contaminated with diesel exhaust appear to be exceedingly complex. Building to building differences occur even though the fuel source for vehicles operating in such a facility are identical. There appear to be substantial differences between the particle size distributions of workplace atmospheres and that of those sources which contaminate them. Long duration sampling tends to alter the apparent composition of the collected particle phase, and composite samples of shorter duration may enhance compositional accuracy. Diluted idling large vehicle engine exhaust is probably not a compositionally accurate surrogate for workplace atmospheres for inhalation toxicology studies.

  19. Risk assessment for chemical pickling of metals contaminated by radioactive materials.

    PubMed

    Donzella, A; Formisano, P; Giroletti, E; Zenoni, A

    2007-01-01

    In recent years, many cases of contamination of metal scraps by unwanted radioactive materials have occurred. Moreover, international organisations are evaluating the possibility to re-use or to recycle metals coming from nuclear power plants. The metal recycling industry has started to worry about radiation exposure of workers that could be in contact with contaminated metals during each manufacturing phase. Risks are strongly dependent on the radiation source features. The aim of this study is to perform risk assessment for workers involved in chemical pickling of steel coils. Monte Carlo simulations have been performed, using the MCNP package and considering coils contaminated with (60)Co, (137)Cs, (241)Am and (226)Ra. Under the most conservative conditions (coil contaminated with 1.0 kBq g(-1) of (60)Co), the dose assessment results lower than the European dose limit for the population (1 mSv y(-1)), considering a maximum number of 10 contaminated coils handled per year. The only exception concerns the case of (241)Am, for which internal contamination could be non- negligible and should be verified in the specific cases. In every case, radiation exposure risk for people standing at 50 m from the coil is widely <1 mSv y(-1). PMID:16849378

  20. Stormwater chemical contamination caused by cured-in-place pipe (CIPP) infrastructure rehabilitation activities.

    PubMed

    Tabor, Matthew L; Newman, Derrick; Whelton, Andrew J

    2014-09-16

    Cured-in-place pipe (CIPP) is becoming a popular U.S. stormwater culvert rehabilitation method. Several State transportation agencies have reported that CIPP activities can release styrene into stormwater, but no other contaminants have been monitored. CIPP's stormwater contamination potential and that of its condensate waste was characterized. Condensate completely dissolved Daphnia magna within 24 h. Condensate pH was 6.2 and its chemical oxygen demand (COD) level was 36,000 ppm. D. magna mortality (100%) occurred in 48 h, even when condensate was diluted by a factor of 10,000 and styrene was present at a magnitude less than its LC50. Condensate and stormwater contained numerous carcinogenic solvents used in resin synthesis, endocrine disrupting contaminants such as plasticizers, and initiator degradation products. For 35 days, COD levels at the culvert outlets and downstream ranged from 100 to 375 ppm and styrene was 0.01 to 7.4 ppm. Although contaminant levels generally reduced with time, styrene levels were greatest 50 ft downstream, not at the culvert outlet. Cured CIPP extraction tests confirmed that numerous contaminants other than styrene were released into the environment and their persistence and toxicity should be investigated. More effective contaminant containment and cleaner installation processes must be developed to protect the environment. PMID:25127182

  1. Study on Microbial Deposition and Contamination onto Six Surfaces Commonly Used in Chemical and Microbiological Laboratories

    PubMed Central

    Tamburini, Elena; Donegà, Valentina; Marchetti, Maria Gabriella; Pedrini, Paola; Monticelli, Cecilia; Balbo, Andrea

    2015-01-01

    The worktops in both chemical and microbiological laboratories are the surfaces most vulnerable to damage and exposure to contamination by indoor pollutants. The rate at which particles are deposited on indoor surfaces is an important parameter to determine human exposure to airborne biological particles. In contrast to what has been established for inorganic pollutants, no limit has been set by law for microbial contamination in indoor air. To our knowledge, a comparative study on the effect of surfaces on the deposition of microbes has not been carried out. An evaluation of the microbial contamination of worktop materials could be of crucial importance, both for safety reasons and for the reliability of tests and experiments that need to be carried out in non-contaminated environments. The aim of this study was to evaluate the overall microbial contamination (fungi, mesophilic and psychrophilic bacteria, staphylococci) on six widely used worktop materials in laboratories (glass, stainless steel, fine porcelain stoneware, post-forming laminate, high-performing laminate and enamel steel) and to correlate it with the characteristics of the surfaces. After cleaning, the kinetics of microbial re-contamination were also evaluated for all surfaces. PMID:26193296

  2. Study on Microbial Deposition and Contamination onto Six Surfaces Commonly Used in Chemical and Microbiological Laboratories.

