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Sample records for biphenyl mixture aroclor

  1. Human receptor activation by aroclor 1260, a polychlorinated biphenyl mixture.

    Science.gov (United States)

    Wahlang, Banrida; Falkner, K Cameron; Clair, Heather B; Al-Eryani, Laila; Prough, Russell A; States, J Christopher; Coslo, Denise M; Omiecinski, Curtis J; Cave, Matthew C

    2014-08-01

    Polychlorinated biphenyls (PCBs) are persistent environmental toxicants, present in 100% of U.S. adults and dose-dependently associated with obesity and non-alcoholic fatty liver disease (NAFLD). PCBs are predicted to interact with receptors previously implicated in xenobiotic/energy metabolism and NAFLD. These receptors include the aryl hydrocarbon receptor (AhR), pregnane xenobiotic receptor (PXR), constitutive androstane receptor (CAR), peroxisome proliferator-activated receptors (PPARs), liver-X-receptor (LXRα), and farnesoid-X-receptor (FXR). This study evaluates Aroclor 1260, a PCB mixture with congener composition mimicking that of human adipose tissue, and selected congeners, as potential ligands for these receptors utilizing human hepatoma-derived (HepG2) and primate-derived (COS-1) cell lines, and primary human hepatocytes. Aroclor 1260 (20 μg/ml) activated AhR, and PCB 126, a minor component, was a potent inducer. Aroclor 1260 activated PXR in a simple concentration-dependent manner at concentrations ≥10 μg/ml. Among the congeners tested, PCBs 138, 149, 151, 174, 183, 187, and 196 activated PXR. Aroclor 1260 activated CAR2 and CAR3 variants at lower concentrations and antagonize CAR2 activation by the CAR agonist, CITCO, at higher concentrations (≥20 μg/ml). Additionally, Aroclor 1260 induced CYP2B6 in primary hepatocytes. At subtoxic doses, Aroclor 1260 did not activate LXR or FXR and had no effect on LXR- or FXR-dependent induction by the agonists T0901317 or GW4064, respectively. Aroclor 1260 (20 μg/ml) suppressed PPARα activation by the agonist nafenopin, although none of the congeners tested demonstrated significant inhibition. The results suggest that Aroclor 1260 is a human AhR, PXR and CAR3 agonist, a mixed agonist/antagonist for CAR2, and an antagonist for human PPARα. PMID:24812009

  2. Human Receptor Activation by Aroclor 1260, a Polychlorinated Biphenyl Mixture

    OpenAIRE

    Wahlang, Banrida; Falkner, K. Cameron; Clair, Heather B.; Al-Eryani, Laila; Prough, Russell A.; States, J. Christopher; Coslo, Denise M.; Omiecinski, Curtis J.; Cave, Matthew C.

    2014-01-01

    Polychlorinated biphenyls (PCBs) are persistent environmental toxicants, present in 100% of U.S. adults and dose-dependently associated with obesity and non-alcoholic fatty liver disease (NAFLD). PCBs are predicted to interact with receptors previously implicated in xenobiotic/energy metabolism and NAFLD. These receptors include the aryl hydrocarbon receptor (AhR), pregnane xenobiotic receptor (PXR), constitutive androstane receptor (CAR), peroxisome proliferator-activated receptors (PPARs), ...

  3. Stimulatory effects of a microbially dechlorinated polychlorinated biphenyl (PCB) mixture on rat uterine contraction in vitro

    OpenAIRE

    Tsuneta, Taeko; Loch-Caruso, Rita; Quensen, John F.; Boyd, Stephen A.; Hanna, Mona; Grindatti, Carmen

    2008-01-01

    Microbially mediated reductive dechlorination has been advocated as the first part of a two-stage (anaerobic/aerobic) biotreatment process for polychlorinated biphenyls (PCBs) in sediments, and is generally viewed as a detoxication process. However, previous studies suggest that microbial dechlorination increases ability to stimulate uterine contractions compared with the original PCB mixtures. Here, we investigate the composition and uterotonic activity of the commercial PCB mixture Aroclor ...

  4. Effect of gestational and lactational exposure to the polychlorinated biphenyl mixture aroclor 1254 on learning and memory and hippocampus in rat offspring%孕哺期接触多氯联苯对大鼠子代学习记忆及海马神经元的影响

    Institute of Scientific and Technical Information of China (English)

    刘承芸; 白文琳; 陈建平; 牛侨

    2015-01-01

    Objective To explore the effect of polychlorinated biphenyls (PCBs) on the learning and memory of gestational and lactational exposure to polychlorinated biphenyls in rats offspring.Methods The PCB mixture (A1254,0,5,10,20 mg/kg body weight) was administered to pregnant wistar rats every 3 days by gavage from gestational day (GD) 5 to postnatal day (PND) 20.To assess the effects on offspring following such exposure,Morris water maze test was performed to assess the learning and memory ability.Calcium concentration was assayed in hippocampus and the ultramicro structure was observed.Results After training for four days,the escaping latency in every group decreased significantly compared with the first day,especially the control group,the results in the fourth day decreased significantly with the early three days(P<0.05).The offsprings of the 10 and 20 mg/kg had prolonged time of passing the aim target ((5.23± 1.16) s,(7.90±3.21) s,(11.74±6.56) s and (20.83± 8.38) s ; P<0.05),decreased number of crossing platform ((4.14± 1.21),(3.00± 1.32),(2.65± 1.13),(2.42± 1.31) ; P<0.05) and swimming time in the target area ((40.14±7.14)s,(33.76±5.58)s,(32.45±6.00)s and (30.63±5.10) s; P<0.05)compared with those of the rats of control and 5 mg/kg groups.The calcium concentration increased ((121.16± 12.23) nM,(141.27±24.66) nM,(163.32±29.75) nM,(261.46±27.79) nM) and the ultramicro structure in hippocampus changed obviously in the high exposure group.Conclusion Gestational and lactational exposure to aroclor 1254 in rats could affect the leaming and memory ability of offsprings.%目的 探讨孕哺期接触多氯联苯对仔鼠学习记忆的影响及生理机制.方法 成年Wistar大鼠受孕后用不同浓度的aroclor1254染毒,仔鼠出生1个月后进行水迷宫实验,分离海马细胞测定细胞内游离钙离子浓度,透射电镜观察海马神经元的超微结构.结果 各组仔鼠经过4d训练后潜伏期与第1

  5. Reproductive dysfunction in rhesus monkeys exposed to low levels of polychlorinated biphenyls (Aroclor 1248)

    Energy Technology Data Exchange (ETDEWEB)

    Barsotti, D.A.; Marlar, R.J.; Allen, J.R.

    1976-01-01

    Eighteen female and four male adult Rhesus monkeys were fed the polychlorinated biphenyl (PCB) Aroclor 1248 at levels of either 2.5 or 5.0 ppM in the diet. These levels are equal to, and 50% of, the concentration allowed in certain foods destined for human consumption. After consuming these diets for 2 months, some of the females developed acne, alopecia, erythema and swelling of the eyelids, and by 6 months all females exhibited these changes to some degree. Modifications in serum lipids developed gradually, with a trend towards hypocholesterolaemia, hypolipidaemia and decreased serum triglycerides. In addition there was a shift in the plasma albumin/globulin ratio and an increase in serum glutamic-pyruvic transaminase activity. Analysis of subcutaneous fat showed an accumulation of the PCB isomers in the adipose tissue. The concentrations in this tissue reached a plateau, after which only slight variations were observed. Within 4 months, menstrual cycles were altered: menostaxis and menorrhagia occurred frequently and at times amenorrhoea was apparent. The ability of the animals to maintain pregnancy was impaired, as indicated by frequent resorptions and abortions. When infants were born they were small, and the transplacental movement of PCBs was evident from analyses of skin biopsies of neonates and of autopsy tissue from one stillborn. Moreover, additional accumulation of PCBs occurred in infants during breast feeding. All males fed 5.0 ppM PCB exhibited only slight periorbital oedema and erythema after 14 months on the diet and showed no alterations in their breeding capacities. The data presented indicate that long-term, low-level exposure of female non-human primates to PCBs can affect many important biological parameters.

  6. Mucinous gastric hyperplasia in a colony of rhesus monkeys (Macaca mulatta) induced by polychlorinated biphenyl (Aroclor 1254)

    Energy Technology Data Exchange (ETDEWEB)

    Geistfeld, J.G.; Bond, M.G.; Bullock, B.C.; Varian, M.C.

    1982-02-01

    Since 1971, 45 of 259 male rhesus monkeys housed in a primate building have died of a chronic and progressive disease characterized by diarrhea, dehydration, weakness, gingivitis, emaciation, and alopecia. The principal necropsy finding in these monkeys, and in eight others killed for experimental purposes, was hypertrophic and hyperplastic mucinous gastropathy involving both the mucosa and submucosa. The toxic agent involved was identified as the polychlorinated biphenyl (PCB), Aroclor 1254. The suspected source of the toxic agent was a concrete sealer used during building construction.

  7. Impact of polychlorinated biphenylAroclor 1254) and vitamin C on antioxidant system of rat ventral prostate

    Institute of Scientific and Technical Information of China (English)

    M.Sridhar; P.Venkataraman; S.Dhanammal; A.Arunkumar; M.M.Aruldhas; N.Srinivasan; J.Arunakaran

    2004-01-01

    Aim:To evaluate the effect of polychlorinated biphenyls (PCB) and vitamin C on ventral prostatic antioxidant system in adult male rats.Methods:A group of 20 adult male rats were administered ip Aroclor 1254 in corn oil at a dose of 2 mg.kg-1·day-1 for 30 days.Ten control rats were administered only the vehicle.After 30 days the treated rats were divided at random into 2 sub-groups of 10 animals each.One sub-group received vitamin C at a dose of 500 mg.kg-1·day-1 for 10 days.The other group was maintained as Aroclor 1254 control.Twenty-four hours after the last treatment the rats were killed by decapitation.Ventral prostatic homogenate was prepared and used for the estimation of enzymatic antioxidants,including superoxide dismutase (SOD),catalase (CAT) and glutathione-S-transferase (GST) and hydrogen peroxide (H2O2),lipid peroxidation (LPO) and prostatic acid phosphatase.The serum levels of total T3,total T4,TSH,testosterone and estradiol were also assayed.Results:The body weight and ventral prostatic weight were reduced in PCB treated rats.The activities of SOD,CAT,GST and acid phosphatase were decreased while the levels of H2O2 and lipid peroxidation were increased in the ventral prostate of PCB treated rats.Administration of vitamin C restored these parameters.Serum levels of thyroid hormones,estradiol and testosteron ewere decreased in PCB treated animals.Administration of vitamin C restored the thyroid hormone levels.Conclusion:PCB induces oxidative stress and decreases the antioxidant enzymes in the ventral prostate of adult male rats;the effects could be reversed by the administration of vitamin C.(Asian J Androl 2004 Mar;6:19-22)

  8. Biochemical effects of an environmental chlorofen mixture in comparison with aroclor 1254 in rats

    Energy Technology Data Exchange (ETDEWEB)

    Kania-Korwel, I.; Ludewig, G.; Robertson, L.W.; Lehmler, H.J. [Dept. of Occupational and Environmental Health, Univ. of Iowa, Iowa City (United States); Hornbuckle, K.C.; Peck, A. [Dept. of Civil and Environmental Engineering, Univ. of Iowa, Iowa City (United States); Espandiari, P.; C. Gary Gairola [Graduate Center for Toxicology, Univ. of Kentucky, Lexington (United States); Sulkowski, W.W. [Dept. of Environmental Chemistry and Technology, Univ. of Silesia, Katowice (Poland)

    2004-09-15

    To our knowledge no in vivo mammalian toxicity studies with Chlorofen or environmental mixtures from Chlorofen contaminated sites have been performed. The present study investigates the biological effects in male rats of a soil-extract from a highly contaminated soil from the Chlorofen manufacturing site. The congener profile of this soil extract is very similar to Chlorofen although some lower chlorinated congeners are present, probably because of biodegradation or atmospheric deposition. The biological effect was compared with Aroclor 1254. The total PCB levels as well as the PCB congener profile in the liver were also determined to allow a better understanding of the effects of the two different mixtures on relevant liver enzymes.

  9. Effects of Aroclor 1254 on in vivo oocyte maturation in the mouse.

    Directory of Open Access Journals (Sweden)

    ShuZhen Liu

    Full Text Available Polychlorinated biphenyls (PCBs are stable, lipophilic compounds that accumulate in the environment and in the food chain. Though some studies provided evidence that PCBs had adverse effects on reproductive function, most of these results were from in vitro models. Therefore we investigated the effect of Aroclor 1254 (a commercial PCBs mixture treatments on in vivo maturation and developmental potential of mouse oocytes. In the present study, female ICR mice were treated with different doses (12.5, 25 and 50 mg/kg of Aroclor 1254 (a commercial PCB mixture once every 72 hours by intraperitoneal injection for 9 days. After three treatments of Aroclor 1254, the mice were superovulated to collect oocytes one day after the last exposure. The effects of Aroclor 1254 on oocyte maturation, fertilization, and preimplantation embryonic development were investigated. Immunofluorescence-stained oocytes were observed under a confocal microscope to assess the effects of Aroclor 1254 on spindle morphology. Parthenogenic activation and the incidence of cumulus apoptosis in cumulus-oocyte complexes were observed as well. Oocytes exposed to different doses of Aroclor 1254 in vivo were associated with a significant decrease in outgrowth potential, abnormal spindle configurations, and the inhibition of parthenogenetic activation of ovulated oocytes. Furthermore, the incidence of apoptosis in cumulus cells was increased after exposed to Aroclor 1254. These results may provide reference for the treatment of reproductive diseases such as infertility or miscarriage caused by environmental contaminants.

  10. Subchronic Polychlorinated Biphenyl (Aroclor 1254) Exposure Produces Oxidative Damage and Neuronal Death of Ventral Midbrain Dopaminergic Systems

    OpenAIRE

    Lee, Donna W.; Notter, Sarah A.; Thiruchelvam, Mona; Dever, Daniel P.; Fitzpatrick, Richard; Kostyniak, Paul J.; Cory-Slechta, Deborah A.; Opanashuk, Lisa A.

    2011-01-01

    Recent epidemiologic studies have demonstrated a link between organochlorine and pesticide exposure to an enhanced risk for neurodegenerative disorders such as Parkinson’s disease (PD). A common biological phenomenon underlying cell injury associated with both polychlorinated biphenyl (PCB) exposure and dopaminergic neurodegeneration during aging is oxidative stress (OS). In this study, we tested the hypothesis that oral PCB exposure, via food ingestion, impairs dopamine systems in the adult ...

  11. ALTERATIONS IN BRAIN PROTEIN KINASE C ISOFORMS FOLLOWING DEVELOPMENTAL EXPOSURE TO POLYCHLORINATED BIPHENYL MIXTURE.

    Science.gov (United States)

    PCBs have been shown to alter several neurochemical end-points and are implicated in the etiology of some neurological diseases. Recent in vivo studies from our laboratory indicated that developmental exposure to a commercial PCB mixture, Aroclor 1254, caused perturbations in cal...

  12. Enzyme induction and histopathology elucidate aryl hydrocarbon receptor-mediated versus non-aryl hydrocarbon receptor-mediated effects of Aroclor 1268 in American mink (Neovison vison).

    Science.gov (United States)

    Folland, William R; Newsted, John L; Fitzgerald, Scott D; Fuchsman, Phyllis C; Bradley, Patrick W; Kern, John; Kannan, Kurunthachalam; Zwiernik, Matthew J

    2016-03-01

    Polychlorinated biphenyl (PCB) concentrations reported in preferred prey and blubber of bottlenose dolphins from the Turtle-Brunswick River estuary (Georgia, USA) suggest the potential for adverse effects. However, PCBs in Turtle-Brunswick River estuary dolphins are primarily derived from Aroclor 1268, and predicting toxic effects of Aroclor 1268 is uncertain because of the mixture's unique composition and associated physiochemical characteristics. These differences suggest that toxicity benchmarks for other PCB mixtures may not be relevant to dolphins exposed to Aroclor 1268. American mink (Neovison vison) were used as a surrogate model for cetaceans to characterize mechanisms of action associated with Aroclor 1268 exposure. Mink share similarities in phylogeny and life history with cetaceans and are characteristically sensitive to PCBs, making them an attractive surrogate species for marine mammals in ecotoxicity studies. Adult female mink and a subsequent F1 generation were exposed to Aroclor 1268 through diet, and effects on enzyme induction, histopathology, thyroid hormone regulation, hematology, organ weights, and body condition index were compared to a negative control and a 3,3',4,4',5-pentachlorobiphenyl (PCB 126)-positive control. Aroclor 1268 dietary exposure concentrations ranged from 1.8 µg/g wet weight to 29 µg/g wet weight. Anemia, hypothyroidism, and hepatomegaly were observed in mink exposed to Aroclor 1268 beyond various dietary thresholds. Cytochrome P450 induction and squamous epithelial proliferation jaw lesions were low in Aroclor 1268 treatments relative to the positive control. Differences in enzyme induction and the development of squamous epithelial proliferation jaw lesions between Aroclor 1268 treatments and the positive control, coupled with effects observed in Aroclor 1268 treatments not observed in the positive control, indicate that mechanisms additional to the aryl hydrocarbon receptor-mediated pathway are associated with

  13. Study of tritium labeling of complex mixture of polychlorinated biphenyls

    International Nuclear Information System (INIS)

    The method for tritium labeling of technical mixture (commercial mark - SOVOL, USSR) of polychlorinated biphenyls (PCBs) was developed. The influence of procedure of labeling by thermally activated tritium on the nativity of polychlorinated biphenyls (PCBs) was studied. The method of labeling by thermally activated tritium has some factors, which are able to destroy organic compounds - photodegradation, thermo-degradation and degradation caused by reaction of substitution of organic compounds hydrogen atoms by activated tritium atoms. To develop a method of labeling of every organic compound by thermally activated tritium it is necessary to determine and optimize the conditions of labeling. In our case procedure of labeling is complicated because of technical mixture of PCBs consist from more than 20 isomers, chlorinated with different degree. We studied the dependence of appearance of products of degradation PCBs from duration of labeling procedure. It was found that some part of PCBs and product of its degradation were evaporated under vacuum and were collected on the glass flask cooled by liquid nitrogen. It was found that correlation between labeled of PCBs and products of degradation did not changed with increasing time of labeling, and radiochemical yield of tritium labeled of PCBs was stable - about 15-20 %. The optimum regime of labeling was selected. It was found that purification of labeled PCBs by TLC on silica gel with hexane allows obtaining tritium-labeled PCBs purified from by-products. Thus, TLC purification seems inexpensive, fast and suitable for purification of tritium-labeled PCBs

  14. Dietary exposure to the PCB mixture aroclor 1254 may compromise osmoregulation by altering central vasopressin release

    Energy Technology Data Exchange (ETDEWEB)

    Coburn, C.G. [Environmental Toxicology, Univ. of California at Riverside, CA (United States); Gillard, E.; Curras-Collazo, M. [Cell Biology and Neuroscience, Univ. of California at Riverside, CA (United States)

    2004-09-15

    Despite the importance of systemic osmoregulation, the potential deleterious effects of persistent organochlorines, such as polychlorinated biphenyls (PCBs), on body fluid regulation has not been thoroughly investigated. In an effort to ameliorate this deficit, the current study explores the toxic effects of PCBs on osmoregulation, and in particular, on the activity of the magnocellular neuroendocrine cell (MNC) system of the hypothalamus. MNCs of the supraoptic nucleus (SON) release oxytocin (OXY) and vasopressin (VP) from terminals in the neurohypophysis in response to dehydration. The latter is released to effect water conservation in response to dehydration via its action upon the kidney and through extra-renal actions. MNCs also secrete VP from their cell bodies and dendrites locally i.e., into the extracellular space of the SON. Although it has been shown that both intranuclear and systemic release rise in response to dehydration the physiological significance of intranuclear release has not been fully elucidated. We chose to use voluntary ingestion as the route of PCB exposure since it is more reflective of natural exposure compared to ip injection. One unexpected observation that resulted from pilot studies using ip injection of PCBs was the deleterious effects of the vehicle (corn oil) resulting in pooling of lipid within the abdominal cavity, mottling of the liver, fatty liver and general discoloration of all abdominal viscera at time of sacrifice. Therefore, all work described in this series of experiments have employed voluntary ingestion of the toxin. Work described in this paper suggests that PCBs in concentrations reflecting realistic lifetime exposure levels may negatively impact homeostatic mechanisms responsible for body water balance by altering somatodendritic (intranuclear) VP secretion in response to dehydration in vivo. The downstream consequences of such influence is currently under investigation, and preliminary evidence suggests that the

  15. Effects of Aroclor 1254 on dopamine and norepinephrine concentrations in pheochromocytoma (PC-12) cells

    International Nuclear Information System (INIS)

    Pheochromocytoma (PC-12) cells synthesize, store, release and metabolize dopamine (DA) and norepinephrine (NE) in a manner analogous to that observed in the mammalian central nervous system. These cells were used to develop and validate an alternate method to animal testing to assess the effects of a complex environmental mixture of polychlorinated biphenyls (Aroclor 1254) on cellular catecholamine function. Aroclor 1254, at concentrations of 1 to 100 ppm, significantly decreased cellular catecholamine concentrations after 6 hrs. Exposure at 100 ppm for periods of less than an hr increased cellular catecholamine concentrations while longer exposure times (i.e., 1 to 24 hr) decreased cellular catecholamine concentrations. This in vitro depletion of catecholamines is similar to that seen in vivo. Thus, PC-12 cells may be useful for neurochemical evaluation of neurotoxicants with particular reference to effects on catecholaminergic systems

  16. A comprehensive approach to actual polychlorinated biphenyls environmental contamination.

    Science.gov (United States)

    Risso, F; Magherini, A; Ottonelli, M; Magi, E; Lottici, S; Maggiolo, S; Garbarino, M; Narizzano, R

    2016-05-01

    Worldwide polychlorinated biphenyls (PCBs) pollution is due to complex mixtures with high number of congeners, making the determination of total PCBs in the environment an open challenge. Because the bulk of PCBs production was made of Aroclor mixtures, this analysis is usually faced by the empirical mixture identification via visual inspection of the chromatogram. However, the identification reliability is questionable, as patterns in real samples are strongly affected by the frequent occurrence of more than one mixture. Our approach is based on the determination of a limited number of congeners chosen to enable objective criteria for Aroclor identification, summing up the advantages of congener-specific analysis with the ones of total PCBs determination. A quantitative relationship is established between congeners and any single mixture, or mixtures combination, leading to the identification of the actual contamination composition. The approach, due to its generality, allows the use of different sets of congeners and any technical mixture, including the non-Aroclor ones. The results confirm that PCB environmental pollution in northern Italy is based on Aroclor. Our methodology represents an important tool to understand the source and fate of the PCBs contamination.

  17. POLYCHLORINATED BIPHENYL MIXTURES (AROCLORS) INHIBIT LPS-INDUCED MURINE B-LYMPHOCYTE PROLIFERATION IN VITRO. (R826687)

    Science.gov (United States)

    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...

  18. Growth and reproductive effects from dietary exposure to Aroclor 1268 in mink (Neovison vison), a surrogate model for marine mammals.

    Science.gov (United States)

    Folland, William R; Newsted, John L; Fitzgerald, Scott D; Fuchsman, Phyllis C; Bradley, Patrick W; Kern, John; Kannan, Kurunthachalam; Remington, Richard E; Zwiernik, Matthew J

    2016-03-01

    Polychlorinated biphenyls (PCBs) from the commercial mixture Aroclor 1268 were historically released into the Turtle-Brunswick River estuary (southeastern Georgia, USA) from industrial operations. Sum PCBs (ΣPCBs) in blubber samples from Turtle-Brunswick River estuary bottlenose dolphins (Tursiops truncatus) have been reported at concentrations more than 10-fold higher than those observed in dolphins from adjacent regional estuaries. Given that toxicity data specific to Aroclor 1268 and applicable to marine mammals are limited, predicting the toxic effects of Aroclor 1268 in dolphins is uncertain, particularly because of its unique congener profile and associated physiochemical characteristics compared with other PCB mixtures. American mink (Neovison vison) were chosen as a surrogate model for cetaceans to develop marine mammalian PCB toxicity benchmarks. Mink are a suitable surrogate species for cetaceans in toxicity studies because of similarities in diet and taxonomic class, and a characteristic sensitivity to PCBs provides a potential safety factor when using mink toxicology data for cross-species extrapolations. Effects of dietary exposure to Aroclor 1268 on reproduction, growth, and mortality in mink were compared with both a negative control and a positive control (3,3',4,4',5-pentachlorobiphenyl, PCB 126). Aroclor 1268 dietary ΣPCB concentrations ranged from 1.8 µg/g feed wet weight to 29 µg/g feed wet weight. Whelp success was unaffected by Aroclor 1268 exposure at any level. Treatment mean litter size, kit growth, and kit survival were adversely affected relative to the negative control at dietary ΣPCB concentrations of 10.6 µg/g feed wet weight and greater. PMID:26313468

  19. In Vitro Exposure of Harbor Seal Immune Cells to Aroclor 1260 Alters Phocine Distemper Virus Replication.

    Science.gov (United States)

    Bogomolni, Andrea; Frasca, Salvatore; Levin, Milton; Matassa, Keith; Nielsen, Ole; Waring, Gordon; De Guise, Sylvain

    2016-01-01

    In the last 30 years, several large-scale marine mammal mortality events have occurred, often in close association with highly polluted regions, leading to suspicions that contaminant-induced immunosuppression contributed to these epizootics. Some of these recent events also identified morbillivirus as a cause of or contributor to death. The role of contaminant exposures regarding morbillivirus mortality is still unclear. The results of this study aimed to address the potential for a mixture of polychlorinated biphenyls (PCBs), specifically Aroclor 1260, to alter harbor seal T-lymphocyte proliferation and to assess if exposure resulted in increased likelihood of phocine distemper virus (PDV USA 2006) to infect susceptible seals in an in vitro system. Exposure of peripheral blood mononuclear cells to Aroclor 1260 did not significantly alter lymphocyte proliferation (1, 5, 10, and 20 ppm). However, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR), lymphocytes exposed to 20 ppm Aroclor 1260 exhibited a significant decrease in PDV replication at day 7 and a significant increase at day 11 compared with unexposed control cells. Similar and significant differences were apparent on exposure to Aroclor 1260 in monocytes and supernatant. The results here indicate that in harbor seals, Aroclor 1260 exposure results in a decrease in virus early during infection and an increase during late infection. The consequences of this contaminant-induced infection pattern in a highly susceptible host could result in a greater potential for systemic infection with greater viral load, which could explain the correlative findings seen in wild populations exposed to a range of persistent contaminants that suffer from morbillivirus epizootics. PMID:26142119

  20. Disruption of the thyroid system by the thyroid-disrupting compound Aroclor 1254 in juvenile Japanese flounder (Paralichthys olivaceus.

    Directory of Open Access Journals (Sweden)

    Yifei Dong

    Full Text Available Polychlorinated biphenyls (PCBs are a group of persistent organochlorine compounds that have the potential to disrupt the homeostasis of thyroid hormones (THs in fish, particularly juveniles. In this study, thyroid histology, plasma TH levels, and iodothyronine deiodinase (IDs, including ID1, ID2, and ID3 gene expression patterns were examined in juvenile Japanese flounder (Paralichthys olivaceus following 25- and 50-day waterborne exposure to environmentally relevant concentrations of a commercial PCB mixture, Aroclor 1254 (10, 100, and 1000 ng/L with two-thirds of the test solutions renewed daily. The results showed that exposure to Aroclor 1254 for 50 d increased follicular cell height, colloid depletion, and hyperplasia. In particular, hypothyroidism, which was induced by the administration of 1000 ng/L Aroclor 1254, significantly decreased plasma TT4, TT3, and FT3 levels. Profiles of the changes in mRNA expression levels of IDs were observed in the liver and kidney after 25 and 50 d PCB exposure, which might be associated with a reduction in plasma THs levels. The expression level of ID2 mRNA in the liver exhibited a dose-dependent increase, indicating that this ID isotype might serve as sensitive and stable indicator for thyroid-disrupting chemical (TDC exposure. Overall, our study confirmed that environmentally relevant concentrations of Aroclor 1254 cause significant thyroid disruption, with juvenile Japanese flounder being suitable candidates for use in TDC studies.

  1. Evaluation of Aroclor 1260 exposure in a mouse model of diet-induced obesity and non-alcoholic fatty liver disease

    Energy Technology Data Exchange (ETDEWEB)

    Wahlang, Banrida [Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202 (United States); Song, Ming [Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY 40202 (United States); Beier, Juliane I. [Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202 (United States); Cameron Falkner, K. [Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY 40202 (United States); Al-Eryani, Laila [Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202 (United States); Clair, Heather B.; Prough, Russell A. [Department of Biochemistry and Molecular Biology, University of Louisville School of Medicine, Louisville, KY 40202 (United States); Osborne, Tanasa S.; Malarkey, David E. [Cellular and Molecular Pathology Branch, National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709 (United States); Christopher States, J. [Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202 (United States); Cave, Matthew C., E-mail: matt.cave@louisville.edu [Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40202 (United States); Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Louisville School of Medicine, Louisville, KY 40202 (United States); The Robley Rex Veterans Affairs Medical Center, Louisville, KY 40206 (United States)

    2014-09-15

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants associated with non-alcoholic fatty liver disease (NAFLD) in epidemiologic studies. The purpose of this study was to evaluate the hepatic effects of a PCB mixture, Aroclor 1260, whose composition mimics human bioaccumulation patterns, in a mouse model of diet-induced obesity (DIO). Male C57Bl/6J mice were fed control diet or 42% high fat diet (HFD) and exposed to Aroclor 1260 (20 mg/kg or 200 mg/kg in corn oil) for 12 weeks. A glucose tolerance test was performed; plasma/tissues were obtained at necropsy for measurements of adipocytokine levels, histology, and gene expression. Aroclor 1260 exposure was associated with decreased body fat in HFD-fed mice but had no effect on blood glucose/lipid levels. Paradoxically, Aroclor 1260 + HFD co-exposed mice demonstrated increased hepatic inflammatory foci at both doses while the degree of steatosis did not change. Serum cytokines, ALT levels and hepatic expression of IL-6 and TNFα were increased only at 20 mg/kg, suggesting an inhibition of pro-inflammatory cytokine production at the 200 mg/kg exposure. Aroclor 1260 induced hepatic expression of cytochrome P450s including Cyp3a11 (Pregnane-Xenobiotic Receptor target) and Cyp2b10 (constitutive androstane receptor target) but Cyp2b10 inducibility was diminished with HFD-feeding. Cyp1a2 (aryl hydrocarbon Receptor target) was induced only at 200 mg/kg. In summary, Aroclor 1260 worsened hepatic and systemic inflammation in DIO. The results indicated a bimodal response of PCB-diet interactions in the context of inflammation which could potentially be explained by xenobiotic receptor activation. Thus, PCB exposure may be a relevant “second hit” in the transformation of steatosis to steatohepatitis. - Highlights: • Aroclor 1260 exposure decreased adiposity in mice fed with high fat diet • Aroclor 1260 exposure induced steatohepatitis in diet-induced obese mice • Aroclor 1260 (20 and 200 mg/kg) induced

  2. Evaluation of Aroclor 1260 exposure in a mouse model of diet-induced obesity and non-alcoholic fatty liver disease

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants associated with non-alcoholic fatty liver disease (NAFLD) in epidemiologic studies. The purpose of this study was to evaluate the hepatic effects of a PCB mixture, Aroclor 1260, whose composition mimics human bioaccumulation patterns, in a mouse model of diet-induced obesity (DIO). Male C57Bl/6J mice were fed control diet or 42% high fat diet (HFD) and exposed to Aroclor 1260 (20 mg/kg or 200 mg/kg in corn oil) for 12 weeks. A glucose tolerance test was performed; plasma/tissues were obtained at necropsy for measurements of adipocytokine levels, histology, and gene expression. Aroclor 1260 exposure was associated with decreased body fat in HFD-fed mice but had no effect on blood glucose/lipid levels. Paradoxically, Aroclor 1260 + HFD co-exposed mice demonstrated increased hepatic inflammatory foci at both doses while the degree of steatosis did not change. Serum cytokines, ALT levels and hepatic expression of IL-6 and TNFα were increased only at 20 mg/kg, suggesting an inhibition of pro-inflammatory cytokine production at the 200 mg/kg exposure. Aroclor 1260 induced hepatic expression of cytochrome P450s including Cyp3a11 (Pregnane-Xenobiotic Receptor target) and Cyp2b10 (constitutive androstane receptor target) but Cyp2b10 inducibility was diminished with HFD-feeding. Cyp1a2 (aryl hydrocarbon Receptor target) was induced only at 200 mg/kg. In summary, Aroclor 1260 worsened hepatic and systemic inflammation in DIO. The results indicated a bimodal response of PCB-diet interactions in the context of inflammation which could potentially be explained by xenobiotic receptor activation. Thus, PCB exposure may be a relevant “second hit” in the transformation of steatosis to steatohepatitis. - Highlights: • Aroclor 1260 exposure decreased adiposity in mice fed with high fat diet • Aroclor 1260 exposure induced steatohepatitis in diet-induced obese mice • Aroclor 1260 (20 and 200 mg/kg) induced

  3. The three-species consortium of genetically improved strains Cupriavidus necator RW112, Burkholderia xenovorans RW118, and Pseudomonas pseudoalcaligenes RW120, grows with technical polychlorobiphenyl, Aroclor 1242

    Directory of Open Access Journals (Sweden)

    Regina-Michaela eWittich

    2013-04-01

    Full Text Available Burkholderia xenovorans LB400, Cupriavidus necator H850, and Pseudomonas pseudoalcaligenes KF707 are bacterial strains able to mineralize biphenyl and to co-oxidize many of its halogenated derivatives (PCBs. Only strain LB400 also mineralizes a few mono- and dichlorobiphenyls, due to the presence of a functioning chlorocatechol pathway. Here, we used a Tn5-based minitransposon shuttle system to chromosomically introduce genes tcbRCDEF, encoding the chlorocatechol pathway into KF707, and genes cbdABC encoding a 2-chlorobenzoate 1,2-dioxygenase into KF707 and LB400, as well as transposon Tn4653 from the TOL plasmid providing genes xylXYZL, encoding a broad-range toluate (methylbenzoate dioxygenase and its dihydrodiol dehydrogenase, to extend the range for the mineralization of halogenated benzoates in LB400 and in KF707. The engineered derivatives of LB400, and KF707 thus gained the ability for the mineralization of all isomeric monochloro- and bromobenzoates of the so-called lower pathway which, consequently, also allowed the mineralization of all monochlorobiphenyls and a number of di- and trichlorobiphenyls, thus preventing the accumulation of halobenzoates and of catabolites thereof. LB400 and KF707 also grow with the two commercial PCB formulations, Aroclor 1221 and Aroclor 1232, as the sole carbon and energy sources, but not with higher halogenated PCB mixtures, similar to the already published strain RW112. Repeated exposition of the modified LB400 to short pulses of UV light, over a prolonged period of time, allowed the isolation of a derivative of LB400, termed RW118, capable of growth with Aroclor 1016 still containing only traces of biphenyl, and in co-culture with modified KF707 termed RW120, and modified H850 (RW112 with Aroclor 1242, the commercial mixture already void of biphenyl and monochlorobiphenyls.

