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1

Environmental Contaminants  

Microsoft Academic Search

hemical contamination of the environment is a pervasive, insidious side effect of human population growth and technological develop- ment. Unlike many other environmental stressors, casual observers often become aware of chemical pollutants only after some catastrophic event, such as an oil or chemical spill that kills many animals. Typically, chem- ical discharges that can be seen or smelled—or barren mine

2

Environmental contaminants  

USGS Publications Warehouse

Throughout the world, individuals and populations of herons are affected by environmental contaminants, leading to direct mortality, decreased reproductive success, or degradation of feeding habitat. Contaminants suspected or known to affect herons include organochlorine compounds, organophosphorus insecticides, trace elements, and petroleum (Parnell et al. 1988).General reviews on the effects of pesticides on birds (Risebrough 1986, 1991) and colonial water birds (Nisbet 1980) are presented elsewhere. The objective of this chapter is to review toxic effects of contaminants on herons. Unless otherwise noted, contaminant concentrations are presented as parts per million (ppm) on a wet weight (ww) basis.

Custer, T. W.

2000-01-01

3

Estrogen-like activity of seafood related to environmental chemical contaminants  

Microsoft Academic Search

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

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

2006-01-01

4

Environmental contaminants  

PubMed Central

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.

2011-01-01

5

Chemical analysis of human blood for assessment of environmental exposure to semivolatile organochlorine chemical contaminants.  

PubMed

A chemical method for the quantitative analysis of organochlorine pesticide residues present in human blood was scaled-up to provide increased sensitivity and extended to include organochlorine industrial chemicals. Whole blood samples were extracted with hexane, concentrated, and analyzed without further cleanup by gas chromatography with electron capture detection. The methodology used was validated by conducting recovery studies at 1 and 10 ng/g (ppb) levels. Screening and confirmational analyses were performed by gas chromatography/mass spectrometry on samples collected from potentially exposed residents of the Love Canal area of Niagara Falls, New York and from volunteers in the Research Triangle Park area of North Carolina for 25 specific semivolatile organochlorine contaminants including chlorobenzene and chlorotoluene congeners, hexachloro-1,3-butadiene, pesticides, and polychlorinated biphenyls as Aroclor 1260. Dichlorobenzene, hexachlorobenzene, and beta-hexachlorocyclohexane residues fell in the range of 0.1 to 26 ppb in a high percentage of both the field and volunteer blood samples analyzed. Levels of other organochlorine compounds were either non-detectable or present in sub-ppb ranges. PMID:6819409

Bristol, D W; Crist, H L; Lewis, R G; MacLeod, K E; Sovocool, G W

6

Estrogen-like activity of seafood related to environmental chemical contaminants  

PubMed Central

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.

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

2006-01-01

7

Chemical contamination of soft drinks in sealed plastic bottles by environmental stress cracking.  

PubMed

A contamination of soft drinks in sealed bottles by organic solvents is reported: closed bottles full of soft drinks were accidentally placed on a cardboard soaked with thinner and the organic fluid subsequently fissured the bottom of the bottles and penetrated into the soft drinks without any apparent leakage of the soft drinks. Experiments were carried out to simulate the process: the penetration of different organic solvents into soft drinks through the bottom of closed bottles was tested. The penetration occurred only when the closed bottles contained carbonated soft drinks (CSD), indicating that inner pressure is a necessary condition for the fissuring of the bottles. This paper discusses environmental stress cracking of polyethylene terephthalate (PET) bottles by organic solvents and migration of chemicals to CSD. Experiments were conducted to determine the conditions in which PET can be permeable to poisoning organic products. PMID:19067774

Muller, Dan; Israelsohn-Azulay, Osnat

2008-11-29

8

Biomonitoring of Environmental Status and Trends (BEST) Program: Selected Methods for Monitoring Chemical Contaminants and Their Effects in Aquatic Ecosystems.  

National Technical Information Service (NTIS)

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 effect on fish. The methods, which were selected by panels of exp...

C. J. Schmitt G. M. Dethloff

2000-01-01

9

Differential effects of environmental chemicals and food contaminants on adipogenesis, biomarker release and PPAR? activation.  

PubMed

Eleven environmental relevant chemicals were investigated for their ability to affect adipogenesis in vitro, biomarker release from adipocytes and PPAR? and ? activation. We found that butylparaben stimulated adipogenesis in 3T3-L1 adipocytes and increased release of leptin, adiponectin and resistin from the cells. Butylparaben activated PPAR? as well, which may be a mediator of the adipogenic effect. Polychlorinated biphenyl (PCB)153 also stimulate adipogenesis and biomarker release, but did not affect PPARs. The data indicates that PPAR? activating chemicals often stimulate adipocyte differentiation although PPAR? activation is neither a requirement nor a guarantee for stimulation. Four out of the eleven chemicals (bisphenol A, mono-ethylhexyl phthalate, butylparaben, PCB 153) caused increased adipogenesis. The release of adipocyte-secreted hormones was sometimes but not always correlated with the effect on adipocyte differentiation. Eight chemicals were able to cause increased leptin release. These findings strengthen the hypothesis that chemicals can interfere with pathways related to obesity development. PMID:22526026

Taxvig, Camilla; Dreisig, Karin; Boberg, Julie; Nellemann, Christine; Schelde, Ane Blicher; Pedersen, Dorthe; Boergesen, Michael; Mandrup, Susanne; Vinggaard, Anne Marie

2012-04-14

10

Environmental contaminants in human milk  

Microsoft Academic Search

Environmental contaminants can be stored in the mother's body or can be transiently present from current diet, occupational exposures or personal habits. These chemicals can be transferred prenatally to the developing fetus or postnatally from breast milk to the nursing infant. Exposures through breast milk can be substantial, especially when the mother has significant ongoing exposures or has accumulated an

HENRY A ANDERSON; MARY S WOLFF

2000-01-01

11

[Environmental contamination and children].  

PubMed

Environmental contamination is a growing problem and a major worldwide concern. Industrialization and overpopulation underlie it's first origins. Contamination has severe outcomes for the whole planet, and very particularly for mankind. But these consequences are specially ominous for childhood. Childs are more extensively exposed to contaminants than adults, for a longer period of time, and the effects are more deleterious as they act during the period of growth and development Concerning the risks associated to contaminants there is still a large paucity of data, particularly as referred to low grade exposure. PMID:16463575

Casado de Frías, Enrique

2005-01-01

12

Illicit drugs and pharmaceuticals in the environment – Forensic applications of environmental data, Part 2: Pharmaceuticals as chemical markers of faecal water contamination  

Microsoft Academic Search

This manuscript is part two of a two-part study aiming to provide a better understanding and application of environmental data not only for environmental aims but also to meet forensic objectives. In this paper pharmaceuticals were investigated as potential chemical indicators of water contamination with sewage. The monitoring program carried out in Wales revealed that some pharmaceuticals are particularly persistent

Barbara Kasprzyk-Hordern; Richard M. Dinsdale; Alan J. Guwy

2009-01-01

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

Chemical composition of burnt smell caused by accidental fires: environmental contaminants.  

PubMed

The chemical composition of the odors typical of fires has recently been deciphered. Basically the constituents are mixtures of acetophenone, benzyl alcohol, hydroxylated derivatives of benzaldehyde, methoxylated and/or alkylated phenols and naphthalene. This finding makes it possible to develop objective, practical analytic measurement methods for the burnt smell as a contribution to improving fire damage assessment and remediation monitoring. With the aid of an artificially produced burnt smell and a panel of testers the odor detection threshold of a test mixture was determined olfactometrically to 2 ?g m?³. Using a defined burnt-smell atmosphere in a test chamber, analytical methods with active sampling, the adsorbents XAD 7 and TENAX TA, and GC/MS measurement were then optimized and tested with a view to being able to carry out sensitive quantitative measurement of burnt smells. A further practical method with particular application to the qualitative characterization of this odor is based on the use of a new SPME (solid-phase microextraction) field sampler with DVB/CAR/PDMS (divinylbenzene/Carboxen™/polydimethylsiloxane) fibers. PMID:20947130

Heitmann, K; Wichmann, H; Bahadir, M; Gunschera, J; Schulz, N; Salthammer, T

2010-10-13

15

Environmental Impact Assessment Study: Leaching Of Chemical Contaminants From A Municipal Dump Site Hastsal, DELHI (Capital Of INDIA)  

Microsoft Academic Search

An Environmental Impact Study was carried mainly to assess the extent of groundwater contamination from a sanitary land fill (SLF) site, Hastsal, located in Western part of metropolitan city of Delhi. The characteristic of leachate generated from the site showed that it was acidic and yellowish in colour with very high concentration of dissolved solids, COD and BOD suggesting higher

Inamul Haq

2003-01-01

16

Environmentally contaminated families: therapeutic considerations  

SciTech Connect

The unique stress for families of exposure to environmental toxins is discussed in terms of the physical characteristics of such contaminants and resultant adaptational dilemmas, the agent or cause of the injury, and institutional responses to the contamination. Recommendations for mental health professionals working with contaminated families are presented.

Ellis, P.; Greenberg, S.; Murphy, B.C.; Reusser, J.W. (Social Research Institute of New England, Newton, MA (United States))

1992-01-01

17

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...

18

The effect of misunderstanding the chemical properties of environmental contaminants on exposure beliefs: a case involving dioxins.  

PubMed

Chemical properties of contaminants lead them to behave in particular ways in the environment and hence have specific pathways to human exposure. If residents of affected communities lack awareness of these properties, however, they could make incorrect assumptions about where and how exposure occurs. We conducted a mailed survey of 904 residents of Midland and Saginaw counties in Michigan, USA to assess to what degree residents of a community with known dioxin contamination appear to understand the hydrophobic nature of dioxins and the implications of that fact on different potential exposure pathways. Participants assessed whether various statements about dioxins were true, including multiple statements assessing beliefs about dioxins in different types of water. Participants also stated whether they believed different exposure pathways were currently significant sources of dioxin exposure in this community. A majority of residents believed that dioxins can be found in river water that has been filtered to completely remove all particulates, well water, and even city tap water, beliefs which are incongruous with the hydrophobic nature of dioxins. Mistrust of government and personal concern about dioxins predicted greater beliefs about dioxins in water. In turn, holding more beliefs about dioxins in water predicted beliefs that drinking and touching water are currently significant exposure pathways for dioxins. Ensuring that community residents' mental models accurately reflect the chemical properties of different contaminants can be important to helping them to adjust their risk perceptions and potentially their risk mitigation behaviors accordingly. PMID:23391895

Zikmund-Fisher, Brian J; Turkelson, Angela; Franzblau, Alfred; Diebol, Julia K; Allerton, Lindsay A; Parker, Edith A

2013-02-05

19

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

PubMed

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 96h 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

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

2013-09-04

20

Chemical barriers for controlling groundwater contamination  

Microsoft Academic Search

Chemical barriers are being explored as a low-cost means of controlling groundwater contamination. The barrier can intercept a contaminant plume and prevent migration by transferring contaminants from the groundwater to immobile solids. A chemical barrier can be emplaced in a landfill liner or in an aquifer cutoff wall or can be injected into a contaminant plume. Chemical barriers can be

S. J. Morrison; R. R. Spangler

1993-01-01

21

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...

22

Baseline Report of Environmental Conditions in Deepwater Dumpsite 106. Volume III. Contaminant Inputs and Chemical Characteristics - Appendix.  

National Technical Information Service (NTIS)

Because of the importance of possible heavy metal contamination, considerable emphasis was placed on measuring concentrations of a variety of metals in the water column and in key organisms. Although it does not seem that addition of contaminants at DWD-1...

1977-01-01

23

Environmental/chemical thesaurus  

SciTech Connect

The Environmental/Chemical Thesaurus approaches scientific language control problems from a multidisciplinary view. The Environmental/Biomedical Terminology Index (EBTI) was used as a base for the present thesaurus. The Environmental/Chemical Thesaurus, funded by the Environmental Protection Agency, used as its source of new terms those major terms found in 13 Environmental Protection Agency data bases. The scope of this thesaurus includes not only environmental and biomedical sciences, but also the physical sciences with emphasis placed on chemistry. Specific chemical compounds are not included; only classes of chemicals are given. To adhere to this level of classification, drugs and pesticides are identified by class rather than by specific chemical name. An attempt was also made to expand the areas of sociology and economics. Terminology dealing with law, demography, and geography was expanded. Proper names of languages and races were excluded. Geographic terms were expanded to include proper names for oceans, continents, major lakes, rivers, and islands. Political divisions were added to allow for proper names of countries and states. With such a broad scope, terminology for specific sciences does not provide for indexing to the lowest levels in plant, animal, or chemical classifications.

Shriner, C.R.; Dailey, N.S.; Jordan, A.C.; Miller, K.C.; Owens, E.T.; Rickert, L.W.

1978-06-01

24

Environmental Geochemistry of Radioactive Contamination  

NASA Astrophysics Data System (ADS)

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.

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

2003-12-01

25

Chemical sensors for environmental monitoring  

NASA Astrophysics Data System (ADS)

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.

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

1992-03-01

26

Chemical contamination of water supplies  

SciTech Connect

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.

Shy, C.M.

1985-10-01

27

Levels of chemical contaminants in nonoccupationally exposed U. S. residents  

Microsoft Academic Search

Data are presented on the levels of all chemical contaminants resulting from environmental pollution which have been found in human tissues including blood, urine, breast milk, and tissue samples obtained at autopsy. Most data results from specific surveys to determine health hazards. The roles of trace elements and recognition of the need to determine baseline levels of chemicals introduced into

J. W. Holleman; A. S. Hammons

1978-01-01

28

FIELD AND LABORATORY STUDIES OF CHEMICAL CONTAMINATION AND ENVIRONMENTALLY RELATED DISEASES IN FISH AND MOLLUSCS OF NEW ENGLAND  

EPA Science Inventory

The concentration of PCBS, PAHS, insecticides and metals in some aquatic ecosystems have reached high levels placing identified populations at risk to chemical, physical and biological agents in estuarine and open coastal areas of the United States. n the last three decades scien...

29

Environmental geochemistry of radioactive contamination.  

SciTech Connect

This report attempts to describe the geochemical foundations of the behavior of radionuclides in the environment. The information is obtained and applied in three interacting spheres of inquiry and analysis: (1) experimental studies and theoretical calculations, (2) field studies of contaminated and natural analog sites and (3) model predictions of radionuclide behavior in remediation and waste disposal. Analyses of the risks from radioactive contamination require estimation of the rates of release and dispersion of the radionuclides through potential exposure pathways. These processes are controlled by solubility, speciation, sorption, and colloidal transport, which are strong functions of the compositions of the groundwater and geomedia as well as the atomic structure of the radionuclides. The chemistry of the fission products is relatively simple compared to the actinides. Because of their relatively short half-lives, fission products account for a large fraction of the radioactivity in nuclear waste for the first several hundred years but do not represent a long-term hazard in the environment. The chemistry of the longer-lived actinides is complex; however, some trends in their behavior can be described. Actinide elements of a given oxidation state have either similar or systematically varying chemical properties due to similarities in ionic size, coordination number, valence, and electron structure. In dilute aqueous systems at neutral to basic pH, the dominant actinide species are hydroxy- and carbonato-complexes, and the solubility-limiting solid phases are commonly oxides, hydroxides or carbonates. In general, actinide sorption will decrease in the presence of ligands that complex with the radionuclide; sorption of the (IV) species of actinides (Np, Pu, U) is generally greater than of the (V) species. The geochemistry of key radionuclides in three different environments is described in this report. These include: (1) low ionic strength reducing waters from crystalline rocks at nuclear waste research sites in Sweden; (2) oxic water from the J-13 well at Yucca Mountain, Nevada, the site of a proposed repository for high level nuclear waste (HLW) in tuffaceous rocks; and (3) reference brines associated with the Waste Isolation Pilot Plant (WIPP). The transport behaviors of radionuclides associated with the Chernobyl reactor accident and the Oklo Natural Reactor are described. These examples span wide temporal and spatial scales and include the rapid geochemical and physical processes important to nuclear reactor accidents or industrial discharges as well as the slower processes important to the geologic disposal of nuclear waste. Application of geochemical information to remediating or assessing the risk posed by radioactive contamination is the final subject of this report. After radioactive source terms have been removed, large volumes of soil and water with low but potentially hazardous levels of contamination may remain. For poorly-sorbing radionuclides, capture of contaminated water and removal of radionuclides may be possible using permeable reactive barriers and bioremediation. For strongly sorbing radionuclides, contaminant plumes will move very slowly. Through a combination of monitoring, regulations and modeling, it may be possible to have confidence that they will not be a hazard to current or future populations. Abstraction of the hydrogeochemical properties of real systems into simple models is required for probabilistic risk assessment. Simplifications in solubility and sorption models used in performance assessment calculations for the WIPP and the proposed HLW repository at Yucca Mountain are briefly described.

Bryan, Charles R.; Siegel, Malcolm Dean

2003-09-01

30

Environmental contamination by carbapenem-resistant Enterobacteriaceae.  

PubMed

In the last decade, the global emergence of carbapenem resistance in Enterobacteriaceae has posed great concern to public health. Data concerning the role of environmental contamination in the dissemination of carbapenem-resistant Enterobacteriaceae (CRE) are currently lacking. Here, we aimed to examine the extent of CRE contamination in various sites in the immediate surroundings of CRE carriers and to assess the effects of sampling time and cleaning regimens on the recovery rate. We evaluated the performance of two sampling methods, CHROMAgar KPC contact plate and eSwab, for the detection of environmental CRE. eSwab was followed either by direct plating or by broth enrichment. First, 14 sites in the close vicinity of the carrier were evaluated for environmental contamination, and 5, which were found to be contaminated, were further studied. The environmental contamination decreased with distance from the patient; the bed area was the most contaminated site. Additionally, we found that the sampling time and the cleaning regimen were critical factors affecting the prevalence of environmental CRE contamination. We found that the CHROMAgar KPC contact plate method was a more effective technique for detecting environmental CRE than were eSwab-based methods. In summary, our study demonstrated that the vicinity of patients colonized with CRE is often contaminated by these organisms. Using selective contact plates to detect environmental contamination may guide cleaning efficacy and assist with outbreak investigation in an effort to limit the spread of CRE. PMID:23115260

Lerner, A; Adler, A; Abu-Hanna, J; Meitus, I; Navon-Venezia, S; Carmeli, Y

2012-10-31

31

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

SciTech Connect

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.

Jelinek, C.F.

1985-11-01

32

USEPA/WSWRD'S TREATABILITY DATABASE & COST MODELING FOR CHEMICAL CONTAMINANTS  

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...

33

Environmental chemicals targeting thyroid.  

PubMed

Thyroid hormones (THs) are required for normal brain and somatic development and for the proper regulation of physiology in both children and adults. Thyroid function is controlled by the dynamic interrelationships between the hypothalamus, the pituitary and the thyroid. These dynamic relationships maintain circulating levels of THs within a narrow range under normal conditions. Normally, there is likely to be a tight relationship between changes in circulating levels of THs and changes in TH action in various target tissues. This relationship is maintained by tissue-level mechanisms that include TH metabolism and transport. Environmental chemicals that interfere with TH signaling mechanisms (Endocrine Disrupting Chemicals, EDCs) may produce adverse effects both in the individual and in a population. Because of the complex nature of the regulation of thyroid function and TH action, the consequences of EDC exposure is also likely to be complex and our ability to understand these effects as well as to screen for potential EDCs must consider this complexity. Specifically, if there are chemicals in the environment that directly interfere with TH action through their receptors but do not affect circulating TH levels, they would not be identified as thyroid toxicants by currently applied screening methods or by epidemiological studies. The goal of this review is therefore to identify the issues that must be clearly resolved before effective risk assessment can be performed. PMID:20363719

Zoeller, Thomas R

34

Measurement of Contamination in Environmental Samples.  

National Technical Information Service (NTIS)

Contamination of environmental samples and measurement systems can be monitored through the systematic use of appropriate quality control (QC) blanks. During the last decade, a proliferation of terms for these QC samples has taken place, making the specif...

G. F. Simes J. S. Harrington

1993-01-01

35

Environmental Contaminants in Food. Volume I.  

National Technical Information Service (NTIS)

This report presents the major findings of the Office of Technology Assessment evaluation of Federal and State efforts to deal with the environmental contamination of food. Undertaken at the request of the House Committee on Interstate and Foreign Commerc...

1979-01-01

36

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...

37

Chemical Contamination of California Drinking Water  

PubMed Central

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.

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

1987-01-01

38

Investigation of Selected Potential Environmental Contaminants: Haloalcohols.  

National Technical Information Service (NTIS)

This report reviews the potential environmental hazard associated with the commercial use of a large group of chemicals that are used mostly as chemical intermediates - haloalcohols. Ten commercial compounds are covered in the report including the followi...

S. S. Lande D. A. Bogyo P. H. Howard J. Santodonato W. M. Meylan

1980-01-01

39

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...

40

Bio-assays for microchemical environmental contaminants  

PubMed Central

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

Warner, Richard E.

1967-01-01

41

Chemical fixation of arsenic in contaminated soils  

Microsoft Academic Search

Arsenic-contaminated soils have been successfully treated using fixation methods whereby chemicals are added to prevent As mobilization. However, the chemistry of the fixation process used in the field is poorly understood. We have examined one process which succeeded in immobilizing 0. I to 0.2 weight % As in soil at a 69 a old dump site through the addition of

Remy J.-C. Hennet; S. L. Brantley

1996-01-01

42

Investigation of Selected Potential Environmental Contaminants: Epoxides.  

National Technical Information Service (NTIS)

This report reviews the potential environmental and health hazards associated with the commercial use of selected epoxide compounds. Four commercial compounds are discussed in the report: ethylene oxide - primarily used as a chemical intermediate; propyle...

D. A. Bogyo J. Santodonato P. H. Howard S. S. Lande W. M. Meylan

1980-01-01

43

MEASUREMENT OF CONTAMINATION IN ENVIRONMENTAL SAMPLES  

EPA Science Inventory

Contamination of environmental samples and measurement system can be monitored through the systematic use of appropriate quality control (QC) blanks. uring the last decade, a proliferation of terms for these QC samples has taken place, making the specification of appropriate blan...

44

Environmental contaminants and learning and memory  

Microsoft Academic Search

A number of environmental contaminants are known to cause a reduction in IQ in children exposed prenatally or early in life. These effects are well documented for exposure to lead, methylmercury, polychlorinated biphenyls (PCBs), and cigarette smoke, all of which can reduce IQ by up to 5–7 IQ points. Similar effects may result from exposure to dioxins and some pesticides.

David O. Carpenter

2006-01-01

45

Setting priorities for investigating chemical contaminants in the Great Lakes  

SciTech Connect

With about one thousand chemical contaminants identified in the Great Lakes ecosystem and limited resources available for monitoring, it is necessary to decide which contaminants to monitor on a regular basis. The decision is complex because it involves tradeoffs among such values as controlling cost, protecting human health, and maintaining the quality of the aquatic ecosystem. In this study a model was developed for ranking chemicals in order of priority for monitoring in the Great Lakes. Based on multiattribute utility analysis, this quantitative model incorporates (1) decision makers' value judgements and (2) uncertainty about chemicals' toxic effects. The computer-based model was used to evaluate the extent to which such uncertainty influences the ranking of priorities. Utility assessments were conducted with six individuals representing international, multistate, and state agencies; environmental and business groups; and a research program. An experiment compared rankings based on point estimates of chemicals effects to rankings based on estimated probability distributions of effects. The results indicate that including estimates of uncertainty about chemicals toxicity can affect the order in which decision makers rank priorities for monitoring contaminants. The chemicals whose rank is most influence are those that are not currently subject to regulatory monitoring.

Bro, K.M.

1989-01-01

46

Levels of Chemical Contaminants in Nonoccupationally Exposed U.S. Residents.  

National Technical Information Service (NTIS)

Data are presented on the levels of all chemical contaminants resulting from environmental pollution which have been found in human tissues including blood, urine, breast milk, and tissue samples obtained at autopsy. Most data results from specific survey...

J. W. Holleman A. S. Hammons

1978-01-01

47

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

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 (Kützing) Czarnecki, Brachysira vitrea (Grunow) Ross in Hartley, Fragilaria rumpens (Kützing) 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

Luís, Ana Teresa; Teixeira, Paula; Almeida, Salomé Fernandes Pinheiro; Matos, João Xavier; da Silva, Eduardo Ferreira

2011-07-29

48

Decontamination of Chemical Agent Contaminated Structures and Equipment.  

National Technical Information Service (NTIS)

Operations involving chemical agents such as manufacture, loading, storage, and demilitarization have resulted in the contamination of buildings and a wide variety of processing equipment. The contamination has been caused by a number of chemical agents w...

K. R. Keehan T. S. O'Rourke W. E. Sisk

1992-01-01

49

Negative chemical ionization studied of human and food chain contamination with xenobiotic chemicals.  

PubMed Central

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 plasma, and human adipose tissue, were cleaned up by one of the following three cleanup procedures: (1) continuous liquid-liquid extraction steam distillation; (2) gel-permeation chromatography; and (3) adsorption on activated carbon followed by elution with toluene. The third procedure was used only for the examination of planar polychlorinated aromatic hydrocarbons in environmental samples. Using these techniques, we have found evidence for contamination of fish samples with polychloronaphthalenes, polychlorostyrenes, polychlorobiphenyls, polychlorodibenzofurans, and polychlorodibenzodioxins among other chemicals. The polychlorodibenzodioxins appeared only in the spectra of extracts of fish obtained from the Tittabawassee River at Midland Michigan. The polychlorodibenzofuran ions appeared in NCI mass spectra of fish that were significantly contaminated (above 2 ppm) with polychlorobiphenyls. Toxic substances occurring in human seminal plasma included pentachlorophenol, hexachlorobenzene, DDT metabolites, and polychlorobiphenyls. We have investigated toxic substances in human seminal plasma because of the apparent decrease in sperm density in U.S. males over the last 30 years. Results of screening human adipose tissue for contamination with xenobiotic chemicals have been largely coincident with result of the EPA human monitoring program. Polychlorobiphenyls, DDT metabolites, nonachlor, and chlordane have appeared in most samples examined. Detection limits for all of these chemicals were of the order of 1 ppb.

Dougherty, R C; Whitaker, M J; Smith, L M; Stalling, D L; Kuehl, D W

1980-01-01

50

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...

51

Monitoring the Natural Recovery of Hydrocarbon-Contaminated Sediments with Chemical Fingerprinting  

Microsoft Academic Search

Drs. Scott A. Stout, Gregory S. Douglas, and Allen D. Uhler are principals at NewFields Environmental Forensics Practice, LLC, in Rockland, Massachusetts. They each have over 15 years experience in the chemical characterization of petroleum and related contaminants in the environment. Their firm specializes in the application of chemical fingerprinting and other forensic tools in assessing liability associated with environmental

Scott A. Stout; Allen D. Uhler; Gregory S. Douglas

2005-01-01

52

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

PubMed

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

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

2007-12-04

53

Multimedia Contaminant Environmental Exposure Assessment (MCEA) Methodology for Coal-Fired Power Plants. Volume 2.  

National Technical Information Service (NTIS)

A coal-fired power plant assessment methodology was developed to provide the helpful and moderately accurate prediction of chemical concentrations in the environment at a reasonable cost. The Multimedia Contaminant Environmental Exposure Assessment (MCEA)...

Y. Onishi S. B. Yabusaki C. R. Cole W. E. Davis G. Whelan

1982-01-01

54

Multimedia Contaminant Environmental Exposure Assessment (MCEA) Methodology for Coal-Fired Power Plants. Volume 1.  

National Technical Information Service (NTIS)

A coal-fired power plant assessment methodology was developed to provide the helpful and moderately accurate prediction of chemical concentrations in the environment at a reasonable cost. The Multimedia Contaminant Environmental Exposure Assessment (MCEA)...

Y. Onishi S. B. Yabusaki C. R. Cole W. E. Davis G. Whelan

1982-01-01

55

Liability for Past Environmental Contamination and Privatization  

Microsoft Academic Search

This paper examines the role ofliability for past environmental contaminationin the privatization processes of Central andEastern Europe. In particular, it establishes alink between a risk-averse investor's amount ofinformation regarding the extent of pastenvironmental contamination (and its cleanupcosts) and the investor's willingness to payfor a particular enterprise, i.e., bid. As theinvestor obtains a more precise estimate of theuncertain cleanup costs, the

Dietrich Earnhart

2004-01-01

56

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

SciTech Connect

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.

Not Available

1991-04-01

57

Multimedia Contaminant Environmental Exposure Assessment (MCEA) Methodology for coal-fired power plants. Volume 2  

Microsoft Academic Search

A coal-fired power plant assessment methodology was developed to provide the helpful and moderately accurate prediction of chemical concentrations in the environment at a reasonable cost. The Multimedia Contaminant Environmental Exposure Assessment (MCEA) Methodology was developed to assess exposures of the air, soil, groundwater and surface water to chemicals released from a coal-fired power plant. The MCEA Methodology predicts chemical

Y. Onishi; S. B. Yabusaki; C. R. Cole; W. E. Davis; G. Whelan

1982-01-01

58

Multimedia contaminant environmental exposure assessment (MCEA) methodology for coal-fired power plants. Volume 1  

Microsoft Academic Search

A coal-fired power plant assessment methodology was developed to provide the helpful and moderately accurate prediction of chemical concentrations in the environment at a reasonable cost. The Multimedia Contaminant Environmental Exposure Assessment (MCEA) Methodology was developed to assess exposures of the air, soil, groundwater and surface water to chemicals released from a coal-fired power plant. The MCEA Methodology predicts chemical

Y. Onishi; S. B. Yabusaki; C. R. Cole; W. E. Davis; G. Whelan

1982-01-01

59

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

PubMed Central

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.

Solomon, Gina M; Weiss, Pilar M

2002-01-01

60

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...

61

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...

62

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

PubMed

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

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

2011-10-14

63

Proposed Identification of Environmental Tobacco Smoke as a Toxic Air Contaminant  

Microsoft Academic Search

This report provides a comprehensive assessment of the effects of environmental tobacco smoke (secondhand smoke) as of mid-2005 produced by the California Air Resources Board and Office of Environmental Health Hazard Assessment as part of the process of identifying ETS as a toxic air contaminant. Part A of the report includes information about the chemical composition of secondhand smoke and

2005-01-01

64

The problem of secondary contamination following chemical agent release  

Microsoft Academic Search

In the present issue of Critical Care, an article by Okumura and colleagues has been published on the problem of secondary contamination following chemical agent release [1]. The authors’ draw on first-hand experience [2–5] of the secondary contamination experienced during the Tokyo sarin release in 1995. This experience is important, both for the care of contaminated patients and for the

David Baker

2005-01-01

65

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 Chemistryâ??s current polic...

66

Environmental contaminants and human health in the Canadian Arctic  

Microsoft Academic Search

The third Canadian Arctic Human Health Assessment conducted under the Canadian Northern Contaminants Program (NCP), in association with the circumpolar Arctic Monitoring and Assessment Programme (AMAP), addresses concerns about possible adverse health effects in individuals exposed to environmental contaminants through a diet containing country foods. The objectives here are to: 1) provide data on changes in human contaminant concentrations and

S. G. Donaldson; J. Van Oostdam; C. Tikhonov; M. Feeley; B. Armstrong; P. Ayotte; O. Boucher; W. Bowers; L. Chan; F. Dallaire; R. Dallaire; É. Dewailly; J. Edwards; G. M. Egeland; J. Fontaine; C. Furgal; T. Leech; E. Loring; G. Muckle; T. Nancarrow; D. Pereg; P. Plusquellec; M. Potyrala; O. Receveur; R. G. Shearer

2010-01-01

67

Airborne chemical contamination of a chemically amplified resist  

NASA Astrophysics Data System (ADS)

We have found that the performance of the t-BOC/onium salt resist system is severely degraded by vapor from organic bases. This effect is very pronounced and can be observed when the coated wafers stand for 15 minutes in air containing as little as 15 parts per billion (ppb) of an organic base. The observed effect, caused by this chemical contamination, depends on the tone of the resist system. For negative tone systems the UV exposure dose, required to obtain the correct linewidth, increases. While for the positive tone system, one observes the generation of a skin at the resist-air interface. Both effects are caused by the photogenerated acid being neutralized by the airborne organic base. There are a wide variety of commonly used materials which can liberate trace amounts of volatile amines and degrade resist performance. For example, fresh paint on a laboratory wall can exhibit this detrimental effect. These effects can be minimized by storing and processing the resist coated wafers in air that has passed through a specially designed, high efficiency carbon filter. The implementation of localized air filtration, to bathe the resist in chemically pure air, enabled this resist system to operate in a manufacturing environment at a rate of 100 wafers/hour.