    PubMed

    Tamburini, Elena; Doneg, Valentina; Marchetti, Maria Gabriella; Pedrini, Paola; Monticelli, Cecilia; Balbo, Andrea

    2015-07-01

    The worktops in both chemical and microbiological laboratories are the surfaces most vulnerable to damage and exposure to contamination by indoor pollutants. The rate at which particles are deposited on indoor surfaces is an important parameter to determine human exposure to airborne biological particles. In contrast to what has been established for inorganic pollutants, no limit has been set by law for microbial contamination in indoor air. To our knowledge, a comparative study on the effect of surfaces on the deposition of microbes has not been carried out. An evaluation of the microbial contamination of worktop materials could be of crucial importance, both for safety reasons and for the reliability of tests and experiments that need to be carried out in non-contaminated environments. The aim of this study was to evaluate the overall microbial contamination (fungi, mesophilic and psychrophilic bacteria, staphylococci) on six widely used worktop materials in laboratories (glass, stainless steel, fine porcelain stoneware, post-forming laminate, high-performing laminate and enamel steel) and to correlate it with the characteristics of the surfaces. After cleaning, the kinetics of microbial re-contamination were also evaluated for all surfaces. PMID:26193296

  3. Linking Chemical Speciation, Desorption Kinetics, and Bioavailability of U and Ni in Aged-Contaminated Sediments: A Scientific Basis for Natural Attenuation and Risk Assessment

    SciTech Connect

    Bertsch, Paul M.; Sowder, Andrew; Jackson, Brian

    2003-06-01

    The extent to which heavy metals and radionuclides pose an environmental hazard depends on their potential for release to and transport in the environment, i.e., environmental availability, and their potential for introduction into biological systems, i.e., bioavailability. Although there exists a substantial body of literature pertaining to the fate, distribution, and bioavailability of contaminant metals in model laboratory systems, few studies have examined the biogeochemical cycling of heavy metals in complex aged-contaminated soils and sediments at a fundamental level. Even fewer have coupled detailed information on chemical speciation from state-of-the-art microscopic analytical and spectroscopic techniques with macroscopic observations obtained using indirect chemical extractions, metal desorption and leaching experiments, and biological uptake and toxicity assays.

  4. Chemical and isotopic composition and potential for contamination of water in the upper Floridan aquifer, west-central Florida, 1986-1989

    SciTech Connect

    Swancar, A.; Hutchinson, C.B.

    1995-12-31

    This report describes the water quality in the Upper Floridan aquifer of west-central Florida in terms of major ion and environmental isotope concentrations, and assesses the potential for contamination of the aquifer. It also contains mineral saturation indices of ground water and a statistical analysis of ground-water chemistry data. Information and results are presented in maps showing the distribution of physical aspects of the hydrogeologic setting, chemical constituents, and potential for contamination of the Upper Floridan aquifer in west-central Florida.

  5. Rapid screening of environmental chemicals for estrogen receptor binding capacity.

    PubMed Central

    Bolger, R; Wiese, T E; Ervin, K; Nestich, S; Checovich, W

    1998-01-01

    Over the last few years, an increased awareness of endocrine disrupting chemicals (EDCs) and their potential to affect wildlife and humans has produced a demand for practical screening methods to identify endocrine activity in a wide range of environmental and industrial chemicals. While it is clear that in vivo methods will be required to identify adverse effects produced by these chemicals, in vitro assays can define particular mechanisms of action and have the potential to be employed as rapid and low-cost screens for use in large scale EDC screening programs. Traditional estrogen receptor (ER) binding assays are useful for characterizing a chemical's potential to be an estrogen-acting EDC, but they involve displacement of a radioactive ligand from crude receptor preparations at low temperatures. The usefulness of these assays for realistically determining the ER binding interactions of weakly estrogenic environmental and industrial compounds that have low aqueous solubility is unclear. In this report, we present a novel fluorescence polarization (FP) method that measures the capacity of a competitor chemical to displace a high affinity fluorescent ligand from purified, recombinant human ER-[alpha] at room temperature. The ER-[alpha] binding interactions generated for 15 natural and synthetic compounds were found to be similar to those determined with traditional receptor binding assays. We also discuss the potential to employ this FP technology to binding studies involving ER-ss and other receptors. Thus, the assay introduced in this study is a nonradioactive receptor binding method that shows promise as a high throughput screening method for large-scale testing of environmental and industrial chemicals for ER binding interactions. Images Figure 2 Figure 3 Figure 4 PMID:9721254

  6. The decay of chemical weapons agents under environmental conditions

    SciTech Connect

    McGuire, R.R.; Haas, J.S.; Eagle, R.J.