  4. Plant compounds that induce polychlorinated biphenyl biodegradation by Arthrobacter sp. strain B1B.

    OpenAIRE

    Gilbert, E S; Crowley, D. E.

    1997-01-01

    Plant compounds that induced Arthrobacter sp. strain B1B to cometabolize polychlorinated biphenyls (PCBs) were identified by a screening assay based on the formation of a 4,4'-dichlorobiphenyl ring fission product. A chemical component of spearmint (Mentha spicata), l-carvone, induced Arthrobacter sp. strain B1B to cometabolize Aroclor 1242, resulting in significant degradation of 26 peaks in the mixture, including selected tetra- and pentachlorobiphenyls. Evidence for PCB biodegradation incl...

  5. Thermophysical properties of (diphenyl ether + biphenyl) mixtures for their use as heat transfer fluids

    International Nuclear Information System (INIS)

    Highlights: ► Densities at high pressure of mixtures of diphenyl ether and biphenyl were reported. ► The composition dependence on thermal conductivity and viscosity is very smooth. ► Crossing point in αp isotherms were detected around 38 MPa. ► MYEGA reproduces our experimental η(T) curves with deviations lower than 0.24%. ► The experimental devices were checked obtaining good agreements with literature. - Abstract: Experimental measurements of density, viscosity and thermal conductivity are reported for pure diphenyl ether and three different binary mixtures of diphenyl ether and biphenyl including the eutectic point. Density has been measured for the liquid phase at temperatures ranging from (298.15 to 363.15) K and for pressures up to 45 MPa using a high-pressure vibrating tube densimeter. A Tammann–Tait correlation of the experimental densities has been proposed for each composition. From these correlations, isothermal compressibility, isobaric thermal expansivity and internal pressure have been determined. Moreover, viscosity and thermal conductivity were experimentally determined at atmospheric pressure for several temperatures by using a rolling ball viscometer and a device based in the hot-wire technique, respectively. All the experimental devices used to determine the thermophysical properties were checked finding good agreements with previous literature data. The experimental viscosity values were correlated using the Vogel–Fulcher–Tammann, Avramov–Milchev and MYEGA equation.

  6. Exposure to Chlorinated Biphenyls Causes Polymorphonucleocytes to Induce Progenitor Cell Toxicity in Culture

    Directory of Open Access Journals (Sweden)

    Tanika V. Martin

    2006-03-01

    Full Text Available Progenitor cells (PC are the precursors for many developmental structures and are sensitive to a variety of toxic agents including the environmental contaminants, polychlorinated biphenyls (PCBs. The mechanism(s that contributes to the development of PCB-induced progenitor cell-related fetotoxicities are not completely understood. However, several studies have demonstrated an important role for neutrophils (polymorphonucleocytes in the development of PCB induced toxicities. Our recent findings have indicated that conditioned medium collected from PC (CMPC exposed to a single dose of the PCB mixture, Aroclor 1248, can activate isolated neutrophil populations. Because of our recent findings, this study was conducted to determine if conditioned medium from PC treated with a PCB mixture causes neutrophils to injure PC in culture. Isolated PC were cultured and treated with different concentrations of Aroclor 1248 for 24 hours. The resulting PC-derived conditioned media was collected and its affect on neutrophil activity was analyzed. Conditioned medium from PC treated with Aroclor 1248 was chemotactic for neutrophils. The conditioned medium from Aroclor 1248 treated-PC also stimulated neutrophils to release super oxide anion, cathepsin G and elastase into culture medium. Furthermore, the conditioned medium from Aroclor 1248 treated- PC was able to stimulate neutrophils to cause progenitor cell toxicity in co-cultures. The conditioned medium from Aroclor 1248 treated-PC was not toxic to individual neutrophil cultures or PC cultures. Moreover, the addition of a protease inhibitor to the co-cultures containing neutrophils and PC, afforded protection against neutrophil-induced cytotoxicity of PC. These data suggest that a PCB mixture can cause progenitor cells to produce a factor(s that activates neutrophils and stimulates them to damage PC populations in culture.

  7. Analysis the mixtures of polyphenyls by gas chromatrogaphie. 1.- Area response for biphenyl and terphenyls relative to triphenylmethane

    International Nuclear Information System (INIS)

    The relative performances of the thermal conductivity and flame ionization detectors towards triphenylmethane were investigated for each one of the components of biphenyl of biphenyl and terphenyl mixtures. The influence of the concentration of the considered compound as well as the influence derived from the present of all other components on the above-mentioned relative performance were studied. A 2 m long column filled with 50-70 mesh stomacher containing 20% apiezon L was used to carry out the study with the thermal conductivity detector by keeping the column at 300 degree centigree using helium gas as carrier. (Author) 13 refs

  8. Developmental Exposure to Aroclor 1254 Alters Migratory Behavior in Juvenile European Starlings (Sturnus vulgaris).

    Science.gov (United States)

    Flahr, Leanne M; Michel, Nicole L; Zahara, Alexander R D; Jones, Paul D; Morrissey, Christy A

    2015-05-19

    Birds exposed to endocrine disrupting chemicals during development could be susceptible to neurological and other physiological changes affecting migratory behaviors. We investigated the effects of ecologically relevant levels of Aroclor 1254, a polychlorinated biphenyl (PCB) mixture, on moult, fattening, migratory activity, and orientation in juvenile European starlings (Sturnus vulgaris). Birds were orally administered 0 (control), 0.35 (low), 0.70 (intermediate), or 1.05 (high) μg Aroclor 1254/g-body weight by gavage from 1 through 18 days posthatch and later exposed in captivity to a photoperiod shift simulating an autumn migration. Migratory activity and orientation were examined using Emlen funnel trials. Across treatments, we found significant increases in mass, fat, and moulting and decreasing plasma thyroid hormones over time. We observed a significant increase in activity as photoperiod was shifted from 13L:11D (light:dark) to 12L:12D, demonstrating that migratory condition was induced in captivity. At 12L:12D, control birds oriented to 155.95° (South-Southeast), while high-dosed birds did not. High-dosed birds showed a delayed orientation to 197.48° (South-Southwest) under 10L:14D, concomitant with apparent delays in moult. These findings demonstrate how subtle contaminant-induced alterations during development could lead to longer-scale effects, including changes in migratory activity and orientation, which could potentially result in deleterious effects on fitness and survival.

  9. Construction of a bioluminescent reporter strain to detect polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Layton, A.C.; Muccini, M.; Ghosh, M.M.; Sayler, G.S. [Univ. of Tennessee, Knoxville, TN (United States)

    1998-12-01

    A bioluminescent reporter strain, Ralstonia eutropha ENV307 (pUTK60), was constructed for the detection of polychlorinated biphenyls by inserting the biphenyl promoter upstream of the bioluminescence genes. In the presence of a nonionic surfactant, which enhances the solubility of chlorinated biphenyls, bioluminescence was induced three- to fourfold over background by biphenyl, monochlorinated biphenyls, and Aroclor 1242. The minimum detection limits for these compounds ranged from 0.15 mg/liter for 4-chlorobiphenyl to 1.5 mg/liter for Aroclor 1242.

  10. Construction of a Bioluminescent Reporter Strain To Detect Polychlorinated Biphenyls

    OpenAIRE

    Layton, A C; Muccini, M.; Ghosh, M. M.; Sayler, G. S.

    1998-01-01

    A bioluminescent reporter strain, Ralstonia eutropha ENV307(pUTK60), was constructed for the detection of polychlorinated biphenyls by inserting the biphenyl promoter upstream of the bioluminescence genes. In the presence of a nonionic surfactant, which enhances the solubility of chlorinated biphenyls, bioluminescence was induced three- to fourfold over background by biphenyl, monochlorinated biphenyls, and Aroclor 1242. The minimum detection limits for these compounds ranged from 0.15 mg/lit...

  11. Production of metabolites from chloro biphenyls by resting cells of Pseudomonas strain LB400 after growth on different carbon sources

    International Nuclear Information System (INIS)

    The transformation of polychlorinated biphenyl (PCB), when exposed to microorganisms, into chlorobenzoic acid metabolites was studied. PCBs are widely used in electrical transformers and have become widely dispersed in the environment. A proposed system for clean up of PCBs involves the combined use of anaerobic reductive dehalogenation of highly chlorinated congeners followed by aerobic degradation of moderately chlorinated PCBs, mediated by oxidative ring attack. Much of this work focused on biphenyl-grown cells, in particular Pseudomonas strain LB400 grown on biphenyl, which contains a multicomponent enzyme system. It was shown that resting cells of Pseudomonas strain LB400, grown on glycerol or glucose, could also transform purified PCB congeners and mixtures of PCBs in Aroclors, however, transformation rates were less than those observed with biphenyl-grown cells. 29 refs., 2 tabs., 2 figs

  12. Alteration of rat fetal cerebral cortex development after prenatal exposure to polychlorinated biphenyls.

    Directory of Open Access Journals (Sweden)

    Elise Naveau

    Full Text Available Polychlorinated biphenyls (PCBs are environmental contaminants that persist in environment and human tissues. Perinatal exposure to these endocrine disruptors causes cognitive deficits and learning disabilities in children. These effects may involve their ability to interfere with thyroid hormone (TH action. We tested the hypothesis that developmental exposure to PCBs can concomitantly alter TH levels and TH-regulated events during cerebral cortex development: progenitor proliferation, cell cycle exit and neuron migration. Pregnant rats exposed to the commercial PCB mixture Aroclor 1254 ended gestation with reduced total and free serum thyroxine levels. Exposure to Aroclor 1254 increased cell cycle exit of the neuronal progenitors and delayed radial neuronal migration in the fetal cortex. Progenitor cell proliferation, cell death and differentiation rate were not altered by prenatal exposure to PCBs. Given that PCBs remain ubiquitous, though diminishing, contaminants in human systems, it is important that we further understand their deleterious effects in the brain.

  13. Effects of Quercetin on CYP450 and Cytokines in Aroclor 1254 Injured Endometrial Cells of the Pregnant Rats

    Directory of Open Access Journals (Sweden)

    Lina Xu

    2014-01-01

    Full Text Available Polychlorinated biphenyls (PCBs are widespread persistent residual environmental pollutants, which affect seriously the growth and reproductive alterations in humans and animals. Aroclor 1254 is a commercial mixture of PCBs. Quercetin is a flavonoid, which acts on estrogen receptors and causes the development of estrogen-related diseases. In this paper, the primary cultured endometrial cells in the pregnant rats were isolated and Aroclor 1254 was used to induce the injured endometrial cells model. The cells were treated with gradient quercetin, the viability of the endometrial cells, the expressions of CYP450, the contents of TNF-α, IL-6, estradiol (E2, and progesterone (P4 were measured. It showed that the viability of the cultured endometrial cells, the expression of CYP1A1 and CYP2B1, and the contents of TNF-α, E2, and IL-6 in the injured endometrial cells increased with the treatment of quercetin. It shows that quercetin has protective effect on the injured endometrial cells in the pregnant rats, this provide a basis on herbal medicine protection for animal reproductive diseases caused by environmental endocrine disruptors.

  14. Polychlorinated Biphenyl-Xenobiotic Nuclear Receptor Interactions Regulate Energy Metabolism, Behavior, and Inflammation in Non-alcoholic-Steatohepatitis.

    Science.gov (United States)

    Wahlang, Banrida; Prough, Russell A; Falkner, K Cameron; Hardesty, Josiah E; Song, Ming; Clair, Heather B; Clark, Barbara J; States, J Christopher; Arteel, Gavin E; Cave, Matthew C

    2016-02-01

    Polychlorinated biphenyls (PCBs) are environmental pollutants associated with non-alcoholic-steatohepatitis (NASH), diabetes, and obesity. We previously demonstrated that the PCB mixture, Aroclor 1260, induced steatohepatitis and activated nuclear receptors in a diet-induced obesity mouse model. This study aims to evaluate PCB interactions with the pregnane-xenobiotic receptor (Pxr: Nr1i2) and constitutive androstane receptor (Car: Nr1i3) in NASH. Wild type C57Bl/6 (WT), Pxr(-/-) and Car(-/-) mice were fed the high fat diet (42% milk fat) and exposed to a single dose of Aroclor 1260 (20 mg/kg) in this 12-week study. Metabolic phenotyping and analysis of serum, liver, and adipose was performed. Steatohepatitis was pathologically similar in all Aroclor-exposed groups, while Pxr(-/-) mice displayed higher basal pro-inflammatory cytokine levels. Pxr repressed Car expression as evident by increased basal Car/Cyp2b10 expression in Pxr(-/-) mice. Both Pxr(-/-) and Car(-/-) mice showed decreased basal respiratory exchange rate (RER) consistent with preferential lipid metabolism. Aroclor increased RER and carbohydrate metabolism, associated with increased light cycle activity in both knockouts, and decreased food consumption in the Car(-/-) mice. Aroclor exposure improved insulin sensitivity in WT mice but not glucose tolerance. The Aroclor-exposed, Pxr(-/-) mice displayed increased gluconeogenic gene expression. Lipid-oxidative gene expression was higher in WT and Pxr(-/-) mice although RER was not changed, suggesting PCB-mediated mitochondrial dysfunction. Therefore, Pxr and Car regulated inflammation, behavior, and energy metabolism in PCB-mediated NASH. Future studies should address the 'off-target' effects of PCBs in steatohepatitis.

  15. A disposable immunomagnetic electrochemical sensor based on functionalised magnetic beads and carbon-based screen-printed electrodes (SPCEs) for the detection of polychlorinated biphenyls (PCBs)

    International Nuclear Information System (INIS)

    A disposable immunomagnetic electrochemical sensor involving magnetic particles and carbon-based screen-printed electrodes (SPCEs) was developed and applied for the detection of polychlorinated biphenyls (PCBs). The sensor was based on a direct competitive immunoassay scheme in which antibody-coated magnetic beads were used as solid phase; then SPCEs were employed as transducers for the evaluation of the extent of the immunochemical reaction using an alkaline phosphatase (AP) labelled tracer. The α-naphthyl phosphate was used as enzymatic substrate and the α-naphthol produced during the enzymatic reaction was detected using differential pulse voltammetry (DPV). A detection limit of 0.4 ng/mL for Aroclor 1248 PCB mixture was obtained. The performance of the sensor was successfully evaluated on marine sediment extracts and soil samples spiked with different Aroclor mixtures indicating that this new and sensitive technique offers great promise for decentralized environmental applications

  16. A disposable immunomagnetic electrochemical sensor based on functionalised magnetic beads and carbon-based screen-printed electrodes (SPCEs) for the detection of polychlorinated biphenyls (PCBs)

    Energy Technology Data Exchange (ETDEWEB)

    Centi, S. [Universita degli Studi di Firenze, Dipartimento di Chimica, Polo Scientifico, via della Lastruccia 3, 50019 Sesto Fiorentino, Florence (Italy)]. E-mail: marco.mascini@unifi.it; Laschi, S. [Universita degli Studi di Firenze, Dipartimento di Chimica, Polo Scientifico, via della Lastruccia 3, 50019 Sesto Fiorentino, Florence (Italy); Franek, M. [Veterinary Research Institute, Hudcova 70, 62132 Brno (Czech Republic); Mascini, M. [Universita degli Studi di Firenze, Dipartimento di Chimica, Polo Scientifico, via della Lastruccia 3, 50019 Sesto Fiorentino, Florence (Italy)

    2005-05-04

    A disposable immunomagnetic electrochemical sensor involving magnetic particles and carbon-based screen-printed electrodes (SPCEs) was developed and applied for the detection of polychlorinated biphenyls (PCBs). The sensor was based on a direct competitive immunoassay scheme in which antibody-coated magnetic beads were used as solid phase; then SPCEs were employed as transducers for the evaluation of the extent of the immunochemical reaction using an alkaline phosphatase (AP) labelled tracer. The {alpha}-naphthyl phosphate was used as enzymatic substrate and the {alpha}-naphthol produced during the enzymatic reaction was detected using differential pulse voltammetry (DPV). A detection limit of 0.4 ng/mL for Aroclor 1248 PCB mixture was obtained. The performance of the sensor was successfully evaluated on marine sediment extracts and soil samples spiked with different Aroclor mixtures indicating that this new and sensitive technique offers great promise for decentralized environmental applications.

  17. Aroclor 1254, a developmental neurotoxicant, alters energy metabolism- and intracellular signaling-associated protein networks in rat cerebellum and hippocampus

    Energy Technology Data Exchange (ETDEWEB)

    Kodavanti, Prasada Rao S., E-mail: kodavanti.prasada@epa.gov [Neurotoxicology Branch, NHEERL, ORD, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina (United States); Osorio, Cristina [Systems Proteomics Center, University of North Carolina at Chapel Hill, North Carolina (United States); Program on Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, North Carolina (United States); Royland, Joyce E.; Ramabhadran, Ram [Genetic and Cellular Toxicology Branch, NHEERL, ORD, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina (United States); Alzate, Oscar [Department of Cellular and Developmental Biology, University of North Carolina at Chapel Hill, North Carolina (United States); Systems Proteomics Center, University of North Carolina at Chapel Hill, North Carolina (United States); Program on Molecular Biology and Biotechnology, University of North Carolina at Chapel Hill, North Carolina (United States)

    2011-11-15

    The vast literature on the mode of action of polychlorinated biphenyls (PCBs) indicates that PCBs are a unique model for understanding the mechanisms of toxicity of environmental mixtures of persistent chemicals. PCBs have been shown to adversely affect psychomotor function and learning and memory in humans. Although the molecular mechanisms for PCB effects are unclear, several studies indicate that the disruption of Ca{sup 2+}-mediated signal transduction plays significant roles in PCB-induced developmental neurotoxicity. Culminating events in signal transduction pathways include the regulation of gene and protein expression, which affects the growth and function of the nervous system. Our previous studies showed changes in gene expression related to signal transduction and neuronal growth. In this study, protein expression following developmental exposure to PCB is examined. Pregnant rats (Long Evans) were dosed with 0.0 or 6.0 mg/kg/day of Aroclor-1254 from gestation day 6 through postnatal day (PND) 21, and the cerebellum and hippocampus from PND14 animals were analyzed to determine Aroclor 1254-induced differential protein expression. Two proteins were found to be differentially expressed in the cerebellum following PCB exposure while 18 proteins were differentially expressed in the hippocampus. These proteins are related to energy metabolism in mitochondria (ATP synthase, sub unit {beta} (ATP5B), creatine kinase, and malate dehydrogenase), calcium signaling (voltage-dependent anion-selective channel protein 1 (VDAC1) and ryanodine receptor type II (RyR2)), and growth of the nervous system (dihydropyrimidinase-related protein 4 (DPYSL4), valosin-containing protein (VCP)). Results suggest that Aroclor 1254-like persistent chemicals may alter energy metabolism and intracellular signaling, which might result in developmental neurotoxicity. -- Highlights: Black-Right-Pointing-Pointer We performed brain proteomic analysis of rats exposed to the neurotoxicant

  18. Aroclor 1248 exposure leads to immunomodulation, decreased disease resistance and endocrine disruption in the brown bullhead, Ameiurus nebulosus

    Science.gov (United States)

    Iwanowicz, L.R.; Blazer, V.S.; McCormick, S.D.; Van Veld, P.A.; Ottinger, C.A.

    2009-01-01

    The brown bullhead Ameiurus nebulosus is a species of the family Ictaluridae commonly used as a sentinel of environmental contamination. While these fish have been utilized for this purpose in areas contaminated with polychlorinated biphenyls (PCBs), few controlled, laboratory-based studies have been designed to document the effects of PCB mixtures in this species. Here, brown bullhead were exposed to the PCB mixture, Aroclor 1248, via intraperitoneal injection and the effects on immune function, plasma hormones and disease resistance were evaluated. Exposure to this mixture led to a decrease in bactericidal activity and circulating antibodies to Edwardsiella ictaluri present from a previous exposure to this pathogen. A subsequent E. ictaluri disease challenge led to significantly higher mortality in A1248 treated fish compared to vehicle-control fish. The mitogenic response to the T-cell mitogen, phytohemaglutinin-P, was increased compared to vehicle-control fish. The steroid hormone, cortisol, and the thyroid hormone, T3, were also significantly lower in A1248 exposed fish. In summary, we have validated a number of functional immune assays for application in brown bullhead immunotoxicity studies. Additionally, we have demonstrated that the PCB mixture (A1248) modulates both immune function and endocrine physiology in brown bullhead. Such data may compliment the interpretation of data yielded from applied field studies conducted in PCB contaminated aquatic ecosystems.

  19. Preliminary survey of polychlorinated biphenyls (PCBs) in aquatic habitats and Great Blue Herons on the Hanford Site. [Ardea herodias

    Energy Technology Data Exchange (ETDEWEB)

    Riley, R.G.; Bean, R.M.; Fitzner, R.E.; Neitzel, D.A.; Rickard, W.H.

    1986-01-01

    Polychlorinated biphenyls (PCBs), constituents of insulating fluids used in electrical transformers and capacitors, were identified during a preliminary survey of waters, sediments, and fish from five locations on the Hanford Site in southeastern Washington State: Gable Mountain Pond, B Pond, West Pond, White Bluffs Slough on the Columbia River, and a pond on the Wahluke Slope. These aquatic areas are all within the foraging range of great blue herons (Ardea herodias) that nest on the Hanford Site. Of those waters that contained PCBs, concentrations were found to be somewhat over 1 ng/L, but less than 20 ng/L, and equal to or less than concentrations reported for other freshwater regions of the United States. The PCBs in sediments and fish closely resembled the chromatographic profile of Aroclor 1260, a commercial PCB mixture produced in the United States by the Monsanto Company. Concentrations of PCBs detected in the sediments were 10 to 100 times lower than those found in soils and sediments from other areas of the nation. Concentrations of PCBs in fat from Hanford great blue herons ranged from 3.6 to 10.6 ppM, while PCB concentrations in herons from other areas of the Pacific Northwest ranged from 0.6 to 15.6 ppM. Great blue herons at Hanford contained PCB isomer distributions closely matching that of Aroclor 1260; great blue herons from other locations contained isomer distributions indicating the presence of a mixture of aroclors. 21 refs., 13 figs., 8 tabs.

  20. Augmented atherogenesis in ApoE-null mice co-exposed to polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin

    International Nuclear Information System (INIS)

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) are persistent organic pollutants found as complex mixtures in the environment throughout the world. Therefore, humans are ubiquitously and simultaneously exposed to TCDD and PCBs. TCDD and PCBs alone have been linked to atherosclerosis. However, the effects of interactions or synergism between TCDD and PCBs on atherogenesis are unknown. We investigated the possible enhanced atherogenesis by co-exposure to TCDD and PCBs and the potential mechanism(s) involved in this enhancement. Male ApoE−/− mice were exposed to TCDD (15 μg/kg) and Aroclor1254 (55 mg/kg, a representative mixture of PCBs) alone or in combination by intraperitoneal injection four times over six weeks of duration. Our results showed that mice exposed to TCDD alone, but not Aroclor1254 alone, developed atherosclerotic lesions. Moreover, we found that atherosclerotic disease was exacerbated to the greatest extent in mice co-exposed to TCDD and Aroclor1254. The enhanced lesions correlated with several pro-atherogenic changes, including a marked increase in the accumulation of the platelet-derived chemokine PF4, and the expression of the proinflammatory cytokine MCP-1 and the critical immunity gene-RIG-I. Our data demonstrated that co-exposure to TCDD and Aroclor1254 markedly enhanced atherogenesis in ApoE−/− mice. Significantly, our observations suggest that combined exposure to TCDD and PCBs may be a greater cardiovascular health risk than previously anticipated from individual studies. - Highlights: • Augmented atherogenesis was found in ApoE−/− mice co-exposed to Aroclor1254 and TCDD. • Enhanced expression of PF4, MCP-1 and RIG-I correlated with augmented lesions. • POPs combination may be a greater cardiovascular health risk than individual POPs

  1. Augmented atherogenesis in ApoE-null mice co-exposed to polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin

    Energy Technology Data Exchange (ETDEWEB)

    Shan, Qiuli [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Wang, Jing, E-mail: avaecn@gmail.com [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Huang, Fengchen [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Lv, Xiaowen [Feed Safety Reference Laboratory of Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Zhongguancun South Street 12, Beijing 100081 (China); Ma, Min [Laboratory of Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Du, Yuguo [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)

    2014-04-15

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) are persistent organic pollutants found as complex mixtures in the environment throughout the world. Therefore, humans are ubiquitously and simultaneously exposed to TCDD and PCBs. TCDD and PCBs alone have been linked to atherosclerosis. However, the effects of interactions or synergism between TCDD and PCBs on atherogenesis are unknown. We investigated the possible enhanced atherogenesis by co-exposure to TCDD and PCBs and the potential mechanism(s) involved in this enhancement. Male ApoE{sup −/−} mice were exposed to TCDD (15 μg/kg) and Aroclor1254 (55 mg/kg, a representative mixture of PCBs) alone or in combination by intraperitoneal injection four times over six weeks of duration. Our results showed that mice exposed to TCDD alone, but not Aroclor1254 alone, developed atherosclerotic lesions. Moreover, we found that atherosclerotic disease was exacerbated to the greatest extent in mice co-exposed to TCDD and Aroclor1254. The enhanced lesions correlated with several pro-atherogenic changes, including a marked increase in the accumulation of the platelet-derived chemokine PF4, and the expression of the proinflammatory cytokine MCP-1 and the critical immunity gene-RIG-I. Our data demonstrated that co-exposure to TCDD and Aroclor1254 markedly enhanced atherogenesis in ApoE{sup −/−} mice. Significantly, our observations suggest that combined exposure to TCDD and PCBs may be a greater cardiovascular health risk than previously anticipated from individual studies. - Highlights: • Augmented atherogenesis was found in ApoE{sup −/−} mice co-exposed to Aroclor1254 and TCDD. • Enhanced expression of PF4, MCP-1 and RIG-I correlated with augmented lesions. • POPs combination may be a greater cardiovascular health risk than individual POPs.

  2. Bioaugmentation of a historically contaminated soil by polychlorinated biphenyls with Lentinus tigrinus

    Directory of Open Access Journals (Sweden)

    Federici Ermanno

    2012-03-01

    Full Text Available Abstract Background Several species belonging to the ecological group of white-rot basidiomycetes are able to bring about the remediation of matrices contaminated by a large variety of anthropic organic pollutants. Among them, polychlorobiphenyls (PCBs are characterized by a high recalcitrance due to both their low bioavailability and the inability of natural microbial communities to degrade them at significant rates and extents. Objective of this study was to assess the impact of a maize stalk-immobilized Lentinus tigrinus CBS 577.79 inoculant combined with soybean oil (SO, as a possible PCB-mobilizing agent, on the bioremediation and resident microbiota of an actual Aroclor 1260 historically contaminated soil under unsaturated solid-phase conditions. Results Best overall PCB depletions (33.6 ± 0.3% and dechlorination (23.2 ± 1.3% were found after 60 d incubation in the absence of SO where, however, the fungus appeared to exert adverse effects on both the growth of biphenyl- and chlorobenzoate-degrading bacteria and the abundance of genes coding for both biphenyl dioxygenase (bph and catechol-2,3-dioxygenase. A significant (P bph. Conclusions The PCB depletion extents obtained in the presence of L. tigrinus are by far higher than those reported in other remediation studies conducted under unsaturated solid phase conditions on actual site soils historically contaminated by Aroclor 1260. These results suggest that the bioaugmentation strategy with the maize stalk-immobilized mycelium of this species might be promising in the reclamation of PCB-contaminated soils. The addition of SO to matrices contaminated by technical PCB mixtures, such as Aroclor 1242 and Delor 103 and characterized by a large preponderance of low chlorinated congeners, might not be advisable.

  3. Anaemia, hypothyroidism and immune suppression associated with polychlorinated biphenyl exposure in bottlenose dolphins (Tursiops truncatus).

    Science.gov (United States)

    Schwacke, Lori H; Zolman, Eric S; Balmer, Brian C; De Guise, Sylvain; George, R Clay; Hoguet, Jennifer; Hohn, Aleta A; Kucklick, John R; Lamb, Steve; Levin, Milton; Litz, Jenny A; McFee, Wayne E; Place, Ned J; Townsend, Forrest I; Wells, Randall S; Rowles, Teresa K

    2012-01-01

    Polychlorinated biphenyls (PCBs), persistent chemicals widely used for industrial purposes, have been banned in most parts of the world for decades. Owing to their bioaccumulative nature, PCBs are still found in high concentrations in marine mammals, particularly those that occupy upper trophic positions. While PCB-related health effects have been well-documented in some mammals, studies among dolphins and whales are limited. We conducted health evaluations of bottlenose dolphins (Tursiops truncatus) near a site on the Georgia, United States coast heavily contaminated by Aroclor 1268, an uncommon PCB mixture primarily comprised of octa- through deca-chlorobiphenyl congeners. A high proportion (26%) of sampled dolphins suffered anaemia, a finding previously reported from primate laboratory studies using high doses of a more common PCB mixture, Aroclor 1254. In addition, the dolphins showed reduced thyroid hormone levels and total thyroxine, free thyroxine and triiodothyronine negatively correlated with PCB concentration measured in blubber (p = 0.039, dolphins when compared with previously sampled reference sites, and therefore probably did not contribute to the observed correlations. Our results clearly demonstrate that dolphins are vulnerable to PCB-related toxic effects, at least partially mediated through the endocrine system. The severity of the effects suggests that the PCB mixture to which the Georgia dolphins were exposed has substantial toxic potential and further studies are warranted to elucidate mechanisms and potential impacts on other top-level predators, including humans, who regularly consume fish from the same marine waters.

  4. Toxic effects of benzo[a]pyrene (Bap) and Aroclor1254 on embryogenesis, larval growth, survival and metamorphosis of the bivalve Meretrix meretrix.

    Science.gov (United States)

    Wang, Qing; Yang, Hongsheng; Liu, Baozhong; Wang, Xiaoyu

    2012-08-01

    To assess the potential toxicity of polycyclic aromatic hydrocarbons and polychlorinated biphenyls on the early development of Meretrix meretrix, the effects of benzo[a]pyrene (Bap) and Aroclor1254 on embryogenesis and larval development were investigated using static laboratory toxicity tests at nominal concentrations of 6.25-1,600 μg/L. Even at 1,600 μg/L, Bap and Aroclor1254 only caused minor reductions in embryo development rates. The 96 h LC(50) values for D-shaped larvae were 156 μg/L for Bap and 132 μg/L for Aroclor1254, respectively. The most sensitive toxicity endpoint in this study was metamorphosis, with an EC(50) value of 20 μg/L for Bap and 35 μg/L for Aroclor1254. Aroclor1254 was more toxic than Bap to embryos and larvae. Our results indicate that Bap and Aroclor1254 do not show extreme toxicity to M. meretrix embryos and larvae. These data provide information for evaluating the toxicity of Bap and Aroclor1254 on bivalve embryos, especially over the entire larval stages.

  5. The occurrence and significance of polychlorinated biphenyls in the environment

    Science.gov (United States)

    Dustman, E.H.; Stickel, L.F.; Blus, L.J.; Reichel, W.L.; Wiemeyer, Stanley N.

    1971-01-01

    SUMMARY: Polychlorinated biphenyls constitute a group of chlorine-bearing compounds of industrial origin that have permeated the natural environment throughout the world. Their chemical structure resembles that of some of the organochlorine pesticides. They are troublesome interferences in gas chromatographic analysis of these pesticides. Although methods have been developed to overcome analytical problems, measurements of quantity still are only approximate. Special studies in the United States, Netherlands, and Great Britain have traced PCB's to industrial effluent, but other possible sources have not been followed. Their use in paints, cartons, and insulating fluids suggests that environmental pollution may be from many different sources. PCB's are present in fish and wildlife in many countries of the world. Quantities are higher in animals living near industrial areas. PCB's build up in biological food chains with increases of tens to thousands of times from lower to higher organisms. Experimental studies have shown that PCB's have a toxicity to mallards, pheasants, bobwhite quail, coturnix quail, red-winged blackbirds, starlings, cowbirds, and grackles that is of the same order as the toxicity of DDE to these species. Overt signs of poisoning also are similar to those caused by compounds of the DDT group. Toxic effects of DDE and Aroclor 1254 to coturnix chicks were additive, but not synergistic. PCB's containing higher percentages of chlorine are more toxic to birds than those containing lower percentages. PCB's of foreign manufacture contained contaminants to an extent that greatly increased their toxicity Aroclor 1242. Statistical evaluations of the role that different chemicals may play in thinning of eggshells of brown pelicans show that DDE residues correlate better with shell thinning than do residues of dieldrin or PCB's. Studies of the effects of PCB's in the environment are as yet insufficient for well-rounded conclusions. The evidence available

  6. Polychlorinated biphenyl toxicity to Japanese quail as related to degree of chlorination

    Science.gov (United States)

    Hill, E.F.; Heath, R.G.; Spann, J.W.; Williams, J.D.

    1974-01-01

    To learn if the percentage of chlorine in a mixture of polychlorinated biphenyls (PCB's) alone determines toxicity, Japanese quail were fed diets containing Aroelor 1248, 1254, or 1260 at levels that added equal amounts of chlorine to the feed. The experiment comprised two consecutive 5-day periods; three sublethal concentrations of chlorine were evaluated during the first period and three lethal concentrations during the second period. Evaluations utilized comparisons of mortality, time to death, weight change, and food consumption. Sublethal concentrations produced no detectable effects. Lethal concentrations with equal Chlorine showed Aroelor 1248 to be less toxic at the highest chlorine concentrations, but at lower concentrations Aroelor 1254 was more toxic than Aroclor 1260. Although chlorine percentage of a PCB is positively correlated with its avian toxicity, PCB toxicity is apparently not simply a function of chlorination.