MacDonald, Scott A.; Clecak, Nicholas J.; Wendt, H. R.; Willson, C. Grant; Snyder, Clinton D.; Knors, C. J.; Deyoe, N. B.; Maltabes, John G.; Morrow, James R.; McGuire, Anne E.; Holmes, Steven J.

1991-06-01

68

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...

69

Characterization of chemical waste site contamination and its extent using bioassays  

SciTech Connect

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.

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

70

Multimedia environmental chemical partitioning from molecular information  

Microsoft Academic Search

The prospect of assessing the environmental distribution of chemicals directly from their molecular information was analyzed. Multimedia chemical partitioning of 455 chemicals, expressed in dimensionless compartmental mass ratios, was predicted by SimpleBox 3, a Level III Fugacity model, together with the propagation of reported uncertainty for key physicochemical and transport properties, and degradation rates. Chemicals, some registered in priority lists,

Izacar Martínez; Jordi Grifoll; Francesc Giralt; Robert Rallo

2010-01-01

71

Robotic automation of the environmental chemical laboratory  

SciTech Connect

To date, automation of the environmental chemical laboratory has been a slow and tedious affair. In many, of our domestic analytical laboratories, automation consists of no more than analytical instrumentation coupled to an autosampling device. When we look into the future environmental needs of our nation, and indeed the world, it is apparent that we will not be able to keep up with the drastically increasing sample load without automated analyses. Stricter regulatory requirements on the horizon will potentially mandate staggering changes in sampling and characterization requirements. The Contaminant Analysis Automation (CAA) Program was initiated in 1990 by the US government`s Department of Energy (DOE) to address these issues. By application of a new robotics paradigm, based on an integrated production chemistry foundation applied to analytical chemistry, the CAA will use standardized modular instruments called Standard Laboratory Modules (SLM) to provide flexible and standardized automation systems. By promoting the commercialization of this technology, CAA will provide the integrated robotics systems necessary to meet the coming remediation demands. This multilaboratory program is within the Robotics Technology Development Program (RTDP) of the Office of Technology Development (OTD).

Hollen, R.M.; Erkkila, T.H.

1994-04-01

72

Comparative Histopathological Effects of Chemically Contaminated Sediment on Marine Organisms.  

National Technical Information Service (NTIS)

Comparative pathological effects in three species of fish and six species of invertebrates were investigated using a chemically contaminated sediment from Black Rock Harbor (BRH), Connecticut, USA. Substances contained in BRH sediment are known to be geno...

G. R. Gardner P. P. Yevich

1988-01-01

73

Chemical Agents: Personal Cleaning and Disposal of Contaminated Clothing  

MedlinePLUS

... Facts About Personal Cleaning and Disposal of Contaminated Clothing Some kinds of chemical accidents or attacks may ... need to wash yourself and dispose of your clothing In most cases, emergency coordinators will let you ...

74

Chemical methods and phytoremediation of soil contaminated with heavy metals  

Microsoft Academic Search

The effects of chemical amendments (calcium carbonate (CC), steel sludge (SS) and furnace slag (FS)) on the growth and uptake of cadmium (Cd) by wetland rice, Chinese cabbage and wheat grown in a red soil contaminated with Cd were investigated using a pot experiment. The phytoremediation of heavy metal contaminated soil with vetiver grass was also studied in a field

H. M Chen; C. R Zheng; C Tu; Z. G Shen

2000-01-01

75

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...

76

LEVELS OF CHEMICAL CONTAMINANTS IN NONOCCUPATIONALLY EXPOSED U.S. RESIDENTS  

EPA Science Inventory

This report is a compilation of information on chemical contaminants resulting from environmental pollution and found in nonoccupationally exposed U.S. residents. Listed in tabular form for each of approximately 100 elements or compounds are: the tissue the compound was found in;...

77

Assessment of human contamination of estrogenic endocrine-disrupting chemicals and their risk for human reproduction  

Microsoft Academic Search

There is broad human exposure to estrogenic endocrine-disrupting chemicals (EDCs), but the data sets that exist are primarily for various environmental media such as food and water rather than the most relevant internal exposure. We have detected various kind of EDC contamination in humans including dioxin and bisphenol A (BPA) widely used for the production of plastic products. BPA was

Osamu Tsutsumi

2005-01-01

78

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, ...

79

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...

80

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 ...

81

Impact of Environmental Pollution on Contamination of Locally Grown Roughage  

Microsoft Academic Search

Vávrová M., H. Zlámalová Gargo‰ová, E. ·ucman: Impact of Environmental Pollution on Contamination of Locally Grown Roughage. Acta Vet. Brno 2002, 71: 389-400. Contamination of ration components and roughage fed to dairy cows and finishing bulls in two different agricultural ecosystems in the district of Uherské Hradi ‰tû (localities Buchlovice and Stupava) was monitored. Whereas the site Buchlovice was characterised

M. VÁVROVÁ; H. ZLÁMALOVÁ GARGO

82

Microlith Based Sorber for Removal of Environmental Contaminants  

Microsoft Academic Search

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

S. Roychoudhury; D. Walsh; J. Perry

2004-01-01

83

Emerging Environmental Contaminants: Whatâ??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...

84

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...

85

Chemical contaminants in feedlot wastes: Concentrations, effects and attenuation  

Microsoft Academic Search

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

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

2008-01-01

86

E-SMART system for in-situ detection of environmental contaminants. Quarterly progress report  

SciTech Connect

Environmental Systems Management, Analysis and Reporting neTwork (E-SMART) is a comprehensive, fully-integrated approach to in-situ, real-time detection and monitoring of environmental contaminants. E-SMART will provide new class of smart, highly sensitive, chemically-specific, in-situ, multichannel microsensors utilizing integrated optical interferometry technology, large, commercially viable set of E-SMART-compatible sensors, samplers, and network management components, and user-friendly graphical user interface for data evaluation and visualization.

NONE

1996-01-01

87

Environmental Contaminants and Human Infertility: Hypothesis or Cause for Concern?  

Microsoft Academic Search

Throughout the 1980s and 1990s the crude human birth rate (live births per 1000 population) declined, indicating reduced fertility and suggesting a potential decline in fecundity (the potential to conceive). Detection of environmental contaminants in human tissues, together with reports of a global decline in semen quality, further fueled speculation that human infertility rates are increasing and environmental toxicants are

Warren G. Foster; Michael S. Neal; Myoung-Soek Han; Miguel M. Dominguez

2008-01-01

88

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 Chemistry?s policy is to limit reviews to a maximum of 250 significant references and to mainly focus on new trends. Ev...

89

Assimilation efficiencies of chemical contaminants in aquatic invertebrates: A synthesis  

SciTech Connect

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.

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

1999-09-01

90

The effect of environmental contaminants on testicular function  

PubMed Central

Male reproductive health has deteriorated considerably in the last few decades. Nutritional, socioeconomic, lifestyle and environmental factors (among others) have been attributed to compromising male reproductive health. In recent years, a large volume of evidence has accumulated that suggests that the trend of decreasing male fertility (in terms of sperm count, quality and other changes in male reproductive health) might be due to exposure to environmental toxicants. These environmental contaminants can mimic natural oestrogens and target testicular spermatogenesis, steroidogenesis, and the function of both Sertoli and Leydig cells. Most environmental toxicants have been shown to induce reactive oxygen species, thereby causing a state of oxidative stress in various compartments of the testes. However, the molecular mechanism(s) of action of the environmental toxicants on the testis have yet to be elucidated. This review discusses the effects of some of the more commonly used environmental contaminants on testicular function through the induction of oxidative stress and apoptosis.

Mathur, Premendu Prakash; D'Cruz, Shereen Cynthia

2011-01-01

91

Environmental risk assessment of existing chemicals  

Microsoft Academic Search

Most of the existing chemicals of high priority have been released into the environment for many years. Risk assessments for\\u000a existing chemicals are now conducted within the framework of the German Existing Chemicals Program and by the EC Regulation\\u000a on Existing Substances. The environmental assessment of a chemical involves:\\u000a \\u000a \\u000a a) \\u000a \\u000a exposure assessment leading to the derivation of a predicted environmental

Jan Ahlers; Robert Diderich; Ursula Klaschka; Annette Marschner; Beatrice Schwarz-Schulz

1994-01-01

92

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

PubMed

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. PMID:20832118

Udeigwe, Theophilus K; Eze, Peter N; Teboh, Jasper M; Stietiya, Mohammed H

2010-09-15

93

Chemical tailoring of steam to remediate underground mixed waste contaminents  

DOEpatents

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.

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

1999-01-01

94

QSARs for PBPK modelling of environmental contaminants  

Microsoft Academic Search

Physiologically-based pharmacokinetic (PBPK) models are increasingly finding use in risk assessment applications of data-rich compounds. However, it is a challenge to determine the chemical-specific parameters for these models, particularly in time- and resource-limiting situations. In this regard, SARs, QSARs and QPPRs are potentially useful for computing the chemical-specific input parameters of PBPK models. Based on the frequency of occurrence of

T. Peyret; K. Krishnan

2011-01-01

95

Birth defects in wildlife: the role of environmental contaminants as inducers of reproductive and developmental dysfunction.  

PubMed

The etiology of adverse pregnancy outcomes is not well understood. Wildlife observations provide considerable evidence that environmental contaminants can play a critical role in reproductive and developmental dysfunction. Early evidence leading to a widespread awareness of the impact of environmental chemicals on surrounding wildlife was observed in the Laurentian Great Lakes. A suite of reproductive and congenital defects was identified in birds, reptiles, and mammals alike that were attributed to high concentrations of organochlorine pesticides and industrial chemicals. Due to the ubiquitous and persistent nature of many anthropogenic chemicals, these defects, including thyroid dysfunction, hatching success, egg shell thinning, and gross birth deformities, have since been identified in numerous wildlife populations across the world. Certain wildlife taxa such as amphibians are especially vulnerable to chemical perturbation and are suffering alarming population declines. Amphibian field studies have found severe hindlimb and other developmental abnormalities and it has been demonstrated that the greater the agricultural intensity, the greater the number and severity of defects in toad populations. Alligators living in contaminated lakes have shown a significant reduction in penis size and fish exposed to tributyltin have shown tail deformities and abnormal eye development. Physiological and molecular responses to chemical insult are often conserved across vertebrates, alerting scientists and medical professionals alike that greater attention needs to be paid to the roles environmental contaminants play in the etiology of congenital disorders in both humans and wildlife. PMID:20377310

Hamlin, Heather J; Guillette, Louis J

2010-04-01

96

Persistent Organic Pollutants in Vietnam: Environmental Contamination and Human Exposure  

Microsoft Academic Search

\\u000a Global contamination and toxic effects of persistent organic pollutants (POPs) have been an emerging environmental issue and\\u000a have received considerable attention during the past four decades. Although the extent of contamination by POPs has been dominant\\u000a in industrialized nations, an increasing number of recent investigations have highlighted the role of the Asia-Pacific region\\u000a as a potential source of emission for

Tu Binh Minh; Hisato Iwata; Shin Takahashi; Pham Hung Viet; Bui Cach Tuyen; Shinsuke Tanabe

97

Households contaminated by environmental tobacco smoke: sources of infant exposures  

Microsoft Academic Search

Objectives: To examine (1) whether dust and surfaces in households of smokers are contaminated with environmental tobacco smoke (ETS); (2) whether smoking parents can protect their infants by smoking outside and away from the infant; and (3) whether contaminated dust, surfaces, and air contribute to ETS exposure in infants.Design: Quasi-experiment comparing three types of households with infants: (1) non-smokers who

G E Matt; P J E Quintana; M F Hovell; J T Bernert; S Song; N Novianti; T Juarez; J Floro; C Gehrman; M Garcia; S Larson

2004-01-01

98

National Report on Human Exposure to Environmental Chemicals.  

National Technical Information Service (NTIS)

The report is a new publication that provides an ongoing assessment of the exposure of the U.S. population to environmental chemicals using biomonitoring. For this Report, an environmental chemical means a chemical compound or chemical element present in ...

2001-01-01

99

Biodegradation of Chemicals of Environmental Concern  

Microsoft Academic Search

Microorganisms in soils and waters convert many synthetic organic chemicals to inorganic products. Other compounds are transformed only by cometabolism. These microbial processes may lead to environmental detoxication, the formation of new toxicants, or the biosynthesis of persistent products. Type reactions are proposed for major categories of enzymatic transformation of synthetic chemicals in soils, natural waters, and sewage. Some organic

Martin Alexander

1981-01-01

100

Environmental Chemicals and Nervous System Dysfunction 1  

PubMed Central

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.

Damstra, Terri

1978-01-01

101

Assessment of environmental contaminant-induced lymphocyte dysfunction.  

PubMed Central

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.

Silkworth, J B; Loose, L D

1981-01-01

102

Environmental chemical exposures and human epigenetics  

PubMed Central

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.

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

2012-01-01

103

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...

104

Final Contaminant Candidate List 3 Chemicals: Screening to a PCCL.  

National Technical Information Service (NTIS)

Every five years the United States Environmental Protection Agency (EPA) is required to publish a list of contaminants (1) that are currently unregulated, (2) that are known or anticipated to occur in public water systems, and (3) which may require regula...

2009-01-01

105

Final Contaminant Candidate List 3 Chemicals: Identifying the Universe.  

National Technical Information Service (NTIS)

Every five years the United States Environmental Protection Agency (EPA) is required to publish a list of contaminants (1) that are currently unregulated, (2) that are known or anticipated to occur in public water systems, and (3) which may require regula...

2009-01-01

106

Archaeological recording and chemical stratigraphy applied to contaminated land studies.  

PubMed

The method used by archaeologists for excavation and recording of the stratigraphic evidence, within trenches with or without archaeological remains, can potentially be useful to contaminated land consultants (CLCs). The implementation of archaeological practice in contaminated land assessments (CLAs) is not meant to be an exercise in data overkill; neither should it increase costs. Rather, we suggest, that if the excavation and recording, by a trained archaeologist, of the stratigraphy is followed by in-situ chemical characterisation then it is possible that much uncertainty associated with current field sampling practices, may be removed. This is because built into the chemical stratigraphy is the temporal and spatial relationship between different parts of the site reflecting the logic behind the distribution of contamination. An archaeological recording with chemical stratigraphy approach to sampling may possibly provide 'one method fits all' for potentially contaminated land sites (CLSs), just as archaeological characterisation of the stratigraphic record provides 'one method fits all' for all archaeological sites irrespective of period (prehistoric to modern) or type (rural, urban or industrial). We also suggest that there may be practical and financial benefits to be gained by pulling together expertise and resources stemming from different disciplines, not simply at the assessment phase, but also subsequent phases, in contaminated land improvement. PMID:21962595

Photos-Jones, Effie; Hall, Allan J

2011-10-02

107

Leaching of chemical contaminants from a municipal landfill site  

SciTech Connect

In a vast majority of cases solid municipal wastes are disposed through sanitary landfill operations. However, as water percolates through such wastes, it dissolves inorganic and organic components thereby producing contaminated leachates which may constitute a large pollution potential. Such studies show that the organic contaminants emanate at high concentrations during active stages of decomposition and decrease with time as fill stabilizes but the inorganic contaminants on the other hand continue to leach for decades from a site. It is therefore pertinent that the release of chemical contaminants from each municipal landfill operation be established and documented. Such an information in turn can be valuable in the design and long term use of a landfill site. The metropolitan area of the City of Moncton comprises a population base of over 100,000 people and is situated on the bank of the Petitcodiac River. The landfill sites located on the river bank are apt to deliver their chemical contaminants into the river. This may influence the aquatic life and also constitute a potential health hazard for the public at large. The present report describes the physico-chemical data of the leachates of these landfill sites, their inorganic contents and in particular the heavy metals. In addition to leachate analysis, water and sediment samples from the river have also been analyzed for comparison.

Cyr, F.; Mehra, M.C.; Mallet, V.N.

1987-05-01

108

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

SciTech Connect

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.

Riley, R.G.; Zachara, J.M. (Pacific Northwest Lab., Richland, WA (United States))

1992-04-01

109

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

SciTech Connect

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.

Turgeon, D.D.; O'Connor, T.P. (National Oceanic and Atmospheric Administration, Rockville, MD (United States))

1991-09-01

110

Prospects for in-situ chemical treatment for contaminated soil  

SciTech Connect

Treating large volumes of contaminated soil at Superfund sites is costly. These factors have led the U.S. EPA's Superfund Program to consider in situ chemical treatment as an alternative technology for treatment of contaminated soil. Oxidation, reduction, neutralization, hydrolysis, dehalogenation, and UV/photolysis are chemical processes currently used for above-ground treatment. Temperature, physical and chemical characteristics of soil, are some operating parameters that control the effectiveness of these processes. Improvements in mixing treatment materials in soil, and methods for recovering unreacted material reaction products, are needed to allow wider application of these treatments in situ. Excalibur catalytic ozone technology, Exxon and Rio Linda cyanide destruction, and Trinity ultrasonic detoxification are innovative technologies that are being considered.

Davila, B.; Roulier, M.H.

1991-12-01

111

COMPETING FRAMES OF ENVIRONMENTAL CONTAMINATION: INFLUENCES ON GRASSROOTS COMMUNITY MOBILIZATION  

Microsoft Academic Search

This article provides an analysis of competing frames of environmental contamination in a working class neighborhood of Buffalo, New York. Through in-depth interviewing, document analysis, and participant observation, I locate and analyze emerging frames presented from local media and government sources. I argue that the most prominent frames emerged by means of local media and government, as residents referred to

Erin E. Robinson

2008-01-01

112

Environmental mercury contamination in China: Sources and impacts  

Microsoft Academic Search

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%,

L. Zhang; M. H. Wong

2007-01-01

113

Environmental surface cleanliness and the potential for contamination during handwashing  

Microsoft Academic Search

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

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

2003-01-01

114

DOCUMENTING COMPLETION OF ENVIRONMENTALLY CONTAMINATED SITES THROUGH CERTIFICATION DOCKETS  

Microsoft Academic Search

The Environmental Management Office of the U.S. Department of Energy (DOE) is responsible for remediation at sites that became contaminated by the DOE or a DOE predecessor agency. When a site is cleaned a Certification Docket, originally intended for the public audience, is compiled to document successful completion and to release the site with or without restrictions. Over several years,

Tonia Vassilowitch

115

Alterations in macrophage functions by environmental chemicals.  

PubMed Central

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.

Gardner, D E

1984-01-01

116

Prioritisation of organic contaminants in a river basin using chemical analyses and bioassays.  

PubMed

Region-specific contaminant prioritisation is an important prerequisite for sustainable and cost-effective monitoring due to the high number of different contaminants that may be present. Surface water and sediment samples from the Sava River, Croatia, were collected at four locations covering a 150-km-long river section characterised by well-defined pollution gradients. Analysis of contaminant profiles along the pollution gradients was performed by combining toxicity screening using a battery of small-scale or in vitro bioassays, which covered different modes of action, with detailed chemical characterisation based on gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). A large number of contaminants, belonging to different toxicant classes, were identified in both analysed matrices. Analyses of water samples showed that contaminants having polar character occurred in the highest concentrations, while in sediments, contributions from both non-polar and amphiphilic contaminants should be taken into account. Estimated contributions of individual contaminant classes to the overall toxicity indicated that, besides the classical pollutants, a number of emerging contaminants, including surfactants, pharmaceuticals, personal care products and plasticizers, should be taken into consideration in future monitoring activities. This work demonstrates the importance of the integrated chemical and bioanalytical approach for a systematic region-specific pollutant prioritisation. Finally, the results presented in this study confirm that hazard assessment in complex environmental matrices should be directed towards identification of key pollutants, rather than focusing on a priori selected contaminants alone. PMID:22798145

Smital, Tvrtko; Terzi?, Senka; Lon?ar, Jovica; Senta, Ivan; Žaja, Roko; Popovi?, Marta; Mikac, Iva; Tollefsen, Knut-Erik; Thomas, Kevin V; Ahel, Marijan

2012-07-15

117

Solubility, sorption, and transport of hydrophobic organic chemicals in complex mixtures. Environmental research brief  

Microsoft Academic Search

Environmental contamination problems commonly involve wastes consisting of complex mixtures of chemicals. The behavior of these mixtures has not been well understood because the primary chemodynamic properties of organic chemicals have usually been characterized in aqueous solutions which are simple in composition relative to many waste mixtures found at or near disposal\\/spill sites. The research summarized in the report focuses

P. S. C. Rao; L. S. Lee; A. L. Wood

1991-01-01

118

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...

119

Ultraviolet mini-Raman lidar for stand-off, in situ identification of chemical surface contaminants  

SciTech Connect

The Mini-Raman Lidar System (MRLS) is a portable chemical sensor that combines the spectral fingerprinting of Raman spectroscopy with the principles of solar-blind ultraviolet lidar for short-range, noncontact detection and identification of unknown substances on surfaces. The MRLS has the potential to detect contaminant films several microns thick at distances of meters and bulk quantities of substances at distances of tens of meters. The signal acquisition time is less than 1 min. The device has application to those involved in emergency response, environmental remediation, and military reconnaissance who respond initially at the site of a chemical spill or attack. (c) 2000 American Institute of Physics.

Ray, Mark D. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Sedlacek, Arthur J. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Wu, Ming [Brookhaven National Laboratory, Upton, New York 11973 (United States)

2000-09-01

120

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

USGS Publications Warehouse

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.

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

121

Alterations in macrophage functions by environmental chemicals  

Microsoft Academic Search

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

1984-01-01

122

Chemical oxidation of cable insulating oil contaminated soil.  

PubMed

Leaking cable insulating oil is a common source of soil contamination of high-voltage underground electricity cables in many European countries. In situ remediation of these contaminations is very difficult, due to the nature of the contamination and the high concentrations present. Chemical oxidation leads to partial removal of highly contaminated soil, therefore chemical oxidation was investigated and optimized aiming at a subsequent bioremediation treatment. Chemical oxidation of cable oil was studied with liquid H(2)O(2) and solid CaO(2) as well as permanganate at pH 1.8, 3.0 and 7.5. Liquid H(2)O(2) most effectively removed cable oil at pH 7.5 (24%). At pH 7.5 poor oil removal of below 5% was observed with solid CaO(2) and permanganate within 2d contact time, whereas 18% and 29% was removed at pH 1.8, respectively. A prolonged contact time of 7d showed an increased oil removal for permanganate to 19%, such improvement was not observed for CaO(2). Liquid H(2)O(2) treatment at pH 7.5 was most effective with a low acid use and was best fit to a subsequent bioremediation treatment. To further optimize in situ chemical oxidation with subsequent bioremediation the effect of the addition of the iron catalyst and a stepwise liquid H(2)O(2) addition was performed. Optimization led to a maximum of 46% cable oil removal with 1469mM of H(2)O(2), and 6.98mM Fe(II) chelated with citric acid (H(2)O(2):FeSO(4)=210:1 (molmol(-1)). The optimum delivery method was a one step addition of the iron catalyst followed by step wise addition of H(2)O(2). PMID:21571353

Xu, Jinlan; Pancras, Tessa; Grotenhuis, Tim

2011-05-14

123

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...

124

Environmental contamination of groundwater in the Gaza Strip  

NASA Astrophysics Data System (ADS)

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.

Al-Agha, M. R.

1995-03-01

125

Multimedia environmental chemical partitioning from molecular information.  

PubMed

The prospect of assessing the environmental distribution of chemicals directly from their molecular information was analyzed. Multimedia chemical partitioning of 455 chemicals, expressed in dimensionless compartmental mass ratios, was predicted by SimpleBox 3, a Level III Fugacity model, together with the propagation of reported uncertainty for key physicochemical and transport properties, and degradation rates. Chemicals, some registered in priority lists, were selected according to the availability of experimental property data to minimize the influence of predicted information in model development. Chemicals were emitted in air or water in a fixed geographical scenario representing the Netherlands and characterized by five compartments (air, water, sediments, soil and vegetation). Quantitative structure-fate relationship (QSFR) models to predict mass ratios in different compartments were developed with support vector regression algorithms. A set of molecular descriptors, including the molecular weight and 38 counts of molecular constituents were adopted to characterize the chemical space. Out of the 455 chemicals, 375 were used for training and testing the QSFR models, while 80 were excluded from model development and were used as an external validation set. Training and test chemicals were selected and the domain of applicability (DOA) of the QSFRs established by means of self-organizing maps according to structural similarity. Best results were obtained with QSFR models developed for chemicals belonging to either the class [C] and [C; O], or the class with at least one heteroatom different than oxygen in the structure. These two class-specific models, with respectively 146 and 229 chemicals, showed a predictive squared coefficient of q(2) ? 0.90 both for air and water, which respectively dropped to q(2)? 0.70 and 0.40 for outlying chemicals. Prediction errors were of the same order of magnitude as the deviations associated to the uncertainty of the physicochemical and transport properties, and degradation rates. PMID:21059471

Martínez, Izacar; Grifoll, Jordi; Giralt, Francesc; Rallo, Robert

2010-11-06

126

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

USGS Publications Warehouse

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.

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

1990-01-01

127

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

PubMed Central

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.

Bertsch, Paul M.; Seaman, John C.

1999-01-01

128

The chemical and environmental property space of REACH chemicals.  

PubMed

The European regulation on chemicals, REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals), came into force on 1 June 2007. With pre-registration complete in 2008, data for these substances may provide an overview of the expected chemical space and its characteristics. In this paper, using various in silico computation tools, we evaluate 48782 neutral organic compounds from the list to identify hazardous and safe compounds. Two different classification schemes (modified Verhaar and ECOSAR) identified between 17% and 25% of the compounds as expressing only baseline toxicity (narcosis). A smaller portion could be identified as reactive (19%) or specifically acting (2.7%), while the majority were non-assigned (61%). Overall environmental persistence, bioaccumulation and long-range transport potential were evaluated using structure-activity relationships and a multimedia fugacity-based model. A surprisingly high proportion of compounds (20%), mainly aromatic and halogenated, had a very high estimated persistence (>195 d). The proportion of compounds with a very high estimated bioconcentration or bioaccumulation factor (>5000) was substantially less (6.9%). Finally, a list was compiled of those compounds within the applicability domain of the models used, meeting both persistence and bioaccumulation criteria, and with a long-range transport potential comparable to PCB. This list of 68 potential persistent organic pollutants contained many well-known compounds (all halogenated), but notably also five fluorinated compounds that were not included in the EINECS inventory. This study demonstrates the usability of in silico tools for identification of potentially environmentally hazardous chemicals. PMID:22386455

Öberg, Tomas; Iqbal, M Sarfraz

2012-03-03

129

A signal processing framework for simultaneous detection of multiple environmental contaminants  

NASA Astrophysics Data System (ADS)

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.

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

2013-11-01

130

Meta-analysis of environmental contamination by phthalates.  

PubMed

Phthalate acid esters (PAE), commonly named phthalates, are toxics classified as endocrine-disrupting compounds; they are primarily used as additives to improve the flexibility in polyvinyl chloride. Many studies have reported the occurrence of phthalates in different environmental matrices; however, none of these studies has yet established a complete overview for those compounds in the water cycle within an urban environment. This review summarizes PAE concentrations for all environmental media throughout the water cycle, from atmosphere to receiving waters. Once the occurrences of compounds have been evaluated for each environmental compartment (urban wastewater, wastewater treatment plants, atmosphere, and the natural environment), we reviewed data in order to identify the fate of PAE in the environment and establish whether geographical and historical trends exist. Indeed, geographical and historical trends appear between Europe and other countries such as USA/Canada and China, however they remain location dependent. This study aimed at identifying both the correlations existing between environmental compartments and the processes influencing the fate and transport of these contaminants into the environment. In Europe, the concentrations measured in waterways today represent the background level of contamination, which provides evidence of a past diffuse pollution. In contrast, an increasing trend has actually been observed for developing countries, especially for China. PMID:23917738

Bergé, Alexandre; Cladière, Mathieu; Gasperi, Johnny; Coursimault, Annie; Tassin, Bruno; Moilleron, Régis

2013-08-06

131

Characterization of sea surface chemical contamination after shipping accidents.  

PubMed

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

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

2008-04-01

132

Bioluminescent bacteria as indicators of chemical contamination of coastal waters.  

PubMed

The ratio of bioluminescent to total bacteria (bioluminescent ratio, BLR) as an indicator of a variety of types of anthropogenic contamination of estuarine ecosystems was evaluated through a series of laboratory and field studies. Laboratory studies indicated that the BLR of natural bacterioplankton communities was proportionally reduced in the presence of a number of contaminants including diesel fuel and saltmarsh sediments co-contaminated with mercury and polychlorinated biphenyls (PCBs). Bioluminescent ratio inhibition was observed after short-term exposure to a contaminant suggesting a physiological rather than a population response of native microbial communities. Simulated eutrophication did not suppress the BLR. Field observations of the BLR were conducted weekly for a 2-yr period in the Skidaway River estuary, Georgia, USA. These observations revealed considerable seasonal variability associated with the BLR. Bioluminescent ratios were highest during the summer (25 +/- 15%), lower in the fall (6 +/- 5%) and spring (3 +/- 2%), and near zero during the winter. Although the BLR was not significantly correlated to salinity at a single site (Skidaway River estuary), the BLR was significantly correlated with salinity when sites within the same estuary system were compared (r2 = 0.93). Variation in BLR was not correlated to standard bacteriological indicators of water quality including total and fecal coliform bacteria. Comparison of the BLR from impacted and pristine estuarine sites during the fall suggested that anthropogenically impacted sites exhibited lower BLR than predicted from salinity versus BLR relationships developed in pristine systems. These observations suggest that the BLR could be used as a simple and reliable initial indicator of chemical contamination of estuarine systems resulting from human activity. PMID:15998855

Frischer, M E; Danforth, J M; Foy, T F; Juraske, R

2005-07-05

133

Meta-analysis of environmental contamination by alkylphenols.  

PubMed

Alkylphenols and alkylphenol ethoxylates (APE) are toxics classified as endocrine-disrupting compounds; they are used in detergents, paints, herbicides, pesticides, emulsifiers, wetting and dispersing agents, antistatic agents, demulsifiers, and solubilizers. Many studies have reported the occurrence of alkylphenols in different environmental matrices, though none of these studies have yet to establish a comprehensive overview of such compounds in the water cycle within an urban environment. This review summarizes APE concentrations for all environmental media throughout the water cycle, from the atmosphere to receiving waters. Once the occurrence of compounds has been assessed for each environmental compartment (urban wastewater, wastewater treatment plants [WWTP], atmosphere, and the natural environment), data are examined in order to understand the fate of APE in the environment and establish their geographical and historical trends. From this database, it is clear that the environment in Europe is much more contaminated by APE compared to North America and developing countries, although these APE levels have been decreasing in the last decade. APE concentrations in the WWTP effluent of developed countries have decreased by a factor of 100 over the past 30 years. This study is aimed at identifying both the correlations existing between environmental compartments and the processes that influence the fate and transport of these contaminants in the environment. In industrial countries, the concentrations observed in waterways now represent the background level of contamination, which provides evidence of a past diffuse pollution in these countries, whereas sediment analyses conducted in developing countries show an increase in APE content over the last several years. Finally, similar trends have been observed in samples drawn from Europe and North America. PMID:22864754

Bergé, Alexandre; Cladière, Mathieu; Gasperi, Johnny; Coursimault, Annie; Tassin, Bruno; Moilleron, Régis

2012-08-05

134

National Report on Human Exposure to Environmental Chemicals (3rd).  