    1993-04-09

    The rate and mechanism of decay of chemical agents in the environment was studied via live agent field trials at the chemical and Biological Defence Establishment, Porton Down, UK. The plan was to deposit the agents GD (Soman), VX, and H (sulfur mustard) on separate l-m{sup 2} plots on three successive days; i.e., Tuesday through Thursday. The depositions were to be made so as to give an areal concentration of 10 g/m{sup 2}. Four felt pads of approximately 25 cm{sup 2} each were placed at the corners of each of the test plots. These were subsequently extracted and analyzed by CBDE to determine the actual agent concentration. Samples for LLNL (two different types of soil, disks of silicone rubber gasket material, and short cylinders of concrete were to be contaminated and analyzed. Results are described.

  7. Analysis of environmental contamination resulting from catastrophic incidents: part 2. Building laboratory capability by selecting and developing analytical methodologies.

    PubMed

    Magnuson, Matthew; Campisano, Romy; Griggs, John; Fitz-James, Schatzi; Hall, Kathy; Mapp, Latisha; Mullins, Marissa; Nichols, Tonya; Shah, Sanjiv; Silvestri, Erin; Smith, Terry; Willison, Stuart; Ernst, Hiba

    2014-11-01

    Catastrophic incidents can generate a large number of samples of analytically diverse types, including forensic, clinical, environmental, food, and others. Environmental samples include water, wastewater, soil, air, urban building and infrastructure materials, and surface residue. Such samples may arise not only from contamination from the incident but also from the multitude of activities surrounding the response to the incident, including decontamination. This document summarizes a range of activities to help build laboratory capability in preparation for sample analysis following a catastrophic incident, including selection and development of fit-for-purpose analytical methods for chemical, biological, and radiological contaminants. Fit-for-purpose methods are those which have been selected to meet project specific data quality objectives. For example, methods could be fit for screening contamination in the early phases of investigation of contamination incidents because they are rapid and easily implemented, but those same methods may not be fit for the purpose of remediating the environment to acceptable levels when a more sensitive method is required. While the exact data quality objectives defining fitness-for-purpose can vary with each incident, a governing principle of the method selection and development process for environmental remediation and recovery is based on achieving high throughput while maintaining high quality analytical results. This paper illustrates the result of applying this principle, in the form of a compendium of analytical methods for contaminants of interest. The compendium is based on experience with actual incidents, where appropriate and available. This paper also discusses efforts aimed at adaptation of existing methods to increase fitness-for-purpose and development of innovative methods when necessary. The contaminants of interest are primarily those potentially released through catastrophes resulting from malicious activity. However, the same techniques discussed could also have application to catastrophes resulting from other incidents, such as natural disasters or industrial accidents. Further, the high sample throughput enabled by the techniques discussed could be employed for conventional environmental studies and compliance monitoring, potentially decreasing costs and/or increasing the quantity of data available to decision-makers. PMID:24568927

  8. Sigma Chemical's environmental management system -- A case study

    SciTech Connect

    Evans, R.; Takacs, J.; Olsson, P.

    1999-07-01

    Sigma Chemical Company (Sigma) is a world leader in the production of biochemicals and reagents for life science research. The Environmental Services requirement to be able to handle a wide variety of environmental data is challenging. To meet this task Sigma turned to develop in-house a state-of-the-art environmental management system. Sigma's environmental management system is a custom developed intranet web and PC-based Windows system. The system utilizes the company's intranet to allow individuals in a web application to fill out a request form to alert Environmental Services of material ready for pick-up. Environmental Services personnel collect and contain the material and use portable handheld barcode scanners to record the information. The system is then used to track material in different storage locations as well as to build and print manifests. A costing module also allows processing and disposal charges to be issued back to the various departments from which the materials were collected. The fluid integration of this system into the Environmental Services business practices has allowed this department to streamline their operation and to process and manifest more material than thought was possible. The system is also very dynamic and easily modified to incorporate new modules to help increase efficiency.

