Environmental factors, epigenetics, and developmental origin of reproductive disorders.

PubMed

Ho, Shuk-Mei; Cheong, Ana; Adgent, Margaret A; Veevers, Jennifer; Suen, Alisa A; Tam, Neville N C; Leung, Yuet-Kin; Jefferson, Wendy N; Williams, Carmen J

2017-03-01

Sex-specific differentiation, development, and function of the reproductive system are largely dependent on steroid hormones. For this reason, developmental exposure to estrogenic and anti-androgenic endocrine disrupting chemicals (EDCs) is associated with reproductive dysfunction in adulthood. Human data in support of "Developmental Origins of Health and Disease" (DOHaD) comes from multigenerational studies on offspring of diethylstilbestrol-exposed mothers/grandmothers. Animal data indicate that ovarian reserve, female cycling, adult uterine abnormalities, sperm quality, prostate disease, and mating behavior are susceptible to DOHaD effects induced by EDCs such as bisphenol A, genistein, diethylstilbestrol, p,p'-dichlorodiphenyl-dichloroethylene, phthalates, and polyaromatic hydrocarbons. Mechanisms underlying these EDC effects include direct mimicry of sex steroids or morphogens and interference with epigenomic sculpting during cell and tissue differentiation. Exposure to EDCs is associated with abnormal DNA methylation and other epigenetic modifications, as well as altered expression of genes important for development and function of reproductive tissues. Here we review the literature exploring the connections between developmental exposure to EDCs and adult reproductive dysfunction, and the mechanisms underlying these effects. Copyright © 2016 Elsevier Inc. All rights reserved.

Prenatal DDT and DDE Exposure and Child IQ in the CHAMACOS Cohort

PubMed Central

Gaspar, Fraser W.; Harley, Kim G.; Kogut, Katherine; Chevrier, Jonathan; Mora, Ana Maria; Sjödin, Andreas; Eskenazi, Brenda

2016-01-01

Although banned in most countries, dichlorodiphenyl-trichloroethane (DDT) continues to be used for vector control in some malaria endemic areas. Previous findings from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) cohort study found increased prenatal levels of DDT and its breakdown product dichlorodiphenyl-dichloroethylene (DDE) to be associated with altered neurodevelopment in children at 1 and 2 years of age. In this study, we combined the measured maternal DDT/E concentrations during pregnancy obtained for the prospective birth cohort with predicted prenatal DDT and DDE levels estimated for a retrospective birth cohort. Using generalized estimating equation (GEE) and linear regression models, we evaluated the relationship of prenatal maternal DDT and DDE serum concentrations with children’s cognition at ages 7 and 10.5 years as assessed using the Full Scale Intelligence Quotient (IQ) and 4 subtest scores (Working Memory, Perceptual Reasoning, Verbal Comprehension, and Processing Speed) of the Wechsler Intelligence Scale for Children (WISC). In GEE analyses incorporating both age 7 and 10.5 scores (n = 619), we found prenatal DDT and DDE levels were not associated with Full Scale IQ or any of the WISC subscales (p-value >0.05). In linear regression analyses assessing each time point separately, prenatal DDT levels were inversely associated with Processing Speed at age 7 years (n = 316), but prenatal DDT and DDE levels were not associated with Full Scale IQ or any of the WISC subscales at age 10.5 years (n = 595). We found evidence for effect modification by sex. In girls, but not boys, prenatal DDE levels were inversely associated with Full Scale IQ and Processing Speed at age 7 years. We conclude that prenatal DDT levels may be associated with delayed Processing Speed in children at age 7 years and the relationship between prenatal DDE levels and children’s cognitive development may be modified by sex, with girls being

Prenatal DDT and DDE exposure and child IQ in the CHAMACOS cohort.

PubMed

Gaspar, Fraser W; Harley, Kim G; Kogut, Katherine; Chevrier, Jonathan; Mora, Ana Maria; Sjödin, Andreas; Eskenazi, Brenda

2015-12-01

Although banned in most countries, dichlorodiphenyl-trichloroethane (DDT) continues to be used for vector control in some malaria endemic areas. Previous findings from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) cohort study found increased prenatal levels of DDT and its breakdown product dichlorodiphenyl-dichloroethylene (DDE) to be associated with altered neurodevelopment in children at 1 and 2years of age. In this study, we combined the measured maternal DDT/E concentrations during pregnancy obtained for the prospective birth cohort with predicted prenatal DDT and DDE levels estimated for a retrospective birth cohort. Using generalized estimating equation (GEE) and linear regression models, we evaluated the relationship of prenatal maternal DDT and DDE serum concentrations with children's cognition at ages 7 and 10.5years as assessed using the Full Scale Intelligence Quotient (IQ) and 4 subtest scores (Working Memory, Perceptual Reasoning, Verbal Comprehension, and Processing Speed) of the Wechsler Intelligence Scale for Children (WISC). In GEE analyses incorporating both age 7 and 10.5 scores (n=619), we found prenatal DDT and DDE levels were not associated with Full Scale IQ or any of the WISC subscales (p-value>0.05). In linear regression analyses assessing each time point separately, prenatal DDT levels were inversely associated with Processing Speed at age 7years (n=316), but prenatal DDT and DDE levels were not associated with Full Scale IQ or any of the WISC subscales at age 10.5years (n=595). We found evidence for effect modification by sex. In girls, but not boys, prenatal DDE levels were inversely associated with Full Scale IQ and Processing Speed at age 7years. We conclude that prenatal DDT levels may be associated with delayed Processing Speed in children at age 7years and the relationship between prenatal DDE levels and children's cognitive development may be modified by sex, with girls being more adversely

Photodissociation of cis-, trans-, and 1,1-dichloroethylene in the ultraviolet range: characterization of Cl((2)P(J)) elimination.

PubMed

Hua, Linqiang; Zhang, Xiaopeng; Lee, Wei-Bin; Chao, Meng-Hsuan; Zhang, Bing; Lin, King-Chuen

2010-01-14

By using photofragment velocity imaging detection coupled with a (2 + 1) resonance-enhanced multiphoton ionization technique, the elimination channel of spin-orbit chlorine atoms in photodissociation of cis-, trans-, and 1,1-dichloroethylene at two photolysis wavelengths of 214.5 and 235 nm is investigated. Translational energy and angular distributions of Cl((2)P(J)) fragmentation are acquired. The Cl((2)P(J)) fragments are produced by two competing channels. The fast dissociation component with higher translational energy is characterized by a Gaussian distribution, resulting from a curve crossing of the initially excited (pi, pi*) state to nearby repulsive (pi, sigma*) and/or (n, sigma*). In contrast, the slow component with a lower translational energy is characterized by a Boltzmann distribution, which dissociates on the vibrationally hot ground state relaxed from the (pi, pi*) state via internal conversion. cis-C(2)H(2)Cl(2) is found to have a larger branching of Boltzmann component than the other two isomers. The fraction of available energy partitioning into translation increases along the trend of cis- < trans- < 1,1-C(2)H(2)Cl(2). This trend may be fitted by a rigid radical model and interpreted by means of a torque generated during the C-Cl bond cleavage. The anisotropy parameters are determined, and the transition dipole moments are expected to be essentially along the C horizontal lineC bond axis. The results are also predicted theoretically. The relative quantum yields of Cl((2)P(J)) have a similar value for the three isomers at the two photolysis wavelengths.

Effect of p-amino-diphenyl ethers on hepatic microsomal cytochrome P450.

PubMed

Jiang, Huidi; Xuan, Guida

2003-09-01

The present paper aims to investigate whether p-amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether are inhibitors as well as inducers of P450. Mice were given daily intraperitoneal (ip) injections of p-amino-2',4'-dichlorodiphenyl ether (0.25 mmol/kg) or p-amino-4'-methyldiphenyl ether (0.25 mmol/kg) for 4 days and tested at 24 h and 48 h after the last dose injection. The results showed the mice pentobarbital sleeping time was shorter and the P450 content of hepatic microsome increased significantly in the group pretreated with p-amino-4'-methyldiphenyl ether when compared with the control group, while in mice pretreated with p-amino-2',4'-dichlorodiphenyl ether the hepatic microsome P450 content increased but the pentobarbital sleeping time was extended in clear contrast to the control group. The sleeping time of the phenobarbital group (80 mg/kg daily ip injection for 4 days) was shortened at 24 h after the last injection with increased P450 content of hepatic microsome, but it showed no difference at 48 h. The zoxazolamine-paralysis times of mice treated with p-amino-2',4'-dichlorodiphenyl ether were longer than those of the control mice, while the same dose of zoxazolamine did not lead to paralysis in mice pretreated with BNF. p-Amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether inhibited the activity of 7-ethoxyresorufin O-deethylase from rat hepatic microsome induced by BNF in vitro by 70.0% and 50.1% respectively. These results suggest that p-amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether are inhibitors as well as inducers of P450.

Potential occupational exposures in the Reiss-Engelhorn-Museen Mannheim/Germany.

PubMed

Musshoff, Frank; Gottsmann, Sandra; Mitschke, Sylvia; Rosendahl, Wilfried; Madea, Burkhard

2010-12-01

The Reiss-Engelhorn-Museen in Mannheim, Germany requested support from a toxicological laboratory in evaluating occupational exposures before a cleanup and renovation period in 2006. Samples of dust and dirt and scrapings of exhibits were collected from several locations. Following toxicologically relevant compounds could be identified by gas chromatography - mass spectrometry (GC/MS) by comparison with a mass spectra library: dichlorodiphenyl trichloroethane (DDT) and its breakdown product dichlorodiphenyl dichloroethane (DDD) as well as dichlorodiphenyl dichlorethylene (DDE), methoxychlor, nicotine, and camphor. In recent times various insecticides have been used to protect museum artefacts against moths, woodborers and other insect pests. Caution has to be made because the presence of hazardous compounds can result in security problems for museum staff as well as for visitors.

In utero exposure to persistent organic pollutants in relation to testicular cancer risk.

PubMed

Hardell, Lennart; Bavel, Bert; Lindström, Gunilla; Eriksson, Mikael; Carlberg, Michael

2006-02-01

Testicular cancer is the most common tumour type in young men. In Sweden the annual age-adjusted incidence increased significantly by 2.4% during the time period 1984-1993 and during 1994-2003 by 1.4%. Exposure to endocrine disrupting chemicals during the foetal period has been postulated to be a risk factor. In this investigation we studied the concentrations of chlorinated biphenyls (PCBs), p,p'-dichlorodiphenyl-dichloroethylene (pp'-DDE), hexachlorobenzene (HCB), chlordanes and polybrominated diphenylethers (PBDEs) in 58 cases with testicular cancer and 61 age-matched controls. Furthermore, case and control mothers were also asked to participate and 44 case mothers and 45 control mothers agreed. No significant differences were found between cases and controls. Case mothers had in general higher concentrations of these chemicals. For the sum of PCBs an odds ratio (OR) = 3.8, 95% confidence interval (CI) = 1.4-10 was calculated using the median concentration for the controls as cut-off value. For HCB OR = 4.4, CI = 1.7-12 and for PBDE OR = 2.5, 95% CI = 1.02-6.0 were obtained, whereas OR was not significantly increased for pp'-DDE and sum of chlordanes. The cases were born during a period with high concentrations of persistent organic pollutants (POPs) in humans. The decline of the increasing incidence of testicular cancer during recent years may reflect decreasing body burden of certain POPs since the 1980s.

Influence of nutrient amendments on the phytoextraction of weathered 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene by cucurbits.

PubMed

White, Jason C; Parrish, Zakia D; Isleyen, Mehmet; Gent, Martin P N; Iannucci-Berger, William; Eitzer, Brian D; Mattina, Maryjane Incorvia

2005-04-01

Field experiments were conducted to determine the impact of nutrient amendments on the phytoextraction of weathered 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (p,p '-DDE) by eight cultivars of cucurbits over a single growing season. Four cultivars of Cucurbita pepo ssp pepo are accumulators and extract percent level quantities of persistent organic pollutants (POPs), whereas C. pepo ssp ovifera and Cucumis sativus are nonaccumulators. The nonamended accumulators phytoextracted 1.0% of the p,p'-DDE and had a translocation factor of 0.44; however, the nonaccumulators removed 0.16% of the contaminant and had a translocation factor value of 0.09. The accumulators also had 3.8 times greater inorganic element content than the nonaccumulators. Duplicate mounds of each cultivar also received weekly nutrient amendments of phosphorus (400 mg/L K2HPO4), nitrogen (200 mg/L KNO3), or nitrogen/phosphorus (400 mg/L K2HPO4, 200 mg/L KNO3); a minus phosphorus treatment involved a 1-L addition of 1 g/L AlSO4 to the soil before planting. When normalized to respective control values (unamended vegetation), the root and stem p,p'-DDE bioconcentration factors (BCF) of the accumulator cultivars were significantly greater than those of the nonaccumulator cultivars under most nutrient regimes. The biomass of accumulator cultivars decreased by up to 61% under certain nutrient regimes, resulting in mixed effects on the amount of p,p'-DDE extracted. Treatment with N and P increased nonaccumulator biomass by 40 to 100%, and increased p,p'-DDE extraction from soil by 75%. Although generally assumed that fertilizer amendments will enhance phytoremediation, as evidenced here by the nonaccumulators, additions of macronutrients may reduce the phytoextraction of weathered POPs by C. pepo ssp pepo. These findings support our hypothesis that the ability of C. pepo ssp pepo to remove sequestered organic contaminants is governed by unique nutrient-acquisition mechanisms.

Methods for Minimization and Management of Variability in Long Term Groundwater Monitoring Results

DTIC Science & Technology

2015-06-01

procedure ACRONYMS AND ABBREVIATIONS (continued) vi TCE trichloroethylene trans-1,2-DCE trans-1,2-dichloroethylene USEPA U.S...following constituents: tetrachloroethylene (PCE), trichloroethylene (TCE), cis-1,2- dichloroethylene (cis-1,2-DCE), vinyl chloride (VC), and 1,1

MICROCOSM AND IN-SITU FIELD STUDIES OF ENHANCED BIOTRANSFORMATION OF TRICHLOROETHYLENE BY PHENOL-UTILIZING MICROORGANISMS

EPA Science Inventory

The ability of different aerobic groundwater microorganisms to cometabolically degrade trichloroethylene (TCE), 1,2-cis-dichloroethylene (c-DCE), and 1,2-trans-dichloroethylene (t-DCE) was evaluated both in groundwater-fed microcosms and in situ in a shallow aquifer. Microcosms a...

40 CFR Appendix Vii to Part 261 - Basis for Listing Hazardous Waste

Code of Federal Regulations, 2010 CFR

2010-07-01

... Tetrachloroethylene, methylene chloride trichloroethylene, 1,1,1-trichloroethane, carbon tetrachloride, chlorinated fluorocarbons. F002 Tetrachloroethylene, methylene chloride, trichloroethylene, 1,1,1-trichloroethane, 1,1,2...-dichloroethylene, 1,1-dichloroethylene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, 1,1,1,2...

Screening for estrogen and androgen receptor activities in 200 pesticides by in vitro reporter gene assays using Chinese hamster ovary cells.

PubMed Central

Kojima, Hiroyuki; Katsura, Eiji; Takeuchi, Shinji; Niiyama, Kazuhito; Kobayashi, Kunihiko

2004-01-01

We tested 200 pesticides, including some of their isomers and metabolites, for agonism and antagonism to two human estrogen receptor (hER) subtypes, hERalpha and hERbeta, and a human androgen receptor (hAR) by highly sensitive transactivation assays using Chinese hamster ovary cells. The test compounds were classified into nine groups: organochlorines, diphenyl ethers, organophosphorus pesticides, pyrethroids, carbamates, acid amides, triazines, ureas, and others. These pesticides were tested at concentrations < 10-5 M. Of the 200 pesticides tested, 47 and 33 showed hER- and hERbeta-mediated estrogenic activities, respectively. Among them, 29 pesticides had both hERalpha and hERbeta agonistic activities, and the effects of the organochlorine insecticides beta-benzene hexachloride (BHC) and delta-BHC and the carbamate insecticide methiocarb were predominantly hERbeta rather than hERalpha agonistic. Weak antagonistic effects toward hERalpha and hERbeta were shown in five and two pesticides, respectively. On the other hand, none of tested pesticides showed hAR-mediated androgenic activity, but 66 of 200 pesticides exhibited inhibitory activity against the transcriptional activity induced by 5alpha-dihydrotestosterone. In particular, the antiandrogenic activities of two diphenyl ether herbicides, chlornitrofen and chlomethoxyfen, were higher than those of vinclozolin and p,p -dichlorodiphenyl dichloroethylene, known AR antagonists. The results of our ER and AR assays show that 34 pesticides possessed both estrogenic and antiandrogenic activities, indicating pleiotropic effects on hER and hAR. We also discussed chemical structures related to these activities. Taken together, our findings suggest that a variety of pesticides have estrogenic and/or antiandrogenic potential via ER and/or AR, and that numerous other manmade chemicals may also possess such estrogenic and antiandrogenic activities. PMID:15064155

ABIOTIC NATURAL ATTENUATION OF CIS-DICHLOROETHYLENE AND 1,1-DICHLOROETHYLENE IN AQUIFER SEDIMENT

EPA Science Inventory

The disposal of TCE and 1,1,1-TCA at the Twin Cities Army Ammunition Plant (TCAAP) in Minnesota produced a plume of contaminated ground water that was over eight kilometers long. Although the size of the plume was consistent with a high ground water velocity in the aquifer and t...

Degradation of halogenated aliphatic compounds by the ammonia- oxidizing bacterium Nitrosomonas europaea.

PubMed

Vannelli, T; Logan, M; Arciero, D M; Hooper, A B

1990-04-01

Suspensions of Nitrosomonas europaea catalyzed the ammonia-stimulated aerobic transformation of the halogenated aliphatic compounds dichloromethane, dibromomethane, trichloromethane (chloroform), bromoethane, 1,2-dibromoethane (ethylene dibromide), 1,1,2-trichloroethane, 1,1,1-trichloroethane, monochloroethylene (vinyl chloride), gem-dichloroethylene, cis- and trans-dichloroethylene, cis-dibromoethylene, trichloroethylene, and 1,2,3-trichloropropane, Tetrachloromethane (carbon tetrachloride), tetrachloroethylene (perchloroethylene), and trans-dibromoethylene were not degraded.

Biodegradation of trichloroethylene by Methylosinus trichosporium OB3b.

PubMed Central

Tsien, H C; Brusseau, G A; Hanson, R S; Waclett, L P

1989-01-01

The methanotroph Methylosinus trichosporium OB3b, a type II methanotroph, degraded trichloroethylene at rates exceeding 1.2 mmol/h per g (dry weight) following the appearance of soluble methane monooxygenase in continuous and batch cultures. Cells capable oxidizing trichloroethylene contained components of soluble methane monooxygenase as demonstrated by Western blot (immunoblot) analysis with antibodies prepared against the purified enzyme. Growth of cultures in a medium containing 0.25 microM or less copper sulfate caused derepression of the synthesis of soluble methane monooxygenase. In these cultures, the specific rates of methane and methanol oxidation did not change during growth, while trichloroethylene oxidation increased with the appearance of soluble methane monooxygenase. M. trichosporium OB3b cells that contained soluble methane monooxygenase also degraded vinyl chloride, 1,1-dichloroethylene, cis-1,2-dichloroethylene, and trans-1,2-dichloroethylene. Images PMID:2515801

Health assessment for Stamina Mills Site, North Smithfield, Providence County, Rhode Island, Region 1. CERCLIS No. RID980731442. Preliminary report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1988-11-15

The Stamina Mills site is on the National Priorities List (NPL). The environmental contamination of concern consists of methylene chloride, chromium, lead, nickel, trichloroethylene, perchloroethylene, and 1,2-dichloro- ethylene in groundwater; trichloroethylene, 1,2-dichloroethylene, methylene chloride, and nickel in surface water; trichloroethylene, 1,2-dichloroethylene, chloroform, methylene chloride, cyanide, 2-butanone, cadmium, lead, chromium, nickel, and dieldrin in soil; and chloroform, lead, nickel, and chromium in sediment. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via soil, sediment, and surface water.

40 CFR 469.22 - Specialized definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Trichloroethane methylene chloride naphthalene 2 Nitrophenol phenol bis (2-ethylhexyl) phthalate...-butyl phthalate anthracene 1,2 Diphenylhydrazine isophorone butyl benzyl pthalate 1,1 Dichloroethylene 2...

40 CFR 469.22 - Specialized definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Trichloroethane methylene chloride naphthalene 2 Nitrophenol phenol bis (2-ethylhexyl) phthalate...-butyl phthalate anthracene 1,2 Diphenylhydrazine isophorone butyl benzyl pthalate 1,1 Dichloroethylene 2...

Determination of volatile organic hydrocarbons in water samples by solid-phase dynamic extraction.

PubMed

Jochmann, Maik A; Yuan, Xue; Schmidt, Torsten C

2007-03-01

In the present study a headspace solid-phase dynamic extraction method coupled to gas chromatography-mass spectrometry (HS-SPDE-GC/MS) for the trace determination of volatile halogenated hydrocarbons and benzene from groundwater samples was developed and evaluated. As target compounds, benzene as well as 11 chlorinated and brominated hydrocarbons (vinyl chloride, dichloromethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, carbon tetrachloride, chloroform, trichloroethylene, tetrachloroethylene, bromoform) of environmental and toxicological concern were included in this study. The analytes were extracted using a SPDE needle device, coated with a poly(dimethylsiloxane) with 10% embedded activated carbon phase (50-microm film thickness and 56-mm film length) and were analyzed by GC/MS in full-scan mode. Parameters that affect the extraction yield such as extraction and desorption temperature, salting-out, extraction and desorption flow rate, extraction volume and desorption volume, the number of extraction cycles, and the pre-desorption time have been evaluated and optimized. The linearity of the HS-SPDE-GC/MS method was established over several orders of magnitude. Method detection limits (MDLs) for the compounds investigated ranged between 12 ng/L for cis-dichloroethylene and trans-dichloroethylene and 870 ng/L for vinyl chloride. The method was thoroughly validated, and the precision at two concentration levels (0.1 mg/L and a concentration 5 times above the MDL) was between 3.1 and 16% for the analytes investigated. SPDE provides high sensitivity, short sample preparation and extraction times and a high sample throughput because of full automation. Finally, the applicability to real environmental samples is shown exemplarily for various groundwater samples from a former waste-oil recycling facility. Groundwater from the site showed a complex contamination with chlorinated volatile organic compounds and aromatic hydrocarbons.

Metabolism of halogenated ethylenes.

PubMed Central

Leibman, K C; Ortiz, E

1977-01-01

The metabolism of the chlorinated ethylenes may be explained by the formation of chloroethylene epoxides as the first intermediate products. The evidence indicates that these epoxides rearrange with migration of chlorine to form chloroacetaldehydes and chloroacetyl chlorides. Thus, monochloroacetic acid, chloral hydrate, and trichloroacetic acid have been found in reaction mixtures of 1,1-dichloroethylene, trichloroethylene, and tetrachloroethylene, respectively, with rat liver microsomal systems. Rearrangements of the chloroethylene, and glycols formed from the epoxides by hydration may also take place, but would appear, at least in the case of 1,1-dichloroethylene, to be quantitatively less important. The literature on the metabolism of chlorinated ethylenes and its relationship to their toxicity is reviewed. PMID:612463

40 CFR 469.22 - Specialized definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... trichloroethylene 2 Chlorophenol 2,4 Dichlorophenol 4 Nitrophenol pentachlorophenol di-n-butyl phthalate anthracene 1,2 Diphenylhydrazine isophorone butyl benzyl pthalate 1,1 Dichloroethylene 2,4,6 Trichlorophenol...

40 CFR 469.22 - Specialized definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... trichloroethylene 2 Chlorophenol 2,4 Dichlorophenol 4 Nitrophenol pentachlorophenol di-n-butyl phthalate anthracene 1,2 Diphenylhydrazine isophorone butyl benzyl pthalate 1,1 Dichloroethylene 2,4,6 Trichlorophenol...

Evaluation of HCFC AK 225 Alternatives for Precision Cleaning and Verification

NASA Technical Reports Server (NTRS)

Melton, D. M.

1998-01-01

Maintaining qualified cleaning and verification processes are essential in an production environment. Environmental regulations have and are continuing to impact cleaning and verification processing in component and large structures, both at the Michoud Assembly Facility and component suppliers. The goal of the effort was to assure that the cleaning and verification proceeds unimpeded and that qualified, environmentally compliant material and process replacements are implemented and perform to specifications. The approach consisted of (1) selection of a Supersonic Gas-Liquid Cleaning System; (2) selection and evaluation of three cleaning and verification solvents as candidate alternatives to HCFC 225 (Vertrel 423 (HCFC), Vertrel MCA (HFC/1,2-Dichloroethylene), and HFE 7100DE (HFE/1,2 Dichloroethylene)); and evaluation of an analytical instrumental post cleaning verification technique. This document is presented in viewgraph format.

MICROEMULSION OF MIXED CHLORINATED SOLVENTS USING FOOD GRADE (EDIBLE) SURFACTANTS

EPA Science Inventory

Ground water contamination frequently consists of mixed chlorinated solvents [e.g., tetrachloroethylene (PCE), trichloroethylene (TCE), and trans-1,2- dichloroethylene (DCE)]. In this research, mixtures of the food grade (edible) surfactants bis(2-ethylhexyl) sodium sulfosuccinat...

Methylsulfone polychlorinated biphenyl and 2,2-bis(chlorophenyl)-1,1-dichloroethylene metabolites in beluga whale (Delphinapterus leucas) from the St. Lawrence River estuary and western Hudson Bay, Canada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Letcher, R.J.; Norstrom, R.J.; Muir, D.C.G.

2000-05-01

Knowledge is limited regarding methylsulfone (MeSO{sub 2})-polychlorinated biphenyl (PCB), and especially MeSo{sub 2}-2,2-bis(chlorophenyl)-1,1-dichloroethylene (DDE), metabolites in cetacean species. The authors hypothesized that the ability of beluga whale (Delphinapterus leucas) to biotransform PCB and DDE compounds, and to form and degrade their MeSO{sub 2}-PCB and -DDE metabolites, is related to the capacity for xenobiotic metabolism. Adipose biopsies were collected from male and female beluga whale from distinct populations in the St. Lawrence River estuary (STL) and western Hudson Bay (WHB), Canada, which are contrasted by the exposure to different levels of cytochrome P450 enzyme-inducing, chlorinated hydrocarbon contaminants. The PCBs, DDTs, DDEs,more » 28 MeSO{sub 2} metabolites of 14 meta-para chlorine-unsubstituted PCBs, and four MeSO{sub 2} metabolites of 4,4{prime}- and 2,4{prime}-DDE were determined. The mean concentrations of total ({Sigma}-) MeSO{sub 2}-PCB in male STL beluga (230 ng/g), and ratios of {Sigma}-MeSO{sub 2}-PCB to {Sigma}-PCB (0.05) and {Sigma}-precursor-PCB (0.17) were approximately twofold higher, whereas the {Sigma}-precursor-PCB to {Sigma}-PCB ratio was approximately twofold lower, than in male WHB beluga. Both populations had a low formation capacity for MeSO{sub 2}-PCBs with {le} six chlorines (<4% of {Sigma}-MeSO{sub 2}-PCBs). The congener patterns were dominated by trichloro- and tetrachloro-MeSO{sub 2}-PCBs, and tetrachloro- and pentachloro-MeSO{sub 2}-PCBs in WHB and STL animals, respectively. In addition to 2- and 3-MeSO{sub 2}-4,4{prime}-DDE, two unknown MeSO{sub 2}-2,4{prime}-DDEs were detected. The mean 3-MeSO{sub 2}-4,4{prime}-DDE concentration in STL beluga (1.2 ng/g) was much greater than in WHB animals. The concentrations of 4,4{prime}-DDE, and not 3-MeSO{sub 2}-4,4{prime}-DDE, increased with age in male STL animals. The authors demonstrated that sulfone formation and clearance is related to metabolic capacity, and

FRACTIONATION OF STABLE CARBON ISOTOPES DURING ABIOTIC TRANSFORMATION OF TCE

EPA Science Inventory

At a Superfund Site in Minnesota, ground water is contaminated with trichloroethylene (TCE) with the contaminant plume stretching over five miles long. The ground water is iron and manganese reducing, and the complete absence of dichloroethylene, vinyl chloride, and ethene in th...

Cometabolic degradation of chlorinated alkenes by alkene monooxygenase in a propylene-grown Xanthobacter strain.

PubMed Central

Ensign, S A; Hyman, M R; Arp, D J

1992-01-01

Propylene-grown Xanthobacter cells (strain Py2) degraded several chlorinated alkenes of environmental concern, including trichloroethylene, 1-chloroethylene (vinyl chloride), cis- and trans-1,2-dichloroethylene, 1,3-dichloropropylene, and 2,3-dichloropropylene. 1,1-Dichloroethylene was not degraded efficiently, while tetrachloroethylene was not degraded. The role of alkene monooxygenase in catalyzing chlorinated alkene degradations was established by demonstrating that glucose-grown cells which lack alkene monooxygenase and propylene-grown cells in which alkene monooxygenase was selectively inactivated by propyne were unable to degrade the compounds. C2 and C3 chlorinated alkanes were not oxidized by alkene monooxygenase, but a number of these compounds were inhibitors of propylene and ethylene oxidation, suggesting that they compete for binding to the enzyme. A number of metabolites enhanced the rate of degradation of chlorinated alkenes, including propylene oxide, propionaldehyde, and glucose. Propylene stimulated chlorinated alkene oxidation slightly when present at a low concentration but became inhibitory at higher concentrations. Toxic effects associated with chlorinated alkene oxidations were determined by measuring the propylene oxidation and propylene oxide-dependent O2 uptake rates of cells previously incubated with chlorinated alkenes. Compounds which were substrates for alkene monooxygenase exhibited various levels of toxicity, with 1,1-dichloroethylene and trichloroethylene being the most potent inactivators of propylene oxidation and 1,3- and 2,3-dichloropropylene being the most potent inactivators of propylene oxide-dependent O2 uptake. No toxic effects were seen when cells were incubated with chlorinated alkenes anaerobically, indicating that the product(s) of chlorinated alkene oxidation mediates toxicity. PMID:1444418

Determination of adsorption isotherms of chlorinated hydrocarbons on halloysite adsorbent by inverse gas chromatography.

PubMed

Czech, K; Słomkiewicz, P M

2013-05-03

Inverse gas chromatographic methods of isotherm determination peak maximum (PM) and peak division (PD) were compared. These methods were applied to determine adsorption isotherms of dichloroethylene, trichloroethylene and tetrachloroethylene on acid-activated halloysite and adsorption enthalpy. Copyright © 2013 Elsevier B.V. All rights reserved.

40 CFR Table 7 to Subpart Vvvvvv... - Partially Soluble HAP

Code of Federal Regulations, 2013 CFR

2013-07-01

.... Methylene chloride 75092 43. N-hexane 110543 44. N,N-dimethylaniline 121697 45. Naphthalene 91203 46...-Dichloroethylene (vinylidene chloride) 75354 5. 1,2-Dibromoethane 106934 6. 1,2-Dichloroethane (ethylene dichloride.... Acrolein 107028 15. Acrylonitrile 107131 16. Allyl chloride 107051 17. Benzene 71432 18. Benzyl chloride...