National Technical Information Service (NTIS)

This report provides an ongoing assessment of the exposure of the U.S. population to environmental chemicals using biomonitoring. The Second National Report on Human Exposure to Environmental Chemicals (Second Report) was released in 2003 and presented bi...

2005-01-01

135

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

|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…

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

136

[Examination of the optimum condition that determines contamination for three-dimensions chemical shift imaging].  

PubMed

Magnetic resonance spectroscopy (MRS) is a useful tool for obtaining metabolic information non-invasively. However, low reducibility of MRS data, measuring biases caused by the operator, effects of relaxation time, and environmental contamination may sometimes become problematic. In this study, we examined contamination in echo time (TE) and the availability of outer volume suppression (OVS) by using the excitation and localization methods. In addition, we investigated the optimized condition for three-dimensions (3D)-chemical shift imaging (CSI) in gliomas. Contamination was dependent on resolution in the excitation and localization methods and on CSI resolution, but it was not dependent on TE. The additional installation of OVS and saturation pulse (SAT) corresponding to the target sites were extremely useful. There was concern about the influence of chemical shift, crosstalk, contamination, and no radio frequency (RF) uniformity in the marginal volume of interest (VOI). Metabolite distribution was deteriorated along the Z-axis but not in the X-Y plane. It, however, was improved by using a small voxel size in the Z-axis. PMID:22277818

Kikuchi, Chie; Inoue, Mitsuhiro

2012-01-01

137

Toxic chemical contamination of ground water: EPA oversight. Hearings before a Subcommittee of the Committee on Government Operations, House of Representatives, Ninety-Sixth Congress, Second Session July 24, 25, and September 18, 1980  

SciTech Connect

Consequences of chemical effluents from industrial sources as environmental contaminants are investigated. Industrial wastes considered include pesticides from agriculture, mining activities, leaking storage tanks, and sewers, toxic chemicals in septic tanks and road deicing salts. (PSB)

Not Available

1981-01-01

138

Assessment of environmental fate and exposure variability of organic contaminants.  

PubMed

Advanced fate assessment and its application/implication for hazardous chemicals is discussed. The spatially resolved fate assessment of chemicals has been performed using a newly developed spatially resolved multimedia environmental fate model (G-CIEMS: Grid-Catchment Integrated Modeling System) based on the geographical information system environment. The G-CIEMS modeling system has roughly 5x5-km resolution on the entire Japanese terrestrial region, combining a gridded-air and catchment-based surface and river geographic structure. A summary of the model description is given and validation results are discussed, which showed generally acceptable agreement between measured and simulated environmental levels for several tested chemicals. By applying the results of spatially resolved environmental concentration, the geographic distribution of exposure to humans is estimated, which showed that the majority of exposure occurred in Japan's land area with higher environmental concentration at the level of 99 percentiles or higher. The impact on the geographic distribution of environmental levels on human exposure from fish is analyzed based on monitoring, modeling, and several social and fisheries statistics. The results of estimation were compared to those of total diet studies. The estimated results are in a range close to the results of the total diet survey and thus basic validation was achieved in this study. However, as the nature of samples differed, more in-depth comparison may be necessary for future study. PMID:17329929

Suzuki, Noriyuki

2007-03-01

139

Environmental contaminant–mixture effects on CNS development, plasticity, and behavior  

Microsoft Academic Search

Environmental contaminants within the polycyclic aromatic hydrocarbon (PAH) and halogenated aromatic hydrocarbon class have been shown to cross the placenta exposing the fetus to the contaminant body burden of the mother. Consequently, a gestational exposure to environmental contaminants may result in increased adverse health outcomes, possibly affecting cognitive performance. Benzo(a)pyrene [B(a)P] and 2,3,7,8, tetrachlorodibenzo-p-dioxin (TCDD) are two prototypical environmental contaminants.

Deanna D Wormley; Aramandla Ramesh; Darryl B Hood

2004-01-01

140

Environmental surface cleanliness and the potential for contamination during handwashing.  

PubMed

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

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

2003-04-01

141

Geostatistics and GIS: tools for characterizing environmental contamination.  

PubMed

Geostatistics is a set of statistical techniques used in the analysis of georeferenced data that can be applied to environmental contamination and remediation studies. In this study, the 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) contamination at a Superfund site in western Maryland is evaluated. Concern about the site and its future clean up has triggered interest within the community because residential development surrounds the area. Spatial statistical methods, of which geostatistics is a subset, are becoming increasingly popular, in part due to the availability of geographic information system (GIS) software in a variety of application packages. In this article, the joint use of ArcGIS software and the R statistical computing environment are demonstrated as an approach for comprehensive geostatistical analyses. The spatial regression method, kriging, is used to provide predictions of DDE levels at unsampled locations both within the site and the surrounding areas where residential development is ongoing. PMID:15366239

Henshaw, Shannon L; Curriero, Frank C; Shields, Timothy M; Glass, Gregory E; Strickland, Paul T; Breysse, Patrick N

2004-08-01

142

Effects of environmental contaminants on reptiles: A review  

USGS Publications Warehouse

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.

Hall, R.J.

1980-01-01

143

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

PubMed Central

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.

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

1975-01-01

144

Levels of Environmental Contaminants in Human Follicular Fluid, Serum, and Seminal Plasma of Couples Undergoing In Vitro Fertilization  

Microsoft Academic Search

Environmental chemicals are thought to adversely affect human reproductive function, however there are no studies that have\\u000a explored the association between failed fertilization and exposure of both partners to environmental contaminants. Therefore,\\u000a we collected blood and follicular fluid from the female partner and seminal plasma from the male partner of 21 couples attending\\u000a an in vitro fertilization (IVF) program, in

E. V. Younglai; W. G. Foster; E. G. Hughes; K. Trim; J. F. Jarrell

2002-01-01

145

Quantifying sources of environmental contamination with Toxocara spp. eggs.  

PubMed

A rich body of work has reported levels of infection with Toxocara species in definitive hosts, and the frequency of eggs in the environment, in many different regions and situations. These have greatly increased our understanding of the relationship between egg excretion from companion and wild animals and the risk of human infection by inadvertent ingestion of eggs from soil and other environmental reservoirs. Nevertheless, it is difficult to compare studies directly because of vagaries in sampling and laboratory methods, a preponderance of prevalence rather than abundance data, and a lack of studies that systematically sample different sympatric definitive host populations. Such comparisons could be instructive, for example to determine the relative contributions of different definitive host populations and categories to environmental contamination in specified areas, and hence guide priorities for control. In this article we use estimates of host density and infection levels in the city of Bristol, UK, as a case study to evaluate the relative contribution of sympatric cats, dogs and foxes to overall environmental contamination with eggs. Results suggest that dogs, especially those less than 12 weeks of age, dominate total egg output, but that this is modified by degree of access to public areas and removal of faeces, such that foxes could take over as the primary source of eggs. Results and conclusions are likely to differ among specific locations. The general aim is to show how an improved quantitative framework for epidemiological studies of Toxocara spp. egg contamination can help to advance understanding and the effectiveness of control strategies in future. PMID:23333071

Morgan, E R; Azam, D; Pegler, K

2012-12-22

146

Non-breast milk feeding in developing countries: challenge from microbial and chemical contaminants.  

PubMed

Complementary foods based on cow's milk or gruels consumed by children in developing countries are often contaminated by bacteria during preparation, and ambient temperature rapidly increases microbial load. Thus infant formula or other weaning foods may cause diarrhea in young infants accounting for 25-33% of all deaths <5 years globally. Environmental chemicals such as metals (As, Pb, Cu) and nitrates can cause vomiting/diarrhea. Polychlorinated biphenyls derived from plastics, present in formula and/or breast milk, are endocrine disruptors (the potential threats are not fully quantifiable). The prevailing view is that benefits from breastfeeding outweigh potential risks. PMID:22699772

Weisstaub, Gerardo; Uauy, Ricardo

2012-06-06

147

Potential for portal detection of human chemical and biological contamination  

NASA Astrophysics Data System (ADS)

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.

Settles, Gary S.; McGann, William J.

2001-08-01

148

Environmental review of options for managing radioactively contaminated carbon steel  

SciTech Connect

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.

NONE

1996-10-01

149

Chemical and radiation environmental risk management: differences, commonalities, and challenges.  

PubMed

Driven by differing statutory mandates and programmatic separation of regulatory responsibilities between federal, state, and tribal agencies, distinct chemical and radiation risk management strategies have evolved. In the field this separation poses real challenges since many of the major environmental risk management decisions we face today require the evaluation of both types of risks. Over the last decade, federal, state, and tribal agencies have continued to discuss their different approaches and explore areas where their activities could be harmonized. The current framework for managing public exposures to chemical carcinogens has been referred to as a "bottom up approach." Risk between 10(-4) and 10(-6) is established as an upper bound goal. In contrast, a "top down" approach that sets an upper bound dose limit and couples with site specific As Low As Reasonably Achievable Principle (ALARA), is in place to manage individual exposure to radiation. While radiation risk are typically managed on a cumulative basis, exposure to chemicals is generally managed on a chemical-by-chemical, medium-by-medium basis. There are also differences in the nature and size of sites where chemical and radiation contamination is found. Such differences result in divergent management concerns. In spite of these differences, there are several common and practical concerns among radiation and chemical risk managers. They include 1) the issue of cost for site redevelopment and long-term stewardship, 2) public acceptance and involvement, and 3) the need for flexible risk management framework to address the first two issues. This article attempts to synthesize key differences, opportunities for harmonization, and challenges ahead. PMID:10859777

Tran, N L; Locke, P A; Burke, T A

2000-04-01

150

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

Microsoft Academic Search

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,

Theophilus K. Udeigwe; Peter N. Eze; Jasper M. Teboh; Mohammed H. Stietiya

2011-01-01

151

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

PubMed

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

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

152

Environmental contaminants in wild mink in the Northwest Territories, Canada.  

PubMed

As a top trophic level species that readily bioaccumulates environmental pollutants, the mink (Mustela vison) is considered to be a sensitive indicator of ecosystem health. Here we report on the first 2 years of a 4-year program established to examine organochlorine and heavy metal residues in wild mink from western Northwest Territories (NWT), Canada. Tissue samples taken from up to 24 mink harvested from each of five sites in 1991-92 and 1992-93 were analyzed for residues of a suite of 63 organochlorines in fat and liver samples, including 43 polychlorinated biphenyl (PCB) congeners and 20 pesticides, and residues of 10 heavy metals in liver and kidney samples. Overall, contaminant levels were low in comparison with levels in other mink studied in North America. Sigma PCB residues (sum of 43 congeners) ranged from a mean of 5.32 ng/g wet weight in the livers of Inuvik mink (the most northerly collection site) to 27.67 ng/g in mink from Fort Smith (the most southerly collection site). There appeared to be no differences in organochlorine burden between sexes. Heavy metal residues were also comparatively low, with the exception of total mercury, which was at moderate levels (community means of 1.16-3.30 micrograms/g wet wt. in liver samples). There was a distinct trend of decreasing organochlorine contaminant burdens with increasing latitude, but no trend in heavy metal burdens was evident. There was a doubling of mean sigma PCB levels in Inuvik mink from 5.32 ng/g wet weight in 1991-92 to 10.69 ng/g in 1992-93. Population indices derived from age and sex ratios of the harvest, coupled with comparatively low levels of contaminants, suggest little or no effects on mink reproduction or population health as a result of these contaminants. Long-range atmospheric transport is probably the major source of most of the contaminants. Additional collections will further elucidate spatial and temporal trends in contaminant levels in NWT mink. PMID:7892580

Poole, K G; Elkin, B T; Bethke, R W

1995-01-15

153

Stability of earth dam contaminated by chemical transport  

NASA Astrophysics Data System (ADS)

When chemicals are introduced into the oil, they affect soil properties such as hydraulic conductivity and stress-strain behavior. In this study, several chloride concentrations are varied from 0 to 20 per cent to analyse the effect of chemicals on soil properties. A series of laboratory triaxial tests are performed on the cylindrical specimens of sand-bentonite mixture with different sodium chloride contents (5, 10, 15 per cent) by Nannapaneni. Deformation (elastic modulus, E) and strength (cohesion, c, and angle of friction, ) parameters are obtained from the triaxial tests as functions of confining pressure and sodium chloride concentrations, and variations of parameters are incorporated into stability analysis.The stress-strain-strength behaviour based on the above strength parameters is introduced in a finite element procedure with a modified residual flow procedure (RFP). By integrating a slope stability procedure in the finite element method, the stability with time of earth dam contaminated by sodium chloride is examined. It is found that increasing sodium chloride concentration for the soil considered increases stability. However, the procedure is general and can allow stability analysis under the influence of other chemical which may lead to decrease in stability.

Ahn, Taebong; Desai, Chandra S.

1999-12-01

154

Human health risks due to consumption of chemically contaminated fishery products.  

PubMed Central

A small proportion of fishery products contaminated with appreciable amounts of potentially hazardous inorganic and organic contaminants from natural and environmental sources seem to pose the greatest potential for toxicity to consumers of fishery products in the United States. Health risks due to chemicals (e.g., modest changes in the overall risk of cancer, subtle deficits of neurological development in fetuses and children) are difficult to measure directly in people exposed to low levels. Immunocompetence may increase cancer risk. Inferences about the potential magnitude of these problems must be based on the levels of specific chemical present, observations of human populations and experimental animals exposed to relatively high doses, and theories about the likely mechanisms of action of specific intoxicants and the population distribution of sensitivity of human exposure. Lognormal distributions were found to provide good descriptions of the pattern of variation of contaminant concentrations among different species and geographic areas; this variability offers a solution for reduction of exposure through restricting harvest of aquatic animals from certain sites and by excluding certain species. Available information suggest that risks are not generally of high magnitude; nevertheless, their control will significantly improve public health.(ABSTRACT TRUNCATED AT 250 WORDS)

Ahmed, F E; Hattis, D; Wolke, R E; Steinman, D

1993-01-01

155

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

PubMed

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

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

2009-04-16

156

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

PubMed

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

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

1996-08-01

157

Food contaminants  

Microsoft Academic Search

With the increasing use of a large variety of chemicals, opportunities for contamination of food are becoming greater. Food may be involved following some accidental occurrence or from more general environmental contamination. Three examples are given: an outbreak of paralysis in Morocco involved 10,000 people who had ingested food adulterated with triorthocresyl phosphate; an epidemic of jaundice in London followed

G. Kazantzis

1974-01-01

158

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

NASA Astrophysics Data System (ADS)

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.

Dean, Kim R.; Kishkovich, Oleg P.

2000-06-01

159

Chemical contaminants, lymphocystis, and dermal sarcoma in walleyes spawning in the Thames River, Ontario  

Microsoft Academic Search

Chemical contaminants may play a role in the etiology of external skin lesions on walleyes Stizostedion vitreum in the Great Lakes. We examined the population of walleyes spawning in the Thames River, Ontario, for skin lesions, and compared contaminant levels in walleyes with conspicuous lesions to contaminant levels in visibly normal walleyes. In 1987, 9% of postspawning downstream migrants exhibited

IAN R. SMITH; ALLAN F. JOHNSON; DONALD MACLENNAN; HAROLD MANSON

1992-01-01

160

Chemical Contaminants, Lymphocystis, and Dermal Sarcoma in Walleyes Spawning in the Thames River, Ontario  

Microsoft Academic Search

Chemical contaminants may play a role in the etiology of external skin lesions on walleyes Stizostedion vitreum in the Great Lakes. We examined the population of walleyes spawning in the Thames River, Ontario, for skin lesions, and compared contaminant levels in walleyes with conspicuous lesions to contaminant levels in visibly normal walleyes. In 1987, 9% of postspawning downstream migrants exhibited

Ian R. Smith; Allan F. Johnson; Donald MacLennan; Harold Manson

1992-01-01

161

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

National Technical Information Service (NTIS)

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 thos...

J. McLachlan

1998-01-01

162

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...

163

Road A Chemical Basin: Environmental information document  

SciTech Connect

The Road A Chemical Basin at the Savannah River Plant was closed and backfilled in 1973. It received miscellaneous radioactive and chemical aqueous waste. Four groundwater monitoring wells indicate no elevated levels of analytes in the groundwater. The closure options considered for this waste site are waste removal and closure, no waste removal and closure, and no action. Modeling calculations were made to determine the risks to human population for the three postulated closure options. An ecological assessment was conducted to predict the environmental impacts on aquatic and terrestrial biota. The relative costs for each of the closure options were estimated. Maximum health risk due to radioactive materials (/sup 238/U) is about 8.0E-06 excess health effects per year, for the no action option. The no waste removal and closure and waste removal and closure options reduce the calculated risk to about 1.2E-06 and 1.2E-08 HE/yr, respectively. The maximum calculated impact due to noncarcinogenic materials (lead) is 0.54 ADI fraction. The maximum calculated ADI fraction for lead after the period of institutional control is 4.1 E-04 for the reclaimed-farmland pathway for the no action option. Public risk attributable to atmospheric releases of chemical and radioactive constituents is minimal. For all years and options modeled, the noncarcinogenic risks calculated were zero except for the year of excavation, which had an ADI fraction of 1.41E-09. The maximum individual radiological health risk for the waste removal and closure option is small (6.97E-12 HE/yr). The radiological health effects for the no waste removal and closure and no action options are zero. The ecological assessment shows that the effects of any closure activities on river water quality and wildlife would be insignificant. The cost estimates show that the waste removal and closure option is the most expensive ($4,000,000). 41 refs., 13 figs., 41 tabs.

Pickett, J.B.; Muska, C.F.; Bledsoe, H.W.

1987-03-01

164

Chemical markers of human waste contamination: analysis of urobilin and pharmaceuticals in source waters.  

PubMed

Giving public water authorities another tool to monitor and measure levels of human waste contamination of waters simply and rapidly would enhance public protection. Most of the methods used today detect such contamination by quantifying microbes occurring in feces in high enough densities that they can be measured easily. However, most of these microbes, for example E. coli, do not serve as specific markers for any one host species and many can have origins other than feces. As an alternative, chemicals shed in feces and urine might be used to detect human waste contamination of environmental waters. One potential chemical marker of human waste is the compound urobilin. Urobilin is one of the final by-products of hemoglobin breakdown. Urobilin is excreted in both the urine and feces from many mammals, particularly humans. Source waters from 21 sites in New England, Nevada, and Michigan were extracted using hydrophilic-lipophilic balance (HLB) cartridges and then analyzed by high performance liquid chromatography-electrospray mass spectrometry (HPLC-ES-MS). As a marker of human waste, urobilin was detected in many of the source waters at concentrations ranging from not detectable to 300 ng L(-1). Besides urobilin, azithromycin, an antibiotic widely prescribed for human use only in the US, was also detected in many of these waters, with concentrations ranging from not detectable to 77 ng L(-1). This methodology, using both urobilin and azithromycin (or any other human-use pharmaceutical) could be used to give public water authorities a definitive method for tracing the sources of human waste contamination. The analysis and detection of urobilin in surface waters by HPLC-ES-MS has not been previously reported in the peer-reviewed literature. PMID:16604237

Jones-Lepp, T L

2006-03-10

165

Chemical Contamination of the Lower Rio Grande near Laredo, TX  

NASA Astrophysics Data System (ADS)

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.

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

2006-12-01

166

Waste reduction by separation of contaminated soils during environmental restoration  

Microsoft Academic Search

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL\\/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil

J. A. Roybal; R. Conway; B. Galloway; E. Vinsant; P. Slavin; D. Guerin

1998-01-01

167

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...

168

Biosupported Bimetallic Pd Au Nanocatalysts for Dechlorination of Environmental Contaminants  

SciTech Connect

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.

De Corte, S.; Fitts, J.; Hennebel, T.; Sabbe, T.; Bliznuk, V.; Verschuere, S.; van der Lelie, D.; Verstraete, W.; Boon, N.

2011-08-30

169

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

PubMed

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

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

2012-06-09

170

Effects of environmental contaminants on snapping turtles of a tidal wetland  

Microsoft Academic Search

Snapping turtles (Chelydra serpentina) were collected from a brackish-water and a nearly freshwater area in the contaminated Hackensack Meadowlands of New Jersey and an uncontaminated freshwater area in Maryland to determine the effects of environmental contaminants on a resident wetland species. No turtles were observed or caught in the Meadowlands at two trapping sites that were the most heavily contaminated

P. H. Albers; L. Sileo; B. M. Mulhern

1986-01-01

171

Regulation of Environmental Contaminants in Drinking Water: State Methods and Problems  

Microsoft Academic Search

Risk assessment methodologies form the basis for deriving guidelines for environmental contaminants in drinking water. A state may have to set, on an emergency basis, an interim guideline for a drinking water contaminant for which only limited data are available. Additional national drinking water standards will be useful for state regulatory agencies, because maximum contaminant levels (MCLs) are legally enforceable,

Kirpal S. Sidhu

1992-01-01

172

Selected chemical contaminants in surface sediments of Commencement Bay and the Tacoma waterways, Washington, USA (revised)  

SciTech Connect

Eight metals, 21 organic priority pollutants, and 11 other contaminants and contaminant-related sediment characteristics were measured in surface sediments (upper 2 cm) at 21 locations in Commencement Bay and the Tacoma Waterways, Washington. Summary statistics were calculated and statistical approaches were applied to subsets of the data to classify sediment contamination. High concentrations of some contaminants appeared to be related to proximity to sources of contaminants. Depositional vectors and chemical-adsorption processes may also influence the spatial distribution of sediment contamination in the study area.

Schults, D.W.; Ferraro, S.P.; Ditsworth, G.R.; Sercu, K.A.

1987-01-01

173

Thyroid hormone metabolism and environmental chemical exposure  

PubMed Central

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/F’s and dioxin like-PCBs (dl-PCB’s) 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’, 5,5’tetrathyroxine (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.

2012-01-01

174

In situ chemical fixation of arsenic-contaminated soils: an experimental study.  

PubMed

This paper reports the results of an experimental study testing a low-cost in situ chemical fixation method designed to reclaim arsenic-contaminated subsurface soils. Subsurface soils from several industrial sites in southeastern U.S. were contaminated with arsenic through heavy application of herbicide containing arsenic trioxide. The mean concentrations of environmentally available arsenic in soils collected from the two study sites, FW and BH, are 325 mg/kg and 900 mg/kg, respectively. The soils are sandy loams with varying mineralogical and organic contents. The previous study [Yang L, Donahoe RJ. The form, distribution and mobility of arsenic in soils contaminated by arsenic trioxide, at sites in Southeast USA. Appl Geochem 2007;22:320-341] indicated that a large portion of the arsenic in both soils is associated with amorphous aluminum and iron oxyhydroxides and shows very slow release against leaching by synthetic precipitation. The soil's amorphous aluminum and iron oxyhydroxides content was found to have the most significant effect on its ability to retain arsenic. Based on this observation, contaminated soils were reacted with different treatment solutions in an effort to promote the formation of insoluble arsenic-bearing phases and thereby decrease the leachability of arsenic. Ferrous sulfate, potassium permanganate and calcium carbonate were used as the reagents for the chemical fixation solutions evaluated in three sets of batch experiments: (1) FeSO(4); (2) FeSO(4) and KMnO(4); (3) FeSO(4), KMnO(4) and CaCO(3). The optimum treatment solutions for each soil were identified based on the mobility of arsenic during sequential leaching of treated and untreated soils using the fluids described in EPA Method 1311 [USEPA. Method 1311: toxicity characteristic leaching procedure. Test methods for evaluating solid waste, physical/chemical methods. 3rd ed. Washington, DC: U.S. Environmental Protection Agency, Office of Solid Waste. U.S. Government Printing Office; 1992] toxic characteristics leaching procedure (TCLP) and EPA Method 1312 [USEPA. Method 1312: synthetic precipitation leaching procedure. Test methods for evaluating solid waste, physical/chemical methods. 3rd ed. Washington, DC: U.S. Environmental Protection Agency, Office of Solid Waste. U.S. Government Printing Office; 1994] synthetic precipitation leaching procedure (SPLP). Both FW and BH soils showed significant decreases in arsenic leachability for all three treatment solutions, compared to untreated soil. While soils treated with solution (3) showed the best results with subsequent TCLP sequential leaching, SPLP sequential leaching of treated soils indicated that lowest arsenic mobility was obtained using treatment solution (1). Treatment solution (1) with only FeSO(4) is considered the best choice for remediation of arsenic-contaminated soil because SPLP sequential leaching better simulates natural weathering. Analysis of treated soils produced no evidence of newly-formed arsenic-bearing phases in either soil after treatment. Sequential chemical extractions of treated soils indicate that surface complexation of arsenic on ferric hydroxide is the major mechanism for the fixation process. PMID:17673278

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

2007-07-27

175

Chemically enhanced phytoextraction of lead-contaminated soils.  

PubMed

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

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

2012-08-01

176

Sources of Organic Contaminants in Solvents and Implications for Geochemistry and Environmental Forensics: An Example from Local Vendors in Nigeria  

Microsoft Academic Search

Two solvents, n-hexane and petroleum ether, commonly used for extract analysis of geological and environmental samples and purchased from chemical suppliers in Nigeria, were analyzed using gas chromatography-mass spectrometry for quantitative determination of organic background contaminants. Series of n-alkanes and n-alk-1-enes in the carbon number range of nC16–nC26, the latter with an even predominance (Cmax 16 and 18) were observed.

Bassey O. Ekpo; Orok E. Oyo-Ita; Daniel R. Oros; Bernd R. T. Simoneit

2012-01-01

177

Environmental chemical mutagens and genetic risks: Lessons from radiation genetics  

SciTech Connect

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.

Sankaranarayanan, K. [Leiden Univ. (Netherlands)

1996-12-31

178

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

PubMed

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 ?p.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 ha

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

2011-01-01

179

Physical and chemical factors affecting microbial biomass and activity in contaminated subsurface riverine sediments.  

PubMed

Over 80 years of direct discharge of industrial effluents into the Mahoning River, located in northeastern Ohio, USA, has led to the accumulation of a wide variety of pollutants within its sediments. This study examined the physical and chemical parameters, including lipophilic pollutants, affecting microbial activity and biomass in subsurface (10-40 cm horizon) sediments. Microbial biomass was higher in anthropogenically contaminated sediments, and step-wise linear regression showed that approximately 82% of the variation in microbial biomass could be explained by total hexane extractable hydrocarbons, sediment particle size, and water content. There was no correlation between microbial activity and biomass. Independent variables influencing anaerobic activity were temperature and water holding capacity. The results of this study indicate that freshwater, sedimentary anaerobic microbial communities respond to a range of environmental parameters, many of which influence subsurface river sediments, and that lipophilic pollutants, when present, can cause increases in total microbial biomass. PMID:16699563

Mosher, Jennifer J; Findlay, Robert H; Johnston, Carl G

2006-05-01

180

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...

181

Environmental release of chemicals and reproductive ecology.  

PubMed Central

Reproductive ecology is defined as "the study of causes and mechanisms of the effects of environmental risk factors on reproductive health and the methods of their prevention and management." Major areas of concern, within the purview of this paper, relate to adverse pregnancy outcomes, effects on target tissues in the male and the female, and alterations in the control and regulatory mechanisms of reproductive processes. Teratogenic potential of chemicals, released as a result of accidents and catastrophes, is of critical significance. Congenital Minamata disease is due to transplacental fetal toxicity caused by accidental ingestion of methyl mercury. Generalized disorders of ectodermal tissue following prenatal exposure to polychlorinated biphenyls have been reported in Taiwan and Japan. The Bhopal gas disaster, a catastrophic industrial accident, was due to a leak of toxic gas, methyl isocyanate (MIC), in the pesticide manufacturing process. The outcome of pregnancy was studied in female survivors of MIC exposure. The spontaneous abortion rate was nearly four times more common in the affected areas as compared to the control area (24.2% versus 5.6%; p < 0.0001). Furthermore, while stillbirth rate was found to be similar in the affected and control areas, the perinatal and neonatal mortality rates were observed to be higher in the affected area. The rate of congenital malformations in the affected and control areas did not show any significant difference. Chromosomal aberrations and sister chromatid exchange (SCE) frequencies were investigated in human survivors of exposure. The observed SCE frequencies in control and exposed groups indicated that mutagenesis has been induced. Strategies for the management, prediction, and preventability of such disasters are outlined.

Bajaj, J S; Misra, A; Rajalakshmi, M; Madan, R

1993-01-01

182

Chemical Immobilization of Lead, Zinc, and Cadmium in Smelter-Contaminated Soils Using Biosolids and Rock Phosphate  

Microsoft Academic Search

Chemical immobilization, an in situ remediation method where phate fertilizer for chemical remediation of Pb, Cd, and\\/ inexpensive chemicals are used to reduce contaminant solubility in contaminated soil, has gained attention. We investigated the effective- or Zn in contaminated soil). Organic amendments used ness of lime-stabilized biosolid (LSB), N-Viro Soil (NV), rock phos- to immobilize Pb, Cd, and Zn in

N. T. Basta; R. Gradwohl; K. L. Snethen; J. L. Schroder

2001-01-01

183

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

USGS Publications Warehouse

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.

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

184

In Vitro Screening of Environmental Chemicals for Targeted Testing Prioritization: The ToxCast Project  

PubMed Central

Background Chemical toxicity testing is being transformed by advances in biology and computer modeling, concerns over animal use, and the thousands of environmental chemicals lacking toxicity data. The U.S. Environmental Protection Agency’s ToxCast program aims to address these concerns by screening and prioritizing chemicals for potential human toxicity using in vitro assays and in silico approaches. Objectives This project aims to evaluate the use of in vitro assays for understanding the types of molecular and pathway perturbations caused by environmental chemicals and to build initial prioritization models of in vivo toxicity. Methods We tested 309 mostly pesticide active chemicals in 467 assays across nine technologies, including high-throughput cell-free assays and cell-based assays, in multiple human primary cells and cell lines plus rat primary hepatocytes. Both individual and composite scores for effects on genes and pathways were analyzed. Results Chemicals displayed a broad spectrum of activity at the molecular and pathway levels. We saw many expected interactions, including endocrine and xenobiotic metabolism enzyme activity. Chemicals ranged in promiscuity across pathways, from no activity to affecting dozens of pathways. We found a statistically significant inverse association between the number of pathways perturbed by a chemical at low in vitro concentrations and the lowest in vivo dose at which a chemical causes toxicity. We also found associations between a small set of in vitro assays and rodent liver lesion formation. Conclusions This approach promises to provide meaningful data on the thousands of untested environmental chemicals and to guide targeted testing of environmental contaminants.

Judson, Richard S.; Houck, Keith A.; Kavlock, Robert J.; Knudsen, Thomas B.; Martin, Matthew T.; Mortensen, Holly M.; Reif, David M.; Rotroff, Daniel M.; Shah, Imran; Richard, Ann M.; Dix, David J.

2010-01-01

185

The contaminated land regime in England and Wales and the corporatisation of environmental lawyers  

Microsoft Academic Search

Prior to the introduction of a contaminated land regime in England and Wales, the role of the environmental lawyer was limited and focussed on regulatory compliance issues. Even in a transactional setting, this tended to confine the role to one of environmental due diligence. The regime has allowed the ‘corporatisation’ of environmental lawyers bringing them into the heart of transactions

Robert G. Lee; Steven Vaughan

2010-01-01

186

Assessment and control of environmental contamination from trace elements in coal processing wastes  

Microsoft Academic Search

Environmental problems associated with discarded refuse from coal cleaning and processing are recognized, including waste-bank instability, acid drainage from disposal areas, and noxious emissions from burning wastes. EPA, and other organizations, support efforts to develop methods for controlling forms of environmental contamination. Attention has turned to the environmental hazards posed by the vast array of potentially harmful trace elements in

E. M. Wewerka; J. M. Williams; P. L. Wanek

1976-01-01

187

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

SciTech Connect

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.

Qafoku, Nikolla

2012-01-01

188

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...

189

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

Microsoft Academic Search

This article covers challenges and trends in the determination of some major food chemical contaminants and allergens, which—among\\u000a others—are being monitored by Health Canada’s Food Directorate and for which background levels in food and human exposure\\u000a are being analyzed and calculated. Eleven different contaminants\\/contaminant groups and allergens have been selected for detailed\\u000a discussion in this paper. They occur in foods

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

190

Contaminant degradation in physically and chemically heterogeneous aquifers.  