  7. DETERMINATION OF POLYCHLORINATED BIPHENYL LEVELS IN THE SERUM OF RESIDENTS AND IN THE HOMOGENATES OF SEAFOOD FROM THE NEW BEDFORD, MA AREA: A COMPARISON OF EXPOSURE SOURCES THROUGH PATTERN RECOGNITION TECHNIQUES

    Science.gov (United States)

    Gas chromatographic patterns of polychlorinated biphenyls (PCBS) found in the serum of New Bedford, MA residents with high serum PCBs were compared to patterns found in lobsters and bluefish taken from local waters, and goats fed selected technical Aroclors (e.g., Aroclors 1016, ...

  8. Courtship behavior of captive American kestrels (Falco sparverius) exposed to polychlorinated biphenyls.

    Science.gov (United States)

    Fisher, S A; Bortolotti, G R; Fernie, K J; Smits, J E; Marchant, T A; Drouillard, K G; Bird, D M

    2001-08-01

    Polychlorinated biphenyls (PCBs) adversely affect reproduction in birds. Captive adult male and female American kestrels (Falco sparverius) were studied to investigate the potential behavioral and hormonal alterations during the courtship period resulting from clinical exposure to PCBs. American kestrels ingested 7 mg/kg/body weight/bird/day of a 1:1:1 mixture of Aroclors 1248, 1254, and 1260 through their diet of day-old cockerels. The dietary dosage of Aroclors resulted in environmentally relevant total PCB residues in the eggs, averaging 34.1 microg/g wet weight (geometric mean). There was no difference between treatment and control birds in the circulating levels of total androgens (p = 0.44) or in 17 beta-estradiol (p = 0.29), one week following pairing. Male kestrels exposed to dietary PCBs exhibited significantly more sexual behaviors (p = 0.034) and flight behaviors (p = 0.026) than the control males. Sexual behaviors of male kestrels included; nest-box inspections, solicitation of copulation, the offer of food to the female, and giving the female food. The flight behaviors of the male included; flying from one perch to another and aerial display. In addition, the frequency of male sexual behaviors were correlated (r = 0.605, p = 0.001) with total PCB residues in the eggs of their mates. A concurrent study found that these same PCB-exposed kestrels experienced a delay in clutch initiation as well as a greater number of completely infertile clutches. PMID:11462146

  9. Health and productivity of dairy cows fed polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Willett, L.B.; Liu, T.T.; Durst, H.I.; Smith, K.L.; Redman, D.R.

    1987-07-01

    Holstein cows were studied through a complete lactation, a nonlactating period, and 42 days of a subsequent lactation for overt and subtle responses to a commercial mixture of polychlorinated biphenyls. Dosed cows (n = 4) received consecutive 60-day periods of daily dosing with 10, 100, and 1000 mg of Aroclor 1254. Control cows (n = 6) received daily sham doses. The following were recorded: daily milk production, feed intake, and health observations; weekly body weight, temperature, heart and respiratory rates and rectal palpation; semi-monthly clinical chemistry determinations; and monthly milk fat, microbiological culture of quarter foremilk samples, and composite milk somatic cell counts. Mean daily milk production (22.4 +/- 1.1 vs 24.8 +/- 1.0 kg) and net energy of a complete lactation (1.46 +/- 0.05 vs 1.45 +/- 0.03 Mcal/kg dry matter intake) were not different (p = 0.85) for control and PCB-dosed cows. Milk production during the first 42 days of the subsequent lactation was also similar for control and dosed cows. Occurrences of injuries, dysfunctions, and general infections were not related to polychlorinated biphenyl exposure. Intramammary infections were detected for both lactations with 51 and 32 infections detected in microbiological cultures, respectively, for the control and dosed groups. Environmental pathogens were most frequently isolated from cases of clinically apparent mastitis. The majority of quarter infections detected were due to Corynebacterium bovis. Only one animal (dosed, necropsy revealed left oviduct obstructed) failed to conceive with three to six services required before conception for the other control and dosed cows. Exposure to polychlorinated biphenyls resulting in maximal residues in milk fat, near 100 micrograms/g, had no apparent effect on health and productivity.

  10. Degradation of Aroclor 1242 Dechlorination Products in Sediments by Burkholderia xenovorans LB400(ohb) and Rhodococcus sp. Strain RHA1(fcb)

    OpenAIRE

    Rodrigues, Jorge L. M.; Kachel, C. Alan; Aiello, Michael R.; Quensen, John F.; Maltseva, Olga V.; Tsoi, Tamara V.; Tiedje, James M.

    2006-01-01

    Burkholderia xenovorans strain LB400, which possesses the biphenyl pathway, was engineered to contain the oxygenolytic ortho dehalogenation (ohb) operon, allowing it to grow on 2-chlorobenzoate and to completely mineralize 2-chlorobiphenyl. A two-stage anaerobic/aerobic biotreatment process for Aroclor 1242-contaminated sediment was simulated, and the degradation activities and genetic stabilities of LB400(ohb) and the previously constructed strain RHA1(fcb), capable of growth on 4-chlorobenz...

  11. Enhanced hepatotoxicity induced by repeated exposure to polychlorinated biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin in combination in male rats

    Institute of Scientific and Technical Information of China (English)

    Yimei Wang; Chunfeng Lu; Zhiguo Sheng; Gang Liu; Ze Fu; Benzhan Zhu; Shuangqing Peng

    2011-01-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) are among persistent polyhalogenated aromatic hydrocarbons that exist as complex mixtures in the environment worldwide. The present study was attempted to investigate the hepatotoxicity following repeated exposure to TCDD and PCBs in combination in male rats, and to reveal the involvement of potential mechanisms. Male Sprague-Dawley rats were exposed to TCDD (10 μg/kg) and Aroclor 1254 (10 mg/kg, a representative mixture of PCBs) alone or in combination by intragastric administration. After 12-day exposure, all treatments produced significant hepatotoxicity as characterized by changes of plasma biochemistry and histopathological changes. These effects were more prominent in the combined group. Furthermore, all treatments induced hepatic cytochrome P450 1A1 (CYP1A1) expression, and the maximal level of CYP1A1 expression was observed in the combined group, as in the case of the most severe hepatotoxicity evoked by the combined exposure.These findings indicated that the hepatotoxicity induced by TCDD and Aroclor 1254 might be ascribed to the high expression of hepatic CYP1A1. The present study demonstrates the enhanced hepatotoxicity after exposure to TCDD and PCBs in combination in rats.

  12. Phylogenetically distinct bacteria involve extensive dechlorination of aroclor 1260 in sediment-free cultures.

    Directory of Open Access Journals (Sweden)

    Shanquan Wang

    Full Text Available Microbial reductive dechlorination of the persistent polychlorinated biphenyls (PCBs is attracting much attention in cleanup of the contaminated environment. Nevertheless, most PCB dechlorinating cultures require presence of sediment or sediment substitutes to maintain their dechlorination activities which hinders subsequent bacterial enrichment and isolation processes. The information on enriching sediment-free PCB dechlorinating cultures is still limited. In this study, 18 microcosms established with soils and sediments were screened for their dechlorination activities on a PCB mixture - Aroclor 1260. After one year of incubation, 10 out of 18 microcosms showed significant PCB dechlorination with distinct dechlorination patterns (e.g., Process H, N and T classified based on profiles of PCB congeners loss and new congeners formation. Through serial transfers in defined medium, six sediment-free PCB dechlorinating cultures (i.e., CW-4, CG-1, CG-3, CG-4, CG-5 and SG-1 were obtained without amending any sediment or sediment-substitutes. PCB dechlorination Process H was the most frequently observed dechlorination pattern, which was found in four sediment-free cultures (CW-4, CG-3, CG-4 and SG-1. Sediment-free culture CG-5 showed the most extensive PCB dechlorination among the six cultures, which was mediated by Process N, resulting in the accumulation of penta- (e.g., 236-24-CB and tetra-chlorobiphenyls (tetra-CBs (e.g., 24-24-CB, 24-25-CB, 24-26-CB and 25-26-CB via dechlorinating 30.44% hepta-CBs and 59.12% hexa-CBs after three months of incubation. For culture CG-1, dechlorinators mainly attacked double flanked meta-chlorines and partially ortho-chlorines, which might represent a novel dechlorination pattern. Phylogenetic analysis showed distinct affiliation of PCB dechlorinators in the microcosms, including Dehalogenimonas and Dehalococcoides species. This study broadens our knowledge in microbial reductive dechlorination of PCBs, and provides

  13. Determination of Polychlorinated Biphenyls in Soil and Sediment by Selective Pressurized Liquid Extraction with Immunochemical Detection

    Science.gov (United States)

    A selective liquid pressurized extraction (SPLE) method was developed as a streamlined sample preparation/cleanup procedure for determining Aroclors and coplanar polychlorinated biphenyls (PCBs) in soil and sediment matrices. The SPLE method was coupled with an enzyme-linked imm...

  14. Dermal toxicity studies of technical polychlorinated biphenyls and fractions thereof in rabbits

    NARCIS (Netherlands)

    Vos, J.G.; Beems, R.B.

    1971-01-01

    A significant difference in toxicity between 3 polychlorinated biphenyl (PCB) preparations was found in a prior study: Clophen A 60 and Phenoclor DP6 showing the highest, Aroclor 1260 the lowest, toxicity (Vos and Koeman, 1970). A subsequent study revealed the presence of tetra- and pentachlorodiben

  15. Inhibition of LPS-induced splenocyte proliferation by ortho-substituted polychlorinated biphenyl congeners

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) are persistent environmental contaminants, and their ubiquitous nature has prompted studies of their potential health hazards. As a result of their lipophilic nature, PCBs accumulate in breast milk and subsequently affect the health of offspring of exposed individuals. Biological effects of PCBs in animals have mostly been attributed to coplanar congeners, although effects of ortho congeners also have been demonstrated. To investigate the relationship of immunotoxicity and chlorine substitution pattern, the effects of PCB congeners and mixtures of ortho and non-ortho-substituted constituents of Aroclor 1242 on splenocytes from C57B1/6 mice were examined. The immunotoxic endpoints investigated included splenocyte viability, lipopolysaccharide (LPS)-induced splenocyte proliferation, and LPS-induced antibody secretion. Congeners with multiple ortho chlorines preferentially inhibited splenocyte proliferation as compared with non- or mono-ortho-substituted congeners. However, mixtures of non- and mono-ortho-substituted congeners and multi-ortho-substituted congeners inhibited LPS-induced splenocyte proliferation and antibody secretion at similar concentrations. Exposure of splenocytes to these mixtures did not activate the aryl hydrocarbon receptor (AhR) signal transduction pathway. These results suggest individual multi-ortho-substituted congeners preferentially inhibit LPS-induced splenocyte proliferation, while congeners not exhibiting an effect individually may have additive effects in a mixture to produce an immunotoxic response through an AhR-independent pathway

  16. Dehalorespiration with Polychlorinated Biphenyls by an Anaerobic Ultramicrobacterium▿

    OpenAIRE

    May, Harold D.; Miller, Greg S.; Birthe V. Kjellerup; Sowers, Kevin R.

    2008-01-01

    Anaerobic microbial dechlorination is an important step in the detoxification and elimination of polychlorinated biphenyls (PCBs), but a microorganism capable of coupling its growth to PCB dechlorination has not been isolated. Here we describe the isolation from sediment of an ultramicrobacterium, strain DF-1, which is capable of dechlorinating PCBs containing double-flanked chlorines added as single congeners or as Aroclor 1260 in contaminated soil. The isolate requires Desulfovibrio spp. in...

  17. Polychlorinated Biphenyls Water Pollution along the River Nile, Egypt

    Directory of Open Access Journals (Sweden)

    Ayman Mohamed Megahed

    2015-01-01

    Full Text Available Ten polychlorinated biphenyl (PCB congeners were determined in water samples collected along the River Nile using gas chromatography-electron capture detector (GC-ECD. PCB concentrations ranged from 14 to 20 μg/L, which were higher than those reported in previous studies, indicating serious PCB pollution in the River Nile. PCB congener profiles varied depending on the sampling sties. PCB-138 was the predominant congener accounting for more than 18% of total PCBs. The composition of PCB congeners in the water revealed that highly chlorinated PCB technical mixtures such as Aroclor 1254 was the main PCB production historically used in Egypt. An increasing trend in PCB levels from the upper stream to the Nile estuaries was observed. The calculated flux of PCBs indicated that 6.8 tons of PCBs is dumped into the Mediterranean Sea each year from the River Nile. The hazard quotients and carcinogenic risk caused by PCB pollution in the River Nile were above the acceptable level indicating that PCBs in the River Nile water pose adverse health effects for all age groups. Our findings revealed that PCBs possess a serious risk to the Egyptian population that depends mainly on the River Nile as a source of water. Thus, stricter legislation and regulatory controls should be applied to reduce the risk of PCBs in Egypt.

  18. Polychlorinated biphenyls and their interaction with the environment

    Energy Technology Data Exchange (ETDEWEB)

    Dickerson, K.S.; Korte, N.E.

    1994-05-01

    This document is a review of the existing technical literature regarding the physical and biological properties of polychlorinated biphenyls (PCBs) and their interaction with the environment. It is intended to be used when evaluating PCB-contaminated soil and the effects of specific environmental conditions on PCB degradation. PCBs are a class of chlorinated aromatic compounds with 209 possible structural arrangements. The composition of PCBs in the environment changes over time due to various physiochemical and biological properties and processes: vapor pressure, solubility, octanol-water partitioning, adsorption, and biodegradation. As the number of chlorine atoms increases, both vapor pressure and water solubility decrease, while adsorption and the octanol-water partitioning coefficient increase. Dechlorination of PCBs occurs primarily through aerobic and anaerobic microbial degradation. Aerobic bacteria preferentially dechlorinate less-chlorinated PCBs, while anaerobic bacteria preferentially dechlorinate more highly chlorinated PCBs. The less-chlorinated PCB congeners are less persistent in the environment due to volatilization, solubility, and aerobic biodegradation, while the more-chlorinated PCBs are more persistent in the environment due to adsorption. The composition of an original PCB mixture in the environment can be expected to change due to a combination of processes described above. Any attempt to determine the source of PCBs or Aroclors identified in an environment sample must be approached with caution to avoid inaccurate conclusions.

  19. Selective separation of hydroxy polychlorinated biphenyls (HO-PCBs) by the structural recognition on the molecularly imprinted polymers: Direct separation of the thyroid hormone active analogues from mixtures

    International Nuclear Information System (INIS)

    We developed novel separation media for hydroxy polychlorinated biphenyls (HO-PCBs) using the molecular imprinting techniques. The results of evaluation for the molecularly imprinted polymers (MIPs) by the liquid chromatography (LC) suggested that MIPs had selective separation ability for certain HO-PCB analogues. The results of the LC evaluations and molecular modeling indicated that the molecular volumes and pKa values of template molecules were related with the retention factor of HO-PCBs. Additionally, according to the detail evaluation toward the selective separation behaviors of MIPs, these HO-PCB analogues have low pKa values dependent on their chemical structures. In other words, the prepared MIPs had selective recognition ability against the analogues, which have an OH group on a phenyl carbon and two chlorine atoms on the both neighboring carbons of the carbon attached with the OH group. Moreover, these analogues may have a potential for thyroid hormone activities so that we attempted to separate these analogues directly from mixtures of HO-PCBs using a prepared MIP

  20. Aroclor 1254 exposure reduces disease resistance and innate immune responses in fasted arctic charr

    Science.gov (United States)

    Maule, A.G.; Jorgensen, E.H.; Vijayan, M.M.; Killie, J.-E.A.

    2005-01-01

    To examine the immunological impacts of polychlorinated biphenyls (PCBs) in an environmentally relevant way, we orally contaminated Arctic charr (Salvelinus alpinus) with Aroclor 1254. After contamination, fish were either fed (0 and 100 mg Aroclor 1254 kg-1 fish wt) or fasted (0, 1, 10, and 100 mg kg-1) to mimic cycles of feeding-fasting experienced by Arctic animals. After four months, PCB concentrations in muscle were the same in fasted and fed fish; however, PCBs in kidneys of fed fish were 33 to 50% of those in fasted fish. Arctic charr were exposed to Aeromonas salmonicida, the bacteria responsible for furunculosis, by cohabitation with infected conspecifics. Fasted fish had a significant trend toward lower survival with higher dose of PCBs - from 68% in controls to 48% in treatment involving 100 mg kg-1. Independent of PCB contamination, fed fish had the lowest survival; we attribute this to stress associated with establishing and maintaining feeding hierarchies. A significant decrease in the activity of lysozyme was observed in skin mucus, as was hemagglutination ability of a putative rhamnose lectin in fasted, but not in fed, PCB-treated fish. These results demonstrate the immunosuppressive effects of PCBs on Arctic charr, and they illustrate the importance of considering environmentally relevant nutritional status in ecotoxicological studies.

  1. Characterisation and fingerprinting of PCBs in flue gas and ash from waste incineration and in technical mixtures.

    Science.gov (United States)

    Jansson, Stina; Lundin, Lisa; Grabic, Roman

    2011-10-01

    Congener patterns of mono- to deca-chlorinated biphenyls (PC1-10B) were evaluated in (a) waste incineration flue gases collected in the post-combustion zone of a laboratory-scale fluidized-bed reactor, (b) ashes from two different MSW incineration plants, and (c) published data of eight Aroclor formulations. The congener patterns of the flue gases, ashes, and Aroclor mixtures clearly differed from each other, likely reflecting differences in formation pathways. The flue gas congener patterns were largely dominated by the least chlorinated congeners, whereas the ashes displayed more evenly distributed patterns. The most abundant congeners indicated a preference for 3,3',4,4'-oriented substitution, which may be related to de novo-type formation involving perylene. Principal component analysis confirmed that congener patterns differed among the three matrices and also distinguished flue gases collected at 200 °C from those collected at 300 °C and 450 °C. This distinction could be partly explained by the degree of chlorination, although the substitution status of the ortho-position, and substitution in the 3,3',4,4'-positions also seemed to be influential. Injecting biphenyl into the post-combustion zone of the reactor did not alter the patterns, indicating that availability of the backbone structure is not a limiting factor for PCB formation. PMID:21885088

  2. Polychlorinated biphenyl exposure alters the expression profile of microRNAs associated with vascular diseases.

    Science.gov (United States)

    Wahlang, Banrida; Petriello, Michael C; Perkins, Jordan T; Shen, Shu; Hennig, Bernhard

    2016-09-01

    Exposure to persistent organic pollutants, including polychlorinated biphenyls (PCBs) is correlated with multiple vascular complications including endothelial cell dysfunction and atherosclerosis. PCB-induced activation of the vasculature subsequently leads to oxidative stress and induction of pro-inflammatory cytokines and adhesion proteins. Gene expression of these cytokines/proteins is known to be regulated by small, endogenous oligonucleotides known as microRNAs that interact with messenger RNA. MicroRNAs are an acknowledged component of the epigenome, but the role of environmentally-driven epigenetic changes such as toxicant-induced changes in microRNA profiles is currently understudied. The objective of this study was to determine the effects of PCB exposure on microRNA expression profile in primary human endothelial cells using the commercial PCB mixture Aroclor 1260. Samples were analyzed using Affymetrix GeneChip® miRNA 4.0 arrays for high throughput detection and selected microRNA gene expression was validated (RT-PCR). Microarray analysis identified 557 out of 6658 microRNAs that were changed with PCB exposure (p<0.05). In-silico analysis using MetaCore database identified 21 of these microRNAs to be associated with vascular diseases. Further validation showed that Aroclor 1260 increased miR-21, miR-31, miR-126, miR-221 and miR-222 expression levels. Upregulated miR-21 has been reported in cardiac injury while miR-126 and miR-31 modulate inflammation. Our results demonstrated evidence of altered microRNA expression with PCB exposure, thus providing novel insights into mechanisms of PCB toxicity. PMID:27288564

  3. Mixture

    Directory of Open Access Journals (Sweden)

    Silva-Aguilar Martín

    2011-01-01

    Full Text Available Metals are ubiquitous pollutants present as mixtures. In particular, mixture of arsenic-cadmium-lead is among the leading toxic agents detected in the environment. These metals have carcinogenic and cell-transforming potential. In this study, we used a two step cell transformation model, to determine the role of oxidative stress in transformation induced by a mixture of arsenic-cadmium-lead. Oxidative damage and antioxidant response were determined. Metal mixture treatment induces the increase of damage markers and the antioxidant response. Loss of cell viability and increased transforming potential were observed during the promotion phase. This finding correlated significantly with generation of reactive oxygen species. Cotreatment with N-acetyl-cysteine induces effect on the transforming capacity; while a diminution was found in initiation, in promotion phase a total block of the transforming capacity was observed. Our results suggest that oxidative stress generated by metal mixture plays an important role only in promotion phase promoting transforming capacity.

  4. A routine accredited method for the analysis of polychlorinated biphenyls, organochlorine pesticides, chlorobenzenes and screening of other halogenated organics in soil, sediment and sludge by GCxGC-{mu}ECD

    Energy Technology Data Exchange (ETDEWEB)

    Muscalu, Alina M. [Ontario Ministry of the Environment, Laboratory Services Branch, Toronto, ON (Canada); University of Waterloo, Department of Chemistry, Waterloo, ON (Canada); Reiner, Eric J.; Chen, Tony; Ladwig, Gerry; Morse, David [Ontario Ministry of the Environment, Laboratory Services Branch, Toronto, ON (Canada); Liss, Steven N. [Queens University, School of Environmental Studies, Kingston, ON (Canada)

    2011-11-15

    The analysis of persistent organic pollutants is a real challenge due to the large number of compounds with varying chemical and physical properties. Gas chromatography with electron capture detection or mass spectrometry has been the method of choice for the past 50 years. Comprehensive two-dimensional gas chromatography (GCxGC) coupled with micro-electron capture detector ({mu}ECD) is a new method that can analyze polychlorinated biphenyls (PCBs), organochlorine pesticides (OCs) and chlorobenzenes (CBz) in a single analytical run with enhanced selectivity and sensitivity over single column methods and can also be used to screen for other halogenated organics in environmental samples. An accredited routine method using commercially available LECO GCxGC-{mu}ECD and a column combination DB-1 x Rtx-PCB has been developed to analyse PCBs/OCs/CBz in soils, sediments and sludges. The method provides quantification of Aroclors and Aroclor mixtures to within 15% of target values and sub-nanogrammes per gramme detection limits. (orig.)

  5. Assessing ongoing sources of dissolved-phase polychlorinated biphenyls in a contaminated stream.

    Science.gov (United States)

    Dang, Viet D; Walters, David M; Lee, Cindy M

    2013-03-01

    Few studies assess the potential of ongoing sources of "fresh" polychlorinated biphenyls (PCBs) to aquatic systems when direct discharge to the environment has been eliminated. In the present study, the authors used single-layered, low-density polyethylene samplers (PEs) to measure total PCB concentrations, congener profiles, and enantiomeric fractions (EFs) in a contaminated stream and to provide multiple lines of evidence for assessing ongoing inputs of PCB. Concentrations were well above background levels that have been monitored for years. Concentrations significantly increased with distance, the farthest downstream PE concentrations being almost five times greater than those at 79 m downstream of a historical point source. The PCBs in the PEs at 79 m downstream of the contamination source were dominated by low K(OW) congeners, similar to those in the mixture of Aroclors 1016 and 1254 (4:1 v/v) historically released from the former capacitor manufacturer. The only two chiral congeners detected in the PEs downstream were PCBs 91 and 95. The EF values were nonracemic for PCB 91, while the values were either racemic or near racemic for PCB 95. Increased PCB concentrations with distance and a congener composition of predominantly low-weight congeners in the PEs at 79 m downstream of the plant site suggested an ongoing PCB source from the plant site. Chiral signatures suggested aerobic biotransformation of dissolved PCBs but did not shed any light on possible ongoing PCB inputs. PMID:23258773

  6. Assessing ongoing sources of dissolved-phase polychlorinated biphenyls in a contaminated stream

    Science.gov (United States)

    Dang, Viet D.; Walters, David M.; Lee, Cindy M.

    2013-01-01

    Few studies assess the potential of ongoing sources of “fresh” polychlorinated biphenyls (PCBs) to aquatic systems when direct discharge to the environment has been eliminated. In the present study, the authors used single-layered, low-density polyethylene samplers (PEs) to measure total PCB concentrations, congener profiles, and enantiomeric fractions (EFs) in a contaminated stream and to provide multiple lines of evidence for assessing ongoing inputs of PCB. Concentrations were well above background levels that have been monitored for years. Concentrations significantly increased with distance, the farthest downstream PE concentrations being almost five times greater than those at 79 m downstream of a historical point source. The PCBs in the PEs at 79 m downstream of the contamination source were dominated by low KOW congeners, similar to those in the mixture of Aroclors 1016 and 1254 (4:1 v/v) historically released from the former capacitor manufacturer. The only two chiral congeners detected in the PEs downstream were PCBs 91 and 95. The EF values were nonracemic for PCB 91, while the values were either racemic or near racemic for PCB 95. Increased PCB concentrations with distance and a congener composition of predominantly low-weight congeners in the PEs at 79 m downstream of the plant site suggested an ongoing PCB source from the plant site. Chiral signatures suggested aerobic biotransformation of dissolved PCBs but did not shed any light on possible ongoing PCB inputs.

  7. Polychlorinated Biphenyls Induce Mitochondrial Dysfunction in SH-SY5Y Neuroblastoma Cells.

    Directory of Open Access Journals (Sweden)

    Stefania Cocco

    Full Text Available Chronic exposure to polychlorinated biphenyls (PCBs, ubiquitous environmental contaminants, can adversely affect the development and function of the nervous system. Here we evaluated the effect of PCB exposure on mitochondrial function using the PCB mixture Aroclor-1254 (A1254 in SH-SY5Y neuroblastoma cells. A 6-hour exposure to A1254 (5 μg/ml reduced cellular ATP production by 45%±7, and mitochondrial membrane potential, detected by TMRE, by 49%±7. Consistently, A1254 significantly decreased oxidative phosphorylation and aerobic glycolysis measured by extracellular flux analyzer. Furthermore, the activity of mitochondrial protein complexes I, II, and IV, but not V (ATPase, measured by BN-PAGE technique, was significantly reduced after 6-hour exposure to A1254. The addition of pyruvic acid during exposure to A1254 significantly prevent A1254-induced cell injury, restoring resting mitochondrial membrane potential, ATP levels, oxidative phosphorylation and aerobic glycolysis. Furthermore, pyruvic acid significantly preserved the activity of mitochondrial complexes I, II and IV and increased basal activity of complex V. Collectively, the present results indicate that the neurotoxicity of A1254 depends on the impairment of oxidative phosphorylation, aerobic glycolysis, and mitochondrial complexes I, II, and IV activity and it was counteracted by pyruvic acid.

  8. Field Analysis of Polychlorinated Biphenyls (PCBs) in Soil Using Solid-Phase Microextraction (SPME) and a Portable Gas Chromatography-Mass Spectrometry System.

    Science.gov (United States)

    Zhang, Mengliang; Kruse, Natalie A; Bowman, Jennifer R; Jackson, Glen P

    2016-05-01

    An expedited field analysis method was developed for the determination of polychlorinated biphenyls (PCBs) in soil matrices using a portable gas chromatography-mass spectrometry (GC-MS) instrument. Soil samples of approximately 0.5 g were measured with a portable scale and PCBs were extracted by headspace solid-phase microextraction (SPME) with a 100 µm polydimethylsiloxane (PDMS) fiber. Two milliliters of 0.2 M potassium permanganate and 0.5 mL of 6 M sulfuric acid solution were added to the soil matrices to facilitate the extraction of PCBs. The extraction was performed for 30 min at 100 ℃ in a portable heating block that was powered by a portable generator. The portable GC-MS instrument took less than 6 min per analysis and ran off an internal battery and helium cylinder. Six commercial PCB mixtures, Aroclor 1016, 1221, 1232, 1242, 1248, 1254, and 1260, could be classified based on the GC chromatograms and mass spectra. The detection limit of this method for Aroclor 1260 in soil matrices is approximately 10 ppm, which is sufficient for guiding remediation efforts in contaminated sites. This method was applicable to the on-site analysis of PCBs with a total analysis time of 37 min per sample. However, the total analysis time could be improved to less than 7 min per sample by conducting the rate-limiting extraction step for different samples in parallel. PMID:27170778

  9. Seasonal variability of polychlorinated biphenyls (PCBs) and polychlorinated diphenyl ethers (PBDEs) congener profiles in butter in Poland: dietary risk evaluation.

    Science.gov (United States)

    Roszko, Marek; Szymczyk, Krystyna; Rzepkowska, Małgorzata; Jędrzejczak, Renata

    2014-01-01

    Various statistical methods have been employed to analyse in details seasonal diversification of polychlorinated biphenyl (PCB)/polybrominated diphenyl ether (PBDE) congener profiles found in butter fat. The variability of the PCB/PBDE congener profiles indicates the presence of various sources of the milk fat contamination. The obtained results suggest that the environmental chemical background has the highest share in the contamination sources pattern. Ion trap mass spectrometry coupled to high-resolution gas chromatography with semi-permeable membrane dialysis sample cleanup was used for determination of PCBs and PBDEs in milk fat. Determined butter fat PCB profiles were similar to the profiles characteristic for Aroclor 1254 technical mixture. Our data indicate that dietary intake of PCB/PBDE with milk and milk products may be estimated to be about 717.5 pg kg b.w.(-1) day(-1) for six-indicator PCBs, 0.329 (equivalent toxicity, TEQ) pg kg b.w.(-1) day(-1) for 12 DL PCBs and 50 pg kg b.w.(-1) day(-1) for PBDEs (sum of 14 congeners).

  10. Polychlorinated biphenyls (PCB) analysis report for solid sample from 219S tank 101

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, L.A.

    1998-02-04

    One waste sample that was obtained with solids from tank 101 of 219S via a peristaltic pump equipped with a stainless steel tube and Norprene tubing (Phthalate free) was obtained in a glass jar with teflon lid was analyzed (with duplicate, matrix spike, and matrix spike duplicate) for PCBs as Aroclor mixtures by the Inorganic/Organic Chemistry Group. A soxhlet extraction procedure was used for extraction of the Aroclors from the sample. Analysis was performed using dual column confirmation gas chromatography/electron capture detection (GC/ECD). Results are presented.

  11. Polychlorinated biphenyls (PCB) analysis report for solid sample from 219S tank 101

    International Nuclear Information System (INIS)

    One waste sample that was obtained with solids from tank 101 of 219S via a peristaltic pump equipped with a stainless steel tube and Norprene tubing (Phthalate free) was obtained in a glass jar with teflon lid was analyzed (with duplicate, matrix spike, and matrix spike duplicate) for PCBs as Aroclor mixtures by the Inorganic/Organic Chemistry Group. A soxhlet extraction procedure was used for extraction of the Aroclors from the sample. Analysis was performed using dual column confirmation gas chromatography/electron capture detection (GC/ECD). Results are presented

  12. Isolation and characterisation of polychlorinated biphenyl (PCB degrading fungi from a historically contaminated soil

    Directory of Open Access Journals (Sweden)

    Di Toro Sara

    2009-01-01

    Full Text Available Abstract Background Polychlorinated biphenyls (PCBs are widespread toxic pollutants. Bioremediation might be an effective, cost competitive and environment-friendly solution for remediating environmental matrices contaminated by PCBs but it is still unsatisfactory, mostly for the limited biodegradation potential of bacteria involved in the processes. Very little is known about mitosporic fungi potential in PCB bioremediation and their occurrence in actual site historically contaminated soils. In the present study, we characterised the native mycoflora of an aged dump site soil contaminated by about 0.9 g kg-1 of Aroclor 1260 PCBs and its changing after aerobic biotreatment with a commercial complex source of bacteria and fungi. Fungi isolated from the soil resulting from 120 days of treatment were screened for their ability to adsorb or metabolise 3 target PCBs. Results The original contaminated soil contained low loads of few fungal species mostly belonging to the Scedosporium, Penicillium and Aspergillus genera. The fungal load and biodiversity generally decreased throughout the aerobic treatment. None of the 21 strains isolated from the treated soil were able to grow on biphenyl (200 mg L-1 or a mixture of 2-chlorobiphenyl, 4,4'-dichlorobiphenyl and 2,2',5,5'-tetrachlorobiphenyl (20 mg L-1 each as sole carbon sources. However, 16 of them grew in a mineral medium containing the same PCBs mixture and glucose (10 g L-1. Five of the 6 isolates, which displayed the faster and more extensive growth under the latter conditions, were found to degrade the 3 PCBs apparently without the involvement of ligninolytic enzymes; they were identified as Penicillium chrysogenum, Scedosporium apiospermum, Penicillium digitatum and Fusarium solani. They are the first PCB degrading strains of such species reported so far in the literature. Conclusion The native mycoflora of the actual site aged heavily contaminated soil was mainly constituted by genera often

  13. Immunological and physiological effects of chronic exposure of Peromyscus leucopus to Aroclor 1254 at a concentration similar to that found at contaminated sites

    Science.gov (United States)

    Segre, M.; Arena, S.M.; Greeley, E.H.; Melancon, M.J.; Graham, D.A.; French, J.B.

    2002-01-01

    Polychlorinated biphenyls (PCBs) are environmental contaminants known to cause adverse health effects to biological systems. Limited data are available on their effects on the immune system of wildlife species. Previously, we found that 4 and 6-week-old white-footed mice (Peromyscus leucopus) born from dams injected with a single dose (300 mg/kg) of Aroclor 1254, had altered immunological, hematological, and biochemical responses. Here, we examined the effect of transplacental lactational and postnatal exposure to Aroclor 1254, at a concentration similar to that found at contaminated sites, on various physiological parameters of 22-week-old white-footed mice. Liver weight and liver somatic index of PCB treated animals were significantly higher, the combined weights of the adrenal glands were significantly lower and EROD and BROD enzyme activity was significantly higher compared to control values. The number of thymocytes of the treated mice was significantly lower than that of the controls; however, thymocytes of treated mice had a higher proliferative response to the mitogen Con A. These alterations were correlated with the PCBs body burdens. Some toxic effects of chronic exposure to PCBs, at levels comparable to exposure found in contaminated sites in the USA, are still evident in adult P. leucopus.