40 CFR Table 7 to Subpart Vvvvvv... - Partially Soluble HAP

Code of Federal Regulations, 2014 CFR

2014-07-01

.... Methylene chloride 75092 43. N-hexane 110543 44. N,N-dimethylaniline 121697 45. Naphthalene 91203 46...-Dichloroethylene (vinylidene chloride) 75354 5. 1,2-Dibromoethane 106934 6. 1,2-Dichloroethane (ethylene dichloride.... Acrolein 107028 15. Acrylonitrile 107131 16. Allyl chloride 107051 17. Benzene 71432 18. Benzyl chloride...

40 CFR Table 7 to Subpart Vvvvvv... - Partially Soluble HAP

Code of Federal Regulations, 2012 CFR

2012-07-01

.... Methylene chloride 75092 43. N-hexane 110543 44. N,N-dimethylaniline 121697 45. Naphthalene 91203 46...-Dichloroethylene (vinylidene chloride) 75354 5. 1,2-Dibromoethane 106934 6. 1,2-Dichloroethane (ethylene dichloride.... Acrolein 107028 15. Acrylonitrile 107131 16. Allyl chloride 107051 17. Benzene 71432 18. Benzyl chloride...

Anaerobic biodegradation and hydrogeochemical controls on natural attenuation of trichloroethene in an inland forested wetland

USGS Publications Warehouse

Lorah, M.M.; Dyer, L.J.; Burris, D.R.

2007-01-01

Anaerobic biodegradation was conducted in a forested wetland where a plume of trichloroethylene discharges from a sand aquifer through organic-rich wetland and stream-bottom sediments. The rapid response of the wetland hydrology to precipitation events altered groundwater flow and geochemistry during wet conditions in the spring compared to the drier conditions in the summer and fall. During dry conditions, partial reductive dechlorination of trichloroethylene to cis-1,2-dichloroethylene occurred in methanogenic wetland porewater. Influx of oxygenated recharge during wet conditions led to a change from methanogenic to iron-reducing conditions and a lack of 1,2-dichloroethylene production in the wet spring conditions. During these wet conditions, dilution was the primary attenuation mechanism evident for trichloroethylene in the wetland porewater. Trichloroethylene degradation was insignificant in anaerobic microcosms constructed with the shallow wetland sediment. Natural attenuation of chlorinated solvents by anaerobic biodegradation may not be efficient at all wetland sites, despite organic-rich characteristics of the sediment.

Metabolism and mutagenicity of halogenated olefins--a comparison of structure and activity.

PubMed Central

Henschler, D

1977-01-01

Chlorinated ethylenes are metabolized in mammals, as a first step, to epoxides. The fate of these electrophilic intermediates may be reaction with nucleophiles (alkylation), hydrolysis, or intramolecular rearrangement. The latter reaction has been studied in the whole series of chlorinated epoxiethanes. The rearrangement products found were: acyl chlorides (tetrachloro-, trichloro-, and 1,1-dichloroethylenes), or chlorinated aldehydes (1,2-dichloroethylenes, cis- and trans-, vinyl chloride). The metabolities found in vivo are identical with, or further derivatives of these rearrangment products, with one important exception: trichloroethylene. With this compound, in vivo rearrangement yields chloral exclusively. The mechanism of the different rearrangement has been identified as a Lewis acid catalysis. All chlorinated ethylenes have been investigated in a tissue-mediated mutagenicity testing system. The prominent molecular feature of those with mutagenic effects (trichloro-, 1,1-dichloro-, and monochloroethylene) is unsymmetric chlorine substitution which renders the epoxides unstable, whereas symmetric substitution confers relative stability and nonmutagenic property. PMID:348459

40 CFR Appendix I to Part 257 - Maximum Contaminant Levels (MCLs)

Code of Federal Regulations, 2012 CFR

2012-07-01

... Drinking Water Act Chemical CAS No. MCL -(mg/l) Arsenic 7440-38-2 0.05 Barium 7440-39-3 1.0 Benzene 71-343... 107-06-2 0.005 1,1-Dichloroethylene 75-35-4 0.007 Endrin 75-20-8 0.0002 Fluoride 7 4.0 Lindane 58-89-9...

40 CFR Appendix I to Part 257 - Maximum Contaminant Levels (MCLs)

Code of Federal Regulations, 2011 CFR

2011-07-01

... Drinking Water Act Chemical CAS No. MCL -(mg/l) Arsenic 7440-38-2 0.05 Barium 7440-39-3 1.0 Benzene 71-343... 107-06-2 0.005 1,1-Dichloroethylene 75-35-4 0.007 Endrin 75-20-8 0.0002 Fluoride 7 4.0 Lindane 58-89-9...

40 CFR Appendix I to Part 257 - Maximum Contaminant Levels (MCLs)

Code of Federal Regulations, 2013 CFR

2013-07-01

... Drinking Water Act Chemical CAS No. MCL -(mg/l) Arsenic 7440-38-2 0.05 Barium 7440-39-3 1.0 Benzene 71-343... 107-06-2 0.005 1,1-Dichloroethylene 75-35-4 0.007 Endrin 75-20-8 0.0002 Fluoride 7 4.0 Lindane 58-89-9...

40 CFR Appendix I to Part 257 - Maximum Contaminant Levels (MCLs)

Code of Federal Regulations, 2014 CFR

2014-07-01

... Drinking Water Act Chemical CAS No. MCL -(mg/l) Arsenic 7440-38-2 0.05 Barium 7440-39-3 1.0 Benzene 71-343... 107-06-2 0.005 1,1-Dichloroethylene 75-35-4 0.007 Endrin 75-20-8 0.0002 Fluoride 7 4.0 Lindane 58-89-9...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Last, G.V.; Eddy, P.A.; Airhart, S.P.

The information presented in this report was collected during limited site investigation activities conducted in the vicinity of Landfills 1 and 4 at Fort Lewis. The purpose of this work was to provide a means of detecting and evaluating the impacts of these inactive landfills on ground-water quality and adjacent lands. This effort included the design and construction of ground-water monitoring systems for compliance with applicable federal and state regulations governing Resource Conservation and Recovery Act (RCRA)-type landfills. Ground-water samples were collected from both existing (1981 and 1984) wells and the newly installed (1988) wells. The analytical results from themore » water samples indicate that the ground water in and around Landfill 1 contains limited contamination. Contaminants may include volatile organic compounds and nitrate. The primary concern in the area around Landfill 1 was the determination that ground water from two wells may contain cis-1,2-dichloroethylene and 1,1,1-trichloroethylene above drinking water standards. Nitrate levels in the downgradient wells were greater than those in upgradient wells and exceeded drinking water standards in some of the less-representative samples. Analyses of ground-water samples from wells in and around Landfill 4 indicate several contaminants may be present. These include volatile organic compounds (principally cis-1,2-dichloroethylene and 1,1,1-trichloroethylene), coliform, oil and grease, and perhaps some metals (iron and magnesium). The primary concern in the area around Landfill 4 was the determination that ground water from five wells contained cis-1,2-dichloroethylene and 1,1,1-trichloroethylene above drinking water standards. The source of contaminants beneath either landfill cannot yet be identified. Insufficient data exist to disprove or confirm either landfill as possible contributors. 19 refs., 32 figs., 17 tabs.« less

Characterization of Chloroethylene Dehalogenation by Cell Extracts of Desulfomonile tiedjei and Its Relationship to Chlorobenzoate Dehalogenation

PubMed Central

Townsend, G. T.; Suflita, J. M.

1996-01-01

We characterized the reductive dehalogenation of tetrachloroethylene in cell extracts of Desulfomonile tiedjei and compared it with this organism's 3-chlorobenzoate dehalogenation activity. Tetrachloroethylene was sequentially dehalogenated to trichloro- and dichloroethylene; there was no evidence for dichloroethylene dehalogenation. Like the previously characterized 3-chlorobenzoate dehalogenation activity, tetrachloroethylene dehalogenation was heat sensitive, not oxygen labile, and increased in proportion to the amount of protein in assay mixtures. In addition, both dehalogenation activities were dependent on hydrogen or formate as an electron donor and had an absolute requirement for either methyl viologen or triquat as an electron carrier in vitro. Both activities appear to be catalyzed by integral membrane proteins with similar solubilization characteristics. Dehalogenation of tetrachloroethylene was inhibited by 3-chlorobenzoate but not by the structural isomers 2- and 4-chlorobenzoate. The last two compounds are not substrates for D. tiedjei. These findings lead us to suggest that the dehalogenation of tetrachloroethylene in D. tiedjei is catalyzed by a dehalogenase previously thought to be specific for meta-halobenzoates. PMID:16535377

Biodegradation of trichloroethylene and its anaerobic daughter products in freshwater wetland sediments

USGS Publications Warehouse

Lorah, M.M.; Olsen, L.D.

2001-01-01

Laboratory microcosms were prepared under methanogenic, sulfate-reducing, and aerobic conditions using sediment and groundwater from a freshwater wetland that is a discharge area for a trichloroethylene (TCE) to evaluate potential biodegradation rates of TCE and its anaerobic daughter products (cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, and vinyl chloride (VC)). Anaerobic degradation of TCE was about an order of magnitude faster under methanogenic conditions than under sulfate-reducing conditions. Both 12DCE and VC were found under sulfate-reducing conditions in the microcosms containing the wetland sediment, but their production, especially for VC, was substantially slower than under methanogenic conditions. Methane concentrations remained approximately constant (when losses in the formalin-amended controls are considered) in the microcosms amended with TCE and increased in the microcosms amended with the 12DCE isomers and VC during the first 18-25 days of incubation. The most rapid decrease in concentrations of TCE, cis-12DCE, trans-12DCE, and VC was found after aerobic methane-oxidizing conditions were definitely established.

Polyaryl ethers and related polysiloxane copolymer molecular coatings preparation and radiation degrdation

NASA Technical Reports Server (NTRS)

Mcgrath, J. E.; Hedrick, J. L.; Webster, D. C.; Johnson, B. C.; Mohanty, D. K.; Yilgor, I.

1983-01-01

Poly(arylene ether sulfones) comprise a class of materials known as engineering thermoplastics which have a variety of important applications. These polymers are tough, rigid materials with good mechanical properties over a wide temperature range, and they are processed by conventional methods into products typically having excellent hydrolytic, thermal, oxidative and dimensional stability. Wholly aromatic random copolymers of hydroquinone and biphenol with 4.4 prime dichlorodiphenyl sulfone were synthesized via mechanical nucleophilic displacement. Their structures were characterized and mechanical behavior studied. These tough, ductile copolymers show excellent radiation resistance to electron beam treatment and retain much of the mechanical properties up to at least 700 Mrads under argon.

Health assessment for Stanley Kessler, King of Prussia, Montgomery County, Pennsylvania, Region 3. CERCLIS No. PAD014269971. Preliminary report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1988-12-05

The Stanley Kessler site in King of Prussia, Pennsylvania, is a former metal recycling facility which operated from 1961 until 1978. Organic solvent-contaminated cooling water was disposed of in an underground septic tank and cesspool which has no structural bottom. Located nearby is a major source of drinking water for the Philadelphia Suburban Water Company which serves approximately 800,000 people. The environmental contamination consists of trichloroethylene, 1,1-dichloroethylene, and 1,1,1-trichloroethane in groundwater; 1,1,1-trichloroethane, 1,1-dichloroethylene, ethyl benzene, methylene chloride, tetrachloroethylene, toluene, and trichloroethylene in soil. The site appears to have been remediated with the exception of groundwater contamination. However, no data concerningmore » the effectiveness of the removal operations conducted in 1981 were provided. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via groundwater. This judgment is based on the absence of information concerning off-site contamination in soil and surface water, and the location, depth, and use of local private wells.« less

Verification of Methods for Assessing the Sustainability of Monitored Natural Attenuation (MNA)

DTIC Science & Technology

2013-01-01

surface CVOC chlorinated volatile organic compound DCE cis-1,2-Dichloroethylene DNAPL dense non-aqueous phase liquid DO dissolved oxygen DOC...considered detailed representations of aquifer heterogeneity, DNAPL distributions, and interfacial surface area. Thus, the upscaled SZD function considers...the effects of decreases in interfacial surface area with time as NAPL mass depletes, but not in an explicit manner. Likewise, the upscaled model is

Laboratory Evaluation of Drop-in Solvent Alternatives to n-Propyl Bromide for Vapor Degreasing

NASA Technical Reports Server (NTRS)

Mitchell, Mark A.; Lowrey, Nikki M.

2012-01-01

Based on this limited laboratory study, solvent blends of trans-1,2 dichloroethylene with HFEs, HFCs, or PFCs appear to be viable alternatives to n-propyl bromide for vapor degreasing. The lower boiling points of these blends may lead to greater solvent loss during use. Additional factors must be considered when selecting a solvent substitute, including stability over time, VOC, GWP, toxicity, and business considerations.

Odour Samples Degradation During Detention in Tedlar® Bags.

PubMed

Szyłak-Szydłowski, Mirosław

In indirect olfactometry analysis, to avoid condensation or adsorption processes during or storage of the sample, containers made of suitable materials should be used. Also, reaction between the chemicals during transport from the source of the odour to the research laboratory is an important process which can influence on examinations' results. Study included determination of the odour and compound concentrations of six gas mixtures. Gas samples were collected by silicone hoses into Tedlar ® bags and tested by Nasal Ranger, SM-100 olfactometers and Photovac Voyager gas chromatograph. Time of keeping gas in bags was 78 h, and concentration of compounds was measured every hour, eight times per day. For benzene, acetone, 1,1-dichloroethylene, c-1,2-dichloroethylene, t-1,2-dichloroethylene, methyl ethyl ketone and vinyl chloride, 100 % decrease of concentration has been noticed within 78 h of holding in the bag. Average rate of loss of most compounds concentration was from 0.01 to 2.50 % for the first 30 h and from 0.35 to 18.50 % during the last 48 h of examination. Decreasing of odour concentration measured by Nasal Ranger (NR) in all series was between 0.00 and 4.98 % till 30 h, between 1.91 and 100 % in the last 48 h of test and between 1.61 and 100 % in 78 h. In case of odour concentration measured by SM, those values were, respectively, 1.26-4.93 %, 1.39-4.93 % and 2.40-3.18 %. Values of average rate of intensity decreasing were, respectively, 0.77-1.75 %, 2.36-4.67 % and 1.18-2.07 %. Statistically significant correlation coefficients for compound concentrations and intensity, odour concentration obtained by SM-100 as well as NR were, respectively, 0.55-0.97, 0.47-0.99 and 0.37-0.98.

40 CFR 141.61 - Maximum contaminant levels for organic contaminants.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Polychlorinated biphenyls 0.0005 (16) 87-86-5 Pentachlorophenol 0.001 (17) 8001-35-2 Toxaphene 0.003 (18) 93-72-1...-Dichloroethylene 0.07 (10) 78-87-5 1,2-Dichloropropane 0.005 (11) 100-41-4 Ethylbenzene 0.7 (12) 108-90-7 Monochlorobenzene 0.1 (13) 95-50-1 o-Dichlorobenzene 0.6 (14) 100-42-5 Styrene 0.1 (15) 127-18-4 Tetrachloroethylene...

In Situ Biological Treatment Test at Kelly Air Force Base. Volume 3. Appendices.

DTIC Science & Technology

1987-07-01

175 B-12 Results of Groundwater Acidity Monitoring. . . . . . . . 176 B-13 Results of Groundwater Alkalinity Monitoring . . . . . . 177 B- 14 ...Oichloroethylene 499 Vinyl chloride 850 1.2-cis dichloroethylene Pam jupe Table A-I. Results of 5/23/85 Groundwater Sampling (Continued) 14 aqualab inc. 9909...Sample No. : 08/134621 Matrix: NATURAL WATER Parameter Result Units CC SPECIAL SCAN 1400 ug/L Client I.D.: 14 ERG Sample No.: 08/134622 Matrix

Organochlorine residues in odontocete species from the southeast coast of India.

PubMed

Karuppiah, S; Subramanian, A; Obbard, J P

2005-08-01

Blubber from bottle-nose dolphins, spinner dolphins, humpback dolphin (Tursiops truncatus, Stenella longirostris and Sousa chinensis) were collected from the Bay of Bengal (southeast coast of India) and analyzed for the organochlorine pesticides hexachlorocyclohexane (HCHs), p,p'-dichlorodiphenyl trichloroethane (DDTs), and polychlorinated biphenyls (PCBs). All nine specimens analyzed contained considerable levels of all the three chemical classes where DDT was in the range of 3330-23330 ng/g; HCHs in the range of 95-765 ng/g; and PCBs in the range of 210-1220 ng/g (wet weight basis). The reasons for this and the variations in the isomer pattern of HCHs and DDT and its metabolites in marine mammal tissues are discussed.

Synthesis and anthelmintic activity of 2,2'-disubstituted 5,5'-dibenzimidazolylsulfides and sulfones.

PubMed

Abuzar, S; Sharma, S; Visen, P K; Gupta, S; Katiyar, J C

1986-03-01

A number of substituted diphenylsulfides and sulfones (4-11) and 2,2'-disubstituted-5,5'-dibenzimidazolyl sulfides and sulphones (12-19) have been synthesized starting from 5-chloro-2-nitroacetanilide and (3) 4,4'-dichlorodiphenyl sulfone (9), respectively. Among the compounds tested against Ancylostoma ceylanicum in hamsters and Hymenolepis nana in rats and mice, 14, 15, 18 and 19 removed 100% of the worms at an oral dose of 25 mg/kg X 1 to 250 mg/kg X 3. Some of the compounds were tested for their blood schizontocidal activity against Plasmodium berghei in mice but none showed any activity up to an oral dose of 10 mg/kg given for 6 days.

Thermal electron attachment to chlorinated alkenes in the gas phase

NASA Astrophysics Data System (ADS)

Wnorowski, K.; Wnorowska, J.; Michalczuk, B.; Jówko, A.; Barszczewska, W.

2017-01-01

This paper reports the measurements of the rate coefficients and the activation energies of the electron capture processes with various chlorinated alkenes. The electron attachment processes in the mixtures of chlorinated alkenes with carbon dioxide have been investigated using a Pulsed Townsend technique. This study has been performed in the temperature range (298-378) K. The obtained rate coefficients more or less depended on temperature in accordance to Arrhenius equation. The activation energies (Ea's) were determined from the fit to the experimental data points with function ln(k) = ln(A) - Ea/kBT. The rate coefficients at 298 K were equal to 1.0 × 10-10 cm3 s-1, 2.2 × 10-11 cm3 s-1, 1.6 × 10-9 cm3 s-1, 4.4 × 10-8 cm3 s-1, 2.9 × 10-12 cm3 s-1 and 7.3 × 10-12 cm3 s-1 and activation energies were: 0.27 eV, 0.26 eV, 0.25 eV, 0.21 eV, 0.55 eV and 0.42 eV, for trans-1,2-dichloroethylene, cis-1,2-dichloroethylene, trichloroethylene, tetrachloroethylene, 2-chloropropene, 3-chloropropene respectively.

Use of On-Site GC/MS Analysis to Distinguish between Vapor Intrusion and Indoor Sources of VOC

DTIC Science & Technology

2013-12-01

TCE trichloroethylene trans-1,2-DCE trans-1,2-dichloroethylene USEPA U.S. Environmental Protection Agency UST underground storage tank VI vapor... trichloroethylene (TCE) VI; however, for this building, the CSIA result provided strong evidence of an indoor source. The scenario that best fits...concentrations of trichloroethylene (TCE) range from 0.3 to 1.6 micrograms per cubic meter (µg/m3) in houses unaffected by VI (50th to 95th percentile

Serum PCB and DDE levels of frequent Great Lakes sport fish consumers -- A first look

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hanrahan, L.P.; Falk, C.; Anderson, H.A.

1999-02-01

Great Lakes (GL) sport fish consumption is a potential human exposure route for polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethene (DDE). Because of fish tissue contamination, frequent consumers of Great Lakes sport caught fish (GLSCF) may be at risk for PCB and DDE accumulation. To examine this problem, the Health Departments of Wisconsin, Illinois, Indiana, Ohio, and Michigan formed a health assessment consortium. Participants were contacted by telephone to complete a detailed demographic and fish consumption survey. Frequent and infrequent GLSCF consumers were identified, and a participant subset was then asked to donate blood for PCB and DDE analysis. Analysis ofmore » variance (ANOVA) was done to study exposure group mean differences, while correlation and regression analyses were performed to examine relationships between demographic characteristics, GLSCF consumption, PCB, and DDE body burdens.« less

ABIOTIC NATURAL ATTENUATION OF CIS-DISHLOROETHYLENE AND 1,1-DICHLOROETHYLENE IN AQUIFER SEDIMENT

EPA Science Inventory

The disposal of TCE and 1,1,1-TCA at the Twin Cities Army Ammunition Plant (TCAAP) in Minnesota produced a plume of contaminated ground water that was over eight kilometers long. Although the size of the plume was consistent with a high ground water velocity in the aquifer and t...

Resonant inelastic x-ray scattering on iso-C{sub 2}H{sub 2}Cl{sub 2} around the chlorine K-edge: Structural and dynamical aspects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kawerk, Elie, E-mail: eliekawerk@hotmail.com, E-mail: ekawerk@units.it; Sorbonne Universités, UPMC Université Paris 06, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris; Laboratoire de Physique Appliquée, Faculté des Sciences II, Université Libanaise, 90656 Jdeidet el Metn, Liban

2014-10-14

We report a theoretical and experimental study of the high resolution resonant K{sub α} X-ray emission lines around the chlorine K-edge in gas phase 1,1-dichloroethylene. With the help of ab initio electronic structure calculations and cross section evaluation, we interpret the lowest lying peak in the X-ray absorption and emission spectra. The behavior of the K{sub α} emission lines with respect to frequency detuning highlights the existence of femtosecond nuclear dynamics on the dissociative Potential Energy Surface of the first K-shell core-excited state.

Resonant inelastic x-ray scattering on iso-C₂H₂Cl₂ around the chlorine K-edge: structural and dynamical aspects.

PubMed

Kawerk, Elie; Carniato, Stéphane; Journel, Loïc; Marchenko, Tatiana; Piancastelli, Maria Novella; Žitnik, Matjaž; Bučar, Klemen; Bohnic, Rok; Kavčič, Matjaž; Céolin, Denis; Khoury, Antonio; Simon, Marc

2014-10-14

We report a theoretical and experimental study of the high resolution resonant K(α) X-ray emission lines around the chlorine K-edge in gas phase 1,1-dichloroethylene. With the help of ab initio electronic structure calculations and cross section evaluation, we interpret the lowest lying peak in the X-ray absorption and emission spectra. The behavior of the K(α) emission lines with respect to frequency detuning highlights the existence of femtosecond nuclear dynamics on the dissociative Potential Energy Surface of the first K-shell core-excited state.

Resonant inelastic x-ray scattering on iso-C2H2Cl2 around the chlorine K-edge: Structural and dynamical aspects

NASA Astrophysics Data System (ADS)

Kawerk, Elie; Carniato, Stéphane; Journel, Loïc; Marchenko, Tatiana; Piancastelli, Maria Novella; Žitnik, Matjaž; Bučar, Klemen; Bohnic, Rok; Kavčič, Matjaž; Céolin, Denis; Khoury, Antonio; Simon, Marc

2014-10-01

We report a theoretical and experimental study of the high resolution resonant Kα X-ray emission lines around the chlorine K-edge in gas phase 1,1-dichloroethylene. With the help of ab initio electronic structure calculations and cross section evaluation, we interpret the lowest lying peak in the X-ray absorption and emission spectra. The behavior of the Kα emission lines with respect to frequency detuning highlights the existence of femtosecond nuclear dynamics on the dissociative Potential Energy Surface of the first K-shell core-excited state.

Biodegradation of individual and multiple chlorinated aliphatic hydrocarbons by methane-oxidizing cultures.

PubMed Central

Chang, H L; Alvarez-Cohen, L

1996-01-01

The microbial degradation of chlorinated and nonchlorinated methanes, ethanes, and ethanes by a mixed methane-oxidizing culture grown under chemostat and batch conditions is evaluated and compared with that by two pure methanotrophic strains: CAC1 (isolated from the mixed culture) and Methylosinus trichosporium OB3b. With the exception of 1,1-dichloroethylene, the transformation capacity (Tc) for each chlorinated aliphatic hydrocarbon was generally found to be in inverse proportion to its chlorine content within each aliphatic group (i.e., methanes, ethanes, and ethenes), whereas similar trends were not observed for degradation rate constants. Tc trends were similar for all methane-oxidizing cultures tested. None of the cultures were able to degrade the fully chlorinated aliphatics such as perchloroethylene and carbon tetrachloride. Of the four cultures tested, the chemostat-grown mixed culture exhibited the highest Tc for trichloroethylene, cis-1,2-dichloroethylene, tetrachloroethane, 1,1,1-trichloroethane, and 1,2-dichloroethane, whereas the pure batch-grown OB3b culture exhibited the highest Tc for all other compounds tested. The product toxicity of chlorinated aliphatic hydrocarbons in a mixture containing multiple compounds was cumulative and predictable when using parameters measured from the degradation of individual compounds. The Tc for each chlorinated aliphatic hydrocarbon in a mixture (Tcmix) and the total Tc for the mixture (sigma Tcmix) are functions of the individual Tc, the initial substrate concentration (S0), and the first-order rate constant (k/Ks) of each compound in the mixture, indicating the importance of identifying the properties and compositions of all potentially degradable compounds in a contaminant mixture. PMID:8795228

Effects of adrenolytic mitotane on drug elimination pathways assessed in vitro.

PubMed

Theile, Dirk; Haefeli, Walter Emil; Weiss, Johanna

2015-08-01

Mitotane (1,1-dichloro-2-(o-chlorophenyl)-2-(p-chlorophenyl)ethane, o,p'-DDD) represents one of the most active drugs for the treatment of adrenocortical carcinoma. Its metabolites 1,1-(o,p'-dichlorodiphenyl) acetic acid (=o,p'-DDA) and 1,1-(o,p'-dichlorodiphenyl)-2,2 dichloroethene (=o,p'-DDE) partly contribute to its pharmacological effects. Because mitotane has a narrow therapeutic index and causes pharmacokinetic drug-drug interactions, knowledge about these compounds' effects on drug metabolizing and transporting proteins is crucial. Using quantitative real-time polymerase chain reaction, our study confirmed the strong inducing effects of o,p'-DDD on mRNA expression of cytochrome P450 3A4 (CYP3A4, 30-fold) and demonstrated that other enzymes and transporters are also induced (e.g., CYP1A2, 8.4-fold; ABCG2 (encoding breast resistance cancer protein, BCRP), 4.2-fold; ABCB1 (encoding P-glycoprotein, P-gp) 3.4-fold). P-gp induction was confirmed at the protein level. o,p'-DDE revealed a similar induction profile, however, with less potency and o,p'-DDA had only minor effects. Reporter gene assays clearly confirmed o,p'-DDD to be a PXR activator and for the first time demonstrated that o,p'-DDE and o,p'-DDA also activate PXR albeit with lower potency. Using isolated, recombinant CYP enzymes, o,p'-DDD and o,p'-DDE were shown to strongly inhibit CYP2C19 (IC50 = 0.05 and 0.09 µM). o,p'-DDA exhibited only minor inhibitory effects. In addition, o,p'-DDD, o,p'-DDE, and o,p'-DDA are demonstrated to be neither substrates nor inhibitors of BCRP or P-gp function. In summary, o,p'-DDD and o,p'-DDE might be potential perpetrators in pharmacokinetic drug-drug interactions through induction of drug-metabolizing enzymes or drug transporters and by potent inhibition of CYP2C19. In tumors over-expressing BCRP or P-gp, o,p'-DDD and its metabolites should retain their efficacy due to a lack of substrate characteristics.

Health assessment for Watkins-Johnson Facility, Scotts Valley, California, Region 9. CERCLIS No. CAD980893234. Preliminary report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The Watkins-Johnson facility is on the National Priorities List. The facility manufactures electronic components. The environmental sampling conducted to date indicates that the contaminants of concern at the site are predominantly VOCs present in ground water, surface water, and soil. The VOCs present in one or more environmental media include trichloroethylene (TCE); 1,2-dichloroethylene (DCE); tetrachloroethylene perchloroethylene (PCE); vinyl chloride; methylene chloride; 1,1,1-trichloroethane (TCA); and Freon 113. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via ingestion of contaminated ground water.

Ionization Study of Isomeric Molecules in Strong-field Laser Pulses

DOE PAGES

Zigo, Stefan; Le, Anh-Thu; Timilsina, Pratap; ...

2017-02-10

Through the use of the technique of time-of-flight mass spectroscopy, we obtain strong-field ionization yields for randomly oriented 1,2-dichloroethylene (1,2-DCE) (C 2H 2Cl 2) and 2-butene (C 4H 8). Here, we are interested in studying the effect of conformal structure in strong-field ionization and, in particular, the role of molecular polarity. That is, we can perform strong-field ionization studies in polar vs non-polar molecules that have the same chemical composition. Here, we report our findings through the ionization yields and the ratio (trans/cis) of each stereoisomer pair as a function of intensity.

Monitoring of a wide range of organic micropollutants on the Portuguese coast using plastic resin pellets.

PubMed

Mizukawa, Kaoruko; Takada, Hideshige; Ito, Maki; Geok, Yeo Bee; Hosoda, Junki; Yamashita, Rei; Saha, Mahua; Suzuki, Satoru; Miguez, Carlos; Frias, João; Antunes, Joana Cepeda; Sobral, Paula; Santos, Isabelina; Micaelo, Cristina; Ferreira, Ana Maria

2013-05-15

We analyzed polychlorinated biphenyls (PCBs), dichlorodiphenyl dichloroethane and its metabolites, hexachlorocyclohexanes (HCHs), polycyclic aromatic hydrocarbons (PAHs), and hopanes, in plastic resin pellets collected from nine locations along the Portuguese coast. Concentrations of a sum of 13 PCBs were one order of magnitude higher in two major cities (Porto: 307 ng/g-pellet; Lisboa: 273 ng/g-pellet) than in the seven rural sites. Lower chlorinated congeners were more abundant in the rural sites than in the cities, suggesting atmospheric dispersion. At most of the locations, PAH concentrations (sum of 33 PAH species) were ∼100 to ∼300 ng/g-pellet; however, three orders of magnitude higher concentrations of PAHs, with a petrogenic signature, were detected at a small city (Sines). Hopanes were detected in the pellets at all locations. This study demonstrated that multiple sample locations, including locations in both urban and remote areas, are necessary for country-scale pellet watch. Copyright © 2013 Elsevier Ltd. All rights reserved.

Persistent Organic Pollutants in albacore tuna (Thunnus alalunga) from Reunion Island (Southwest Indian Ocean) and South Africa in relation to biological and trophic characteristics.

PubMed

Munschy, C; Bodin, N; Potier, M; Héas-Moisan, K; Pollono, C; Degroote, M; West, W; Hollanda, S J; Puech, A; Bourjea, J; Nikolic, N

2016-07-01

The contamination of albacore tuna (Thunnus alalunga) by Persistent Organic Pollutants (POPs), namely polychlorinated biphenyls (PCBs) and dichlorodiphenyl-trichloroethane (DDT), was investigated in individuals collected from Reunion Island (RI) and South Africa's (SA) southern coastlines in 2013, in relation to biological parameters and feeding ecology. The results showed lower PCB and DDT concentrations than those previously reported in various tuna species worldwide. A predominance of DDTs over PCBs was revealed, reflecting continuing inputs of DDT. Tuna collected from SA exhibited higher contamination levels than those from RI, related to higher dietary inputs and higher total lipid content. Greater variability in contamination levels and profiles was identified in tuna from RI, explained by a higher diversity of prey and more individualistic foraging behaviour. PCB and DDT contamination levels and profiles varied significantly in tuna from the two investigated areas, probably reflecting exposure to different sources of contamination. Copyright © 2016 Elsevier Inc. All rights reserved.