  9. Reproductive success, developmental anomalies and environmental contaminants in double-crested cormorants (Phalacrocorax auritus)

    USGS Publications Warehouse

    Larson, J.M.; Karasov, W.H.; Sileo, L.; Stromborg, K.L.; Hanbidge, B.A.; Giesy, J.P.; Jones, P.D.; Tillitt, D.E.; Verbrugge, D.A.

    1996-01-01

    To test an association between environmental contaminants and the prevalence of congenital anomalies in colonial waterbirds, we collected representative eggs for chemical analysis from double-crested cormorant nests at colonies in Lake Michigan, Wisconsin, USA, and Lake Winnipegosis, Manitoba, Canada, and periodically revisited the nests to determine the hatching success, survivorship of hatchlings, and number of deformed hatchlings in the remainder of each clutch. Total concentrations of polychlorinated biphenyls (PCBs) in eggs were determined by capillary gas chromatography. The combined activity of planar chlorinated hydrocarbons (PCHs) in the eggs was measured in an in vitro bioassay based on the induction of ethoxyresorufin-O-deethylase (EROD) activity in rat hepatoma cells. The combined EROD induction activity was expressed as 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQ). Total concentrations of PCBs and TCDD-EQ were seven to eight times greater in eggs from Lake Michigan (7.8 ?g/g and 138 pg/g, respectively) than in those from Lake Winnipegosis (1.0 ?g/g and 19 pg/g, respectively). The proportion of eggs hatching at the Lake Michigan colony (59%) was less (p < 0.05) than at Lake Winnipegosis (70%), and the prevalence of hatchlings with deformed bills was greater (p < 0.001) at Lake Michigan (0.79 vs. 0.06%). However, within the Lake Michigan colony, concentrations of PCBs and TCDD-EQ were not correlated with either hatching success or the occurrence of deformities in nestlings.

  10. Polybrominated biphenyls in model and environmentally contaminated human blood: protein binding and immunotoxicological studies.

    PubMed

    Roboz, J; Greaves, J; Bekesi, J G

    1985-05-01

    A review and summary is given of analytical, biochemical, and immunological studies made following an immunodiagnostic investigation which revealed significant decreases in the numbers, and changes in the functional integrity, of both T-and B-lymphocytes in a group of Michigan dairy farmers exposed to polybrominated biphenyls (PBB) which had been inadvertently introduced into the food chain in 1973. A quantification technique based on selected ion monitoring of bromine anions, obtained in negative chemical ionization, permitted determination of 10-35 pg of individual PBB congener per mL serum, a 20-fold improvement over electron capture gas chromatography. An in vitro spiked system was established and shown to be a representative model of environmentally contaminated blood. Immunoprecipitation followed by mass spectrometric quantification determined that the distribution of PBB among plasma, erythrocytes, mononucleocytes and polymorphonucleocytes was 89:9:less than 1:less than 1. In plasma 80% of the PBB was bound to apolipoproteins B and A in a 3:1 ratio. No preferential absorption of PBB congeners was found in the blood compartments suggesting that changes in the relative abundances of PBB congeners observed in longitudinal studies on Michigan subjects reflect differences in excretion rates or metabolism. A repeat in 1981 of the immunodiagnostic tests conducted in 1976 revealed a virtually complete persistence of the immune dysfunctions in the Michigan farmers exposed to PBB a decade ago. PMID:2992920

  11. Polybrominated biphenyls in model and environmentally contaminated human blood: protein binding and immunotoxicological studies.