PubMed

This paper examines the importance of the correlation between hydraulic conductivity (K) and degradation rate constant (k) during the transport of reactive contaminants in heterogeneous aquifers. We simulated reactive transport in an ensemble of two-dimensional heterogeneous aquifers. Two sets of transport simulations were conducted: one in which a perfect positive correlation was assumed between ln(K) and ln(k), and one in which a perfect negative correlation was assumed. We found that the sign of the correlation has important consequences for the contaminant transport. Qualitatively, a negative correlation leads to significantly more pronounced "fingering" of the contaminant plume than does a positive correlation, with potentially important consequences for downgradient receptors. Quantitatively, the expected behavior (as quantified by the contaminant mass remaining in the aquifer) is statistically different between the positive and negative cases: on average, more contaminant mass persists when K and k are negatively correlated. Also, the negative correlation leads to more variability between realizations of the ensemble, whereas a positive correlation induces relatively little variability between realizations. We discuss the implications of these findings for the management of contaminated aquifers. PMID:17854951

Cunningham, Jeffrey A; Fadel, Ziad J

2007-08-02

191

Issue Framing and Citizen Apathy Toward Local Environmental Contamination  

Microsoft Academic Search

We adapt the frame-alignment perspective in order to demonstrate how institutional framing shapes media coverage of a toxic crisis. This framing activity is described as a new approach to managing public responses to contamination that differs from the approach characterizing contamination episodes at Love Canal and Woburn, MA. Our analysis focuses on the process by which actors responsible for managing

Stephen Zavestoski; Kate Agnello; Frank Mignano; Francine Darroch

2004-01-01

192

Results for the Second Quarter 2010 Tank 50 WAC Slurry Sample: Chemical and Radianuclide Contaminant Results.  

National Technical Information Service (NTIS)

This report details the chemical and radionuclide contaminant results for the characterization of the 2010 Second Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC).1 Information from this characterization will be used by Liquid...

M. Reigel N. Bibler

2010-01-01

193

Results for the First Quarter 2010 Tank 50 WAC Slurry Sample: Chemical and Radionuclide Contaminant Results.  

National Technical Information Service (NTIS)

This report details the chemical and radionuclide contaminant results for the characterization of the 2010 First Quarter sampling of Tank 50 for the Saltstone Waste Acceptance Criteria (WAC). Information from this characterization will be used by Liquid W...

M. Reigel N. Bibler

2010-01-01

194

Safety Considerations for Renovation and Demolition of Facilities Contaminated with Chemical Agents.  

National Technical Information Service (NTIS)

The principle objective of a safety program for renovation and demolition operations with facilities contaminated with chemical agent is to insure safety, consistent with mission requirements, is incorporated into the operations. All hazards that may be e...

T. S. Kartachak G. E. Collins

1984-01-01

195

In Situ Chemical Oxidation for Remediation of Contaminated Groundwater. Frequently Asked Questions.  

National Technical Information Service (NTIS)

This document contains a set of frequently asked questions (FAQ) along with short answers concerning the application of in situ chemical oxidation (ISCO) for remediation of contaminated groundwater. This FAQ guide is designed to provide an overview of the...

M. Crimi

2010-01-01

196

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...

197

Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part I. Acute Toxicity of Five Chemicals  

Microsoft Academic Search

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

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

2005-01-01

198

SEDIMENT 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 sediment contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to determine the concentrations of contaminants and toxicities...

199

Indoor air quality for chemical and ultrafine particle contaminants from printers  

Microsoft Academic Search

There are various emission sources of chemical contaminants, such as volatile organic compounds (VOCs) and ozone and particulate matter. This report is a study into the indoor air of a room containing either a laser printer\\/ink-jet printer, and the air contaminations were monitored for VOCs, ozone and ultrafine particle. The result confirmed an increase in the concentration of ozone and

Naoki Kagi; Shuji Fujii; Youhei Horiba; Norikazu Namiki; Yoshio Ohtani; Hitoshi Emi; Hajime Tamura; Yong Shik Kim

2007-01-01

200

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

PubMed

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

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

2013-08-12

201

Toxicology studies of a chemical mixture of 25 groundwater contaminants: Hepatic and renal assessment, response to carbon tetrachloride challenge, and influence of treatment?induced water restriction  

Microsoft Academic Search

Because groundwater contamination is an important environmental concern, we examined the hepatic and renal effects of repeated exposure to a mixture of 25 chemicals frequently found in groundwater near hazardous?waste disposal sites and the effect of such exposure on carbon tetrachloride (CCI4) toxicity. Adult male F?344 rats received ad libitum deionized water and feed (Ad Lib Water) or ad libitum

Jane Ellen Simmons; Raymond S. H. Yang; David J. Svendsgaard; Morrow B. Thompson; John C. Seely; Anthony McDonald

1994-01-01

202

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

NASA Astrophysics Data System (ADS)

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.

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

2011-04-01

203

Pulmonary toxicity and environmental contamination: radicals, electron transfer, and protection by antioxidants.  

PubMed

The atmosphere is replete with a mixture of toxic substances, both natural and man-made. Inhalation of toxic substances produces a variety of insults to the pulmonary system. Lung poisons include industrial materials, particulates from mining and combustion, agricultural chemicals, cigarette smoke, ozone, and nitrogen oxides, among a large number of other chemicals and environmental contaminants. Many proposals have been advanced to explain the mode of action of pulmonary toxicants. In this review we focus on mechanisms of pulmonary toxicity that involve ET, ROS, and OS. The vast majority of toxicants or their metabolites possess chemical ET functionalities that can undergo redox cycling. Such recycling may generate ROS that can injure various cellular constituents in the lung and in other tissues. ET agents include quinones, metal complexes, aromatic nitro compounds, and conjugated iminium ions. Often, these agents are formed metabolically from parent toxicants. Such metabolic reactions are often catalytic and require only small amounts of the offending material. Oxidative attack is commonly associated with lipid peroxidation and oxidation of DNA, and it may result in strand cleavage and 8-OH-DG production. Toxicity is often accompanied by depletion of natural AOs, which further exacerbates the toxic effect. It is not surprising that the use of AOs, both natural in fruits and vegetables, as well as synthetic, may provide protection from the adverse effects of toxicant exposure. The mechanistic framework described earlier is also applicable to some of the more prominent pulmonary illnesses, such as asthma, COPD, and cancer. PMID:19484588

Kovacic, Peter; Somanathan, Ratnasamy

2009-01-01

204

Isotope Biomonitoring in Riverine Ecosystems: Tools for Understanding Linkages Between Environmental Contaminants and Basin Characteristics  

Microsoft Academic Search

Concentrations of accumulative environmental contaminants (e.g., metals and organocholoro-pesticides) often exhibit wide temporal variations in riverine systems. Aquatic fauna, however, concentrate these contaminants into their biomass, providing a relatively long-term integrated record of water quality. In order to accurately determine how these contaminants are bioaccumulated within local food webs, it is essential to understand the relative trophic positions of the

C. Kendall; S. D. Wankel; G. Cabana; C. Schmitt

2002-01-01

205

Environmental Whole-Genome Amplification to Access Microbial Diversity in Contaminated Sediments  

Microsoft Academic Search

Low-biomass samples from nitrate and heavy metal contaminated soils yield DNA amounts that have limited use for direct, native analysis and screening. Multiple displacement amplification (MDA) using ?29 DNA polymerase was used to amplify whole genomes from environmental, contaminated, subsurface sediments. By first amplifying the genomic DNA (gDNA), biodiversity analysis and gDNA library construction of microbes found in contaminated soils

C. B. Abulencia; D. L. Wyborski; J. Garcia; M. Podar; W. Chen; S. H. Chang; H. W. Chang; D. Watson; E. I. Brodie; T. C. Hazen; M. Keller

2005-01-01

206

Characterization of Chemical Waste Site Contamination and Determination of Its Extent Using Bioassays.  

National Technical Information Service (NTIS)

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 site...

J. M. Thomas J. R. Skalski J. F. Cline M. C. McShane W. E. Miller

1986-01-01

207

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 ...

208

FINAL REPORT. ENVIRONMENTAL ANALYSIS OF ENDOCRINE DISRUPTING EFFECTS FROM HYDROCARBON CONTAMINANTS IN THE ECOSYSTEM  

EPA Science Inventory

The objective of this project was to determine how environmental contaminants, namely hydrocarbons, act as hormones or anti- hormones in different species present in aquatic ecosystems. The three major components of the research included: 1)a biotechnology based screening system ...

209

Improved Radiation Dosimetry/Risk Estimates to facilitate Environmental Management of Plutonium contaminated Sites  

SciTech Connect

The main objective of this research is to evaluate health-risk distributions for plutonium (Pu) inhalation-exposure scenarios relevant to environmental management of plutonium dioxide (PuO2)-contaminated sites. These distributions incorporate variability/uncertainty.

Scott, Bobby R.; Hoover, Mark D.; Cheng, Yung-Sung; Schollnberger, Helmut

2000-06-01

210

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...

211

Waste reduction by separation of contaminated soils during environmental restoration  

SciTech Connect

During cleanup of contaminated sites, Sandia National Laboratories, New Mexico (SNL/NM) frequently encounters soils with low-level radioactive contamination. The contamination is not uniformly distributed, but occurs within areas of clean soil. Because it is difficult to characterize heterogeneously contaminated soils in detail and to excavate such soils precisely using heavy equipment, it is common for large quantities of uncontaminated soil to be removed during excavation of contaminated sites. This practice results in the commingling and disposal of clean and contaminated material as low-level waste (LLW), or possibly low-level mixed waste (LLMW). Until recently, volume reduction of radioactively contaminated soil depended on manual screening and analysis of samples, which is a costly and impractical approach and does not uphold As Low As Reasonably Achievable (ALARA) principles. To reduce the amount of LLW and LLMW generated during the excavation process, SNL/NM is evaluating two alternative technologies. The first of these, the Segmented Gate System (SGS), is an automated system that located and removes gamma-ray emitting radionuclides from a host matrix (soil, sand, dry sludge). The matrix materials is transported by a conveyor to an analyzer/separation system, which segregates the clean and contaminated material based on radionuclide activity level. The SGS was used to process radioactively contaminated soil from the excavation of the Radioactive Waste Landfill. The second technology, Large Area Gamma Spectroscopy (LAGS), utilizes a gamma spec analyzer suspended over a slab upon which soil is spread out to a uniform depth. A counting period of approximately 30 minutes is used to obtain a full-spectrum analysis for the isotopes of interest. The LAGS is being tested on the soil that is being excavated from the Classified Waste Landfill.

Roybal, J.A.; Conway, R.; Galloway, B.; Vinsant, E. [Sandia National Labs., Albuquerque, NM (United States); Slavin, P. [GRAM, Inc., Albuquerque, NM (United States); Guerin, D. [Technadyne Engineering Consultants, Inc., Albuquerque, NM (United States)

1998-06-01

212

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...

213

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 ...

214

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...

215

Catchment-scale environmental controls of sediment-associated contaminant dispersal  

Microsoft Academic Search

Globally river sediment associated contaminants, most notably heavy metals, radionuclides, Polychlorinated Biphenyls (PCBs), Organochlorine pesticides (OCs) and phosphorous, constitute one the most significant long-term risks to ecosystems and human health. These can impact both urban and rural areas and, because of their prolonged environmental residence times, are major sources of secondary pollution if contaminated soil and sediment are disturbed by

Mark Macklin

2010-01-01

216

Bioremediation of petroleum-contaminated soils: The environmental restoration of a former railyard  

Microsoft Academic Search

Petroleum contamination is a pervasive environmental problem. The common remedial solution has been to excavate and landfill the contaminated soils, which is hampered by high costs and space limitations at traditional disposal facilities. Bioremediation is a more attractive soil remediation alternative. This method is winning favor primarily because the soil can be treated on site, and the bioremediation systems can

D. S. Jackson; P. Scovazzo

1993-01-01

217

Putative mechanisms of environmental chemical-induced steatosis.  

PubMed

Liver disease is a major health issue characterized by several pathological changes, with steatosis (fatty liver) representing a common initial step in its pathogenesis. Steatosis is of critical importance because prevention of fatty liver can obviate downstream pathologies of liver disease (eg, fibrosis). Recent studies have shown a strong correlation between chemical exposure and steatosis. The work described here identifies chemicals on the US Environmental Protection Agency's Integrated Risk Information System (IRIS) that induce steatosis and investigates putative mechanisms by which these chemicals may contribute to this pathological condition. Mitochondrial impairment, insulin resistance, impaired hepatic lipid secretion, and enhanced cytokine production were identified as potential mechanisms that could contribute to steatosis. Taken together, this work is significant because it identifies multiple mechanisms by which environmental chemicals may cause fatty liver and expands our knowledge of the possible role of environmental chemical exposure in the induction and progression of liver disease. PMID:23197488

Kaiser, J Phillip; Lipscomb, John C; Wesselkamper, Scott C

2012-11-29

218

Chemical and bioassay monitoring of PCB-contaminated soil remediation using solvent extraction technology.  

PubMed

Illegal dumping of polychlorinated biphenyl (PCB) capacitors was discovered in Kobe, Japan, in 2001, leaving about 68 m(3) (92 tons) of soil contaminated with approximately 6.6 kg of PCBs. Solvent extraction technology carried out in 2002-2003 using isopropyl alcohol remedied the affected soil at the site. Forty-seven batch treatments were conducted during full-scale treatment. On average, 8.4 extraction cycles per batch were needed to achieve the clean-up goal for PCBs (i.e., the Japanese environmental quality standard for soil). Analytical results showed that the average PCB concentration (88 microg g(-1)-dry soil) in untreated soil samples of all the batches was decreased to 1.2 microg g(-1)-dry soil in treated soil samples, yielding a removal efficiency of 98.6%. Dioxin responsive-chemical activated luciferase gene expression assay (DR-CALUX) and enzyme-linked immunosorbent assay (ELISA) adopting a monoclonal antibody against 2,3',4,4',5-pentachlorobiphenyl (PCB #118) were used to rapidly screen soil samples before and after solvent extraction. The DR-CALUX and ELISA results were in good agreement with World Health Organization toxicity equivalent values and analytically determined PCB concentrations, respectively. Regular monitoring during the treatment period confirmed that the applied technology met Japanese environmental and control regulations concerning treatment and disposal of contaminated soils and treatment residues. After full-scale treatment, the amount of PCBs recovered from the solvent purification system approximated the estimated amount of PCBs spilled. PMID:18246213

Takigami, Hidetaka; Etoh, Toru; Nishio, Tsukasa; Sakai, Shin-ichi

2007-12-18

219

Contamination from electrically conductive silicone tubing during aerosol chemical analysis  

SciTech Connect

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.

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

2009-06-01

220

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

SciTech Connect

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.

Not Available

1992-03-01

221

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

SciTech Connect

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.

Not Available

1991-10-01

222

Contaminant modeling. Environmental effects of dredging. Technical note  

SciTech Connect

This note provides initial information on contaminant models that are potentially applicable to situations where the presence of toxic materials in sediments complicates Corps of Engineers (CE) dredging activities.

Bird, S.L.; Dortch, M.

1988-03-01

223

Aquatic insects as environmental monitors of trace metal contamination: Red River, New Mexico  

Microsoft Academic Search

Discontinuous sampling of water for toxic chemicals is unreliable in lotic ecosystems or in systems subjected to sporadic discharges. Such sampling either fails to detect the contaminants or seriously underestimates their concentrations. This study explored the use of resident aquatic insects as biomonitors of trace metal contamination in a river subjected to episodic spills of Mo mill tailings. Aquatic insects

T. R. Lynch; C. J. Popp; G. Z. Jacobi

1988-01-01

224

Amendments for the in situ remediation of contaminated sediments: Evaluation of potential environmental impacts  

Microsoft Academic Search

Active sediment caps represent a comparatively new technology for remediating contaminated sediments. They are made by applying chemically active amendments that reduce contaminant mobility and bioavailability to the sediment surface. The objective of this study was to determine if active cap amendments including organoclay, apatite, and biopolymers have the potential to harm benthic organisms. Methods included laboratory bioassays of amendment

Michael H. Paller; Anna S. Knox

2010-01-01

225

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...

226

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

PubMed

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

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

2013-06-29

227

Environmental Conditions Leading to Shellfish Contamination and Related Outbreaks  

Microsoft Academic Search

Human fecal wastes contain a large variety of viruses that can enter the environment through discharge of waste materials\\u000a from infected individuals. Despite the high diversity of viruses that are introduced into the environment by human fecal pollution,\\u000a only a few have been recognized to cause disease in association with consumption of contaminated shellfish. To explain bivalve\\u000a mollusks contamination, several

Haifa Maalouf; Monique Pommepuy; Françoise S. Le Guyader

2010-01-01

228

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...

229

MEETING IN CANADA: 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 co...

230

CRITERIA FOR CHEMICAL SELECTION FOR PROGRAMS ON HUMAN MILK SURVEILLANCE AND RESEARCH FOR ENVIRONMENTAL CHEMICALS  

Microsoft Academic Search

The people of the United States is exposed to a large number of chemicals in their daily lives. In order to prioritize chemicals that should be considered for surveillance of and\\/or research in human milk, criteria were developed at the Technical Workshop on Human Milk Surveillance and Research on Environmental Chemicals in the United States. The criteria include (1) lipid

Cheston M. Berlin Jr; Sam Kacew; Ruth Lawrence; Judy S. LaKind; Robert Campbell

2002-01-01

231

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...

232

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...

233

RESPONSE OF RAINBOW TROUT TRANSCRIPTOME TO MODEL CHEMICAL CONTAMINANTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

We used high-density glass cDNA microarray for studies of genomic response in yolk-sac fry of rainbow trout to sublethal range of model waterborne contaminants (ß'naphthoflavone, cadmium, carbon tetrachloride and pyrene). For development of diagnostic biomarkers, we selected one up-regulated and one...

234

Nanostructured Materials for Environmental Remediation of Organic Contaminants in Water  

Microsoft Academic Search

Nanostructured materials have opened new avenues in various scientific fields and are providing novel opportunities in environmental science. The increased surface area-to-volume ratio of nanoparticles, quantum size effects, and the ability to tune surface properties through molecular modification make nanostructures ideal for many environmental remediation applications. We describe herein the fabrication of metal and semiconductor nanoparticles for environmental remediation applications,

Sherine O. Obare; Gerald J. Meyer

2004-01-01

235

Importance of Chemical Reactivity in Understanding Environmental Hazard  

Microsoft Academic Search

The focus of the 'Chemistry of Hazardous Materials' course offered during the 1995 fall semester is upon 'chemical reactivity' and its relationship to environmental hazard. The Resource Conservation and Recovery Act (RCRA) defines a hazardous substance as that which exhibits the characteristics of chemical reactivity, corrosivity, ignitability, and toxicity. There are other definitions of hazardous materials that use characteristics that

Charles U. Okonkwo

236

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

PubMed Central

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.

Gennings, Chris; Ellis, Rhonda; Ritter, Joe

2011-01-01

237

Prevention of optics and resist contamination in 300-mm lithography: improvements in chemical air filtration  

NASA Astrophysics Data System (ADS)

Atmospheric pressure deep UV lithography using fast chemically amplified photoresists will be the mainstay of semiconductor production into the foreseeable future. Airborne molecular contamination (AMC) in the form of bases and condensable organic and inorganic materials however, threaten both sensitive optics and modern resists thereby creating a host of yield limiting contamination issues. Past work by Kunz at MIT has described photo-induced organic contamination of lithographic optics as a significant concern in leading-edge lithography. Moreover, Kinkead and Ercken, and Kishkovich and Dean have published work on the impact of base contamination on CD uniformity in modern photoresists. Herein, the authors discuss solutions to control both optics and resist contamination in a single compact filter system for advanced lithography. The results of this work suggest that resist and optics contamination can be controlled as we enter the era of low K1 factor <150nm/300mm-device production.

Kinkead, Devon A.; Grayfer, Anatoly; Kishkovich, Oleg P.

2001-08-01

238

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

ERIC Educational Resources Information 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…

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

239

Chemical and microbiological assessment of pendimethalin-contaminated soil after treatment with Fenton's reagent  

Microsoft Academic Search

This study assessed chemical effects and microbial response after Fenton's treatment of pendimethalin contaminated soils. The efficiency of the rapid chemical transformation of pendimethalin varied from 25% to greater than 90%. The highest efficiency was associated with a soil having comparatively low organic matter and low acid neutralizing capacity. This is consistent with the role of organic matter as a

Christopher M. Miller; Richard L. Valentine; Marc E. Roehl; Pedro J. J. Alvarez

1996-01-01

240

Chemical fractionation of cadmium, copper, nickel, and zinc in contaminated soils  

Microsoft Academic Search

Heavy metals are potentially toxic to human life and the environment. Metal toxicity depends on chemical associations in soils. For this reason, determining the chemical form of a metal in soils is important to evaluate its mobility and bioavailability. Sequential extraction was used to fractionate four heavy metals (Cd, Cu, Ni, and Zn) from nine contaminated soils into six operationally

Lena Q. Ma; Gade N. Rao

1997-01-01

241

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...

242

Environmental contaminants in bald eagles in the Columbia River estuary  

SciTech Connect

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.

Anthony, R.G.; Garrett, M.G. (Oregon State Univ., Corvallis (United States)); Schuler, C.A. (Fish and Wildlife Service, Portland, OR (United States))

1993-01-01

243

Environmentally-Induced Malignancies: An In Vivo Model to Evaluate the Health Impact of Chemicals in Mixed Waste  

SciTech Connect

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.

Maria Pallavicini

2001-05-04

244

Ecotoxicological and environmental problems associated with the former chemical plant in Tarnowskie Gory, Poland.  

PubMed

The environmental problems related to the former chemical plant in Tarnowskie Gory, with respect to the Quaternary and Triassic groundwater as main receptors, are described and the eco-toxicological impact is discussed. The historical use of that site included industrial mining of ores (Ag, Pb, Zn) and use of Ba, B, Sr, Al, Cu during production of pigment. The majority of used and produced substances were toxic or hazardous. The applied technologies resulted in generation of waste which were mostly dumped without any elementary protection principles. Hydrodynamic modelling showed potential hazard to water-intakes. The variations of spatial distributions of selected contaminants within the Triassic carbonate series indicate that the chemical waste dumped in vicinity of the plant are the sources of groundwater contamination of boron. The results of soil and groundwater monitoring at the constructed landfill show significant contamination, mainly due to leaching from dumped waste, but also from infiltration of non-operating underground installations, and spills of toxic substances during the plant operation. The Quaternary aquifers are heavily contaminated due to the leaching out of chemical compounds from dumping sites. This is hazardous to the Triassic reservoirs--the main sources of potable water for the region. The characteristics of the key contaminants (As, B, Ba and Sr) are provided, including their transport, fate and toxicity. The spatial and temporal distribution of contaminants in groundwater is presented, and observed trends of groundwater quality decrease, mainly with respect to the Triassic aquifers, are discussed. The groundwater risk assessment being developed for the Tarnowskie Gory site should consider the present situation, and provide an approach towards evaluation and assessment of the required remediation measures. PMID:15464626

Malina, Grzegorz

2004-12-15

245

Contamination by Persistent Chemical Pesticides in Livestock Production Systems  

Microsoft Academic Search

The impact of persistent organic pesticides represents one of the major environmental problems as reported in several studies\\u000a and reflected in some mandatory actions at the inter-governmental level. In particular, isomers of Hexachlorocyclohexane (HCH),\\u000a like many others Organochlorine Pesticides (OCPs), are of human health and environmental concern due to their persistence\\u000a in the biosphere. In industrialised countries, Lindane (the ?-isomer

Bruno Ronchi; Pier Paolo Danieli

246

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

NASA Astrophysics Data System (ADS)

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.

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

247

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...

248

Groundwater contaminant model of chemical mass loading and discharge in the Great Lakes Basin  

SciTech Connect

With numerous point and non-point groundwater contaminant sources found throughout the Great Lakes Basin, the potential loading and migration of contaminants into the Great Lakes via subsurface pathways represents a serious cause for concern. A regional scale study of contaminant sources and chemical mass loadings with the Greater Toronto area was conducted. This area was chosen because its diverse contaminant sources and range of land use makes it an ideal area to be used as a model for developed areas throughout North America. A 2-D steady state flow model was used to simulate the groundwater flow regime using representative transmissivities and recharge rates. To calibrate the model, simulated heads were compared to over 8,000 static water levels contained in water well records. A reverse particle tracking routine was invoked in the flow model to provide a visual aid in understanding the movement and discharge of contaminants with time. This routine permits particle travel times to be plotted along their groundwater flow paths. In turn, isochrones [lines of equal travel times from surface water discharge points] were constructed for contaminants that range from relatively conservative inorganic ions to chemically retarded organics. The isochrones formed the basis for predicting long-term contaminant loading of selected chemical parameters from point and non-point sources on receiving streams and Lake Ontario.

Livingstone, S.; Howard, K.W.F. (Univ. of Toronto, Scarborough, Ontario (Canada). Groundwater Research Group)

1992-01-01

249

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

PubMed

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

Javadi, A A; Al-Najjar, M M

2007-01-09

250

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

USGS Publications Warehouse

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.

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

251

Water and Sediment Data for Chemical Indicators of Contamination.  

National Technical Information Service (NTIS)

INTRODUCTION: This subtask of the Interagency Performance Evaluation Team (IPET) Task 9 project focuses on data mining and compilation for chemical results in four Louisiana parishes affected by flooding from Hurricanes Katrina and Rita Orleans, Plaquemin...

A. Bednar S. Larson T. Bowley

2006-01-01

252

Multiple classes of environmental chemicals are associated with liver disease: NHANES 2003-2004.  

PubMed

Biomonitoring studies show that humans carry a body burden of multiple classes of contaminants which are not often studied together. Many of these chemicals may be hepatotoxic. We used the 2003-2004 National Health and Nutrition Examination Survey to evaluate the relationship between alanine aminotransferase (ALT) and 37 environmental contaminants, comprising heavy metals, non-dioxin-like polychlorinated biphenyls (PCBs), and dioxin-like compounds, using a novel method. Linear regression models were constructed for each chemical separately, then as a class, using quartiles to represent exposure and adjusting for age, sex, race, income, and BMI. We then used an optimization approach to compile a weighted sum of the quartile scores, both within and across chemical classes. Using the optimization approach to construct weighted quartile scores, the dioxin like PCB, the non-dioxin like PCB and metal class-level scores were significantly associated with elevated ALT. A significant interaction was detected between the class-level score for metals, and the score for non-dioxin-like PCBs. When including all chemicals in one model, 3 chemicals accounted for 78% of the weight (mercury, PCB 180, 3,3',4,4',5-PNCB) with the remaining 22% associated with 4 chemicals (a dioxin and 3 PCBs). Validation with a holdout dataset indicated that the weighted quartile sum estimator efficiently identifies reproducible significant associations. PMID:23491026

Yorita Christensen, Krista L; Carrico, Caroline K; Sanyal, Arun J; Gennings, Chris

2013-03-09

253

Mercury contamination in the Brazilian Amazon. Environmental and occupational aspects  

Microsoft Academic Search

Mercury (Hg) contamination of miners, riparian and Indian populations and fish in the Amazon region, due to gold extracting activities, has been studied. Samples of hair, urine, and blood of Indians and prospectors, and hair from riparian fish-eating population and fishes from Madeira river, respectively, were collected and analyzed by Cold Vapor, Atomic Absorption Spectrometry (CV-AAS) techniques. The results obtained

A. C. Barbosa; A. A. Boischio; G. A. East; I. Ferrari; A. Gonçalves; P. R. M. Silva; T. M. E. da Cruz

1995-01-01

254

Molecular contamination mitigation in EUVL by environmental control  

Microsoft Academic Search

EUVL tools operate under vacuum conditions to avoid absorption losses. Under these conditions, the MoSi multilayer mirrors are contaminated, resulting in reduced reflection and thus throughput. We report on experiments on MoSi mirrors exposed to EUV radiation from a synchrotron. To mimic the effects of EUV radiation we also exposed samples using an electron gun. The oxidation rate was found

Norbert Koster; Bas Mertens; Rik Jansen; Annemieke van de Runstraat; Frank Stietz; Marco Wedowski; Hans Meiling; Roman Klein; Alexander Gottwald; Frank Scholze; Matthieu Visser; Ralph Kurt; Peer Zalm; Eric Louis; Andrey Yakshin

2002-01-01

255

ENVIRONMENTAL CONTAMINANTS IN BALD EAGLE EGGS FROM THE ALEUTIAN ARCHIPELAGO  

Microsoft Academic Search

N). Concentrations of polychlorinated biphenyls (PCBs), p,p-dichlorodiphenyldichloroethylene (DDE), and Hg in bald eagle eggs were elevated throughout the archi- pelago, 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

Robert G. Anthony; A. Keith Miles; Mark A. Ricca; James A. Estes

2007-01-01

256

Environmental contaminants in caribou in the Northwest Territories, Canada.  

PubMed

Caribou (Rangifer tarandus) are strict herbivores with a winter diet consisting primarily of lichen. This simple food chain makes caribou a good species for monitoring changes in arctic terrestrial ecosystem contamination. The defined ranges of herds across the Northwest Territories (NWT) also enables examination of spatial trends in contaminant exposure. Caribou were collected from five locations in the first half of a study designed to examine levels of a broad spectrum of organochlorine, heavy metal, and radionuclide contaminants. A wide range of contaminants were detected, with most compounds found at relatively low levels. In general, organochlorine residues were significantly lower in caribou from the mainland Bathurst and Qamanirjuaq (Arviat) and the Southampton Island herds than in caribou from Cape Dorset and Lake Harbour on southern Baffin Island. Moderate levels of hexachlorobenzene (HCB) and alpha-hexachlorocyclohexane (alpha-HCH) were detected at all five study sites. HCB residues ranged from a lipid corrected mean of 32.83 ng/g in fat of Bathurst caribou to 129.41 ng/g in Lake Harbour animals. Alpha-HCH levels ranged from 8.11 ng/g in Bathurst animals to 37.9 ng/g in Cape Dorset caribou. Total polychlorinated biphenyl (sigma PCB) residues ranged from 6.24 ng/g in fat of Arviat caribou to 31.68 ng/g in Cape Dorset animals. Congeners 153 and 138 were the most dominant of the 43 congeners tested. Metal levels were also relatively low with the exception of cadmium, which had community means of 9.68- 33.87 micrograms/g in kidney tissue and 1.96-4.39 micrograms/g in liver tissue. Moderate levels of cesium-137 were detected, with community means of 33.2-184.1 Bq/kg in muscle tissue. Long-range atmospheric transport appears to be the primary source of the contaminants detected in this study. PMID:7892575

Elkin, B T; Bethke, R W

1995-01-15

257

Experimental studies on environmental contamination with infected blood during haemodialysis.  

PubMed Central

To assess the relative importance of different postulated modes of spread of hepatitis B in dialysis units, blood charged with various tracer organisms was used in simulated haemodialysis runs in four laboratories, and the resulting contamination of equipment and environment was measured semi-quantitatively. Some airborne spread of the tracer organism occurred when tubing containing contaminated blood was needled as the "patient" went on and came off the dialyser. Virtually no small airborne particles could be demonstrated however in simulated emergencies in which a blood line was disconnected, or even when bottles of blood were dropped on to a hard floor from a height of 2 metres. Bacillus globigii spores from contaminated blood leaked in small numbers into the dialysing fluid through apparently intact coils. T3 phage, with a particle size of the same order as hepatitis B virus, passed in small quantities through the membrane of a Kiil dialyser from blood to dialysing fluid and also in the reverse direction when added to the header tank. A number of other dialysers were also permeable to phage. Visual assessment of the appropriate moment for inserting the venous line into the "patient" at the onset of dialysis was shown to be unreliable, as the displaced fluid from the end of the venous line was already contaminated before it contained visible red blood cells. Considerable contamination of exposed surfaces and of the buttons on the proportionating unit cabinet occurred. Minor visible splashing of blood was a common-place of the laboratory experiments and was shown to be also a common event during routine haemodialysis in two of the dialysis units taking part in the studies.