KINETICS OF VINYL RADICAL REACTIONS WITH ETHYLENE, TRANS-1,2-DICHLOROETHYLENE, AND TETRACHLOROETHYLENE. (R826167)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Food safety.

PubMed

Borchers, Andrea; Teuber, Suzanne S; Keen, Carl L; Gershwin, M Eric

2010-10-01

Food can never be entirely safe. Food safety is threatened by numerous pathogens that cause a variety of foodborne diseases, algal toxins that cause mostly acute disease, and fungal toxins that may be acutely toxic but may also have chronic sequelae, such as teratogenic, immunotoxic, nephrotoxic, and estrogenic effects. Perhaps more worrisome, the industrial activities of the last century and more have resulted in massive increases in our exposure to toxic metals such as lead, cadmium, mercury, and arsenic, which now are present in the entire food chain and exhibit various toxicities. Industrial processes also released chemicals that, although banned a long time ago, persist in the environment and contaminate our food. These include organochlorine compounds, such as 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (dichlorodiphenyl dichloroethene) (DDT), other pesticides, dioxins, and dioxin-like compounds. DDT and its breakdown product dichlorophenyl dichloroethylene affect the developing male and female reproductive organs. In addition, there is increasing evidence that they exhibit neurodevelopmental toxicities in human infants and children. They share this characteristic with the dioxins and dioxin-like compounds. Other food contaminants can arise from the treatment of animals with veterinary drugs or the spraying of food crops, which may leave residues. Among the pesticides applied to food crops, the organophosphates have been the focus of much regulatory attention because there is growing evidence that they, too, affect the developing brain. Numerous chemical contaminants are formed during the processing and cooking of foods. Many of them are known or suspected carcinogens. Other food contaminants leach from the packaging or storage containers. Examples that have garnered increasing attention in recent years are phthalates, which have been shown to induce malformations in the male reproductive system in laboratory animals, and bisphenol A, which negatively

Reactivities of Precision Cleaning Solvents with Hypergolic Propellants

NASA Technical Reports Server (NTRS)

Davis, Dennis D.; Delgado, Rafael H.; Williams, James H.

1999-01-01

The reactivities of several selected halogenated precision cleaning solvents with hypergolic propellants has been determined by analysis of the rates of formation of halide ion decomposition products. The solvents were Asahiklin AK 225, Asahiklin AK 225 AES, HFE 7100, HFE 7100 DE, Vertrel XF, Vertrel MCA, Vertrel MCA Plus, 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113), and trans-1,2-dichloroethylene (DCE). The propellants were hydrazine (HZ), monomethylhydrazine (MMH), and mixed oxides of nitrogen (MON-3). The Vertrel solvents showed significant reactivity with HZ. All of the solvents except DCE exhibited significant reactivity with MMH, particularly HFE 7100 DE and CFC-113. HFE 7100 DE, Vertrel MCA, and Vertrel MCA Plus also showed significant reactivity with MON-3 oxidizer.

Online analysis of chlorine stable isotopes in chlorinated ethylenes: an inter-laboratory study

NASA Astrophysics Data System (ADS)

Bernstein, Anat; Shouakar-Stash, Orfan; Hunkeler, Daniel; Sakaguchi-Söder, Kaori; Laskov, Christine; Aravena, Ramon; Elsner, Martin

2010-05-01

In the last decade, compound-specific stable isotopes analysis of groundwater pollutants became an important tool to identify different sources of the same pollutant and for tracking natural attenuating processes in the sub-surface. It has been shown that trends in the isotopic composition of the target compounds can shed light on in-situ processes that are otherwise difficult to track. Analytical methods of carbon, nitrogen and hydrogen were established and are by now frequently used for a variety of organic pollutants. Yet, the motivation of introducing analytical methods for new isotopes is emerging. This motivation is further enhanced, as advantages of using two or more stable isotopes for gaining better insight on degradation pathways are well accepted. One important element which demands the development of appropriate analytical methods is chlorine, which is found in various groups of organic pollutants, among them the chlorinated ethylenes. Chlorinated ethylenes are considered as high priority environmental pollutants, and the development of suitable chlorine isotope methods for this group of pollutants is highly desired. Ideally, stable isotope techniques should have the capability to determine the isotopic composition of and individual target compound in a non-pure mixture, without the requirement of a laborious off-line treatment. Indeed, in the last years two different concepts for on-line chlorine isotope analysis methods were introduced, by using either a standard quadrapole GC/MS (Sakaguchi-Söder et al., 2007) or by using a GC/IRMS (Shouakar-Stash et al., 2006). We present a comparison of the performances of two concepts, carried out in five different laboratories: Waterloo (GC/IRMS), Neuchâtel (GC/MS), Darmstadt (GC/MS), Tübingen (GC/MS) and Munich (GC/IRMS). This comparison was performed on pure trichloroethylene and dichloroethylene products of different manufactures, as well as trichloroethylene and dichloroethylene samples that were exposed to

The potentiality of botanicals and their products as an alternative to chemical insecticides to sandflies (Diptera: Psychodidae): a review.

PubMed

Dinesh, Diwakar Singh; Kumari, Seema; Kumar, Vijay; Das, Pradeep

2014-03-01

Use of chemical pesticides is the current method for controlling sandflies. However, resistance is being developed in sandflies against the insecticide of choice that is DDT (dichlorodiphenyl trichloroethane). Botanicals have potential to act as an alternative to chemical insecticides as the crude extracts and active molecules of some plants show insecticidal effect to sandflies. This will lead to safe, easy and environment friendly method for control of sandflies. Therefore, information regarding botanicals acting as alternative to chemical insecticide against sandflies assumes importance in the context of development of resistance to insecticides as well as to prevent environment from contamination. This review deals with some plants and their products having repellent and insecticidal effect to sandflies in India and abroad. Different methods of extraction and their bioassay on sandflies have been emphasized in the text. Various extracts of some plants like Ricinus communis (Euphorbiaceae), Solanum jasminoides (Solanaceae), Bougainvillea glabra (Nyctaginaceae), Capparis spinosa (Capparidaceae), Acalypha fruticosa (Euphorbiaceae) and Tagetes minuta (Asteraceae) had shown repellent/insecticidal effect on sandflies. This review will be useful in conducting the research work to find out botanicals of Indian context having insecticidal effect on sandflies.

POST-REMEDIATION BIOMONITORING OF PESTICIDES AND OTHER CONTAMINANTS IN MARINE WATERS AND SEDIMENT NEAR THE UNITED HECKATHORN SUPERFUND SITE, RICHMOND, CALIFORNIA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Antrim, Liam D.; Kohn, Nancy P.

Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in February 1999 from four stations near Lauritzen Canal in Richmond, California, for Year 2 of post-remediation monitoring of marine areas near the United Heckathorn Site. Dieldrin and dichlorodiphenyl trichloroethane (DDT) were analyzed in water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Mussel tissues were also analyzed for polychlorinated biphenyls (PCB), which were detected in sediment samples. Chlorinated pesticide concentrations in water samples were similar to preremediation levels and did notmore » meet remediation goals. Biomonitoring results indicated that the bioavailability of chlorinated pesticides has been reduced from preremediation levels both in the dredged area and throughout Richmond Harbor. Total DDT and dieldrin concentrations in mussel tissues were lower than measured levels from preremediation surveys and also lower than Year 1 levels from post-remediation biomonitoring. Sediment analyses showed the presence of elevated DDT, dieldrin, PCB aroclor 1254, and very high levels of polynuclear aromatic hydrocarbons (PAH) in Lauritzen Channel.« less

Human tissue burdens of halogenated aromatic chemicals in Michigan.

PubMed

Wolff, M S; Anderson, H A; Selikoff, I J

1982-04-16

A cross section of the population of Michigan was studied in 1978 to evaluate residual burdens of polybrominated biphenyls (PBBs), a flame-retardant chemical that had contaminated the state's food supply five years earlier. Levels of PBB were measured in serum specimens in 1,681 people and in adipose samples in 844. Ninety-seven percent of the adipose samples had detectable PBB concentrations. Levels of PBB were highest in that part of the state where meat and dairy products had been most contaminated and were lowest in the upper peninsula, farthest from the source. Levels for the rest of the state were in between. Polychlorinated biphenyls (PCB) and 2,2'-bis(p-chlorophenyl)-1, 1-dichloroethylene (p,p'-DDE), a dichlorodiphenyltrichloroethane (DDT) residue, were also measured, and variations of PBB, PCB, and p,p'-DDE levels with age and sex were investigated.

Alternative Green Solvents Project

NASA Technical Reports Server (NTRS)

Maloney, Phillip R.

2012-01-01

Necessary for safe and proper functioning of equipment. Mainly halogenated solvents. Tetrachloride, Trichloroethylene (TCE), CFC-113. No longer used due to regulatory/safety concerns. Precision Cleaning at KSC: Small % of total parts. Used for liquid oxygen (LOX) systems. Dual solvent process. Vertrel MCA (decafluoropentane (DFP) and trons-dichloroethylene) HFE-7100. DFP has long term environmental concerns. Project Goals: a) Identify potential replacements. b) 22 wet chemical processes. c) 3 alternative processes. d) Develop test procedures. e) Contamination and cleaning. f) Analysis. g) Use results to recommend alternative processes. Conclusions: a) No alternative matched Vertrel in this study. b) No clear second place solvent. c) Hydrocarbons- easy; Fluorinated greases- difficult. d) Fluorinated component may be needed in replacement solvent. e) Process may need to make up for shortcoming of the solvent. f) Plasma and SCC02 warrant further testing.

Formalin preservation of avian blood for organochlorine analysis

USGS Publications Warehouse

Stafford, C.J.; Stickel, W.H.; Lamb, D.W.; Kenaga, E.E.

1981-01-01

Blood biopsy for chemical analysis is a valuable technique for evaluating chemical exposure of birds in the wild without harming the birds. Field conditions, however, often make sample storage difficult. Better methods than freezing are needed to improve the interpretive value of chemical analysis of the sample. The use of formalin was explored for this purpose. A pooled sample of blood containing naturally incorporated 1,1-bis-(p-chlorophenyl)-2,2,2-trichloroethane (DDT), 2,2-bis-(p-chlorophenyl)1,1 dichloroethylene (DDE), and dieldrin was subdivided into 30 samples, of which 10 were frozen, 10 more were kept at room temperature, and 10 were formalinized by adding I part of chemically pure formalin to 20 parts of blood. The formalinized samples yielded the highest and least variable concentrations of chemicals. The field procedures are outlined.

Inorganic and organic ground-water chemistry in the Canal Creek area of Aberdeen Proving Ground, Maryland

USGS Publications Warehouse

Lorah, M.M.; Vroblesky, D.A.

1989-01-01

Groundwater chemical data were collected from November 1986 through April 1987 in the first phase of a 5-year study to assess the possibility of groundwater contamination in the Canal Creek area of Aberdeen Proving Ground, Maryland. Water samples were collected from 87 observation wells screened in Coastal Plain sediments; 59 samples were collected from the Canal Creek aquifer, 18 from the overlying surficial aquifer, and 10 from the lower confined aquifer. Dissolved solids, chloride, iron, manganese, fluoride, mercury, and chromium are present in concentrations that exceed the Federal maximum contaminant levels for drinking water. Elevated chloride and dissolved-solids concentrations appear to be related from contaminant plumes but also could result from brackish-water intrusion. Excessive concentrations of iron and manganese were the most extensive water quality problems found among the inorganic constituents and are derived from natural dissolution of minerals and oxide coatings in the aquifer sediments. Volatile organic compounds are present in the Canal Creek and surficial aquifers, but samples from the lower confined aquifer do not show any evidence of contamination by inorganic or organic chemicals. The volatile organic contaminants detected in the groundwater and their maximum concentrations (in micrograms/L) include 1,1,2,2- tetrachloroethane (9,000); carbon tetrachloride (480); chloroform (460); 1,1,2-trichloroethane (80); 1,2-dichloroethane (990); 1,1-dichloroethane (3.1); tetrachloroethylene (100); trichloroethylene (1,800); 1,2-trans- dichloroethylene (1,200); 1,1-dichloroethylene (4.4); vinyl chloride (140); benzene (70); and chlorobenzene (39). On the basis of information on past activities in the study area, some sources of the volatile organic compounds include: (1) decontaminants and degreasers; (2) clothing-impregnating operations; (3) the manufacture of impregnite material; (4) the manufacture of tear gas; and (5) fuels used in garages and at

An evaluation of microbial and chemical contamination sources related to the deterioration of tap water quality in the household water supply system.

PubMed

Lee, Yoonjin

2013-09-06

The predominant microorganisms in samples taken from shower heads in residences in the Korean city "N" were Stenotrophomonas maltophilia, Sphingomonas paucimobilis, Acidovorax temperans, and Microbacterium lacticum. Legionella was not detected in this case. The volatile organic compounds (VOCs) vinylacetate, NN-DMA, cis-1,2-dichloroethylene, epichlorohydrin, and styrene were measured in five types of plastic pipes: PVC, PB, PP, PE, and cPVC. The rate of multiplication of the heterotrophic plate count (HPC) attached on the copper pipe in contact with hot tap water was higher than the rate for the copper pipe in contact with cold tap water. Biofilm accumulation on stainless steel pipes with added acetate (3 mg/L) was 2.56 times higher than the non-supplemented condition. Therefore, the growth of HPC in the pipe system was affected by the type and availability of nutrients and depended on variables such as heating during the hot water supply.

Characterization of a microbial consortium capable of rapid and simultaneous dechlorination of 1,1,2,2-tetrachloroethane and chlorinated ethane and ethene intermediates

USGS Publications Warehouse

Jones, E.J.P.; Voytek, M.A.; Lorah, M.M.; Kirshtein, J.D.

2006-01-01

A study was carried out to develop a culture of microorganisms for bioaugmentation treatment of chlorinated-ethane contaminated groundwater at sites where dechlorination is incomplete or rates are too slow for effective remedation. Mixed cultures capable of dechlorinating chlorinated ethanes and ethenes were enriched from contaminated wetland sediment at Aberdeen Proving Ground (APG) Maryland. The West Branch Consortium (WBC-2) was capable of degrading 1,1,2,2-tetrachloroethane (TeCA), trichloroethylene (TCE), cis and trans 1,2-dichloroethylene (DCE), 1,1,2-trichloroethane (TCA), 1,2-dichloroethane, and vinyl chloride to nonchlorinated end products ethylene and ethane. WBC-2 dechlorinated TeCA, TCA, and cisDCE rapidly and simultaneously. Methanogens in the consortium were members of the class Methanomicrobia, which includes acetoclastic methanogens. The WBC-2 consortium provides opportunities for the in situ bioremediation of sites contaminated with mixtures of chlorinated ethylenes and ethanes.

Stable carbon isotope fractionation of chlorinated ethenes by a microbial consortium containing multiple dechlorinating genes.

PubMed

Liu, Na; Ding, Longzhen; Li, Haijun; Zhang, Pengpeng; Zheng, Jixing; Weng, Chih-Huang

2018-08-01

The study aimed to determine the possible contribution of specific growth conditions and community structures to variable carbon enrichment factors (Ɛ- carbon ) values for the degradation of chlorinated ethenes (CEs) by a bacterial consortium with multiple dechlorinating genes. Ɛ- carbon values for trichloroethylene, cis-1,2-dichloroethylene, and vinyl chloride were -7.24% ± 0.59%, -14.6% ± 1.71%, and -21.1% ± 1.14%, respectively, during their degradation by a microbial consortium containing multiple dechlorinating genes including tceA and vcrA. The Ɛ- carbon values of all CEs were not greatly affected by changes in growth conditions and community structures, which directly or indirectly affected reductive dechlorination of CEs by this consortium. Stability analysis provided evidence that the presence of multiple dechlorinating genes within a microbial consortium had little effect on carbon isotope fractionation, as long as the genes have definite, non-overlapping functions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Detection of banned meat and bone meal in feedstuffs by near-infrared microscopic analysis of the dense sediment fraction.

PubMed

Baeten, Vincent; von Holst, Christoph; Garrido, Ana; Vancutsem, Jeroen; Michotte Renier, Antoine; Dardenne, Pierre

2005-05-01

In this paper we present an alternative method for detection of meat and bone meal (MBM) in feedstuffs by near-infrared microscopic (NIRM) analysis of the particles in the sediment fraction (dense fraction (d >1.62) from dichloroethylene) of compound feeds. To apply this method the particles of the sediment fraction are spread on a sample holder and presented to the NIR microscope. By using the pointer of the microscope the infrared beam is focussed on each particle and the NIR spectrum (1112-2500 nm) is collected. This method can be used to detect the presence of MBM at concentrations as low as 0.05% mass fraction. When results from the NIRM method were compared with the classical microscopic method, a coefficient of determination (R2) of 0.87 was obtained. The results of this study demonstrated that this method could be proposed as a complementary tool for the detection of banned MBM in feedstuffs by reinforcement of the monitoring of feeds.

An Evaluation of Microbial and Chemical Contamination Sources Related to the Deterioration of Tap Water Quality in the Household Water Supply System

PubMed Central

Lee, Yoonjin

2013-01-01

The predominant microorganisms in samples taken from shower heads in residences in the Korean city “N” were Stenotrophomonas maltophilia, Sphingomonas paucimobilis, Acidovorax temperans, and Microbacterium lacticum. Legionella was not detected in this case. The volatile organic compounds (VOCs) vinylacetate, NN-DMA, cis-1,2-dichloroethylene, epichlorohydrin, and styrene were measured in five types of plastic pipes: PVC, PB, PP, PE, and cPVC. The rate of multiplication of the heterotrophic plate count (HPC) attached on the copper pipe in contact with hot tap water was higher than the rate for the copper pipe in contact with cold tap water. Biofilm accumulation on stainless steel pipes with added acetate (3 mg/L) was 2.56 times higher than the non-supplemented condition. Therefore, the growth of HPC in the pipe system was affected by the type and availability of nutrients and depended on variables such as heating during the hot water supply. PMID:24018837

Natural attenuation of chlorinated hydrocarbons in a freshwater wetland

USGS Publications Warehouse

Lora, Michelle M.; Olsen, Lisa D.; Smith, Barrett L.; Alleman, Bruce C.; Leeson, Andrea

1997-01-01

Natural attenuation of chlorinated volatile organic compounds (VOC's) occurs as ground water discharges from a sand aquifer to a freshwater wetland at Aberdeen Proving Ground, Md. Field and laboratory results indicate that biotransformation in the anaerobic wetland sediments is an important attenuation process. Relatively high concentrations of the parent compounds trichloroethylene (TCE) and 1,1,2,2-tetrachloroethane (PCA) and low or undetectable concentrations of daughter products were measured in the aquifer. In contrast, relatively high concentrations of the daughter products cis- and trans-1,2-dichloroethylene (12DCE); vinyl chloride (VC); 1,1,2-trichloroethane (112TCA); and 1,2-dichloroethane (12DCA) were measured in ground water in the wetland sediments, although total VOC concentrations decreased upward from about 1 mu mol/L (micromoles per liter) at the base of the wetland sediments to less than 0.2 near the surface. Microcosm experiments showed that 12DCE and VC are produced from anaerobic degradation of both TCE and PCA; PCA degradation also produced 112TCA and 12DCA.

Transformation of mackinawite to greigite by trichloroethylene and tetrachloroethylene.

PubMed

Lan, Ying; Elwood Madden, Andrew S; Butler, Elizabeth C

2016-10-12

Trichloroethylene (TCE) and tetrachloroethylene (PCE) are common ground water contaminants susceptible to reductive dechlorination by FeS (mackinawite) in anaerobic environments. The objective of this study was to characterize the mineral-associated products that form when mackinawite reacts with TCE and PCE. The dissolved products of the reaction included Cl - and Fe 2+ , and trace amounts of cis 1,2-dichloroethylene (for TCE) and TCE (for PCE). Selected area electron diffraction (SAED) analysis identified greigite as a mackinawite oxidation product formed after reaction between TCE or PCE and FeS over seven weeks. Release of Fe 2+ is consistent with the solid state transformation of mackinawite to greigite, resulting in depletion of the solid with Fe. X-ray photoelectron spectroscopy of the sulfur 2p peak showed a shift to a higher binding energy after FeS reacted with TCE or PCE, also observed in other studies of mackinawite oxidation to greigite. The results may help efforts to maintain the reactivity of FeS generated to remediate chlorinated aliphatic contaminants in ground water.

Numerical simulation of transport and sequential biodegradation of chlorinated aliphatic hydrocarbons using CHAIN_2D

NASA Astrophysics Data System (ADS)

Schaerlaekens, J.; Mallants, D.; Imûnek, J.; van Genuchten, M. Th.; Feyen, J.

1999-12-01

Microbiological degradation of perchloroethylene (PCE) under anaerobic conditions follows a series of chain reactions, in which, sequentially, trichloroethylene (TCE), cis-dichloroethylene (c-DCE), vinylchloride (VC) and ethene are generated. First-order degradation rate constants, partitioning coefficients and mass exchange rates for PCE, TCE, c-DCE and VC were compiled from the literature. The parameters were used in a case study of pump-and-treat remediation of a PCE-contaminated site near Tilburg, The Netherlands. Transport, non-equilibrium sorption and biodegradation chain processes at the site were simulated using the CHAIN_2D code without further calibration. The modelled PCE compared reasonably well with observed PCE concentrations in the pumped water. We also performed a scenario analysis by applying several increased reductive dechlorination rates, reflecting different degradation conditions (e.g. addition of yeast extract and citrate). The scenario analysis predicted considerably higher concentrations of the degradation products as a result of enhanced reductive dechlorination of PCE. The predicted levels of the very toxic compound VC were now an order of magnitude above the maximum permissible concentration levels.

Integrated Geophysical Investigation of Preferential Flow Paths at the Former Tyson Valley Powder Farm near Eureka, Missouri, May 2006

USGS Publications Warehouse

Burton, Bethany L.; Ball, Lyndsay B.; Stanton, Gregory P.; Hobza, Christopher M.

2009-01-01

In May 2006, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, conducted surface and borehole geophysical surveys at the former Tyson Valley Powder Farm near Eureka, Mo., to identify preferential pathways for potential contaminant transport along the bedrock surface and into dissolution-enhanced fractures. The Tyson Valley Powder Farm was formerly used as a munitions storage and disposal facility in the 1940s and 1950s, and the site at which the surveys were performed was a disposal area for munitions and waste solvents such as trichloroethylene and dichloroethylene. Direct-current resistivity and seismic refraction data were acquired on the surface; gamma, electromagnetic induction, and full waveform sonic logs were acquired in accessible boreholes. Through the combined interpretation of the seismic refraction tomographic and resistivity inversion results and borehole logs, inconsistencies in the bedrock surface were identified that may provide horizontal preferential flow paths for dense nonaqueous phase liquid contaminants. These results, interpreted and displayed in georeferenced three-dimensional space, should help to establish more effective monitoring and remediation strategies.

Effect of toluene concentration and hydrogen peroxide on Pseudomonas plecoglossicida cometabolizing mixture of cis-DCE and TCE in soil slurry.

PubMed

Li, Junhui; Lu, Qihong; de Toledo, Renata Alves; Lu, Ying; Shim, Hojae

2015-12-01

An indigenous Pseudomonas sp., isolated from the regional contaminated soil and identified as P. plecoglossicida, was evaluated for its aerobic cometabolic removal of cis-1,2-dichloroethylene (cis-DCE) and trichloroethylene (TCE) using toluene as growth substrate in a laboratory-scale soil slurry. The aerobic simultaneous bioremoval of the cis-DCE/TCE/toluene mixture was studied under different conditions. Results showed that an increase in toluene concentration level from 300 to 900 mg/kg prolonged the lag phase for the bacterial growth, while the bioremoval extent for cis-DCE, TCE, and toluene declined as the initial toluene concentration increased. In addition, the cometabolic bioremoval of cis-DCE and TCE was inhibited by the presence of hydrogen peroxide as the additional oxygen source, while the bioremoval of toluene (900 mg/kg) was enhanced after 9 days of incubation. The subsequent addition of toluene did not improve the cometabolic bioremoval of cis-DCE and TCE. The obtained results would help to enhance the applicability of bioremediation technology to the mixed waste contaminated sites.

Electron donor preference of a reductive dechlorinating consortium

USGS Publications Warehouse

Lorah, M.M.; Majcher, E.; Jones, E.; Driedger, G.; Dworatzek, S.; Graves, D.

2005-01-01

A wetland sediment-derived microbial consortium was developed by the USGS and propagated in vitro to large quantities by SiREM Laboratory for use in bioaugmentation applications. The consortium had the capacity to completely dechlorinate 1,1,2,2-tetrachloroethene, tetrachloroethylene, trichloroethylene, 1,1,2-trichloroethane, cis- and trans-1,2-dichoroethylene, 1.1-dichloroethylene, 1,2-dichloroethane, vinyl chloride, carbon tetrachloride and chloroform. A suite of electron donors with characteristics useful for bioaugmentation applications was tested. The electron donors included lactate (the donor used during WBC-2 development), ethanol, chitin (Chitorem???), hydrogen releasing compound (HRC???), emulsified vegetable oil (Newman Zone???), and hydrogen gas. Ethanol, lactate, and chitin were particularly effective with respect to stimulating, supporting, and sustaining reductive dechlorination of the broad suite of chemicals that WBC-2 biodegraded. Chitorem??? was the most effective "slow release" electron donor tested. This is an abstract of a paper presented at the Proceedings of the 8th International In Situ and On-Site Bioremediation Symposium (Baltimore, MD 6/6-9/2005).

Surface acoustic wave sensors/gas chromatography; and Low quality natural gas sulfur removal and recovery CNG Claus sulfur recovery process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klint, B.W.; Dale, P.R.; Stephenson, C.

This topical report consists of the two titled projects. Surface Acoustic Wave/Gas Chromatography (SAW/GC) provides a cost-effective system for collecting real-time field screening data for characterization of vapor streams contaminated with volatile organic compounds (VOCs). The Model 4100 can be used in a field screening mode to produce chromatograms in 10 seconds. This capability will allow a project manager to make immediate decisions and to avoid the long delays and high costs associated with analysis by off-site analytical laboratories. The Model 4100 is currently under evaluation by the California Environmental Protection Agency Technology Certification Program. Initial certification focuses upon themore » following organics: cis-dichloroethylene, chloroform, carbon tetrachloride, trichlorethylene, tetrachloroethylene, tetrachloroethane, benzene, ethylbenzene, toluene, and o-xylene. In the second study the CNG Claus process is being evaluated for conversion and recovery of elemental sulfur from hydrogen sulfide, especially found in low quality natural gas. This report describes the design, construction and operation of a pilot scale plant built to demonstrate the technical feasibility of the integrated CNG Claus process.« less

Differential effects of p,p'-DDE on testis and liver mitochondria: implications for reproductive toxicology.

PubMed

Mota, Paula C; Cordeiro, Marília; Pereira, Susana P; Oliveira, Paulo J; Moreno, António J; Ramalho-Santos, João

2011-01-01

The release of environmental contaminants can contribute to impaired male fertility. The bioenergetics of isolated liver mitochondria have been used as a toxicological indicator, an inexpensive first line model to screen possible effects of several substances. Here we report the effects of 2,2-bis(4-chlorophenyl)-1,1-dichloro-ethylene (DDE) on the bioenergetical parameters of testicular mitochondria. A significant decrease in repolarization potential (after a phosphorylative cycle), state 3 respiration and uncoupled respiration, with a concomitant increase in lag phase was found, demonstrating a decrease in mitochondrial function. Importantly, there was also a clear increase in maximum potential in DDE-treated testis mitochondria, which was not mirrored by more commonly used liver mitochondria. Indeed, comparative studies showed that testis and liver mitochondria have strikingly different sensitivities and patterns of response to DDE, indicating that testis mitochondria should be used as a primary toxicological model for a proper evaluation of putative effects of environmental toxicants on the bioenergetics of spermatogenesis and male fertility. Copyright © 2010 Elsevier Inc. All rights reserved.

Assessment of ground-water contamination at Wurtsmith Air Force Base, Michigan, 1982-85

USGS Publications Warehouse

Cummings, T.R.; Twenter, F.R.

1986-01-01

Continued study of ground-water contamination at Wurtsmith Air Force Base, Michigan, defined the movement and distribution of volatile organic compounds in the glacial sand and gravel aquifer at known sites of contamination, and has defined new plumes at two other sites. The Arrow Street purge system, installed in 1982 to remove contaminants from the Building 43 plume, has lowered concentrations of trichloroethylene in ground water in the central part of the most contaminated area from a range of 1,000 to 2,000 micrograms per liter to about 200 micrograms per liter. Trichloroethylene is not escaping off-Base from this area. In the southern part of the Base a plume containing principally trichloroethylene and dichloroethylene has been delineated along Mission Drive. Maximum concentrations observed were 5,290 micrograms per liter of trichloroethylene and 1,480 micrograms per liter of dichloroethylene. Hydrologically suitable sites for purge wells are identified in the southern part of the plume using a new ground-water flow model of the Base. A benzene plume near the bulk-fuel storage area, delineated in earlier work, lias shifted to a more northerly direction under influence of the Arrow Street purge system. Sites initially identified for purging the benzene plume have been repositioned because of the change in contaminant movement. JP-4 fuel was found to be accumulating in wells near the bulk-fuel storage area, largely in response to seasonal fluctuations in the water table. It is thought to originate from a spill that occurred several years ago. A more thorough definition of contaminants in the northern landfill area has permitted a determination of the most hydrologically suitable sites for purge wells. In general, Concentrations found in water do not differ greatly from those observed in 1981. Since 1981, concentrations of trichloroethylene have decreased significantly in the Alert Apron plume. Near the origin of the plume, the concentration of trichloroethylene

Insecticide resistance in bedbugs in Thailand and laboratory evaluation of insecticides for the control of Cimex hemipterus and Cimex lectularius (Hemiptera: Cimicidae).

PubMed

Tawatsin, Apiwat; Thavara, Usavadee; Chompoosri, Jakkrawarn; Phusup, Yutthana; Jonjang, Nisarat; Khumsawads, Chayada; Bhakdeenuan, Payu; Sawanpanyalert, Pathom; Asavadachanukorn, Preecha; Mulla, Mir S; Siriyasatien, Padet; Debboun, Mustapha

2011-09-01

Bedbugs are found in many countries around the world, and in some regions they are resistant to numerous insecticides. This study surveyed bedbugs in Thailand and determined their resistance to insecticides. The surveys were carried out in six provinces that attract large numbers of foreign tourists: Bangkok, Chonburi, Chiang Mai, Ubon Ratchathani, Phuket, and Krabi. Bedbugs were collected from hotels and colonized in the laboratory to evaluate their resistance to insecticides. Cimex hemipterus (F.) was found in some hotels in Bangkok, Chonburi, Phuket, and Krabi, whereas Cimex lectularius L. was found only in hotels in Chiang Mai. No bedbugs were found in Ubon Ratchathani. The colonized bedbugs showed resistance to groups of insecticides, including organochlorines (dichlorodiphenyl trichloroethane, dieldrin), carbamates (bendiocarb, propoxur), organophosphates (malathion, fenitrothion), and pyrethroids (cyfluthrin, deltamethrin, permethrin, lambda-cyhalothrin, etofenprox) in tests using World Health Organization insecticide-impregnated papers. The new insecticides imidacloprid (neonicotinoid group), chlorfenapyr (pyrrole group), and fipronil (phenylpyrazole group) were effective against the bedbugs; however, organophosphate (diazinon), carbamates (fenobucarb, propoxur), and pyrethroids (bifenthrin, cypermethrin, esfenvalerate, etofenprox) were ineffective. Aerosols containing various pyrethroid insecticides with two to four different active ingredients were effective against the bedbugs. The results obtained from this study suggested that both species of bedbugs in Thailand have developed marked resistance to various groups of insecticides, especially those in the pyrethroid group, which are the most common insecticides used for pest control. Therefore, an integrated pest management should be implemented for managing bedbugs in Thailand.