    PubMed Central

    Roboz, J; Greaves, J; Bekesi, J G

    1985-01-01

    A review and summary is given of analytical, biochemical, and immunological studies made following an immunodiagnostic investigation which revealed significant decreases in the numbers, and changes in the functional integrity, of both T-and B-lymphocytes in a group of Michigan dairy farmers exposed to polybrominated biphenyls (PBB) which had been inadvertently introduced into the food chain in 1973. A quantification technique based on selected ion monitoring of bromine anions, obtained in negative chemical ionization, permitted determination of 10-35 pg of individual PBB congener per mL serum, a 20-fold improvement over electron capture gas chromatography. An in vitro spiked system was established and shown to be a representative model of environmentally contaminated blood. Immunoprecipitation followed by mass spectrometric quantification determined that the distribution of PBB among plasma, erythrocytes, mononucleocytes and polymorphonucleocytes was 89:9:less than 1:less than 1. In plasma 80% of the PBB was bound to apolipoproteins B and A in a 3:1 ratio. No preferential absorption of PBB congeners was found in the blood compartments suggesting that changes in the relative abundances of PBB congeners observed in longitudinal studies on Michigan subjects reflect differences in excretion rates or metabolism. A repeat in 1981 of the immunodiagnostic tests conducted in 1976 revealed a virtually complete persistence of the immune dysfunctions in the Michigan farmers exposed to PBB a decade ago. PMID:2992920

  12. Sr{sup 89} -- An unnecessary contaminant of concern in SRS environmental samples

    SciTech Connect

    Holcomb, H.P.

    1993-07-28

    This report documents the technical and time bases used to conclude that the fission product, Sr{sup 89}, should no longer be considered as a contaminant of concern and an analyte in SRS environmental samples. This conclusion is the basis for hard-dollar cost savings suggestions to eliminate its analysis in F/H Areas Seepage Basin monitoring wells and in future soil, sediment and water environmental samples for which the analytical contract is to be awarded prior to October 1, 1993. Environmental Restoration should proactively pursue regulatory approval for the elimination of Sr{sup 89} as an analyte in appropriate environmental samples.

  13. The Advanced Monitoring Systems Initiative--Performance Monitoring for DOE Environmental Remediation and Contaminant Containment

    NASA Astrophysics Data System (ADS)

    Haas, W. J.; Venedam, R. J.; Lohrstorfer, C. F.; Weeks, S. J.

    2005-05-01

    The Advanced Monitoring System Initiative (AMSI) is a new approach to accelerate the development and application of advanced sensors and monitoring systems in support of Department of Energy needs in monitoring the performance of environmental remediation and contaminant containment activities. The Nevada Site Office of the National Nuclear Security Administration (NNSA) and Bechtel Nevada manage AMSI, with funding provided by the DOE Office of Environmental Management (DOE EM). AMSI has easy access to unique facilities and capabilities available at the Nevada Test Site (NTS), including the Hazardous Materials (HazMat) Spill Center, a one-of-a-kind facility built and permitted for releases of hazardous materials for training purposes, field-test detection, plume dispersion experimentation, and equipment and materials testing under controlled conditions. AMSI also has easy access to the facilities and considerable capabilities of the DOE and NNSA National Laboratories, the Special Technologies Laboratory, Remote Sensing Laboratory, Desert Research Institute, and Nevada Universities. AMSI provides rapid prototyping, systems integration, and field-testing, including assistance during initial site deployment. The emphasis is on application. Important features of the AMSI approach are: (1) customer investment, involvement and commitment to use - including definition of needs, desired mode of operation, and performance requirements; and (2) employment of a complete systems engineering approach, which allows the developer to focus maximum attention on the essential new sensing element or elements while AMSI assumes principal responsibility for infrastructure support elements such as power, packaging, and general data acquisition, control, communication, visualization and analysis software for support of decisions. This presentation describes: (1) the needs for sensors and performance monitoring for environmental systems as seen by the DOE Long Term Stewardship Science and Technology Roadmap and the Long Term Monitoring Sensors and Analytical Methods Workshop, and (2) AMSI operating characteristics and progress in addressing those needs. Topics addressed will include: vadose zone and groundwater tritium monitoring, a wireless moisture monitoring system, Cr(VI) and CCl4 monitoring using a commercially available "universal sensor platform", strontium-90 and technetium-99 monitoring, and area chemical monitoring using an array of multi-chemical sensors.

  14. The Chemical Technology Division at Argonne National Laboratory: Applying chemical innovation to environmental problems

    SciTech Connect

    1995-06-01

    The Chemical Technology Division is one of the largest technical divisions at Argonne National Laboratory, a leading center for research and development related to energy and environmental issues. Since its inception in 1948, the Division has pioneered in developing separations processes for the nuclear industry. The current scope of activities includes R&D on methods for disposing of radioactive and hazardous wastes and on energy conversion processes with improved efficiencies, lower costs, and reduced environmental impact. Many of the technologies developed by CMT can be applied to solve manufacturing as well as environmental problems of industry.