  14. Radiochemical decomposition of polychlorinated biphenyls in hexane

    International Nuclear Information System (INIS)

    Products of polychlorinated biphenyls (PCB) decomposition are analyzed with the aim of determining whether polychlorinated dibenzodioxins (PCDD) or dibenzafurans (PCDF) are formed during radition-chemical decomposition. It is shown that under irradiation of PCB Arochlor 1260 mixture with 10-2 mass % concentration decomposition degree equals 90.4 % at radiaion dose more than 6 Mrad. As the result of irradiation the content of relatively light PCB in the mixture increases and the content of irradiated mixture becomes close to the content of Arochlor 1242 mixture. Neitgher PCDD nor PCDE is detected on the products of PCB decomposition

  15. Tracing the biotransformation of polychlorinated biphenyls (PCBs) in common carp (Cryprinus carpio): Enantiomeric fraction and compound-specific stable carbon isotope analyses.

    Science.gov (United States)

    Tang, Bin; Luo, Xiao-Jun; Zeng, Yan-Hong; Sun, Run-Xia; Chen, Hua-Shan; Li, Zong-Rui; Mai, Bi-Xian

    2016-09-01

    Metabolites of polychlorinated biphenyls (PCBs) in fish are difficult to detect in vivo due to the complexity of biometabolism. In the present study, atropisomeric fraction analysis of chiral PCB congeners and compound-specific isotopic analysis (CSIA) were applied to trace the biotransformation of PCBs in fish by exposure of common carp (Cryprinus carpio) to the commercial PCB mixture Aroclor 1242. Stereoselective elimination of the chiral PCB congeners 91, 95, and 136 was observed, indicating a stereoselective biotransformation process. The δ(13)C values of PCBs 5/8, 18, and 20/33 in fish were increased compared with those in the spiked food, while PCBs 47/48 and 49 showed significant heavy isotope depletion. These results suggested a significant biotransformation of the corresponding individual PCB congeners although the potential PCB metabolites, hydroxylated PCBs (OH-PCBs) and methylsulfone PCBs (MeSO2-PCBs), were not detected in the fish tissue samples throughout this experiment. The results of the present study demonstrated that a combination of chiral analysis and CSIA is a promising new approach for investigating the biotransformation of PCBs in biota. PMID:27341148

  16. Reproductive success and nest attentiveness of mallard ducks Anas platyrhynchos fed aroclor 1254

    Science.gov (United States)

    Custer, T.W.; Heinz, G.H.

    1980-01-01

    A dietary dosage of 25 ppm Aroclor 1254 fed to 9 mo. old mallards Anas platyrhynchos for at least 1 mo. before egg-laying had no detrimental effect on reproductive success or nest attentiveness when hens were allowed to incubate their own eggs. The treatment caused no effect on number of hens laying, date of 1st egg laid or clutch size. Fertility of eggs was greater among Aroclor-treated birds (87.7%) than among controls (73.2%). Aroclor may have stimulated males to come into reproductive condition sooner than controls. Hatching of fertile eggs and survival of ducklings to 3 wk of age were similar in treated and control groups. The number of times off the nest per day and total time off the nest per day were the same for control and Aroclor-treated hens in days 14-17 of incubation.

  17. Reproductive success and nest attentiveness of mallard ducks fed Aroclor 1254

    Science.gov (United States)

    Custer, T.W.; Heinz, G.H.

    1980-01-01

    A dietary dosage of 25 ppm Aroclor 1254 fed to nine-month-old mallards Anas platyrhynchos for at least a month before egg-laying had no detrimental effect on reproductive success or nest attentiveness when hens were allowed to incubate their own eggs. The treatment caused no effect on number of hens laying, date of first egg laid or clutch size. Fertility of eggs was greater among Aroclor-treated birds (87?7%) than among controls (73?2%). Aroclor may have stimulated males to come into reproductive condition sooner than controls. Hatching of fertile eggs and survival of ducklings to 3 weeks of age were similar in treated and control groups. The number of times off the nest per day and total time off the nest per day were the same for control and Aroclor-treated hens in days 14?17 of incubation.

  18. Geographic specificity of Aroclor 1268 in bottlenose dolphins (Tursiops truncatus) frequenting the Turtle/Brunswick River Estuary, Georgia (USA)

    Energy Technology Data Exchange (ETDEWEB)

    Pulster, Erin L. [Marine Sciences Department, Savannah State University, Savannah, Georgia, 31404 (United States); Skidaway Institute of Oceanography, 10 Ocean Science Circle, Savannah, Georgia, 31411 (United States)], E-mail: epulster@mote.org; Maruya, Keith A. [Skidaway Institute of Oceanography, 10 Ocean Science Circle, Savannah, Georgia, 31411 (United States)

    2008-04-15

    Coastal marine resources are at risk from anthropogenic contaminants, including legacy persistent organic pollutants (POPs) with half-lives of decades or more. To determine if polychlorinated biphenyl (PCB) signatures can be used to distinguish among local populations of inshore bottlenose dolphins (Tursiops truncatus) along the southeastern U.S. coast, blubber from free-ranging and stranded animals were collected along the Georgia coast in 2004 and analyzed for PCB congeners using gas chromatography with electron capture and negative chemical ionization mass spectrometric detection (GC-ECD and GC-NCI-MS). Mean total PCB concentrations (77 {+-} 34 {mu}g/g lipid) were more than 10 fold higher and congener distributions were highly enriched in Cl{sub 7}-Cl{sub 10} homologs in free-ranging animals from the Turtle/Brunswick River estuary (TBRE) compared with strandings samples from Savannah area estuaries 90 km to the north. Using principal components analysis (PCA), the Aroclor 1268 signature associated with TBRE animals was distinct from that observed in Savannah area animals, and also from those in animals biopsied in other southeastern U.S estuaries. Moreover, PCB signatures in dolphin blubber closely resembled those in local preferred prey fish species, strengthening the hypothesis that inshore T. truncatus populations exhibit long-term fidelity to specific estuaries and making them excellent sentinels for assessing the impact of stressors on coastal ecosystem health.

  19. Geographic specificity of Aroclor 1268 in bottlenose dolphins (Tursiops truncatus) frequenting the Turtle/Brunswick River Estuary, Georgia (USA)

    International Nuclear Information System (INIS)

    Coastal marine resources are at risk from anthropogenic contaminants, including legacy persistent organic pollutants (POPs) with half-lives of decades or more. To determine if polychlorinated biphenyl (PCB) signatures can be used to distinguish among local populations of inshore bottlenose dolphins (Tursiops truncatus) along the southeastern U.S. coast, blubber from free-ranging and stranded animals were collected along the Georgia coast in 2004 and analyzed for PCB congeners using gas chromatography with electron capture and negative chemical ionization mass spectrometric detection (GC-ECD and GC-NCI-MS). Mean total PCB concentrations (77 ± 34 μg/g lipid) were more than 10 fold higher and congener distributions were highly enriched in Cl7-Cl10 homologs in free-ranging animals from the Turtle/Brunswick River estuary (TBRE) compared with strandings samples from Savannah area estuaries 90 km to the north. Using principal components analysis (PCA), the Aroclor 1268 signature associated with TBRE animals was distinct from that observed in Savannah area animals, and also from those in animals biopsied in other southeastern U.S estuaries. Moreover, PCB signatures in dolphin blubber closely resembled those in local preferred prey fish species, strengthening the hypothesis that inshore T. truncatus populations exhibit long-term fidelity to specific estuaries and making them excellent sentinels for assessing the impact of stressors on coastal ecosystem health

  20. Congener-based analysis of the weathering of PCB Aroclor 1242 in paper mill sludge.

    Science.gov (United States)

    Saba, Tarek; Boehm, Paul D

    2011-02-01

    Aroclor 1242 contains a high percentage of lightly chlorinated congeners, which makes it susceptible to congener profile alterations as a result of physical-chemical environmental weathering by water washing, evaporation, and volatilization. The analysis of the variability of congener profiles in paper sludge samples using PCA, mixing models, and correlation (R(2)) analysis, provided an integrated description of the behavior of Aroclor 1242 after its release in the environment. The results showed that the total PCB concentration decreased as the sample experienced weathering, with the congener profile of Aroclor 1242 shifting towards resembling heavier Aroclors as lighter congeners were lost. Mixing model analysis confirmed that a sample containing weathered Aroclor 1242 could easily be misidentified by laboratories as containing a mix of heavier Aroclors. The R(2) analysis showed that the profile of the congeners within a homologue group remained the same after weathering. This analysis showed that congeners that belong to the same level of chlorination behave similarly in such a manner that retains their overall profile when exposed to physical weathering.

  1. Polychlorinated biphenyls in surface soil in urban and background areas of Mongolia

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) were measured in soil in some industrial towns (Ulaanbaatar, Suhbaatar, Erdenet, Darhan, Tsetserleg, Hovd, Ulaangom, Altay, Bayanhongor, Arvayheer, Saynshand, Choybalsan) and in background and rural areas of Mongolia. The average sum of all investigated PCB congeners in soil of Mongolia comes to 7.4 ng/g dry weight (DW) and varies from 0.53 ng/g DW till 114 ng/g DW. PCB levels in soil from towns are significantly higher than those in soil from background and rural areas. The PCB homological composition in soil sampled in highly-PCB-polluted sites is similar to the PCB homological pattern in Sovol and Aroclor 1254. Significant correlation between soil organic carbon and low chlorinated PCB both for towns and background sites was found. Significant differences in PCB means in soil in different natural zones were found. -- Highlights: •First study to measure PCBs in surface soil sampled throughout Mongolia. •The PCB patterns in polluted soil were similar to those in Sovol or Aroclor 1254. •Significant differences in PCB means in soil in different natural zones were found. -- Polychlorinated biphenyls were measured in soils throughout Mongolia

  2. Modulation of cell viability, oxidative stress, calcium homeostasis, and voltage- and ligand-gated ion channels as common mechanisms of action of (mixtures of) non-dioxin-like polychlorinated biphenyls and polybrominated diphenyl ethers

    NARCIS (Netherlands)

    Westerink, Remco H S

    2014-01-01

    Non-dioxin-like polychlorinated biphenyls (NDL-PCBs) and polybrominated diphenyl ethers (PBDEs) are environmental pollutants that exert neurodevelopmental and neurobehavioral effects in vivo in humans and animals. Acute in vitro neurotoxic effects include changes in cell viability, oxidative stress,

  3. Spatial Distribution, Air-Water Fugacity Ratios and Source Apportionment of Polychlorinated Biphenyls in the Lower Great Lakes Basin.

    Science.gov (United States)

    Khairy, Mohammed; Muir, Derek; Teixeira, Camilla; Lohmann, Rainer

    2015-12-01

    Polychlorinated biphenyls (PCBs) continue to be contaminants of concern across the Great Lakes. It is unclear whether current concentrations are driven by ongoing primary emissions from their original uses, or whether ambient PCBs are dominated by their environmental cycling. Freely dissolved PCBs in air and water were measured using polyethylene passive samplers across Lakes Erie and Ontario during summer and fall, 2011, to investigate their spatial distribution, determine and apportion their sources and to asses their air-water exchange gradients. Average gaseous and freely dissolved ∑29 PCB concentrations ranged from 5.0 to 160 pg/m(3) and 2.0 to 55 pg/L respectively. Gaseous concentrations were significantly correlated (R(2) = 0.80) with the urban area within a 3-20 km radius. Fugacity ratios indicated that the majority of PCBs are volatilizing from the water thus acting as a secondary source for the atmosphere. Dissolved PCBs were probably linked to PCB emissions from contaminated sites and areas of concern. Positive matrix factorization indicated that although volatilized Aroclors (gaseous PCBs) and unaltered Aroclors (dissolved PCBs) dominate in some samples, ongoing non-Aroclor sources such as paints/pigments (PCB 11) and coal/wood combustion showed significant contributions across the lower Great Lakes. Accordingly, control strategies should give further attention to PCBs emitted from current use sources.

  4. Spatial Distribution, Air-Water Fugacity Ratios and Source Apportionment of Polychlorinated Biphenyls in the Lower Great Lakes Basin.

    Science.gov (United States)

    Khairy, Mohammed; Muir, Derek; Teixeira, Camilla; Lohmann, Rainer

    2015-12-01

    Polychlorinated biphenyls (PCBs) continue to be contaminants of concern across the Great Lakes. It is unclear whether current concentrations are driven by ongoing primary emissions from their original uses, or whether ambient PCBs are dominated by their environmental cycling. Freely dissolved PCBs in air and water were measured using polyethylene passive samplers across Lakes Erie and Ontario during summer and fall, 2011, to investigate their spatial distribution, determine and apportion their sources and to asses their air-water exchange gradients. Average gaseous and freely dissolved ∑29 PCB concentrations ranged from 5.0 to 160 pg/m(3) and 2.0 to 55 pg/L respectively. Gaseous concentrations were significantly correlated (R(2) = 0.80) with the urban area within a 3-20 km radius. Fugacity ratios indicated that the majority of PCBs are volatilizing from the water thus acting as a secondary source for the atmosphere. Dissolved PCBs were probably linked to PCB emissions from contaminated sites and areas of concern. Positive matrix factorization indicated that although volatilized Aroclors (gaseous PCBs) and unaltered Aroclors (dissolved PCBs) dominate in some samples, ongoing non-Aroclor sources such as paints/pigments (PCB 11) and coal/wood combustion showed significant contributions across the lower Great Lakes. Accordingly, control strategies should give further attention to PCBs emitted from current use sources. PMID:25915412

  5. Occupational exposure to polychlorinated biphenyls in electrical workers. I. Environmental and blood polychlorinated biphenyls concentrations.

    OpenAIRE

    Maroni, M; Colombi, A.; Cantoni, S; Ferioli, E; Foa, V

    1981-01-01

    Industrial exposure to polychlorinated biphenyls (PCBs) and internal dose were investigated in 80 worker exposed for many years to PCB mixtures with a 42% chlorine content (Pyralene 3010 and Apirolio). PCBs were determined by liquid gas chromatography on samples taken from workroom air, workroom surfaces and tools, the palms of the hand, and the blood of the workers. In the workroom air samples, PCB concentrations ranged from 48 to 275 micrograms/m3. All tested surfaces and tools were heavily...

  6. Effects of perinatal coexposure to methylmercury and polychlorinated biphenyls on neurobehavioral development in mice

    Energy Technology Data Exchange (ETDEWEB)

    Sugawara, Norio [Tohoku University School of Medicine, Environmental Health Sciences, Aoba-ku, Sendai (Japan); Hirosaki University Graduate School of Medicine, Department of Neuropsychiatry, Hirosaki (Japan); Ohba, Takashi; Nakai, Kunihiko; Nakamura, Tomoyuki; Suzuki, Keita; Kameo, Satomi; Shimada, Miyuki; Kurokawa, Naoyuki; Satoh, Chieko; Satoh, Hiroshi [Tohoku University School of Medicine, Environmental Health Sciences, Aoba-ku, Sendai (Japan); Kakita, Akiyoshi [Niigata University, Department of Pathological Neuroscience, Resource Branch for Brain Disease Research, Brain Research Institute, Niigata (Japan)

    2008-06-15

    Methylmercury (MeHg) and polychlorinated biphenyls (PCBs) are environmental pollutants that cause neurobehavioral deficits in humans. Because exposures to MeHg and PCBs occur through fish consumption, it is necessary to clarify the effects of the interaction of the two pollutants. Therefore, we investigated the effects of perinatal exposure to MeHg and PCBs on the neurobehavioral development in mice. Female mice (C57BL/6Cr) were divided into four groups according to the type of exposure: (1) vehicle control, (2) MeHg alone, (3) PCBs alone, and (4) MeHg + PCBs. The MeHg-exposed groups were fed with a diet containing 5 ppm MeHg (as Hg), from 4 weeks before mating, throughout pregnancy, and lactation. The PCB-exposed groups were given a commercial mixture of PCBs, Aroclor 1254, at 18 mg/kg body weight in corn oil by gavage every 3 days from day 5 after breeding and continued until postnatal day (PND) 20. Before weaning, an assessment of eye opening showed the interactive effects between MeHg and PCBs on PND 12: The coexposure group showed a similar response to the control group, whereas the MeHg- and PCB-exposed groups showed a high response than the former two groups. We also observed delay in development of grasp reflex by MeHg exposure on PNDs 12 and 14. When the offspring mice were 8 weeks old, the group exposed to PCBs alone showed increases in the frequencies of excrement defecation and urine traces in an open-field test. Analysis of the latency revealed the antagonistic interaction between the MeHg and PCBs: The latency increased by either MeHg or PCB exposure was decreased by coexposure. Treatment with MeHg decreased the distance walked by the mice, and MeHg interacted with PCBs. Moris' water maze test showed that the MeHg-treated mice took a long time to reach the submerged platform; however, this MeHg exposure showed no interaction with PCB exposure. The spontaneous locomotion activity of the mice was not affected by the chemical exposure at 9 weeks of

  7. Aqueous exposure to Aroclor 1254 modulates the mitogenic response of Atlantic salmon anterior kidney T-cells: Indications of short- and long-term immunomodulation

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) exist as persistent organic pollutants in numerous river systems in the United States. Unfortunately, some of these rivers are sites of active Atlantic salmon restoration programs, and polychlorinated biphenyls have been implicated as ancillary factors contributing to failed salmon restoration. Here, we investigate the immediate and chronic effects of intermediate duration aqueous PCB exposure (1 or 10 μg L-1 Aroclor 1254) on the mitogen-stimulated lymphoproliferative response of Atlantic salmon anterior kidney leukocytes (AKLs). A short-term study was designed to examine immunomodulation in Atlantic salmon smolts immediately following 21 days of aqueous exposure, while a long-term study evaluated chronic impacts in the mitogen response in parr 15 months post-exposure as larvae. The proliferative response of AKLs to the mitogens concanavalin A (CON A), phytohemaglutinnin-P (PHA-P), pokeweed mitogen (PWM), and lipopolysaccharide were used as an indice of immunomodulation. The proliferative response to the T-cell mitogens CON A and PHA-P was significantly increased in the 10 μg L-1 group (n = 10; P = 0.043 and 0.002, respectively) immediately following exposure of smolts. Additionally, The PHA-P response was significantly increased in the 1 μg L-1 exposure group (n = 10, P = 0.036). In fish treated as larvae and tested 15 months later, the PHA-P sensitive populations exhibited elevated proliferation in the 1 and 10 μg L-1 groups (n = 12, P -1 treated groups. These results demonstrate an immunomodulatory effect of PCBs on T-cell mitogen sensitive populations of lymphocytes in Atlantic salmon as well as long-term immunomodulation in PHA-P and PWM sensitive populations

  8. Accumulation of polychlorinated biphenyls in turbot (Scophthalmus maximus) from seawater sediments and food

    Science.gov (United States)

    Courtney, W. A. M.; Langston, W. J.

    1980-03-01

    Juvenile turbot, Scophthalmus maximus (L.), were exposed to 0.58 µg 1-1 Aroclor 1254 in seawater, to sediments containing 100, 60 and 1 ppm or fed with cockle containing 20 ppm PCB (polychlorinated biphenyls). Concentration factors for liver and muscle were 104 and 103, respectively, for uptake of PCB from seawater. Contamination of muscle was similar to that of sediments containing 1 and 60 ppm PCB to which turbot were exposed, but less than the 20 ppm in their experimental diet. Contamination of flatfish in the North Sea area is compared with the levels of PCB in the flounder, Platichthys flesus (L.), in the River Thames and predictable values for uptake of PCB from different pathways discussed.

  9. Effect of polychlorinated biphenyls on spermatogenesis and testosterone secretion in adult cocks

    Institute of Scientific and Technical Information of China (English)

    张才乔; 乔惠理

    2004-01-01

    The effects ofpolychlorinated biphenyls (PCBs) on reproduction of adult cocks were studied by gavaging peanut oil or PCBs (Aroclor 1254, 50 mg/kg) once a week for six consecutive weeks. Physiological parameters were recorded and gonads were removed at the end of experiment for histological examination. The results showed that there was no significant difference between the control and treatment group in body weight, respiration rate, heart rate, body temperature, and the numbers of red and white blood cells. However, there was a marked decrease in the testicular weight and serum testosterone level after PCB treatment. Morphological studies manifested severe damage of the seminiferous tubules by PCB. The number of the germ cells at the different developmental stages was decreased and condensed nuclei were observed in most of these cells. This study revealed that the reproductive function of the adult cocks is sensitive to PCBs, which inhibited mainly spermatogenesis and testosterone secretion.

  10. Reproduction success of American kestrels exposed to dietary polychlorinated biphenyls.

    Science.gov (United States)

    Fernie, K J; Smits, J E; Bortolotti, G R; Bird, D M

    2001-04-01

    While reproduction of wild birds is adversely affected by multiple environmental contaminants, we determined that polychlorinated biphenyls (PCBs) alone alter reproduction. Captive American kestrels (Falco sparverius), fed PCB-spiked (Aroclor 1248:1254:1260) food (7 mg/kg body weight/d) prior to and during the first breeding season only (100 d) laid eggs with environmentally relevant levels of total PCBs (34.0 microg/g whole egg wet wt vs 0 microg/g for controls). Reproduction changed during, not after, PCB exposure in this two-year study. The PCB-exposed pairs laid smaller clutches later in the season and laid more totally infertile clutches. Hatching success was reduced in PCB-exposed pairs, and 50% of PCB nestlings died within 3 d of hatching. Nearly 60% of PCB-exposed pairs with hatchlings failed to produce fledglings. Higher levels of total PCB residues and congeners were associated with later clutch initiation and fewer fertile eggs, hatchlings, and fledglings. We suggest that nonpersistent PCB congeners have a greater influence on reproduction than do persistent congeners. PMID:11345453

  11. Thermic decomposition of biphenyl

    International Nuclear Information System (INIS)

    Liquid and vapour phase pyrolysis of very pure biphenyl obtained by methods described in the text was carried out at 400 C in sealed ampoules, the fraction transformed being always less than 0.1 per cent. The main products were hydrogen, benzene, terphenyls, and a deposit of polyphenyls strongly adhering to the walls. Small quantities of the lower aliphatic hydrocarbons were also found. The variation of the yields of these products with a) the pyrolysis time, b) the state (gas or liquid) of the biphenyl, and c) the pressure of the vapour was measured. Varying the area and nature of the walls showed that in the absence of a liquid phase, the pyrolytic decomposition takes place in the adsorbed layer, and that metallic walls promote the reaction more actively than do those of glass (pyrex or silica). A mechanism is proposed to explain the results pertaining to this decomposition in the adsorbed phase. The adsorption seems to obey a Langmuir isotherm, and the chemical act which determines the overall rate of decomposition is unimolecular. (author)

  12. Sexual difference in gonadal development of embryonic chickens after treatment of polychlorinated biphenyls

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitous, persistent and lipophilic environmental endocrine disrupters that can be biomagnified in human and animals including birds and thus to affect reproductive functions.Poultry meat and eggs contain a great deal of fat and possibly concentrate higher PCBs and other environmental contaminants such as dichlorodiphenyl-trichloroethane (DDT).In order to identify the adverse effects of PCBs and possible sexual difference on chicken gonadal development, Aroclor 1254 was injected into fertilized Hyline chicken eggs before incubation. Four groups of eggs received yolk injection of either peanut oil as control, 1, 10 or 100 μg/egg of Aroclor 1254 as treatment group, respectively. After hatching the gonads were removed for histological examination. Testicular structure was apparently changed and exhibited dramatic decrease in area of the transverse sections (1 μg/egg, P< 0.01; 10 and 100 μg/egg, P<0.001), diameter (10 and 100 μg/egg, P <0.05) and relative area of the testicular tubules (10 μg/egg, P<0.05; 100 μg/egg, P<0.01). Most testicular tubules of the highest dose group degenerated and even disappeared. The differentiation of germ cells was retarded in all groups treated with Aroclor 1254. Some germ cells were irregular in shape, with vacuolated cytoplasm and hyperchromatism nucleus (pyknosis) in 1 and 10 μg/egg groups and almost all germ cells in 100 μg/egg group. In contrast,the area of the left ovarian transverse sections increased dramatically (10 and 100 lμg/egg, P <0.001), the ovarian cortex manifested a significant increment in thickness (1, 10 and 100 μg/egg, P <0.001) and a higher number of oocytes was observed (1, 10 and 100 μg/egg, P <0.001) in the female chickens treated with Aroclor 1254 compared with the control group. A few oocytes with vacuolated cytoplasm and hyperchromatic nucleus were also observed in ovarian cortex after PCBs exposure. These results showed that PCBs interfered

  13. Polychlorinated biphenyls (PCBs) and neurological development in children: a systematic review

    OpenAIRE

    Ribas-Fito, N; Sala, M.; Kogevinas, M; Sunyer, J.

    2001-01-01

    BACKGROUND—Polychlorinated biphenyls (PCBs) are complex mixtures of persistent contaminants that are widespread in the environment. Newborns are exposed across the placenta and through breast feeding. Experimental animal studies have indicated that PCBs are neurotoxic. The neurological effects of these compounds on children are not clear. Methods—A systematic review of literature on the relation between neurological development in children and exposure to polychlorinated biphenyls.
RESULTS—Se...

  14. Proteomic strategy for the analysis of the polychlorobiphenyl-degrading cyanobacterium Anabaena PD-1 exposed to Aroclor 1254.

    Science.gov (United States)

    Zhang, Hangjun; Jiang, Xiaojun; Xiao, Wenfeng; Lu, Liping

    2014-01-01

    The cyanobacterium Anabaena PD-1, which was originally isolated from polychlorobiphenyl (PCB)-contaminated paddy soils, has capabilities for dechlorinatin and for degrading the commercial PCB mixture Aroclor 1254. In this study, 25 upregulated proteins were identified using 2D electrophoresis (2-DE) coupled with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). These proteins were involved in (i) PCB degradation (i.e., 3-chlorobenzoate-3,4-dioxygenase); (ii) transport processes [e.g., ATP-binding cassette (ABC) transporter substrate-binding protein, amino acid ABC transporter substrate-binding protein, peptide ABC transporter substrate-binding protein, putrescine-binding protein, periplasmic solute-binding protein, branched-chain amino acid uptake periplasmic solute-binding protein, periplasmic phosphate-binding protein, phosphonate ABC transporter substrate-binding protein, and xylose ABC transporter substrate-binding protein]; (iii) energetic metabolism (e.g., methanol/ethanol family pyrroloquinoline quinone (PQQ)-dependent dehydrogenase, malate-CoA ligase subunit beta, enolase, ATP synthase β subunit, FOF1 ATP synthase subunit beta, ATP synthase α subunit, and IMP cyclohydrolase); (iv) electron transport (cytochrome b6f complex Fe-S protein); (v) general stress response (e.g., molecular chaperone DnaK, elongation factor G, and translation elongation factor thermostable); (vi) carbon metabolism (methanol dehydrogenase and malate-CoA ligase subunit beta); and (vii) nitrogen reductase (nitrous oxide reductase). The results of real-time polymerase chain reaction showed that the genes encoding for dioxygenase, ABC transporters, transmembrane proteins, electron transporter, and energetic metabolism proteins were significantly upregulated during PCB degradation. These genes upregulated by 1.26- to 8.98-fold. These findings reveal the resistance and adaptation of cyanobacterium to the presence of PCBs, shedding light on the

  15. Proteomic strategy for the analysis of the polychlorobiphenyl-degrading cyanobacterium Anabaena PD-1 exposed to Aroclor 1254.

    Directory of Open Access Journals (Sweden)

    Hangjun Zhang

    Full Text Available The cyanobacterium Anabaena PD-1, which was originally isolated from polychlorobiphenyl (PCB-contaminated paddy soils, has capabilities for dechlorinatin and for degrading the commercial PCB mixture Aroclor 1254. In this study, 25 upregulated proteins were identified using 2D electrophoresis (2-DE coupled with matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS. These proteins were involved in (i PCB degradation (i.e., 3-chlorobenzoate-3,4-dioxygenase; (ii transport processes [e.g., ATP-binding cassette (ABC transporter substrate-binding protein, amino acid ABC transporter substrate-binding protein, peptide ABC transporter substrate-binding protein, putrescine-binding protein, periplasmic solute-binding protein, branched-chain amino acid uptake periplasmic solute-binding protein, periplasmic phosphate-binding protein, phosphonate ABC transporter substrate-binding protein, and xylose ABC transporter substrate-binding protein]; (iii energetic metabolism (e.g., methanol/ethanol family pyrroloquinoline quinone (PQQ-dependent dehydrogenase, malate-CoA ligase subunit beta, enolase, ATP synthase β subunit, FOF1 ATP synthase subunit beta, ATP synthase α subunit, and IMP cyclohydrolase; (iv electron transport (cytochrome b6f complex Fe-S protein; (v general stress response (e.g., molecular chaperone DnaK, elongation factor G, and translation elongation factor thermostable; (vi carbon metabolism (methanol dehydrogenase and malate-CoA ligase subunit beta; and (vii nitrogen reductase (nitrous oxide reductase. The results of real-time polymerase chain reaction showed that the genes encoding for dioxygenase, ABC transporters, transmembrane proteins, electron transporter, and energetic metabolism proteins were significantly upregulated during PCB degradation. These genes upregulated by 1.26- to 8.98-fold. These findings reveal the resistance and adaptation of cyanobacterium to the presence of PCBs, shedding light on the

  16. Research progress of the endocrine disrupting activities of polychlorinated biphenyls

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jingming; QIN Zhanfen; CONG Lin; XU Xiaobai

    2004-01-01

    Polychlorinated biphenyls (PCBs) are global persistent organic pollutants. Almost all commercial PCBs mixtures, single PCB congener, and their metabolites possess endocrine disrupting activities. They can disrupt the estrogen/androgen system, thyroid hormone system and other endocrine systems by interfering with the synthesis, transport, storage, metabolism, and feedback regulation of hormones. The newest data related to the endocrine disrupting activities of PCBs and their mechanisms are reviewed and the research perspectives are also discussed.

  17. K Basin sludge polychlorinated biphenyl removal technology assessment

    International Nuclear Information System (INIS)

    The two Hanford K Basins are water-filled concrete pools that contain over 2,100 metric tons of N Reactor fuel elements stored in aluminum or stainless steel canisters. During the time the fuel has been stored, approximately 50 m3 of heterogeneous solid material have accumulated in the basins. This material, referred to as sludge, is a mixture of fuel corrosion products, metallic bits of spent fuel and zirconium clad iron and metal corrosion products and silica from migrating sands. Some of the sludges also contain PCBs. The congener group of PCBs was identified as Aroclor 1254. The maximum concentration of sludge PCBS was found to be 140 ppm (as settled wet basis). However, the distribution of the PCBs is non-uniform throughout the sludge (i.e., there are regions of high and low concentrations and places where no PCBs are present). Higher concentrations could be present at various locations. Aroclors 1016/1242, 1221, 1248, 1254, and 1260 were identified and quantified in K West (KW) Canister sludge. In some of these samples, the concentration of 1260 was higher than 1254. The sludge requires pre-treatment to meet tank farm waste acceptance criteria, Among the numerous requirements, the sludge should be retreated so that it does not contain regulated levels of Toxic Substances Control Act (TSCA) compounds. Because of their stable chemistry and relative insolubility in water, PCBs are difficult to treat. They also resist degradation from heat and electrical charges. This stability has resulted in environmental persistence which has prompted the development of a variety of new cleanup processes including supercritical processes, advanced oxidation, dehalogenation and others. Hopefully, most of the new processes are discussed herein. Information on new processes are being received and will be evaluated in a future revision

  18. K Basin sludge polychlorinated biphenyl removal technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ashworth, S.C.

    1998-08-25

    The two Hanford K Basins are water-filled concrete pools that contain over 2,100 metric tons of N Reactor fuel elements stored in aluminum or stainless steel canisters. During the time the fuel has been stored, approximately 50 m3 of heterogeneous solid material have accumulated in the basins. This material, referred to as sludge, is a mixture of fuel corrosion products, metallic bits of spent fuel and zirconium clad iron and metal corrosion products and silica from migrating sands. Some of the sludges also contain PCBs. The congener group of PCBs was identified as Aroclor 1254. The maximum concentration of sludge PCBS was found to be 140 ppm (as settled wet basis). However, the distribution of the PCBs is non-uniform throughout the sludge (i.e., there are regions of high and low concentrations and places where no PCBs are present). Higher concentrations could be present at various locations. Aroclors 1016/1242, 1221, 1248, 1254, and 1260 were identified and quantified in K West (KW) Canister sludge. In some of these samples, the concentration of 1260 was higher than 1254. The sludge requires pre-treatment to meet tank farm waste acceptance criteria, Among the numerous requirements, the sludge should be retreated so that it does not contain regulated levels of Toxic Substances Control Act (TSCA) compounds. Because of their stable chemistry and relative insolubility in water, PCBs are difficult to treat. They also resist degradation from heat and electrical charges. This stability has resulted in environmental persistence which has prompted the development of a variety of new cleanup processes including supercritical processes, advanced oxidation, dehalogenation and others. Hopefully, most of the new processes are discussed herein. Information on new processes are being received and will be evaluated in a future revision.

  19. Profile of polychlorinated biphenyls in the brown alga Padina sanctae-crucis along the Orote dump coastline, Orote Peninsula, Western Guam.

    Science.gov (United States)

    Schaible, Brian Christopher

    2010-01-01

    The purpose of this study was to determine whether the brown seaweed Padina sanctae-crucis might be used as a biomonitor organism to determine the location, distribution, and type of polychlorinated biphenyls (PCB) present along a contaminated tropical coastline. Polychlorinated biphenyls were detected in P. sanctae-crucis collected from near-shore waters along a 4-km stretch of coastline. The profile of PCB levels from samples obtained at 13 sites along the coastline demonstrated a positive concentration gradient as sample locations progressed toward the dump site. Sample locations nearest the dump site revealed PCB levels twofold higher than background levels for P. sanctae-crucis. Chromatograms of samples obtained nearest the dump site indicated a similarity to the Aroclor 1260 fingerprint. The P. sanctae-crucis frond trimmings used for laboratory analysis were approximately 3-5 wk old. This study was conducted 8 mo following the completion of the removal actions at the dump site. Data suggest a release of Aroclor 1260 into the marine environment approximately 7 mo following the completion of removal actions at the dump site.