Sport fish consumption and body burden levels of chlorinated hydrocarbons: a study of Wisconsin anglers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fiore, B.J.; Anderson, H.A.; Hanrahan, L.P.

1989-03-01

Sport-caught fish consumption is the major source of polychlorinated biphenyls (PCBs) exposure for the general population. To assess this and 2,2'-bis-(p-chlorophenyl)-1,1-dichloroethylene (DDE) exposure, we surveyed 801 Wisconsin anglers for fishing and consumption habits and comprehension of and compliance with the Wisconsin fish consumption health advisory. The mean annual number of sport-caught fish meals was 18. Seventy-two percent of anglers were familiar with the health advisory and 57% had changed their fishing or fish consumption habits as a result of the advisory. The mean PCB serum congener sum level for 192 anglers was 2.2 micrograms/l (range = nondetectable to 27.1 micrograms/l);more » mean DDE was 6.3 micrograms/l (range = nondetectable to 40.0 micrograms/l). Statistically significant positive Spearman correlations were observed between sport-caught fish meals and PCB and DDE sera levels (R = .21 and .14, respectively) and between kilograms of fish caught and PCB sera levels (R = .25). These results demonstrate that anglers may provide a population for assessment of PCBs and DDE associated morbidity and mortality.« less

Anaerobic Transformation of Chlorinated Aliphatic Hydrocarbons in a Sand Aquifer Based on Spatial Chemical Distributions

NASA Astrophysics Data System (ADS)

Semprini, Lewis; Kitanidis, Peter K.; Kampbell, Don H.; Wilson, John T.

1995-04-01

We estimated the distribution of chlorinated aliphatic hydrocarbons (CAHs) from groundwater samples collected along three transects in a sand aquifer. Trichloroethylene (TCE) leaked and contaminated the aquifer probably more than a decade before we collected the measurements. The data show significant concentrations of TCE, cis-l,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethene. We attributed DCE, VC, and ethene to the reductive dehalogenation of TCE. The CAH concentrations varied significantly with depth and correlate with sulfate and methane concentrations. Anoxic aquifer conditions exist with methane present at relatively high concentrations at depth. High concentrations of TCE correspond with the absence of methane or low methane concentrations, whereas products of TCE dehalogenation are associated with higher methane concentrations and low sulfate concentrations. Indications are that the dechlorination of TCE and DCE to VC and ethene is associated with sulfate reduction and active methanogenesis. TCE dechlorination to DCE is likely occurring under the less reducing conditions of sulfate reduction, with further reductions to VC and ethene occurring under methanogenic conditions. We estimated that about 20% of TCE has dechlorinated to ethene. The analysis of the data enhanced our knowledge of natural in situ transformation and transport processes of CAHs.

Combined removal of a BTEX, TCE, and cis-DCE mixture using Pseudomonas sp. immobilized on scrap tyres.

PubMed

Lu, Qihong; de Toledo, Renata Alves; Xie, Fei; Li, Junhui; Shim, Hojae

2015-09-01

The simultaneous aerobic removal of a mixture of benzene, toluene, ethylbenzene, and o,m,p-xylene (BTEX); cis-dichloroethylene (cis-DCE); and trichloroethylene (TCE) from the artificially contaminated water using an indigenous bacterial isolate identified as Pseudomonas plecoglossicida immobilized on waste scrap tyres was investigated. Suspended and immobilized conditions were compared for the removal of these volatile organic compounds. For the immobilized system, toluene, benzene, and ethylbenzene were completely removed, while the highest removal efficiencies of 99.0 ± 0.1, 96.8 ± 0.3, 73.6 ± 2.5, and 61.6 ± 0.9% were obtained for o-xylene, m,p-xylene, TCE, and cis-DCE, respectively. The sorption kinetics of contaminants towards tyre surface was also evaluated, and the sorption capacity generally followed the order of toluene > benzene > m,p-xylene > o-xylene > ethylbenzene > TCE > cis-DCE. Scrap tyres showed a good capability for the simultaneous sorption and bioremoval of BTEX/cis-DCE/TCE mixture, implying a promising waste material for the removal of contaminant mixture from industrial wastewater or contaminated groundwater.

Degradation of TCE using sequential anaerobic biofilm and aerobic immobilized bed reactor

NASA Technical Reports Server (NTRS)

Chapatwala, Kirit D.; Babu, G. R. V.; Baresi, Larry; Trunzo, Richard M.

1995-01-01

Bacteria capable of degrading trichloroethylene (TCE) were isolated from contaminated wastewaters and soil sites. The aerobic cultures were identified as Pseudomonas aeruginosa (four species) and Pseudomonas fluorescens. The optimal conditions for the growth of aerobic cultures were determined. The minimal inhibitory concentration values of TCE for Pseudomonas sps. were also determined. The aerobic cells were immobilized in calcium alginate in the form of beads. Degradation of TCE by the anaerobic and dichloroethylene (DCE) by aerobic cultures was studied using dual reactors - anaerobic biofilm and aerobic immobilized bed reactor. The minimal mineral salt (MMS) medium saturated with TCE was pumped at the rate of 1 ml per hour into the anaerobic reactor. The MMS medium saturated with DCE and supplemented with xylenes and toluene (3 ppm each) was pumped at the rate of 1 ml per hour into the fluidized air-uplift-type reactor containing the immobilized aerobic cells. The concentrations of TCE and DCE and the metabolites formed during their degradation by the anaerobic and aerobic cultures were monitored by GC. The preliminary study suggests that the anaerobic and aerobic cultures of our isolates can degrade TCE and DCE.

Effect of Fe(III) on 1,1,2,2-tetrachloroethane degradation and vinyl chloride accumulation in wetland sediments of the Aberdeen proving ground

USGS Publications Warehouse

Jones, E.J.P.; Voytek, M.A.; Lorah, M.M.

2004-01-01

1,1,2,2-Tetrachloroethane (TeCA) contaminated groundwater at the Aberdeen Proving Ground discharges through an anaerobic wetland in West Branch Canal Creek, MD, where dechlorination occurred. Two microbially mediated pathways, dichloroelimination and hydrogenolysis, account for most of the TeCA degradation at this site. The dichloroelimination pathways led to the formation of vinyl chloride (VC), a recalcitrant carcinogen of great concern. The effect of adding Fe(III) to TeCA-amended microcosms of wetland sediment was studied. Differences were identified in the TeCA degradation pathway between microcosms treated with amorphous ferric oxyhydroxide (AFO-treated) and untreated (no AFO) microcosms. TeCA degradation was accompanied by a lower accumulation of VC in AFO-treated microcosms than no AFO microcosms. The microcosm incubations and subsequent experiments with the microcosm materials showed that AFO treatment resulted in lower production of VC by shifting TeCA degradation from dichloroelimination pathways to production of a greater proportion of chlorinated ethane products, and decreasing the microbial capability to produce VC from 1,2-dichloroethylene. VC degradation was not stimulated in the presence of Fe(III). Rather, VC degradation occurred readily under methanogenic conditions and was inhibited under Fe(III)-reducing conditions.

Effects of age, sex, and persistent organic pollutants on DNA methylation in children

PubMed Central

Huen, Karen; Yousefi, Paul; Bradman, Asa; Yan, Liying; Harley, Kim G.; Kogut, Katherine; Eskenazi, Brenda; Holland, Nina

2015-01-01

Epigenetic changes such as DNA methylation may be a molecular mechanism through which environmental exposures affect health. Methylation of Alu and long interspersed nucleotide elements (LINE-1) is a well-established measure of DNA methylation often used in epidemiologic studies. Yet, few studies have examined the effects of host factors on LINE-1 and Alu methylation in children. We characterized the relationship of age, sex, and prenatal exposure to persistent organic pollutants (POPs), dichlorodiphenyl trichloroethane (DDT), dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenyl ethers (PBDEs), with DNA methylation in a birth cohort of Mexican-American children participating in the CHAMACOS study. We measured Alu and LINE-1 methylation by pyrosequencing bisulfite-treated DNA isolated from whole blood samples collected from newborns and 9-year old children (n=358). POPs were measured in maternal serum during late pregnancy. Levels of DNA methylation were lower in 9-year olds compared to newborns and were higher in boys compared to girls. Higher prenatal DDT/E exposure was associated with lower Alu methylation at birth, particularly after adjusting for cell type composition (p=0.02 for o,p′ -DDT). Associations of POPs with LINE-1 methylation were only identified after examining the co-exposure of DDT/E with PBDEs simultaneously. Our data suggest that repeat element methylation can be an informative marker of epigenetic differences by age and sex and that prenatal exposure to POPs may be linked to hypomethylation in fetal blood. Accounting for co-exposure to different types of chemicals and adjusting for blood cell types may increase sensitivity of epigenetic analyses for epidemiological studies. PMID:24375655

Persistent Organochlorine Pollutants with Endocrine Activity and Blood Steroid Hormone Levels in Middle-Aged Men

PubMed Central

Emeville, Elise; Giton, Frank; Giusti, Arnaud; Oliva, Alejandro; Fiet, Jean; Thomé, Jean-Pierre; Blanchet, Pascal; Multigner, Luc

2013-01-01

Background Studies relating long-term exposure to persistent organochlorine pollutants (POPs) with endocrine activities (endocrine disrupting chemicals) on circulating levels of steroid hormones have been limited to a small number of hormones and reported conflicting results. Objective We examined the relationship between serum concentrations of dehydroepiandrosterone, dehydroepiandrosterone sulphate, androstenedione, androstenediol, testosterone, free and bioavailable testosterone, dihydrotestosterone, estrone, estrone sulphate, estradiol, sex-hormone binding globulin, follicle-stimulating hormone, and luteinizing hormone as a function of level of exposure to three POPs known to interfere with hormone-regulated processes in different way: dichlorodiphenyl dichloroethene (DDE), polychlorinated biphenyl (PCB) congener 153, and chlordecone. Methods We collected fasting, morning serum samples from 277 healthy, non obese, middle-aged men from the French West Indies. Steroid hormones were determined by gas chromatography-mass spectrometry, except for dehydroepiandrosterone sulphate, which was determined by immunological assay, as were the concentrations of sex-hormone binding globulin, follicle-stimulating hormone and luteinizing hormone. Associations were assessed by multiple linear regression analysis, controlling for confounding factors, in a backward elimination procedure, in multiple bootstrap samples. Results DDE exposure was negatively associated to dihydrotestosterone level and positively associated to luteinizing hormone level. PCB 153 was positively associated to androstenedione and estrone levels. No association was found for chlordecone. Conclusions These results suggested that the endocrine response pattern, estimated by determining blood levels of steroid hormones, varies depending on the POPs studied, possibly reflecting differences in the modes of action generally attributed to these compounds. It remains to be investigated whether this response pattern

Sediment record and atmospheric deposition of brominated flame retardants and organochlorine compounds in Lake Thun, Switzerland: lessons from the past and evaluation of the present.

PubMed

Bogdal, Christian; Schmid, Peter; Kohler, Martin; Müller, Claudia E; Iozza, Saverio; Bucheli, Thomas D; Scheringer, Martin; Hungerbühler, Konrad

2008-09-15

Chronology of brominated fame retardants (BFRs), a class of currentlywidely used chemicals, was compared to the respective historical profiles of legacy organochlorine compounds in three dated sediment cores from a prealpine lake (Lake Thun, Switzerland). Concentrations of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) started to increase in the 1980s-1990s. In the more recent sediment layers, PBDEs still had steady or increasing concentrations, whereas for HBCDs one sediment core revealed a decreasing trend. In contrast to the contemporary BFRs, concentrations of legacy organochlorines, such as polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and dichlorodiphenyl trichloroethane (DDT), peaked in deeper sediment layers deposited some decades ago. Measurements of atmospheric deposition and evaluation of wastewater discharges pointtoward deposition on the lake surface as a relevant input pathway and wastewater as a minor source of POPs in Lake Thun. The effect of the environmental awareness and the regulations taken in the 1970s to reduce environmental pollution of organochlorines is well reflected in the analyzed sediment cores. The sediment burden closely follows estimated time trends of consumption and emission of PCBs and DDT. The current residues in sediment of BFRs are still lower than the historical peak levels of organochlorines. However, current atmospheric deposition of BFRs is similar to deposition of PCBs. Considering the high amount of BFRs presently stocked in the anthroposphere in flame proofed materials, further measures to reduce emissions during BFRs life cycle are recommended to prevent high environmental pollution as it occurred for the organochlorine compounds.

Prenatal exposure to persistent organic pollutants and organophosphate pesticides, and markers of glucose metabolism at birth.

PubMed

Debost-Legrand, Anne; Warembourg, Charline; Massart, Catherine; Chevrier, Cécile; Bonvallot, Nathalie; Monfort, Christine; Rouget, Florence; Bonnet, Fabrice; Cordier, Sylvaine

2016-04-01

Experimental evidence suggests that developmental exposure to persistent organic pollutants (POP) and to some non persistent pesticides may disrupt metabolic regulation of glucose metabolism and insulin secretion, and thereby contribute to the current epidemic of obesity and metabolic disorders. Quasi-experimental situations of undernutrition in utero have provided some information. However, the evidence in humans concerning the role of the prenatal environment in these disorders is contradictory, and little is known about long-term outcomes, such as type 2 diabetes, of prenatal exposure. Our aim was to evaluate the effects of prenatal exposure to POP and organophosphate pesticides on fetal markers of glucose metabolism in a sample of newborns from the Pelagie mother-child cohort in Brittany (France). Dialkylphosphate (DAP) metabolites of organophosphate pesticides were measured in maternal urine collected at the beginning of pregnancy. Cord blood was assayed for polychlorinated biphenyl congener 153 (PCB153), p,p'-dichlorodiphenyl dichloroethene (DDE) and other POP. Insulin and adiponectin were determined in cord blood serum (n=268). A decrease in adiponectin and insulin levels was observed with increasing levels of DDE, but only in girls and not boys. Adiponectin levels were not related to the concentrations of other POP or DAP metabolites. Decreasing insulin levels were observed with increasing PCB153 concentrations. Insulin levels increased with DAP urinary levels. Additional adjustment for BMI z-score at birth modified some of these relations. Our observations bring support for a potential role of organophosphate pesticides and POP in alterations to glucose metabolism observable at birth. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of chlorinated solvents on four species of North American amphibians.

PubMed

McDaniel, T V; Martin, P A; Ross, N; Brown, S; Lesage, S; Pauli, B D

2004-07-01

Tetrachloroethylene (PCE), a dry cleaning and degreasing solvent, can enter groundwater through accidental leaks or spills, and concentrations as high as 75 mg/L have been reported in Canadian aquifers. Amphibians in wetlands receiving contaminated groundwater may be exposed to PCE and its degradation products, but little information is available on the impacts of these compounds on indigenous amphibian species. Acute (96-h static renewal) exposures to PCE and its major degradation products, trichloroethylene (TCE) and cisand trans-dichloroethylene, were conducted on embryos of four North American amphibian species: wood frogs (Rana sylvatica), green frogs (R. clamitans), American toads (Bufo americanus), and spotted salamanders (Ambystoma maculatum). Subsequently, chronic exposures to PCE and TCE were conducted with the larvae of American toads. Both PCE and TCE were teratogenic to amphibian embryos; median effective concentrations (EC50s) for developmental deformities produced by PCE and TCE exposure for wood frogs and green frogs were 12 and 40 mg/L, respectively. Embryonic survivorship, however, was not compromised at these concentrations. American toads were less sensitive; the EC50 for developmental abnormalities was not attained at the highest test concentrations, 45 and 85 mg/L PCE and TCE, respectively. These results are pertinent in assessing the impact of groundwater pollution on an aquifer-fed wetland.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eckhardt, D.A.V.; Pearsall, K.A.

Trichloroethylene (TCE), 1,2-dichloroethylene (DCE), and tetrachloroethylene (PCE) have been detected in water from five public-supply wells and six cooling-water wells that tap the Magothy aquifer at Roosevelt Field. The cooling water is discharged after use to the water table aquifer through a nearby recharge basin and a subsurface drain field. Three plumes of TCE in groundwater have been delineated - the source plume, which has penetrated both aquifers, and two more recent plumes emanating from the two discharge sites in the water-table aquifer. Concentrations of inorganic constituents in the three plumes are the same as those in ambient water inmore » the area. The two secondary plumes discharged cooling water extended at least 1,000 ft south-southeastward in the direction of regional groundwater flow. Pumping at wells screened in the middle and basal sections of the Magothy aquifers, where clay layers are absent and sandy zones provide good vertical hydraulic connection within the aquifer system, has increased the rate of downward contaminant advection. The transient increases in downward movement are cumulative over time and have brought TCE to the bottom of the Magothy aquifer, 500 ft below land surface. 38 refs., 11 figs., 8 tabs.« less

Natural attenuation of chlorinated volatile organic compounds in a freshwater tidal wetland: Field evidence of anaerobic biodegradation

USGS Publications Warehouse

Lorah, Michelle M.; Olsen, Lisa D.

1999-01-01

Field evidence collected along two groundwater flow paths shows that anaerobic biodegradation naturally attenuates a plume of chlorinated volatile organic compounds as it discharges from an aerobic sand aquifer through wetland sediments. A decrease in concentrations of two parent contaminants, trichloroethylene (TCE) and 1,1,2,2‐tetrachloroethane (PCA), and a concomitant increase in concentrations of anaerobic daughter products occurs along upward flow paths through the wetland sediments. The daughter products 1,2‐dichloroethylene, vinyl chloride, 1,1,2‐trichloroethane, and 1,2‐dichloroethane are produced from hydrogenolysis of TCE and from PCA degradation through hydrogenolysis and dichloroelimination (reductive dechlorination) pathways. Total concentrations of TCE, PCA, and their degradation products, however, decrease to below detection levels within 0.15–0.30 m of land surface. The enhanced reductive dechlorination of TCE and PCA in the wetland sediments is associated with the naturally higher concentrations of dissolved organic carbon and the lower redox state of the groundwater compared to the aquifer. This field study indicates that wetlands and similar organic‐rich environments at groundwater/surface‐water interfaces may be important in intercepting groundwater contaminated with chlorinated organics and in naturally reducing concentrations and toxicity before sensitive surface‐water receptors are reached.

Chlorinated organic compounds in ground water at Roosevelt Field, Nassau County, Long Island, New York

USGS Publications Warehouse

Eckhardt, D.A.; Pearsall, K.A.

1989-01-01

Trichloroethylene (TCE), 1,2-dichloroethylene (DCE), and tetrachloroethylene (PCE) have been detected in water from five public-supply wells and six cooling-water wells that tap the Magothy aquifer at Roosevelt Field, a 200-acre area that is now a large shopping mall and office-building complex. The cooling water is discharged after use to the water table (upper glacial) aquifer through a nearby recharge basin and a subsurface drain field. Three plumes of TCE in groundwater have been delineated--the source plume, which has penetrated both aquifers , and two more recent plumes emanating from the two discharge sites in the water-table aquifer. Concentrations of inorganic constituents in the three plumes are the same as those in ambient water in the area. The two secondary plumes discharged cooling water extended at least 1,000 ft south-southeastward in the direction of regional groundwater flow. Pumping at wells screened in the middle and basal sections of the Magothy aquifers, where clay layers are absent and sandy zones provide good vertical hydraulic connection within the aquifer system, has increased the rate of downward contaminant advection. The transient increases in downward movement are cumulative over time and have brought TCE to the bottom of the Magothy aquifer, 500 ft below land surface. (USGS)

Advances in Biodegradation of Multiple Volatile Organic Compounds

NASA Astrophysics Data System (ADS)

Zhang, M.; Yoshikawa, M.

2017-12-01

Bioremediation of soil and groundwater containing multiple contaminants remains a challenge in environmental science and engineering because complete biodegradation of all components is necessary but very difficult to accomplish in practice. This presentation provides a brief overview on advances in biodegradation of multiple volatile organic compounds (VOCs) including chlorinated ethylenes, benzene, toluene and dichloromethane (DCM). Case studies on aerobic biodegradation of benzene, toluene and DCM, and integrated anaerobic-aerobic biodegradation of 7 contaminants, specifically, tetrachloroethylene (PCE), trichloroethylene (TCE), cis-dichloroethylene (cis-DCE), vinyl chloride (VC), DCM, benzene and toluene will be provided. Recent findings based on systematic laboratory experiments indicated that aerobic toluene degradation can be enhanced by co-existence of benzene. Propioniferax, not a known benzene, toluene and DCM degrader can be a key microorganism that involves in biodegradation when the three contaminants co-exist. Integrated anaerobic-aerobic biodegradation is capable of completely degrading the seven VOCs with initial concentrations less than 30 mg/L. Dehalococcoides sp., generally considered sensitive to oxygen, can survive aerobic conditions for at least 28 days, and can be activated during the subsequent anaerobic biodegradation. This presentation may provide a systematic information about biodegradation of multiple VOCs, and a scientific basis for the complete bioremediation of multiple contaminants in situ.

Development and composition of a mixed culture for bioremediation of chlorinated ethenes and ethanes

USGS Publications Warehouse

Jones, E.J.P.; Voytek, M.A.; Lorah, M.M.

2005-01-01

Microbial organisms capable of dechlorinating 1,1,2,2 tetrachloroethane (TeCA) and its chlorinated ethane and ethylene daughter products were enriched in surface sediments collected from the West Branch Canal Creek wetland area, leading to the formation of two mixed cultures using slightly different enrichment methods. Both WBC-1 and WBC-2 were capable of rapid and complete reductive dechlorination of TeCA and its daughter products (1,1,2-trichloroethane, 1,2-dichloroethane, trichloroethylene, 1,2-dichloroethylene, and vinyl chloride) to ethylene, and addition of either culture to wetland sediment and to engineered peat/compost mixtures resulted in significant enhancement of dechlorination. However, the WBC-2 culture supported better sustained activity and was more readily scaled up for application in bioaugmentation treatments, whereas dechlorination activity was gradually lost in WBC-1. The microbial composition of WBC-1 and WBC-2 were determined by cloning and sequencing 500 base pairs of the 16S rDNA gene and the methyl co-reductase. Methanogens identified in the consortia were members of the Order Methanomicrobiales, which includes acetoclastic methanogens. This is an abstract of a paper presented at the Proceedings of the 8th International In Situ and On-Site Bioremediation Symposium (Baltimore, MD 6/6-9/2005).

Biodegradation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) by using Serratia marcescens NCIM 2919.

PubMed

Grewal, Jasneet; Bhattacharya, Amrik; Kumar, Sumit; Singh, Dileep K; Khare, Sunil K

2016-12-01

A solvent tolerant bacterium Serratia marcescens NCIM 2919 has been evaluated for degradation of DDT (1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane). The bacterium was able to degrade up to 42% of initial 50 mg L -1 of DDT within 10 days of incubation. The highlight of the work was the elucidation of DDT degradation pathway in S. marcescens. A total of four intermediates metabolites viz. 2,2-bis (chlorophenyl)-1,1-dichloroethane (DDD), 2,2-bis (chlorophenyl)-1,1-dichloroethylene (DDE), 2,2-bis (chlorophenyl)-1-chloroethylene (DDMU), and 4-chlorobenzoic acid (4-CBA) were identified by GC-Mass and FTIR. 4-CBA was found to be the stable product of DDT degradation. Metabolites preceding 4-CBA were not toxic to strain as reveled through luxuriant growth in presence of varying concentrations of exogenous DDD and DDE. However, 4-CBA was observed to inhibit the growth of bacterium. The DDT degrading efficiency of S. marcescens NCIM 2919 hence could be used in combination with 4-CBA utilizing strains either as binary culture or consortia for mineralization of DDT. Application of S. marcescens NCIM 2919 to DDT contaminated soil, showed 74.7% reduction of initial 12.0 mg kg -1 of DDT after 18-days of treatment.

Year 5 Post-Remediation Biomonitoring of Pesticides and other Contaminants in Marine Waters near the United Heckathorn Superfund Site, Richmond, California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kohn, Nancy P.; Kropp, Roy K.

Marine sediment remediation at the United Heckathorn Superfund Site in Richmond, California, was completed in April 1997. The Record of Decision included a requirement for five years of post-remediation monitoring be conducted in the waterways near the site. The present monitoring year, 2001? 2002, is the fifth and possibly final year of post-remediation monitoring. In March 2002, water and mussel tissues were collected from the four stations in and near Lauritzen Channel that have been routinely monitored since 1997-98. A fifth station in Parr Canal was sampled in Year 5 to document post-remediation water and tissue concentrations there. Dieldrin andmore » dichlorodiphenyl trichloroethane (DDT) were analyzed in water samples and in tissue samples from resident (i.e., naturally occurring) mussels. As in Years 3 and 4, mussels were not transplanted to the study area in Year 5. Year 5 concentrations of dieldrin and total DDT in water and total DDT in tissue were compared with those from Years 1 through 4 of post-remediation monitoring, and with preremediation data from the California State Mussel Watch Program and the Ecological Risk Assessment for the United Heckathorn Superfund Site. Year 5 water samples and mussel tissues were also analyzed for polychlorinated biphenyls (PCB), which were detected in sediment samples during Year 2 monitoring and were added to the water and mussel tissue analyses in 1999. Contaminants of concern in Year 5 water samples were analyzed in both bulk (total) phase and dissolved phase, as were total suspended solids, to evaluate the contribution of particulates to the total contaminant concentration.« less

Persistent organic pollutants (POPs) in populations of the clam Chione californiensis in coastal lagoons of the Gulf of California.

PubMed

Vargas-González, Héctor H; Méndez-Rodríguez, Lía C; García-Hernández, Jaqueline; Mendoza-Salgado, Renato A; Zenteno-Savín, Tania; Arreola-Lizárraga, José A

2016-07-02

This study examines the potential public health risk due to the massive use of organochlorine pesticides (OCs) in agriculture in the Gulf of California. Specimens of the clam Chione californiensis were collected from three coastal lagoons (Yavaros, Altata and Reforma). Sites were classified as polluted/nonpolluted based on the presence/absence of OCs as an indicator of the persistence of these pollutants; in polluted sites, the time elapsed since pesticide application (past or recent) was estimated. Screening values (SV) for protecting human health as per the U.S. Environmental Protection Agency (EPA) were used for risk assessment. OCs detected were ranked according to frequency of occurrence as follows: γ-chlordane (75%) > endrin (54%) > aldrin (48%) > heptachlor, and dichlorodiphenyl-trichloroethane (DDE) (37%) > β-heptachlor epoxide (30%) > lindane (α-BHC, δ-BHC) and endosulphan I (≤ 6%). Specifically, OCs detected at the highest concentration were heptachlor in Yavaros (0.0168 µgg(-1)) and Altata (0.0046 µgg(-1)), and aldrin in Reforma (0.0019 µgg(-1)). β-Heptachlor epoxide in Altata and Reforma was the only OC with a concentration exceeding the EPA Screening Value. From our results and based on the monthly consumption limit set forth by EPA, the maximum safe consumption of clams to avoid a carcinogenic risk derived from β-heptachlor epoxide in the fishing villages of Yavaros and Altata is 4 servings per month (1 serving = 0.227 kg) by a 70-kg person. These findings suggest that concentrations of OCs and their isomers in C. californiensis populations reflect environmental persistence as well as recent inputs of OCs into coastal lagoons in the Gulf of California.

Endophyte-enhanced phytoremediation of DDE-contaminated using Cucurbita pepo: A field trial.

PubMed

Eevers, N; Hawthorne, J R; White, J C; Vangronsveld, J; Weyens, N

2018-03-21

Although the use of the pesticide 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) was banned from the mid-1970s, its most abundant and recalcitrant degradation product, 2,2-bis(p-chlorophenyl)-1,1-dichloro-ethylene (DDE), is still present in terrestrial and aquatic ecosystems worldwide. Zucchini (Cucurbita pepo ssp. pepo) has been shown to accumulate high concentrations of DDE and was proposed for phytoremediation of contaminated soils. We performed a field trial covering a full plant life cycle. C. pepo plants inoculated with the plant growth-promoting endophytic strains Sphingomonas taxi UH1, Methylobacterium radiotolerans UH1, Enterobacter aerogenes UH1, or a consortium combining these 3 strains were grown on a DDE-contaminated field for 100 days. The effects of these inoculations were examined at both the plant level, by evaluating plant weight and plant DDE-content, and at the level of the cultivable and total endophytic communities. Inoculating plants with S. taxi UH1, M. radiotolerans UH1, and the consortium increased plant weight. No significant effects of the inoculations were observed on DDE-concentrations in plant tissues. However, the amount of DDE accumulated by C. pepo plants per growing season was significantly higher for plants that were inoculated with the consortium of the 3 strains. Therefore, inoculation of C. pepo with DDE-degrading endophytes might be promising for phytoremediation applications.

[VC and DCE in groundwater and drainage channel water].

PubMed

Ackermann, A

2004-12-01

In an area used merely for gardening in a downland moor, which is partly transformed to an industrial estate, accidentally a contamination of a drainage channel with VOC's - predominantly chloroethylene (vinyl chloride [VC]) and 1.2-cis-dichloroethylene (DCE) - was found. The ascending ground water leaks into the drainage channels. The dissolved harmful substances (water solubility of VC is 1.6 g/l) can reach the radix range of plants and fruit bosks and can theoretically be incorporated with the water influx. Additionally the water from the drainage channels can be used to water the crops. Six gardens and a housing were involved. In the groundwater of the mainly concerned region max. 5,000 microg/l VOC's (quite predominantly VC and DCE) was measured from 147 samples. In the drainage channel water max. 2,500 microg/l was measured from 52 samples (limit value according to the drinking water ordinance is 10 microg/l). In the sediment of the channel with approximately 60,000 microg/kg VOC was found in dry matter (6 samples). We describe, how the consumer protection dept. dealt with this unexpected situation and what measures were taken. The impact on human health by the contaminated ground and channel water or by means of contaminated plants are determined for tree fruits, potatoes, bulbs and carrots. The soil air was contaminated, but in buildings no harmful compounds were detectioned.

Modelling of sequential groundwater treatment with zero valent iron and granular activated carbon.

PubMed

Bayer, Peter; Finkel, Michael

2005-06-01

Multiple contaminant mixtures in groundwater may not efficiently be treated by a single technology if contaminants possess rather different properties with respect to sorptivity, solubility, and degradation potential. An obvious choice is to use sequenced units of the generally accepted treatment materials zero valent iron (ZVI) and granular activated carbon (GAC). However, as the results of this modelling study suggest, the required dimensions of both reactor units may strongly differ from those expected on the grounds of a contaminant-specific design. This is revealed by performing an analysis for a broad spectrum of design alternatives through numerical experiments for selected patterns of contaminant mixtures consisting of monochlorobenzene, tetrachloroethylene, trichloroethylene (TCE), cis-1,2-dichloroethylene (cis-DCE), and vinyl chloride (VC). It is shown that efficient treatment can be achieved only if competitive sorption effects in the GAC unit as well as the formation of intermediate products in the ZVI unit are carefully taken into account. Cost-optimal designs turned out to vary extremely depending on the prevailing conditions concerning contaminant concentrations, branching ratios, and unit costs of both reactor materials. Where VC is the critical contaminant, due to high initial concentration or extensive production as an intermediate, two options are cost-effective: an oversized ZVI unit with an oversized GAC unit or a pure GAC reactor.