  15. Bis-(2-ethylhexyl) phthalate, an ubiquitous environmental contaminant.

    PubMed

    Griffiths, W C; Camara, P; Lerner, K S

    1985-01-01

    Bis-(2-ethylhexyl) phthalate (DEHP) is the most commonly used plasticizing agent for the widely used plastic polyvinylchloride (PVC). Consequently, this compound is found everywhere in the environment of civilization, where it is in frequent contact with every person. Blood storage bags and tubing, food wrappers, and many children's toys contain appreciable amounts of DEHP. Given this frequency of exposure, the toxic potential of the compound has become a major concern. Many workers have demonstrated its exceedingly low acute toxicity, while results from chronic exposure studies have been mixed. However, in 1982 the National Toxicology Program reported a significantly increased incidence of hepatocellular carcinoma in rats and mice exposed to high doses of DEHP over a period of two years. The significance of these studies remains in question. Bis-(2-ethylhexyl) phthalate is metabolized extensively by mammals, but reports of the direct study of the toxic effects of its metabolites are few. Efficient methods for analysis of biological samples for DEHP are available, but they are complicated by the constant presence of this compound as a contaminant. PMID:3994287

  16. Bis-(2-ethylhexyl) phthalate, an ubiquitous environmental contaminant

    SciTech Connect

    Griffiths, W.C.; Camara, P.; Lerner, K.S.

    1985-03-01

    Bis-(2-ethylhexyl) phthalate (DEHP) is the most commonly used plasticizing agent for the widely used plastic polyvinylchloride (PVC). Consequently, this compound is found everywhere in the environment of civilization, where it is in frequent contact with every person. Blood storage bags and tubing, food wrappers, and many children's toys contain appreciable amounts of DEHP. Given this frequency of exposure, the toxic potential of the compound has become a major concern. Many workers have demonstrated its exceedingly low acute toxicity, while results from chronic exposure studies have been mixed. However, in 1982 the National Toxicology Program reported a significantly increased incidence of hepatocellular carcinoma in rats and mice exposed to high doses of DEHP over a period of two years. The significance of these studies remains in question. Bis-(2-ethylhexyl) phthalate is metabolized extensively by mammals, but reports of the direct study of the toxic effects of its metabolites are few. Efficient methods for analysis of biological samples for DEHP are available, but they are complicated by the constant presence of this compound as a contaminant.

  17. Health risk implications from simultaneous exposure to multiple environmental contaminants.

    PubMed

    Genthe, B; Le Roux, W J; Schachtschneider, K; Oberholster, P J; Aneck-Hahn, N H; Chamier, J

    2013-07-01

    Water quality has deteriorated in the upper Olifants River system, South Africa, as a result of land use activities which include mining, agriculture and industries. A health risk assessment was conducted from 2009 to 2011 in the catchment to determine the possible risks local communities face from various pollutants such as microbials, heavy metals and oestrogen in the river water and vegetation. Aluminium and manganese accumulated in plants and vanadium and aluminium concentrations found in selective water samples posed significant health risks when consumed. A quantitative microbial risk assessment revealed that the combined risk of infection ranged from 1 to 26 percent with the Norovirus posing the overall greatest health risk. The anticipated disability adjusted life years resulting from drinking untreated water from these sites are in the order of 10,000 times greater than what is considered acceptable. The oestradiol activity, caused by endocrine disrupting compounds in the water, measured above the trigger value of 0.7ngL(-1). Impoverished communities in the area, who partially depend on river water for potable and domestic use, are exposed to immune-compromising metals that increase their probability of infection from waterborne diseases caused by the excess microbial pathogens in the contaminated surface water. PMID:23669339

  18. Environmental contaminants in tissues, foods, and feces of California condors

    USGS Publications Warehouse

    Wiemeyer, Stanley N.; Krynitsky, A.J.; Wilbur, S.R.

    1983-01-01

    Two wild California Condors contained moderate to high levels of DDE in their tissues. The levels found could be high enough to cause reproductive problems in adult condors, if the assumption is made that condors are as susceptible to DDE as many other species of birds of prey. Other organochlorines occurred at low levels and probably were not high enough to cause deleterious effects. Metal residues in tissues of one bird were generally low except for copper in liver and lead in bone. Normal background levels of these metals in cathartids are unknown, making interpretation of the results difficult. Organochlorine residues in biopsy samples from a captive condor were low and probably would not have an adverse effect on reproduction if the bird were used for captive breeding. Organochlorines were not detected in food items used in the supplemental feeding program, and mercury and lead residues in these items were generally low. Information is needed on current contaminant levels in natural condor prey throughout the condor range.