  20. Triglyceride accumulation in long-term cultures of adult rat hepatocytes by chronic exposure to Aroclor 1254

    International Nuclear Information System (INIS)

    The effect of chronic exposure to micromolar concentrations of Aroclor 1254 (Aro) on the hepatic lipid metabolism was studied in long-term cultures of adult rat hepatocytes. Hepatocytes were cocultivated with mytomicin C-treated 3T3 cells and exposed for 2 wk to Aroclor 1254 concentrations ranging from 0.01 to 20 μg/ml. The Aro-exposed cultures showed intracytoplasmic lipid droplets and a maximum increase of 55% in the triglyceride (TG) content and of 4.4-fold in the cytochrome P-450 content. Labeling studies with [14C]acetic and [14C]oleic acid showed no changes in the uptake of fatty acid and TG precursors by the Aro-treated cultures; the synthesis of cellular lipids from [14C]acetic acid was slightly inhibited by Aroclor 1254, but that from [14C]oleic acid was increased, specially for TF (37%). The secretion of total lipids and TG was 2.1- and 2.7-fold lower, respectively, in the cultures treated with 20 μg/ml of Aroclor 1254, resulting in an increase of 1.9-fold in the intracellular content of TG. The synthesis of cellular proteins labeled with [3H]leucine was unchanged in the Aro-treated cultures, but the secretion of exportable proteins was 1.7-fold lower in the cultures treated with 20 μg/ml of Aroclor 1254. Our results showed that long-term exposure to in vivo relevant concentrations of Aroclor 1254 produced morphological and biochemical changes in cultured hepatocytes, like those described in vivo, and intracellular TG accumulation due mostly to impaired secretion of TG by the hepatocytes. Our results also suggest that this culture system could be useful for the screening of toxic agents producing fatty liver and the study of the involved mechanism(s)

  1. Degradation of polychlorinated biphenyls

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCB) are generally disposed of by incineration, an expensive and hazardous method. Moreover, in cases where the PCBs are a minor component of a nontoxic fluid, such as a dielectric fluid, incineration causes loss of the nontoxic fluid as well as the PCB. An alternative method for destroying PCBs is disclosed which is not only capable of detoxification of PCB-contaminated soils, sludges, and sediments, but can also remove PCBs from solution in a wide range of concentrations, permitting full recovery of the bulk of the solution free of PCBs. The process of the invention may be operated in a batch, continuous, or semicontinuous mode, and is advantageously used to detoxify organic liquids such as transformer oils. According to the invention, PCBs are chemically degraded by contact with a Lewis acid catalyst in a nonaqueous liquid medium, in the presence of a cation which combines with the chlorine on the PCB to form a solid chloride of the cation which will precipitate out from the liquid medium. Preferred Lewis acids are metal halides, particularly a combination of aluminum chloride and ferric chloride, and the preferred cation is potassium in the form of KOH. The Lewis acids may be supplied to the process by the adventitious corrosion of a vessel containing the PCB-contaminated matter. Experiments are described to illustrate the process of the invention. 3 figs

  2. Arbuscular Mycorrhizal Fungal Hyphae Alter Soil Bacterial Community and Enhance Polychlorinated Biphenyls Dissipation

    Science.gov (United States)

    Qin, Hua; Brookes, Philip C.; Xu, Jianming

    2016-01-01

    We investigated the role of arbuscular mycorrhizal fungal (AMF) hyphae in alternation of soil microbial community and Aroclor 1242 dissipation. A two-compartment rhizobox system with double nylon meshes in the central was employed to exclude the influence of Cucurbita pepo L. root exudates on hyphal compartment soil. To assess the quantitative effect of AMF hyphae on soil microbial community, we separated the hyphal compartment soil into four horizontal layers from the central mesh to outer wall (e.g., L1–L4). Soil total PCBs dissipation rates ranged from 35.67% of L4 layer to 57.39% of L1 layer in AMF inoculated treatment, which were significant higher than the 17.31% of the control (P biphenyls as well as the total PCBs were significantly correlated with soil hyphal length (P biphenyl dissipation, while taxa from the Oxalobacteraceae and Streptomycetaceae responded negatively to AMF and PCB congener dissipation. Our results suggested that the AMF hyphal exudates as well as the hyphae per se did have quantitative effects on shaping soil microbial community, and could modify the PCBs dissipation processes consequently. PMID:27379068

  3. BEHAVIORAL EVALUATION OF PERINATAL EXPOSURE TO AROCLOR 1254 IN RATS: FIXED-INTERVAL PERFORMANCE AND REINFORCEMENT-OMISSION.

    Science.gov (United States)

    Mele et al. (1986) reported exposure to Aroclor 1248 (A1248) in rhesus monkeys produced an increased rate of responding under a fixed-interval (FI) schedule of reinforcement in which 25% of the scheduled reinforcers were omitted. The purpose of this work was to determine whether...

  4. Biodegradation of polychlorinated biphenyls (PCBs by the novel identified cyanobacterium Anabaena PD-1.

    Directory of Open Access Journals (Sweden)

    Hangjun Zhang

    Full Text Available Polychlorinated biphenyls (PCBs, a class of hazardous pollutants, are difficult to dissipate in the natural environment. In this study, a cyanobacterial strain Anabaena PD-1 showed good resistance against PCB congeners. Compared to a control group, chlorophyll a content decreased 3.7% and 11.7% when Anabaena PD-1 was exposed to 2 and 5 mg/L PCBs for 7 d. This cyanobacterial strain was capable of decomposing PCB congeners which was conclusively proved by determination of chloride ion concentrations in chlorine-free medium. After 7 d, the chloride ion concentrations in PCB-treated groups (1, 2, 5 mg/L were 3.55, 3.05, and 2.25 mg/L, respectively. The genetic information of strain PD-1 was obtained through 16S rRNA sequencing analysis. The GenBank accession number of 16S rRNA of Anabaena PD-1 was KF201693.1. Phylogenetic tree analysis clearly indicated that Anabaena PD-1 belonged to the genus Anabaena. The degradation half-life of Aroclor 1254 by Anabaena PD-1 was 11.36 d; the total degradation rate for Aroclor 1254 was 84.4% after 25 d. Less chlorinated PCB congeners were more likely to be degraded by Anabaena PD-1 in comparison with highly chlorinated congeners. Meta- and para-chlorines in trichlorodiphenyls and tetrachlorobiphenyls were more susceptible to dechlorination than ortho-chlorines during the PCB-degradation process by Anabaena PD-1. Furthermore, Anabaena PD-1 can decompose dioxin-like PCBs. The percent biodegradation of 12 dioxin-like PCBs by strain PD-1 ranged from 37.4% to 68.4% after 25 days. Results above demonstrate that Anabaena PD-1 is a PCB-degrader with great potential for the in situ bioremediation of PCB-contaminated paddy soils.

  5. Biodegradation of polychlorinated biphenyls (PCBs) by the novel identified cyanobacterium Anabaena PD-1.

    Science.gov (United States)

    Zhang, Hangjun; Jiang, Xiaojun; Lu, Liping; Xiao, Wenfeng

    2015-01-01

    Polychlorinated biphenyls (PCBs), a class of hazardous pollutants, are difficult to dissipate in the natural environment. In this study, a cyanobacterial strain Anabaena PD-1 showed good resistance against PCB congeners. Compared to a control group, chlorophyll a content decreased 3.7% and 11.7% when Anabaena PD-1 was exposed to 2 and 5 mg/L PCBs for 7 d. This cyanobacterial strain was capable of decomposing PCB congeners which was conclusively proved by determination of chloride ion concentrations in chlorine-free medium. After 7 d, the chloride ion concentrations in PCB-treated groups (1, 2, 5 mg/L) were 3.55, 3.05, and 2.25 mg/L, respectively. The genetic information of strain PD-1 was obtained through 16S rRNA sequencing analysis. The GenBank accession number of 16S rRNA of Anabaena PD-1 was KF201693.1. Phylogenetic tree analysis clearly indicated that Anabaena PD-1 belonged to the genus Anabaena. The degradation half-life of Aroclor 1254 by Anabaena PD-1 was 11.36 d; the total degradation rate for Aroclor 1254 was 84.4% after 25 d. Less chlorinated PCB congeners were more likely to be degraded by Anabaena PD-1 in comparison with highly chlorinated congeners. Meta- and para-chlorines in trichlorodiphenyls and tetrachlorobiphenyls were more susceptible to dechlorination than ortho-chlorines during the PCB-degradation process by Anabaena PD-1. Furthermore, Anabaena PD-1 can decompose dioxin-like PCBs. The percent biodegradation of 12 dioxin-like PCBs by strain PD-1 ranged from 37.4% to 68.4% after 25 days. Results above demonstrate that Anabaena PD-1 is a PCB-degrader with great potential for the in situ bioremediation of PCB-contaminated paddy soils.

  6. Polychlorinated biphenyl (PCB) exposure assessment by multivariate statistical analysis of serum congener profiles in an adult Native American population.

    Science.gov (United States)

    DeCaprio, Anthony P; Johnson, Glenn W; Tarbell, Alice M; Carpenter, David O; Chiarenzelli, Jeffrey R; Morse, Gayle S; Santiago-Rivera, Azara L; Schymura, Maria J

    2005-07-01

    The major determinants of human polychlorinated biphenyl (PCB) body burden include the source and route of exposure and the toxicokinetic processes occurring after uptake. However, the relative importance of each factor for individual subjects cannot currently be determined. The present study characterizes levels and patterns of PCB congeners in a large cohort of adult Akwesasne Mohawks with historical PCB exposure. Total serum PCB ranged from 0.29 to 48.32 ng/g and was higher in adult men than in women (median of 3.81 vs. 2.94 ng/g). The mean serum congener profile for the full cohort was dominated by persistent penta- to hepta-chlorinated biphenyls; several labile congeners were also prominent. In order to provide additional information on individual body burden determinants, multivariate exploratory data analysis techniques were applied to the congener-specific serum PCB data. A self-training receptor model, polytopic vector analysis (PVA), was employed to determine the number, composition, and relative proportions of independent congener patterns that contributed to the overall serum PCB profile for each Mohawk subject. PVA identified five such patterns, each of which was characterized by a unique mix of congeners. One pattern observed in a limited number of Mohawks was similar to those reported for air sampled near contaminated sediment deposits at Akwesasne and for volatilized Aroclor 1248 and is hypothesized to reflect recent inhalation exposure in these subjects. A second pattern was consistent with unaltered Aroclor 1254. A third pattern, resembling Aroclor 1262 but without labile congeners, was correlated with age and is interpreted as representing a lifetime PCB accumulation profile. The final two patterns were dominated by subsets of major persistent congeners and are hypothesized to reflect intermediate bioaccumulation profiles and/or differences in individual toxicokinetics. The results confirm the utility of a multivariate exploratory analysis

  7. Thermic decomposition of biphenyl; Decomposition thermique du biphenyle

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1966-03-01

    Liquid and vapour phase pyrolysis of very pure biphenyl obtained by methods described in the text was carried out at 400 C in sealed ampoules, the fraction transformed being always less than 0.1 per cent. The main products were hydrogen, benzene, terphenyls, and a deposit of polyphenyls strongly adhering to the walls. Small quantities of the lower aliphatic hydrocarbons were also found. The variation of the yields of these products with a) the pyrolysis time, b) the state (gas or liquid) of the biphenyl, and c) the pressure of the vapour was measured. Varying the area and nature of the walls showed that in the absence of a liquid phase, the pyrolytic decomposition takes place in the adsorbed layer, and that metallic walls promote the reaction more actively than do those of glass (pyrex or silica). A mechanism is proposed to explain the results pertaining to this decomposition in the adsorbed phase. The adsorption seems to obey a Langmuir isotherm, and the chemical act which determines the overall rate of decomposition is unimolecular. (author) [French] Du biphenyle tres pur, dont la purification est decrite, est pyrolyse a 400 C en phase vapeur et en phase liquide dans des ampoules scellees sous vide, a des taux de decomposition n'ayant jamais depasse 0,1 pour cent. Les produits provenant de la pyrolyse sont essentiellement: l' hydrogene, le benzene, les therphenyles, et un depot de polyphenyles adherant fortement aux parois. En plus il se forme de faibles quantites d'hydrocarbures aliphatiques gazeux. On indique la variation des rendements des differents produits avec la duree de pyrolyse, l'etat gazeux ou liquide du biphenyle, et la pression de la vapeur. Variant la superficie et la nature des parois, on montre qu'en absence de liquide la pyrolyse se fait en phase adsorbee. La pyrolyse est plus active au contact de parois metalliques que de celles de verres (pyrex ou silice). A partir des resultats experimentaux un mecanisme de

  8. The influence of water hardness and PCBs mixtures on embryonic development and hatching of Prussian carp, Carassius gibelio (Actinopterygii: Cypriniformes: Cyprinidae.

    Directory of Open Access Journals (Sweden)

    Magdalena Katarzyna Socha

    2015-11-01

    After 24 h of incubation there was no significant difference in the percentage of live eggs between groups either in experiment with Aroclor 1254 or Delor 103. In the case of hatching rate tested PCBs mixtures had no effect in both variants of water harness. Delor 103 had no effect on the percentage of deformed larvae of Prussian carp in both hard and soft water. Only the observation of the number of deformed larvae showed higher teratogenic influence of Aroclor 1254 in hard water. Summing up, our results showed that Delor 103 is not harmful to the development of activated Prussian carp eggs in both hard and soft water, but in the case of Aroclor 1254 diluted in hard water increased teratogenic effect was observed.

  9. Effects of Developmental Exposure to Polychlorinated Biphenyls and/or Polybrominated Diphenyl Ethers on Cochlear Function

    OpenAIRE

    Poon, Emily; Powers, Brian E.; McAlonan, Ruth M.; Ferguson, Duncan C.; Schantz, Susan L

    2011-01-01

    Developmental exposure to polychlorinated biphenyls (PCBs) causes hearing loss that may be due to reduced thyroxine during cochlear development. Polybrominated diphenyl ethers (PBDEs) are structurally similar to PCBs and reduce thyroxine. This study utilized an environmental PCB mixture and a commercial PBDE mixture, DE-71, that represents the PBDEs found in humans to assess the potential for additive effects of PCBs and PBDEs on cochlear function. Female Long-Evans rats were dosed with corn ...

  10. Rhizospere Redox Cycling and Implications for Rhizosphere Biotransformation of Selected Polychlorinated Biphenyl (PCB) Congeners

    OpenAIRE

    Meggo, Richard E.; Schnoor, Jerald L.

    2013-01-01

    Theoretically, sequential cycles of dechlorination followed by aerobic bio-oxidation are desirable to achieve complete degradation of a mixture of higher and lower chlorinated PCBs. In this research, soil was artificially contaminated with polychlorinated biphenyls (PCBs) in mixture and as single congeners, aged, and planted with two different plant species. Alternating redox cycles were created in the root zone of plants by flooding and draining the soil. Over 32 weeks, switchgrass (Panicum ...

  11. New technologies for PCB [polychlorinated biphenyl] decontamination

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCB) were mixed with chlorobenzenes to reduce viscosity and provide for both electrical insulation and convective heat transfers. These mixtures were known as askarels, and ca 99.8% of PCBs used in electrical applications are contained in askarel-filled transformers and capacitors. It is estimated that there are ca 180 million gal of PCB-contaminated oil distributed through over 3 million transformers in the USA. Technology used for decontaminating these transformers depends on the concentration of the PCB contamination. At low PCB concentrations of up to ca 2,000 ppM, chemical methods can be used; at higher concentrations, alternative disposal options become more attractive. For chemical treatment, a small mobile unit using quick-reacting reagents has been developed for on-site decontamination. For highly contaminated transformers, retrofilling is very attractive since the owner's liability is minimized at minimum cost. Conventional flush/drain procedures have such drawbacks as the inability to remove oil trapped in windings and the leaching of trapped PCBs back into the uncontaminated retrofill oil over time. A new process has been developed to solve the leaching problem and to decontaminate the drained askarel at room temperature using a catalyst. An alternative disposal strategy involves dismantling the transformer carcass, incinerating non-recyclable materials, and cleaning the metals and wire with solvent. 8 figs

  12. Absolute configurations and CD spectra of axially chiral biphenyls prepared in a facile manner by crystallization-induced configuration transformation.

    Science.gov (United States)

    Wang, Limin; Cheng, Senxiang; Chen, Rongfeng; Chang, Junbiao

    2010-08-01

    Axially chiral biphenyls such as (M,S)-3k have been conveniently obtained by crystallization of their diastereomeric mixtures, which were synthesized from racemic 4,4'-dimethoxy-5,6,5',6'-bis(methylenedioxy)-2-carboxylester-2'-carboxyl-biphenyls 4 and chiral amino alcohols (R)-alaninol, (S)-alaninol, (S)-valinol, and (S)-phenylalaninol. A crystallization-induced configuration transformation of the biphenyls was thus achieved. It was found that amide formation of an (S)-valinol or (S)-phenylalaninol at the 2'-position of the biphenyl usually induced the deposition of crystals with the (M)-configuration from ethanol in yields higher than 50%. The absolute configurations (ACs) of two crystalline biphenyls have been determined by X-ray crystallographic analysis. The ACs of nine biphenyls have been assigned based on their CD spectra. Further, stability investigation of these axially chiral biphenyls revealed that the ACs could revert upon redissolution. The energy barrier to epimerization between (P,R)-3b and (M,R)-3b was measured as DeltaG(#) = 21.45 kcal/mol and the half-life in ethanol at 301 K was 17.1 h. PMID:20623583

  13. 1H NMR metabolomics of earthworm responses to polychlorinated biphenyl (PCB) exposure in soil.

    Science.gov (United States)

    Whitfield Åslund, Melissa L; Simpson, André J; Simpson, Myrna J

    2011-06-01

    (1)H NMR-based metabolomics was used to examine the metabolic profile of D(2)O-buffer extracted tissues of Eisenia fetida earthworms exposed for 2 days to an artificial soil spiked with sub-lethal concentrations of polychlorinated biphenyls (PCBs) (0, 0.5, 1, 5, 10, or 25 mg/kg Aroclor 1254). Univariate statistical analysis of the identified metabolites revealed a significant increase in ATP concentration in earthworms exposed to the highest soil PCB concentration, but detected no significant changes in other metabolites. However, a multivariate approach which considers alterations in multiple metabolites simultaneously, identified a significant linear relationship between earthworm metabolic profiles and PCB concentration (cross-validated PLS-regression with 7 components, R(2)X = 0.99, R(2)Y = 0.77, Q(2)Y = 0.45, P earthworms (r = 0.22, P = 0.54), but were positively correlated in earthworms from the 25 mg/kg treatment (r = 0.87, P = 0.001). Overall, the observed metabolic responses suggest that PCBs disrupted both carbohydrate (energy) metabolism and membrane (osmolytic) function in E. fetida. The ability of (1)H NMR-based metabolomics to detect these responses suggests that this method offers significant potential for direct assessment of sub-lethal PCB toxicity in soil. PMID:21424327

  14. Evaluation of the immunotoxicity of low-level PCB (polychlorinated biphenyl) exposure in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Smialowicz, R.J.; Andrews, J.E.; Riddle, M.M.; Rogers, R.R.; Luebke, R.W.

    1989-01-01

    Weanling male Fischer 344 rats were exposed daily by gastric intubation for up to 15 weeks to the polychlorinated biphenyl (PCB) Aroclor 1254 at 0.1, 1, 10, or 25 mg/kg body weight. At 5, 10 and 15 weeks groups of rats were killed and immune functions were evaluated. The immune parameters examined included the following: body and lymphoid organ weights, mitogen stimulated lymphoproliferative (LP) responses, natural killer (NK) cell activity, mixed lymphocyte reaction (MLR), and cytotoxic T lymphocyte (CTL) response. After 10 and 15 weeks of dosing body weights were reduced in rats receiving 25 mg/kg PCB while thymus weights were decreased in rats receiving 10 and 25 mg/kg. NK cell activity was reduced in rats dosed for 15 weeks at 10 and 25 mg/kg. The LP response to phytohemagglutinin was enhanced in rats dosed for 15 weeks at 25 mg/kg PCB. Exposure of rats to PCB did not affect the MLR or CTL responses. Other groups of rats were exposed to cyclophosphamide (CY) and served as positive controls for the immune assays employed. CY induced alterations in all of the immune parameters measured, indicating that this is a sensitive battery of immune function tests which is capable of detecting immune alterations in the rat.

  15. Comparative study of estrogenic effects of estradiol,nonylphenol,polychlorinated biphenyls,cadmium,zinc and its mixtures on Tanichthys albonubes%雌二醇、壬基酚、多氯联苯、镉和锌及其混合物对唐鱼的雌激素效应比较

    Institute of Scientific and Technical Information of China (English)

    杨丽丽; 张晶; 方展强

    2011-01-01

    以唐鱼卵黄蛋白原(Vtg)为检测指标,利用Native-PAGE电泳、唐鱼Vtg特异性脂蛋白染色和间接酶联免疫吸附(ELISA)技术分别检测了17β-雌二醇(E2)、壬基酚(NP)、多氯联苯(PCBs)、Cd2+、Zn2+及其混合物对唐鱼的雌激素效应.Native-PAGE结果显示,10μg/L、50μg/LE2水体暴露7、14 d均诱导雄性唐鱼体内合成了Vtg,E2对唐鱼的雌激素效应具有时间累积效应,并随浓度升高而增强.而ELISA检测结果则显示0.1、0.5、1.0μg/LE2 7、14d和200、300μg/LNP14d暴露使唐鱼合成了Vtg.结果表明,NP、Cd2+、Zn2+与不同浓度的E2联合雌激素效应不同于单一毒物的雌激素效应,NP与E2表现为协同促进作用.并讨论了环境雌激素的联合作用机制相关问题.%Environmental endocrine disrupting chemicals (EDCs) can affect the normal endocrine system of organism. Its huge threat to the environment and the health of human beings arouses international attention, which has been the hot topic in environmental research. Vitellogenin( Vtg) production in male and juvenile fish can provide a sensitive biomarker of reproductive disruption to indicate and estimate estrogenicity of EDCs. It has been proved that the vitellogenin of Tanichthys albonubes is a perfect biomarker to be used to monitor EDCs in environment. The objective of the present study was to detect the estrogenic responses of estradiol-17 beta(E2) ,nonylphenol(NP),polychlorinated biphenyls(PCBs) ,Cd2+ ,Zn2+and its mixture in T. albonubes. Native-polyacrylamide gel electrophoresis ( Native-PAGE), lipo-staining method, indirect enzyme-linked immunosorbent assay(ELISA) were used to analyze the whole body homogenate from treated male T. albonubes. The results of Native-PAGE showed that after exposure to 10μg/L E2,50 μg/L E2 for 7 days or 14 days, the male T. albonubes could synthesize Vtg. It also showed that the more time, the more vitellogenin and the higher the concentration of E2, the more Vtg. The results

  16. Bioelectrochemical Immunoassay of Polychlorinated Biphenyl

    International Nuclear Information System (INIS)

    A simple, rapid, and highly sensitive bioelectrochemical immunoassay method based on magnetic beads (MBs) and disposable screen-printed electrodes (SPE) has been developed to detect polychlorinated biphenyls (PCBs). The principle of this bioassay is based on a direct competitive enzyme-linked immunosorbent assay using PCB-antibody-coated MBs and horseradish peroxidase (HRP)-labeled PCB (HRP-PCB). A magnetic process platform was used to mix and shake the samples during the immunoreactions and to separate free and unbound reagents after the liquid-phase competitive immunoreactions among PCB-antibody-coated MBs, PCB analyte, and HRP-PCB. After a complete immunoassay, the HRP tracers attached to MBs were transferred to a substrate solution containing o-aminophenol and hydrogen peroxide for electrochemical detection. The different parameters, including the amount of HRP-PCB conjugates, immunoreaction time, and the concentration of substrate that governs the analytical performance of the immunoassay have been studied in detail and optimized. The detection limit of 5 pg mL-1 was obtained under optimum experimental conditions. The performance of this bioelectrochemical immunoassay was successfully evaluated with untreated river water spiked with PCBs, and the results were validated by commercial PCB enzyme-linked immunosorbent assay kit, indicating that this convenient and sensitive technique offers great promise for decentralized environmental application and trace PCBs monitoring

  17. Determination of polychlorinated biphenyls (PCBs) in insulating oil

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, S.; Goda, Y.; Hirobe, M. [Japan EnvironChemicals Ltd., Tokyo (Japan); Tomita, J.; Nishikiori, M.; Nakajima, T. [Tokyo Electric Power Environmental Engineering Co. Inc., Tokyo (Japan); Rubio, F. [Abraxis LLC, Warminster, PA (United States); Takigami, H. [National Inst. for Environmental Studies, Tsukuba (Japan); Sakai, S. [Kyoto Univ., Kyoto (Japan); Ike, M.; Fujita, M. [Osaka Univ., Osaka (Japan)

    2005-07-01

    This paper described a newly developed cocktail polychlorinated biphenyl (PCB) enzyme-linked immunosorbent assay (ELISA) designed as a pretreatment method for determining levels of PCBs in insulating oils. Standard and pretreated PCBs were dissolved in dimethyl sulfoxide (DMSO) and mixed. The diluted mixture was then combined with a horseradish peroxidase conjugate combined with an anti-PCB antibody coupled with magnetic particles. A comparison of the method with standard ELISA processes indicated that the cocktail showed that cross reactivity patterns were improved. Twenty-six insulating oil samples contaminated with PCBs were then analyzed using the method. Values obtained using the cocktail method correlated with gas chromatography (GC) and mass spectroscopy (MS) analyses conducted on the same samples. It was concluded that the cocktail ELISA technique is a reliable and simple analytical method for determining PCBs in insulating oils. 3 refs., 4 tabs., 2 figs.

  18. Application of tritium-labeled complex technical mixture of PCB congeners as radiotracer in ecological investigations

    International Nuclear Information System (INIS)

    The quantitative analysis of PCBs (polychlorinated biphenyls) is enough difficult analytical task. According to IUPAC nomenclature it is described more than 200 possible PCB congeners from which about 150 congeners are present at an environment. At the same time in environment PCBs are present as complex technical mixes of congeners (trade names include Apirolio, Aroclor, Clophen, Fenchlor, Kanechlor, Phenoclor, Pyralene, Pyranol, Pyroclor, Santotherm FR, and Sovol). In routine practice of gas chromatography analysis the quantitative measurement of PCB marker congeners is applied. In the most samples containing PCBs, there are often several dozens of different congeners. For practical reasons, all of them are not always measured, but the most important congeners are used as indicators. In Belgian chicken incident, only seven abundant congeners were usually measured: congeners with IUPAC numbers 28, 52, 101, 118, 138, 153, and 180 (2,4,4 '-TriCB, 2,2 ', 5,5 '-TCB, 2,2 ', 4,5,5 '-PeCB, 2,3 ', 4,4 ', 5-PeCB, 2,2 ', 3,4,4 ', 5 '-HxCB, 2,2 ', 4,4 ', 5,5 '-HxCB, 2,2 ', 3,4,4 ', 5,5 '-HpCB, respectively). The seven congeners are estimated to constitute about one third of all PCBs in the contaminated feed. Such measurement can give the big error in a quantitative estimation of PCBs contents in a sample. As alternative method of quantitative measurement PCBs the radiochemical method with use radioactive labeled PCBs as radiotracer can be used. We had been developed a method of synthesis of labeled by thermally activated tritium a complex technical mixture of PCBs congeners - Sovol. We had been showed a basic opportunity of receiving of uniformly tritium labeled mixture of PCBs congeners without structural failure of mixture. The tritium labeled preparation of complex technical mixture of PCBs congeners (Sovol) has been received. On the basis of received tritium labeled preparation of PCBs (Sovol) we had been developed the following quantitative and qualitative radiochemical

  19. Microbial transformation and degradation of polychlorinated biphenyls

    International Nuclear Information System (INIS)

    This paper reviews the potential of microorganisms to transform polychlorinated biphenyls (PCBs). In anaerobic environments, higher chlorinated biphenyls can undergo reductive dehalogenation. Meta- and para-chlorines in PCB congeners are more susceptible to dechlorination than ortho-chlorines. Anaerobes catalyzing PCB dechlorination have not been isolated in pure culture but there is strong evidence from enrichment cultures that some Dehalococcoides spp. and other microorganisms within the Chloroflexi phylum can grow by linking the oxidation of H2 to the reductive dechlorination of PCBs. Lower chlorinated biphenyls can be co-metabolized aerobically. Some aerobes can also grow by utilizing PCB congeners containing only one or two chlorines as sole carbon/energy source. An example is the growth of Burkholderia cepacia by transformation of 4-chlorobiphenyl to chlorobenzoates. The latter compounds are susceptible to aerobic mineralization. Higher chlorinated biphenyls therefore are potentially fully biodegradable in a sequence of reductive dechlorination followed by aerobic mineralization of the lower chlorinated products. - Higher chlorinated biphenyls are potentially fully biodegradable in a sequence of anaerobic reductive dechlorination followed by aerobic mineralization of the lower chlorinated products

  20. Spatial and seasonal distribution of polychlorinated biphenyls (PCBs) in the vicinity of an iron and steel making plant.

    Science.gov (United States)

    Baek, Song-Yee; Choi, Sung-Deuk; Park, Hyokeun; Kang, Jung-Ho; Chang, Yoon-Seok

    2010-04-15

    Four consecutive passive air samplings (September 2006-July 2007) were conducted at 15 sites around an iron and steel making plant in Pohang, Korea to investigate the spatial and seasonal distributions of polychlorinated biphenyls (PCBs) and ultimately the source-receptor relationships. Annual mean values of Sigma(8)PCBs (IUPAC number 8, 28, 52, 101, 118, 138, 153, 180) were in the range of 15.1-166 pg/m(3) with an average of 53.0 pg/m(3). The spatial distribution of PCBs for each sampling period clearly suggests that the steel complex is a major source of PCBs in this area, and the prevailing winds facilitated the atmospheric transport and dispersion of PCBs from the steel complex to the surrounding areas. Seasonal patterns of PCBs were observed clearly, which were influenced by meteorological conditions; the highest levels of PCBs were observed with the highest average air temperature, and the influence of rainfall (i.e., wet scavenging) was also observed. In addition, PCB 11, a non-Aroclor congener, was detected in high concentrations at all sites, implying that the sources of PCB 11 are both unique and ubiquitous. This study confirms that passive air sampling is a useful tool to obtain seasonal and spatial distributions of time-averaged POPs data at a local scale.

  1. The relation of polychlorinated biphenyls to birth weight and gestational age in the offspring of occupationally exposed mothers

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, P.R.; Stelma, J.M.; Lawrence, C.E. (National Cancer Institute, Bethesda, MD (USA))

    1989-02-01

    The authors studied the relation of polychlorinated biphenyls (PCBs) to birth weight and gestational age among the live offspring of women occupationally exposed to PCBs during the manufacture of capacitors in Upstate New York. Interviews were conducted in 1982 with 200 women who had held jobs with direct exposure and 205 women who had never held a direct-exposure job in order to ascertain information on reproductive history and other factors influencing reproductive outcome. Exposure was assessed as high-homolog PCB (Aroclor 1254), a continuous exposure variable estimated from an independently derived prediction model. After adjustment for variables other than gestational age known to influence birth weight, a significant effect of high-homolog exposure is seen for birth weight. For gestational age, a small but significant decrease is also observed with an increase in estimated exposure. When gestational age is accounted for in addition to other variables related to birth weight, estimated serum PCB is no longer a significant predictor of birth weight. The authors conclude that these data indicate that there is a significant relation between increased estimated serum PCB level and decreased birth weight and gestational age, and that the decrease in birth weight is at least partially related to shortened gestational age. The magnitude of these effects was quite small compared with those of other known determinants of gestational age and birth weight, and the biologic importance of these effects is likely to be negligible except among already low birth weight or short gestation infants.

  2. EQUILIBRATION OF POLYCHLORINATED BIPHENYLS AND TOXAPHENE WITH AIR AND WATER

    Science.gov (United States)

    The vapor pressure and solubility (as subcooled liquids) and Henry's Law constants (HLCs) for the individual chlorobiphenyl compounds (CBC) in Aroclor 1242, 1254, and 1260, as well as the HLCs for toxaphene, have been determined with an equilibrium technique. The results were obt...

  3. 40 CFR 129.105 - Polychlorinated biphenyls (PCBs).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Polychlorinated biphenyls (PCBs). 129... Polychlorinated biphenyls (PCBs). (a) Specialized definitions. (1) PCB Manufacturer means a manufacturer who produces polychlorinated biphenyls. (2) Electrical capacitor manufacturer means a manufacturer who...

  4. 40 CFR 721.5713 - Phenol - biphenyl polymer condensate (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenol - biphenyl polymer condensate... Specific Chemical Substances § 721.5713 Phenol - biphenyl polymer condensate (generic). (a) Chemical... as a phenol - biphenyl polymer condensate (PMN P-00-1220) is subject to reporting under this...

  5. Reproductive abnormalities, teratogenicity, and developmental problems in American kestrels (Falco sparverius) exposed to polychlorinated biphenyls.

    Science.gov (United States)

    Fernie, Kim; Bortolotti, Gary; Smits, Judit

    2003-11-28

    This study found abnormalities in multiple reproductive stages in captive American kestrels (Falco sparverius) when exposed to polychlorinated biphenyls (PCBs) through dietary and in ovo exposure. American kestrels laid eggs with environmentally relevant total PCB levels (34.1 micrograms/g whole egg wet weight) when consuming PCB-spiked (Aroclor 1248:1254:1260) food (5-7 micrograms/g body weight per day) for 100 d only in 1998. In 1999, the same adults laid eggs with estimated total PCBs of 23 micrograms/g. Effects of maternal (only female exposed) and paternal (only male exposed) in ovo PCB exposure were investigated. Maternal F1 eggs contained predicted total PCB concentrations of 0.34 microgram/g. Specific abnormalities occurred more frequently during dietary F0 exposure, particularly aggressive courtship interactions, clutch abandonment, occurrences of cracked eggs, and developmental effects. Multiple developmental effects were more pronounced during than after dietary PCB exposure of adults, and although these effects were limited, nevertheless they occurred in the F1 maternal and F1 paternal pairs. However, the incidence of multiple deformities throughout the breeding season increased dramatically from 1998 (13%) to 1999 (56%) in F0 PCB-exposed pairs. Developmental abnormalities were unlikely to be attributed to the extrinsic factors of disease, genetics, or nutritional (vitamin D3) deficiencies, but rather to adverse changes in parental behavior and intrinsic factors involving altered genetic material and PCB exposure. Readily cleared PCB congeners may induce specific types of behavioral and developmental abnormalities, but persistent congeners and metabolites are likely producing (1) odd laying patterns, (2) odd laying patterns, (2) developmental effects including embryonic underdevelopment and edema, and (3) increased incidences of multiple deformities within a clutch. PMID:14710594

  6. Updated Abraham solvation parameters for polychlorinated biphenyls

    NARCIS (Netherlands)

    Noort, van P.C.M.; Haftka, J.J.H.; Parsons, J.R.