Fifteen-year assessment of a permeable reactive barrier for treatment of chromate and trichloroethylene in groundwater.

PubMed

Wilkin, Richard T; Acree, Steven D; Ross, Randall R; Puls, Robert W; Lee, Tony R; Woods, Leilani L

2014-01-15

The fifteen-year performance of a granular iron, permeable reactive barrier (PRB; Elizabeth City, North Carolina) is reviewed with respect to contaminant treatment (hexavalent chromium and trichloroethylene) and hydraulic performance. Due to in-situ treatment of the chromium source zone, reactive and hydraulic longevity of the PRB has outlived the mobile chromate plume. Chromium concentrations exceeding 3 μg/L have not been detected in regions located hydraulically down-gradient of the PRB. Trichloroethylene treatment has also been effective, although non-constant influent concentrations of trichloroethylene have at times resulted in incomplete dechlorination. Daughter products: cis-1,2-dichloroethylene, vinyl chloride, ethene, and ethane have been observed within and down-gradient of the PRB at levels <10% of the influent trichloroethylene. Analysis of potentiometric surfaces up-gradient and across the PRB suggests that the PRB may currently represent a zone of reduced hydraulic conductivity; however, measurements of the in-situ hydraulic conductivity provide values in excess of 200 m/d in some intervals and indicate no discernible loss of bulk hydraulic conductivity within the PRB. The results presented here are particularly significant because they provide the longest available record of performance of a PRB. The longevity of the Elizabeth City PRB is principally the result of favorable groundwater geochemistry and hydrologic properties of the site. © 2013.

Degradation of 1,1,2,2-tetrachloroethane in a freshwater tidal wetland: Field and laboratory evidence

USGS Publications Warehouse

Lorah, M.M.; Olsen, L.D.

1999-01-01

Degradation reactions controlling the fate of 1,1,2,2-tetrachloroethane (PCA) in a freshwater tidal wetland that is a discharge area for a contaminated aquifer were investigated by a combined field and laboratory study. Samples from nested piezometers and porous-membrane sampling devices (peepers) showed that PCA concentrations decreased and that less chlorinated daughter products formed as the groundwater became increasingly reducing along upward flow paths through the wetland sediments. The cis and trans isomers of 1,2-dichloroethylene (12DCE) and vinyl chloride (VC) were the predominant daughter products detected from degradation of PCA in the field and in microcosms constructed under methanogenic conditions. Significantly lower ratios of cis-12DCE to trans-12DCE were produced by PCA degradation than by degradation of trichloroethylene, a common co-contaminant with PCA. 1,1,2-Trichloroethane (112TCA) and 1,2-dichloroethane (12DCA) occurred simultaneously with 12DCE, indicating simultaneous hydrogenolysis and dichloroelimination of PCA. From an initial PCA concentration of about 1.5 ??mol/L, concentrations of PCA and its daughter products decreased to below detection within a 1.0-m vertical distance in the wetland sediments and within 34 days in the microcosms. The results indicate that natural attenuation of PCA through complete anaerobic biodegradation can occur in wetlands before sensitive surface water receptors are reached.

Water quality in the Withers Swash Basin, with emphasis on enteric bacteria, Myrtle Beach, South Carolina, 1991-93

USGS Publications Warehouse

Guimaraes, W.B.

1995-01-01

Water samples were collected in 1991-93 from Withers Swash and its two tributaries (the Mainstem and KOA Branches) in Myrtle Beach, S.C., and analyzed for physical properties, organic and inorganic constituents, and fecal coliform and streptococcus bacteria. Samples were collected during wet- and dry-weather conditions to assess the water quality of the streams before and after storm runoff. Water samples were analyzed for over 200 separate physical, chemical, and biological constituents. Concentrations of 11 constituents violated State criteria for shellfish harvesting waters, and State Human Health Criteria. The 11 constituents included concentrations of dissolved oxygen, arsenic, lead, cadmium, mercury, chlordane, dieldrin, 1,1,1-trichloroethane, 1,1-dichloroethylene, trichloroethylene, and fecal coliform bacteria. Water samples were examined for the presence of enteric bacteria (fecal coliform and fecal streptococcus) at 46 sites throughout the Withers Swash Basin and 5 sites on the beach and in the Atlantic Ocean. Water samples were collected just upstream from all confluences in order to determine sources of bacterial contamination. Temporally and spatially high concentrations of enteric bacteria were detected throughout the Withers Swash Basin; however, these sporadic bacteria concentrations made it difficult to determine a single source of the contamination. These enteric bacteria concentrations are probably derived from a number of sources in the basin including septic tanks, garbage containers, and the feces of waterfowl and domestic animals.

Core-based intrinsic fiber-optic absorption sensor for the detection of volatile organic compounds

NASA Astrophysics Data System (ADS)

Klunder, Gregory L.; Russo, Richard E.

1995-03-01

A core-based intrinsic fiber-optic absorption sensor has been developed and tested for the detection of volatile organic compounds. The distal ends of transmitting and receiving fibers are connected by a small cylindrical section of an optically clear silicone rubber. The silicone rubber acts both as a light pipe and as a selective membrane into which the analyte molecules can diffuse. The sensor has been used to detect volatile organics (trichloroethylene, 1,1-dichloroethylene, and benzene) in both aqueous solutions and in the vapor phase or headspace. Absorption spectra obtained in the near-infrared (near-IR) provide qualitative and quantitative information about the analyte. Water, which has strong broad-band absorption in the near-IR, is excluded from the spectra because of the hydrophobic properties of the silicone rubber. The rate-limiting step is shown to be the diffusion through the Nernstian boundary layer surrounding the sensor and not the diffusion through the silicone polymer. The rate of analyte diffusion into the sensor, as measured by the t(sub 90) values (the time required for the sensor to reach 90% of the equilibrium value), is 30 min for measurements in aqueous solutions and approximately 3 min for measurements made in the headspace. The limit of detection obtained with this sensor is approximately 1.1 ppm for trichloroethylene in an aqueous solution.

Developments toward a Low-Cost Approach for Long-Term, Unattended Vapor Intrusion Monitoring

PubMed Central

Tolley, William K.

2014-01-01

There are over 450,000 sites contaminated by chemicals in the US. This large number of contaminated sites and the speed of subsurface migration of chemicals pose considerable risk to nearby residences and commercial buildings. The high costs for monitoring around these site stem from the labor involved in placing and replacing the passive sorbent vapor samplers and the resultant laboratory analysis. This monitoring produces sparse data sets that do not track temporal changes well. To substantially reduce costs and better track exposures, less costly, unattended systems for monitoring soil gases and vapor intrusion into homes and businesses are desirable to aid in the remediation of contaminated sites. This paper describes progress toward the development of an inexpensive system specifically for monitoring vapor intrusion; the system can operate repeatedly without user intervention with low detection limits (1 × 10−9, or 1 part-per-billion). Targeted analytes include chlorinated hydrocarbons (dichloroethylene, trichloroethane, trichloroethylene, and perchloroethylene) and benzene. The system consists of a trap-and-purge preconcentrator for vapor collection in conjunction with a compact gas chromatography instrument to separate individual compounds. Chemical detection is accomplished with an array of chemicapacitors and a metal-oxide semiconductor combustibles sensor. Both the preconcentrator and the chromatography column are resistively heated. All components are compatible with ambient air, which serves as the carrier gas for the gas chromatography and detectors. PMID:24903107

Pilot-Scale Demonstration of In-Situ Chemical Oxidation ...

EPA Pesticide Factsheets

A pilot-scale in situ chemical oxidation (ISCO) demonstration, involving subsurface injections of sodium permanganate (NaMnO4), was performed at the US Marine Corp Recruit Depot (MCRD), site 45 (Parris Island (PI), SC). The ground water was originally contaminated with perchloroethylene (PCE) (also known as tetrachloroethylene), a chlorinated solvent used in dry cleaner operations. High resolution site characterization involved multiple iterations of soil core sampling and analysis. Nested micro-wells and conventional wells were also used to sample and analyze ground water for PCE and decomposition products (i.e., trichloroethyelene (TCE), dichloroethylene (c-DCE, t-DCE), and vinyl chloride (VC)), collectively referred to as chlorinated volatile organic compounds (CVOC). This characterization methodology was used to develop and refine the conceptual site model and the ISCO design, not only by identifying CVOC contamination but also by eliminating uncontaminated portions of the aquifer from further ISCO consideration. Direct-push injection was selected as the main method of NaMnO4 delivery due to its flexibility and low initial capital cost. Site impediments to ISCO activities in the source area involved subsurface utilities, including a high pressure water main, a high voltage power line, a communication line, and sanitary and stormwater sewer lines. Utility markings were used in conjunction with careful planning and judicious selection of injection locations. A

Persistent Organic Pollutants (POPs) in the atmosphere of three Chilean cities using passive air samplers.

PubMed

Pozo, Karla; Oyola, Germán; Estellano, Victor H; Harner, Tom; Rudolph, Anny; Prybilova, Petra; Kukucka, Petr; Audi, Ondrej; Klánová, Jana; Metzdorff, America; Focardi, Silvano

2017-05-15

In this study passive air samplers containing polyurethane foam (PUF) disks were deployed in three cities across Chile; Santiago (STG) (n=5, sampling sites), Concepciόn (CON) (n=6) and Temuco (TEM) (n=6) from 2008 to 2009. Polychlorinated biphenyls (PCBs) (7 indicator congeners), chlorinated pesticides hexachlorocyclohexanes (HCHs), dichlorodiphenyl trichloroethanes (DDTs) and flame retardants such as polybrominated diphenyl ethers (PBDEs) were determined by gas chromatography coupled mass spectrometry (GC/MS). A sampling rate (R) typical of urban sites (4m 3 /day) was used to estimate the atmospheric concentrations of individual compounds. PCB concentrations in the air (pg/m 3 ) ranged from ~1-10 (TEM), ~1-40 (STG) and 4-30 (CON). Higher molecular weight PCBs (PCB-153, -180) were detected at industrial sites (in Concepción). The HCHs showed a prevalence of γ-HCH across all sites, indicative of inputs from the use of lindane but a limited use of technical HCHs in Chile. DDTs were detected with a prevalence of p,p'-DDE accounting for ~50% of the total DDTs. PBDE concentrations in air (pg/m 3 ) ranged from 1 to 55 (STG), 0.5 to 20 (CON) and from 0.4 to 10 (TEM), and were generally similar to those reported for many other urban areas globally. The pattern of PBDEs was different among the three cities; however, PBDE-209 was dominant at most of the sites. These results represent one of the few assessments of air concentrations of POPs across different urban areas within the same country. These data will support Chilean commitments as a signatory to the Stockholm Convention on POPs and for reporting as a member country of the Group of Latin America and Caribbean Countries (GRULAC) region. Copyright © 2016 Elsevier B.V. All rights reserved.

Associations of Plasma Concentrations of Dichlorodiphenyldichloroethylene and Polychlorinated Biphenyls with Prostate Cancer: A Case–Control Study in Guadeloupe (French West Indies)

PubMed Central

Emeville, Elise; Giusti, Arnaud; Coumoul, Xavier; Thomé, Jean-Pierre; Blanchet, Pascal

2014-01-01

Background: Long-term exposure to persistent pollutants with hormonal properties (endocrine-disrupting chemicals; EDCs) may contribute to the risk of prostate cancer (PCa). However, epidemiological evidence remains limited. Objectives: We investigated the relationship between PCa and plasma concentrations of universally widespread pollutants, in particular p,p´-dichlorodiphenyl dichloroethene (DDE) and the non-dioxin-like polychlorinated biphenyl congener 153 (PCB-153). Methods: We evaluated 576 men with newly diagnosed PCa (before treatment) and 655 controls in Guadeloupe (French West Indies). Exposure was analyzed according to case–control status. Associations were assessed by unconditional logistic regression analysis, controlling for confounding factors. Missing data were handled by multiple imputation. Results: We estimated a significant positive association between DDE and PCa [adjusted odds ratio (OR) = 1.53; 95% CI: 1.02, 2.30 for the highest vs. lowest quintile of exposure; ptrend = 0.01]. PCB-153 was inversely associated with PCa (OR = 0.30; 95% CI: 0.19, 0.47 for the highest vs. lowest quintile of exposure values; ptrend < 0.001). Also, PCB-153 was more strongly associated with low-grade than with high-grade PCa. Conclusions: Associations of PCa with DDE and PCB-153 were in opposite directions. This may reflect differences in the mechanisms of action of these EDCs; and although our findings need to be replicated in other populations, they are consistent with complex effects of EDCs on human health. Citation: Emeville E, Giusti A, Coumoul X, Thomé JP, Blanchet P, Multigner L. 2015. Associations of plasma concentrations of dichlorodiphenyldichloroethylene and polychlorinated biphenyls with prostate cancer: a case–control study in Guadeloupe (French West Indies). Environ Health Perspect 123:317–323; http://dx.doi.org/10.1289/ehp.1408407 PMID:25493337

PBDEs and other POPs in urban birds of prey partly explained by trophic level and carbon source.

PubMed

Elliott, John E; Brogan, Jason; Lee, Sandi L; Drouillard, Ken G; Elliott, Kyle H

2015-08-15

As urban sprawl and agricultural intensification continue to invade prime wildlife habitat, some animals, even apex predators, are managing to adapt to this new environment. Chemical pollution is one of many stressors that wildlife encounter in urban environments. Predators are particularly sensitive to persistent chemical pollutants because they feed at a high trophic level where such pollution is biomagnified. To examine levels of pollution in urban birds of prey in the Lower Mainland region of British Columbia, Canada, we analyzed persistent organic contaminants in adult birds found dead of trauma injury. The hepatic geometric mean concentration of sum polybrominated diphenyl ethers (∑PBDEs) in 13 Cooper's hawks (Accipiter cooperii) from Greater Vancouver was 1873 ng/g (lipid weight) with one bird reaching 197,000n g/g lipid weight, the highest exposure reported to date for a wild bird. Concentrations of ∑PBDEs, ∑PCBs (polychlorinated biphenyls) and, surprisingly, cyclodiene insecticides were greatest in the urban environment while those of DDE (1,1-dichloroethylene bis[p-chlorophenyl) were highest in a region of intensive agriculture. The level of most chlorinated and brominated contaminants increased with trophic level (δ(15)N). The concentrations of some contaminants, PBDEs in particular, in these birds of prey may have some toxicological consequences. Apex predators in urban environments continue to be exposed to elevated concentrations of legacy pollutants as well as more recent brominated pollutants. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Exposure of Cucurbita pepo to DDE-contamination alters the endophytic community: A cultivation dependent vs a cultivation independent approach.

PubMed

Eevers, N; Hawthorne, J R; White, J C; Vangronsveld, J; Weyens, N

2016-02-01

2,2-bis(p-chlorophenyl)-1,1-dichloro-ethylene (DDE) is the most abundant and persistent degradation product of the pesticide 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) and is encountered in contaminated soils worldwide. Both DDE and DDT are classified as Persistent Organic Pollutants (POPs) due to their high hydrophobicity and potential for bioaccumulation and biomagnification in the food chain. Zucchini (Cucurbita pepo ssp. pepo) has been shown to accumulate high concentrations of DDE and other POPs and has been proposed as a phytoremediation tool for contaminated soils. The endophytic bacteria associated with this plant may play an important role in the remedial process. Therefore, this research focuses on changes in endophytic bacterial communities caused by the exposure of C. pepo to DDE. The total bacterial community was investigated using cultivation-independent 454 pyrosequencing, while the cultivable community was identified using cultivation-dependent isolation procedures. For both procedures, increasing numbers of endophytic bacteria, as well as higher diversities of genera were observed when plants were exposed to DDE. Several bacterial genera such as Stenotrophomonas sp. and Sphingomonas sp. showed higher abundance when DDE was present, while, for example Pseudomonas sp. showed a significantly lower abundance in the presence of DDE. These findings suggest tolerance of different bacterial strains to DDE, which might be incorporated in further investigations to optimize phytoremediation with the possible use of DDE-degrading endophytes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reductive Outer-Sphere Single Electron Transfer Is an Exception Rather than the Rule in Natural and Engineered Chlorinated Ethene Dehalogenation.

PubMed

Heckel, Benjamin; Cretnik, Stefan; Kliegman, Sarah; Shouakar-Stash, Orfan; McNeill, Kristopher; Elsner, Martin

2017-09-05

Chlorinated ethenes (CEs) such as perchloroethylene, trichloroethylene and dichloroethylene are notorious groundwater contaminants. Although reductive dehalogenation is key to their environmental and engineered degradation, underlying reaction mechanisms remain elusive. Outer-sphere reductive single electron transfer (OS-SET) has been proposed for such different processes as Vitamin B 12 -dependent biodegradation and zerovalent metal-mediated dehalogenation. Compound-specific isotope effect ( 13 C/ 12 C, 37 Cl/ 35 Cl) analysis offers a new opportunity to test these hypotheses. Defined OS-SET model reactants (CO 2 radical anions, S 2- -doped graphene oxide in water) caused strong carbon (ε C = -7.9‰ to -11.9‰), but negligible chlorine isotope effects (ε Cl = -0.12‰ to 0.04‰) in CEs. Greater chlorine isotope effects were observed in CHCl 3 (ε C = -7.7‰, ε Cl = -2.6‰), and in CEs when the exergonicity of C-Cl bond cleavage was reduced in an organic solvent (reaction with arene radical anions in glyme). Together, this points to dissociative OS-SET (SET to a σ* orbital concerted with C-Cl breakage) in alkanes compared to stepwise OS-SET (SET to a π* orbital followed by C-Cl cleavage) in ethenes. The nonexistent chlorine isotope effects of chlorinated ethenes in all aqueous OS-SET experiments contrast strongly with pronounced Cl isotope fractionation in all natural and engineered reductive dehalogenations reported to date suggesting that OS-SET is an exception rather than the rule in environmental transformations of chlorinated ethenes.

Multivariate optimization for the simultaneous bioremoval of BTEX and chlorinated aliphatic hydrocarbons by Pseudomonas plecoglossicida.

PubMed

Li, Junhui; de Toledo, Renata Alves; Shim, Hojae

2017-01-05

This study aimed to evaluate the effects of some major parameters on the cometabolic removal of cis-1,2-dichloroethylene (cis-DCE) and trichloroethylene (TCE), mixed with benzene, toluene, ethylbenzene, and xylenes, by an indigenous bacterial isolate Pseudomonas plecoglossicida. Such statistical methodologies as hierarchical cluster analysis heat map and principal component analysis were applied to better evaluate the effects of major parameters (soil pH, temperature, moisture, and cis-DCE/TCE concentrations) on the biological process. The bioremoval experiments were carried out in microcosms containing soil slurry, and the headspace concentrations of contaminants were analyzed by gas chromatography. The optimal bioremoval conditions for the mixture were soil water content >110%, pH 8-9, and temperature 15-20°C, while the cis-DCE/TCE concentration did not significantly affect the mixture bioremoval within the tested range (∼10mg per kg soil). Under the optimal conditions, benzene (97.7%), toluene (96.3%), and ethylbenzene (89.8%) were almost completely removed, while cis-DCE (24.5%), TCE (29.0%), m,p-xylene (36.3%), and o-xylene (29.6%) showed lower removal efficiencies. The obtained results would help to better design a remediation technology to be applied to the sites contaminated with mixed wastes, and the statistical methodologies used in this study appear to be very efficient and could serve as a template for optimization. Copyright © 2016 Elsevier B.V. All rights reserved.

Post-Remediation Biomonitoring of Pesticides and Other Contaminants in Marine Waters and Sediment Near the United Heckathorn Superfund Site, Richmond, California

DOE Office of Scientific and Technical Information (OSTI.GOV)

LD Antrim; NP Kohn

This report, PNNL-1 3059 Rev. 1, was published in July 2000 and replaces PNNL-1 3059 which is dated October 1999. The revision corrects tissue concentration units that were reported as dry weight but were actually wet weight, and updates conclusions based on the correct reporting units. Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in February 1999 from four stations near Lauritzen Canal in Richmond, California, for Year 2 of post-remediation monitoring of marine areas near the United Heckathom Site. Dieldrin and dichlorodiphenyl trichloroethane (DDT) were analyzed inmore » water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Concentrations of dieldrin and total DDT in water and total DDT in tissue were compared with Year 1 of post-remediation monitoring, and with preremediation data from the California State Mussel Watch program (tissue s) and the Ecological Risk Assessment for the United Heckathorn Superfund Site (tissues and water). Mussel tissues were also analyzed for polychlorinated biphenyls (PCB), which were detected in sediment samples. Chlorinated pesticide concentrations in water samples were similar to preremediation levels and did not meet remediation goals. Mean dieldrin concentrations in water ranged from 0.62 ng/L to 12.5 ng/L and were higher than the remediation goal (0.14 ng/L) at all stations. Mean total DDT concentrations in water ranged from 14.4 ng/L to 62.3 ng/L and exceeded the remediation goal (0.59 ng/L) at all stations. The highest concentrations of both DDT and dieldrin were found at the Lauritzen Canal/End station. Despite exceedence of the remediation goals, chlorinated pesticide concentrations in Lauritzen Canal water samples were notably lower in 1999 than in 1998. PCBS were not detected in water samples in 1999.« less

Endocrine disrupters: a review of some sources, effects, and mechanisms of actions on behaviour and neuroendocrine systems.

PubMed

Frye, C A; Bo, E; Calamandrei, G; Calzà, L; Dessì-Fulgheri, F; Fernández, M; Fusani, L; Kah, O; Kajta, M; Le Page, Y; Patisaul, H B; Venerosi, A; Wojtowicz, A K; Panzica, G C

2012-01-01

Some environmental contaminants interact with hormones and may exert adverse consequences as a result of their actions as endocrine disrupting chemicals (EDCs). Exposure in people is typically a result of contamination of the food chain, inhalation of contaminated house dust or occupational exposure. EDCs include pesticides and herbicides (such as dichlorodiphenyl trichloroethane or its metabolites), methoxychlor, biocides, heat stabilisers and chemical catalysts (such as tributyltin), plastic contaminants (e.g. bisphenol A), pharmaceuticals (i.e. diethylstilbestrol; 17α-ethinylestradiol) or dietary components (such as phytoestrogens). The goal of this review is to address the sources, effects and actions of EDCs, with an emphasis on topics discussed at the International Congress on Steroids and the Nervous System. EDCs may alter reproductively-relevant or nonreproductive, sexually-dimorphic behaviours. In addition, EDCs may have significant effects on neurodevelopmental processes, influencing the morphology of sexually-dimorphic cerebral circuits. Exposure to EDCs is more dangerous if it occurs during specific 'critical periods' of life, such as intrauterine, perinatal, juvenile or puberty periods, when organisms are more sensitive to hormonal disruption, compared to other periods. However, exposure to EDCs in adulthood can also alter physiology. Several EDCs are xenoestrogens, which can alter serum lipid concentrations or metabolism enzymes that are necessary for converting cholesterol to steroid hormones. This can ultimately alter the production of oestradiol and/or other steroids. Finally, many EDCs may have actions via (or independent of) classic actions at cognate steroid receptors. EDCs may have effects through numerous other substrates, such as the aryl hydrocarbon receptor, the peroxisome proliferator-activated receptor and the retinoid X receptor, signal transduction pathways, calcium influx and/or neurotransmitter receptors. Thus, EDCs, from varied

Chemical contamination assessment in mangrove-lined Caribbean coastal systems using the oyster Crassostrea rhizophorae as biomonitor species.

PubMed

Aguirre-Rubí, Javier R; Luna-Acosta, Andrea; Etxebarría, Nestor; Soto, Manu; Espinoza, Félix; Ahrens, Michael J; Marigómez, Ionan

2018-05-01

This paper aims to contribute to the use of mangrove cupped oyster, Crassostrea rhizophorae, as a biomonitor species for chemical contamination assessment in mangrove-lined Caribbean coastal systems. Sampling was carried out in eight localities (three in Nicaragua and five in Colombia) with different types and levels of contamination. Oysters were collected during the rainy and dry seasons of 2012-2013 and the tissue concentrations of metals, polycyclic aromatic hydrocarbons (PAHs), and persistent organic pollutants (POPs) were determined. Low tissue concentrations of metals (except Hg) and PAHs; moderate-to-high tissue concentrations of Hg, hexachlorocyclohexanes (HCHs), and dichlorodiphenyl-trichloroethanes (DDTs); detectable levels of chlorpyrifos, polychlorinated biphenyls (PCBs) (mainly CB28, CB118, CB138 and CB 153) and brominated diphenyl ethers 85 (BDE85); and negligible levels of musks were recorded in Nicaraguan oysters. A distinct profile of POPs was identified in Colombia, where the tissue concentrations of PCBs and synthetic musk fragrances were low to moderate, and Ag, As, Cd, Pb, and PAHs ranged from moderate to extremely high. Overall, the values recorded for HCHs, DDTs and PCBs in Nicaraguan mangrove cupped oysters greatly exceeded the reference values in tissues of C. rhizophorae from the Wider Caribbean Region, whereas only the levels of PCBs were occasionally surpassed in Colombia. Different contaminant profiles were distinguished between oysters from Nicaragua and Colombia in radar plots constructed using the main groups of contaminants (metals, PAHs, musks, PCBs, and organochlorine pesticides (OCPs)). Likewise, integrated pollution indices revealed differences in the levels of contaminants. Moreover, the profiles and levels in oyster tissues also varied with season. Thus, principal component analysis clearly discriminated Nicaraguan and Colombian localities and, especially in Colombia, seasonal trends in chemical contamination and differences

Numerical examination of the factors controlling DNAPL migration through a single fracture.

PubMed

Reynolds, D A; Kueper, B H

2002-01-01

The migration of five dense nonaqueous phase liquids (DNAPLs) through a single fracture in a clay aquitard was numerically simulated with the use of a compositional simulator. The effects of fracture aperture, fracture dip, matrix porosity, and matrix organic carbon content on the migration of chlorobenzene, 1,2-dichloroethylene, trichloroethylene, tetra-chloroethylene, and 1,2-dibromoethane were examined. Boundary conditions were chosen such that DNAPL entry into the system was allowed to vary according to the stresses applied. The aperture is the most important factor of those studied controlling the migration rate of DNAPL through a single fracture embedded in a clay matrix. Loss of mass to the matrix through diffusion does not significantly retard the migration rate of the DNAPL, particularly in larger aperture fractures (e.g., 50 microm). With time, the ratio of diffusive loss to the matrix to DNAPL flux into the fracture approaches an asymptotic value lower than unity. The implication is that matrix diffusion cannot arrest the migration of DNAPL in a single fracture. The complex relationships between density, viscosity, and solubility that, to some extent, govern the migration of DNAPL through these systems prevent accurate predictions without the use of numerical models. The contamination potential of the migrating DNAPL is significantly increased through the transfer of mass to the matrix. The occurrence of opposite concentration gradients within the matrix can cause dissolved phase contamination to exist in the system for more than 1000 years after the DNAPL has been completely removed from the fracture.

Geohydrology and ground-water quality at the Pueblo Depot activity landfill near Pueblo, Colorado

USGS Publications Warehouse

Watts, Kenneth R.; Ortiz, Roderick F.

1990-01-01

Groundwater samples were collected from the shallow unconfined aquifer at the Pueblo Depot Activity (Colorado) landfill and downstream from the landfill. The Pueblo Depot Activity is a U.S. Department of the Army facility in southeastern Colorado about 15 miles east of Pueblo, Colorado. The land-fill is underlain by upland alluvial terrace deposits that overlie a thick and almost impermeable shale. Saturated thickness of the aquifer generally is from 5 to 10 feet. Groundwater flow at the landfill is to the south-southeast toward the Arkansas River valley. Though not hydraulically connected to the upland terrace deposits, the alluvium underlying the Arkansas River valley may be recharged by groundwater that is discharged from seeps at the contact of the upland terrace deposits and the Pierre Shale. The water is classified as a mixed-cation mixed-anion type water that has concentrations of dissolved solids of 710 to 1,810 mg/L. Dissolved-solids concentrations increase downgradient. Chemical analysis, done to determine possible contamination of the groundwater, indicated that concentrations of trichloroethylene ranged from 5.2 to 2,900 microg/L and of trans-1,2-dichloroethylene ranged from 5 to 720 microg/L. The areal distribution of these volatile organic compounds indicate that there possibly are two sources of contamination of groundwater at the landfill, one upgradient from the landfill and the other within the landfill. Analysis of water samples from wells and seeps offsite and downgradient from the landfill did not indicate either contaminant in groundwater from the alluvial aquifer underlying the Arkansas River valley. (USGS)

Site remediation using photocatalytic VOC destruction of chlorinated hydrocarbons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brunet, R.A.H.; Pearcey, R.; Kittrell, J.R.

1999-07-01

An innovative environmental technology has been developed and demonstrated for cost-effective control of toxic air emissions, such as trichloroethylene (TCE) and perchloroethylene (PCE), found in soil and groundwater at hazardous waste sites and in industrial effluents. The technology uses UV light and a proprietary photocatalyst to adsorb and destroy pollutants at ambient conditions, even with high humidity. Air stripping and soil vapor extraction efficiently transfer the pollutants to the gas phase, where they can be economically treated by photocatalysis without the risk of hazardous by-product formation. The AIR2000 photocatalytic technology was successfully installed at the Stamina Mills Superfund site inmore » Rhode Island, where a commercial scale unit is treating 700 cfm of up to 1,000 ppm TCE, mixed with PCE, dichloroethylene (DCE), trichloroethane (TCA), and vinyl chloride (VC) produced through a combination of soil vapor extraction (SVE) and air stripping. As part of the EPA SITE program, the system was monitored for overall destruction removal efficiency (DRE) and hazardous by-product formation. A DRE in excess of 99% was reported over the first four months of operation, with greater than 99.99% DRE achieved, without production of hazardous by-products. The operating cost of the system is approximately 20% of activated carbon adsorption, which provides approximately $1,500,000 in cost savings over the life of the Stamina Mills project. The Adsorption Integrated Reaction (AIR) process is the recipient of the 1997 SBIR Technology of the Year award, the 1998 EPA Environmental Technology Innovator Award, and the 1998 R and D 100 Award.« less

Transboundary pollution: Persistent organochlorine pesticides in migrant birds of the Southwestern United States and Mexico

USGS Publications Warehouse

Mora, Miguel A.

1997-01-01

The hypothesis that migratory birds accumulate persistent organochlorine pesticides (POPs) during the winter in Latin America has been prevalent for many years, particularly since 1,1,1-trichloro-2,2–bis(p-chlorophenyl)ethane (DDT) was banned in the United States in 1972. It has been suggested that peregrine falcons (Falco peregrinus), black-crowned night herons (Nycticorax nycticorax), white-faced ibises (Plegadis chihi), various migratory waterfowl and shorebirds, and other avian species accumulate higher concentrations of POPs while on migration or on their wintering grounds in Latin America. Nonetheless, the data obtained thus far are limited, and there is no clear pattern to suggest that such accumulation occurs on a widespread basis. In this review wildlife contaminant studies conducted along the U.S.-Mexico border and throughout Mexico are discussed. The results for the most part seem to indicate that no major accumulation of 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene) (DDE), the most persistent organochlorine compound, has occurred or been reported for most parts of Mexico. The majority of the DDE values in birds from Mexico were similar to those reported in birds from the southwestern United States during the same years. More work needs to be done, particularly in those cotton-producing areas of Mexico where DDT was applied heavily in the past (e.g., Chiapas and Michoacan). Because DDT is still used for malaria control and may still be used in agriculture in Chiapas, this state is probably the one where most migrant species would still be at a significant risk of increased accumulation of DDE and DDT.