  19. A physical chemical screening model for anticipating widespread contamination of community water supply wells by gasoline constituents

    NASA Astrophysics Data System (ADS)

    Arey, J. Samuel; Gschwend, Philip M.

    2005-01-01

    Continuing modifications of fuels like gasoline should include evaluations of the proposed constituents for their potential to damage environmental resources such as subsurface water supplies. Consequently, we developed a screening model to estimate well water concentrations and transport times for gasoline components migrating from underground fuel tank (UFT) releases to typical at-risk community water supply wells. Representative fuel release volumes and hydrogeologic characteristics were used to parameterize the transport calculation. Subsurface degradation processes were neglected in the model in order to make risk-conservative assessments. The model was tailored to individual compounds based on their abundances in gasoline, gasoline-water partition coefficients ( Kgw), and organic matter-water partition coefficients ( Kom). Transport calculations were conducted for 20 polar and 4 nonpolar compounds found in gasoline, including methyl tert-butyl ether (MTBE) and other ether oxygenates, ethanol, methanol, and some aromatic hydrocarbons. With no calibration, the screening model successfully captured the reported magnitude of MTBE contamination of at-risk community supply wells. Such screening indicates that other oxygenates would cause similar widespread problems unless they were biodegradable. Stochastic analysis of field parameter variability concluded that community supply well contamination estimates had order-of-magnitude reliability. This indicated that such pre-manufacturing analyses may reasonably anticipate widespread environmental problems and/or inspire focused investigations into chemical properties (e.g., biodegradability) before industrial adoption of new fuel formulations.

  20. Geographically distributed classification of surface water chemical parameters influencing fate and behavior of nanoparticles and colloid facilitated contaminant transport.

    PubMed

    Hammes, Julia; Gallego-Urrea, Julián A; Hassellöv, Martin

    2013-09-15

    The current production and use of nanomaterials in consumer products have increased the concern about the possibility that these enter the rivers during their entire life cycle. Further, many aquatic contaminants undergo partitioning to the ubiquitous aquatic colloids. Here is presented the development of a set of European water types for environmental risk assessment of chemicals transported as nanovectors as is the case of environmental fate of manufactured nanoparticles and colloid-bound contaminants. A compilation of river quality geochemical data with information about multi-element composition for near 800 rivers in Europe was used to perform a principal component analysis (PCA) and define 6 contrasting water classes. With the aid of geographical information system algorithms, it was possible to analyse how the different sampling locations were predominantly represented within each European water framework directive drainage basin. These water classes and their associated Debye-Hückel parameter are determining factors to evaluate the large scale fate and behaviour of nanomaterials and other colloid-transported pollutants in the European aquatic environment. PMID:23863373

  1. Overall multi-media persistence as an indicator of potential for population-level intake of environmental contaminants

    SciTech Connect

    MacLeod, Matthew; McKone, Thomas E.

    2003-06-01

    Although it is intuitively apparent that population-level exposure to contaminants dispersed in the environment must related to the persistence of the contaminant, there has been little effort to formally quantify this link. In this paper we investigate the relationship between overall persistence in a multimedia environment and the population-level exposure as expressed by intake fraction (iF), which is the cumulative fraction of chemical emitted to the environment that is taken up by members of the population. We first confirm that for any given chemical contaminant and emission scenario the definition of iF implies that it is directly proportional to the overall multi-media persistence, P{sub OV}. We show that the proportionality constant has dimensions of time and represents the characteristic time for population intake (CTI) of the chemical from the environment. We then apply the CalTOX fate and exposure model to explore how P{sub OV} and CTI combine to determine the magnitude of iF. We find that CTI has a narrow range of possible values relative to P{sub OV} across multiple chemicals and emissions scenarios. We use data from the Canadian Environmental Protection Act Priority Substance List (PSL1) Assessments to show that exposure assessments based on empirical observation are consistent with interpretations from the model. The characteristic time for intake along different dominant exposure pathways is discussed. Results indicate that P{sub OV} derived from screening-level assessments of persistence, bioaccumulation potential, and toxicity (PBT) is a useful indicator of the potential for population-level exposure.