1975-01-01

258

Environmental and safety obligations of the Chemical Weapons Convention  

SciTech Connect

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.

Tanzman, E.A.

1994-04-07

259

Environmental Measurement While Drilling System for Real-Time Field Screening of Contaminants  

Microsoft Academic Search

Sampling during environmental drilling is essential to fully characterize the spatial distribution and migration of subsurface contaminants. However, analysis of the samples is expensive and time-consuming: off-site laboratory analysis can take weeks or months. Real-time information on environmental conditions, drill bit location and temperature during drilling is valuable in many environmental restoration operations. This type of information can be used

G. J. Lockwood; R. A. Normann; C. V. Williams

1999-01-01

260

Glutathione-S-transferase activity of Fucus spp. as a biomarker of environmental contamination.  

PubMed

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

Cairrão, E; Couderchet, M; Soares, A M V M; Guilhermino, L

2004-12-20

261

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...

262

Chemicals of emerging concern in the Great Lakes Basin: an analysis of environmental exposures.  

PubMed

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 imple

Klecka, Gary; Persoon, Carolyn; Currie, Rebecca

2010-01-01

263

Potential of zerovalent iron nanoparticles for remediation of environmental organic contaminants in water: a review.  

PubMed

Zerovalent iron (ZVI) has the potential to degrade different organic contaminants. Nanoscale zerovalent iron (NZVI) can reduce the contaminants even more rapidly due to its small size and large specific surface area (SSA), compared to granular ZVI. The main objective of this paper is to assess and compare the potential of NZVI for degradation of different contaminants in water under specific environmental conditions. As a first step, the potential reactive functional groups/bonds associated with different contaminants are identified and possible reaction mechanisms are discussed. Thereafter, the reaction efficiencies of different organic contaminants with NZVI are compared. Mass of ZVI and reaction time required to transform a certain amount of contaminated water are calculated based on literature data. Sources of contaminants in the environment and their environmental occurrences are discussed to understand the potential locations where NZVI could be applied for removal of different contaminants. Overall it is observed that azo-compounds are readily transformed in the presence of NZVI particles. Reaction efficiencies of ZVI for reduction of nitro-organic compounds are also reasonably high. However, halogenated compounds with high molecular weights or complex structures (i.e., iodinated contrast media, DDT, polychlorinated biphenyls, etc.) show lower reaction rates with NZVI compared to the widely studied chlorinated hydrocarbons (i.e., trichloroethylene). PMID:24135090

Raychoudhury, Trishikhi; Scheytt, Traugott

2013-01-01

264

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...

265

Removal of Metals from Contaminated Soils by Mineral Processing Techniques Followed by Chemical Leaching  

Microsoft Academic Search

A contaminated soil was exhaustively sampled at various depthson a rectangular sampling grid of 12 by 15 m (107 samples).Four metal contaminated soil samples were submitted to physicaltreatment methods followed by chemical leaching. The treatmentflowsheet consisted of crushing the 2–10 mm contaminatedfraction, various sieving and use of a wet magnetic separatorprocess for the >63 µm size fraction (SF). Subsequently theWilfley

Guy Mercier; Josée Duchesne; Denis Blackburn

2002-01-01

266

Uptake and depuration of organic contaminants by blue mussels ( Mytilus edulis ) exposed to environmentally contaminated sediment  

Microsoft Academic Search

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 polychlorinated biphenyls (PCBs). In addition, concentration factors in the mussels were calculated separately against the dissolved and particulate phase concentrations and the

R. J. Pruell; J. L. Lake; W. R. Davis; J. G. Quinn

1986-01-01

267

Environmental contamination of ready meals by polychlorinated biphenyls (PCBs)  

Microsoft Academic Search

The level of polychlorinated biphenyls (PCBs) contamination in ready meals was investigated to determine exposure compared to other foodstuffs. Chilled ready meals from nine categories (ambient, Chinese, Indian, Traditional UK, Italian, American Tex-Mex, Vegetarian and Organic), and three samples within each category were Soxhlet extracted in triplicate with hexane for 24 h, followed by a clean-up on deactivated silica gel. The

Adeola A. Adenugba; Dena W. McMartin; Angus Beck

2012-01-01

268

Investigation of Selected Potential Environmental Contaminants: Halogenated Benzenes.  

National Technical Information Service (NTIS)

This report reviews the potential environmental hazard from use of the halogenated benzenes. Major focus is in the commercially important chlorinated benzenes, though fluorinated, brominated and iodinated benzenes are also discussed as well as mixed halog...

S. A. Ware W. L. West

1977-01-01

269

Investigation of Selected Potential Environmental Contaminants: Ketonic Solvents.  

National Technical Information Service (NTIS)

This report reviews the potential environmental hazard from the commercial use of ketonic solvents with the exception of acetone. Three ketones - cyclohexanone, methyl ethyl ketone, and methyl isobutyl ketone - dominate the market. Other commercial ketoni...

D. H. Christopher J. Saxena P. H. Howard P. R. Durkin S. S. Lande

1976-01-01

270

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...

271

Investigation of Selected Potential Environmental Contaminants: Butadiene and Its Oligomers.  

National Technical Information Service (NTIS)

The report is a survey and summary of the literature on butadiene and its oligomers. Major aspects of their biological effects, environmental exposure, chemistry, production and use, and regulations are reviewed and assessed. Butadiene is a reactive gas u...

L. M. Miller

1978-01-01

272

Impact on Man of Environmental Contamination Caused by Lead.  

National Technical Information Service (NTIS)

The objectives of the research was to develop and test an interdisciplinary approach to environmental problems using lead as an example, and to evaluate consequences of lead pollution from traffic exhaust and economic and technological effects of steps ta...

H. W. Edwards M. L. Corrin L. O. Grant L. M. Hartman E. R. Reiter

1971-01-01

273

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 ...

274

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...

275

SIMPLE AND EFFECTIVE CHEMICAL DECONTAMINATION OF RADIOACTIVELY CONTAMINATED LEAD  

Microsoft Academic Search

Millions of pounds of lead has been used by the DOE and their contractors as radioactive shielding over the last fifty years. In the process, radioisotopes in different chemical forms have adhered or adsorbed into the surface corrosion matrices, making the lead metal a hazard and expensive to stabilize and bury at approved sites. Physical decontamination methods are generally applicable

Thomas C. Zietlow

276

Chemical concentrations and contamination associated with clandestine methamphetamine laboratories  

Microsoft Academic Search

We conducted a study to determine the chemical exposures associated with the clandestine manufacture of methamphetamine. Two scenarios were utilized, sampling at actual clandestine laboratories as they were being raided by law enforcement (Scenario 1) and sampling at controlled ''cooks'' conducted in houses to be destroyed (Scenario 2). Sampling during Scenario 1 revealed that most suspected laboratories had significant amounts

John W. Martyny; Shawn L. Arbuckle; Charles S. McCammon; Eric J. Esswein; Nicola Erb; Mike Van Dyke

2007-01-01

277

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...

278

Assessment of human exposure to chemical contaminants in foods  

Microsoft Academic Search

One of the most important factors in assessing risk to human health from potentially harmful chemicals in foods is the availability of good data on the exposure of the public to such substances. The means of acquiring these data generally involves monitoring programmes using appropriate sampling procedures and reliable analytical methods for measuring the compounds of concern in a variety

H. B. S. Conacher; J. Mes

1993-01-01

279

Environmental contamination of ready meals by polychlorinated biphenyls (PCBs).  

PubMed

The level of polychlorinated biphenyls (PCBs) contamination in ready meals was investigated to determine exposure compared to other foodstuffs. Chilled ready meals from nine categories (ambient, Chinese, Indian, Traditional UK, Italian, American Tex-Mex, Vegetarian and Organic), and three samples within each category were Soxhlet extracted in triplicate with hexane for 24 h, followed by a clean-up on deactivated silica gel. The cleaned extracts were concentrated to 1 ml under N(2) gas and analyzed on gas chromatography mass spectrometry (GC-MS) for 7 target PCBs (congeners 28, 52, 101, 118, 153, 138, and 180). Individual congener concentrations ranged from non-detectable to 0.40 ng g(-1) (wet weight). The cumulative concentration of all congeners (?PCBs) ranged between 0.20 and 1.00 ng g(-1) (wet weight). These values translate into exposure levels of less than 1 ?g kg(-1)day(-1) for reference men and women of 70 and 57 kg, respectively. This preliminary study demonstrates that ready meals, like many other foods, are contaminated by PCBs and may represent an important route of human exposure given contemporary changes in consumer food choice. Even though low levels of contamination were observed, long-term exposure for population groups consuming a high volume of ready meals may have cause for concern regarding chronic health risks. PMID:22934994

Adenugba, Adeola A; McMartin, Dena W; Beck, Angus

2012-01-01

280

Decontamination of multiple casualties who are chemically contaminated: a challenge for acute hospitals.  

PubMed

Patients who have been contaminated by chemical compounds present a number of difficulties to emergency departments, in particular, the risk of secondary contamination of healthcare staff and facilities. The Department of Health in the United Kingdom has provided equipment to decontaminate chemically contaminated casualties who present at emergency departments. The capacity of this equipment is limited, and although both the ambulance and fire services have equipment to cope with mass casualties at the scene of a chemical incident, there is still the possibility that acute hospitals will be overwhelmed by large numbers of self-presenting patients. The risks and potential consequences of this gap in resilience are discussed and a number of possible practical solutions are proposed. PMID:18557298

Clarke, Simon F J; Chilcott, Rob P; Wilson, James C; Kamanyire, Robie; Baker, David J; Hallett, Anthony

281

Environmental neurotoxicity of chemicals and radiation  

SciTech Connect

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.

Verity, M.A. (Univ. of California, Los Angeles (United States))

1993-06-01

282

Physical and Chemical Environmental Abstraction Model  

SciTech Connect

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.

E. Nowak

2000-11-09

283

[The radioecological problems of Eurasia and the sources of radioactive environmental contamination in the former USSR].  

PubMed

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

Polikarpov, G G; Aarkrog, A

284

Environmental legislation and contamination: the gap between theory and reality in South Africa.  

PubMed

Like many areas of its constitution, South Africa has progressive legislation to both prevent and clean up environmental contamination. However, recent research has highlighted a large gap between legislation and practice. This paper presents the context of the intent of environmental waste legislation in South Africa and highlights a case of mercury contamination in a rural area which illustrates the gap between the theory of legislation and the reality on the ground. Mercury contamination in humans poses well known health threats, yet despite attention from the media, non-governmental organisations and academic researchers, a major pollutant remains and contamination levels remain high, two decades after the original polluting incident took place. PMID:20663602

Papu-Zamxaka, Vathiswa; Harpham, Trudy; Mathee, Angela

2010-11-01

285

In Situ Chemical Oxidation of Contaminated Ground Water: Permanganate Reactive Barrier Systems for the Long-Term Treatment of Contaminants  

SciTech Connect

Oxidation of chlorinated solvents by permanganate has proven to be effective in destroying these compounds in the aqueous phase. A semi-passive, well-based permanganate reactive barrier system (PRBS) was designed in order for the long-term treatment of dissolved contaminant in the ground water. Results from laboratory experiments indicate the PRBS could deliver permanganate at a stable, constant and controllable rate. In this paper, different field designs of the PRBS are discussed. Numerical simulation was conducted to elucidate the parameters that will influence the field implementation of a PRBS. We investigated issues such as permanganate consumption by aquifer materials, variable density flow effect, as well as lateral spreading under different geological settings. Results from this study continue to point to the promise of an in situ chemical oxidation scheme. PRBS provides a potential treatment of the contaminated ground water at relatively low management cost as compared with other alternatives.

Li, X. David; Schwartz, Frank W.

2004-03-31

286

Structural elucidation of organic contaminants by chemical ionisation mass spectrometry  

NASA Astrophysics Data System (ADS)

The PI-CI mass spectra formation for a new family of aromatic amines, with general formula: R1-Ph-NH-Ph-R2 is discussed in correlation with the R1 and R2 structure. The compounds where isolated from some environmental samples by GC/MS technique. The characteristic ions are produced by rearrangement processes involving olefin and alkane neutral molecule elimination from [M+H]+ and sole olefin molecule elimination from [M+ C2H5]+.

Moldovan, Zaharie

2009-08-01

287

Chemicals and environmentally caused diseases in developing countries  

SciTech Connect

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.

Jamall, I.S.; Davis, B. (University of California, Davis, School of Medicine (USA))

1991-06-01

288

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...

289

Guidance manual for health risk assessment of chemically contaminated seafood. Final report  

SciTech Connect

The report was written to assist in the evaluation and interpretation of the human health risks associated with chemical contaminate levels in seafood. High concentrations of toxic chemicals have been found in sediments and marine organisms in parts of Puget Sound. Since heavy consumption of contaminated seafood may pose a substantial human health risk, it's important that assessments of the risk associated with seafood consumption be conducted in a consistent, acceptable manner. The report provides an overview of risk assessment, and describes hazard identification, dose-response assessment, exposure assessment and risk characterization. Guidance is provided on presentation and interpretation of results.

Pastorok, R.A.

1986-06-01

290

Chemodynamics: transport and behavior of chemicals in the environment--a problem in environmental health.  

PubMed Central

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.

Freed, V H; Chiou, C T; Haque, R

1977-01-01

291

A Look At Endocrine Disruptors: Assessing the threat of hormone-disrupting environmental contaminants to birds  

NSDL National Science Digital Library

Volume 2, Number 1 (January 2001) of the Ornithological Council's newsletter BIRDNET includes this issue brief on the influence of hormone-disrupting environmental contaminants on birds. The issue brief covers the basics of endocrine disruptors, policy issues, a review of the state of our knowledge about endocrine disruptors and birds, and suggested research topics that would be useful in better determining the effects of these contaminants on wild birds.

292

Standard reference materials (SRMs) for determination of organic contaminants in environmental samples.  

PubMed

For the past 25 years the National Institute of Standards and Technology (NIST) has developed certified reference materials (CRMs), known as standard reference materials (SRMs), for determination of organic contaminants in environmental matrices. Assignment of certified concentrations has usually been based on combining results from two or more independent analytical methods. The first-generation environmental-matrix SRMs were issued with certified concentrations for a limited number (5 to 10) of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Improvements in the analytical certification approach significantly expanded the number and classes of contaminants determined. Environmental-matrix SRMs currently available include air and diesel particulate matter, coal tar, marine and river sediment, mussel tissue, fish oil and tissue, and human serum, with concentrations typically assigned for 50 to 90 organic contaminants, for example PAHs, nitro-substituted PAHs, PCBs, chlorinated pesticides, and polybrominated diphenyl ethers (PBDEs). PMID:17047949

Wise, Stephen A; Poster, Dianne L; Kucklick, John R; Keller, Jennifer M; Vanderpol, Stacy S; Sander, Lane C; Schantz, Michele M

2006-09-19

293

Environmental contaminants and the reproductive success of lake trout in the Great Lakes: An epidemiological approach  

SciTech Connect

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.

Mac, M.J.; Edsall, C.C. (U.S. Fish and Wildlife Service, National Fisheries Research Center-Great Lakes, Ann Arbor, MI (USA))

1991-08-01

294

Chemical coagulation-based processes for trace organic contaminant removal: current state and future potential.  

PubMed

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

Alexander, Jonathan T; Hai, Faisal I; Al-Aboud, Turki M

2012-08-23

295

Identification of sentinel health events as indicators of environmental contamination.  

PubMed Central

The consensus process was applied to addressing a public health topic; this was a novel endeavor. The following question was addressed: What role, if any, should sentinel health events play in the decision-making process for identifying the effects of environmental exposure? The panel developed three levels of sentinel health events lists: those that are clearly identifiable, those that are potential signs, and those that are indicators of body burdens. Additionally, the panel developed several salient statements regarding the principles of environmental health surveillance and, especially, recommendations for future research.

Rothwell, C J; Hamilton, C B; Leaverton, P E

1991-01-01

296

CNG acid gas removal process isolates environmental contaminants from crude coal gas  

SciTech Connect

Carbon dioxide, hydrogen sulfide, carbonyl sulfide, and numerous other undersirable contaminants, can be effectively removed from crude coal gas by current acid gas removal (AGR) technology. However, the separation of absorbed acid gases from the AGR absorbent, and the simultaneous or subsequent sharp separation of sulfur-containing compounds and other contaminants from carbon dioxide which is necessary to prevent objectionable environmental emissions, are difficult to achieve with existing AGR technology. The CNG AGR Process described here concentrates absorbed acid gases and other contaminants, and regenerates pure AGR absorbent, by triplepoint crystallization of carbon dioxide.

Auyang, L.; Cook, W.J.; Liv, Y.C.; Siwajek, L.

1984-08-01

297

Geochemistry Of Lead In Contaminated Soils: Effects Of Soil Physico-Chemical Properties  

NASA Astrophysics Data System (ADS)

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

Saminathan, S.; Sarkar, D.; Datta, R.; Andra, S. P.

2006-05-01

298

Effect of low temperature thermal treatment on soils contaminated with pentachlorophenol and environmentally persistent free radicals.  

PubMed

The effect of low temperature thermal treatment on soils from a former Superfund wood-treating site contaminated with pentachlorophenol (PCP) and the environmentally persistent free radical (EPFR), pentachlorophenoxyl, was determined. The pentachlorophenoxyl EPFRs' and the PCP molecules' chemical behavior were simultaneously monitored at temperatures ranging from 25 to 300 °C via electron paramagnetic resonance (EPR) spectroscopy and GC-MS analysis, respectively. Two types of thermal treatment were employed: a closed heating (oxygen-starved condition) where the soil was heated under vacuum and an open heating system (oxygen-rich conditions), where the soil was heated in ambient air. EPR analyses for closed heating indicated the EPFR concentration was 2-12 × 10(18) spins/g of soil, with a g-factor and line width (?Hp-p) of 2.00311-2.00323 and 4.190-5.472 G, respectively. EPR analyses for the open heating soils revealed a slightly broader and weaker radical signal, with a concentration of 1-10 × 10(18) spins/g of soil, g-factor of 2.00327-2.00341, and ?Hp-p of 5.209-6.721 G. This suggested the open heating resulted in the formation of a more oxygen-centered structure of the pentachlorophenoxyl radical or additional, similar radicals. The EPFR concentration peaked at 10 × 10(18) spins/g of soil at 100 °C for open heating and 12 × 10(18) spins/g at 75 °C for closed heating. The half-lives of the EPFRs were 2-24 days at room temperature in ambient air. These results suggest low temperature treatment of soils contaminated with PCP can convert the PCP to potentially more toxic pentachlorophenoxyl EPFRs, which may persist in the environment long enough for human exposure. PMID:22548284

dela Cruz, Albert Leo N; Cook, Robert L; Lomnicki, Slawomir M; Dellinger, Barry

2012-05-11

299

Chemical and statistical studies of contaminants in urban lungs.  

PubMed

Lungs taken at autopsy from 100 urban residents were studied to determine concentrations of 21 trace metals, dust, free silica and hydroxyproline. Medical, occupational and environmental histories were collected so that correlation studies might be done. The potential value of this data as a baseline for further studies of occupationally diseased lung tissue was assessed by evaluating the results of an analysis of variance. The personal histories were used as the criteria for classifying the observations (lung concentrations) into groups for the statistical analysis. PMID:211838

Sweet, D V; Crouse, W E; Crable, J V

1978-07-01

300

Core sediment bacteria drive community response to anthropogenic contamination over multiple environmental gradients.  

PubMed

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

Sun, Melanie Y; Dafforn, Katherine A; Johnston, Emma L; Brown, Mark V

2013-05-06

301

[The surveillance of the aeraulic and hydraulic system reduce environmental Aspergillus contamination in hospital].  

PubMed

The aim of this work was to value the evolution of environmental Aspergillus contamination in hospital with respect to aeraulic system and bathrooms works. An analysis on levels of air and surface Aspergillus contamination were determined in patient's rooms and various common sites in a ward of an hospital in Genoa in 1999. As high contamination levels were found, in summer 1999 a radical disinfection and revision of the aeraulic system was settled. In spite of these interventions some samples maintained an high contamination level, even if from only two rooms, so a further disinfection of bathrooms and surfaces became necessary. A period of sampling was conducted after this last intervention until November 2002. At the beginning of our surveillance 59% positive samples and about 50% of them with high contamination level (>1000 CFU/m3) were found. After the revision of the aeraulic system the reduction of positive samples was significative (14.2%), besides all the positive samples regarded only two rooms. In the last valuation period, after a further disinfection of bathrooms and surfaces of the above mentioned rooms, all the samples taken resulted with a contamination level lower than 10 CFU/m3. This findings underlines the importance of environmental surveillance looking for all the contaminated sources; in particular the aeraulic and hydraulic system as well as the proximity hospital building yard not sufficiently protected. PMID:15049548

Crimi, P; Panesi, S; Saettone, F; Macrina, G; Bertoluzzo, L; Antola, M; Pizzetto, R R

302

Chemical and biological systems for treating waste streams contaminated with high explosives  

SciTech Connect

The removal of high explosives (HIE) from ordnance is being accomplished via washout steamout procedures. Because large volumes of waste water are generated by these processes, safe and efficient methods must be developed for their treatment. Activated carbon can be used to efficiently remove HE from aqueous waste streams, but carbon that is laden with HE constitutes a hazardous solid waste. Although conventional treatment methods (i.e., incineration, open burning) are available, they may not be in compliance with existing or future environmental regulations. New and cost-effective methods are therefore required for the elimination of this solid waste. We are developing and demonstrating coupled chemical and biological systems for the safe and economical treatment of HE-laden activated carbon. We have developed a completely engineered treatment system to accomplish this objective and have been operating a pilot treatment system at the Pantex Plant in Amarillo, TX. In this system, HE- contaminated waste water is treated first by activated-carbon adsorption columns. The HE sorbed to carbon is subsequently recovered via heated solvent elution or by base hydrolysis. The HE- or hydrolysate-laden fluid is then treated using a denitrifying culture of microorganisms, which converts the HE or hydrolysate byproducts to less hazardous endproducts. With these methods, the treated carbon can either be re-used or disposed as a nonhazardous waste. This strategy, which has been shown to be effective for the regeneration of carbon and the degradation of RDX and HMX, will be applicable to other energetic chemicals sorbed to activated carbon.

Knezovich, J.P.; Daniels, J.L. [Lawrence Livermore National Lab., CA (United States); Stenstrom, M.K.; Heilmann, H.M. [Univ. of California, Los Angeles, CA (United States). Dept. of Civil and Environmental Engineering Dept.

1995-11-01

303

The effect of environmental contaminants on testicular function  

Microsoft Academic Search

Male reproductive health has deteriorated considerably in the last few decades. Nutritional, socioeconomic, lifestyle and environmental factors (among others) have been attributed to compromising male reproductive health. In recent years, a large volume of evidence has accumulated that suggests that the trend of decreasing male fertility (in terms of sperm count, quality and other changes in male reproductive health) might

Premendu Prakash Mathur; Shereen Cynthia D'Cruz

2011-01-01

304

Environmental Measurement-While-Drilling System for Real-Time Field Screening of Contaminants  

SciTech Connect

Sampling during environmental drilling is essential to fully characterize the spatial distribution and migration of near surface contaminants. However, analysis of the samples is expensive and time-consuming: off-site laboratory analysis can take weeks or months. An alternative screening technology, Environmental Measurement-While-Drilling (EMWD), could save money and valuable time by quickly distinguishing between contaminated and uncontaminated areas. Real time measurements provided by an EMWD system enable on-the-spot decisions to be made regarding sampling strategies. The system also enhances worker safety and provides the added flexibility of being able to steer a drill bit in or out of hazardous zones.

Bishop, L.B.; Lockwood, G.J.; Normann, R.A.; Selph, M.M.; Williams, C.V.

1999-02-22

305

Use of life cycle assessments to evaluate the environmental footprint of contaminated sediment remediation.  

PubMed

Ecological and human risks often drive the selection of remedial alternatives for contaminated sediments. Traditional human and ecological risk assessment (HERA) includes assessing risk for benthic organisms and aquatic fauna associated with exposure to contaminated sediments before and after remediation as well as risk for human exposure but does not consider the environmental footprint associated with implementing remedial alternatives. Assessment of environmental effects over the whole life cycle (i.e., Life Cycle Assessment, LCA) could complement HERA and help in selecting the most appropriate sediment management alternative. Even though LCA has been developed and applied in multiple environmental management cases, applications to contaminated sediments and marine ecosystems are in general less frequent. This paper implements LCA methodology for the case of the polychlorinated dibenzo-p-dioxins and -furans (PCDD/F)-contaminated Grenland fjord in Norway. LCA was applied to investigate the environmental footprint of different active and passive thin-layer capping alternatives as compared to natural recovery. The results showed that capping was preferable to natural recovery when analysis is limited to effects related to the site contamination. Incorporation of impacts related to the use of resources and energy during the implementation of a thin layer cap increase the environmental footprint by over 1 order of magnitude, making capping inferior to the natural recovery alternative. Use of biomass-derived activated carbon, where carbon dioxide is sequestered during the production process, reduces the overall environmental impact to that of natural recovery. The results from this study show that LCA may be a valuable tool for assessing the environmental footprint of sediment remediation projects and for sustainable sediment management. PMID:21520943

Sparrevik, Magnus; Saloranta, Tuomo; Cornelissen, Gerard; Eek, Espen; Fet, Annik Magerholm; Breedveld, Gijs D; Linkov, Igor

2011-04-26

306

Environmental sentinel biomonitors: integrated response systems for monitoring toxic chemicals  

NASA Astrophysics Data System (ADS)

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.

van der Schalie, William H.; Reuter, Roy; Shedd, Tommy R.; Knechtges, Paul L.

2002-02-01

307

A REVIEW OF APPLICATIONS OF LUMINESCENCE TO MONITORING OF CHEMICAL CONTAMINANTS IN THE ENVIRONMENT  

EPA Science Inventory

The recent analytical literature on the application of luminescence techniques to the measurement of various classes of environmentally significant chemicals has been reviewed. Luminescent spectroscopy based methods are compared to other current techniques. Also, examples of rece...

308

REVIEW OF APPLICATIONS OF LUMINESCENCE TO MONITORING OF CHEMICAL CONTAMINANTS IN THE ENVIRONMENT  

EPA Science Inventory

The recent analytical literature on the application of luminescence techniques to the measurement of various classes of environmentally significant chemicals has been reviewed. uminescent spectroscopy based methods are compared to other current techniques. lso, examples of recent...

309

3D modeling of environments contaminated with chemical, biological, radiological and nuclear (CBRN) agents  

Microsoft Academic Search

CBRN Crime Scene Modeler (C2SM) is a prototype 3D modeling system for first responders investigating environments contaminated with Chemical, Biological, Radiological and Nuclear agents. The prototype operates on board a small robotic platform or a hand-held device. The sensor suite includes stereo and high resolution cameras, a long wave infra red camera, chemical detector, and two gamma detectors (directional and

Piotr Jasiobedzki; Ho-Kong Ng; Michel Bondy; Carl H. McDiarmid

2008-01-01

310

Some scientific judgments in the assessment of the risk of environmental contaminants  

SciTech Connect

The assessment of risk due to environmental contaminants depends, in part, on scientific data. When such data are incomplete, as is usually the case, assumptions based on scientific judgments are made to analyze the consequences. Specifically, when health related data needed to assess the risk posed by environmental contaminants are missing or incomplete, it becomes necessary to make assumptions using scientific judgment to estimate the risk. Different scientists can and do make different assumptions, and the resulting differences in opinion can result in controversy. The present discussion presents a few of the consensus judgments of the Science Advisory Board (SAB) of the U.S. Environmental Protection Agency concerning the health effects and risk for such environmental contaminants as 1,2-dichloroethylene, dichloromethane, para-dichlorobenzene, polychlorinated biphenyls, perchloroethylene, and xylene, as well as the implications of the more likely cancer mechanisms, the exposure routes, and pharmacokinetics to the risk assessment process. In some of these examples, the scientific data have been developed to the extent that specific judgments by groups such as the SAB can result in greater confidence that one is correct in the assessment of risk. Because of the uncertainties in current scientific knowledge for many environmental contaminants, judgments differ and there is no right or wrong opinion.

Cothern, C.R. (Environmental Protection Agency, Washington, DC (USA))

1989-05-01

311

Geochemistry Of Lead In Contaminated Soils: Effects Of Soil PhysicoChemical Properties  

Microsoft Academic Search

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.

S. Saminathan; D. Sarkar; R. Datta; S. P. Andra

2006-01-01

312

Final Contaminant Candidate List 3 Chemicals: Classification of the PCCL to CCL.  

National Technical Information Service (NTIS)

Every five years the United States Environmental Protection Agency (EPA) is required to publish a list of contaminants (1) that are currently unregulated, (2) that are known or anticipated to occur in public water systems, and (3) which may require regula...

2009-01-01

313

Chemical contamination assessment of Gulf of Mexico oysters in response to hurricanes Katrina and Rita.  

PubMed

Hurricane Katrina made landfall on August 29, 2005 and caused widespread devastation along the central Gulf Coast states. Less than a month later Hurricane Rita followed a similar track slightly west of Katrina's. A coordinated multi-agency response followed to collect water, sediment and tissue samples for a variety of chemical, biological and toxicological indicators. The National Oceanic and Atmospheric Administration's National Status and Trends Program (NS&T) participated in this effort by measuring chemical contamination in sediment and oyster tissue as part of the Mussel Watch Program, a long-term monitoring program to assess spatial and temporal trends in a wide range of coastal pollutants. This paper describes results for contaminants measured in oyster tissue collected between September 29 and October 10, 2005 and discusses the results in the context of Mussel Watch and its 20-year record of chemical contamination in the region and the nation. In general, levels of metals in oyster tissue were higher then pre- hurricane levels while organic contaminants were at or near record lows. No contaminant reported here exceeded the FDA action level for food safety. PMID:19051046

Johnson, W E; Kimbrough, K L; Lauenstein, G G; Christensen, J

2008-12-03

314

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

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

Jones, Ross J

2011-05-06

315

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...

316

Environmental Progress and Problems: A Chemical Industry Perspective  

Microsoft Academic Search

At the 79th Annual Meeting of the Air Pollution Control Association, a panel discussion was conducted by top environmental leaders detailing some of the country's pollution control accomplishments and the chemical industry's contribution to them. Attention is focused on how to sort out and slate for action major health risks from pollution versus less important ones. Air and water quality,

Harold J. Corbett

1986-01-01

317

ALTERATIONS IN MACROPHAGE FUNCTIONS BY ENVIRONMENTAL CHEMICALS (JOURNAL VERSION)  

EPA Science Inventory

The theme of the review will be to discuss those environmental assaults that impair alveolar macrophage activities. The paper is not intended to completely review all available data on every chemical tested nor will it provide dose-response data. Instead, it is an attempt to prov...

318

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...

319

Reproductive success, developmental anomalies and environmental contaminants in double-crested cormorants (Phalacrocorax auritus)  

USGS Publications Warehouse

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 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.

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

320

Metal fractionation in soils and assessment of environmental contamination in Vallecamonica, Italy.  

PubMed

Metal contamination was investigated in soils of the Vallecamonica, an area in the northern part of the Brescia province (Italy), where ferroalloy industries were active for a century until 2001. The extent in which emissions from ferroalloy plants affected metal concentration in soils is not known in this area. In this study, the geogenic and/or anthropogenic origin of metals in soils were estimated. A modified Community Bureau of Reference sequential chemical extraction method followed by inductively coupled plasma optical emission spectroscopy (ICP-OES) analyses were employed to evaluate the potential bioavailability of Al, Cd, Mn, Fe, Cr, Zn, and Pb in soils. Principal component analysis (PCA) was used to assess the relationships among metal sources in soil samples from different locations. This approach allowed distinguishing of different loadings and mobility of metals in soils collected in different areas. Results showed high concentrations and readily extractability of Mn in the Vallecamonica soils, which may suggest potential bioavailability for organisms and may create an environmental risk and potential health risk of human exposure. PMID:23338992

Borgese, L; Federici, S; Zacco, A; Gianoncelli, A; Rizzo, L; Smith, D R; Donna, F; Lucchini, R; Depero, L E; Bontempi, E

2013-01-22

321

Development of local knowledge of environmental contamination in Sydney, Nova Scotia: environmental health practice from an environmental justice perspective.  