    2010-01-01

    This study shows that the recently published polychlorinated biphenyl (PCB) Abraham solvation parameters predict PCB air-n-hexadecane and n-octanol-water partition coefficients very poorly, especially for highly ortho-chlorinated congeners. Therefore, an updated set of PCB solvation parameters was d

  7. Updated Abraham solvation parameters for polychlorinated biphenyls

    NARCIS (Netherlands)

    P.C.M. van Noort; J.J.H. Haftka; J.R. Parsons

    2010-01-01

    This study shows that the recently published polychlorinated biphenyl (PCB) Abraham solvation parameters predict PCB air−n-hexadecane and n-octanol−water partition coefficients very poorly, especially for highly ortho-chlorinated congeners. Therefore, an updated set of PCB solvation parameters was d

  8. Uptake and Translocation of Lesser-Chlorinated Polychlorinated Biphenyls (PCBs) in Whole Hybrid Poplar Plants after Hydroponic Exposure

    OpenAIRE

    Liu, Jiyan; Schnoor, Jerald L.

    2008-01-01

    Mono-, di-, tri-, and tetra-chlorinated polychlorinated biphenyls (PCBs) are congeners with greater volatility which remain in air, soils and sediments requiring treatment. In this study, the fate of these PCBs was investigated within whole poplar plants (Populus deltoides x nigra, DN34) with application for a treatment system such as a confined disposal facility for dredged material. Whole hybrid poplars were exposed hydroponically to a mixture of five congeners, common in the environment, h...

  9. Formation of Polychlorinated Biphenyls on Secondary Copper Production Fly Ash: Mechanistic Aspects and Correlation to Other Persistent Organic Pollutants

    OpenAIRE

    Xiaoxu Jiang; Guorui Liu; Mei Wang; Minghui Zheng

    2015-01-01

    Emission of unintentionally formed polychlorinated biphenyls (PCBs) from industrial thermal processes is a global issue. Because the production and use of technical PCB mixtures has been banned, industrial thermal processes have become increasingly important sources of PCBs. Among these processes, secondary copper smelting is an important PCB source in China. In the present study, the potential for fly ash-mediated formation of PCBs in the secondary copper industry, and the mechanisms involve...

  10. Occupational exposure to polychlorinated biphenyls (PCBs).

    OpenAIRE

    Wolff, M S

    1985-01-01

    Human occupational exposure to polychlorinated biphenyls (PCBs) with varying chlorine content has been reported by several investigators, using analyses of blood or adipose samples or skin wipes to evaluate levels in the body. The intensity of occupational exposure is related to both duration and intensity of exposure. The qualitative nature of occupational exposure, as well as casual environmental exposure, has been shown to consist of less readily metabolized PCB congeners. The pattern of P...

  11. ADSORPTION OF POLYCHLORINATED BIPHENYLS BY SOILS

    OpenAIRE

    Mihaela Preda; Radu Lăcătuşu; Dumitru Marian Motelică; Nicoleta Vrînceanu; Veronica Tănase

    2010-01-01

    The behavior of polychlorinated biphenyls (PCBs) in soil is determined by several factors including adsorption, mobility and degradation. Adsorption, directly or indirectly, influences the other factors. Adsorption process is generally evaluated by using adsorption isotherms representing the relationship between the quantity of substance adsorbed per unit weight and concentration of the substance in solution at equilibrium. They allow determination of the adsorption constant, which is directl...

  12. Metabolism and metabolites of polychlorinated biphenyls (PCBs)

    OpenAIRE

    Grimm, FA; Hu, D.; Kania-Korwel, I.; Lehmler, HJ; Ludewig, G; Hornbuckle, KC; Duffel, MW; Bergman, A; Robertson, LW

    2015-01-01

    The metabolism of polychlorinated biphenyls (PCBs) is complex and has an impact on toxicity and thereby assessment of PCB risks. A large number of reactive and stable metabolites are formed in the processes of biotransformation in biota in general and in humans in particular. The aim of this document is to provide an overview of PCB metabolism and to identify metabolites of concern and their occurrence. Emphasis is given to mammalian metabolism of PCBs and their hydroxyl, methylsulfonyl, and ...

  13. Differential effects of long-term exposure to Aroclor 1254 on lipid secretion by primary cultures of adult rat hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza-Figueroa, T.; Hernandez, A.; Lopez, L. [Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional (Mexico)

    1992-06-01

    PCBs produce hepatic triglyceride (TG) accumulation (fatty liver) in experimental animals and humans exposed accidentally and occupationally. It has been suggested that this effect could be due to a block in TG secretion. On the other hand, increased levels of plasmatic TG and cholesterol have been described in rats after dietary exposure to Aroclor 1254 (Aro) and other PCBs; hypertriglyceridemia and hypertension have been also described in humans exposed for long periods to low concentrations of PCBs. Since the study of hepatic lipid metabolism and its alteration by toxic chemicals is complicated in the whole animal, short term cultures of adult rat hepatocytes have been used. We have described a system for the long term culture of adult rat hepatocytes which for several weeks maintain differentiated functions, like fatty acid and TG synthesis and their export to the culture medium. In this paper we used this culture system to study the effect of long-term exposure to micromolar concentrations of Aro on the secretion of lipids by cultured hepatocytes. 27 refs., 4 figs., 1 tab.

  14. Separation of Biphenyl Nitrile Compounds by Microemulsion Electrokinetic Chromatography with Mixed Surfactants

    Institute of Scientific and Technical Information of China (English)

    Su Xuan GONG; Tao BO; Lan HUANG; Ke An LI; Hu Wei LIU

    2004-01-01

    A mixture of nine biphenyl nitrile compounds with high hydrophobicity and similar structures was successfully separated by microemulsion electrokinetic chromatography (MEEKC) within 30 min. The buffer system contained 100 mmol/L sodium dodecyl sulfate (SDS), 80 mmol/L sodium cholate (SC), 0.81% heptane, 7.5% n-butanol, 10% acetonitrile and 10 mmol/L borate. The addition of SC, organic modifiers, sample preparation and temperature all showed remarkable effect on the separation. Meanwhile, the MEEKC method was briefly compared with micellar electrokinetic chromatography (MEKC) method.

  15. Metabolic and health consequences of occupational exposure to polychlorinated biphenyls.

    OpenAIRE

    Smith, A B; Schloemer, J; Lowry, L K; Smallwood, A W; Ligo, R N; Tanaka, S.; Stringer, W; Jones, M; Hervin, R; Glueck, C J

    1982-01-01

    In surveys of three groups of workers occupationally exposed to polychlorinated biphenyls (PCBs) serum PCB concentrations were quantitated as lower chlorinated biphenyls (L-PCBs) and higher chlorinated biphenyls (H-PCBs). Serum L-PCB and H-PCB concentrations were many times greater among workers employed in power capacitor manufacturing than exposed areas. Statistically significant positive correlations of symptoms suggestive of mucous membrane and skin irritation, of systemic malaise, and al...

  16. Remediation of PCB [polychlorinated biphenyl] -contaminated soils from scrapyards

    International Nuclear Information System (INIS)

    Much of the recent attention on contamination of the environment by polychlorinated biphenyls (PCB) has focused on liquid PCB spills from electrical equipment. A new, and possibly more serious, source of PCB contamination is the scrap yard, typically located in or near major urban centers, where the local scrap dealer would purchase used transformers or other PCB-containing electrical equipment, recover copper and other metals, and dump the PCB-containing oils on the ground. With the rising value of urban and suburban lands, these scrap yards may be slated for redevelopment, making the cleanup of contaminated soils necessary. The heterogeneous distribution of scrap yard contaminants requires a very detailed site assessment, and the heterogeneous mixture of typical scrap yard contaminants (not only PCB) cannot be treated in a simple fashion. These problems are illustrated for the case of the assessment and cleanup of a scrap yard site in Nova Scotia. A grid block system was used to sample soil at the site, and samples were analyzed for PCB, metals, and hydrocarbons. The most severely contaminated spots were mapped; groundwater patterns were also examined. The remediation process can be divided into 5 phases: physical separation of uncontaminated material; three stages of separation of materials into those having single, several-but-similar, and multicomponent mixed contaminations; and selection of appropriate process technologies. Since there is currently no approved PCB destruction facility in Atlantic Canada, excavated soils containing PCB are stored securely on the site to await approval for some type of incineration process

  17. Toxicity mechanisms and interactions of polychlorinated biphenyls and polybrominated diphenylethers

    Directory of Open Access Journals (Sweden)

    Antonijević Biljana

    2012-01-01

    Full Text Available Polychlorinated biphenyls (PCBs and brominated flame retardants, polybrominated diphenylethers (PBDEs, are widespread environmental contaminants as a result of anthropogenic activities and due to their persistency and resistance to degradation. Both groups of chemicals are placed on the list of persistent organic pollutants (POPs, covered by the Stockholm convention which is aimed to limit or ban the production, use, emission, import and export of POPs in order to protect human health and the environment. Taking into account the structural similarity between PCBs and PBDEs, and the known effects of PCBs, these two groups of chemicals could have similar mechanisms of action. Also, because of real simultaneous exposure to these compounds, an examination of possible interactions is of great importance. Interactions of the compounds from these groups are likely at the system level of hormones, particularly thyroid and reproductive ones. As there are mechanisms of adverse effects of both groups of chemicals on the nervous system, including functional, neurological and behavioral changes, there are influences on neurotransmiters, changes in signal transduction and apoptosis. There are interactions affecting the occurrence of metabolic disorders as well. Data on the toxicity of mixtures of PCBs and PBDEs, as well as interactions of these chemicals would contribute to the processes of risk evaluation and risk characterisation. [Projekat Ministarstva nauke Republike Srbije, br. III 46009

  18. Novel Polyamides Containing Biphenyl-phthalazinone Moieties

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A novel diamine monomer 2H-(4-aminophenyl)-4-[4-(4-aminophenoxy) biphenyl]-phthalazinone 1 containing aza hetero cycle was synthesized and utilized for preparation of new high molecular weight aromatic polyamides with various aromatic dicarboxylic acids with the inherent viscosity of 0.50 ~ 1.62 g/dL. These polyamides had rather high glass transition temperatures of 327~356℃ and their structure was confirmed by IR, 1H NMR and MS. They are readily soluble in polar solvents such as NMP, DMF etc. and easily cast into tough, flexible films.

  19. Establishment of a polychlorinated biphenyl-dechlorinating microbial consortium, specific for doubly flanked chlorines, in a defined, sediment-free medium

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Q.; Sowers, K.R.; May, H.D.

    2000-01-01

    Estuarine sediment from Charleston Harbor, South Carolina, was used as inoculum for the development of an anaerobic enrichment culture that specifically dechlorinates doubly flanked chlorines (i.e., chlorines bound to carbon that are flanked on both sides by other chlorine-carbon bonds) of polychlorinated biphenyls (PCBs). Dechlorination was restricted to the para chlorine in cultures enriched with 10 mM fumarate, 50 ppm (173 {micro}M) 2,3,4,5-tetrachlorobiphenyl, and no sediment. Initially the rate of dechlorination decreased upon the removal of sediment from the medium. However, the dechlorinating activity was sustainable, and following sequential transfer in a defined, sediment-free estuarine medium, the activity increased to levels near that observed with sediment. The culture was nonmethanogenic, and molybdate, ampicillin, chloramphenicol, neomycin, and streptomycin inhibited dechlorination activity; bromethanesulfonate and vancomycin did not. Addition of 17 PCB congeners indicated that the culture specifically removes double flanked chlorines, preferably in the para position, and does not attack ortho chlorines. This is the first microbial consortium shown to para or meta dechlorinate a PCB congener in a defined sediment-free medium. It is the second PCB-dechlorinating enrichment culture to be sustained in the absence of sediment, but its dechlorinating capabilities are entirely different from those of the other sediment-free PCB-dechlorinating culture, an ortho-dechlorinating consortium, and do not match any previously published Aroclor-dechlorinating patterns.

  20. A new biphenyl from Clusia melchiorii and a new tocotrienol from C. obdeltifolia

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Josanaide S.R.; Moreira, Luciana de M.; Cruz, Frederico G. [Bahia Univ., Salvador, BA (Brazil). Inst. de Quimica]. E-mail: fguare@ufba.br; Guedes, Maria L. da S. [Bahia Univ., Salvador, BA (Brazil). Inst. de Biologia

    2006-08-15

    Chromatographic purification of the dichloromethane extract of Clusia melchiorii trunk leading to the isolation of a new biphenyl, 2,2-dimethyl-5-hydroxy-7-phenylchromene, along with the known compounds 2,2-dimethyl-5,10-dihydro-2H-benzo[g]chromene-5,10-dione (xyloidone), betulinic acid, friedelin, friedelinol, euphol, sitostenone, stigmastenone and a mixture of {beta}-sitosterol and stigmasterol. The hexane extract of Clusia obdeltifolia trunk yielded, after chromatographic fractionation, a new {delta}-tocotrienilic alcohol 2Z, 6E, 10E-13-(6-hydroxy- 2,8-dimethyl-3,4-dihydro-2H,2-chromenyl)-2,6,10-trimethyl- 2,6,10-tridecatrien-1-ol, along with 2Z and 2E-{delta}-tocotrienoloic acids, betulinic acid, betulonic acid, betunilic aldehyde, glutinol, friedelin, sitostenone and a mixture of {beta}-sitosterol and stigmasterol. Their structures were determined from spectral data and comparison with data from previously reported compounds. (author)

  1. ADSORPTION OF POLYCHLORINATED BIPHENYLS BY SOILS

    Directory of Open Access Journals (Sweden)

    Mihaela Preda

    2010-01-01

    Full Text Available The behavior of polychlorinated biphenyls (PCBs in soil is determined by several factors including adsorption, mobility and degradation. Adsorption, directly or indirectly, influences the other factors. Adsorption process is generally evaluated by using adsorption isotherms representing the relationship between the quantity of substance adsorbed per unit weight and concentration of the substance in solution at equilibrium. They allow determination of the adsorption constant, which is directly proportional to the adsorption of PCBs in soil. PCBs are very insoluble in water, so they tend to accumulate in the lipids. This is the reason why polychlorinated biphenyls are more strongly adsorbed in soils with higher organic matter content. To obtain the adsorption isotherm were used standard solutions of PCB 101with initial concentrations: 0.05, 0.1, 0.5, 1 and 2 g/ml. The adsorption constants were in order: 3072 ml/g for chernozem, 2943 mg/l for chromic luvisol, 998 mg/l for aluviosol and 1443 mg/l for anthrosol. The values of adsorption constants depend on the organic matter and clay content.

  2. Oxidation of polychlorinated biphenyls by Pseudomonas sp. strain LB400 and Pseudomonas pseudoalcaligenes KF707.

    OpenAIRE

    Gibson, D T; Cruden, D. L.; Haddock, J D; Zylstra, G J; Brand, J M

    1993-01-01

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in the substrate specificity of the biphenyl 2,3-dioxygenases from both organisms.

  3. L-Theanine alleviates the neuropathological changes induced by PCB (Aroclor 1254) via inhibiting upregulation of inflammatory cytokines and oxidative stress in rat brain.

    Science.gov (United States)

    Sumathi, Thangarajan; Asha, Deivasigamani; Nagarajan, Ganesan; Sreenivas, Arivazhagan; Nivedha, Rajendran

    2016-03-01

    The present study is aimed at evaluating the protective role of L-theanine on aroclor 1254-induced oxidative stress in rat brain. Intraperitoneal administration of Aroclor 1254 (2 mg/kg b.wt. for 30 days) caused oxidative stress in rat brain and also caused neurobehavioral changes. Oxidative stress was assessed by determining the levels of lipid peroxide (LPO), protein carbonyl content, and changes in activities of creatine kinase (CK), acetylcholinesterase (AchE), and ATPases in the hippocampus, cerebellum and cerebral cortex of control and experimental rats. Histopathological results showed that PCB caused neuronal loss in all three regions. PCB upregulated the mRNA expressions of inflammatory cytokines. Oral administration of L-theanine (200 mg/kg b.wt.) increased the status of antioxidants, decreased the levels of LPO, nitric oxide (NO) and increased the activities of CK, AchE and ATPases. L-Theanine restored normal architecture of brain regions and downregulated the expression of inflammatory cytokines. In conclusion, L-theanine shows a protective role against PCBs-induced oxidative damage in rat brain.

  4. Sphingobium fuliginis HC3: a novel and robust isolated biphenyl- and polychlorinated biphenyls-degrading bacterium without dead-end intermediates accumulation.

    Directory of Open Access Journals (Sweden)

    Jinxing Hu

    Full Text Available Biphenyl and polychlorinated biphenyls (PCBs are typical environmental pollutants. However, these pollutants are hard to be totally mineralized by environmental microorganisms. One reason for this is the accumulation of dead-end intermediates during biphenyl and PCBs biodegradation, especially benzoate and chlorobenzoates (CBAs. Until now, only a few microorganisms have been reported to have the ability to completely mineralize biphenyl and PCBs. In this research, a novel bacterium HC3, which could degrade biphenyl and PCBs without dead-end intermediates accumulation, was isolated from PCBs-contaminated soil and identified as Sphingobium fuliginis. Benzoate and 3-chlorobenzoate (3-CBA transformed from biphenyl and 3-chlorobiphenyl (3-CB could be rapidly degraded by HC3. This strain has strong degradation ability of biphenyl, lower chlorinated (mono-, di- and tri- PCBs as well as mono-CBAs, and the biphenyl/PCBs catabolic genes of HC3 are cloned on its plasmid. It could degrade 80.7% of 100 mg L -1 biphenyl within 24 h and its biphenyl degradation ability could be enhanced by adding readily available carbon sources such as tryptone and yeast extract. As far as we know, HC3 is the first reported that can degrade biphenyl and 3-CB without accumulation of benzoate and 3-CBA in the genus Sphingobium, which indicates the bacterium has the potential to totally mineralize biphenyl/PCBs and might be a good candidate for restoring biphenyl/PCBs-polluted environments.

  5. Spatial gradients of polychlorinated biphenyls (PCBs) and organochlorine pesticides

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spatial gradients of polychlorinated biphenyls (PCBs) and organochlorine pesticides were examined in the young-of-the-year (YOY) blue多sh collected in the vicinity...

  6. Bioaccumulation dynamics of polychlorinated biphenyls (PCBs) and organochlorine pesticides

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bioaccumulation dynamics of polychlorinated biphenyls (PCBs) and organochlorine pesticides was examined in young-of-the-year bluefish from seven sub-estuaries of...

  7. Sphingobium fuliginis HC3: A Novel and Robust Isolated Biphenyl- and Polychlorinated Biphenyls-Degrading Bacterium without Dead-End Intermediates Accumulation

    OpenAIRE

    Hu, Jinxing; Qian, Mingrong; Zhang, Qian; Cui, Jinglan; Yu, Chunna; Su, Xiaomei; Shen, Chaofeng; Hashmi, Muhammad Z.; Shi, Jiyan

    2015-01-01

    Biphenyl and polychlorinated biphenyls (PCBs) are typical environmental pollutants. However, these pollutants are hard to be totally mineralized by environmental microorganisms. One reason for this is the accumulation of dead-end intermediates during biphenyl and PCBs biodegradation, especially benzoate and chlorobenzoates (CBAs). Until now, only a few microorganisms have been reported to have the ability to completely mineralize biphenyl and PCBs. In this research, a novel bacterium HC3, whi...

  8. NUCLEOTIDE SEQUENCING AND TRANSCRIPTIONAL MAPPING OF THE GENES ENCODING BIPHENYL DIOXYGENASE, A MULTICOM- PONENT POLYCHLORINATED-BIPHENYL-DEGRADING ENZYME IN PSEUDOMONAS STRAIN LB400

    Science.gov (United States)

    The DNA region encoding biphenyl dioxygenase, the first enzyme in the biphenyl-polychlorinated biphenyl degradation pathway of Pseudomonas species strain LB400, was sequenced. Six open reading frames were identified, four of which are homologous to the components of toluene dioxy...

  9. ENANTIOMER SEPARATION OF POLYCHLORINATED BIPHENYL ATROPISOMERS AND POLYCHLORINATED BIPHENYL RETENTION BEHAVIOR ON MODIFIED CYCLODEXTRIN CAPILLARY GAS CHROMATOGRAPHY COLUMNS

    Science.gov (United States)

    Seven commercially-available chiral capillary gas chromatography columns containing modified cyclodextrins were evaluated for their ability to separate enantiomers of the 19 stable chiral polychlorinated biphenyl (PCB) atropisomers, and for their ability to separate these enantio...

  10. Polychlorinated biphenyls alter expression of alpha-synuclein, synaptophysin and parkin in the rat brain

    DEFF Research Database (Denmark)

    Malkiewicz, Katarzyna; Mohammed, Roma; Folkesson, Ronnie;

    2006-01-01

    function and/or are associated with neurodegeneration. Wistar rats were treated orally with repeated doses of Aroclor 1254 and the levels of soluble alpha-synuclein, parkin, synaptophysin and amyloid precursor protein (APP) in the brain were determined by Western blotting. The results showed that Aroclor......-synuclein was accompanied by a transient increase in parkin and synaptophysin levels. Interestingly, in the hypothalamus the levels of alpha-synuclein remained decreased after 21 days post treatment perhaps due to regional differences in the PCBs elimination or perhaps a more specific interaction with the dopaminergic...

  11. Consolidated PCBs [polychlorinated biphenyls] improves waste control

    International Nuclear Information System (INIS)

    Consolidation of polychlorinated biphenyl (PCB) wastes is recommended for improving ownership control of wastes, eliminating PCB storage sites, and increasing cost-effectiveness of waste management. In Ontario, sites receiving the waste must be owned by the waste generator and registered as a PCB site. All PCBs must be removed from a site with no contaminated materials or wastes left behind, which requires a thorough site assessment to identify wastes prior to removal, a sampling and analytical scheme if necessary, and an approved plan for site cleanup. If large volumes of PCB-contaminated oil are involved, it may be cost-effective to put oil from several sites into bulk tanks and thus avoid the need to handle and decontaminate a large number of drums. With low volumes of oil, it may be possible to move the waste to another site where mobile PCB destruction is taking place. It also may be possible to get approval to blend high-level PCB liquids with mineral oil to reduce the PCB concentration to a level where chemical decontamination is allowed. For large volumes of high-level PCB wastes, consolidation will be necessary simply because of the high costs of mobilizing an incinerator and the requirement for public hearings for each incineration project. To make such a project cost-effective, PCB wastes will have to be concentrated from a large geographic area. 1 fig

  12. Accumulation and depletion of polychlorinated biphenyl (PCB) congeners in the housefly (musca domestica, L. )

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, L.G. (Univ. of Illinois, Urbana (United States)); Storr-Hansen, E. (National Environmental Research Inst., Soeborg (Denmark))

    1992-01-01

    Polychlorinated biphenyl (PCB) residues in food chains and in the environment are dynamic complex mixtures and there is considerable interest in the disposition as well as toxicities of individual congeners. The persistence and biological activities of PCBs are intimately associated with microsomal monooxygenases. The house fly, Musca domestica (L.), has long been a standard organism for studies of pesticide toxicology and has an active and well-defined microsomal monooxygenase system. These oxidases in the fly can be induced by PCBs. It was considered of interest to provide data which may indicate whether or not the relatively large and mobile biomass of insects in general may play a role in the global disposition of PCBs. It was also of interest to determine if the house fly could serve as a model for determining the relative accumulation, elimination, and toxicities of individual PCB congeners.

  13. Mixture Density Mercer Kernels

    Data.gov (United States)

    National Aeronautics and Space Administration — We present a method of generating Mercer Kernels from an ensemble of probabilistic mixture models, where each mixture model is generated from a Bayesian mixture...

  14. 75 FR 34076 - Polychlorinated Biphenyls (PCBs); Reassessment of Use Authorizations; Extension of Comment Period...

    Science.gov (United States)

    2010-06-16

    ... AGENCY 40 CFR Part 761 RIN 2070-AJ38 Polychlorinated Biphenyls (PCBs); Reassessment of Use Authorizations..., Hazardous substances, Labeling, Polychlorinated biphenyls (PCBs), Reporting and recordkeeping requirements..., 2010, concerning the reassessment of the use authorizations for PCBs. This document extends the...

  15. Tumour promotion by complex mixtures of polyhalogeneted aromatic hydrocarbons (PHAHs) an the applicability of the toxic equivalency factor (TEF) concept

    NARCIS (Netherlands)

    Plas, van der S.A.

    2000-01-01

    The aim of the project described in this thesis consisted of two main objectives, first, to examine the tumour promotion potential of complex, environmentally relevant mixtures of polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p -dioxins (PCDDs) and polychlorinated dibenzo- p -furans (PC

  16. Estrogenicity of selected biphenyls evaluated using a recombinant yeast assay

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, T.W.; Kraut, D.H.; Sayler, G.S.; Layton, A.C. [Univ. of Tennessee, Knoxville, TN (United States)

    1998-09-01

    The estrogenic activity of biphenyl and 4-hydroxylated derivatives with varied levels of chloro- and/or hydroxyl substitution was measured in a Saccharomyces cerevisiae-based lac-Z ({beta}-galactosidase) reporter assay, {beta}-Galactosidase activity was compared with competitive binding to soluble mouse uterine estrogen receptor protein. The comparison of relative potency for biphenyls hydroxylated on one ring and chlorinated on the other ring (n = 5) revealed excellent correlation between the two systems (r{sup 2} = 0.995). However, estrogenicities of biphenyls hydroxylated and chlorinated on the same ring were not in agreement. Although weak ligand binding was demonstrated for these compounds, {beta}-galactosidase activity was not observed. Rather, these compounds were shown to be cytotoxic to yeast. The results of this study further support the hypothesis that both an unhindered phenolic ring and molecular symmetry are structural features associated with estrogenicity.

  17. Exposure Monitoring and Risk Assessment of Biphenyl in the Workplace

    Directory of Open Access Journals (Sweden)

    Hyeon-Yeong Kim

    2015-05-01

    Full Text Available This study was performed to assess exposure to and the risk caused by biphenyl in the workplace. Biphenyl is widely used as a heat transfer medium and as an emulsifier and polish in industry. Vapor or high levels of dust inhalation and dermal exposure to biphenyl can cause eye inflammation, irritation of respiratory organs, and permanent lesions in the liver and nervous system. In this study, the workplace environment concentrations were assessed as central tendency exposure and reasonable maximum exposure and were shown to be 0.03 and 0.12 mg/m3, respectively. In addition, the carcinogenic risk of biphenyl as determined by risk assessment was 0.14 × 10−4 (central tendency exposure and 0.56 × 10−4 (reasonable maximum exposure, which is below the acceptable risk value of 1.0 × 10−4. Furthermore, the central tendency exposure and reasonable maximum exposure hazard quotients were 0.01 and 0.06 for oral toxicity, 0.05 and 0.23 for inhalation toxicity, and 0.08 and 0.39 for reproduction toxicity, respectively, which are all lower than the acceptable hazard quotient of 1.0. Therefore, exposure to biphenyl was found to be safe in current workplace environments. Because occupational exposure limits are based on socioeconomic assessment, they are generally higher than true values seen in toxicity experiments. Based on the results of exposure monitoring of biphenyl, the current occupational exposure limits in Korea could be reviewed.

  18. 75 FR 4759 - Polychlorinated Biphenyls: Manufacturing (Import) Exemption for Veolia ES Technical Solutions, LLC

    Science.gov (United States)

    2010-01-29

    ... commerce of polychlorinated biphenyls (PCBs). Under TSCA section 3(7), ``manufacture'' is defined to... AGENCY 40 CFR Part 761 RIN 2050-AG42 Polychlorinated Biphenyls: Manufacturing (Import) Exemption for...'s request in the proposed rule, Polychlorinated Biphenyls: Manufacturing (Import) Exemption...

  19. OXIDATION OF POLYCHLORINATED BIPHENYLS BY PSEUDOMONAS SP. STRAIN LB400 AND PSEUDOMONAS PSEUDOALCALIGENES KF707

    Science.gov (United States)

    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in th...

  20. OXIDATION OF BIPHENYL BY A MULTICOMPONENT ENZYME SYSTEM FROM PSEUDOMONAS SP. STRAIN LB400

    Science.gov (United States)

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of bipheny...

  1. Tumour promotion by complex mixtures of polyhalogeneted aromatic hydrocarbons (PHAHs) an the applicability of the toxic equivalency factor (TEF) concept

    OpenAIRE

    Plas, van der, G.

    2000-01-01

    The aim of the project described in this thesis consisted of two main objectives, first, to examine the tumour promotion potential of complex, environmentally relevant mixtures of polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p -dioxins (PCDDs) and polychlorinated dibenzo- p -furans (PCDFs) and secondly, to evaluate the applicability of the Toxic Equivalency Factor (TEF) concept for the tumour promotion potential of complex mixtures of PCBs, PCDDs and PCDFs. In addition, the effe...

  2. POLYCHLORINATED BIPHENYL MIXTURES BUT NOT INDIVIDUAL CONGENERS INHIBIT B LYMPHOCYTE PROLIFERATION. (R826687)

    Science.gov (United States)

    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...

  3. Incidence of thyroid disease following exposure to polybrominated biphenyls and polychlorinated biphenyls, Michigan, 1974-2006.

    Science.gov (United States)

    Yard, Ellen E; Terrell, Metrecia L; Hunt, Danielle Rentz; Cameron, Lorraine L; Small, Chanley M; McGeehin, Michael A; Marcus, Michele

    2011-08-01

    Thyroid hormones, which influence body metabolism and development, could be affected by persistent organic pollutants. We sought to examine the relationship between polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) and thyroid disease. We employed incidence density sampling to perform a nested case control analysis of the Michigan Long-Term PBB Cohort. Cohort members (n=3333) were exposed to PBBs through contaminated cattle feed in 1973-1974 and to PCBs through daily life. Those with detectable serum PBB and PCB concentrations at enrollment were categorized into tertiles of PBB and PCB exposure. Case-patients were cohort members answering "Yes" to "Has a healthcare provider ever told you that you had a thyroid problem?" during follow-up interviews; control-patients were cohort members answering "No". We used odds ratios (OR) with 95% confidence intervals (CI) to compare odds of thyroid disease by PBB and PCB exposure and by various risk factors. Total cumulative thyroid disease incidence after 33 years was 13.9% among women and 2.6% among men. After adjusting for body mass index, we found no statistically significant differences in odds of any type of thyroid disease among women or men with elevated PBB or PCB exposure. Compared to control-patients, women with thyroid disease had increased odds of being overweight/obese (OR=2.82, 95% CI: 1.94-4.11) and developing infertility (OR=1.71, 95% CI: 1.08-2.69), diabetes (OR=1.61, 95% CI: 1.04-2.51), or arthritis (OR=1.71, 95% CI: 1.18-2.50) during follow-up. Additional research should explore potential associations between PBBs/PCBs and thyroid disease among children exposed in utero. PMID:21737118

  4. Danish emission inventory for hexachlorobenzene and polychlorinated biphenyls

    DEFF Research Database (Denmark)

    Nielsen, Ole-Kenneth; Plejdrup, Marlene Schmidt; Winther, Morten;

    This report documents the improved air emission inventories for hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs). The emission inventories now include all sources covered by the EMEP/EEA Guidebook. The completeness and accuracy of the inventories for these pollutants have been signifi...

  5. 77 FR 54818 - Polychlorinated Biphenyls (PCBs): Revisions to Manifesting Regulations

    Science.gov (United States)

    2012-09-06

    ... AGENCY 40 CFR Part 761 RIN 2050-AG71 Polychlorinated Biphenyls (PCBs): Revisions to Manifesting... manifesting requirements for PCBs under TSCA to the manifesting requirements for hazardous waste under RCRA... bring into alignment, as much as possible, the manifesting requirements for PCBs to those of...

  6. FIBER OPTIC FLUOROIMMUNOSENSOR FOR THE DETECTION OF POLYCHLORINATED BIPHENYLS

    Science.gov (United States)

    There currently exists a critical and growing need for cost-effective, real-time, and in situ methods for detection of environmental pollutants such as polychlorinated biphenyls (PCBs). erein reported is a evanescent wave Fluoroimmunosensor for measurement of PCBS. 2,4-5-Trichlor...

  7. Comparison of polychlorinated biphenyl levels across studies of human neurodevelopment

    NARCIS (Netherlands)

    Longnecker, MP; Gladen, BC; Brock, JW; Grandjean, P; Jacobson, JL; Korrick, SA; Rogan, WJ; Weisglas-Kuperus, N; Hertz-Picciotto, [No Value; Ayotte, P; Stewart, P; Winneke, G; Charles, MJ; Jacobson, SW; Dewailly, E; Boersma, ER; Altshul, LM; Heinzow, B; Pagano, JJ; Jensen, AA

    2003-01-01

    Polychlorinated biphenyls (PCBs) are persistent pollutants that are ubiquitous in the food chain, and detectable amounts are in the blood of almost every person in most populations that have been examined. Extensive evidence from animal studies shows that PCBs are neurotoxins, even at low doses. Int

  8. Polychlorinated biphenyls (PCBs) in San Francisco Bay.

    Science.gov (United States)

    Davis, J A; Hetzel, F; Oram, J J; McKee, L J

    2007-09-01

    San Francisco Bay is facing a legacy of polychlorinated biphenyls (PCBs) spread widely across the land surface of the watershed, mixed deep into the sediment of the Bay, and contaminating the Bay food web to a degree that poses health risks to humans and wildlife. In response to this persistent problem, water quality managers are establishing a PCB total maximum daily load (TMDL) and implementation plan to accelerate the recovery of the Bay from decades of PCB contamination. This article provides a review of progress made over the past 15 years in managing PCBs and understanding their sources, pathways, fate, and effects in the Bay, and highlights remaining information needs that should be addressed in the next 10 years. The phaseout of PCBs during the 1970s and the 1979 federal ban on sale and production led to gradual declines from the 1970s to the present. However, 25 years after the ban, PCB concentrations in some Bay sport fish today are still more than ten times higher than the threshold of concern for human health. Without further management action it appears that the general recovery of the Bay from PCB contamination will take many more decades. PCB concentrations in sport fish were, along with mercury, a primary cause of a consumption advisory for the Bay and the consequent classification of the Bay as an impaired water body. Several sources of information indicate that PCB concentrations in the Bay may also be high enough to adversely affect wildlife, including rare and endangered species. The greater than 90% reduction in food web contamination needed to meet the targets for protection of human health would likely also generally eliminate risks to wildlife. PCB contamination in the Bay is primarily associated with industrial areas along the shoreline and in local watersheds. Strong spatial gradients in PCB concentrations persist decades after the release of these chemicals to Bay Area waterways. Through the TMDL process, attention is being more sharply

  9. Optimal mixture experiments

    CERN Document Server

    Sinha, B K; Pal, Manisha; Das, P

    2014-01-01

    The book dwells mainly on the optimality aspects of mixture designs. As mixture models are a special case of regression models, a general discussion on regression designs has been presented, which includes topics like continuous designs, de la Garza phenomenon, Loewner order domination, Equivalence theorems for different optimality criteria and standard optimality results for single variable polynomial regression and multivariate linear and quadratic regression models. This is followed by a review of the available literature on estimation of parameters in mixture models. Based on recent research findings, the volume also introduces optimal mixture designs for estimation of optimum mixing proportions in different mixture models, which include Scheffé’s quadratic model, Darroch-Waller model, log- contrast model, mixture-amount models, random coefficient models and multi-response model.  Robust mixture designs and mixture designs in blocks have been also reviewed. Moreover, some applications of mixture desig...