  2. The use of glial data in human health assessments of environmental contaminants.

    PubMed

    Kraft, Andrew D

    2015-07-01

    Central nervous system (CNS) glia (i.e., astrocytes, microglia, and oligodendrocytes) are essential for maintaining neuronal homeostasis, and they orchestrate an organized cellular response to CNS injury. In addition to their beneficial roles, studies have demonstrated that disrupted glial function can have disastrous consequences on neuronal health. While effects on neuron-supportive glia are important to consider when evaluating neurotoxicity risk, interpreting glial changes is not always straightforward, particularly when attempting to discern pro-neurotoxic phenotypes from homeostatic processes or adaptive responses. To better understand how glia have been characterized and used in human health assessments of environmental contaminants (e.g., chemicals), an evaluation of all finalized assessments conducted by the U.S. Environmental Protection Agency's influential Integrated Risk Information System (IRIS) program between 1987 and 2013 was performed. Human health assessments to date have placed a clear emphasis on the neuronal cell response to potential toxicants, although more recent assessments increasingly include descriptions of glial changes. However, these descriptions are generally brief and non-specific, and they primarily consist of documenting gliosis following overt neuronal injury. As research interest in this topic continues to increase, methods for evaluating changes in glia continue to be expanded and refined, and assessors' confidence in the reliability of these data is likely to rise. Thus, glial data are anticipated to have an increasingly influential impact on the interpretation of neurotoxicity risk and underlying mechanisms. As our understanding of the complex roles these cells play grows, this knowledge is expected to support the inclusion of more extensive and specific descriptions of glial changes, including informed interpretations of the potential impact on CNS health, in future human health assessments. PMID:25912087

  3. Invertebrates in testing of environmental chemicals: are they alternatives?

    PubMed Central

    Lagadic, L; Caquet, T

    1998-01-01

    An enlarged interpretation of alternatives in toxicology testing includes the replacement of one animal species with another, preferably a nonmammalian species. This paper reviews the potential of invertebrates in testing environmental chemicals and provides evidence of their usefulness in alternative testing methodologies. The first part of this review addresses the use of invertebrates in laboratory toxicology testing. Problems in extrapolating results obtained in invertebrates to those obtained from vertebrates are noted, suggesting that invertebrates can essentially be used in addition to rather than as replacements for vertebrates in laboratory toxicity tests. However, evaluation of the ecologic impact of environmental chemicals must include defining end points that may frequently differ from those classically used in biomedical research. In this context, alternative approaches using invertebrates may be more pertinent. The second part of the review therefore focuses on the use of invertebrates in situ to assess the environmental impact of pollutants. Advantages of invertebrates in ecotoxicologic investigation are presented for their usefulness for seeking mechanistic links between effects occurring at the individual level and consequences for higher levels of biologic organization (e.g., population and community). In the end, it is considered that replacement of vertebrates by invertebrates in ecotoxicity testing is likely to become a reality when basic knowledge of metabolic, physiologic, and developmental patterns in the latter will be sufficient to assess the effect of a given chemical through end points that could be different between invertebrates and vertebrates. PMID:9599707

  4. Predictive environmental risk assessment of chemical mixtures: a conceptual framework.

    PubMed

    Backhaus, Thomas; Faust, Michael

    2012-03-01

    Environmental risks of chemicals are still often assessed substance-by-substance, neglecting mixture effects. This may result in risk underestimations, as the typical exposure is toward multicomponent chemical "cocktails". We use the two well established mixture toxicity concepts (Concentration Addition (CA) and Independent Action (IA)) for providing a tiered outline for environmental hazard and risk assessments of mixtures, focusing on general industrial chemicals and assuming that the "base set" of data (EC50s for algae, crustaceans, fish) is available. As mixture toxicities higher than predicted by CA are rare findings, we suggest applying CA as a precautious first tier, irrespective of the modes/mechanisms of action of the mixture components. In particular, we prove that summing up PEC/PNEC ratios might serve as a justifiable CA-approximation, in order to estimate in a first tier assessment whether there is a potential risk for an exposed ecosystem if only base-set data are available. This makes optimum use of existing single substance assessments as more demanding mixture investigations are requested only if there are first indications of an environmental risk. Finally we suggest to call for mode-of-action driven analyses only if error estimations indicate the possibility for substantial differences between CA- and IA-based assessments. PMID:22260322

  5. Catchment-scale environmental controls of sediment-associated contaminant dispersal

    NASA Astrophysics Data System (ADS)

    Macklin