PubMed

In Sydney, Nova Scotia, from 1901 through 1988 a coke and steel factory operated with no pollution controls, depositing over a million tons of particulate matter and releasing several thousands of tons of coal tar into the estuary. Previously we documented the presence of lead, arsenic and PAHs, in soil above Canadian guidelines, and in house dust in the communities surrounding the site [Lambert, TW, Lane, S. Lead, arsenic, and polycyclic aromatic hydrocarbons in soil and house dust in the communities surrounding the Sydney, Nova Scotia, tar ponds. Environ Health Perspect 2004; 112:35-41.]. In this paper we further the research by documenting and developing community knowledge with a study of resident's observations and experiences of the industrial contamination. We conducted two surveys, a quantitative door-to-door survey and qualitative dust interview, designed to complement each other and bring together the observations and experiences in the different communities to develop the local knowledge. The combined methodology uses techniques from both social and physical science, and was developed with the cooperation of community members. The research supports the proposition that local knowledge adds contextual meaning that complements the physical measurement of environmental contaminants, in order to understand the complex environment in which people live, and the multiple exposure pathways through which they can be affected. Residents in all three communities provided vivid observations and detailed experiences of the industrial pollution in their community and homes. The local knowledge is consistent with our physical data and review of the historical scientific research in Sydney, and supports the inference that the community was adversely impacted by the coke and steel facility. From a justice perspective, the three communities should be equally considered for remediation as part of the 'tar pond remediation policy' rather than the current policy of including only a few streets and houses. PMID:16650884

Lambert, Timothy W; Guyn, Lindsay; Lane, Stephanie E

2006-05-02

322

Treatability of contaminated ground water and aquifer solids at town gas sites, using photolytic ozonation and chemical in-situ reclamation. Final report  

SciTech Connect

The feasbility of cleaning up contaminated ground water and aquifer solids from so-called town gas sites using photolytic ozonation and chemical in situ aquifer reclamation (CISR) techniques was investigated in the laboratory. At the actual site, coal was thermally oxidized to produce methane for municipal distribution. The degradation left a coal tar which, if released into the ground, could contaminate ground water and aquifer solids with a number of organic substances, including aromatic hydrocarbons such as benzene, toluene, xylene (BTX), and polynuclear aromatic hydrocarbons (PAHs) at environmentally significant concentrations. A chemical in situ treatment method using persulfate as a source of free radicals destroyed organic contaminants that were adsorbed to the aquifer solids. PAHs were reduced by 34 percent after 12 days of treatment and by 52 percent after 40 days.

Peyton, G.R.; LeFaivre, M.H.; Smith, M.A.

1990-08-01

323

Biotreatment of groundwater contaminated with MTBE: interaction of common environmental co-contaminants.  

PubMed

Contamination of groundwater with the gasoline additive methyl tert-butyl ether (MTBE) is often accompanied by many aromatic components such as benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene (BTEX). In this study, a laboratory-scale biotrickling filter for groundwater treatment inoculated with a microbial consortium degrading MTBE was studied. Individual or mixtures of BTEX compounds were transiently loaded in combination with MTBE. The results indicated that single BTEX compound or BTEX mixtures inhibited MTBE degradation to varying degrees, but none of them completely repressed the metabolic degradation in the biotrickling filter. Tert-butyl alcohol (TBA), a frequent co-contaminant of MTBE had no inhibitory effect on MTBE degradation. The bacterial consortium was stable and showed promising capabilities to remove TBA, ethylbenzene and toluene, and partially degraded benzene and xylenes without significant lag time. The study suggests that it is feasible to deploy a mixed bacterial consortia to degrade MTBE, BTEX and TBA at the same time. PMID:16733621

Wang, Xiaolin; Deshusses, Marc A

2006-05-30

324

Chemical characterization and toxicological testing of windrow composts from explosives-contaminated sediments  

Microsoft Academic Search

Aerated and nonaerated windrow composts of explosives-contaminated sediments at the Umatilla Army Depot Activity (UMDA, Hermiston, OR) were characterized chemically and toxicologically as a function of composting time. The concentrations of explosives in organic solvent extracts of the composts and in the aqueous leachates of the composts, the bacterial mutagenicity of organic solvent extracts from the composts, and the toxicity

W. H. Griest; R. L. Tyndall; A. J. Stewart; J. E. Caton; A. A. Vass; C.-H. Ho; W. M. Caldwell

1995-01-01

325

Bacterial Biodiversity in Soil with an Emphasis on Chemically-Contaminated Soils  

Microsoft Academic Search

Microorganisms isolated from soil are sources of known and new microorganisms and genetic material. This review examines general principles of soil bacterial biodiversity, limitations in sampling soils, and examples of bacterial diversity in chemically-contaminated soils. Both conventional and molecular methods used to assess microbial biodiversity in soils will be addressed as well as selected examples of the effects of organic

J. T. Trevors

1998-01-01

326

Monitoring chemical contamination levels in the Mediterranean based on the use of mussel caging  

Microsoft Academic Search

Within the framework of the biointegrator network (RINBIO), 92 man-made cages containing mussels (Mytilus galloprovincialis), distributed over 1800 km of the French Mediterranean coast, made it possible to assess chemical contamination by heavy metals (Cd, Hg, Zn, Pb, Cu, Ni, Cr, As) and organic compounds (DDT, PCBs, HAP). The caging technique was adopted to compensate for the scarcity of natural

Bruno Andral; Jean Yves Stanisiere; Didier Sauzade; Elodie Damier; Hervé Thebault; François Galgani; Pierre Boissery

2004-01-01

327

Removal of chemical and microbiological contaminants from domestic greywater using a recycled vertical flow bioreactor (RVFB)  

Microsoft Academic Search

Reuse of domestic greywater (GW) for non-potable purposes is emerging as an important approach to the management and conservation of water resources, particularly in rural and developing areas where small-scale decentralized treatments are suited. Recently, researchers at Ben-Gurion University (Israel) have developed a modular system – the recycled vertical flow bioreactor (RVFB) – for the removal of chemical contaminants from

Amit Gross; Drora Kaplan; Katherine Baker

2007-01-01

328

Chemical modifications of groundwater contaminated by recharge of treated sewage effluent  

Microsoft Academic Search

Long-term monitoring of the chemical composition of recharge sewage effluent and associated contaminated groundwater from the Dan Region Sewage Reclamation Project shows, after 16 years of recharge operation, the presence of a distinct saline plume (up to 400 mg\\/l Cl), extending 1600 m downgradient in the Coastal Plain aquifer of Israel. The recorded electrolyte composition of groundwater in the vicinity

Avner Vengosh; Rami Keren

1996-01-01

329

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...

330

Desorption electrospray ionization mass spectrometry in the analysis of chemical food contaminants in food  

Microsoft Academic Search

Since its introduction, desorption electrospray ionization (DESI) mass spectrometry (MS) has been mainly applied in pharmaceutical and forensic analysis. We expect that DESI will find its way in many different fields, including food analysis. In this review, we summarize DESI developments aimed at controlling chemical contaminants in food. Data are given for analysis of pesticides, natural toxins, veterinary drugs, food

M. W. F. Nielen; H. Hooijerink; P. Zomer; J. G. J. Mol

2011-01-01

331

Health and environmental effects of complex chemical mixtures: proceedings  

SciTech Connect

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.

Not Available

1985-01-01

332

Impact of chemically contaminated sewage sludge on the collard arthropod community  

SciTech Connect

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.

Culliney, T.W.; Pimentel, D.; Lisk, D.J.

1986-08-01

333

Overall multi-media persistence as an indicator of potential for population-level intake of environmental contaminants  

SciTech Connect

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.

MacLeod, Matthew; McKone, Thomas E.

2003-06-01

334

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

Microsoft Academic Search

'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

McLachlan

1998-01-01

335

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

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.

Bertsch, Paul M.; Sowder, Andrew; Jackson, Brian

2003-06-01

336

Nonradiological chemical pathway analysis and identification of chemicals of concern for environmental monitoring at the Hanford Site  

SciTech Connect

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.

Blanton, M.L.; Cooper, A.T.; Castleton, K.J.

1995-11-01

337

Environmental politics and science: the case of PBB contamination in Michigan.  

PubMed Central

This article examines how politics and science interacted against a background of uncertainty to shape policy in the case of environmental contamination by polybrominated biphenyls (PBB) in Michigan. In 1973, between 500 and 1,000 pounds of the flame retardant PBB were accidentally shipped and used instead of the dairy feed additive magnesium oxide, resulting in the widespread contamination of animal feeds, animals, and human food products. The contamination was initially perceived as the private trouble of a single farmer. The problem next became a public issue as public and private institutions grappled with questions of illness, safety, and disposal. To gain influence over those institutions, dissatisfied individuals and groups then turned the PBB contamination into a political controversy. The final section of the present article analyzes how science and politics interacted in: the ways bureaucratic organizations defined the three problems of contamination; the role political controversy played in redefining problems and influencing policy; and the political roles of scientists in controversies over environmental contamination.

Reich, M R

1983-01-01

338

Characterization of chemical-waste-site contamination and determination of its extent using bioassays  

Microsoft Academic Search

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 to their toxic potential or mapped for cleanup operations. The objectives of the study were to (a) assess the

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

1986-01-01

339

Combined use of environmental data and biomarkers in fish (Liza aurata) inhabiting a eutrophic and metal-contaminated coastal system - Gills reflect environmental contamination.  

PubMed

An investigative biomonitoring study was carried out in a eutrophic coastal system with a moderate contamination by metals (Obidos lagoon, Portugal), combining the evaluation of exposure concentrations with metals accumulation and oxidative stress responses in gills of the golden grey mullet (Liza aurata). Two contrasting seasons (winter and summer) were considered at three sites: Barrosa (BB) and Bom-Sucesso (BS) branches; Middle lagoon (ML). Data on the water column pointed to a higher metals and nutrients availability at BB that was reflected in the higher metal concentrations in gills, particularly in winter. Similarly, oxidative stress responses demonstrated a pro-oxidant challenge at BB (winter and summer), which was corroborated by an integrated biomarker response index (IBR). Metal concentrations in gills were higher in summer than winter, reflecting the increased environmental concentrations in combination with elevated metabolic rates. Catalase (CAT), glutathione-S-transferase (GST), total glutathione (GSH(t)) and lipid peroxidation (LPO) increases observed in winter at BB were related with metal accumulation, while summer enhancement of glutathione peroxidase (GPx), glutathione reductase (GR), GST and GSH(t) was associated with other stressors. Inter-site differences on the basis of IBR were more accentuated in winter. Gills can be considered as an important route of entry for contaminants and were demonstrated to reflect water contamination and are therefore useful in the context of environmental assessment. PMID:19783293

Pereira, Patrícia; de Pablo, Hilda; Vale, Carlos; Pacheco, Mário

2009-08-21

340

Health risk implications from simultaneous exposure to multiple environmental contaminants.  

PubMed

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

Genthe, B; Le Roux, W J; Schachtschneider, K; Oberholster, P J; Aneck-Hahn, N H; Chamier, J

2013-05-10

341

Bis-(2-ethylhexyl) phthalate, an ubiquitous environmental contaminant  

SciTech Connect

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.

Griffiths, W.C.; Camara, P.; Lerner, K.S.

1985-03-01

342

Environmental contaminants in tissues, foods, and feces of California condors  

USGS Publications Warehouse

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.

Wiemeyer, S.N.; Krynitsky, A.J.; Wilbur, S.R.

1983-01-01

343

Illicit drugs, a novel group of environmental contaminants.  

PubMed

It is now well established that residues from therapeutic drugs consumed by humans can end up, through the sewage system, in the surface water of populated areas. Given that the global production of major illicit drugs is comparable to that of widely used pharmaceuticals, we tested for the presence of drugs of abuse (cocaine, opioids, amphetamines and cannabis derivatives), some related opioid pharmaceuticals (codeine and methadone) and/or their metabolites in Italian and British surface waters. Having identified residues of all major drugs of abuse in raw and treated urban wastewater, we now measured their levels in several rivers and lakes by a selective multi-residue assay based on liquid chromatography-tandem mass spectrometry. Recoveries in surface water were generally higher than 80%, with overall variability of the method lower than 10%. LODs were generally lower than 0.2 ng/L, and LOQs were lower than 0.6 ng/L, with few exceptions. Many of the tested substances were found in both rivers and lakes, at concentrations ranging from high pg/L to high ng/L, with loads in rivers in the range of tenths to hundreds of grams per day. Our data indicate that residues of drugs of abuse have become widespread surface water contaminants in populated areas. Since most of these residues still have potent pharmacological activities, their presence in the aquatic environment may have potential implications for human health and wildlife. PMID:17935751

Zuccato, Ettore; Castiglioni, Sara; Bagnati, Renzo; Chiabrando, Chiara; Grassi, Paola; Fanelli, Roberto

2007-09-21

344

IDENTIFICATION OF ATTRIBUTES FOR SELECTION OF WATERBORNE ORGANISMS FOR THE ENVIRONMENTAL PROTECTION AGENY'S CONTAMINANT CANDIDATE LIST (CCL)  

EPA Science Inventory

Under the revisions of the Safe Drinking Water Act of 1996 the U. S. Environmental Protection Agency is required to identify contaminants which may have an adverse health effects for inclusion on a Contaminant Candidate List. Contaminants from this list are further reviewed to de...

345

Consumer perceptions of risks of chemical and microbiological contaminants associated with food chains: A cross-national study  

Microsoft Academic Search

The development and implementation of effective systems to identify vulnerabilities in food chains to chemical and microbiological contaminants must take account of consumer priorities and preferences. The present investigation attempted to understand consumer perceptions associated with chemical and microbiological contaminants in four specific food chains (drinking water, farmed salmon, chicken and milk powder). To this end, ten focus group discussions

S. V. Kher; Jonge de J; M. T. A. Wentholt; R. Deliza; J. Cunha de Andrade; H. J. Cnossen; N. B. Lucas Luijckx; L. J. Frewer

2011-01-01

346

Grand challenge problems in environmental modeling and remediation: groundwater contaminant transport  

Microsoft Academic Search

This report describes briefly the work of the Center for Subsurface Modeling (CSM) of the University of Texas at Austin (and Rice University prior to September 1995) on the Partnership in Computational Sciences Consortium (PICS) project entitled Grand Challenge Problems in Environmental Modeling and Remediation: Groundwater Contaminant Transport.

Todd Arbogast; Steve Bryant; Clint N. Dawson; Mary F. Wheeler

1998-01-01

347

Environmental contamination from trace elements in coal preparation wastes: a literature review and assessment  

Microsoft Academic Search

The purpose of this review of the literature is to collect and evaluate the available information on the chemistry and behavior of trace elements in coal processing wastes, and to utilize this information to assess the potential for environmental contamination from the trace elements in these wastes. Only limited attention has been given previously to the chemistry of trace elements

E. M. Wewerka; J. M. Williams; P. L. Wanek; J. D. Olsen

1976-01-01

348

IN VITRO METABOLISM AND DNA ADDUCT FORMATION FROM THE MUTAGENIC ENVIRONMENTAL CONTAMINANT 2-NITROFLURORANTHENE  

EPA Science Inventory

The metabolism and DNA adduct formation by the mutagenic environmental contaminant 2-nitrofluoranthene (2-NFA) was studied. ncubation under aerobic conditions with liver microsomes of rats pretreated with 3-methylcholanthrene yielded 2-NFA tran-7.8-dihydrodiol, 2-NFA tran-9,10-di...

349

ENVIRONMENTAL CONTAMINANTS AND POTENTIAL HUMAN RISK ASSOCIATED WITH SELECTED BOTANICAL DIETARY SUPPLEMENTS  

EPA Science Inventory

Botanical dietary supplements have a long history of use in Europe and China and they are becoming increasingly popular in the United States. However, little data is available regarding environmental contaminants in botanical dietary supplements and the risk posed to those ingest...

350

Environmental contaminants in surrogates, foods, and feathers of California condors ( Gymnogyps californianus )  

Microsoft Academic Search

California condor (Gymnogyps californianus) foods and feathers, and turkey vultures (Cathartes aura), common ravens (Corvus corax), and their eggs were collected within the condor range to determine exposure of condors to environmental contaminants. Samples were analyzed for organochlorines and trace elements. Food items contained low concentrations of organochlorines and generally low concentrations of lead. DDE was detected in all vulture

Stanley N. Wiemeyer; Ronald M. Jurek; John F. Moore

1986-01-01

351

Grand challenge problems in environmental modeling and remediation: groundwater contaminant transport  

SciTech Connect

This report describes briefly the work of the Center for Subsurface Modeling (CSM) of the University of Texas at Austin (and Rice University prior to September 1995) on the Partnership in Computational Sciences Consortium (PICS) project entitled Grand Challenge Problems in Environmental Modeling and Remediation: Groundwater Contaminant Transport.

Todd Arbogast; Steve Bryant; Clint N. Dawson; Mary F. Wheeler

1998-08-31

352

Prenatal Exposure of the Northern Quebec Inuit Infants to Environmental Contaminants.  

ERIC Educational Resources Information Center

|Through their marine-based diet, the Inuit of Nunavik (Quebec) are exposed to neurotoxic environmental contaminants that impact cognitive development. Mercury levels in Nunavik Inuit mothers and newborns were higher than in U.S. and Canadian populations but lower than in previous Arctic samples. Lead, polychlorinated biphenyls, chorinated…

Muckle, Gina; Ayotte, Pierre; Dewailly, Eric; Jacobson, Sandra W.; Jacobson, Joseph L.

2001-01-01

353

Osprey: Worldwide Sentinel Species for Assessing and Monitoring Environmental Contamination in Rivers, Lakes, Reservoirs, and Estuaries  

Microsoft Academic Search

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

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

2009-01-01

354

Sr(sup 89) -- An unnecessary contaminant of concern in SRS environmental samples.  

National Technical Information Service (NTIS)

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 ...

H. P. Holcomb

1993-01-01

355

Testing human hair for drugs of abuse. IV. Environmental cocaine contamination and washing effects  

Microsoft Academic Search

Active cocaine use results in sequestration of parent drug in hair. In addition, hair has unique physicochemical properties that permit absorption of cocaine from the environment. When hair is tested for evidence of cocaine, it is important to consider whether the positive test resulted from active drug use or environmental contamination. In a series of laboratory experiments, it was found

Wen Ling Wang; Edward J. Cone

1995-01-01

356

Human health implications of environmental contaminants in Arctic Canada: A review  

Microsoft Academic Search

The objectives of this paper are to: assess the impact of exposure to current levels of environmental contaminants in the Canadian Arctic on human health; identify the data and knowledge gaps that need to be filled by future human health research and monitoring; examine how these issues have changed since our first assessment [Van Oostdam, J., Gilman, A., Dewailly, É.,

J. Van Oostdam; S. G. Donaldson; M. Feeley; D. Arnold; P. Ayotte; G. Bondy; L. Chan; É. Dewaily; C. M. Furgal; H. Kuhnlein; E. Loring; G. Muckle; E. Myles; O. Receveur; B. Tracy; U. Gill; S. Kalhok

2005-01-01

357

Use of kriging to estimate spatial patterns and inventories of environmental contaminants  

SciTech Connect

Although Kriging was originally devised to deal with ore reserve estimation in the mining industry, in recent years it has been used in several other fields, including several successful applications involving radioactive contaminants in the environment. Kriging assumes that the difference between the data values at two points is a function only of the distance between them. It is suggested that Kriging has use in the evaluation of many different environmental contaminants where the dispersion of that contaminant begins at some point source and then moves through the environment by a mechanism such as wind or water, so that the concentration of the contaminant at any one time over a field of observation is dependent on the distance from the source to the observation points. The theoretical basis of Kriging and the way this technique can be used to obtain estimates of the distribution and inventory of a spatially correlated variable are described.

Simpson, J.C.; Gilbert, R.O.

1981-01-01

358

Hospital ventilation standards and energy conservation: chemical contamination of hospital air. Final report  

SciTech Connect

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.

Rainer, D.; Michaelsen, G.S.

1980-03-01

359

Partition of Environmental Chemicals between Maternal and Fetal Blood and Tissues  

PubMed Central

Passage of environmental chemicals across the placenta has important toxicological consequences, as well as for choosing samples for analysis and for interpreting the results. To obtain systematic data, we collected in 2000 maternal and cord blood, cord tissue, placenta, and milk in connection with births in the Faroe Islands, where exposures to marine contaminants is increased. In 15 sample sets, we measured a total of 87 environmental chemicals, almost all of which were detected both in maternal and fetal tissues. The maternal serum lipid-based concentrations of organohalogen compounds averaged 1.7 times those of cord serum, 2.8 times those of cord tissue and placenta, and 0.7 those of milk. For organohalogen compounds detectable in all matrices, a high degree of correlation between concentrations in maternal serum and the other tissues investigated was generally observed (r2 > 0.5). Greater degree of chlorination resulted in lower transfer from maternal serum into milk. Concentrations of pentachlorbenzene, ?-hexachlorocyclohexane, and several polychlorinated biphenyl congeners with low chlorination were higher in fetal samples and showed poor correlation with maternal levels. Perfluorinated compounds occurred in lower concentrations in cord serum than in maternal serum. Cadmium, lead, mercury, and selenium were all detected in fetal samples, but only mercury showed close correlations among concentrations in different matrices. Although the environmental chemicals examined pass through the placenta and are excreted into milk, partitions between maternal and fetal samples are not uniform.

2010-01-01

360

Identifying populations at risk from environmental contamination from point sources  

PubMed Central

Objectives: To compare methods for defining the population at risk from a point source of air pollution. A major challenge for environmental epidemiology lies in correctly identifying populations at risk from exposure to environmental pollutants. The complexity of today's environment makes it essential that the methods chosen are accurate and sensitive. Methods: Environmental and mathematical methods were used to identify the population potentially exposed to a point source of airborne pollution emanating from a waste incinerator. Soil sampling was undertaken at 83 sites throughout the city and environs. The concentrations of arsenic and copper were measured at each site. Computer software produced smoothed contour plots of the distribution of arsenic and copper in the soil based on the information derived from the sampling sites. The population at risk was also identified using concentric rings of varying radii, with the source of pollution at the centre. Lastly, we used the sites that had previously been selected and measured the frequency of wind direction, speed and distance from the source of pollution at each site. Theoretical contour plots were constructed using the distance from the source of pollution at each site, with and without incorporating wind frequency as a function of direction. Results: Each method identified different populations at risk from airborne pollution. The use of circles was a very imprecise way of identifying exposed populations. Mathematical modelling that incorporated wind direction was better. Soil sampling at many sites was accurate, as the method is direct; but it is very costly and the close proximity of high and low concentrations hindered interpretation. The smoothed contour plots derived from the soil sampling sites identified an exposed population that was similar to that derived from the spot sampling. Conclusions: Using circles as the only means of identifying the exposed population leads to dilution of the potential health effect. The best approach is to use local knowledge about wind direction and speed to estimate the population likely to be at risk; to back up this estimate by judicious use of soil sampling; to use contour mapping to guide the final selection of exposed and non-exposed populations; and finally, to interpret the populations identified as being at risk by incorporating information about other potential sources of pollution (past and present) in the area.

Williams, F; Ogston, S

2002-01-01

361

Recent Environmental Change and Atmospheric Contamination on Svalbard as Recorded in Lake Sediments – Synthesis and General Conclusions  

Microsoft Academic Search

The major patterns of biostratigraphical and geochemical change detected in a multidisciplinary study on recent environmental change and atmospheric contamination on Svalbard are summarised and synthesised. The patterns discussed are changes in sediment accumulation rates, organic matter accumulation rates, atmospheric contaminants, and biological assemblages (diatoms, chrysophyte cysts, chironomids). Possible environmental factors that may have influenced these patterns are discussed, in

H. J. B. Birks; Vivienne J. Jones; N. L. Rose

2004-01-01

362

Environmental contamination during tracheal suction. A comparison of disposable conventional catheters with a multiple-use closed system device.  

PubMed

The extent of airborne environmental bacterial contamination which occurs following tracheal suction has been investigated in patients undergoing intermittent positive pressure ventilation in the intensive therapy unit. Two methods of performing suction, one using a conventional open technique and one using a closed system (Stericath), have been compared. Significantly lower levels of environmental contamination were observed when the closed system was used. PMID:1750600

Cobley, M; Atkins, M; Jones, P L

1991-11-01

363

Potential environmental contaminant risks to avian species at importnat bird areas in the northeastern United States.  

PubMed

Environmental contaminants can have profound effects on birds, acting from the molecular through population levels of biological organization. An analysis of potential contaminant threats was undertaken at 52 Important Bird Areas (IBAs) within the northeastern Atlantic coast drainage. Using geographic information system methodology, data layers describing or integrating contamination (impaired waters, fish or wildlife consumption advisories, toxic release inventory sites, and estimates of pesticide use) were overlaid on buffered IBA boundaries, and the relative threat at each site was ranked. Some species of birds residing at Jefferson National Forrest (NF), Stewart B. McKinney National Wildlife Refuge (NWR), Great Dismal Swamp NWR, Blue Ridge Parkway, Shenandoah National Park (NP), Adirondack Park, Edwin B. Forsythe NWR, George Washington NF, Green Mountain NF, Long Island Piping Plover Beaches, and Merrymeeting Bay may be threatened by environmental contaminants. These sites exhibited moderate to high percentages of impaired waters and had fish consumption advisories related to mercury and polychlorinated biphenyls, and were located in counties with substantial pesticide use. Endangered, threatened, and Watch List bird species are present at these sites. The Contaminant Exposure and Effects-Terrestrial Vertebrates database was searched within buffered IBA boundaries, and for a moderate number of sites there was concordance between the perceived risk and contaminant exposure. Several of the IBAs with apparently substantial contaminant threats had no avian ecotoxicological data (e.g., George Washington NF, Shenandoah NP). Based upon this screening level risk assessment, contaminant biomonitoring of birds is warranted at such sites, and data generated from these efforts could foster natural resource management activities. PMID:18393576

Rattner, Barnett A; Ackerson, Betty K

2008-07-01

364

Environmental contamination associated with a marine landfill (‘seafill’) beside a coral reef  

Microsoft Academic Search

In Bermuda, bulk waste such as scrap metal, cars, etc., and blocks of cement-stabilized incinerator ash (produced from burning garbage) are disposed of in a foreshore reclamation site, i.e., a seafill. Chemical analyses show that seawater leaching out of the dump regularly exceeds water quality guidelines for Zn and Cu, and that the surrounding sediments are enriched in multiple contaminant

Ross Jones

2010-01-01

365

Are chemicals in articles an obstacle for reaching environmental goals? - Missing links in EU chemical management.  

PubMed

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

Molander, Linda; Breitholtz, Magnus; Andersson, Patrik L; Rybacka, Aleksandra; Rudén, Christina

2012-08-02

366

Environmental contamination by vancomycin resistant enterococci (VRE) in Swedish broiler production  

PubMed Central

Background Vancomycin resistant enterococci are a frequent cause of nosocomial infections and their presence among farm animals is unwanted. Using media supplemented with vancomycin an increase in the proportion of samples from Swedish broilers positive for vancomycin resistant enterococci has been detected. The situation at farm level is largely unknown. The aims of this study were to obtain baseline knowledge about environmental contamination with vancomycin resistant enterococci in Swedish broiler production and the association between environmental contamination and colonisation of birds. Methods Environmental samples were taken before, during and after a batch of broilers at three farms. Samples were cultured both qualitatively and semi-quantitatively for vancomycin resistant enterococci. In addition, caecal content from birds in the batch following at each farm was cultured qualitatively for vancomycin resistant enterococci. Results The number of samples positive for vancomycin resistant enterococci varied among the farms. Also the amount of vancomycin resistant enterococci in the positive samples and the proportion of caecal samples containing vancomycin resistant enterococci varied among the farms. Still, the temporal changes in environmental contamination followed a similar pattern in all farms. Conclusion Vancomycin resistant enterococci persist in the compartments even after cleaning and the temporal changes in environmental contamination were similar among farms. There were however differences among farms regarding both degree of contamination and proportion of birds colonized with vancomycin resistant enterococci. The proportion of colonized birds and the amount of vancomycin resistant enterococci in the compartments seems to be associated. If the factor(s) causing the differences among farms could be identified, it might be possible to reduce both the risk for colonisation by vancomycin resistant enterococci of the subsequent flock and the risk for spread of vancomycin resistant enterococci via the food chain to humans.

2009-01-01

367

A physical-chemical screening model for anticipating widespread contamination of community water supply wells by gasoline constituents.  

PubMed

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. PMID:15588575

Arey, J Samuel; Gschwend, Philip M

2005-01-01

368

A physical chemical screening model for anticipating widespread contamination of community water supply wells by gasoline constituents  

NASA Astrophysics Data System (ADS)

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.

Arey, J. Samuel; Gschwend, Philip M.

2005-01-01

369

Geographically distributed classification of surface water chemical parameters influencing fate and behavior of nanoparticles and colloid facilitated contaminant transport.  

PubMed

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

Hammes, Julia; Gallego-Urrea, Julián A; Hassellöv, Martin

2013-06-18

370

Ranking terrestrial vertebrate species for utility in biomonitoring and vulnerability to environmental contaminants.  

PubMed

The measurement of contaminant tissue concentrations or exposure-related effects in biota has been used extensively to monitor pollution and environmental health. Terrestrial vertebrates have historically been an important group of species in such evaluations, not only because many are excellent sentinels of environmental contamination, but also because they are valued natural resources in their own right that may be adversely affected by toxicant exposure. Selection of appropriate vertebrates for biomonitoring studies frequently relies on expert opinion, although a few rigorous schemes are in use for predicting vulnerability of birds to the adverse effects of petroleum crude oil. A Utility Index that ranks terrestrial vertebrate species as potential sentinels of contaminants in a region, and a Vulnerability Index that assesses the threat of specific groups of contaminants to these species, have been developed to assist decision makers in risk assessments of persistent organic pollutants, cholinesterase-inhibiting pesticides, petroleum crude oil, mercury, and lead shot. Twenty-five terrestrial vertebrate species commonly found in Atlantic Coast estuarine habitat (Rattner et al. 2001a) were ranked for their utility as biomonitors of contamination and their vulnerability to pollutants in this region. No single species, taxa, or class of vertebrates was found to be an ideal sentinel for all groups of contaminants. Although birds have overwhelmingly been used to monitor contaminants compared to other terrestrial vertebrate classes, the nonmigratory nature and dietary habits of the snapping turtle and mink consistently resulted in ranking these species as excellent sentinels as well. Vulnerability of Atlantic Coast populations of these species varied considerably among groups of contaminants. Usually a particular species was found to be at high risk to only one or two groups of contaminants, although a noteworthy exception is the bald eagle, which is highly vulnerable to all five of the contaminant groups examined. This index could be further enhanced by generation of additional comparative toxicity data to facilitate interspecific extrapolations. The Utility and Vulnerability Indices have application to many types of habitats in addition to estuaries and are of value to natural resource and risk managers that routinely conduct local, regional, or national environmental quality assessments. PMID:12442504

Golden, Nancy H; Rattner, Barnett A

2003-01-01

371

Environmental effects of dredging. Procedures for examining the relationship between sediment geochemistry and biological impacts of contaminants. Technical notes  

SciTech Connect

The relationship between sediment-bound contaminants and biological uptake of these contaminants is complex because of the many physical, chemical, and biological factors that can affect the relationship (McElroy and Means 1988). Operational and procedural problems encountered in determining how a sediment- associated contaminant affects aquatic organisms cause additional complications. If sediment quality criteria (SQC) are to be used to regulate dredged material disposal, prediction of biological responses based on changes in sediment geochemistry, i.e., sediment physical and chemical properties, and sediment contaminant levels must be possible. Radioactive tracers can be used to evaluate the effects of changing concentrations of sediment contaminants on aquatic organisms if the assumption can be made that the contaminant does not degrade during the study. Spiking a sediment with contaminants has generally been accomplished by the addition of organic solvent carriers containing the contaminant to the soil or sediment (Adams, pg1 2.)