  10. 汾河表层沉积物PCBs和OCPs含量、来源及生态风险%Polychlorinated biphenyl and organochlorine pesticides in surface sediments of Fenhe River: The concentration,sources and ecological risk.

    Institute of Scientific and Technical Information of China (English)

    郭掌珍; 孟会生; 张渊; 李维宏; 郭青霞

    2013-01-01

    利用G-C-ECD方法测定了汾河太原段30个表层沉积物样品中多氯联苯(PCBs)和有机氯农药(OCPs)的含量,同时对沉积物中PCBs和OCPs的来源和生态风险进行了研究.结果表明,研究区PCBs和OCPs的含量分别为n.d.~50.95μg/kg和2.19 ~25.24μg/kg.Aroclor检出率最高为Aroclor 1260和Aroclor1254,这可能与我国主要生产和使用的PCB有关.OCPs中p,p'-DDE含量占优势,研究区HCH和DDT来源于工业和农业输入.生态风险评价结果表明,γ-HCH、DDT(total),o,p’+p,p’-DDT,p,p’-DDE,七氯环氧化物,PCBs总量可能会对研究区水生生态环境造成潜在影响,但整体风险水平不高.%Concentration of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined with GC-ECD in thirty surface sediment samples collected from Fenhe River in Taiyuan, while the pollution sources and ecological risk were studied. The results indicated that the total concentrations of PCBs and OCPs in sediment ranged from n.d.~50.95ug/kg and 2.19~25.24ug/kg, respectively. For PCBs, Aroclorl260 and Aroclorl254 were predominant isomers, which might be related to PCBs production and use of history in China. For OCPs, p,pf-DDE were predominant congeners. Hexachlorocyclohexane (HCH) and dichlorodiphenytrichloroethanes (DDT) originated from industrial and agricultural usage. Ecological risk assessment of sediment indicated that sediments in Fenhe River were not constituted a serious threat to the ecological system, but y-RCH, totle DDT, o,p'+p,p'-DDT, p,p'-DDE, Heptachlor-exo-epoxide and totle PCBs likely to pose potential biological adverse impact.

  11. Purging mixture for extruder

    OpenAIRE

    Okpala, Chukwubuike

    2015-01-01

    This thesis work focuses on compounding a mechanical purge mixture for extruders. The base resin for making the purge mixture is recycled High Density Polyethylene chosen for its high density and good processing temperature. The additives are mainly clay and sili-con dioxide added as filler and scrubbing materials respectively. The purge mixture was produced by mixing the base resin and additives in percentage ratios into five places la-beled A, B, C, D, and E. the mixtures were extruded and ...

  12. Low temperature asphalt mixtures

    OpenAIRE

    Modrijan, Damjan

    2006-01-01

    This thesis presents the problem of manufacturing and building in the asphalt mixtures produced by the classical hot procedure and the possibility of manufacturing low temperature asphalt mixtures.We will see the main advantages of low temperature asphalt mixtures prepared with bitumen with organic addition Sasobit and compare it to the classical asphalt mixtures. The advantages and disadvantages of that are valued in the practical example in the conclusion.

  13. Liquids and liquid mixtures

    CERN Document Server

    Rowlinson, J S; Baldwin, J E; Buckingham, A D; Danishefsky, S

    2013-01-01

    Liquids and Liquid Mixtures, Third Edition explores the equilibrium properties of liquids and liquid mixtures and relates them to the properties of the constituent molecules using the methods of statistical thermodynamics. Topics covered include the critical state, fluid mixtures at high pressures, and the statistical thermodynamics of fluids and mixtures. This book consists of eight chapters and begins with an overview of the liquid state and the thermodynamic properties of liquids and liquid mixtures, including vapor pressure and heat capacities. The discussion then turns to the thermodynami

  14. Role of inhalation in exposure to polychlorinated biphenyls (PCBs)

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) are a group of aromatic compounds consisting of a biphenyl variously chlorinated. Industrial production of PCBs started in 1929 and stopped in the second half of the '70s in USA and in the late 80's and 90's in Europe. PCBs are ubiquitous pollutants. The way of human exposure to PCBs is a matter of discussion. Scientific data show that the greater exposure occurs through diet. However, other available data suggest a not marginal role of the inhalation exposure. The sources of PCBs to which population are exposed depend on the amount of redistribution of these compounds released in the environment. The aim of this work is to highlight numerous studies proving that the intake of PCBs by inhalation cannot be neglected, in particular in heavily industrialized areas and where the concentration of PCBs in the environmental matrices is particularly high

  15. Sonochemical Degradation of Polychlorinated Biphenyls in Aqueous Solution

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Polychlorinated biphenyl (PCB) is a kind of persistent and dangerous environmental pollutants. This paper presented the research result of sonochemical degradation of 2-chloro- biphenyl (2-CBP), 4-chlorobiphenyl (4-CBP) and 4,4'-dichlorobiphenyl (4,4'-CBP)in water. The ultrasonic degradation kinetics of 2-CBP, 4-CBP and 4,4'-CBP in water were found to be first-order and the degradation rate coefficients are 3.69×10-2, 3.19×10-2 and 2.06×10-2 at 25±1°C for 2-CBP, 4-CBP and 4,4'-CBP respectively. The influence of initial concentrations, reaction temperature on the ultrasonic decomposition of 2-CBP were also investigated.

  16. The Influence of Polychlorinated Biphenyls Contamination on Soil Protein Expression

    OpenAIRE

    Xi Zhang; Feng Li; Tingting Liu; Cheng Peng; Dechao Duan; Chen Xu; Shenhai Zhu; Jiyan Shi

    2013-01-01

    Polychlorinated biphenyls (PCBs) are typical representative of chlorinated organic pollutants. Given the toxicity of PCBs, there is an urgent need to select an appropriate indicator to monitor their biological effects on soil ecosystems. For this purpose, we investigated the impacts of PCBs on soil protein and the potential of using protein as a biological indicator to assess soil contamination due to PCBs. This study demonstrated that soil protein concentration and expression were negatively...

  17. Anaerobic Dehalogenation of Hydroxylated Polychlorinated Biphenyls by Desulfitobacterium dehalogenans

    OpenAIRE

    Wiegel, Juergen; Zhang, Xiaoming; Wu, Qingzhong

    1999-01-01

    Ten years after reports on the existence of anaerobic dehalogenation of polychlorinated biphenyls (PCBs) in sediment slurries, we report here on the rapid reductive dehalogenation of para-hydroxylated PCBs (HO-PCBs), the excreted main metabolites of PCB in mammals, which can exhibit estrogenic and antiestrogenic activities in humans. The anaerobic bacterium Desulfitobacterium dehalogenans completely dehalogenates all flanking chlorines (chlorines in ortho position to the para-hydroxyl group) ...

  18. Toxicity mechanisms and interactions of polychlorinated biphenyls and polybrominated diphenylethers

    OpenAIRE

    Antonijević Biljana; Milovanović Vesna; Ćurčić Marijana; Janković Saša; Jaćević Vesna; Vučinić Slavica

    2012-01-01

    Polychlorinated biphenyls (PCBs) and brominated flame retardants, polybrominated diphenylethers (PBDEs), are widespread environmental contaminants as a result of anthropogenic activities and due to their persistency and resistance to degradation. Both groups of chemicals are placed on the list of persistent organic pollutants (POPs), covered by the Stockholm convention which is aimed to limit or ban the production, use, emission, import and export of POPs i...

  19. Analysis of polychlorinated biphenyls (PCBs) in human serum.

    OpenAIRE

    Luotamo, M; Järvisalo, J; Aitio, A

    1985-01-01

    Polychlorinated biphenyls (PCBs) are widely dispersed in the environment. Occupational exposure to PCBs takes place, e.g., in manufacture and repair of capacitors and transformers. A special type of exposure of workers to PCBs may occur in connection with accidents where capacitors or transformers containing PCBs products are damaged, as in the case of a fire or electric arcing. The quantitation of PCBs poses several problems: There are 209 different homologs and isomers of PCBs. The isomers ...

  20. Polychlorinated Biphenyl (PCB) carcinogenicity with special emphasis on airborne PCBs

    OpenAIRE

    Robertson, Larry W.; Ludewig, Gabriele

    2011-01-01

    Polychlorinated biphenyls (PCBs) are industrial chemicals used in various applications requiring chemical stabilityand have now become widely dispersed. Their characteristics of persistence, low water/higher lipid solubility, contribute to their ability to bioconcentrate and bioaccumulate. Traditionally PCBs have been regulated as food contaminants and the general population is primarily exposed by that route. PCBs in foodstuffs are generally higher chlorinated, resistant to metabolic breakdo...

  1. Binding of polychlorinated biphenyls to the aryl hydrocarbon receptor.

    OpenAIRE

    Kafafi, S A; Afeefy, H Y; A. H. Ali; Said, H K; Kafafi, A G

    1993-01-01

    A new thermodynamic model for calculating the dissociation constants of complexes formed between the aryl hydrocarbon receptor (AhR) and polychlorinated biphenyls (PCBs) is reported. The free energies of binding of PCBs to AhR are controlled by their lipophilicities, electron affinities, and entropies. The corresponding physicochemical properties of polychlorinated dibenzo-p-dioxins and dibenzofurans also control their interactions with AhR. We present evidence supporting the hypothesis that ...

  2. Gas chromatographic separation of methoxylated polychlorinated biphenyl atropisomers

    OpenAIRE

    Kania-Korwel, Izabela; Vyas, Sandhya M.; Song, Yang; Lehmler, Hans-Joachim

    2008-01-01

    Several polychlorinated biphenyls (PCBs) and their hydroxylated metabolites display axial chirality. Here we describe an enantioselective, gas chromatographic separation of methylated derivatives of hydroxylated (OH-)PCB atropisomers (MeO-PCB) using a chemically bonded β-cyclodextrin column (Chirasil-Dex). The atropisomers of several MeO-PCBs could be separated on this column with resolutions ranging from 0.42–0.87 under isothermal or temperature-programmed conditions. In addition, the enanti...

  3. Polychlorinated Biphenyls Water Pollution along the River Nile, Egypt

    OpenAIRE

    Ayman Mohamed Megahed; Hesham Dahshan; Abd-El-Kader, Mahdy A.; Amr Mohamed Mohamed Abd-Elall; Mariam Hassan Elbana; Ehab Nabawy; Mahmoud, Hend A.

    2015-01-01

    Ten polychlorinated biphenyl (PCB) congeners were determined in water samples collected along the River Nile using gas chromatography-electron capture detector (GC-ECD). PCB concentrations ranged from 14 to 20 μg/L, which were higher than those reported in previous studies, indicating serious PCB pollution in the River Nile. PCB congener profiles varied depending on the sampling sties. PCB-138 was the predominant congener accounting for more than 18% of total PCBs. The composition of PCB cong...

  4. Polychlorinated Biphenyl Presence in the Columbia River Corridor

    Energy Technology Data Exchange (ETDEWEB)

    R. M. Hermann

    2007-09-06

    The U. S. Department of Energy (DOE) is required by Comprehensive Environmental Response, Compensation, and Liability Act of 1980 regulations to develop a conceptual understanding of potential contaminant releases from the Hanford Site based on an evaluation of existing data and known historical practices. Polychlorinated biphenyls (PCBs) are one environmental contaminant potentially released through leaks, spills, or disposal. This document presents a summary of selected relevant existing information, including environmental studies and Hanford Site analytical data.

  5. Reactivity of polychlorinated biphenyls in nucleophilic and electrophilic substitutions

    Energy Technology Data Exchange (ETDEWEB)

    Gorbunova, Tatyana I., E-mail: gorbunova@ios.uran.ru [I. Ya. Postovskii Institute of Organic Synthesis, Ural Branch, Russian Academy of Sciences, Kovalevskoy St., 22, Ekaterinburg 620990 (Russian Federation); Subbotina, Julia O. [Ural Federal University named after the first President of Russia B.N. Yeltsin, Mira St., 19, Ekaterinburg 620002 (Russian Federation); Saloutin, Viktor I.; Chupakhin, Oleg N. [I. Ya. Postovskii Institute of Organic Synthesis, Ural Branch, Russian Academy of Sciences, Kovalevskoy St., 22, Ekaterinburg 620990 (Russian Federation)

    2014-08-15

    Graphical abstract: - Highlights: • Quantum chemical calculations were carried out for PCBs congeners. • Calculated descriptors were used to explain the PCBs reactivity in S{sub N} and S{sub E} substitutions. • Obtained data were used to estimate the PCBs reactivity in the S{sub N} reactions. • Calculated descriptors were insufficient to explain the PCBs reactivity in the S{sub E} reactions. • New neutralization methods of the large-capacity PCBs were discussed. - Abstract: To explain the chemical reactivity of polychlorinated biphenyls in nucleophilic (S{sub N}) and electrophilic (S{sub E}) substitutions, quantum chemical calculations were carried out at the B3LYP/6-31G(d) level of the Density Functional Theory in gas phase. Carbon atomic charges in biphenyl structure were calculated by the Atoms-in-Molecules method. Chemical hardness and global electrophilicity index parameters were determined for congeners. A comparison of calculated descriptors and experimental data for congener reactivity in the S{sub N} and S{sub E} reactions was made. It is shown that interactions in the S{sub N} mechanism are reactions of the hard acid–hard base type, these are the most effective in case of highly chlorinated substrates. To explain the congener reactivity in the S{sub E} reactions, correct descriptors were not established. The obtained results can be used to carry out chemical transformations of the polychlorinated biphenyls in order to prepare them for microbiological destruction or preservation.

  6. Polychlorinated Biphenyls Induce Oxidative DNA Adducts in Female Sprague-Dawley Rats.

    Science.gov (United States)

    Mutlu, Esra; Gao, Lina; Collins, Leonard B; Walker, Nigel J; Hartwell, Hadley J; Olson, James R; Sun, Wei; Gold, Avram; Ball, Louise M; Swenberg, James A

    2016-08-15

    Polychlorinated biphenyls (PCBs) are organic chemicals that were traditionally produced and widely used in industry as mixtures and are presently formed as byproducts of pigment and dye manufacturing. They are known to persist and bioaccumulate in the environment. Some have been shown to induce liver cancer in rodents. Although the mechanism of the toxicity of PCBs is unknown, it has been shown that they increase oxidative stress, including lipid peroxidation. We hypothesized that oxidative stress-induced DNA damage could be a contributor for PCB carcinogenesis and analyzed several DNA adducts in female Sprague-Dawley rats exposed to 3,3',4,4',5-pentachlorobiphenyl (PCB 126), 2,2',4,4',5,5'-hexachlorobiphenyl (PCB 153), and a binary mixture (PCB 126 + 153) for 14, 31, and 53 wks. Eight adducts were measured to profile oxidative DNA lesions, including 8-oxo-deoxyguanosine (8-oxo-dG), 1,N(6)-ethenodeoxyadenosine (1,N(6)-εdA), N(2),3-ethenoguanine (N(2),3-εG), 1,N(2)-ethenodeoxyguanosine (1,N(2)-εdG), as well as malondialdehyde (M1dG), acrolein (AcrdG), crotonaldehyde (CrdG), and 4-hydroxynonenal-derived dG adducts (HNEdG) by LC-MS/MS analysis. Statistically significant increases were observed for 8-oxo-dG and 1,N(6)-εdA concentrations in hepatic DNA of female rats exposed to the binary mixture (1000 ng/kg/day + 1000 μg/kg/day) but not in rats exposed to PCB 126 (1000 ng/kg/day) or PCB 153 (1000 μg/kg/day) for 14 and 31 wks. However, exposure to PCB 126 (1000 ng/kg/day) for 53 wks significantly increased 8-oxo-dG, 1,N(6)-εdA, AcrdG, and M1dG. Exposure to PCB 153 (1000 μg/kg/day) for 53 wks increased 8-oxo-dG, and 1,N(6)-εdA. Exposure to the binary mixture for 53 wks increased 8-oxo-dG, 1,N(6)-εdA, AcrdG, 1,N(2)-εdG, and N(2),3-εG significantly above control groups. Increased hepatic oxidative DNA adducts following exposure to PCB 126, PCB 153, or the binary mixture shows that an increase in DNA damage may play an important role in hepatic toxicity and

  7. Role of rhizosphere microorganisms in phytoremediation of biphenyl in a contaminated groundwater plume

    International Nuclear Information System (INIS)

    This presentation discussed a pump and treat technology used in combination with a phytoremediation technology to remediate a biphenyl contaminated groundwater plume. Biphenyl is used in industrial applications as fungicide and heat transfer agent. It is highly toxic, has poor water solubility and sorbs strongly to soils. Costs for the project were estimated at $860,000 over a period of 20 years, while it was estimated that the addition of phytoremediation would cost only $125,000 over a period of 20 years. The phytoremediation containment area was added to the site which was comprised of a pump and treat system and landfill lagoons. In situ biodegradation of biphenyl was evaluated using microorganisms in poplar and willow rhizospheres. Basal salts were used as a culture medium. Methods to enhance biphenyl degradation were also investigated. Aerobic growth on biphenyl at temperatures of 8 degrees C were measured, and microbial populations were identified. The consortium with the highest biphenyl degradation was then analyzed. Major members were identified as Burkholderia xenovorans LB400 and a strain of Burkholderia xenovorans. Nitrate reduction, sulphate reduction, and methanogens were measured. Enrichment of anaerobic biphenyl degraders. Anaerobic biphenyl degradation was measured after 90 days. Details of anaerobic mineralization experiments were also provided. It was concluded that anaerobic biphenyl degradation was enhanced by TEA and fertilizer addition, as well as by poplar root exudate. tabs., figs

  8. Synthesis, structural, spectroscopic and thermal characteristics of disubstituted biphenyl derivative: Biphenyl-4,4‧-diacetic acid

    Science.gov (United States)

    Sienkiewicz-Gromiuk, Justyna; Głuchowska, Halina; Tarasiuk, Bogdan; Mazur, Liliana; Rzączyńska, Zofia

    2014-07-01

    A novel 4,4‧-disubstituted biphenyl derivative featuring two acetic acid side arms symmetrically attached to a biphenyl system, that is biphenyl-4,4‧-diacetic acid (H2bpda), has been successfully synthesized by means of the three-stage organic strategy. The synthesis product was characterized by elemental analysis, various spectroscopic techniques including FT-IR, Raman, 1H and 13C NMR as well as thermogravimetric and TG-FT-IR coupled measurements. The phase purity of material was verified on the basis of the X-ray powder diffraction. The studied compound crystallizes in the monoclinic P21/c space group with half of the molecule in the asymmetric unit. Structural studies indicate intermolecular Osbnd H⋯O hydrogen bonding between the carboxylic groups of the adjacent molecules of H2bpda. The occurrence of intermolecularly associated carboxylic groups can also be clearly seen in the vibrational spectra of the acid. On thermal analysis both in air and nitrogen an anhydrous compound demonstrates considerable thermal stability.

  9. Absorption and tissue distribution of radioactivity in mussels (Mytilus Galloprovincialis) exposed to low concentrations of 14C-polychlorinated biphenyl

    International Nuclear Information System (INIS)

    Mussels (Mytilus galloprovincialis) were exposed for 144 h to an isomeric 14C polychlorinated biphenyl (PCB) mixture at an initial concentration of 4.6 μg l-1. Animals were sampled after 6, 12, 24, 72 and 144 h of exposure for sex differences in PCB tissue distribution. PCB was readily absorbed within 12 h and then slowly eliminated from the body with a biological half-time of 209 h. No sexual differences were observed except with mussels sampled at 12 h, where 14C activity was significantly higher (P14C activity measured in gills appeared to be related to the PCB water concentration. 14 refs.; 3 figs.; 1 table

  10. Combined effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin and polychlorinated biphenyls congeners in rats

    Energy Technology Data Exchange (ETDEWEB)

    Chu, I. [Environmental Science Bureau, Ottawa (Canada); Valli, V.E. [Coll. of Veterinary Medicine, Urbana (United States)

    2004-09-15

    There has been considerable interest in conducting toxicity studies on mixtures since this approach represents realistic human exposure and would provide a better model to predict the health impacts of environmental chemicals. However, risk assessment of the chemicals is largely based on the toxicity data of individual compounds by assuming simple additive effects of these compounds. This practice has been accepted by regulatory agencies provided that the concentrations of chemicals are extremely low, and there are no interactions. The existence of interactions among the chemicals co-administered to test animals may under or over estimate the effects of a mixture if the simple additive rule is applied. Previously, we demonstrated an antagonistic effect in rats when tetrachlorodibenzo-p-dioxin (TCDD) was co-administered with polychlorinated biphenyls congeners (PCBs). The hepatic microsomal EROD, MROD and UDPGT activities of TCDD were decreased when co-administered with PCB congeners. To further explore the combined effects of these pollutants, we examined and report results on tissue residue levels of TCDD and histopathological changes in target organs of rats exposed to TCDD, PCBs and mixtures of both.

  11. Determination of polychlorinated biphenyls (PCBs) in insulating oil by cocktail PCB ELISA

    Energy Technology Data Exchange (ETDEWEB)

    Goda, Y.; Hirobe, M.; Fujimoto, S. [Japan EnviroChemicals Ltd., Tokyo (Japan); Tomita, J.; Nishikiori, M.; Nakajima, T. [Tokyo Electric Power Environmental Engineering Co. Inc., Tokyo (Japan); Rubio, F. [Abraxis LLC, Warminster, PA (United States); Takigami, H. [National Inst. for Environmental Studies, Tsukuba (Japan); Sakai, S. [Kyoto Univ., Kyoto (Japan). Environment Preservation Centre; Ike, M.; Fujita, M. [Osaka Univ., Osaka (Japan). Graduate School of Engineering

    2005-07-01

    This paper described a novel cocktail polychlorinated biphenyl (PCB) enzyme-linked immunosorbent assay (ELISA) designed as a simple pretreatment method for the determination of PCBs in insulating oils. Oil samples were treated with hexane and dimethyl sufloxide (DMSO) and mixed. Hexane layers were then removed, and freshly prepared hexane was added. The DMSO layer was then diluted with an aqueous solution and extracted with hexane. After being dehydrated, the hexane layer was sulfonated with a sulfuric reagent and washed. Standard or pretreated PCBs were then dissolved and diluted in 100 per cent DMSO and added to distilled water prior to the ELISA assay. A horseradish peroxidase conjugate and an anti-PCB antibody coupled with magnetic particles were added for the assay. A magnetic rack was used to separate the reaction mixture. A colouring reagent was then added. A total of 26 insulating oils contaminated with PCBs were determined using the new cocktail method and compared with data obtained from traditional gas chromatograph electron capture detector (GC-ECD) data. Results showed that the values of both the cocktail and general PCB ELISA were well correlated with the CG-ECD data. It was concluded that combining cocktail PCB ELISA with the developed pretreatment method provided accurate results. 3 refs., 4 tabs., 2 figs.

  12. Polychlorinated biphenyls in coastal tropical ecosystems: Distribution, fate and risk assessment

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) though banned still find use in most developing countries including Ghana. PCB congener residues in sediments in the coastal regions of Ghana were determined. Sediment samples (n=80) were collected between June 2008 and March 2009, extracted by the continuous soxhlet extraction using (1:1) hexane-acetone mixture for 24 h and analyzed with a CP 3800 gas chromatogram equipped with 65Ni electron capture detector (GC–ECD) and a mixed PCBs standard of the ICES 7 as marker, after clean-up. Validation of the efficiency and precision of the extraction and analytical methods were done by extracting samples spiked with 2 ppm ICES PCB standard and a certified reference material 1941b for marine sediments from NIST, USA, and analyzed alongside the samples. Total PCBs detected in sediments during the dry and wet seasons were, respectively, 127 and 112 μg/kg dry weight (dw), with a mean concentration of 120 μg/kg (dw). The composition of PCB homologues in the sediments were dominated by tri-, penta- and tetra-PCBs. There was no correlation between organic carbon (OC) of the sediments and total PCBs content. Risk assessments conducted on the levels indicated that PCB levels in sediments along the coastal region of Ghana poses no significant health risk to humans.

  13. Polychlorinated biphenyl (PCB) induction of CYP3A4 enzyme activity in healthy Faroese adults

    DEFF Research Database (Denmark)

    Petersen, Maria Skaalum; Halling, Jónrit; Damkier, Per;

    2007-01-01

    The CYP3A4 enzyme is, along with other cytochrome P450 enzymes, involved in the metabolism of environmental pollutants and is highly inducible by these substances. A commercial polychlorinated biphenyl (PCB) mixture, 1,1,1,-trichloro-2-(o-chlorophenyl), 2-(p'-chlorophenyl)ethane (o,p'-DDT) and 1......,1,-dichloro-2,2-bis (p-chlorophenyl)ethene (p,p'-DDE) are known to induce CYP3A4 activity through activation of nuclear receptors, such as the pregnane X receptor. However, this induction of CYP3A4 has not yet been investigated in humans. Thus, the aim of the study was to determine the variability of the CYP3......A4 phenotype in regard to increased concentrations of PCBs and other persistent organohalogen pollutants (POPs) in healthy Faroese adults. In 310 randomly selected Faroese residents aged 18-60 years, the CYP3A4 activity was determined based on the urinary 6beta-hydroxycortisol/cortisol (6beta...

  14. Label-free impedimetric immunoassay for trace levels of polychlorinated biphenyls in insulating oil.

    Science.gov (United States)

    Date, Yasumoto; Aota, Arata; Sasaki, Kazuhiro; Namiki, Yukie; Matsumoto, Norio; Watanabe, Yoshitomo; Ohmura, Naoya; Matsue, Tomokazu

    2014-03-18

    A rapid, ultrasensitive, and practical label-free impedimetric immunoassay for measuring trace levels of total polychlorinated biphenyls (PCBs) in insulating oil was developed. First, we developed a novel monoclonal antibody (RU6F9) for PCBs by using a designed immunogen and characterized its binding affinity for a commercial mixtures of PCBs and its main congeners. A micro comblike gold electrode was fabricated, and the antibody was covalently immobilized on the electrode through a self-assembled monolayer formed by dithiobis-N-succinimidyl propionate. The antigen-binding event on the surface of the functionalized electrode was determined as the change in charge transfer resistance by using electrochemical impedance spectroscopy. The resulting impedimetric immunoassay in aqueous solution achieved a wide determination range (0.01-10 μg/L) and a low detection limit (LOD) of 0.001 μg/L, which was 100-fold more sensitive than a conventional flow-based immunoassay for PCBs. By combining the impedimetric immunoassay with a cleanup procedure for insulating oil utilizing a multilayer cleanup column followed by DMSO partitioning, an LOD of 0.052 mg/kg-oil was achieved, which satisfied the Japanese regulation criterion of 0.5 mg/kg-oil. Finally, the immunoassay was employed to determine total PCB levels in actual used insulating oils (n = 33) sampled from a used transformer containing trace levels of PCBs, and the results agreed well with the Japanese official method (HRGC/HRMS).

  15. Iterative Mixture Component Pruning Algorithm for Gaussian Mixture PHD Filter

    OpenAIRE

    Xiaoxi Yan

    2014-01-01

    As far as the increasing number of mixture components in the Gaussian mixture PHD filter is concerned, an iterative mixture component pruning algorithm is proposed. The pruning algorithm is based on maximizing the posterior probability density of the mixture weights. The entropy distribution of the mixture weights is adopted as the prior distribution of mixture component parameters. The iterative update formulations of the mixture weights are derived by Lagrange multiplier and Lambert W funct...

  16. Biodegradation of biphenyl and 2-chlorobiphenyl by a Pseudomonas sp. KM-04 isolated from PCBs-contaminated coal mine soil.

    Science.gov (United States)

    Nam, In-Hyun; Chon, Chul-Min; Jung, Ka-Young; Kim, Jae-Gon

    2014-07-01

    The biphenyl-degrading strain, Pseudomonas sp. KM-04, was isolated from polychlorinated biphenyls-contaminated soil sample obtained from the vicinity of a former coal mine. We herein report that strain KM-04 can use biphenyl as a sole carbon source, and resting cells convert biphenyl to its corresponding metabolic intermediates. Incubation of KM-04 with autoclaved mining-contaminated soil for 10 days in a slurry system reduced the levels of biphenyl and 2-chlorobiphenyl by 98.5 % and 82.3 %, respectively. Furthermore, treatment of a mine-soil microcosm with strain KM-04 for 15 days in a composting system under laboratory conditions reduced the levels of biphenyl and 2-chlorobiphenyl by 87.1 % and 68.7 %, respectively. These results suggest that KM-04 is a potential candidate for the biological removal of biphenyl and its chlorinated derivatives from polychlorinated biphenyl-contaminated mining areas.

  17. Fluorescent biphenyl derivatives of phenylalanine suitable for protein modification.

    Science.gov (United States)

    Chen, Shengxi; Fahmi, Nour Eddine; Bhattacharya, Chandrabali; Wang, Lin; Jin, Yuguang; Benkovic, Stephen J; Hecht, Sidney M

    2013-11-26

    In a recent study, we demonstrated that structurally compact fluorophores incorporated into the side chains of amino acids could be introduced into dihydrofolate reductase from Escherichia coli (ecDHFR) with minimal disruption of protein structure or function, even when the site of incorporation was within a folded region of the protein. The modified proteins could be employed for FRET measurements, providing sensitive monitors of changes in protein conformation. The very favorable results achieved in that study encouraged us to prepare additional fluorescent amino acids of potential utility for studying protein dynamics. Presently, we describe the synthesis and photophysical characterization of four positional isomers of biphenyl-phenylalanine, all of which were found to exhibit potentially useful fluorescent properties. All four phenylalanine derivatives were used to activate suppressor tRNA transcripts and incorporated into multiple positions of ecDHFR. All phenylalanine derivatives were incorporated with good efficiency into position 16 of ecDHFR and afforded modified proteins that consumed NADPH at rates up to about twice the rate measured for wild type. This phenomenon has been noted on a number of occasions previously and shown to be due to an increase in the off-rate of tetrahydrofolate from the enzyme, altering a step that is normally rate limiting. When introduced into sterically accessible position 49, the four phenylalanine derivatives afforded DHFRs having catalytic function comparable to wild type. The four phenylalanine derivatives were also introduced into position 115 of ecDHFR, which is known to be a folded region of the protein less tolerant of structural alteration. As anticipated, significant differences were noted in the catalytic efficiencies of the derived proteins. The ability of two of the sizable biphenyl-phenylalanine derivatives to be accommodated at position 115 with minimal perturbation of DHFR function is attributed to rotational

  18. Polychlorinated biphenyl exposure and effects in transformer repair workers.

    OpenAIRE

    Emmett, E A

    1985-01-01

    Fifty-five present and past transformer repair workers exposed to polychlorinated biphenyls (PCBs) and 56 unexposed comparison workers were evaluated in a clinical-epidemiologic study. The groups were similar in most demographic variables. Adipose tissue lipid and serum PCBs concentrations were higher in current exposed workers (geometric means adipose 2.1 ppm, serum 12.2 ppb). Concentrations in comparison (0.6 ppm and 4.6 ppb) and previously exposed (0.83 ppm and 5.9 ppb) workers were lower....

  19. Prediction of the Aqueous Solubilities of Polychlorinated Biphenyls

    Institute of Scientific and Technical Information of China (English)

    Shu Shen LIU; Shi Hai CUI; Lian Sheng WANG

    2004-01-01

    Using the molecular electronegativity distance vector descriptors derived directly from the molecular topological structures, the aqueous solubilities of polychlorinated biphenyls(PCBs)were predicted. A three-variable regression equation with correlation coefficient of 0.9739 and the root mean square errors of 0.26 was developed. The descriptors included in the equation represent three interactions between three pairs of atomic types,I.e.,atom-C=and>C=,-C=and-Cl,and-Cland-Cl.It has been proved that the aqueous solubilities of 137 PCB congeners can be accurately predicted as long as there are more than 65 calibration compounds.

  20. Degradation of polychlorinated biphenyls (PCBs) using palladized iron

    International Nuclear Information System (INIS)

    Contamination from polychlorinated biphenyls (PCBs) is a persistent problem within the Department of Energy complex, as well as in numerous industrial sites around the US. To date, commercially available technologies for destroying these highly stable compounds involve degradation at elevated temperatures either through incineration or base-catalyzed dehalogenation at 300 degrees C. Since the heating required with these processes substantially increases the costs for treatment of PCB-contaminated wastes, there is a need for finding an alternative approach where PCB can be degraded at ambient temperatures. This report describes the degradation of PCB's utilizing the bimetallic substrate of iron/palladium

  1. Plasma polychlorinated biphenyls in residents of 91 PCB-contaminated and 108 non-contaminated dwellings

    DEFF Research Database (Denmark)

    Meyer, Harald William; Frederiksen, Marie; Göen, Thomas;

    2013-01-01

    In the1950s-1970s polychlorinated biphenyls (PCBs) were used in several countries as plasticizers in elastic sealants in buildings.......In the1950s-1970s polychlorinated biphenyls (PCBs) were used in several countries as plasticizers in elastic sealants in buildings....