Physiological characterization of a broad spectrum reductively dechlorinating consortium

USGS Publications Warehouse

Lorah, M.M.; Majcher, E.; Jones, E.; Driedger, G.; Dworatzek, S.; Graves, D.

2005-01-01

A wetland sediment-derived microbial consortium (WBC-2) was developed by the US Geological Survey and propagated in vitro to large quantities by SiREM Laboratory for potential use in bioaugmentation applications. On the basis of bench-scale tests, the consortium could completely dechlorinate 1,1,2,2-tetrachloroethylene, tetrachloroethylene, trichloroethylene, 1,1,2-trichloroethane, cis- and trans-1,2-dichoroethylene, 1,1-dichloroethylene, 1,2-dichloroethane, and vinyl chloride in culture medium. Batch microcosms were carried out under anaerobic conditions in culture medium with neutral pH and with pH adjusted from acidic (pH 4, 5, and 6) to alkaline (pH 8 and 9). To evaluate oxygen sensitivity of WBC-2, an aliquot was removed from an anaerobic culture vessel and poured into smaller containers on the bench top where a series of oxygen exposures were applied to the culture by bubbling ambient air through the culture at a rate of ??? 100 mL/min. Chlorinated methanes tended to inhibit activity of a wide range of microorganisms. Although toxicity effects from CT addition were observed with WBC-2 in liquid culture at 3 mg/L concentration, WBC-2 in the columns could maintain degradation of CT and chloroform (CF) and of the chlorinated ethanes and ethylenes at CT and CF concentrations of 10 and 20 mg/L, respectively. This is an abstract of a paper presented at the Proceedings of the 8th International In Situ and On-Site Bioremediation Symposium (Baltimore, MD 6/6-9/2005).

The fate of chlorinated aliphatics in anaerobic treatment under transient loading

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiu, Y.C.

1993-01-01

A CSTR with dispersed-growth anaerobic bacteria that simultaneously remove COD and chlorinated aliphatics was used. Seven chlorinated aliphatics (methylene chloride, chloroform, carbon tetrachloride, 1,1,1-trichloroethane, 1,1-dichloroethylene, trichloroethylene, and tetrachloroethylene) were biotransformed into lower-chlorinated compounds by anaerobic treatment, utilizing propionic acid (HPr) or acetic acid (HAc). The microorganisms supplied with HAc grew and were sustained at higher BSS concentrations (4,500 to 11,000 mg/L) than those with HPr (2,000 to 5,000 mg/L). The anaerobic treatment process has a considerable potential for acclimation to and biotransformation of toxic chlorinated aliphatics. For providing a safe operation range, the maximum loading rates of the chlorinated aliphaticsmore » are defined as the observed daily injection of those compounds which resulted in 50% activity of the biomass. Based on the reactor volume, the maximum chlorinated compound loading rates to the microorganisms metabolizing HPr were from 0.4 to 90 mg/L-day, while the rates ranged from 0.6 to 190 mg/L-day for the microorganisms metabolizing HAc. When based on biomass, the maximum loading rates of the microorganisms metabolizing HPr were from 0.2 to 26 mg/g cell-day, while rates for the microorganisms metabolizing HAc ranged from 0.1 to 19 mg/g cell-day. Anaerobic microorganisms have higher resistance to chlorinated aliphatic alkenes than alkanes, and can biotransform about 0.04 to 68 pound chlorinated aliphatics while simultaneously metabolizing 1,000 pounds COD. Therefore, within the safe operation range, the anaerobic process can stabilize organic pollution at a high rate while still biotransforming chlorinated aliphatics.« less

Spatial distribution of organochlorine contaminants in soil, sediment, and fish in Bikini and Enewetak Atolls of the Marshall Islands, Pacific Ocean.

PubMed

Wang, Jun; Caccamise, Sarah A L; Wu, Liejun; Woodward, Lee Ann; Li, Qing X

2011-08-01

Several nuclear tests were performed at Enewetak and Bikini Atolls in the Marshall Islands between 1946 and 1958. The events at Bikini Atoll involved several ships that were tested for durability during nuclear explosions, and 24 vessels now rest on the bottom of the Bikini lagoon. Nine soil samples were collected from different areas on the two islands of the atoll, and eighteen sediment, nine fish, and one lobster were collected in the vicinity of the sunken ships. Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polychlorinated terphenyls (PCTs) in these samples were analyzed using gas chromatography/ion trap mass spectrometry (GC/ITMS). The average recoveries ranged from 78% to 104% for the different PCB congeners. The limits of detection (LOD) for PCBs, PCTs, DDE, DDT, and dieldrin ranged 10-50 pg g(-1). Some fish from Enewetak contained PCBs at a concentration range of 37-137 ng g(-1), dry weight (dw), and most of the soils from Enewetak showed evidence of PCBs (22-392 ng g(-1)dw). Most of the Bikini lagoon sediment samples contained PCBs, and the highest was the one collected from around the Saratoga, an aircraft carrier (1555 ng g(-1)dw). Some of the fish samples, most of the soil samples, and only one of the sediment samples contained 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene (DDE) and PCBs. In addition to PCBs, the soils from Enewetak Atoll contained PCTs. PCTs were not detected in the sediment samples from Bikini Atoll. The results suggest local pollution sources of PCBs, PCTs, and OCPs. Copyright © 2011. Published by Elsevier Ltd.

OECD validation of the Hershberger assay in Japan: phase 2 dose response of methyltestosterone, vinclozolin, and p,p'-DDE.

PubMed

Yamasaki, Kanji; Sawaki, Masakuni; Ohta, Ryo; Okuda, Hirokazu; Katayama, Seiichi; Yamada, Tomoya; Ohta, Takafumi; Kosaka, Tadashi; Owens, William

2003-12-01

The Organisation for Economic Co-operation and Development has initiated the development of new guidelines for the screening and testing of potential endocrine disruptors. The Hershberger assay is one of the assays selected for validation based on the need for in vivo screening to detect androgen agonists or antagonists by measuring the response of five sex accessory organs and tissues of castrated juvenile male rats: the ventral prostate, the seminal vesicles with coagulating glands, the levator ani and bulbocavernosus muscle complex, the Cowper's glands, and the glans penis. The phase 1 feasibility demonstration stage of the Hershberger validation program has been successfully completed with a single androgen agonist and a single antagonist as reference substances. The phase 2 validation program employs a range of additional androgen agonists and antagonists as well as 5alpha-reductase inhibitors. Seven Japanese laboratories have contributed phase 2 validation studies of the Hershberger assay using methyltestosterone, vinclozolin, and 2,2-bis (4-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE). The methyltestosterone doses were 0, 0.05, 0.5, 5, and 50 mg/kg/day, and the vinclozolin and p,p'-DDE doses were 0, 3, 10, 30, and 100 mg/kg/day. All chemicals were orally administered by gavage for 10 consecutive days. In the antagonist version of the assay using vinclozolin and p,p'-DDE, 0.2 mg/kg/day of testosterone propionate was coadministered by subcutaneous injection. All five accessory sex preproductive organs and tissues consistently responded with statistically significant changes in weight within a narrow window. Therefore, the Japanese studies support the Hershberger assay as a reliable and reproducible screening assay for the detection of androgen agonistic and antagonistic effects.

Integrated Anaerobic-Aerobic Biodegradation of Multiple Contaminants Including Chlorinated Ethylenes, Benzene, Toluene, and Dichloromethane.

PubMed

Yoshikawa, Miho; Zhang, Ming; Toyota, Koki

2017-01-01

Complete bioremediation of soils containing multiple volatile organic compounds (VOCs) remains a challenge. To explore the possibility of complete bioremediation through integrated anaerobic-aerobic biodegradation, laboratory feasibility tests followed by alternate anaerobic-aerobic and aerobic-anaerobic biodegradation tests were performed. Chlorinated ethylenes, including tetrachloroethylene (PCE), trichloroethylene (TCE), cis -dichloroethylene ( cis -DCE), and vinyl chloride (VC), and dichloromethane (DCM) were used for anaerobic biodegradation, whereas benzene, toluene, and DCM were used for aerobic biodegradation tests. Microbial communities involved in the biodegradation tests were analyzed to characterize the major bacteria that may contribute to biodegradation. The results demonstrated that integrated anaerobic-aerobic biodegradation was capable of completely degrading the seven VOCs with initial concentration of each VOC less than 30 mg/L. Benzene and toluene were degraded within 8 days, and DCM was degraded within 20 to 27 days under aerobic conditions when initial oxygen concentrations in the headspaces of test bottles were set to 5.3% and 21.0%. Dehalococcoides sp., generally considered sensitive to oxygen, survived aerobic conditions for 28 days and was activated during the subsequent anaerobic biodegradation. However, degradation of cis -DCE was suppressed after oxygen exposure for more than 201 days, suggesting the loss of viability of Dehalococcoides sp., as they are the only known anaerobic bacteria that can completely biodegrade chlorinated ethylenes to ethylene. Anaerobic degradation of DCM following previous aerobic degradation was complete, and yet-unknown microbes may be involved in the process. The findings may provide a scientific and practical basis for the complete bioremediation of multiple contaminants in situ and a subject for further exploration.

Long-term performance monitoring for a permeable reactive barrier at the U.S. Coast Guard Support Center, Elizabeth City, North Carolina.

PubMed

Puls, R W; Blowes, D W; Gillham, R W

1999-08-12

A continuous hanging iron wall was installed in June, 1996, at the U. S. Coast Guard (USCG) Support Center near Elizabeth City, NC, United States, to treat overlapping plumes of chromate and chlorinated solvent compounds. The wall was emplaced using a continuous trenching machine whereby native soil and aquifer sediment was removed and the iron simultaneously emplaced in one continuous excavation and fill operation. To date, there have been seven rounds (November 1996, March 1997, June 1997, September 1997, December 1997, March 1998, and June 1998) of performance monitoring of the wall. At this time, this is the only full-scale continuous 'hanging' wall installed as a permeable reactive barrier to remediate both chlorinated solvent compounds and chromate in groundwater. Performance monitoring entails the following: sampling of 10-5 cm PVC compliance wells and 15 multi-level samplers for the following constituents: TCE, cis-dichloroethylene (c-DCE), vinyl chloride, ethane, ethene, acetylene, methane, major anions, metals, Cr(VI), Fe(II), total sulfides, dissolved H(2), Eh, pH, dissolved oxygen, specific conductance, alkalinity, and turbidity. Electrical conductivity profiles have been conducted using a Geoprobe to verify emplacement of the continuous wall as designed and to locate upgradient and downgradient wall interfaces for coring purposes. Coring has been conducted in November, 1996, in June and September, 1997, and March, 1998, to evaluate the rate of corrosion on the iron surfaces, precipitate buildup (particularly at the upgradient interface), and permeability changes due to wall emplacement. In addition to several continuous vertical cores, angled cores through the 0.6-m thick wall have been collected to capture upgradient and downgradient wall interfaces along approximate horizontal flow paths for mineralogic analyses.

Potential of isotope analysis (C, Cl) to identify dechlorination mechanisms

NASA Astrophysics Data System (ADS)

Cretnik, Stefan; Thoreson, Kristen; Bernstein, Anat; Ebert, Karin; Buchner, Daniel; Laskov, Christine; Haderlein, Stefan; Shouakar-Stash, Orfan; Kliegman, Sarah; McNeill, Kristopher; Elsner, Martin

2013-04-01

Chloroethenes are commonly used in industrial applications, and detected as carcinogenic contaminants in the environment. Their dehalogenation is of environmental importance in remediation processes. However, a detailed understanding frequently accounted problem is the accumulation of toxic degradation products such as cis-dichloroethylene (cis-DCE) at contaminated sites. Several studies have addressed the reductive dehalogenation reactions using biotic and abiotic model systems, but a crucial question in this context has remained open: Do environmental transformations occur by the same mechanism as in their corresponding in vitro model systems? The presented study shows the potential to close this research gap using the latest developments in compound specific chlorine isotope analysis, which make it possible to routinely measure chlorine isotope fractionation of chloroethenes in environmental samples and complex reaction mixtures.1,2 In particular, such chlorine isotope analysis enables the measurement of isotope fractionation for two elements (i.e., C and Cl) in chloroethenes. When isotope values of both elements are plotted against each other, different slopes reflect different underlying mechanisms and are remarkably insensitive towards masking. Our results suggest that different microbial strains (G. lovleyi strain SZ, D. hafniense Y51) and the isolated cofactor cobalamin employ similar mechanisms of reductive dechlorination of TCE. In contrast, evidence for a different mechanism was obtained with cobaloxime cautioning its use as a model for biodegradation. The study shows the potential of the dual isotope approach as a tool to directly compare transformation mechanisms of environmental scenarios, biotic transformations, and their putative chemical lab scale systems. Furthermore, it serves as an essential reference when using the dual isotope approach to assess the fate of chlorinated compounds in the environment.

Biomonitoring of Environmental Status and Trends (BEST) Program: Environmental contaminants, health indicators, and reproductive biomarkers in fish from the Mobile, Apalachicola-Chattahoochee-Flint, Savannah, and Pee Dee River Basins

USGS Publications Warehouse

Hinck, Jo Ellen; Blazer, Vicki; Denslow, Nancy D.; Echols, Kathy R.; Gale, Robert W.; May, Tom W.; Claunch, Rachael; Wieser, Carla; Anderson, Patrick J.; Coyle, James J.; Gross, Timothy S.; Tillitt, Donald E.

2007-01-01

Largemouth bass (Micropterus salmoides) and common carp (Cyprinus carpio) were collected from 13 sites in 4 river basins in the southeastern United States to document spatial trends in accumulative contaminants, health indicators, and reproductive biomarkers. Organochlorine residues, 2,3,7,8- tetrachlorodibenzo-p-dioxin-like activity (TCDD-EQ), and elemental contaminants were measured in composite samples of whole fish, grouped by species and gender, from each site. Fish were field-examined for external and internal anomalies, selected organs were weighed to compute somatic indices, and tissue and fluid samples were preserved for fish health and reproductive biomarker analyses. Mercury concentrations in bass samples from all sites exceeded toxicity thresholds for mammals [>0.1 micrograms per gram wet weight (ug/g ww)], fish (>0.2 ug/g ww), and birds (>0.3 ug/g ww) and were greatest (>0.5 ug/g ww) in samples from the Alabama River at Eureka Landing, Alabama; the Mobile River at Bucks, Alabama; the Apalachicola River at Blountstown, Florida; the Savannah River at Sylvania, Georgia; and the Pee Dee River at Bucksport, South Carolina. Selenium concentrations were relatively high (>0.75 ug/g ww) in fish from the Tombigbee River at Lavaca, Alabama; the Mobile River at Bucks; and the Chattahoochee River at Omaha, Georgia compared to those from other sites. Concentrations of 2,2-bis (p-chlorophenyl)- 1,1-dichloroethylene (p,p'-DDE) were high in fish from the Chattahoochee River at Omaha and the Mobile River near Bucks, which was near a 2,2-bis (p-chlorophenyl)-1,1- dichloroethylene (DDT) formulating facility that historically discharged into the lower Mobile River. Toxaphene concentrations in fish from the Flint River near Albany, Georgia (60-100 nanograms per gram (ng/g) ww) may pose a risk to fish. Concentrations of other formerly used (total chlordanes, dieldrin, endrin, aldrin, mirex, and hexachlorobenzene) and currently used (pentachlorobenzene, pentachloroanisole

Chronic toxicity of a mixture of chlorinated alkanes and alkenes in ICR mice.

PubMed

Wang, Fun-In; Kuo, Min-Liang; Shun, Chia-Tung; Ma, Yee-Chung; Wang, Jung-Der; Ueng, Tzuu-Huei

2002-02-01

The aim of this study was to determine the chronic toxicity of a mixture of chlorinated alkanes and alkenes (CA) consisting of chloroform, 1,1-dichloroethane, 1,1-dichloroethylene, 1,1,1-trichloroethane, trichloroethylene, and tetrachloroethylene. These chlorinated organic solvents were present in the underground water near an electronic appliances manufactory in Taoyuan, Taiwan. Male and female weanling ICR mice were treated with low-, medium-, and high-dose CA mixtures in drinking water for 16 and 18 mo, respectively. A significant number of male mice treated with the high-dose CA mixture developed tail alopecia and deformation, which was not prominent in CA-treated female mice. Medium- and high-dose CA mixtures induced marginal increases of liver and lung weights, blood urea nitrogen, and serum creatinine levels in male mice. In female mice, the high-dose CA mixture increased liver, kidney, and uterus and ovary total weights, without affecting serum biochemistry parameters. CA mixtures had no effects on the total glutathione content or the level of glutathione S-transferase activity in the livers and kid- neys of male and female mice. Treatments with CA mixtures produced a trend of increasing frequency of hepatocelluar neoplasms in male mice, compared to male and female controls and CA-treated female mice. The high-dose CA mixture induced a significantly higher incidence of mammary adenocarcinoma in female mice. The calculated odds ratios of mammary adenocarcinoma in female mice induced by low-, medium-, and high-dose CA mixtures were 1.14, 1.37, and 3.53 times that of the controls, respectively. The low-dose CA mixture induced a higher incidence of cysts and inflammation in and around the ovaries. This study has demonstrated that the CA mixture is a potential carcinogen to male and female mice. These animal toxicology data may be important in assessing the health effects of individuals exposed to the CA mixture.

Comparison of Reductive Dechlorination of Chlorinated Ethylene in Batch and Continuous-Flow Reactor

NASA Astrophysics Data System (ADS)

Park, S.; Jonghwan, L.; Hong, U.; Kim, N.; Ahn, H.; Lee, S.; Kim, Y.

2010-12-01

A 1.28 L-Batch reactor and continuous-flow stirred tank reactor (CFSTR) fed with formate and trichloriethene (TCE) were operated for 120 days and 72 days, respectively, to study the effect of formate as electron donor on reductive dechlorination of TCE to cis-1,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethylene (ETH). In batch reactor, injected 60 μmol TCE was completely degraded in presence of 20% hydrogen gas (H2) in less than 8 days by Evanite culture (300 mg-soluble protein) with ability to completely degrade tetrachloroethene (PCE) and TCE to ETH under anaerobic conditions. To determine the effect of formate as electron donor instead of H2, about 3 or 11 mmol of formate injected into batch-reactor every 15 days was enough to support H2 for dechlorination of c-DCE to VC and ETH. Soluble protein concentration of Evanite culture during the batch test increased from 300 mg to 688 mg for 120 days. In CFSTR test, TCE was fed continuously at 9.9 ppm (75.38 μmol/L) and the influent formate feed concentration increased stepwise from 1.3 mmol/L to 14.3 mmol/L. Injected TCE was accumulated at HRT 18 days for 13 days, but TCE was completed degraded at HRT 36 days without accumulation during left of experiment period, getting H2 from fermentative hydrogen production of injected formate. Although c-DCE was also accumulated for 23 days after CFSTR operation, it reached steady-state without accumulation in presence of excessive formate. However, since c-DCE in CFSTR was not completely dechlorinated, we will determine the transcriptional level of enzyme involved in reductive dechlorination of TCE, c-DCE, and VC in our future work.

Organochloride pesticides induced hepatic ABCG5/G8 expression and lipogenesis in Chinese patients with gallstone disease

PubMed Central

Ji, Guixiang; Xu, Cheng; Sun, Haidong; Liu, Qian; Hu, Hai; Gu, Aihua; Jiang, Zhao-Yan

2016-01-01

Background Organochlorine pesticides (OCPs) are one kind of persistent organic pollutants. Although they are reported to be associated with metabolic disorders, the underlying mechanism is unclear. We explored the association of OCPs with gallstone disease and its influence on hepatic lipid metabolism. Materials and Methods OCPs levels in omentum adipose tissues from patients with and without gallstone disease between 2008 and 2011 were measured by GC-MS. Differences of gene expression involved in hepatic lipid metabolism and hepatic lipids content were compared in liver biopsies between groups with high and low level of OCPs. Using HepG2 cell lines, the influence on hepatic lipid metabolism by individual OCP was evaluated in vitro. Results In all patients who were from non-occupational population, there were high levels of β-hexachlorocyclohexane (β-HCH) and p',p'-dichloroethylene (p',p'-DDE) accumulated in adipose tissues. Both β-HCH and p', p'-DDE levels were significantly higher in adipose tissues from patients with gallstone disease (294.3± 313.5 and 2222± 2279 ng/g of lipid) than gallstone-free controls (282.7± 449.0 and 2025±2664 ng/g of lipid, P< 0.01) and they were strongly related with gallstone disease (P for trend = 0.0004 and 0.0138). Furthermore, higher OCPs in adipose tissue led to increase in the expression of hepatic cholesterol transporters ABCG5 and G8 (+34% and +27%, P< 0.01) and higher cholesterol saturation index in gallbladder bile, and induced hepatic fatty acids synthesis, which was further confirmed in HepG2 cells. Conclusion OCPs might enhance hepatic secretion of cholesterol into bile via ABCG5/G8 which promoting gallstone disease as well as lipogenesis. PMID:27203212

Satellite telemetry and prey sampling reveal contaminant sources to Pacific Northwest Ospreys.

PubMed

Elliott, John E; Morrissey, Christy A; Henny, Charles J; Inzunza, Ernesto Ruelas; Shaw, Patrick

2007-06-01

Migratory behavior can be an important factor in determining contaminant exposure in avian populations. Accumulation of organochlorine (OC) pesticides while birds are wintering in tropical regions has been cited often as the reason for high concentrations in migrant populations. To explore this issue, we satellite tracked 16 Ospreys (Pandion haliaetus) over the period 1996-2003 from breeding sites in British Columbia, Canada, and integrated the results into a database on 15 Ospreys that were satellite tracked over the period 1995-1999, from breeding locations in Washington and Oregon, USA. Data on wintering sites of 31 Ospreys in Mexico and Central America were used for spatially targeted sampling of prey fish. Concentrations of the main organochlorine contaminant, p,p'-dichloro-diphenyl-dichloroethylene (DDE), in fish composites from Mexico ranged from 0.005 to 0.115 nicrog/g wet mass. Significant differences existed among fish families in p,p'-DDE, total dichloro-diphenyl-trichloroethane (sigmaDDT), sigmachlordanes, and total polychlorinated biphenyls (sigmaPCBs). Catfish (family Ariidae) generally had significantly higher levels of DDT metabolites and other organochlorine contaminants compared to other fish families collected. Differences in prey contaminant levels were detected among the collection sites around coastal Mexico, with fish from Veracruz State generally having higher levels of DDT metabolites, sigmachlordanes, sigmaPCBs, and hexachlorobenzene. Eggs collected from 16 nests throughout the Pacific Northwest (nine from British Columbia, seven from Oregon and Washington) where Ospreys had been satellite tagged, showed marked variation in levels of DDT metabolites (p,p'-DDE; range 0.02-10.14 microg/g). Wintering site had no significant effect on contaminant concentrations in sample eggs from those specific Ospreys; rather concentrations of p,p'-DDE, were predicted by breeding sites with highest levels in eggs of Ospreys breeding in the lower Columbia

Results of a long-term study of vapor intrusion at four large buildings at the NASA Ames Research Center.

PubMed

Brenner, David

2010-06-01

Most of the published empirical data on indoor air concentrations resulting from vapor intrusion of contaminants from underlying groundwater are for residential structures. The National Aeronautics and Space Administration (NASA) Research Park site, located in Moffett Field, CA, and comprised of 213 acres, is being planned for redevelopment as a collaborative research and educational campus with associated facilities. Groundwater contaminated with hydrocarbon and halogenated hydrocarbon volatile organic compounds (VOCs) is the primary environmental medium of concern at the site. Over a 15-month period, approximately 1000 indoor, outdoor ambient, and outdoor ambient background samples were collected from four buildings designated as historical landmarks using Summa canisters and analyzed by the U.S. Environmental Protection Agency TO-15 selective ion mode. Both 24-hr and sequential 8-hr samples were collected. Comparison of daily sampling results relative to daily background results indicates that the measured trichloroethylene (TCE) concentrations were primarily due to the subsurface vapor intrusion pathway, although there is likely some contribution due to infiltration of TCE from the outdoor ambient background concentrations. Analysis of the cis-1,2-dichloroethylene concentrations relative to TCE concentrations with respect to indoor air concentrations and the background air support this hypothesis; however, this indicates that relative contributions of the vapor intrusion and infiltration pathways vary with each building. Indoor TCE concentrations were also compared with indoor benzene and background benzene concentrations. These data indicate significant correlation between background benzene concentrations and the concentration of benzene in the indoor air, indicating benzene was present in the indoor air primarily through infiltration of outdoor air into the indoor space. By comparison, measured TCE indoor air concentrations showed a significantly different

An assessment of natural biotransformation of petroleum hydrocarbons and chlorinated solvents at an aquifer plume transect

NASA Astrophysics Data System (ADS)

Skubal, Karen L.; Barcelona, Michael J.; Adriaens, Peter

2001-05-01

Field biogeochemical characterization and laboratory microcosm studies were performed to assess the potential for future biotransformation of trichloroethylene (TCE) and toluene in a plume containing petroleum hydrocarbons and chlorinated solvents at the former Wurtsmith Air Force Base in Oscoda, MI. In situ terminal electron accepting processes (TEAPs), contaminant composition and microbial phylogeny were studied at a plume transect 100 m downgradient of the source. The presence of reduced electron acceptors, relevant microbial communities, and elevated dissolved methane and carbon dioxide concentrations at the transect, as well as downgradient accumulation of BTEX metabolites and dechlorination products, indicated that past or current reductive dechlorination at the transect was likely driven by BTEX biodegradation in the methanogenic zone. However, TCE and toluene mineralization in sediment-groundwater microcosms without added electron acceptors did not exceed 5% during 300 days of incubation and was nearly invariant with original sediment TEAP, even following amendments of nitrogen and phosphorus. Mineralization rates were on the order of 0.0015-0.03 μmol/g day. After 8 months, microcosms showed evidence of methanogenesis, but CH 4 and CO 2 production arose from the degradation of contaminants other than toluene. Cis-dichloroethylene was observed in only one methanogenic microcosm after more than 500 days. It appears likely that spatially and temporally dynamic redox zonation at the plume transect will prevent future sustained reductive dehalogenation of highly chlorinated solvents, for during the course of a year, the predominant TEAP at the highly contaminated water table shifted from methanogenesis to iron- and sulfate-reduction. It is recommended that biotransformation studies combine considerations of long-term, spatially relevant changes in redox zonation with laboratory-scale studies of electron donor utilization and cometabolic substrate transformation

Natural attenuation of trichloroethylene in fractured shale bedrock.

PubMed

Lenczewski, M; Jardine, P; McKay, L; Layton, A

2003-07-01

This paper describes one of the first well-documented field examples of natural attenuation of trichloroethylene (TCE) in groundwater in a fractured shale bedrock. The study was carried out adjacent to a former waste burial site in Waste Area Grouping 5 (WAG5) on the Oak Ridge Reservation, Oak Ridge, TN. A contaminant plume containing TCE and its daughter products were detected downgradient from the buried waste pits, with most of the contamination occurring in the upper 6 m of the bedrock. The monitoring well array consists of a 35-m-long transect of multilevel sampling wells, situated along a line between the waste pits and a seep which discharges into a small stream. Concentrations of volatile organic carbons (VOCs) were highest in the waste trenches and decreased with distance downgradient towards the seep. Sampling wells indicated the presence of overlapping plumes of TCE, cis-dichloroethylene (cDCE), vinyl chloride (VC), ethylene, ethane, and methane, with the daughter products extending further downgradient than the parent (TCE). This type of distribution suggests anaerobic biodegradation. Measurements of redox potential at the site indicated that iron-reduction, sulfate reduction, and potentially methanogensis were occurring and are conducive to dechlorination of TCE. Bacteria enrichment of groundwater samples revealed the presence of methanotrophs, methanogens, iron-reducing bacteria and sulfate-reducing bacteria, all of which have previously been implicated in anaerobic biodegradation of TCE. 16S rDNA sequence from DNA extracted from two wells were similar to sequences of organisms previously implicated in the anaerobic biodegradation of chlorinated solvents. The combined data strongly suggest that anaerobic biodegradation of the highly chlorinated compounds is occurring. Aerobic biodegradation may also be occurring in oxygenated zones, including near a seep where groundwater exits the site, or in the upper bedrock during seasonal fluctuations in water

OECD validation of the Hershberger assay in Japan: phase 2 dose response of methyltestosterone, vinclozolin, and p,p'-DDE.

PubMed Central

Yamasaki, Kanji; Sawaki, Masakuni; Ohta, Ryo; Okuda, Hirokazu; Katayama, Seiichi; Yamada, Tomoya; Ohta, Takafumi; Kosaka, Tadashi; Owens, William

2003-01-01

The Organisation for Economic Co-operation and Development has initiated the development of new guidelines for the screening and testing of potential endocrine disruptors. The Hershberger assay is one of the assays selected for validation based on the need for in vivo screening to detect androgen agonists or antagonists by measuring the response of five sex accessory organs and tissues of castrated juvenile male rats: the ventral prostate, the seminal vesicles with coagulating glands, the levator ani and bulbocavernosus muscle complex, the Cowper's glands, and the glans penis. The phase 1 feasibility demonstration stage of the Hershberger validation program has been successfully completed with a single androgen agonist and a single antagonist as reference substances. The phase 2 validation program employs a range of additional androgen agonists and antagonists as well as 5alpha-reductase inhibitors. Seven Japanese laboratories have contributed phase 2 validation studies of the Hershberger assay using methyltestosterone, vinclozolin, and 2,2-bis (4-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE). The methyltestosterone doses were 0, 0.05, 0.5, 5, and 50 mg/kg/day, and the vinclozolin and p,p'-DDE doses were 0, 3, 10, 30, and 100 mg/kg/day. All chemicals were orally administered by gavage for 10 consecutive days. In the antagonist version of the assay using vinclozolin and p,p'-DDE, 0.2 mg/kg/day of testosterone propionate was coadministered by subcutaneous injection. All five accessory sex preproductive organs and tissues consistently responded with statistically significant changes in weight within a narrow window. Therefore, the Japanese studies support the Hershberger assay as a reliable and reproducible screening assay for the detection of androgen agonistic and antagonistic effects. PMID:14644666

Prenatal organochlorine compound exposure, rapid weight gain, and overweight in infancy.

PubMed

Mendez, Michelle A; Garcia-Esteban, Raquel; Guxens, Mónica; Vrijheid, Martine; Kogevinas, Manolis; Goñi, Fernando; Fochs, Silvia; Sunyer, Jordi

2011-02-01

Although it has been hypothesized that fetal exposure to endocrine-disrupting chemicals may increase obesity risk, empirical data are limited, and it is uncertain how early in life any effects may begin. We explored whether prenatal exposure to several organochlorine compounds (OCs) is associated with rapid growth in the first 6 months of life and body mass index (BMI) later in infancy. Data come from the INMA (Infancia y Medio-Ambiente) Child and Environment birth cohort in Spain, which recruited 657 women in early pregnancy. Rapid growth during the first 6 months was defined as a change in weight-for-age z-scores > 0.67, and elevated BMI at 14 months, as a z-score ≥ the 85th percentile. Generalized linear models were used to estimate the risk of rapid growth or elevated BMI associated with 2,2-bis(p-chlorophenyl)-1,1-dichloroethylene (DDE), hexachlorobenzene, β-hexachlorohexane, and polychlorinated biphenyls in first-trimester maternal serum. After multivariable adjustment including other OCs, DDE exposure above the first quartile was associated with doubling of the risk of rapid growth among children of normal-weight (BMI < 25 kg/m2), but not overweight, mothers. DDE was also associated with elevated BMI at 14 months (relative risk per unit increase in log DDE = 1.50; 95% confidence interval, 1.11-2.03). Other OCs were not associated with rapid growth or elevated BMI after adjustment. In this study we found prenatal DDE exposure to be associated with rapid weight gain in the first 6 months and elevated BMI later in infancy, among infants of normal-weight mothers. More research exploring the potential role of chemical exposures in early-onset obesity is needed.