Brannon, J.M.; McFarland, V.; Pennington, J.C.; Price, C.B.; Reilley, F.J.

1989-12-01

372

The decay of chemical weapons agents under environmental conditions  

SciTech Connect

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.

McGuire, R.R.; Haas, J.S.; Eagle, R.J.

1993-04-09

373

Genetic and physiological responses of flounder (Platichthys flesus) populations to chemical contamination in estuaries.  

PubMed

We sampled and analyzed European flounder (Platichthys flesus) from two highly contaminated estuaries (Seine and Loire, France) and one moderately contaminated estuary (reference site: Ster, France). Significant and convergent modifications of the allelic frequencies for the loci phosphoglucomutase (PGM), glucose phosphate isomerase 2 (GPI-2), mannose phosphate isomerase (MPI), and aspartate aminotransferase (AAT-2) were evident for fish in the contaminated sites versus fish from the reference site. Back-calculation from otoliths showed that the average growth rate of fish between the first and the second winter was greater at the reference site (approximately 150 mm/year) than at the contaminated sites (approximately 100 mm/year). Flounder from the reference site also had a higher condition factor (somatic wt/(fish length)3) compared to fish from the two contaminated sites. However, the observed pattern of growth rate and condition factor might be biased by particular environmental conditions other than contaminants and must be confirmed by more extensive study. Flow cytometry analysis of fish blood revealed a significant difference in the frequency of abnormal profiles for fish from the Seine (20%) versus from the Ster (3%). We interpret this result as a marked genotoxic effect of contaminants on fish in the Seine system. Some genotypes, such as PGM 85/85, appeared to be linked to the measured components of fitness, particularly to DNA integrity. Thus, these genotypes might be considered to be more tolerant to pollutants. The frequency of the PGM 85 allele was clearly elevated in flounder from the more contaminated sites, compared to flounder from the reference site. PMID:12463568

Laroche, Jean; Quiniou, Louis; Juhel, Guillaume; Auffret, Michel; Moraga, Dario

2002-12-01

374

The Chemical Technology Division at Argonne National Laboratory: Applying chemical innovation to environmental problems  

SciTech Connect

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.

NONE

1995-06-01

375

Environmental contaminants in freshwater fish and their risk to piscivorous wildlife based on a national monitoring program  

Microsoft Academic Search

Organochlorine chemical residues and elemental concentrations were measured in piscivorous and benthivorous fish at 111 sites\\u000a from large U.S. river basins. Potential contaminant sources such as urban and agricultural runoff, industrial discharges,\\u000a mine drainage, and irrigation varied among the sampling sites. Our objectives were to provide summary statistics for chemical\\u000a contaminants and to determine if contaminant concentrations in the fish

Jo Ellen Hinck; Christopher J. Schmitt; Kimberly A. Chojnacki; Donald E. Tillitt

2009-01-01

376

Role of expandable clays in the environmental fate of trinitrotoluene contamination. Final report  

SciTech Connect

A primary goal of the US military cleanup effort is to develop technologies that can expedite the remediation of explosive contaminants in soils. Nitroaromatic explosives are known to be strongly adsorbed by soils, with as much as 20 to 50 percent of radio-labeled explosives not extractable in controlled degradation studies. This suggests that adsorption of explosives and explosives degradation products onto soil components renders them unavailable to conventional extraction methods. The mechanism of sorption to soil components has been investigated in order to properly address the ultimate fate of explosives contamination. Trinitrotoluene undergoes reductive degradation in which nitro groups are animated to produce aminotoluene compounds. The final compound predicted by this reduction scheme is triaminotoluene. This reaction pathway results in intermediate degradation products of trinitrotoluene which act as weak bases. Protonation of these weak bases produces organic cations which are capable of sorption onto soil components. Sorption experiments were performed to determine the behavior of explosives and explosive by-products on pure clay minerals. X-ray diffraction studies measuring the interlamellar distance of expandable clays show an expansion as contaminants are bound to the clay, indicating displacement of interlayer cations. This intercalation of compounds of environmental interest within the interlamellar regions of expandable clays is an important geochemical event with implications toward a number of environmental disciplines including subsurface contaminant transport, risk assessment, contaminant bioavailability, site remediation, and natural attenuation.

Larson, S.L.; Weiss, C.A.; Martino, M.R.; Adams, J.W.

1998-07-01

377

Environmental risks of chemicals and genetically modified organisms: A comparison  

Microsoft Academic Search

The principles of precaution and sustainability require more consideration in the assessment of environmental risks posed\\u000a by chemicals and genetically modified organisms. Instead of applying risk reduction measures when there are serious indications\\u000a for damage, full scientific certainty is often waited for before taking action. The precautionary principle particularly should\\u000a be applied in those cases in which the extent and

Klaus Günter Steinhäuser

2001-01-01

378

Traditional food consumption behaviour and concern with environmental contaminants among Cree schoolchildren of the Mushkegowuk territory  

PubMed Central

Objectives To investigate factors influencing consumption of traditional foods (e.g. wild game, fish) and concerns about environmental contaminants among schoolchildren of the Mushkegowuk Territory First Nations (Moose Factory, Fort Albany, Kashechewan, Attawapiskat, and Peawanuck). Study design Cross-sectional data collection from a Web-based Eating Behaviour Questionnaire (WEB-Q). Methods Schoolchildren in grades 6–12 (n =262) responded to 4 of the WEB-Q questions: (a) Do you eat game? (b) How often do you eat game? (c) How concerned are you about the environmental contaminants in the wild game and fish that you eat? (d) I would eat more game if… [6 response options]. Data were collected in 2004 (Fort Albany), 2005 (Peawanuck), 2006 (Attawapiskat), 2007 (Moose Factory) and 2009 (Kashechewan). Hierarchical log-linear modelling (LLM) was used for analyses of multi-way frequency data. Results Of the schoolchildren answering the specific questions: 174 consumed game; 95 reported concerns about contaminants in game; and 84 would increase their game consumption if it were more available in their homes. LLM revealed significant differences between communities; schoolchildren in Moose Factory consumed game “rarely or never” at greater than expected frequency, and fewer than expected consumed game “at least once a day”. Schoolchildren in Kashechewan had greater frequency of daily game consumption and few were concerned about contaminants in game. Using LLM, we found that sex was an insignificant variable and did not affect game consumption frequency or environmental contaminant concern. Conclusion The consumption of traditional foods differed between communities and appears to be related to contamination concerns. In addition, latitudinal variation appears to influence the frequency of traditional food consumption in children; children in the most southerly location consumed traditional food less frequently.

Hlimi, Tina; Skinner, Kelly; Hanning, Rhona M; Martin, Ian D.; Tsuji, Leonard J.S.

2012-01-01

379

Predictive environmental risk assessment of chemical mixtures: a conceptual framework.  

PubMed

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

Backhaus, Thomas; Faust, Michael

2012-02-22

380

Environmental contaminants and the management of bat populations in the United States  

USGS Publications Warehouse

Food-chain residues of organochlorine pesticides probably have been involved in declines of some U.S. bat populations; examples include free-tailed bats at Carlsbad Cavern, New Mexico, and the endangered gray bat at sites in Missouri and Alabama. If a long-lived contaminant has not been dispersed in large amounts over large areas, its impact may be controlled by administrative action that stops its use or other environmental discharge, or that results in physical isolation of localized contamination so that it no longer enters food chains

Clark, D.R., Jr.

1988-01-01

381

Risk communication and public response to industrial chemical contamination in Sydney, Nova Scotia: a case study.  

PubMed

The town of Sydney, located on the north coast of Nova Scotia, is Canada's most contaminated community. The local tidal estuary, called the tar ponds, was used as a receptacle for industrial waste from a century of coke production and steel making and is estimated to contain more than 700,000 metric tons of polycyclic aromatic hydrocarbons, 50,000 metric tons of polychlorinated biphenyls, and many other residuals including arsenic, naphthalene, and toluene. Many residents have expressed consternation over the potential for exposure and subsequent health effects from the ponds. Recent epidemiological studies estimate a 30 to 40 percent increased incidence in several types of cancer within the community. This paper examines the claims and responses made by a variety of interested parties about the chemical contamination in Sydney. It also considers how those claims, in addition to a number of other mediating factors, may have influenced the local community in the mobilization of a response to the contamination. PMID:12491851

Rainham, Daniel

2002-12-01

382

Survey of Radiological and Chemical Contaminants in the Near-Shore Environment at the Hanford Site 300 Area  

SciTech Connect

This report describes an environmental surveillance study of the near-shore of the Columbia River at the 300 Area of the U.S. Department of Energy's Hanford Site. The study was conducted in August - October, 2001 to coincide with expected low river stage. The low river stage facilitated locating and sampling riverbank spring water and other media along the Columbia River shoreline. River water, riverbank spring water, near shore groundwater, riparian and aquatic biota samples were collected. Contaminants of concern included radionuclides, metals, organics, and anions. A survey of the external radiation levels along the near-shore area was also conducted. The report presents the objectives and regulatory drivers for this study, a description of the sample collection process, analytical results and discussion for both radiological and non-radiological (chemical) samples. In addition, human and ecological dose/risk assessments based upon the analytical results are presented.

Patton, Gregory W.; Tiller, Brett L.; Antonio, Ernest J.; Poston, Ted M.; Van Verst, Scott P.

2002-09-27

383

Prediction of contaminant persistence in aqueous phase: a quantum chemical approach.  

PubMed

At contaminated field sites where active remediation measures are not feasible, monitored natural attenuation is sometimes the only alternative for surface water or groundwater decontamination. However, due to slow degradation rates of some contaminants under natural conditions, attenuation processes and their performance assessment can take several years to decades to complete. Here, we apply quantum chemical calculations to predict contaminant persistence in the aqueous phase. For the test compound hexamethylphosphoramide (HMPA), P-N bond hydrolysis is the only thermodynamically favorable reaction that may lead to its degradation under reducing conditions. Through calculation of aqueous Gibbs free energies of activation for all potential reaction mechanisms, it is predicted that HMPA hydrolyzes via an acid-catalyzed mechanism at pH < 8.2, and an uncatalyzed mechanism at pH 8.2-8.5. The estimated half-lives of thousands to hundreds of thousands of years over the groundwater-typical pH range of 6.0 to 8.5 indicate that HMPA will be persistent in the absence of suitable oxidants. At pH 0, where the hydrolysis reaction is rapid enough to enable measurement, the experimentally determined rate constant and half-life are in excellent agreement with the predicted values. Since the quantum chemical methodology described herein can be applied to virtually any contaminant or reaction of interest, it is especially valuable for the prediction of persistence when slow reaction rates impede experimental investigations and appropriate QSARs are unavailable. PMID:21332222

Blotevogel, Jens; Mayeno, Arthur N; Sale, Tom C; Borch, Thomas

2011-02-20

384

Sediment chemical contamination and toxicity associated with a coastal golf course complex.  

PubMed

The increasing density of golf courses represents a potential source of sediment contamination to nearby coastal areas, the chemical and biological magnitude of which is almost unknown. The objective of this study was to determine the concentrations of contaminants and toxicities of sediments impacted by a coastal golf course complex. Sediment contaminant concentrations were determined at least twice during the two-year study period at 14 sampling stations. In addition, a combination of acute and chronic bioassays were conducted exposing four invertebrate test species to whole sediments and associated pore waters. Overall, the Florida, USA, golf course complex had a measurable impact on sediment chemical quality, particularly in near-field areas. Higher concentrations of several trace metals and organochlorine pesticides were detected in many golf course-associated sediments compared with reference areas; however, concentrations decreased seaward and only a few, primarily chlorinated pesticides, exceeded proposed sediment quality guidelines. Chromium, zinc, and mercury were detected more frequently than other trace metals. The DDT and associated metabolites, dieldrin and chlordane, were the more commonly detected organic contaminants. Acute toxicity was uncommon and occurred consistently for sediment collected from one coastal location. In contrast, chronic toxicity occurred at several study sites based on the response of Mysidopsis bahia. It was concluded that the impact of golf course runoff on sediment quality may be subtle and sensitive biological assessment methods, such as chronic toxicity tests, will be needed to detect adverse effects. PMID:11434280

Lewis, M A; Foss, S S; Harris, P S; Stanley, R S; Moore, J C

2001-07-01

385

Multimedia contaminant environmental exposure assessment methodology as applied to Los Alamos, New Mexico  

SciTech Connect

The MCEA (Multimedia Contaminant Environmental Exposure Assessment) methodology assesses exposures to air, water, soil, and plants from contaminants released into the environment by simulating dominant mechanisms of contaminant migration and fate. The methodology encompasses five different pathways (i.e., atmospheric, terrestrial, overland, subsurface, and surface water) and combines them into a highly flexible tool. The flexibility of the MCEA methodology is demonstrated by encompassing two of the pathways (i.e., overland and surface water) into an effective tool for simulating the migration and fate of radionuclides released into the Los Alamos, New Mexico region. The study revealed that: (a) the /sup 239/Pu inventory in lower Los Alamos Canyon increased by approximately 1.1 times for the 50-y flood event; (b) the average contaminant /sup 239/Pu concentrations (i.e., weighted according to the depth of the respective bed layer) in lower Los Alamos Canyon for the 50-y flood event decreased by 5.4%; (c) approx. 27% of the total /sup 239/Pu contamination resuspended from the entire bed (based on the assumed cross sections) for the 50-y flood event originated from lower Pueblo Canyon; (d) an increase in the /sup 239/Pu contamination of the bed followed the general deposition patterns experienced by the sediment in Pueblo-lower Los Alamos Canyon; likewise, a decrease in the /sup 239/Pu contamination of the bed followed general sediment resuspension patterns in the canyon; (e) 55% of the /sup 239/Pu reaching the San Ildefonso Pueblo in lower Los Alamos Canyon originated from lower Los Alamos Canyon; and (f) 56% of the /sup 239/Pu contamination reaching the San Ildefonso Pueblo in lower Los Alamos Canyon was carried through towards the Rio Grande. 47 references, 41 figures, 29 tables.

Whelan, G.; Thompson, F.L.; Yabusaki, S.B.

1983-02-01

386

Numerical Modeling of Contaminant Transport with Spatially-Dependent Dispersion and Non-Linear Chemical Reaction  

Microsoft Academic Search

A one-dimensional advective-dispersive contaminant transport model with scale-dependent dispersion coefficient in the presence of a nonlinea r chemical reaction of arbitrary order is considered. Two types of variations of the dispersion coefficient with the downstream distance are considered. The first type assumes that the d ispersivity increases as a polynomial function with distance while the other assumes an exponentially- increasing

A. J. Chamkha

2007-01-01

387

Sediment toxicity in the Hudson-Raritan estuary: Distribution and correlations with chemical contamination  

Microsoft Academic Search

The Hudson-Raritan Estuary is one of several United States coastal areas where chemical data have suggested a potential for\\u000a contaminant-related biological effects, and multiyear intensive bioeffects surveys have been conducted by the National Oceanic\\u000a and Atmospheric Administration. The severity and spatial patterns in sediment toxicity were determined in an estuary-wide\\u000a survey during spring 1991 using amphipods, bivalve larvae, and luminescent

Douglas A. Wolfe; Edward R. Long; Glen B. Thursby

1996-01-01

388

Application of ultrasonic irradiation for the degradation of chemical contaminants in water  

Microsoft Academic Search

The sonochemical degradation of a variety of chemical contaminants in aqueous solution has been investigated. Substrates such as chlorinated hydrocarbons, pesticides, phenols, explosives such as TNT, and esters are transformed into short-chain organic acids, CO2, and inorganic ions as the final products. Time scales of treatment in simple batch reactors over the frequency range of 20 to 500 kHz are

Michael R. Hoffmann; Inez Hua; Ralf Höchemer

1996-01-01

389

The impact of semiconductor, electronics and optoelectronic industries on downstream perfluorinated chemical contamination in Taiwanese rivers  

Microsoft Academic Search

This study provides the first evidence on the influence of the semiconductor and electronics industries on perfluorinated chemicals (PFCs) contamination in receiving rivers. We have quantified ten PFCs, including perfluoroalkyl sulfonates (PFASs: PFBS, PFHxS, PFOS) and perfluoroalkyl carboxylates (PFCAs: PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA) in semiconductor, electronic, and optoelectronic industrial wastewaters and their receiving water bodies (Taiwan's Keya,

Angela Yu-Chen Lin; Sri Chandana Panchangam; Chao-Chun Lo

2009-01-01

390

Chemical techniques for assessing bioavailability of sediment-associated contaminants: SPME versus Tenax extraction.  

PubMed

The traditional approach for predicting the risk of hydrophobic organic contaminants (HOCs) in sediment is to relate organic carbon normalized sediment concentrations to body residues or toxic effects to organisms. However, due to the multiple variables controlling bioavailability, this method has limitations. A matrix independent method of predicting bioavailability needs to be used in order to be universally applicable. Both chemical activity (freely dissolved chemical concentrations) measured by solid-phase microextraction (SPME) and bioaccessibility (rapidly desorbing fraction) estimated by Tenax extraction have been developed to predict bioavailability of sediment-associated HOCs. The objectives of this review are to summarize a number of studies using matrix-SPME or Tenax extraction to estimate bioavailability and/or toxicity of different classes of HOCs and evaluate the strengths and weakness of these two techniques. Although the two chemical techniques assess different components of the matrix, estimates obtained from both techniques have been correlated to organism body residues. The advantages of SPME fibers are their applicability for use in situ and their potential usage for a wide array of contaminants by selection of appropriate coatings. Single time-point Tenax extraction, however, is more time- and labor-effective. Tenax extraction also has lower detection limits, making it more applicable for highly toxic contaminants. This review also calls for additional research to evaluate the role of sequestrated contaminants and ingestion of sediment particles by organisms on HOC bioavailability. The use of performance reference compounds to reduce SPME sampling time and linking chemical based bioavailability estimates to toxicological endpoints are essential to expand the applications of these methods. PMID:21412561

You, Jing; Harwood, Amanda D; Li, Huizhen; Lydy, Michael J

2011-03-17

391

RESULTS FOR THE FOURTH QUARTER 2011 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS  

SciTech Connect

The Saltstone Facility is designed and permitted to immobilize and dispose of low-level radioactive and hazardous liquid waste (salt solution) remaining from the processing of radioactive material at the Savannah River Site. Low-level waste (LLW) streams from the Effluent Treatment Project (ETP), H-Canyon, and the decontaminated salt solution product from the Actinide Removal Process/Modular Caustic Side Solvent Extraction (CSSX) Unit (ARP/MCU) process are stored in Tank 50 until the LLW can be transferred to the Saltstone Facility for treatment and disposal. The LLW must meet the specified waste acceptance criteria (WAC) before it is processed into saltstone. The specific chemical and radionuclide contaminants and their respective WAC limits are in the current Saltstone WAC. Waste Solidification Engineering (WSE) requested that Savannah River National Laboratory (SRNL) perform quarterly analysis on saltstone samples. The concentrations of chemical and radionuclide contaminants are measured to ensure the saltstone produced during each quarter is in compliance with the current WAC. This report documents the concentrations of chemical and radionuclide contaminants for the 2011 Fourth Quarter samples collected from Tank 50 on October 12, 2011 and discusses those results in further detail than the previously issued results report.

Bannochie, C.

2012-01-31

392

RESULTS FOR THE THIRD QUARTER 2011 TANK 50 WAC SLURRY SAMPLE: CHEMICAL AND RADIONUCLIDE CONTAMINANT RESULTS  

SciTech Connect

The Saltstone Facility is designed and permitted to immobilize and dispose of low-level radioactive and hazardous liquid waste (salt solution) remaining from the processing of radioactive material at the Savannah River Site. Low-level waste (LLW) streams from the Effluent Treatment Project (ETP), H-Canyon, and the decontaminated salt solution product from the Actinide Removal Process/Modular Caustic Side Solvent Extraction (CSSX) Unit (ARP/MCU) process are stored in Tank 50 until the LLW can be transferred to the Saltstone Facility for treatment and disposal. The LLW must meet the specified waste acceptance criteria (WAC) before it is processed into saltstone. The specific chemical and radionuclide contaminants and their respective WAC limits are in the current Saltstone WAC. Waste Solidification Engineering (WSE) requested that Savannah River National Laboratory (SRNL) perform quarterly analysis on saltstone samples. The concentrations of chemical and radionuclide contaminants are measured to ensure the saltstone produced during each quarter is in compliance with the current WAC. This report documents the concentrations of chemical and radionuclide contaminants for the 2011 Third Quarter samples collected from Tank 50 on July 7, 2011 and discusses those results in further detail than the previously issued results report.

Reigel, M.

2011-10-20

393

REMOVAL OF MERCURY FROM CONTAMINATED SOILS AT THE PAVLODAR CHEMICAL PLANT.  

SciTech Connect

Soils beneath and adjacent to the Pavlodar Chemical Plant in Kazakhstan have been contaminated with elemental mercury as a result of chlor alkali processing using mercury cathode cell technology. The work described in this paper was conducted in preparation for a demonstration of a technology to remove the mercury from the contaminated soils using a vacuum assisted thermal distillation process. The process can operate at temperatures from 250-500 C and pressures of 0.13kPa-1.33kPa. Following vaporization, the mercury vapor is cooled, condensed and concentrated back to liquid elemental mercury. It will then be treated using the Sulfur Polymer Stabilization/Solidification process developed at Brookhaven National Laboratory as described in a companion paper at this conference. The overall project objectives include chemical and physical characterization of the contaminated soils, study of the influence of the soil's physical-chemical and hydro dynamical characteristics on process parameters, and laboratory testing to optimize the mercury sublimation rate when heating in vacuum. Based on these laboratory and pilot-scale data, a full-scale production process will be designed for testing. This paper describes the soil characterization. This work is being sponsored by the International Science and Technology Center.

KHRAPUNOV, V. YE.; ISAKOVA, R.A.; LEVINTOV, B.L.; KALB, P.D.; KAMBEROV, I.M.; TREBUKHOV, A.

2004-09-25

394

Environmental management of assembled chemical weapons assessment program.  

SciTech Connect

Environmental planning and management was an integral part of the ACWA Program planning process. To ensure that environmental protection issues could be addressed expeditiously and not delay the demonstrations, the PMACWA scaled the technology demonstrations such that simplified regulatory processes and existing research and development facilities could be used. The use of enclosed facilities for the demonstrations prevents any uncontrolled discharges to the environment and made it possible to conduct environmental assessments relatively quickly. The PMACWA also arranged for public briefings to ease any community concerns over the operations with chemical weapons. These steps precluded regulatory and community resistance to the ACWA activities. The cooperation of the regulators and stakeholders has been a key element in enabling the ACWA Program to move with the speed that it has to date. Technology demonstrations are currently underway and are scheduled to be completed in late May 1999. The data collected during these demonstrations will be used to prepare and submit a summary report to Congress by August 1999. The challenge continues for the ACWA management to guide the demonstrations to completion and to plan for possible pilot testing. As the scale of the ACWA facilities increase in size, the ease of reduced regulatory processes and environmental analyses will no longer be possible. However, the PMACWA will continue to explore all paths through the environmental process to speed the ACWA program to its goals while at the same time ensuring adequate protection of public health and safety and of the environment.

Frey, G.; Mohrman, G.; Templin, B. R.

1999-05-07

395

Using a site visit to a contaminated location as a focus for environmental health education for academic and public health nurses.  

PubMed

We describe a conference initiative that is distinguished by the use of a "community case study" to increase the knowledge and skills of nursing faculty and public health nurses in environmental health and to provide networking support to facilitate infusion of environmental health into nursing curricula and public health nursing practice. The Institute of Medicine's (1995) general environmental health competencies for nurses provided the conference framework. Woburn, Massachusetts, a Superfund site, served as the community case study to illustrate a complex environmental health problem. Over an extended period of time, Woburn was contaminated with multiple chemicals that eventually contaminated the drinking water supply; a cluster of childhood leukemia cases was linked subsequently to the Superfund site contaminants. A 6-hr interpreted walking and bus tour of the Superfund site enabled us to visit the premises of responsible parties, the vapor extraction fields, the capped Well H in the wooded wetlands, and to tour the affected neighborhood. This intensive, hands-on approach to learning environmental health content and skills that incorporated multiple learning strategies serves as a model for developing future conferences for public health nurses and nursing faculty. PMID:16961561

Backus, Ann S N; Hewitt, Jeanne Beauchamp; Chalupka, Stephanie M

396

Environmental chemical exposures and disturbances of heme synthesis.  

PubMed Central

Porphyrias are relatively uncommon inherited or acquired disorders in which clinical manifestations are attributable to a disturbance of heme synthesis (porphyrin metabolism), usually in association with endogenous or exogenous stressors. Porphyrias are characterized by elevations of heme precursors in blood, urine, and/or stool. A number of chemicals, particularly metals and halogenated hydrocarbons, induce disturbances of heme synthesis in experimental animals. Certain chemicals have also been linked to porphyria or porphyrinuria in humans, generally involving chronic industrial exposures or environmental exposures much higher than those usually encountered. A noteworthy example is the Turkish epidemic of porphyria cutanea tarda produced by accidental ingestion of wheat treated with the fungicide hexachlorobenzene. Measurements of excreted heme precursors have the potential to serve as biological markers for harmful but preclinical effects of certain chemical exposures; this potential warrants further research and applied field studies. It has been hypothesized that several otherwise unexplained chemical-associated illnesses, such as multiple chemical sensitivity syndrome, may represent mild chronic cases of porphyria or other acquired abnormalities in heme synthesis. This review concludes that, although it is reasonable to consider such hypotheses, there is currently no convincing evidence that these illnesses are mediated by a disturbance of heme synthesis; it is premature or unfounded to base clinical management on such explanations unless laboratory data are diagnostic for porphyria. This review discusses the limitations of laboratory measures of heme synthesis, and diagnostic guidelines are provided to assist in evaluating the symptomatic individual suspected of having a porphyria.

Daniell, W E; Stockbridge, H L; Labbe, R F; Woods, J S; Anderson, K E; Bissell, D M; Bloomer, J R; Ellefson, R D; Moore, M R; Pierach, C A; Schreiber, W E; Tefferi, A; Franklin, G M

1997-01-01

397

Environmental contamination associated with a marine landfill ('seafill') beside a coral reef.  

PubMed

In Bermuda, bulk waste such as scrap metal, cars, etc., and blocks of cement-stabilized incinerator ash (produced from burning garbage) are disposed of in a foreshore reclamation site, i.e., a seafill. Chemical analyses show that seawater leaching out of the dump regularly exceeds water quality guidelines for Zn and Cu, and that the surrounding sediments are enriched in multiple contaminant classes (metals, polycyclic aromatic hydrocarbons, petroleum hydrocarbons, dioxins and furans, polychlorinated biphenyls and an organochlorine pesticide), i.e., there is a halo of contamination. When compared against biological effects-based sediment quality guidelines (SQGs), numerous sediment samples exceeded the low-range values (where biological effects become possible), and for Hg and Zn exceeded the mid-range value (where they become probable). A few metres away from the edge of the 25 acre dump lies a small coral patch reef, proposed here as most contaminated coral reef in the world. PMID:20728189

Jones, Ross

2010-08-21

398

Discovery of environmental rhodamine B contamination in paprika during the vegetation process.  

PubMed

Recently, rhodamine B (RhB) in paprika and chilli has attracted much attention. Almost all the literature has deemed that the detectable RhB was attributed to malicious intents in the fabrication process. However, the occurrence of increasing cases with ultratrace levels of RhB was difficult to understand on the basis of that statement. Here, we report on the discovery of environmental RhB contamination in paprika during its vegetation process. Samples including paprika, soils, and stems collected from seven fields in the Xinjiang Region, China, were detected by ultraperformance liquid chromatography-tandem mass spectrometry. Far from any anthropogenic addition, the ultratrace RhB concentrations in all the paprika samples provided unambiguous evidence that environmental RhB contamination in paprika had really occurred over its growth period. Further illation suggests that the soil contaminated by RhB is one of the major contamination sources and that there may be a degradation of RhB in paprika during the late maturation stage. The discovery has significant implications for re-evaluating the origin of the RhB in paprika- and chilli-containing products. PMID:22524706

Lu, Qingguo; Gao, Wei; Du, Jingjing; Zhou, Li; Lian, Yunhe

2012-05-04

399

Thyroid disruption in walleye (Sander vitreus) exposed to environmental contaminants: cloning and use of iodothyronine deiodinases as molecular biomarkers.  

PubMed

Thyroid hormones play a role in the initiation of ovarian maturation in fish. Thus, reports of delayed sexual maturation in female walleye (Sander vitreus) exposed to contaminants in the Ottawa River suggest the presence of endocrine disrupting chemicals. The objectives of this study were to assess the effects of environmental contaminants in the Ottawa River on thyroid hormones of immature walleye and to develop a molecular biomarker of thyroid status. Walleye were sampled in the Ottawa River at Deep River (reference site), at Rivière Blanche (downstream from the Ottawa and Gatineau municipal wastewater treatment plants outflows), and at Plaisance (downstream from a pulp and paper mill). Plasma thyroid hormone levels were measured by radioimmunoassay. Walleye at Plaisance had two-fold elevated levels of thyroxine (T(4)) and 1.5-fold elevated levels triiodothyronine (T(3)), whereas the molar ratio of T(3):T(4) was reduced by over 50% compared to Deep River. Plasma T(3) levels were also elevated by approximately 1.5-fold at Rivière Blanche. Three iodothyronine deiodinases, a family of enzymes responsible for converting the prohormone T(4) to biologically active T(3), as well as for inactivating these two hormones, were partially cloned in walleye. A real-time PCR assay of deiodinase expression indicated that hepatic mRNA levels of type I and type III deiodinase were not modified between sites, whereas they were increased for type II deiodinase at Rivière Blanche as compared to the other sites. The response of this novel molecular transcript indicates a divergence with that expected based on the effects of experimentally induced hyperthyroidism on fish deiodinase expression; additional endpoints are therefore necessary to interpret changes in thyroid hormones levels in fish exposed to environmental contaminants. PMID:17524500

Picard-Aitken, Michelle; Fournier, Henri; Pariseau, Richard; Marcogliese, David J; Cyr, Daniel G

2007-04-22

400

Environmental Models and Computer Aided Decision Supports for the Comparative Assessment and Priority Setting among Environmental Chemicals.  

National Technical Information Service (NTIS)

Mathematical models which consider the most relevant environmental transport and transformation processes, were developed for the description of the environmental fate of chemicals. Three models regarding the behaviour in soil, surface waters and lower tr...