Polychlorinated biphenyls and organochlorine pesticides in plasma and the embryonic development in Lake Erie water snakes (Nerodia sipedon insularum) from Pelee Island, Ontario, Canada (1999).

PubMed

Bishop, C A; Rouse, J D

2006-10-01

From three locations along a 34-km shoreline of Pelee Island, Ontario, 30 gravid female Lake Erie water snakes (Nerodia sipedon insularum) were sampled to determine the organochlorine (OC) contaminant levels in plasma and the number of live and dead embryos present in the body cavity. Plasma was analyzed for 59 polychlorinated biphenyl (PCB) congeners and 14 organochlorine pesticides. Concentrations of pesticides were low (< or =0.1 ng/g wet wt) in all snakes, but there was significant variation in mean PCB concentrations in plasma from among the sampling locations on Pelee Island. Snakes (n = 5) from the West shore and dock area of the island had significantly higher PCB concentrations (90.4 +/- 15.0 ng/g wet wt) in plasma than those from Lighthouse Point (n = 5; 34.4 +/- 13 ng/g wet wt) and the south shore of the island (n = 5; 29.4 +/- 16.3 ng/g wet wt). Body mass of the female snakes ranged from 252 to 880 g, and mean masses were not significantly different among sample sites. The number of live embryos found ranged from 13 to 46 female snakes and no dead embryos were detected. There were significant positive correlations among body mass, snout-vent length, and number of young per female. There were no significant correlations among body mass, snout-vent length, number of young per female, or per-gram body mass of female snakes and contaminant concentrations in plasma. It was concluded that an interim estimate of a no-effect level on embryonic survival in N. sipedon insularum may be a maximum average concentration of 90.4 ng/g wet wt PCBs and a maximum average concentration of 3.6 ng/g wet wt p,p'-dichloro-diphenyl-dichloroethylene in plasma.

Aliphatic and chlorinated alkenes and epoxides as inducers of alkene monooxygenase and epoxidase activities in Xanthobacter strain Py2.

PubMed Central

Ensign, S A

1996-01-01

The inducible nature of the alkene oxidation system of Xanthobacter strain Py2 has been investigated. Cultures grown with glucose as the carbon source did not contain detectable levels of alkene monooxygenase or epoxidase, two key enzymes of alkene and epoxide metabolism. Upon addition of propylene to glucose-grown cultures, alkene monooxygenase and epoxidase activities increased and after an 11-h induction period reached levels of specific activity comparable to those in propylene-grown cells. Addition of chloramphenicol or rifampin prevented the increase in the enzyme activities. Comparison of the banding patterns of proteins present in cell extracts revealed that polypeptides with molecular masses of 43, 53, and 57 kDa accumulate in propylene-grown but not glucose-grown cells. Pulse-labeling of glucose-grown cells with [35S]methionine and [35S]cysteine revealed that the 43-, 53-, and 57-kDa proteins, as well as two additional polypeptides with molecular masses of 12 and 21 kDa, were newly synthesized upon exposure of cells to propylene or propylene oxide. The addition to glucose-grown cells of a variety of other aliphatic and chlorinated alkenes and epoxides, including ethylene, vinyl chloride (1-chloroethylene), cis- and trans-1,2-dichloroethylene, 1-chloropropylene, 1,3-dichloropropylene, 1-butylene, trans-2-butylene, isobutylene, ethylene oxide, epichlorohydrin (3-chloro-1,2-epoxypropane), 1,2-epoxybutane, cis- and trans-2,3-epoxybutane, and isobutylene oxide stimulated the synthesis of the five propylene-inducible polypeptides as well as increases in alkene monooxygenase and epoxidase activities. In contrast, acetylene, and a range of aliphatic and chlorinated alkanes, did not stimulate the synthesis of the propylene-inducible polypeptides or the increase in alkene monooxygenase and epoxidase activities. PMID:8572713

Characterization of ambient volatile organic compounds and their sources in Beijing, before, during, and after Asia-Pacific Economic Cooperation China 2014

NASA Astrophysics Data System (ADS)

Li, J.; Xie, S. D.; Zeng, L. M.; Li, L. Y.; Li, Y. Q.; Wu, R. R.

2015-07-01

Ambient volatile organic compounds (VOCs) were measured using an online system, gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID), in Beijing, China, before, during, and after Asia-Pacific Economic Cooperation (APEC) China 2014, when stringent air quality control measures were implemented. Positive matrix factorization (PMF) was applied to identify the major VOC contributing sources and their temporal variations. The secondary organic aerosols potential (SOAP) approach was used to estimate variations of precursor source contributions to SOA formation. The average VOC mixing ratios during the three periods were 86.17, 48.28, and 72.97 ppbv, respectively. The mixing ratios of total VOC during the control period were reduced by 44 %, and the mixing ratios of acetonitrile, halocarbons, oxygenated VOCs (OVOCs), aromatics, acetylene, alkanes, and alkenes decreased by approximately 65, 62, 54, 53, 37, 36, and 23 %, respectively. The mixing ratios of all measured VOC species decreased during control, and the most affected species were chlorinated VOCs (chloroethane, 1,1-dichloroethylene, chlorobenzene). PMF analysis indicated eight major sources of ambient VOCs, and emissions from target control sources were clearly reduced during the control period. Compared with the values before control, contributions of vehicular exhaust were most reduced, followed by industrial manufacturing and solvent utilization. Reductions of these three sources were responsible for 50, 26, and 16 % of the reductions in ambient VOCs. Contributions of evaporated or liquid gasoline and industrial chemical feedstock were slightly reduced, and contributions of secondary and long-lived species were relatively stable. Due to central heating, emissions from fuel combustion kept on increasing during the whole campaign; because of weak control of liquid petroleum gas (LPG), the highest emissions of LPG occurred in the control period. Vehicle-related sources were the most important

Characterization of ambient volatile organic compounds and their sources in Beijing, before, during, and after Asia-Pacific Economic Cooperation China 2014

NASA Astrophysics Data System (ADS)

Li, J.; Xie, S. D.; Zeng, L. M.; Li, L. Y.; Li, Y. Q.; Wu, R. R.

2015-04-01

Ambient volatile organic compounds (VOCs) were measured using an online system, gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID), in Beijing, China, before, during and after Asia-Pacific Economic Cooperation (APEC) China 2014, when stringent air quality control measures were implemented. Positive matrix factorization (PMF) was applied to identify the major VOC contributing sources and their temporal variations. The secondary organic aerosols potential (SOAP) approach was used to estimate variations of precursor source contributions to SOA formation. The average VOC mixing ratios during the three periods were 86.17, 48.28, and 72.97 ppbv, respectively. The mixing ratios of total VOC during the control period were reduced by 44%, and the mixing ratios of acetonitrile, halocarbons, oxygenated VOCs (OVOCs), aromatics, acetylene, alkanes, and alkenes decreased by approximately 65, 62, 54, 53, 37, 36, and 23%, respectively. The mixing ratios of all measured VOC species decreased during control, and the most affected species were chlorinated VOCs (chloroethane, 1,1-dichloroethylene, chlorobenzene). PMF analysis indicated eight major sources of ambient VOCs, and emissions from target control sources were clearly reduced during the control period. Contributions of vehicular exhaust were most reduced (19.65 ppbv, the contributions before the control period minus the values after the control period), followed by industrial manufacturing (10.29 ppbv) and solvent utilization (6.20 ppbv). Contributions of evaporated or liquid gasoline and industrial chemical feedstock were slightly reduced, with values of 2.85 and 0.35 ppbv, respectively. Contributions of secondary and long-lived species were relatively stable. Due to central heating, emissions from fuel combustion kept on increasing during the whole campaign; because of weak control of liquid petroleum gas (LPG), the highest emissions of LPG occurred in the control period. Vehicle-related sources were

Serum levels of organochlorine pesticides in the French adult population: the French National Nutrition and Health Study (ENNS), 2006-2007.

PubMed

Saoudi, Abdessattar; Fréry, Nadine; Zeghnoun, Abdelkrim; Bidondo, Marie-Laure; Deschamps, Valérie; Göen, Thomas; Garnier, Robert; Guldner, Laurence

2014-02-15

Although most organochlorine (OC) pesticides were banned in France in the 1970s and 1980s, they remain a source of public concern. Because of their high persistence in the environment, they are still detected in foodstuffs, leading to continued human exposure. The purpose of this study was to assess the distribution of serum organochlorine (OC) pesticides in the French adult population and to identify the main risk factors for p,p'-dichlorodiphenyl dichlorethylene (DDE), β-hexachlorocyclohexane (β-HCH) and hexachlorobenzene (HCB). The selected OC pesticides (HCB, DDE, DDT, α-HCH, β-HCB and γ-HCH) were measured in serum samples collected in 2006-2007 from 386 persons (aged 18-74 years) randomly selected among the participants in the clinical and biological component of the French Nutrition and Health Survey (Etude Nationale Nutrition Santé [ENNS]), a cross-sectional survey carried out in the general population. Collected data included biological samples, socio-demographic characteristics, and data about environmental and occupational exposure factors. Of the six OC pesticides investigated, the highest concentrations were observed for HCB, β-HCH and DDE. Median serum concentrations were as follows: 22.8 ng/g lipid for HCB, 0.74 and 27.0 ng/g lipid, respectively, for α- and ß-HCH, and 3.8 and 104.6 ng/g lipid, respectively, for DDT and DDE. Lindane (γ-HCH) was detected in approximately 10% of the sample. OC pesticide levels in serum in French adults were higher (except for DDT and DDE) than those observed in American, Canadian and German populations and generally lower than or in the same range as those observed in other European countries. The low serum DDT/DDE ratio in the present study (3.7%) would suggest that the concentrations observed for these two OC pesticides were mainly the result of past exposure. The most important predictors of serum DDE, HCB and β-HCH concentrations among the French adult population included individual factors (age, gender

Streambed-material characteristics and surface-water quality, Green Pond Brook and tributaries, Picatinny Arsenal, New Jersey, 1983-90

USGS Publications Warehouse

Storck, D.A.; Lacombe, Pierre

1996-01-01

This report presents the results of a study designed to determine whether Green Pond Brook and its tributaries contain contaminated streambed sediments and to characterize the quaity of water in the brook. Results of previous investigations at Picatinny Arsenal, Morris County, New Jersey, indicate that significant contamination of ground water, surface water, and soil is present at the arsenal. Forty-five streambed-material samples were collected for analysis to determine whether contaminants have migrated to the brook from the surrounding area. Samples were analyzed for trace elements, base/neutral- and acid-etractable compounds, insecticides, and other constituents. Results of an electromagnetic-conductivity and natural-gamma-ray survey were used to describe the distribution of particle sizes in streambed and substreambed sediments. Historical results of analyses of streambed-material and surface-water samples also are presented. Samples of streambed material from three areas in Green Pond Brook and its tributaries contained organic and (or) inorganic constituents in concentrations greater than those typically found at the arsenal. These areas are Green Pond Brook, from the area near the outflow of Picatinny Lake downstream to Farley Avenue; Bear Swamp Brook, from the area near building 241 downstream to the confluence with Green Pond Brook; and Green Pond Brook, from the open burning area downstream to the dam near building 1178. Contaminants identified include trace elements, polynuclear aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine insecticides. Surface water in Green Pond Brook contained several volatile organic compounds, including trichloroethylene, tetrachloroethylene, and 1,2-dichloroethylene, at maximum concen- trations of 3.8, 4.6, and 11 micrograms per liter, respectively. Volatilization is expected to remove volatile organic compounds in the steep, fast- flowing reaches of the brook. No organic or inorganic constituents were

Satellite telemetry and prey sampling reveal contaminant sources to pacific northwest ospreys

USGS Publications Warehouse

Elliott, J.E.; Morrissey, C.A.; Henny, C.J.; Inzunza, E.R.; Shaw, P.

2007-01-01

Migratory behavior can be an important factor in determining contaminant exposure in avian populations. Accumulation of organochlorine (OC) pesticides while birds are wintering in tropical regions has been cited often as the reason for high concentrations in migrant populations. To explore this issue, we satellite tracked 16 Ospreys (Pandion haliaetus) over the period 1996-2003 from breeding sites in British Columbia, Canada, and integrated the results into a database on 15 Ospreys that were satellite tracked over the period 1995-1999, from breeding locations in Washington and Oregon, USA. Data on wintering sites of 31 Ospreys in Mexico and Central America were used for spatially targeted sampling of prey fish. Concentrations of the main organochlorine contaminant, p,p???-dichloro-diphenyl-dichloroethylene (DDE), in fish composites from Mexico ranged from 0.005 to 0.115 ??g/g wet mass. Significant differences existed among fish families in p,p???-DDE, total dichloro- diphenyltrichloroethane (??DDT), ??chlordanes, and total polychlorinated biphenyls (??PCBs). Catfish (family Ariidae) generally had significantly higher levels of DDT metabolites and other organochlorine contaminants compared to other fish families collected. Differences in prey contaminant levels were detected among the collection sites around coastal Mexico, with fish from Veracruz State generally having higher levels of DDT metabolites, ??chlordanes, ??PCBs, and hexachlorobenzene. Eggs collected from 16 nests throughout the Pacific Northwest (nine from British Columbia, seven from Oregon and Washington) where Ospreys had been satellite tagged, showed marked variation in levels of DDT metabolites (p,p???-DDE; range 0.02-10.14 ??g/g). Wintering site had no significant effect on contaminant concentrations in sample eggs from those specific Ospreys; rather concentrations of p,p???-DDE, were predicted by breeding sites with highest levels in eggs of Ospreys breeding in the lower Columbia River

Probabilistic Human Health Risk Assessment of Chemical Mixtures: Hydro-Toxicological Interactions and Controlling Factors

NASA Astrophysics Data System (ADS)

Henri, C.; Fernandez-Garcia, D.; de Barros, F.

2014-12-01

Improper disposals of hazardous wastes in most industrial countries give rise to severe groundwater contamination problems that can lead to adverse health effects in humans. Therefore risk assessment methods play an important role in population protection by (1) quantifying the impact on human health of an aquifer contamination and (2) aiding the decision making process of to better manage our groundwater resources. Many reactive components such as chlorinated solvent or nitrate potentially experience attenuation processes under common geochemical conditions. Based on this, monitored natural attenuation has become nowadays an attractive remediation solution. However, in some cases, intermediate degradation products can constitute noxious chemical compounds before reaching a harmless chemical form. In these cases, the joint effect of advection-dispersion transport and the species-dependent kinetic reactions and toxicity will dictate the relative importance of the degradation byproducts to the total risk. This renders the interpretation of risk a non-trivial task. In this presentation, we quantify, through a probabilistic framework, the human health risk posed by a chemical mixture in a heterogeneous aquifer. This work focuses on a Perchloroethylene contamination problem followed by the first-order production/biodegradation of its daughter species Trichloroethylene, Dichloroethylene and Vinyl Chlorine that is known to be highly toxic. Uncertainty on the hydraulic conductivity field is considered through a Monte Carlo scheme. A comparative description of human health risk metrics as a function of aquifer heterogeneity and contaminant injection mode is provided by means of a spatial characterization of the lower-order statistical moments and empirical probability density functions of both individual and total risks. Interestingly, we show that the human health risk of a chemical mixture is mainly controlled by a modified Damköhler number that express the joint effect

Methanogenic community development in anaerobic granular bioreactors treating trichloroethylene (TCE)-contaminated wastewater at 37 °C and 15 °C.

PubMed

Siggins, Alma; Enright, Anne-Marie; O'Flaherty, Vincent

2011-04-01

Four expanded granular sludge bed (EGSB) bioreactors were seeded with a mesophilically-grown granular sludge and operated in duplicate for mesophilic (37 °C; R1 & R2) and low- (15°; R3 & R4) temperature treatment of a synthetic volatile fatty acid (VFA) based wastewater (3 kg COD m(-3) d(-1)) with one of each pair (R1 & R3) supplemented with increasing concentrations of trichloroethylene (TCE; 10, 20, 40, 60 mg l(-1)) and one acting as a control. Bioreactor performance was evaluated by % COD removal efficiency and % biogas methane (CH(4)) content. Quantitative Polymerase Chain Reaction (qPCR) was used to investigate the methanogenic community composition and dynamics in the bioreactors during the trial, while specific methanogenic activity (SMA) and toxicity assays were utilized to investigate the activity and TCE/dichloroethylene (DCE) toxicity thresholds of key trophic groups, respectively. At both 37 °C and 15 °C, TCE levels of 60 mg l(-1) resulted in the decline of % COD removal efficiencies to 29% (Day 235) and 37% (Day 238), respectively, and in % biogas CH(4) to 54% (Day 235) and 5% (Day 238), respectively. Despite the inhibitory effect of TCE on the anaerobic digestion process, the main drivers influencing methanogenic community development, as determined by qPCR and Non-metric multidimensional scaling analysis, were (i) wastewater composition and (ii) operating temperature. At the apical TCE concentration both SMA and qPCR of methanogenic archaea suggested that acetoclastic methanogens were somewhat inhibited by the presence of TCE and/or its degradation derivatives, while competition by dechlorinating organisms may have limited the availability of H(2) for hydrogenotrophic methanogenesis. In addition, there appeared to be an inverse correlation between SMA levels and TCE tolerance, a finding that was supported by the analysis of the inhibitory effect of TCE on two additional biomass sources. The results indicate that low-temperature anaerobic

Fish consumption and plasma levels of organochlorines in a female population in Northern Norway.

PubMed

Furberg, Anne-Sofie; Sandanger, Torkjel; Thune, Inger; Burkow, Ivan C; Lun, Eiliv

2002-02-01

Increased cancer incidence and mortality have been found among humans exposed to high levels of organochlorines (OCs), either accidentally or as industrial workers. In order to assess levels of OCs in Norwegian women north of the Arctic Circle and validate self-reported fish consumption as a surrogate measure of organochlorine body burden, concentrations of seven polychlorinated biphenyl (PCB) congeners [IUPAC Nos. CB-105, CB-118, CB-138 (+ CB-163), CB-153, CB-180, CB-183, CB-187], beta-hexachlorocyclohexane (beta-HCH), 2,2'-bis(p-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE) and cis- and trains-chlordane (c-CD and t-CD) were examined in plasma samples of middle-aged women attending for health screening. Altogether, 47 of those invited (81%) completed a questionnaire and donated a suitable blood sample. The ability of questionnaire data to predict plasma levels of OCs was tested in linear and logistic regression analyses. Measured plasma concentrations were in the range reported for the general female population of other Western countries and the relative amounts of PCBs were similar to the circumpolar pattern. Intake of seagulls' eggs was a predictor of PCB congeners CB-138 (+CB-163) (p<0.05) and CB-153 (p<0.01). No other food category was positively associated with any compound. In contrast, duration of residence in the study municipality, body mass index (BMI) and lifetime lactation (months) were the best univariate predictors. There was an increase in beta-HCH, p,p'-DDE and most of the PCBs (p<0.05 for all) with increasing length of time a subject had lived in the municipality. BMI was a positive predictor for beta-HCH (OR=3.10, 95% CI 1.50-6.43, per 5 kgm(-2)), chlordane (OR=2.13, 95% CI 1.12-4.05, per 5 kgm(-2)) and CB-105 and CB-153 (p<0.05 for both). Lactation was negatively associated with all OCs (p<0.05), except chlordane and two of the PCB congeners. Time living in the municipality and lactation explained 34%, of the variance in concentration of total

Ground-water-quality assessment of shallow aquifers in the Front Range Urban Corridor, Colorado, 1954-98

USGS Publications Warehouse

Flynn, Jennifer L.

2003-01-01

.0 milligrams per liter). Nitrate median concentrations are several times greater where the land is cultivated or used for agricultural business, which may reflect use of nitrogen fertilizers and the presence of animal feeding operations. Most inorganic and organic constituents exceeded drinking-water standards in only a small percentage of samples. Exceptions to this include sulfate; nitrate; trace elements aluminum, cadmium, iron, and manganese; and organic compounds 1,1-dichloroethylene, tetrachloroethylene, trichloroethylene, benzene, and dichloromethane.

Assessing Subsurface Bioaugmentation of a Mixed Culture Capable of Chlorinated Solvent Cometabolism via Molecular Methods

NASA Astrophysics Data System (ADS)

Dolan, M. E.; Lim, H. K.; Semprini, L.; Giovanonni, S.; Vergin, K.; McCarty, P. L.; Hopkins, G. D.

2001-12-01

The goal of this project is the successful bioaugmentation of a mixed culture capable of aerobic cometabolism of chlorinated solvent mixtures into an aquifer test zone at Moffett Federal Airfield, CA (Moffett). The test zone consists of two parallel well legs both fed butane and oxygen. One leg will be bioaugmented and the other will serve as an indigenous control. Injection and extraction wells and six (3 per leg) intermediately placed groundwater monitoring points will be frequently monitored for chlorinated solvents, butane, dissolved oxygen, and pH. Groundwater will also be periodically analyzed for microbial content using terminal restriction fragment length polymorphism (T-RFLP) and fluorescence in-situ hybridization (FISH) analyses. In each well leg, two fully-penetrating wells containing solid media will be periodically analyzed for microbial colonization (T-RFLP). The mixed bioaugmentation culture originated from environmental samples taken from Hanford, WA. The culture was enriched on butane and tested for viability in Moffett groundwater and aquifer solids. A clone library was created from the 16S rDNA in the mixed culture and 86 clones were sorted based on RFLP patterns. Complete sequencing of the 16S rDNA gene from the three most prevalent clones revealed 45 clones similar to Acidovorax or Hydrogenophaga, gram negative proteobacterium, and 12 clones similar to Rhodococcus, a gram positive filamentous organism. Fluorescently-labeled rRNA probes were designed for FISH analyses and appropriate restriction enzymes were chosen for T-RFLP analyses based upon the sequence information. Microcosm tests were conducted prior to the initiation of the field study to evaluate butane, 1,1-dichloroethylene (1,1-DCE), and 1,1,1-trichloroethane (TCA) degradation kinetics and microbial community composition. Bioaugmented microcosms began butane utilization sooner than non-bioaugmented ones in the presence and absence of 1,1-DCE, and were able to degrade more 1,1-DCE (up

Interplay between subsurface structural heterogeneity and multi-species reactive transport in human health risk predictions

NASA Astrophysics Data System (ADS)

Henri, C.; Fernandez-Garcia, D.; de Barros, F.

2013-12-01

The increasing presence of toxic chemicals released in the subsurface has led to a rapid growth of social concerns and to the need to develop and employ models that can predict the impact of groundwater contamination in human health under uncertainty. Monitored natural attenuation is a common remediation action in many contamination cases and represents an attractive decontamination method. However, natural attenuation can lead to the production of subspecies of distinct toxicity that may pose challenges in pollution management strategies. The actual threat that these contaminants pose to human health and ecosystems greatly depends on the interplay between the complexity of the geological system and the toxicity of the pollutants and their byproducts. In this work, we examine the interplay between multispecies reactive transport and the heterogeneous structure of the contaminated aquifer on human health risk predictions. The structure and organization of hydraulic properties of the aquifer can lead to preferential flow channels and fast contamination pathways. Early travel times, associated to channeling effects, are intuitively perceived as an indicator for high risk. However, in the case of multi-species systems, early travel times may also lead a limited production of daughter species that may contain higher toxicity as in the case of chlorinated compounds. In this work, we model a Perchloroethylene (PCE) contamination problem followed by the sequential first-order production/biodegradation of its daughter species Trichloroethylene (TCE), Dichloroethylene (DCE) and Vinyl Chlorine (VC). For this specific case, VC is known to be a highly toxic contaminant. By performing numerical experiments, we evaluate transport for two distinct three-dimensional aquifer structures. First, a multi-Gaussian hydraulic conductivity field and secondly, a geostatistically equivalent connected field. These two heterogeneity structures will provide two distinct ranges of mean travel

Ground-water contamination at Wurtsmith Air Force Base, Michigan

USGS Publications Warehouse

Stark, J.R.; Cummings, T.R.; Twenter, F.R.

1983-01-01

A sand and gravel aquifer of glacial origin underlies Wurtsmith Air Force Base in northeastern lower Michigan. The aquifer overlies a thick clay layer at an average depth of 65 feet. The water table is about 10 feet below land surface in the western part of the Base and about 25 feet below land surface in the eastern part. A ground-water divide cuts diagonally across the Base from northwest to southeast. South of the divide, ground water flows to the Au Sable River; north of the divide, it flows to Van Etten Creek and Van Etten Lake. Mathematical models were used to aid in calculating rates of groundwater flow. Rates range from about 0.8 feet per day in the eastern part of the Base to about 0.3 feet per day in the western part. Models also were used as an aid in making decisions regarding purging of contaminated water from the aquifer. In 1977, trichloroethylene was detected in the Air Force Base water-supply system. It had leaked from a buried storage tank near Building 43 in the southeastern part of the Base and moved northeastward under the influence of the natural ground-water gradient and the pumping of Base water-supply wells. In the most highly contaminated part of the plume, concentrations are greater than 1,000 micrograms per liter. Current purge pumping is removing some of the trichloroethylene, and seems to have arrested its eastward movement. Pumping of additional purge wells could increase the rate of removal. Trichloroethylene has also been detected in ground water in the vicinity of the Base alert apron, where a plume from an unknown source extends northeastward off Base. A smaller, less well-defined area of contamination also occurs just north of the larger plume. Trichloroethylene, identified near the waste-treatment plant, seepage lagoons, and the northern landfill area, is related to activities and operations in these areas. Dichloroethylene and trichloroethylene occur in significant quantities westward of Building 43, upgradient from the major

Mass of chlorinated volatile organic compounds removed by Pump-and-Treat, Naval Air Warfare Center, West Trenton, New Jersey, 1996-2010

USGS Publications Warehouse

Lacombe, Pierre J.

2011-01-01

Pump and Treat (P&T) remediation is the primary technique used to contain and remove trichloroethylene (TCE) and its degradation products cis 1-2,dichloroethylene (cDCE) and vinyl chloride (VC) from groundwater at the Naval Air Warfare Center (NAWC), West Trenton, NJ. Three methods were used to determine the masses of TCE, cDCE, and VC removed from groundwater by the P&T system since it became fully operational in 1996. Method 1, is based on the flow volume and concentrations of TCE, cDCE, and VC in groundwater that entered the P&T building as influent. Method 2 is based on withdrawal volume from each active recovery well and the concentrations of TCE, cDCE, and VC in the water samples from each well. Method 3 compares the maximum monthly amount of TCE, cDCE, and VC from Method 1 and Method 2. The greater of the two values is selected to represent the masses of TCE, cDCE and VC removed from groundwater each month. Previously published P&T monthly reports used Method 1 to determine the mass of TCE, cDCE, and VC removed. The reports state that 8,666 pounds (lbs) of TCE, 13,689 lbs of cDCE, and 2,455 lbs of VC were removed by the P&T system during 1996-2010. By using Method 2, the mass removed was determined to be 8,985 lbs of TCE, 17,801 lbs of cDCE, and 3,056 lbs of VC removed, and Method 3, resulted in 10,602 lbs of TCE, 21,029 lbs of cDCE, and 3,496 lbs of VC removed. To determine the mass of original TCE removed from groundwater, the individual masses of TCE, cDCE, and VC (determined using Methods 1, 2, and 3) were converted to numbers of moles, summed, and converted to pounds of original TCE. By using the molar conversion the mass of original TCE removed from groundwater by Methods 1, 2, and 3 was 32,381 lbs, 39,535 lbs, and 46,452 lbs, respectively, during 1996-2010. P&T monthly reports state that 24,805 lbs of summed TCE, cDCE, and VC were removed from groundwater. The simple summing method underestimates the mass of original TCE removed by the P&T system.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

radionuclides (e.g., radium and thorium) were measured at back-ground levels and were eliminated from further consideration. Chemical contaminants identified in wells at the chemical plant area and ordnance works area include nitroaromatic compounds, metals, and inorganic anions. Trichloroethylene (TCE) and 1,2-dichloroethylene (1,2 -DCE) have been detected recently in a few wells near the raffinate pits at the chemical plant.« less

Annually-layered lake sediments reveal strongly increased release of persistent chemicals due to accelerated glacier melting

NASA Astrophysics Data System (ADS)

Anselmetti, Flavio S.; Blüthgen, Nancy; Bogdal, Christian; Schmid, Peter

2010-05-01

Melting glaciers may represent a secondary source of chemical pollutants that have previously been incorporated and stored in the ice. Of particular concern are persistent organic pollutants (POPs), such as the insecticide dichlorodiphenyl trichloroethane (DDT) and industrial chemicals like polychlorinated biphenyls (PCBs), which are hazardous environmental contaminants due to their persistent, bioaccumulative and toxic properties. They were introduced in the 1930s and eventually banned in the 1970s. After release into the environment these chemicals were atmospherically transported to even remote areas such as the Alps and were deposited and stored in glaciers. Ongoing drastic glacier melting due to global warming, which is expected to further accelerate, implies the significance of studying the fate of these 'legacy pollutants'. Proglacial lake sediments provide well-dated and high-resolution archives to reconstruct timing and quantities of such a potentially hazardous remobilization. The goal of this study is to reconstruct the historical inputs of POPs into remote alpine lakes and to investigate the accelerated release of POPs from melting glaciers. Due to their lipophilic character, these chemicals exhibit a high tendency to adsorb to particles whereas concentrations in water are expected to be low. Therefore, quantitative determination in annually-layered lake sediment provides an excellent way to investigate the temporal trend of inputs into lakes that act as particle sinks. For this purpose, sediment cores were sampled from proglacial lakes in the Bernese Alps (Switzerland), which are exclusively fed by glacial melt waters. For comparison, cores were also taken from nearby high-alpine lakes located in non-glaciated catchments, which only should record the initial atmospheric fall-out. Sediment layers were dated by annual varve counting and radionuclide measurements; they cover the time period from the mid 20th century to today. The measured time series of

In situ remediation of chlorinated solvent-contaminated groundwater using ZVI/organic carbon amendment in China: field pilot test and full-scale application.

PubMed

Yang, Jie; Meng, Liang; Guo, Lin

2018-02-01

Chlorinated solvents in groundwater pose threats to human health and the environment due to their carcinogenesis and bioaccumulation. These problems are often more severe in developing countries such as China. Thus, methods for chlorinated solvent-contaminated groundwater remediation are urgently needed. This study presents a technique of in situ remediation via the direct-push amendment injection that enhances the reductive dechlorination of chlorinated solvents in groundwater in the low-permeability aquifer. A field-based pilot test and a following real-world, full-scale application were conducted at an active manufacturing facility in Shanghai, China. The chlorinated solvents found at the clay till site included 1,1,1-trichloroethane (1,1,1-TCA), 1,1-dichloroethane (1,1-DCA), 1,1-dichloroethylene (1,1-DCE), vinyl chloride (VC), and chloroethane (CA). A commercially available amendment (EHC ® , Peroxychem, Philadelphia, PA) combining zero-valent iron and organic carbon was used to treat the above pollutants. Pilot test results showed that direct-push EHC injection efficiently facilitated the in situ reductive remediation of groundwater contaminated with chlorinated solvents. The mean removal rates of 1,1,1-TCA, 1,1-DCA, and 1,1-DCE at 270 days post-injection were 99.6, 99.3, and 73.3%, respectively, which were obviously higher than those of VC and CA (42.3 and 37.1%, respectively). Clear decreases in oxidation-reduction potential and dissolved oxygen concentration, and increases in Fe 2+ and total organic carbon concentration, were also observed during the monitoring period. These indicate that EHC promotes the anaerobic degradation of chlorinated hydrocarbons primarily via long-term biological reductive dechlorination, with instant chemical reductive dechlorination acting as a secondary pathway. The optimal effective time of EHC injection was 0-90 days, and its radius of influence was 1.5 m. In full-scale application, the maximum concentrations of 1,1,1-TCA

Ground-water quality in the West Salt River Valley, Arizona, 1996-98: relations to hydrogeology, water use, and land use

USGS Publications Warehouse

Edmonds, Robert J.; Gellenbeck, Dorinda J.

2002-01-01

February 1998. Analyses of all samples collected from the monitoring wells indicated low concentrations of pesticides and volatile organic compounds. The most frequently detected pesticides were deethylatrazine and atrazine. Trichloromethane (chloroform) and tetrachloroethene (PCE) were the most frequently detected volatile organic compounds in the monitoring wells. Two compounds [dieldrin and 1,1-dichloro-2,2-bis(p-dichlorodiphenyl)ethylene (DDE)], decomposition products of two banned pesticides, aldrin and dichlorodiphenylethylene (DDT), were detected at low concentrations in samples analyzed for the agricultural land-use study. In the West Salt River Valley, a high concentration of the heavier oxygen isotope?oxygen-18?in ground water generally indicates effects of evaporation on recharge water from irrigation. Wells in undeveloped areas and wells that have openings beneath a confining bed generally yield ground water that is free of the effects of irrigation seepage. Samples from these wells did not contain detectable concentrations of pesticides. The median concentrations of nitrate (as nitrogen) and dissolved solids in samples from wells in undeveloped areas were 1.7 milligrams per liter and 257 milligrams per liter, respectively. The median concentrations of nitrate (as nitrogen) and dissolved solids in samples from wells that yield water from below confining beds were 2.0 and 747 milligrams per liter, respectively.

Monitoring the decontamination of a site polluted by DNAPLs

NASA Astrophysics Data System (ADS)

Audí-Miró, C.; Espinola, R.; Torrentó, C.; Otero, N.; Rossi, A.; Palau, J.; Soler, A.

2012-04-01

The aim of this study is to monitor the decontamination of a site polluted by DNAPLs coming from an automotive industry. The contamination was caused by the poor management of the waste generated by the industrial activity, which was discharged into a seepage pit. As a result, soil contamination was produced in the seepage pit area and a plume of DNAPLs-contaminated groundwater was generated. To recover the original environmental quality, a dual action was proposed: in the first place, the removal of the source of contamination and in the second one, the treatment of the DNAPLs plume. The elimination of the source of contamination consisted on a selective excavation of the seepage pit and an offsite management of the contaminated land. To restore the groundwater quality, a passive treatment system using a permeable reactive barrier (PRB) of zero valent iron (ZVI) was implemented. In order to determine the efficiency of the remediation actions, a chemical, isotopic and hydrogeological control of the main solvents detected in groundwater (perchloroethylene -PCE-, trichloroethene -TCE- and cis-dichloroethylene -cis-DCE-) has been established. Results show a decrease in PCE concentration that has been attributed to the removal of the source more than to a degradation process. However, the presence of PCE by-products, TCE and cis-DCE, might indicate a possible PCE biotic degradation. δ13CPCE values analyzed upstream and downstream of the barrier don't show isotopic changes associated to the PRB (values are around -20‰ in all the sampling points). TCE might have experienced a natural advanced degradation process according to the high concentration of cis-DCE found prior the installation of the PRB and the isotopic enrichment in δ13CTCE in some specific areas of the plume (-19.9‰ in the source and -16‰ before the barrier). Slight isotopic changes have been observed in the water flow in a far distance after the barrier (-15.4‰). δ13Ccis-DCE experienced an

Probabilistic Health Risk Assessment of Chemical Mixtures: Importance of Travel Times and Connectivity

NASA Astrophysics Data System (ADS)

Henri, Christopher V.; Fernàndez-Garcia, Daniel; de Barros, Felipe P. J.

2014-05-01

Subsurface contamination cases giving rise to groundwater pollutions are extensively found in all industrialized countries. Under this pressure, risk assessment methods play an important role in population protection by (1) quantifying the potential impact on human health of an aquifer contamination and (2) helping and driving decisions of groundwater-resource managers. Many reactive components such as chlorinated solvents or nitrates potentially experience attenuation processes under common geochemical conditions. This represents an attractive and extensively used remediation solution but leads often to the production of by-products before to reach a harmless chemical form. This renders mixtures of contaminants a common issue for groundwater resources managers. In this case, the threat posed by these contaminants to human health at a given sensitive location greatly depends on the competition between reactive and advective-dispersive characteristic times. However, hydraulic properties of the aquifer are known to be spatially variable, which can lead to the formation of preferential flow channels and fast contamination pathways. Therefore, the uncertainty on the spatial distribution of the aquifer properties controlling the plume travel time may then play a particular role in the human health risk assessment of chemical mixtures. We investigate here the risk related to a multispecies system in response to different degrees of heterogeneity of the hydraulic conductivity (K or Y =ln(K)). This work focuses on a Perchloroethylene (PCE) contamination problem followed by the sequential first-order production/biodegradation of its daughter species Trichloroethylene (TCE), Dichloroethylene (DCE) and Vinyl Chlorine (VC). For this specific case, VC is known to be a highly toxic contaminant. By performing numerical experiments, we evaluate transport through three-dimensional mildly (σY 2=1.0) and highly (σY 2=4.0) heterogeneous aquifers. Uncertainty on the hydraulic

Ground-water-quality assessment of the Central Oklahoma aquifer, Oklahoma; hydrologic, water-quality, and quality-assurance data 1987-90

USGS Publications Warehouse

Ferree, D.M.; Christenson, S.C.; Rea, A.H.; Mesander, B.A.

1992-01-01

, ranging from below the reporting level to concentrations over the Maximum Contaminant Levels for several constituents (arsenic, barium, cadmium, chromium, lead, and selenium). Radionuclide activities also were highly variable. Gross alpha radioactivity ranged from 0.1 to 210 picocuries per liter as 230thorium. Of the wells sampled, 20 percent exceeded the proposed Maximum Contaminant Level of 15 picocuries per liter for gross alpha radioactivity. Organic constituents were detected in 39 percent of the 170 wells sampled for organic constituents; in most cases concentrations were at or near the laboratory minimum reporting levels. Ten of the wells sampled for organic constituents had one or more constituents (chlordane, dieldrin, heptachlor epoxide, trichloroethylene, 1,1-dichloroethylene, 1,1,1-trichloroethane) at concentrations equal to or greater than the Maximum Contaminant Level or acceptable concentrations as suggested in the Environmental Protection Agency's Health Advisory Summaries. Quality-assurance sampling included duplicate samples, repeated samples, blanks, spikes, and blind samples. These samples proved to be essential in evaluating the accuracy of the data, particularly in the case of volatile organic constituents.

Post-remediation biomonitoring of pesticides and other contaminants in marine waters and sediment near the United Heckathorn Superfund Site, Richmond, California

DOE Office of Scientific and Technical Information (OSTI.GOV)

LD Antrim; NP Kohn

Marine sediment remediation at the United Heckathorn Superfund Site was completed in April 1997. Water and mussel tissues were sampled in February 1999 from four stations near Lauritzen Canal in Richmond, California, for Year 2 of post-remediation monitoring of marine areas near the United Heckathorn Site. Dieldrin and dichlorodiphenyl trichloroethane (DDT) were analyzed in water samples, tissue samples from resident mussels, and tissue samples from transplanted mussels deployed for 4 months. Concentrations of dieldrin and total DDT in water and total DDT in tissue were compared with Year 1 of post-remediation monitoring, and with preremediation data from the California Statemore » Mussel Watch program (tissues) and the Ecological Risk Assessment for the United Heckathorn Superfund Site (tissues and water). Mussel tissues were also analyzed for polychlorinated biphenyls (PCB), which were detected in sediment samples. Chlorinated pesticide concentrations in water samples were similar to preremediation levels and did not meet remediation goals. Mean dieidrin concentrations in water ranged from 0.62 rig/L to 12.5 ng/L and were higher than the remediation goal (0.14 ng/L) at all stations. Mean total DDT concentrations in water ranged from 14.4 ng/L to 62.3 ng/L and exceeded the remediation goal (0.59 ng/L) at all stations. The highest concentrations of both pesticides were found at the Lauritzen Canal/End station. Despite exceedence of the remediation goals, chlorinated pesticide concentrations in Lauritzen Canal water samples were notably lower in 1999 than in 1998. Tissue samples from biomonitoring organisms (mussels) provide an indication of the longer-term integrated exposure to contaminants in the water column, which overcomes the limitations of grab samples of water. Biomonitoring results indicated that the bioavailability of chlorinated pesticides has been reduced from preremediation levels both in the dredged area and throughout Richmond Harbor. Total DDT and

Long Term Leaching of Chlorinated Solvents from Source Zones in Low Permeability Settings with Fractures

NASA Astrophysics Data System (ADS)

Bjerg, P. L.; Chambon, J.; Troldborg, M.; Binning, P. J.; Broholm, M. M.; Lemming, G.; Damgaard, I.

2008-12-01

Groundwater contamination by chlorinated solvents, such as perchloroethylene (PCE), often occurs via leaching from complex sources located in low permeability sediments such as clayey tills overlying aquifers. Clayey tills are mostly fractured, and contamination migrating through the fractures spreads to the low permeability matrix by diffusion. This results in a long term source of contamination due to back-diffusion. Leaching from such sources is further complicated by microbial degradation under anaerobic conditions to sequentially form the daughter products trichloroethylene, cis-dichloroethylene (cis-DCE), vinyl chloride (VC) and ethene. This process can be enhanced by addition of electron donors and/or bioaugmentation and is termed Enhanced Reductive Dechlorination (ERD). This work aims to improve our understanding of the physical, chemical and microbial processes governing source behaviour under natural and enhanced conditions. That understanding is applied to risk assessment, and to determine the relationship and time frames of source clean up and plume response. To meet that aim, field and laboratory observations are coupled to state of the art models incorporating new insights of contaminant behaviour. The long term leaching of chlorinated ethenes from clay aquitards is currently being monitored at a number of Danish sites. The observed data is simulated using a coupled fracture flow and clay matrix diffusion model. Sequential degradation is represented by modified Monod kinetics accounting for competitive inhibition between the chlorinated ethenes. The model is constructed using Comsol Multiphysics, a generic finite- element partial differential equation solver. The model is applied at two well characterised field sites with respect to hydrogeology, fracture network, contaminant distribution and microbial processes (lab and field experiments). At the study sites (Sortebrovej and Vadsbyvej), the source areas are situated in a clayey till with fractures

Volatile organic compound data from three karst springs in middle Tennessee, February 2000 to May 2001

USGS Publications Warehouse

Williams, Shannon D.; Farmer, James

2003-01-01

The U.S. Geological Survey (USGS), in cooperation with the Tennessee Department of Environment and Conservation, Division of Superfund, collected discharge, rainfall, continuous water-quality (temperature, dissolved oxygen, specific conductance, and pH), and volatile organic compound (VOC) data from three karst springs in Middle Tennessee from February 2000 to May 2001. Continuous monitoring data indicated that each spring responds differently to storms. Water quality and discharge at Wilson Spring, which is located in the Central Basin karst region of Tennessee, changed rapidly after rainfall. Water quality and discharge also varied at Cascade Spring; however, changes did not occur as frequently or as quickly as changes at Wilson Spring. Water quality and discharge at Big Spring at Rutledge Falls changed little in response to storms. Cascade Spring and Big Spring at Rutledge Falls are located in similar hydrogeologic settings on the escarpment of the Highland Rim. Nonisokinetic dip-sampling methods were used to collect VOC samples from the springs during base-flow conditions. During selected storms, automatic samplers were used to collect water samples at Cascade Spring and Wilson Spring. Water samples were collected as frequently as every 15 minutes at the beginning of a storm, and sampling intervals were gradually increased following a storm. VOC samples were analyzed using a portable gas chromatograph (GC). VOC samples were collected from Wilson, Cascade, and Big Springs during 600, 199, and 55 sampling times, respectively, from February 2000 to May 2001. Chloroform concentrations detected at Wilson Spring ranged from 0.073 to 34 mg/L (milligrams per liter). Chloroform concentrations changed during most storms; the greatest change detected was during the first storm in fall 2000, when chloroform concentrations increased from about 0.5 to about 34 mg/L. Concentrations of cis-1,2-dichloroethylene (cis-1,2-DCE) detected at Cascade Spring ranged from 0.30 to 1.8 ?g

I{ Relationship between source clean up and mass flux of chlorinated solvents in low permeability settings with fractures}

NASA Astrophysics Data System (ADS)

Bjerg, P. L.; Chambon, J. C.; Christiansen, C. M.; Broholm, M. M.; Binning, P. J.

2009-04-01

Groundwater contamination by chlorinated solvents, such as perchloroethylene (PCE), often occurs via leaching from complex sources located in low permeability sediments such as clayey tills overlying aquifers. Clayey tills are mostly fractured, and contamination migrating through the fractures spreads to the low permeability matrix by diffusion. This results in a long term source of contamination due to back-diffusion. Leaching from such sources is further complicated by microbial degradation under anaerobic conditions to sequentially form the daughter products trichloroethylene, cis-dichloroethylene (cis-DCE), vinyl chloride (VC) and ethene. This process can be enhanced by addition of electron donors and/or bioaugmentation and is termed Enhanced Reductive Dechlorination (ERD). This work aims to improve our understanding of the physical, chemical and microbial processes governing source behaviour under natural and enhanced conditions. That understanding is applied to risk assessment, and to determine the relationship and time frames of source clean up and plume response. To meet that aim, field and laboratory observations are coupled to state of the art models incorporating new insights of contaminant behaviour. The long term leaching of chlorinated ethenes from clay aquitards is currently being monitored at a number of Danish sites. The observed data is simulated using a coupled fracture flow and clay matrix diffusion model. Sequential degradation is represented by modified Monod kinetics accounting for competitive inhibition between the chlorinated ethenes. The model is constructed using Comsol Multiphysics, a generic finite- element partial differential equation solver. The model is applied at well characterised field sites with respect to hydrogeology, fracture network, contaminant distribution and microbial processes (lab and field experiments). At one of the study sites (Sortebrovej), the source areas are situated in a clayey till with fractures and

Water quality of selected rivers in the New England Coastal Basins in Maine, Massachusetts, New Hampshire, and Rhode Island, 1998-2000

USGS Publications Warehouse

Campo, Kimberly W.; Flanagan, Sarah M.; Robinson, Keith W.

2003-01-01

freshwater aquatic life. The volatile organic compounds trichloroethylene, tetrachloroethylene, and cis-1,2- dichloroethylene--all solvents and de-greasers--were detected in all water samples from both rivers. The gasoline oxygenate methyl tert-butyl ether (MTBE) and the disinfection by-product chloroform were detected in all but one water sample from the two rivers. Two water samples from the Charles River had trichloroethylene concentrations that exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level of 5 micrograms per liter for drinking water. Selected water-quality data from two NCEB rivers in the Boston metropolitan area were compared to two similarly sized intensely urban rivers in another NAWQA study area in the New York City metropolitan area and to other urban rivers sampled as part of the NAWQA Program nationally. Nutrient total nitrogen and total phosphorus concentrations and yields were less in the NECB study area than in the other study areas. In addition, the pesticides atrazine, carbaryl, diazinon, and prometon were detected less frequently and at lower concentrations in the two NECB rivers than in the New York City area streams or in the other urban NAWQA streams. Concentrations of the insecticides diazinon and carbaryl were detected more frequently and at higher concentrations in the NECB study area than in the other urban rivers sampled by NAWQA nationally. Detection frequency and concentrations of volatile organic compounds generally were higher in the two NECB streams than in the New York City area streams or in other urban NAWQA streams.

Hydrogeology of the area near the J4 test cell, Arnold Air Force Base, Tennessee

USGS Publications Warehouse

Haugh, C.J.

1996-01-01

. The occurrence, distribution, and orientation of these features has a great effect on ground-water flow to the J4 test cell. The depression caused by dewatering extends out horizontally through the aquifers along the most permeable pathways. Since the aquifers above the Chattanooga Shale are not separated by distinct confining units, areas in adjacent aquifers above and below these zones of high permeability in the Manchester aquifer are also dewatered. Conditions in all Highland Rim aquifers approximate steady-state equilibrium because ground-water withdrawal at the test cell has been continuous since the late 1960's. The average ground-water discharge from the dewatering system at the J4 test cell was 105 gallons per minute, for 1992-95. The ground-water capture areas in each aquifer extend into all or parts of landfill #2 and leaching pit #2 (IRP site 1), the main testing area (IRP site 7), and the old fire training area (IRP site 10). IRP sites 8 and 12 are outside the ground-water capture areas. Of the 35 sampled wells in the J4 area, 10 produced water samples containing chlorinated organic compounds such as 1,2-dichloroethane (1,2-DCA), 1,1-dichloroethylene (1,1-DCE), and trichloroethylene (TCE) in concentrations which exceeded the Tennessee Department of Environment and Conservation Maximum Contaminant Levels (MCL's) for public water-supply systems. The highest concentrations were detected in samples from well AEDC-274 with 45 micrograms per liter (mg/L) 1,2-DCA, 320 mg/L 1,1-DCE, and 1,200 mg/L TCE. These compounds are synthetic and do not occur naturally in the environment. A sample of the ground-water discharge from the J4 test cell also contained concentrations of these compounds that exceed MCL's. Chlorinated organic compounds, including 1,2-DCA; 1,1-DCE; and TCE also have been detected at IRP sites 1, 7, 8, nd 10. The six dewatering wells surrounding the J4 test cell penetrate the Chattanooga Shale and are open to the Highland Rim aquifer system, there

Assessment of ethylene dibromide, dibromochloropropane, other volatile organic compounds, radium isotopes, radon, and inorganic compounds in groundwater and spring water from the Crouch Branch and McQueen Branch aquifers near McBee, South Carolina, 2010-2012

USGS Publications Warehouse

Landmeyer, James E.; Campbell, Bruce G.

2014-01-01

The water-quality data collected between 2010 and 2012, in conjunction with groundwater flow pathways and historical aerial photographs of land uses near McBee, indicate an area where EDB-, DBCP-, 1,2-dichloropropane-, 1,3-dichloropropane-, and carbon disulfide-contaminated groundwater exists in the Crouch Branch aquifer in the Cedar Creek Basin and north of McBee and is most likely related to the past use of these compounds between the early 1900s and the 1980s as soil fumigants in predominately agricultural areas north of McBee. The highest EDB concentration detected (18.6 micrograms per liter) during the 3-year study was in a groundwater sample from an agricultural-supply well located north of McBee. Other VOCs, such as dichloromethane and 1,1,2-trichloroethane, also were detected in groundwater samples from this EDB-contaminated agricultural-supply well but are from unknown source(s). The fact that the agricultural area north of McBee is located in a recharge area for the Crouch Branch aquifer most likely facilitated the groundwater contamination in this area. DBCP-contaminated groundwater detected in three public-supply wells south of McBee in the deeper McQueen Branch aquifer appears to be related to past soil fumigation practices that used DBCP in agricultural areas located south of McBee. One of the three DBCP-contaminated public-supply wells also contained EDB, most likely present in groundwater due to the release of leaded gasolines that contained EDB as a fuel additive between the 1940s and 1970s. A gasoline-source of EDB, rather than a soil-fumigation source, is supported by the co-detection in groundwater from the well of 1,2-dichloroethane, a lead scavenger compound also added to leaded gasoline. Groundwater pumped from two public-supply wells located within and to the east of the McBee town limits and one domestic-supply well east of McBee was characterized by the detection of 1,1-dichloroethane, trichloroethylene, 1,1-dichloroethylene, and

Hydrogeology and water quality of a surficial aquifer underlying an urban area, Manchester, Connecticut

USGS Publications Warehouse

Mullaney, John R.; Grady, Stephen J.

1997-01-01

The quality of water along flowpaths in a surficial aquifer system in Manchester, Connecticut, was studied during 1993-95 as part of the National Water Quality Assessment program. The flowpath study examined the relations among hydrogeology, land-use patterns, and the presence of contaminants in a surficial aquifer in an urban area, and evaluated ground water as a source of contamination to surface water. A two-dimensional, finite-difference groundwater- flow model was used to estimate travel distance, which ranged from about 50 to 11,000 feet, from the source areas to the sampled observation wells. Land use, land cover, and population density were determined in the source areas delineated by the ground-water-flow simulation. Source areas to the wells contained either high- or medium-density residential areas, and population density ranged from 629 to 8,895 people per square mile. Concentrations of selected inorganic constituents, including sodium, chloride, and nitrite plus nitrate nitrogen, were higher in the flowpath study wells than in wells in undeveloped areas with similar aquifer materials. One or more of 9 volatile organic compounds were detected at 12 of 14 wells. The three most commonly detected volatile organic compounds were chloroform, methyl-tert-butyl ether, and trichloroethene. Trichloroethene was detected at concentrations greater than the maximum contaminant level for drinking water (5 micrograms per liter) in samples from one well. Four pesticides, including dichloro diphenyl dichloroethylene, dieldrin, dichloroprop, and simazine were detected at low concentrations. Concentrations of sodium and chloride were higher in samples collected from wells screened in the top of the saturated zone than in samples collected from deeper zones. Volatile organic compounds and elevated concentrations of nitrite plus nitrate as nitrogen were detected at depths of as much as 60 feet below the water table, indicating that the effects of human activities on the

Interpretation of geophysical logs, aquifer tests, and water levels in wells in and near the North Penn Area 7 Superfund site, Upper Gwynedd Township, Montgomery County, Pennsylvania, 2000-02

USGS Publications Warehouse

Senior, Lisa A.; Cinotto, Peter J.; Conger, Randall W.; Bird, Philip H.; Pracht, Karl A.

2005-01-01

high-angle fractures and bedding-plane openings throughout the depth of the boreholes. Heatpulse-flowmeter measurements under nonpumping, ambient conditions indicated that borehole flow, where detected, was in the upward direction in three of the eight wells and in the downward direction in three wells. In two wells, both upward and downward flow were measured. Heatpulse-flowmeter measurements under pumping conditions were used to identify the most productive intervals in wells. Correlation of natural-gamma-ray and single-point-resistance logs indicated that bedding in the area probably strikes about 40 degrees northeast and dips from 6 to 7 degrees northwest. Aquifer intervals isolated by inflatable packers in wells were pumped to test productivity and to collect samples to determine chemical quality of water produced from the interval. Interval-isolation testing confirmed the presence of vertical hydraulic gradients indicated by heatpulse-flowmeter measurements. The specific capacities of isolated intervals ranged over two orders of magnitude, from 0.02 to more than 3.6 gallons per minute per foot. Intervals adjacent to isolated pumped intervals showed little response to pumping the isolated zone. The presence of vertical hydraulic gradients and lack of adjacent-interval response to pumping in isolated intervals indicate a limited degree of vertical hydraulic connection between the aquifer intervals tested. Concentrations of most VOC contaminants generally were highest in well-water samples from the shallowest isolated intervals, with some exceptions. Trichloroethylene, cis-1,2-dichloroethylene, and toluene were the most frequently detected VOCs, with maximum concentrations of greater than 340, 680, and greater than 590 micrograms per liter, respectively. Results of the aquifer test with multiple observation wells showed that water levels in 4 of the 14 wells declined in response to pumping. The four wells that responded to pumping are either along str

Occurrence of Selected Organic Compounds in Groundwater Used for Public Supply in the Plio-Pleistocene Deposits in East-Central Nebraska and the Dawson and Denver Aquifers near Denver, Colorado, 2002-2004

USGS Publications Warehouse

Bails, Jeffrey B.; Dietsch, Benjamin J.; Landon, Matthew K.; Paschke, Suzanne S.

2009-01-01

), which were detected in 9 of the 15 wells (60 percent of the samples). The second most frequently detected organic compound was tetrachloroethylene, detected in 4 of the 15 wells (27 percent of the samples), followed by chloroform, trichloroethylene, and 2-hydroxyatrazine (2-hydroxy-4-isopropylamino-6-ethylamino-s-triazine, or OIET), present in 3 of the 15 wells (20 percent of the samples). The pesticide compounds deisopropylatrazine (2-chloro-6-ethylamino-4-amino-s-triazine, or CEAT), metolachlor, and simazine and the volatile organic compound cis-1,2-dichloroethylene were detected in 2 of the 15 wells, and the compounds diuron and 1,2-dichloroethane were detected in only 1 of the 15 wells during the first-year sampling. Most detections of these compounds were at or near the minimum reporting levels, and none were greater than their regulatory maximum contaminant level. There were few detections of organic compounds during the first year of sampling groundwater wells in the South Platte study area. The compounds atrazine, deethylatrazine, picloram, tetrachloroethylene, methyl-tert-butyl-ether (MTBE), tris(2-butoxyethyl)phosphate, and bromoform were detected only once in all the samples from the 12 wells. Most detections of these compounds were at or near the minimum reporting levels, and none were greater than their regulatory maximum contaminant level. Second-year sampling, which included the addition of paired source- and finished-water samples, was completed at two sites in the High Plains study area. Source-water samples from the second-year sampling had detections of atrazine and deethylatrazine; at one site deisopropylatrazine and chloroform also were detected. The finished-water samples, which represent the source water after blending with water from other wells and treatment, indicated a decrease in the concentrations of the pesticides at one site, whereas concentrations remained nearly constant at a second site. The trihalomethanes (THMs or disinfec

Assessment of Hyporheic Zone, Flood-Plain, Soil-Gas, Soil, and Surface-Water Contamination at the McCoys Creek Chemical Training Area, Fort Gordon, Georgia, 2009-2010

USGS Publications Warehouse

Guimaraes, Wladmir B.; Falls, W. Fred; Caldwell, Andral W.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

2011-01-01

The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the hyporheic zone, flood plain, soil gas, soil, and surface water for contaminants at the McCoys Creek Chemical Training Area (MCTA) at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic contaminants in the hyporheic zone, flood plain, soil gas, and surface water. In addition, the organic contaminant assessment included the analysis of organic compounds classified as explosives and chemical agents in selected areas. Inorganic contaminants were assessed in soil and surface-water samples. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Ten passive samplers were deployed in the hyporheic zone and flood plain, and total petroleum hydrocarbons (TPH) and octane were detected above the method detection level in every sampler. Other organic compounds detected above the method detection level in the hyporheic zone and flood-plain samplers were trichloroethylene, and cis- and trans- 1, 2-dichloroethylene. One trip blank detected TPH below the method detection level but above the nondetection level. The concentrations of TPH in the samplers were many times greater than the concentrations detected in the blank; therefore, all other TPH concentrations detected are considered to represent environmental conditions. Seventy-one soil-gas samplers were deployed in a grid pattern across the MCTA. Three trip blanks and three method blanks were used and not deployed, and TPH was detected above the method detection level in two trip blanks and one method blank. Detection of TPH was observed at all 71 samplers, but because TPH was detected in the trip and method blanks, TPH was

Hydrogeology, water chemistry, and transport processes in the zone of contribution of a public-supply well in Albuquerque, New Mexico, 2007-9

USGS Publications Warehouse

Bexfield, Laura M.; Jurgens, Bryant C.; Crilley, Dianna M.; Christenson, Scott C.

2012-01-01

(TCE) and cis-1,2-dichloroethylene had been detected in the SSW, and several of these wells may have become contaminated at least partly because of enhanced vertical migration associated with the pumping of and (or) direct migration down deep well bores. Except for TCE in the sample from a shallow monitoring well, all detections of VOCs were at concentrations below Maximum Contaminant Levels (MCLs) set by the U.S. Environmental Protection Agency. Concentrations of all VOCs detected in the supply wells were less than one-tenth of the corresponding MCLs. However, the presence of VOCs in all but deep groundwater, including the detection of chloroform (a chlorination byproduct) in several shallow wells, indicates that groundwater in the study area commonly is affected by human activities, even to substantial depths. The only natural contaminant detected at concentrations near or above its MCL was arsenic, which has been detected at elevated concentrations across broad areas of the MRGB. Concentrations of arsenic, present primarily as arsenate, exceeded the MCL of 10 micrograms per liter (μg/L) in water from the two deep wells (one of which had the highest concentration, 35 μg/L), from one intermediate well, and from two supply wells, including the SSW. Water-quality and solid-phase data from this study are consistent with elevated arsenic concentrations in groundwater being related to pH-dependent desorption of arsenic from ferric oxyhydroxides in sediments in deep parts of the aquifer. Concentrations of nitrate ranged between 1.3 and 5.4 milligrams per liter (mg/L) in water from shallow wells screened across the water table, but were less than 0.9 mg/L in water from all but one deeper well. Nitrogen isotopes and chloride/bromide ratios for shallow wells were consistent with natural soil nitrogen. Nitrate concentrations and nitrogen isotopes indicated that denitrification is occurring at intermediate aquifer depths, and that the progress of the denitrification reaction

Davis Pond freshwater prediversion biomonitoring study: freshwater fisheries and eagles

USGS Publications Warehouse

Jenkins, Jill A.; Bourgeois, E. Beth; Jeske, Clint W.

2008-01-01

assessed possible influx of contaminants with the freshwater diversion, contaminant levels in fishes and bivalves in this study were generally lower, yet three nontoxic inorganic elements in Davis Pond fish samples exhibited ranges of concentrations that were more than two times higher than did those from Caernarvon. Levels in bivalves were different between diversions but about equal in the numbers of trace elements showing high levels per location. Contaminant values were compared to those listed in various literature and agency sources, both regional and national, including the National Contaminant Biomonitoring Program (NCBP), in which the 85th percentile and above represents what is considered to be an elevated contaminant concentration and cause for concern. Generally, bivalves were at the high end of their ranges for both organic and inorganic contaminants. In this study, OCs were detectable in 67 percent of fish from the Mississippi River site, ranging from 0.15 to 1.09 μg/g wet weight (ww) or fresh weight (fw), and in 11 percent of the fish from the marsh sites, ranging from 0.06 to 0.612 μg/g ww. Bivalves from the Mississippi River had OC levels of 0.096 μg/g ww, whereas none were detectable in bivalves at the marsh sites. In this study, p,p’-dichlorodiphenyldichloroethylene (p,p’-DDE) (a biodegradation product of DDT [dichlorodiphenyl trichloroethane]) and total PCBs were the most frequently detected OCs and were primarily from the Mississippi River. For total OC content, using adjusted least squares means, some significant interactions were noted between fish species and sites. PAHs were detected in aquatic animals at all sites (range of 0.017–17.534 μg/g ww), as were AHs (range of 0.423–4.549 μg/g ww); the highest levels of PAHs and AHs were found in bivalves from the Mississippi River. When analysis of variance (α = 0.05) was performed with data from aquatic animals, there were only two significant relationships between PAHs, AHs, and OCs