H. Rohleder M. Matthies J. Benz R. Brueggemann B. Muenzer

1986-01-01

401

Sea Urchin Embryotoxicity Test for Environmental Contaminants—Potential Role of the MRP Proteins  

Microsoft Academic Search

The main goals of this study were (1) to standardize a simple and reliable embryotoxicity test for environmental contaminants\\u000a and (2) to evaluate the presence and possible protective role of the multidrug resistance-associated (MRP) protein-mediated\\u000a multixenobiotic defense in two Mediterranean sea urchin species, Paracentrotus lividus and Arbacia lixula. Toxic end-point used was the success of the first cell division in

Ivana Bošnjak; Tanja Šegvi?; Tvrko Smital; Jasna Franeki?; Ivona Mladineo

2011-01-01

402

Specific Ribosomal DNA Sequences from Diverse Environmental Settings Correlate with Experimental Contaminants  

Microsoft Academic Search

Phylogenetic analysis of 16S ribosomal DNA (rDNA) clones obtained by PCR from uncultured bacteria inhabiting a wide range of environments has increased our knowledge of bacterial diversity. One possible problem in the assessment of bacterial diversity based on sequence information is that PCR is exquisitely sensitive to contaminating 16S rDNA. This raises the possibility that some putative environmental rRNA sequences

MICHAEL A. TANNER; BRETT M. GOEBEL; MICHAEL A. DOJKA; NORMAN R. PACE

1998-01-01

403

Environmental metabolomics: new insights into earthworm ecotoxicity and contaminant bioavailability in soil  

Microsoft Academic Search

Environmental metabolomics is a growing and emerging sub-discipline of metabolomics. Studies with earthworms have progressed\\u000a from the initial stages of simple contact exposure tests to detailed studies of earthworm responses in soil. Over the past\\u000a decade, a variety of endogenous metabolites have been identified as potential biomarkers of contaminant exposure. Furthermore,\\u000a metabolomic methods have delineated responses from sub-lethal exposure of

Myrna J. Simpson; Jennifer R. McKelvie

2009-01-01

404

Bioconcentration potential of organic environmental chemicals in humans  

SciTech Connect

A list of environmental chemicals detectable in adipose tissue and/or milk of non-occupationally exposed humans is presented. Besides their physiochemical properties (n-octanol/water partition coefficient and water solubility), their acceptable daily intake (ADI) values, production figures, fate in the environment, concentrations in human adipose tissue, and data from total diet studies from market basket investigations are given. Average bioconcentration factors (BCF) of polychlorinated biphenyls (PCBs), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), DDT, hexachlorobenzene (HCB), dieldrin, hexachlorocyclohexane isomers (alpha-HCH, beta-HCH, gamma-HCH, delta-HCH), pentachlorophenol (PCP), and 3,5-di-tert-butyl-4-hydroxytoluene (BHT) in human adipose tissue are calculated. The bioconcentration factors (wet wt basis) of these compounds are between 3 and 47 times higher in humans than in rats. The environmental chemicals are divided into three groups in respect to their bioconcentration factors in human adipose tissue: group I, high BCF (greater than 100); group II, medium BCF (10-100); and group III, low BCF (less than 10). The bioconcentration factors are useful for hazard assessment of chemicals to humans.

Geyer, H.; Scheunert, I.; Korte, F.

1986-12-01

405

Assessing the Extent of Sediment Contamination Around Creosote-treated Pilings Through Chemical and Biological Analyses  

NASA Astrophysics Data System (ADS)

Creosote is a common wood preservative used to treat marine structures, such as docks and bulkheads. Treated dock pilings continually leach polycyclic aromatic hydrocarbons (PAHs) and other creosote compounds into the surrounding water and sediment. Over time, these compounds can accumulate in marine sediments, reaching much greater concentrations than those in seawater. The purpose of this study was to assess the extent of creosote contamination in sediments, at a series of distances from treated pilings. Three pilings were randomly selected from a railroad trestle in Fidalgo Bay, WA and sediment samples were collected at four distances from each: 0 meters, 0.5 meters, 1 meter, and 2 meters. Samples were used to conduct two bioassays: an amphipod bioassay (Rhepoxynius abronius) and a sand dollar embryo bioassay. Grain size and PAH content (using a fluorometric method) were also measured. Five samples in the amphipod bioassay showed significantly lower effective survival than the reference sediment. These consisted of samples closest to the piling at 0 and 0.5 meters. One 0 m sample in the sand dollar embryo bioassay also showed a significantly lower percentage of normal embryos than the reference sediment. Overall, results strongly suggest that creosote-contaminated sediments, particularly those closest to treated pilings, can negatively affect both amphipods and echinoderm embryos. Although chemical data were somewhat ambiguous, 0 m samples had the highest levels of PAHs, which corresponded to the lowest average survival in both bioassays. Relatively high levels of PAHs were found as far as 2 meters away from pilings. Therefore, we cannot say how far chemical contamination can spread from creosote-treated pilings, and at what distance this contamination can still affect marine organisms. These results, as well as future research, are essential to the success of proposed piling removal projects. In addition to creosote-treated pilings, contaminated sediments must be removed and disposed of properly, in order to make future piling removals as effective and beneficial to ecosystem health as possible.

Stefansson, E. S.

2008-12-01

406

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

SciTech Connect

In April 1990, Wright-Patterson Air Force Base (WPAFB), initiated an investigation to evaluate a potential Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) removal action to prevent, to the extent practicable, the offsite migration of contaminated ground water from WPAFB. WPAFB retained the services of the Environmental Management Operations (EMO) and its principle subcontractor, International Technology Corporation (IT) to complete Phase 1 of the environmental investigation of ground-water contamination at WPAFB. Phase 1 of the investigation involves the short-term evaluation and potential design for a program to remove ground-water contamination that appears to be migrating across the western boundary of Area C, and across the northern boundary of Area B along Springfield Pike. Primarily, Task 4 of Phase 1 focuses on collection of information at the Area C and Springfield Pike boundaries of WPAFB. This Sampling and Analysis Plan (SAP) has been prepared to assist in completion of the Task 4 field investigation and is comprised of the Quality Assurance Project Plan (QAPP) and the Field Sampling Plan (FSP).

Not Available

1991-10-01

407

Chemical Analysis of Soils: An Environmental Chemistry Laboratory for Undergraduate Science Majors  

NASA Astrophysics Data System (ADS)

Successful management of conflicting uses of soils, which include food production as well as disposal of hazardous wastes, requires an understanding of soil characteristics that affect the mobility and fate of soil contaminants and nutrients. Soil chemistry, however, is often neglected in environmental chemistry courses. This laboratory exercise is designed to make this topic more accessible to instructors who teach environmental chemistry laboratories, as well as to their students. In this laboratory exercise, undergraduate science students evaluate soil samples for various parameters related to suitability for crop production and capability for retention of contaminants. The lab emphasizes the heterogeneous nature of soil and the difficulty of obtaining representative samples for analysis. One of the first steps in any chemical analysis is to obtain a representative analytical sample from a bulk sample, yet undergraduate students rarely do this in practice. In this lab, students attempt to obtain a representative analytical sample from a large soil sample. They compare their individual data with the mean and standard deviation compiled from the whole class. Soil water, calcium carbonate, organic matter, pH, and salinity are measured. Soil texture and octanol-water partitioning are demonstrated.

Willey, Joan D.; Avery, G. Brooks, Jr.; Manock, John J.; Skrabal, Stephen A.; Stehman, Charles F.

1999-12-01

408

Laboratory Evaluation of In Situ Chemical Oxidation for Groundwater Remediation, Test Area North, Operable Unit 1-07B, Idaho National Engineering and Environmental Laboratory, Volume One - Main Text and Appendices A and B  

Microsoft Academic Search

The laboratory investigation was performed to evaluate the feasibility of utilizing in situ chemical oxidation for remediating the secondary source of groundwater contaminants at the Idaho National Engineering and Environmental Laboratory (INEEL) Test Area North (TAN) Site. The study involved trichloroethene (TCE) contaminated media (groundwater, soil, and sludge) from TAN. The effectiveness of the selected oxidant, potassium permanganate (KMn0(sub4)), was

S. R. Cline; D. L. Denton; J. M. Giaquinto; M. K. McCracken; R. C. Starr

1999-01-01

409

Environmental contaminants and children's health: Cause for concern, time for action  

PubMed Central

The present paper provides an outline of the developmental and behavioural characteristics that make children, especially the fetus and young child, more vulnerable to contaminants than adults. The major categories of contaminants are briefly described. The evidence for their possible effects on neurobehavioural development; immune, endocrine and respiratory systems; childhood cancer based on research studies with animals; children exposed to catastrophic ‘accidents’ involving overdose exposures; and pregnant women and children from communities with high ‘background’ levels of contamination who participated in studies is reviewed. While the data are worrisome, especially for children living in northern and certain urban communities, much remains to be learned about possible subtle effects and the potential for long term effects of the current background contamination experienced by the majority of Canadian children before its significance to their health can be fully evaluated. The present regulatory processes, which are based on risk assessment, are so cumbersome and costly that the great majority of chemicals in use have not been fully evaluated, and the ingenuity of new chemical production continually exceeds the capacity to test the new chemicals. Moreover, despite past insistence on scientific proof of adverse effects and safety, unanticipated effects have occurred that will threaten the sustainability of human life unless more effective control measures are taken to limit the release of toxic substances and persistent chemicals into the environment. Therefore, the shortcomings of risk assessment are discussed, and the precautionary principle, which is used in some countries and is proposed for use internationally as an alternative measure that may offer improved control for the future, is outlined. Finally, opportunities for physician action are suggested.

Chance, Graham W

2001-01-01

410

Isotope Biomonitoring in Riverine Ecosystems: Tools for Understanding Linkages Between Environmental Contaminants and Basin Characteristics  

NASA Astrophysics Data System (ADS)

Concentrations of accumulative environmental contaminants (e.g., metals and organocholoro-pesticides) often exhibit wide temporal variations in riverine systems. Aquatic fauna, however, concentrate these contaminants into their biomass, providing a relatively long-term integrated record of water quality. In order to accurately determine how these contaminants are bioaccumulated within local food webs, it is essential to understand the relative trophic positions of the organisms assayed. Several studies have demonstrated that the influence of food-chain length on bioaccumulation of such contaminants can be estimated by using d15N. Comparison of d15N with concentration of these environmental toxins can be used to calculate biomagnification factors, which are useful in understanding toxin exposure pathways. While clear relations between isotopes and contaminants have been made in pelagic food webs, there is almost nothing known about these connections in riverine systems, which are almost certainly more complex. Biota in shallow rivers are significantly affected by active biogeochemical reactions taking place in the hyporheic and riparian zones, which affect the isotopic compositions of in situ productivity. Watershed characteristics, such as drainage basin size, regional climate and land use patterns will also contribute to the isotopic signals seen in these rivers. Additionally, anthropogenic inputs such as sewage effluent and agricultural runoff contribute to the complex nature of the biogeochemistry of these systems. We have piggybacked on several monitoring programs that collected and analyzed fish for metal and organocholoro-pesticide concentrations, and have analyzed archived fish samples for stable isotopic compositions. Our database is comprised of fish samples from 3 separate national-scale studies conducted within the last 15 years, including the BEST (Biomonitoring of Environmental Status and Trends), the NCBP (National Contaminant Bioaccumulation Program) and NAWQA (National Water Quality Assessment) sampling efforts. We have analyzed approximately 1200 individual fish samples for d13C and d15N, and a subset of approximately 300 fish for d34S. We hypothesize that variations in both riverine biogeochemistry and basin characteristics play the primary role in establishing the isotopic compositions of primary producers and ultimately riverine fish. Furthermore, we speculate that the causes of spatial variations in isotopic composition of aquatic biota (biochemical processing of nutrients, land-use differences, basin characteristics, etc.) are closely related to sources of variability in accumulative contaminant concentrations. Preliminary interpretations of this extensive dataset will be discussed.

Kendall, C.; Wankel, S. D.; Cabana, G.; Schmitt, C.

2002-05-01

411

Effects of organic and inorganic chemical contaminants on fertilization, hatching success, and prolarval survival of striped bass  

Microsoft Academic Search

The effects of an organic-inorganic chemical contaminant mixture were evaluated on percent fertilization, percent hatch, and prolarval survival of striped bass. All dilutions of the mixture simulated concentrations of various organic and inorganic contaminants found in striped bass spawning habitats. The organic contaminants were Aroclors® 1248, 1254, 1260, chlordane, DDE, chlordecone (kepone), toxaphene, anthracene, benzo(a)anthrene, chrysene, fluoranthrene, fluorene, perylene, pyrene,

Lenwood W. Hall; Larry O. Horseman; Scott Zeger

1984-01-01

412

Nevada National Security Site Environmental Remediation Progress Toward Closure of Contaminated Sites  

SciTech Connect

The Environmental Restoration activities at the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office assess the environmental impacts that resulted from atmospheric and underground nuclear tests conducted from 1951 to 1992 on the Nevada National Security Site and Nevada Test and Training Range (which includes the Tonopah Test Range). The goal is to protect public health and the environment through investigations and corrective actions. The Federal Facility Agreement and Consent Order (FFACO), established in 1996 between the State of Nevada Division of Environmental Protection (NDEP), DOE, and the U.S. Department of Defense, serves as the cleanup agreement for the Environmental Restoration activities and provides the framework for identifying, prioritizing, investigating, remediating, and monitoring contaminated sites. This agreement satisfies the corrective action requirements of the Resource Conservation and Recovery Act. To ensure efficiency in managing these corrective actions, the sites are grouped according to location, physical and geological characteristics, and/or contaminants. These groups, called corrective action units, are prioritized based on potential risk to workers and the public, available technology, future land use, agency and stakeholder concerns, and other criteria. Environmental Restoration activities include: Industrial Sites, Soils, and Underground Test Area. Nearly 15 years have passed since the FFACO was established, and during this time, more than 3,000 sites have been identified as requiring investigation or corrective actions. To date, approximately 1,945 sites have been investigated and closed through no further action, clean closure, or closure in place. Another 985 sites are currently being investigated or are in the remediation phase, leaving approximately 80 contaminated sites yet to be addressed.

Patrick Matthews (N-I) and Robert Boehlecke (NSO)

2011-03-03

413

An environmental rationale for retention of endangered chemicals  

SciTech Connect

Some of the chemicals being phased out to protect the stratospheric ozone layer offer offsetting benefits such as the potential to reduce global warming. This article discusses these two environmental issues together. Six scenarios were analyzed to assess the chlorine and bromine loading of HCFC-123, raising four major policy issues: using of single measure controls places excessive emphasis on the process rather than the objectives; the current Montreal Protocol, production is tantamount to emission, warrents reconsideration; phaseout of compounds based on GWPs will not resolve global warming concerns unless related emissions of greenhouse gases are also address, and careless elimination of options can be more harmful than beneficial. 8 refs., 2 figs.

Wuebbles, D.J. [Univ. of Illinois, Urbana, IL (United States); Calm, J.M.

1997-11-07

414

Effects of Toxic Environmental Contaminants on Voltage-Gated Calcium Channel Function: From Past to Present  

Microsoft Academic Search

Voltage-gated Ca2+ channels are targets of the number of naturally occurring toxins, therapeutic agents as well as environmental toxicants. Because of similarities of their chemical structure to Ca2+ in terms of hydrated ionic radius, electron orbital configuration, or other chemical properties, polyvalent cations from aluminum to zinc variously interact with multiple types of voltage-gated Ca2+ channels. These nonphysiological metals have

William D. Atchison

2003-01-01

415

Statement of the Committee on Military Environmental Research on the Status of Research into Biological Effects of Environmental Contaminants at Rocky Mountain Arsenal.  

National Technical Information Service (NTIS)

This report deals with the U.S. Army Medical Research and Development Command (USAMRDC) charge to establish environmental quality standards for the reclamation and renovation of contaminated land areas at military installations, and the Committee on Milit...

1977-01-01

416

Environmental hazard of cadmium, copper, lead and zinc in metal-contaminated soils remediated by sulfosuccinamate formulation.  

PubMed

Accumulation of metals in soil at elevated concentrations causes risks to the environmental quality and human health for more than one hundred million people globally. The rate of metal release and the alteration of metal distribution in soil phases after soil washing with a sulfosuccinamate surfactant solution (Aerosol 22) were evaluated for four contaminated soils. Furthermore, a sequential extraction scheme was carried out using selective extractants (HAcO, NH(2)OH·HCl, H(2)O(2) + NH(4)AcO) to evaluate which metal species are extracted by A22 and the alteration in metal distribution upon surfactant-washing. Efficiency of A22 to remove metals varied among soils. The washing treatment released up to 50% of Cd, 40% of Cu, 20% of Pb and 12% of Zn, mainly from the soluble and reducible soil fractions, therefore, greatly reducing the fraction of metals readily available in soil. Metal speciation analysis for the solutions collected upon soil washing with Aerosol 22 further confirmed these results. Copper and lead in solution were mostly present as soluble complexes, while Cd and Zn were present as free ions. Besides, redistribution of metals in soil was observed upon washing. The ratios of Zn strongly retained in the soil matrix and Cd complexed with organic ligands increased. Lead was mobilized to more weakly retained forms, which indicates a high bioavailability of the remaining Pb in soil after washing. Comprehensive knowledge on chemical forms of metals present in soil allows a feasible assessment of the environmental impact of metals for a given scenario, as well as possible alteration of environmental conditions, and a valuable prediction for potential leaching and groundwater contamination. PMID:21860854

del Carmen Hernández-Soriano, Maria; Peña, Aránzazu; Mingorance, M Dolores

2011-08-22

417

Implications and mitigation of model mismatch and covariance contamination for hyperspectral chemical agent detection  

NASA Astrophysics Data System (ADS)

Most chemical gas detection algorithms for long-wave infrared hyperspectral images assume a gas with a perfectly known spectral signature. In practice, the chemical signature is either imperfectly measured and/or exhibits spectral variability due to temperature variations and Beers law. The performance of these detection algorithms degrades further as a result of unavoidable contamination of the background covariance by the plume signal. The objective of this work is to explore robust matched filters that take the uncertainty and/or variability of the target signatures into account and mitigate performance loss resulting from different factors. We introduce various techniques that control the selectivity of the matched filter and we evaluate their performance in standoff LWIR hyperspectral chemical gas detection applications.

Niu, Sidi; Golowich, Steven E.; Ingle, Vinay K.; Manolakis, Dimitris G.

2013-02-01

418

Engineering evaluation/cost analysis for the proposed management of contaminated water impounded at the Weldon Spring chemical plant area.  

National Technical Information Service (NTIS)

This engineering evaluation/cost analysis (EE/CA) report has been prepared to support the proposed removal action for managing contaminated surface waters impounded at the chemical plant area of the Weldon Spring site, located near Weldon Spring, Missouri...

M. M. MacDonell M. L. Maxey J. M. Peterson I. E. Joya

1990-01-01

419

Disruption of Androgen Receptor Signaling in Males by Environmental Chemicals  

PubMed Central

Androgen-disruptors are environmental chemicals in that interfere with the biosynthesis, metabolism or action of endogenous androgens resulting in a deflection from normal male developmental programming and reproductive tract growth and function. Since male sexual differentiation is entirely androgen-dependent, it is highly susceptible to androgen-disruptors. Animal models and epidemiological evidence link exposure to androgen disrupting chemicals with reduced sperm counts, increased infertility, testicular dysgenesis syndrome, and testicular and prostate cancers. Further, there appears to be increased sensitivity to these agents during critical developmental windows when male differentiation is at its peak. A variety of in vitro and in silico approaches have been used to identify broad classes of androgen disrupting molecules that include organochlorinated pesticides, industrial chemicals, and plasticizers with capacity to ligand the androgen receptor. The vast majority of these synthetic molecules act as anti-androgens. This review will highlight the evidence for androgen disrupting chemicals that act through interference with the androgen receptor, discussing specific compounds for which there is documented in vivo evidence for male reproductive tract perturbations.

Luccio-Camelo, Doug C.; Prins, Gail S

2011-01-01

420

Disruption of androgen receptor signaling in males by environmental chemicals.  

PubMed

Androgen-disruptors are environmental chemicals in that interfere with the biosynthesis, metabolism or action of endogenous androgens resulting in a deflection from normal male developmental programming and reproductive tract growth and function. Since male sexual differentiation is entirely androgen-dependent, it is highly susceptible to androgen-disruptors. Animal models and epidemiological evidence link exposure to androgen disrupting chemicals with reduced sperm counts, increased infertility, testicular dysgenesis syndrome, and testicular and prostate cancers. Further, there appears to be increased sensitivity to these agents during critical developmental windows when male differentiation is at its peak. A variety of in vitro and in silico approaches have been used to identify broad classes of androgen disrupting molecules that include organochlorinated pesticides, industrial chemicals, and plasticizers with capacity to ligand the androgen receptor. The vast majority of these synthetic molecules act as anti-androgens. This review will highlight the evidence for androgen disrupting chemicals that act through interference with the androgen receptor, discussing specific compounds for which there is documented in vivo evidence for male reproductive tract perturbations. This article is part of a Special Issue entitled 'Endocrine disruptors'. PMID:21515368

Luccio-Camelo, Doug C; Prins, Gail S

2011-04-13

421

Use of solid phase characterisation and chemical modelling for assessing the behaviour of arsenic in contaminated soils  

Microsoft Academic Search

A soil, containing waste material from an industrially contaminated site, was found to be heavily contaminated with several heavy metals and As. A risk assessment for As leaching from this material has been carried out in several stages, collation and examination of historical records, solid-phase characterization and chemical modelling. The historical record indicates that the most probable source of As

D. G Lumsdon; J. C. L Meeussen; E Paterson; L. M Garden; P Anderson

2001-01-01

422

Effect of crude oil contamination on the yield and chemical composition of Pleurotus tuber-regium (Fr.) Singer  

Microsoft Academic Search

The effect of crude oil contamination which is a perennial problem in the Niger Delta of Nigeria on the yield and nutrient status of Pleurotus tuber-regium was investigated. In this study, after cultivating P. tuber-regium in crude oil contaminated soils to which sawdust, shredded banana leaf blades, NPK fertilizer and poultry litter were added, the yield and nutrient or chemical

Erute Magdalene; John Ariyo Okhuoya

2009-01-01

423

Contaminant and plant-derived changes in soil chemical and microbiological indicators during fuel oil rhizoremediation with Galega orientalis  

Microsoft Academic Search

The aim of this work was to evaluate the effects of vegetation and hydrocarbon (HC) contamination on the development of soil chemical and biological status during rhizoremediation of fuel oil contamination with the legume Galega orientalis. Uncontaminated and unvegetated references monitored in parallel with the rhizoremediation treatment enabled the identification of the partial effects. A 21-week greenhouse experiment simulated one

Anu Mikkonen; Elina Kondo; Kaisa Lappi; Kaisa Wallenius; Kristina Lindström; Helinä Hartikainen; Leena Suominen

2011-01-01

424

Chemical Residues and Contaminants in Foods of Animal Origin in Korea during the Past Decade.  

PubMed

Residues of veterinary drugs, pesticides, and environmental contaminants in domestic and imported foods of animal origin were monitored by the National Residue Program and inspection service in Korea in the past decade. In all, 134 substances were analyzed in the monitoring plan; 35 substances were examined in the surveillance and enforcement testing program, and 27 substances were investigated in exploratory projects. The overall trend of violation rates gradually decreased over the past decade. Pesticides were not found in any domestic samples of animal origin. The violation rates of chlortetracycline and oxytetracycline decreased, but quinolone and penicillin detections increased in Korea. Several kinds of residue violations of veterinary drugs, endosulfan, or dioxins were found in the imported products each year. In an example event in 2008, the Korea monitoring plan contributed globally to investigate the dioxin contamination from Chilean pork. Continuous monitoring based on internationally harmonized standards and methods provides the essential scientific basis to manage and ensure food safety. PMID:23402590

Kim, Meekyung; Cho, Byung-Hoon; Lim, Chae-Mi; Kim, Dong-Gyu; Yune, So Young; Shin, Jin Young; Bong, Young Hoon; Kang, Jeongwoo; Kim, Myeong-Ae; Son, Seong-Wan

2013-03-01

425

Chemical Genomics Profiling of Environmental Chemical Modulation of Human Nuclear Receptors  

PubMed Central

Background: The large and increasing number of chemicals released into the environment demands 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 testing, among which the quantitative high-throughput screening (qHTS) paradigm has been adopted as the primary tool for generating data from screening large chemical libraries using a wide spectrum of assays. Objectives: The goal of this study was to develop methods to evaluate the data generated from these assays to guide future assay selection and prioritization for the Tox21 program. Methods: We examined the data from the Tox21 pilot-phase collection of approximately 3,000 environmental chemicals profiled in qHTS format against a panel of 10 human nuclear receptors (AR, ER?, FXR, GR, LXR?, PPAR?, PPAR?, RXR?, TR?, and VDR) for reproducibility, concordance of biological activity profiles with sequence homology of the receptor ligand binding domains, and structure–activity relationships. Results: We determined the assays to be appropriate in terms of biological relevance. We found better concordance for replicate compounds for the agonist-mode than for the antagonist-mode assays, likely due to interference of cytotoxicity in the latter assays. This exercise also enabled us to formulate data-driven strategies for discriminating true signals from artifacts, and to prioritize assays based on data quality. Conclusions: The results demonstrate the feasibility of qHTS to identify the potential for environmentally relevant chemicals to interact with key toxicity pathways related to human disease induction.

Xia, Menghang; Cho, Ming-Hsuang; Sakamuru, Srilatha; Shinn, Paul; Houck, Keith A.; Dix, David J.; Judson, Richard S.; Witt, Kristine L.; Kavlock, Robert J.; Tice, Raymond R.; Austin, Christopher P.

2011-01-01

426

CONSIDERATIONS FOR DEVELOPING A DOSIMETRY-BASED CUMULATIVE RISK ASSESSMENT APPROACH FOR MIXTURES OF ENVIRONMENTAL CONTAMINANTS (Final Report)  

EPA Science Inventory

This final report, Considerations for Developing a Dosimetry-Based Cumulative Risk Assessment Approach for Mixtures of Environmental Contaminants , addresses the justification for developing physiologically based pharmacokinetic (PBPK) models for cumulative risk assessment....

427

The US EPA Geographic Information System for mapping environmental releases of toxic chemical release inventory (TRI) chemicals  

Microsoft Academic Search

This study characterizes the environmental releases of toxic chemicals of the Toxic Chemical Release Inventory (TRI) in the southeastern United States by using the US Environmental Protection Agency (EPA) Geographic Information System (GIS) to map them. These maps show that the largest quantities of TRI releases in the Southeast are usually near densely populated areas. This GIS mapping approach takes

John R. Stockwell; Jerome W. Sorensen; James W. Eckert; Edward M. Carreras

1993-01-01

428

Conventional weapons demilitarization: A health and environmental effects data base assessment: Propellants and their co-contaminants  

Microsoft Academic Search

The demilitarization of propellants by open burning results in the deposition of residues on soils. Residues can consist of the main ingredients in propellant formulations, namely, nitrocellulose, nitroglycerin, and nitroguanidine. Co-contaminants, consisting of plasticizers and stabilizers present in propellant formulations as well as environmental degradation products of the propellants, represent additional soil contaminants. These substances include nitrosoguanidine, dibutylphthlate, diethylphthlate, dipenylamine,

B. Mallon; D. Layton; R. Fish; P. Hsieh; L. Hall; L. Perry; G. Snyder

1988-01-01

429

Correlation between environmental relative moldiness index (ERMI) values in French dwellings and other measures of fungal contamination  

EPA Science Inventory

The Environmental Relative Moldiness Index (ERMI) is a DNA-based metric developed to describe the fungal contamination in US dwellings. Our goal was to determine if the ERMI values in dwellings in north western France were correlated with other measures of fungal contamination. D...

430

[Water environmental simulation of main contaminations in the Qiantang River at low water period].  

PubMed

Technical framework for water environment simulation of contaminations is established based on visualization and a spatial environmental model is built. The main two contaminations, namely NH: -N and TP, are simulated on the platform of MapInfo and Delft3D in the Qiantang River at the low water period, to analyze its space-time diversity. For NH4+ -N, the measured values are 0.19 mg/L and 0.66 mg/L larger than simulated values at the Lanjiang River mouth and the Yanlingwu, 0.16 mg/L, 0.54 mg/L and 0.49 mg/L smaller at the Zhaixi, the Yushan and the Yuanpu. For TP, the measured values are 0.13 mg/L and 0.14 mg/L higher than simulated values at the Meicheng Water facility and Yanlingwu. However, the measure values are slightly lower than simulated ones at Zhaixi, Yushan, Puyang River mouth and Yuanpu, the trend of which accords with actual situation. The results indicate that the contaminations of the Qiantang Reach mostly come from the Lanjiang River, the Fuchun River and the Puyang River on the upstream, among which the Lanjiang River and the Puyang River have a very high concentration of polluted materials, which means bad water quality, and influence the water downstream. The Lanjiang River becomes the chief contaminative source in the Fuchun River. When the discharge from the Xin'an River Dam is small, the recirculation region may be formed and makes part of the Xin'an Reach contaminated. Otherwise, when the discharge is large, the water quality in the Fuchun River is apparently improved. And the Puyang River, which brings the contaminations from the upstream, along with the polluted water let into it from the industries along the reach, has significant impacts on the water quality in Qiantang Reach. PMID:18290420

Xu, Li-qiang; Tong, Yang-bin; Lou, Zhang-hua; Cao, Fei-feng; Xu, Yue-ping

2007-12-01

431

Altered gonadal expression of TGF-? superfamily signaling factors in environmental contaminant-exposed juvenile alligators.  

PubMed

Environmental contaminant exposure can influence gonadal steroid signaling milieus; however, little research has investigated the vulnerability of non-steroidal signaling pathways in the gonads. Here we use American alligators (Alligator mississippiensis) hatched from field-collected eggs to analyze gonadal mRNA transcript levels of the activin-inhibin-follistatin gene expression network and growth differentiation factor 9. The eggs were collected from Lake Woodruff National Wildlife Refuge, a site with minimal anthropogenic influence, and Lake Apopka, a highly contaminated lake adjacent to a former EPA Superfund site. The hatchling alligators were raised for 13 months under controlled conditions, thus limiting differences to embryonic origins. Our data reveal sexually dimorphic mRNA expression in 13-month-old alligator gonads similar to patterns established in vertebrates with genetic sex determination. In addition, we observed a relationship between lake of origin and mRNA expression of activin/inhibin subunits ? and ?B, follistatin, and growth differentiation factor 9. Our study suggests that embryonic exposure to environmental contaminants can affect future non-steroidal signaling patterns in the gonads of a long-lived species. PMID:21251980

Moore, Brandon C; Milnes, Matthew R; Kohno, Satomi; Katsu, Yoshinao; Iguchi, Taisen; Woodruff, Teresa K; Guillette, Louis J

2011-01-18

432

Gene expression profiling and environmental contaminant assessment of migrating Pacific salmon in the Fraser River watershed of British Columbia  

Microsoft Academic Search

The health and physiological condition of anadromous salmon is of concern as their upriver migration requires navigation of human-impacted waterways and metabolism of stored energy reserves containing anthropogenic contaminants. Such factors may affect reproductive success of fish stocks. This study investigates chemical contaminant burdens and select gene expression profiles in Pacific Sockeye (Oncorhynchus nerka) and Chinook (Oncorhynchus tshawytscha) salmon which

Nik Veldhoen; Michael G. Ikonomou; Cory Dubetz; Nancy MacPherson; Tracy Sampson; Barry C. Kelly; Caren C. Helbing

2010-01-01

433

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

SciTech Connect

In April 1990, Wright-Patterson Air Force Base (WPAFB) initiated an effort for the evaluation of potential removal of ground water contamination at the Base. This report presents a current assessment of the nature and extent of the contamination believed to be migrating across the southwestern boundary of Area C and the northern boundary of Area B based upon analysis of existing environmental data obtained from several sources. The existing data base indicates widespread, low-level contamination moving across Base boundaries at levels that pose no immediate threat to the Mad River Valley well fields. An investigation by the City of Dayton in May and June 1990, however, implies that a more identifiable plume of PCE and TCE may be crossing the southwestern boundary of Area C immediately downgradient of Landfill 5. More data is needed to delineate ground water contamination and to design and implement a suitable control system. This report concludes that although an extensive study of the boundaries in question would be the preferred approach, a limited, focused investigation and subsequent feasibility study can be accomplished with a reasonable certainty of achieving the desired outcome of this project.

Not Available

1991-10-01

434

An evaluation of the ability of chemical measurements to predict polycyclic aromatic hydrocarbon-contaminated sediment toxicity to Hyalella azteca.  

PubMed

The present study examined the ability of three chemical estimation methods to predict toxicity and nontoxicity of polycyclic aromatic hydrocarbon (PAH) -contaminated sediment to the freshwater benthic amphipod Hyalella azteca for 192 sediment samples from 12 field sites. The first method used bulk sediment concentrations of 34 PAH compounds (PAH34), and fraction of total organic carbon, coupled with equilibrium partitioning theory to predict pore-water concentrations (KOC method). The second method used bulk sediment PAH34 concentrations and the fraction of anthropogenic (black carbon) and natural organic carbon coupled with literature-based black carbon-water and organic carbon-water partition coefficients to estimate pore-water concentrations (KOCKBC method). The final method directly measured pore-water concentrations (pore-water method). The U.S. Environmental Protection Agency's hydrocarbon narcosis model was used to predict sediment toxicity for all three methods using