  2. Changes in egg composition of American kestrels exposed to dietary polychlorinated biphenyls.

    Science.gov (United States)

    Fernie, K J; Bortolotti, G R; Smits, J E; Wilson, J; Drouillard, K G; Bird, D M

    2000-06-01

    Changes in the quality of eggs of birds exposed to polychlorinated biphenyls (PCBs) have been described, but have never been directly attributed to PCBs. Polychlorinated biphenyl residues in eggs have been associated with reduced reproductive success and embryonic deformities in wild birds. Egg size and composition, specifically the amount of albumen, yolk, and water in an egg, also influence the growth and viability of embryos and hatchlings, and consequently the reproductive success of birds. To deter mine whether PCB exposure of adult birds affected the size and composition of their eggs, 25 pairs of captive American kestrels (Falco sparverius) were fed a mixture of PCB-spiked (1248:1254:1260) food to give an approximate exposure of 7 mg/kg body weight/d, beginning 1 mo prior to pairing, and continuing throughout the courtship, egg-laying, and incubation periods. This dietary level in the adult female kestrels resulted in mean total PCB residues in the eggs of 34.1 microg/g wet weight (geometric mean), which is environmentally relevant. PCB residues in eggs increased with the time of female exposure to the contaminated diet and laying date. Variation in egg size within PCB clutches was significantly greater than within control clutches, although absolute egg mass and volume did not differ markedly by treatment. Only infertile eggs and only one egg per clutch were used for egg composition analysis. Yolks in the PCB-contaminated eggs were heavier, with less wet and dry albumen relative to control eggs. Water content and eggshell thickness were not significantly affected by PCB exposure. These results suggest that eggs from the PCB treatment have relatively more lipid and less protein available for embryonic development. Changes in egg composition were not associated with egg size, lay date, ambient temperature, humidity, or precipitation, which are factors known to affect these variables in bird eggs. The PCB-induced changes in egg composition described here

  3. Isolation and characteristics of a novel biphenyl-degrading bacterial strain, Dyella ginsengisoli LA-4

    Institute of Scientific and Technical Information of China (English)

    LI Ang; QU Yuanyuan; ZHOU Jiti; GOU Min

    2009-01-01

    A novel biphenyl-degrading bacterial strain LA-4 was isolated from activated sludge. It was identified as Dyella ginsengisoli according to phylogenetic similarity of 16S rRNA gene sequence. This isolate could utilize biphenyl as sole source of carbon and energy, which degraded over 95 mg/L biphenyl within 36 h. The major metabolites formed from biphenyl, such as 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) and benzoic acid, were identified by LC-MS. The crude cell extract of strain LA-4 exhibited the activity of 2,3-dihydroxybiphenyl 1,2-dioxygenase (2,3-DHBD) and the kinetic parameters were Km= 26.48 μmol/L and Vmax= 8.12 μmol/mg protein. A conserved region of the biphenyl dioxygenase gene bphA1 of strain LA-4 was amplified by PCR and confirmed by DNA sequencing.

  4. Perception of trigeminal mixtures.

    Science.gov (United States)

    Filiou, Renée-Pier; Lepore, Franco; Bryant, Bruce; Lundström, Johan N; Frasnelli, Johannes

    2015-01-01

    The trigeminal system is a chemical sense allowing for the perception of chemosensory information in our environment. However, contrary to smell and taste, we lack a thorough understanding of the trigeminal processing of mixtures. We, therefore, investigated trigeminal perception using mixtures of 3 relatively receptor-specific agonists together with one control odor in different proportions to determine basic perceptual dimensions of trigeminal perception. We found that 4 main dimensions were linked to trigeminal perception: sensations of intensity, warmth, coldness, and pain. We subsequently investigated perception of binary mixtures of trigeminal stimuli by means of these 4 perceptual dimensions using different concentrations of a cooling stimulus (eucalyptol) mixed with a stimulus that evokes warmth perception (cinnamaldehyde). To determine if sensory interactions are mainly of central or peripheral origin, we presented stimuli in a physical "mixture" or as a "combination" presented separately to individual nostrils. Results showed that mixtures generally yielded higher ratings than combinations on the trigeminal dimensions "intensity," "warm," and "painful," whereas combinations yielded higher ratings than mixtures on the trigeminal dimension "cold." These results suggest dimension-specific interactions in the perception of trigeminal mixtures, which may be explained by particular interactions that may take place on peripheral or central levels.

  5. Perception of trigeminal mixtures.

    Science.gov (United States)

    Filiou, Renée-Pier; Lepore, Franco; Bryant, Bruce; Lundström, Johan N; Frasnelli, Johannes

    2015-01-01

    The trigeminal system is a chemical sense allowing for the perception of chemosensory information in our environment. However, contrary to smell and taste, we lack a thorough understanding of the trigeminal processing of mixtures. We, therefore, investigated trigeminal perception using mixtures of 3 relatively receptor-specific agonists together with one control odor in different proportions to determine basic perceptual dimensions of trigeminal perception. We found that 4 main dimensions were linked to trigeminal perception: sensations of intensity, warmth, coldness, and pain. We subsequently investigated perception of binary mixtures of trigeminal stimuli by means of these 4 perceptual dimensions using different concentrations of a cooling stimulus (eucalyptol) mixed with a stimulus that evokes warmth perception (cinnamaldehyde). To determine if sensory interactions are mainly of central or peripheral origin, we presented stimuli in a physical "mixture" or as a "combination" presented separately to individual nostrils. Results showed that mixtures generally yielded higher ratings than combinations on the trigeminal dimensions "intensity," "warm," and "painful," whereas combinations yielded higher ratings than mixtures on the trigeminal dimension "cold." These results suggest dimension-specific interactions in the perception of trigeminal mixtures, which may be explained by particular interactions that may take place on peripheral or central levels. PMID:25500807

  6. Effects of maternal ingestion of aroclor 1254 (PCB) on the development pattern of oxygen consumption and body temperature in neonatal rats

    Energy Technology Data Exchange (ETDEWEB)

    Seo, B.W.; Meserve, L.A. [Bowling Green State Univ., OH (United States)

    1995-07-01

    Polychlorinated biphenyl (PCB) is an environmental pollutant that has been implicated in depression of reproductive success in Great Lakes gulls, production of congenital deformities in humans, and increased incidence of carcinogenesis in laboratory mice. PCB has also been shown to be a thyrotoxin in both adult and developing animals. Most recently, the hypothyroid effects of PCB exposure have been reported to elicit effects similar to those of hypothyroidism caused by other methods. This study was done to determine the effects of PCB ingestion in pregnant and lactating rats on the development of thermoregulation in neonatal animals. Body temperature and rate of oxygen consumption was evaluated in rat puts on days 4 through 14 after birth. Because the major thermomregulatory hormones are thyroid hormones, thyroid hormone status and thyroid weights were evaluated at the end of the study on postnatal day 15. 19 refs., 2 figs., 1 tab.

  7. Levels of polychlorinated biphenyls in 1,4-dichlorobenzene mothballs

    Institute of Scientific and Technical Information of China (English)

    LIU Wen-bin; ZHENG Ming-hui; XING Ying; WANG Dong-sheng; ZHAO Xing-ru; GAO Li-rong

    2005-01-01

    Although polychlorinated biphenyls(PCBs) are globally recognized pollutant, an understanding of their resources as by-products in chemical industry is poorly investigated. This paper presents data from a study that was conducted in order to determine the extent of PCBs in 1,4-dichlorobenzene(p-DCB) mothballs. Total PCBs and dioxin-like PCBs were detected in five mothball samples. Total PCB concentrations ranged from 328 ng/g to 1798 ng/g, while the levels of WHO-TEQ were between 0.16 pg/g and 13 pg/g. Mean concentrations of total PCBs and WHO-TEQ in the samples were 724 ng/g and 3.2 pg/g, respectively. The highest level of PCB congeners was that of trichlorinated biphenyls(537 ng/g), which maybe due to the relatively low chlorination in the process of p-DCB production. A mechanism of the formation of PCBs from polychlorinated benzene in the presence of chlorine is also suggested. The results suggested that re-estimation on the risk of p-DCB products, especially the products for daily use such as mothballs, is expected.

  8. Polychlorinated biphenyl residues in sandstorm depositions in Beijing, China.

    Science.gov (United States)

    Fu, Shan; Yang, Zhong-Zhi; Li, Ke; Xu, Xiao-Bai

    2008-10-01

    Sandstorms, which distribute many particles, are a special atmospheric occurrence and are frequent in northern China. We conducted this study to determine, for the first time, the concentration of polychlorinated biphenyls (PCBs) in sandstorm depositions. We collected 13 samples from urban areas of Beijing, and we measured a total of 144 PCB congeners. Thirteen samples all contained PCB residues. The total PCB concentration ranged from 1.6 to 15.6ngg(-1) (median, 4.8ngg(-1), dry weight), with trichlorinated biphenyls as the predominant homologue (>50.4%). Furthermore, we observed increasing PCB contamination from northwest to east Beijing. We later explored possible factors affecting contamination of the sandstorm depositions, which revealed a significant correlation between SigmaPCBs and the minimum particle size of the sandstorm deposition samples. Principal-component analysis revealed that the major source of PCBs in Beijing may be potentially associated with the number-one commercial PCB through the long-range transmission. In previous results, PCBs were not a severe component of contamination in sandstorm depositions of Beijing. However, this study suggested that sandstorm deposition may be a potential source of exposure to PCBs for the residents of Beijing, China. PMID:18674798

  9. Extraction equilibria of trimellitic and [1,1'-Biphenyl]-2,2'-dicarboxylic Acid with 1-Octanol, 50%TBP, and 10%TRPO in Kerosene%正辛醇、50%TBP/煤油和10%TRPO/煤油对偏苯三甲酸和2,2'-联苯二甲酸的萃取平衡

    Institute of Scientific and Technical Information of China (English)

    周智勇; 秦炜; 戴猷元

    2008-01-01

    To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1'-biphenyl]-2,2'-dicarboxylic acid, were selected as the solutes, and the extraction equilibrium of the acids were studied with 1-octanol, 50% tributyl phosphate (TBP) in kerosene, and 10% trialkylphosphine oxide (TRPO) in kerosene. The results showed that the degree of extraction of [1,1'-biphenyl]-2,2'-dicarboxylic acid was larger than that of trimellitic acid for all of the solvent, and the extraction capacity with TRPO is more effective than the one with TBP. The extraction behavior of aromatic polyacid is different from that of carboxylic acid, and the reactive extraction function of aromatic acids with TBP and TRPO is not as effective as that of carboxylic acid. 1-octanol could be used to remove [1,1'-biphenyl]-2,2'-dicarboxylic acid from the mixture of trimellitic acid and [1,1'-biphenyl]-2,2'-dicarboxylic acid. Because the weak hydrogen bond association exists between -OH in 1-octanol and -COOH in aromatic acid, the extractive selectivity of [1,1'-biphenyl]-2,2'-dicarboxylic to trimellitic acid depends on the stoichiometric ratio.

  10. Internal Reorganization Energy Contributed by Torsional Motion in Electron Transfer Reaction between Biphenyl and Biphenyl Anion Radical

    Institute of Scientific and Technical Information of China (English)

    MIN,Wei(闵玮); SUN,Lin(孙琳)

    2002-01-01

    Concerning the theoretical estimation of internal reorganization energy contributed by the tortional motion between biphenyl and biphenyl anion radical, direct calculation of self-exchange electron transfer reaction was investigated. With the introduction of a proper average bond length and angle parameters < bond Bp > , a multiple step relaxation Nelson method was developed to deal with the torsional reoganization energy.Based on the above model, an estimation of pure torsional reorganization energy λt,p with an approximation of λt,1 was achieved. The results of 0.140 and 0.125 eV of torsional reorganization energy for a cross-reaction at the levels of 4-31G and HP/DZP, respectively, are in good agreement with the value of 0.13 eV obtained by Miller et al. from the rate measurements. This implies the efficiency and validity of our method to estinate the reorganization energy contributed by pure torsional motion of Bp.

  11. Mechanistic insights on the hydrodesulfurization of biphenyl-2-thiol with nickel compounds.

    Science.gov (United States)

    Torres-Nieto, Jorge; Brennessel, William W; Jones, William D; García, Juventino J

    2009-03-25

    The reactivity of the nickel(I) dimer [(dippe)Ni(mu-H)](2) (1) with biphenyl-2-thiol was explored with the aim of clarifying the key step of sulfur extrusion during the hydrodesulfurization process using dibenzothiophene (DBT). These reactions were monitored by variable temperature NMR experiments which allowed the complete characterization and isolation of [(dippe)(2)Ni(2)(mu-H)(mu-S-2-biphenyl)] (3). The latter compound evolves to the terminal nickel-hydride [(dippe)Ni (eta(1)-C-2-biphenyl)(H)] (4) and transient [(dippe)NiS] (5), to ultimately yield [(dippe)(2)Ni(2)(mu-S)] (2) and biphenyl as the resulting HDS products. The reactivity of 1 and biphenyl-2-thiol was examined using different ratios of reactants, which allowed preparation of [(dippe)Ni(eta(1)-S-biphenyl-2-thiolate)(2)] (6) when using an excess of this substrate. The reactivity of 6 with 1 was addressed, yielding compound 2 and an equivalent amount of biphenyl. PMID:19292493

  12. Effects on thyroid hormone and retinoid metabolism in transthyretin-null mice by polychlorinated biphenyl isomers 118 and 114

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, N.; Yonemoto, J.; Takeuchi, Y.; Yokoi, C.; Tohyama, C. [National Inst. for Environmental Studies, Tsukuba (Japan)

    2004-09-15

    Some congeners/isomers of polychlorinated biphenyls (PCBs) and their metabolites are known to disturb thyroid and retinoid metabolism in laboratory animals and humans. Among 209 isomers of PCBs, 12 PCB isomers termed as the coplanar PCBs are grouped into dioxin-like chemicals based on their resemblance of toxic effects and mechanism(s) to dioxins. Mechanism(s) of toxicity by the dioxin-like chemicals have been established to be mediated through aryl hydrocarbon receptor (AhR). The toxic potency of each congener/isomer of dioxin-like chemicals has been evaluated by relative potency to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as the toxic equivalent factor (TEF). Because dioxins in environments are generally distributed as mixtures, the toxic equivalency (TEQ) concept has been adopted to evaluate the health risk of exposure to complex environmental mixtures. TEQ values are calculated by multiplication of the sum of the chemical concentrations by the corresponding TEF values. The present study was undertaken to investigate the effects of two coplanar PCBs, PCB118, highly detected in human tissues and milk (TEF value: 0.0001), and PCB114 (TEF value: 0.0005) on thyroid hormone and retinoid metabolism. Possible involvement of transthyretin (TTR), the principal carrier of thyroid hormone and retinol-binding protein in the rodent, in PCBs-induced disruption of thyroid and retinoid homeostasis was investigated.

  13. Sources and Distribution of Polychlorinated Terphenyls at a Major US Aeronautics Research Facility.

    Science.gov (United States)

    HALE; ENOS; GALLAGHER

    1998-11-01

    / High concentrations of an unusual, complex mixture of chlorinated compounds were discovered in sediments and oysters near a federal aeronautics facility during implementation of a pollutant screening protocol. The mixture was identified as Aroclor 5432, a polychlorinated terphenyl (PCT) formulation, produced in the US until 1972. PCTs, particularly low chlorinated mixtures, have rarely been reported in the environment, despite significant manufacture and usage. Releases were traced to two outfalls. Creek sediments downstream of one contained concentrations as high as 200,000 |gmg/kg (dry weight basis); those in indigenous oysters reached 35,000 |gmg/kg, indicating significant bioavailability and bioaccumulation potential. Subsequent work showed that PCTs were widely disseminated in marsh grass, crabs, and fish. PCTs, PCBs, and mercury were also detected in storm drain lines entering these outfalls. The lines received input from both storm water and research buildings. Historical hydraulic fluid leaks and in-service compressor fluids in some buildings contained PCTs and PCBs. Contaminated materials on-site were removed to minimize pollutant spread. Aroclor 5432 usage, most likely as compressor/hydraulic fluid additives, probably ended about ten years prior to its on-site detection. In terms of biological effects, intraperitoneal injection of fish with Aroclor 5432 induced cytochrome P-4501A (CYP1A) and ethoxyresorufin O-deethylase (EROD) activity to a similar degree as PCB Aroclor 1254 and to a greater extent than PCT Aroclor 5460. The presence of high concentrations of PCTs contributed to the facility being included on the National Priorities List. It subsequently became the first US federal facility to sign a Federal Facility Agreement, identifying cleanup responsibilities, prior to formal listing.KEY WORDS: Polychlorinated terphenyls; Aroclor; Contaminated sediments; Hydraulic fluid; Enzyme induction; Polychlorinated biphenyls

  14. Attenuating effect of daidzein on polychlorinated biphenyls-induced oxidative toxicity in mouse testicular cells

    Institute of Scientific and Technical Information of China (English)

    Da-lei ZHANG; Yu-ling MI; Kai-ming WANG; Wei-dong ZENG; Cai-qiao ZHANG

    2008-01-01

    The attenuating effect of daidzein (DAD on oxidative toxicity induced by Aroclor 1254 (A 1254) was investigated in mouse testicular cells. Cells were exposed to A1254 alone or with DAI. The oxidative damage was estimated by measuring malondialdehyde (MDA) formation, superoxide dismutase (SOD) activity and glutathione (GSH) content. Results show that A 1254 induced a decrease of germ cell number, an elevation in thiobarbituric acid reactive substances (TBARS) but a decrease in SOD activity and GSH content. However, simultaneous supplementation with DAI decreased TBARS level and increased SOD activity and GSH content. Consequently, dietary DAI may restore the intracellular antioxidant system to attenuate the oxidative toxicity of A1254 in testicular cells.

  15. Synthesis of P,N-2,2’-biphenyl derivatives with central chirality

    Institute of Scientific and Technical Information of China (English)

    JEAN; Ludovic; POULIQUEN; Michael; BLANCHET; Jér?me; LASNE; Marie-Claire; ROUDEN; Jacques

    2010-01-01

    Enantiopure 2-(dicyclohexylphosphino)-1,1’-biphenyl derivatives substituted in the 2’-position by a chiral amino group were prepared.For the compound bearing an acyclic chiral chain,the key step was a Suzuki coupling between bromobenzeneboronic acid and N-Boc-iodoaniline whereas an aromatic nucleophilic substitution allowed the introduction of a chiral pyrrolidine in the 2’-position of the biphenyl backbone.The efficiency of the P,N-biphenyl pyrrolidine derivatives as ligands in Pd-catalyzed arylaminations compares well with that of DavePhos ligand.

  16. Multilevel Mixture Kalman Filter

    Directory of Open Access Journals (Sweden)

    Xiaodong Wang

    2004-11-01

    Full Text Available The mixture Kalman filter is a general sequential Monte Carlo technique for conditional linear dynamic systems. It generates samples of some indicator variables recursively based on sequential importance sampling (SIS and integrates out the linear and Gaussian state variables conditioned on these indicators. Due to the marginalization process, the complexity of the mixture Kalman filter is quite high if the dimension of the indicator sampling space is high. In this paper, we address this difficulty by developing a new Monte Carlo sampling scheme, namely, the multilevel mixture Kalman filter. The basic idea is to make use of the multilevel or hierarchical structure of the space from which the indicator variables take values. That is, we draw samples in a multilevel fashion, beginning with sampling from the highest-level sampling space and then draw samples from the associate subspace of the newly drawn samples in a lower-level sampling space, until reaching the desired sampling space. Such a multilevel sampling scheme can be used in conjunction with the delayed estimation method, such as the delayed-sample method, resulting in delayed multilevel mixture Kalman filter. Examples in wireless communication, specifically the coherent and noncoherent 16-QAM over flat-fading channels, are provided to demonstrate the performance of the proposed multilevel mixture Kalman filter.

  17. Vapor solvent decontamination of PCB [polychlorinated biphenyls] transformer components

    International Nuclear Information System (INIS)

    A process is provided to recover reclaimable material from discarded transformers containing PCB (polychlorinated biphenyl) insulating oils and to minimize the volume of materials which are subject to environmental regulation upon disposal. According to the invention, the transformer is drained and given an initial cleaning. The internal parts are removed and cleaned a second time as is the empty transformer casing. Recoverable materials such as aluminum and copper are cleaned to less than 10 μg of PCB per 100 cm2, allowing these materials to be recycled rather than buried. Almost all of the remaining nonmetallic materials are combustible solids or liquids which can be destroyed by incineration. The cleaning is accomplished using trichloroethylene solvent, chosen for its low boiling point which makes it easy to recycle using an isothermal separator. The removed transformer parts are cleaned in a secondary cleaning station consisting of 3 separate sections including tumbling baskets. 2 figs

  18. Fluorescence characteristics of polychlorinated biphenyl isomers in cyclodextrin media

    Energy Technology Data Exchange (ETDEWEB)

    Femia, R.A.; Scypinski, S.; Love, L.J.C.

    1985-01-01

    The fluorescence characteristics of several polychlorinated biphenyl (PCB) isomers in ..cap alpha..- and ..beta..-cyclodextrin (CD) are discussed and contrasted. The steric hindrance of PCBs imposed by the positions of the chlorine atoms on the rings determines the overall stability of the resulting inclusion complexes with cyclodextrin which is reflected in the fluorescence intensities. Less substituted homologues include into the CD cavity equally well in both cyclodextrins, but very heavily substituted molecules show drastic differences between their fluorescence intensities in the ..cap alpha..- and ..beta..-cyclodextrin solutions. This behavior can be employed as a method for spectral fractionation of PCB isomers. Spectral separation is demonstrated here for two variably substituted molecules, and the photophysical limitations of this approach are discussed.

  19. Bis(4-carbamoylpiperidinium biphenyl-4,4′-disulfonate

    Directory of Open Access Journals (Sweden)

    Graham Smith

    2010-12-01

    Full Text Available In the title isonipecotamide salt 2C6H13N2O+·C12H8O6S22−, the asymmetric unit comprises one biphenyl-4,4′-disulfonate dianion which lies across a crystallographic inversion centre and another in a general position [dihedral angle between the two phenyl rings is 37.1 (1°], together with three isonipecotamide cations. Two of these cations give a cyclic homomeric amide–amide dimer interaction [graph set R22(8], the other giving a similar dimeric interaction but across an inversion centre, both dimers then forming lateral cyclic R42(8 pyrimidinium–amide N—H...O interactions. These units are linked both laterally and longitudinally to the sulfonate groups of the dianions through piperidinium N—H...O hydrogen bonds, giving a three-dimensional framework structure.

  20. Guidance on the management of polychlorinated biphenyls (PCBs)

    Energy Technology Data Exchange (ETDEWEB)

    1993-11-01

    Polychlorinated biphenyls (PCBs) are a class of synthetic organic chemicals including 209 known isomers, each with from 1 to 10 chlorine atoms on a biphenyl ring. PCBs have a number of desirable properties for industrial applications including thermal stability, flame retardance, and low vapor pressure. Because of these properties, PCBs were widely used as dielectric fluid in electrical equipment such as utility transformers and capacitors. PCBs were also extensively used in hydraulic fluid and heat transfer fluid, in gaskets, as additives in cutting oils and lubricant, and in a variety of other uses. The Toxic Substances Control Act (TSCA) banned the manufacture of PCBs after 1978 in response to emerging information about the adverse health effects of PCBs and their persistence in the environment. In addition, TSCA directed the Administrator of the Environmental Protection Agency (EPA) to prescribe methods for disposal of PCBS, require marking of PCBs with warning labels, and control their use. The TSCA regulations allow continued use of PCBs provided that the use is totally enclosed and does not pose a risk to human health or the environment. However, at the end of their useful life, all PCB materials must be disposed of according to the TSCA regulations. This guidance document uses graphics and flow charts where possible to present the TSCA regulations according to management activities such as use, storage, disposal, and spill cleanup. The document is designed to be read on an as-needed basis; that is, each chapter can stand alone or may be read in combination with others to help the reader determine the regulations relevant to his or her individual situation and needs. Every attempt has been made to include the requirements of other statutes and regulations that apply to PCB materials and provide references for the reader to consult for additional information.

  1. Chronic treatment with polychlorinated biphenyls (PCB) during pregnancy and lactation in the rat

    International Nuclear Information System (INIS)

    The gender-specific expression pattern of aromatase and 5alpha-reductases (5alpha-R) during brain development provides neurons the right amount of estradiol and DHT to induce a dimorphic organization of the structure. Polychlorinated biphenyls (PCBs) are endocrine disruptive pollutants; exposure to PCBs through placental transfer and breast-feeding may adversely affect the organizational action of sex steroid, resulting in long-term alteration of reproductive neuroendocrinology. The study was aimed at: a) evaluating the hypothalamic expression of aromatase, 5alpha-R1 and 5alpha-R2 in fetuses (GD20), infant (PN12), weaning (PN21) and young adult (PN60) male and female rats exposed to PCBs during development; b) correlating these parameters with the time of testicular descent, puberty onset, estrous cyclicity and copulatory behavior; c) evaluating possible alterations of some non reproductive behaviors (locomotion, learning and memory, depression/anxiety behavior). A reconstituted mixture of four indicator congeners (PCB 126, 138, 153 and 180) was injected subcutaneously to dams at the dose of 10 mg/kg daily from GD15 to GD19 and then twice a week till weanling. The results indicated that developmental PCB exposure produced important changes in the dimorphic hypothalamic expression of both aromatase and the 5alpha-Rs, which were still evident in adult animals. We observed that female puberty onset occurs earlier than in control animals without cycle irregularity, while testicular descent in males was delayed. A slight but significant impairment of sexual behavior and an important alteration in memory retention were also noted specifically in males. We conclude that PCBs might affect the dimorphic neuroendocrine control of reproductive system and of other neurobiological processes.

  2. Polychlorinated biphenyl (PCB) induction of CYP3A4 enzyme activity in healthy Faroese adults

    International Nuclear Information System (INIS)

    The CYP3A4 enzyme is, along with other cytochrome P450 enzymes, involved in the metabolism of environmental pollutants and is highly inducible by these substances. A commercial polychlorinated biphenyl (PCB) mixture, 1,1,1,-trichloro-2-(o-chlorophenyl), 2-(p'-chlorophenyl)ethane (o,p'-DDT) and 1,1,-dichloro-2,2-bis (p-chlorophenyl)ethene (p,p'-DDE) are known to induce CYP3A4 activity through activation of nuclear receptors, such as the pregnane X receptor. However, this induction of CYP3A4 has not yet been investigated in humans. Thus, the aim of the study was to determine the variability of the CYP3A4 phenotype in regard to increased concentrations of PCBs and other persistent organohalogen pollutants (POPs) in healthy Faroese adults. In 310 randomly selected Faroese residents aged 18-60 years, the CYP3A4 activity was determined based on the urinary 6β-hydroxycortisol/cortisol (6β-OHC/FC) ratio. POP exposures were assessed by measuring their concentrations in serum lipid. The results showed a unimodal distribution of the 6β-OHC/FC ratio with values ranging from 0.58 to 27.38. Women had a slightly higher 6β-OHC/FC ratio than men (p = 0.07). Confounder-adjusted multiple regression analysis showed significant associations between 6β-OHC/FC ratios and ΣPCB, PCB-TEQ and p,p'-DDE, o,p'-DDT and HCB, respectively, but the associations were statistically significant for men only

  3. Atropisomerism in a new type biphenyl and o-terphenyl condensed tannins

    International Nuclear Information System (INIS)

    Chemical investigation of the core wood Prosopis glandulosa has revealed that it has a complex flavenoid content. The predominant phenolic component of the core wood is flavan-3-ol with a 3,,4,,7,8-tetrahydroxy phenolic substitute pattern. Apart from the isolation of 'conventionally' coupled biflavenoids based on electrophilic attack at the C4-carbeniumion from flavan-3,4-diol on the nucleophilic positions of flavan-3-ols, a new 1-flavenyl-1,3-diarylpropan-2-ol as wel as a B-ring coupled flavenyl-2-benzoylbenzofuran was isolated. The uniqueness of this study lies in the identification of [5,6]-coupled and atropisomeric [5,5]-biflavenoids based on a biphenyl bond which was extended to the triflavenoid level with the identification of four [5,5:5,6]-0-terphenyl triflavenoidatropisomers. The 1H nmr spectra of the 5,5-dimers and [5,5:5,6]-trimers exhibit sharply defined spectra at room temperatures which suggests rigidity of structure at these temperatures. Further proof of atropisomerism at the [5,5]-coupled dimers was obtained by means of an isomerization experiment. At the [5,6]-coupled isomers, a dynamic equilibrium at the 1H nmr-spectra of the methyl etheracetate derivatives was observed. Synthesis of the optically pure [4,6]-biflavenoid with 3,,4,,7,8-tetrahydroxylation pattern was, conducted through reduction of (+-)-3,,4,7,8-tetramethoxydihydroflavonol, condensation of it to the monomeric (+)-3,,4,,7,8-tetrahydroxyflavan-3-ol and subsequent separation of the diastereo-isomeric mixture

  4. Environmental Polychlorinated Biphenyl Exposure and Breast Cancer Risk: A Meta-Analysis of Observational Studies.

    Directory of Open Access Journals (Sweden)

    Jingwen Zhang

    Full Text Available Association between polychlorinated biphenyl (PCB exposure and breast cancer risk has been widely studied, but the results remain controversial. We performed a meta-analysis to evaluate the evidences from observational studies on PCB exposure and breast cancer risk.Relevant studies with data on internal PCB dose were identified from PubMed, EMBASE, CBM and CNKI databases through November 2014. Multivariable-adjusted odds ratio (OR with 95% confidence intervals (CIs were applied to assess the association between PCB exposure and breast cancer risk. Heterogeneity test, sensitivity analysis, subgroup analysis and publication bias test were also performed. To further explore the association between specific groups of PCB congeners and breast cancer, we examined the PCB congeners classified, according to their structural, biological and pharmacokinetics properties, as group I (potentially estrogenic, group II (potentially anti-estrogenic and immunotoxic, dioxin-like, and group III (phenobarbital, CYP1A and CYP2B inducers, biologically persistent.Of 660 studies screened, 25 studies which met criteria were selected, involving a total of 12866 participants (6088 cases and 6778 controls from eight countries. The results showed that the risk of breast cancer was associated with group II (OR = 1.23, 95% CI: 1.08-1.40 and group III (OR = 1.25, 95% CI: 1.09-1.43 PCBs, but not with group I (OR = 1.10, 95%CI: 0.97-1.24 PCBs or total PCB exposure (OR = 1.09, 95%CI: 0.97-1.22.Our meta-analysis based on the selected studies found group II and group III PCB exposure might contribute to the risk of breast cancer. More studies in developing countries with higher PCB levels are needed, as well as studies to explore the relationships between mixtures of organochlorine compounds and breast cancer risk.

  5. The levels of polychlorinated biphenyls in 1,4-dichlorobenzene mothballs

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wenbin; Zheng, Minghui; Xing, Ying; Wang, Dongshen; Zhao, Xingru; Gao, Lirong [Chinese Academy of Sciences, Beijing (China). Key laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences

    2004-09-15

    The chemical 1,4-dichlorobenzene (p-DCB), also called paramoth, is one of the chemicals commonly used to make mothballs. For the more than 20 years, p-DCB has been used principally (35-55% of all uses) as a space deodorant for toilets and refuse containers, and as a fumigant for control of moths, molds, and mildews. The process of production of p-DCB currently used by industry is direct chlorination of benzene or chlorobenzene in the presence of a Friedel-Crafts catalyst (typically FeCl{sub 3}), and the pure products of p-DCB are obtained by distillation and crystallization from the mixture of polychlorinated benzenes. This process is similar to that of production of PCBs which were manufactured commercially by the progressive chlorination of biphenyl in the presence of a suitable catalyst, e.g., iron chloride. However, few studies on the formation of PCBs from chlorobenzenes have been published. Buser reported significant quantities of PCDFs and a small amount of PCDDs, PCBs, and chlorophenols were formed in the pyrolysis of chlorobenzenes at 620 C. Peng-Yan Liu et al. revealed that lower chlorinated benzenes produce more PCBs than higher ones. Nevertheless, prior to this study, no reports on PCBs in p-DCB and the restriction of PCBs in p-DCB products have been found. In this paper, the occurrence and distribution of dioxin-like PCBs and total PCBs in some commercial p-DCB mothballs are investigated. Except of the toxic of p-DCB, the low concentration of PCBs in p-DCB mothballs should not be negligible.

  6. Mixtures Estimation and Applications

    CERN Document Server

    Mengersen, Kerrie; Titterington, Mike

    2011-01-01

    This book uses the EM (expectation maximization) algorithm to simultaneously estimate the missing data and unknown parameter(s) associated with a data set. The parameters describe the component distributions of the mixture; the distributions may be continuous or discrete. The editors provide a complete account of the applications, mathematical structure and statistical analysis of finite mixture distributions along with MCMC computational methods, together with a range of detailed discussions covering the applications of the methods and features chapters from the leading experts on the subject

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

    DEFF Research Database (Denmark)

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

    2009-01-01

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

  8. COMPARING POLYCHLORINATED BIPHENYLS IN FARM-RAISED AND WILD-CAUGHT CATFISH FROM SOUTHERN MISSISSIPPI

    Science.gov (United States)

    Polychlorinated biphenyls (PCBs) are among the most thermally stable organic chemicals known. This characteristic has historically made them useful in a wide array of applications including use in electrical transformers and capacitors, varnishes, waxes, synthetic resins, epoxy ...

  9. Immunologic effects of background exposure to polychlorinated biphenyls and dioxins in Dutch preschool children

    NARCIS (Netherlands)

    N. Weisglas-Kuperus (Nynke); S. Patandin (Svati); G.A. Berbers; T.C.J. Sas (Theo); P.J.J. Sauer (Pieter); H. Hooijkaas (Herbert); P.G.H. Mulder (Paul)

    2000-01-01

    textabstractPrenatal exposure to polychlorinated biphenyls (PCBs) and dioxins is associated with changes in the T-cell lymphocyte population in healthy Dutch infants. We investigated whether these changes persist into later childhood and whether background exposure to P

  10. Polychlorinated biphenyl (PCB) removal from the Kenai National Wildlife Refuge, Alaska, October 1984 and 1988

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the removal of polychlorinated biphenyl (PCB) from Kenai National Wildlife Refuge in Alaska during October 1984 and 1985. Atlantic Ritchfield...

  11. 78 FR 20640 - Polychlorinated Biphenyls (PCBs); Recycling Plastics from Shredder Residue

    Science.gov (United States)

    2013-04-05

    ... AGENCY Polychlorinated Biphenyls (PCBs); Recycling Plastics from Shredder Residue AGENCY: Environmental... will generally allow for the recycling of plastic separated from shredder residue under the conditions described in the Voluntary Procedures for Recycling Plastics from Shredder Residue, relying principally...

  12. METHODS FOR DETERMINING THE POLYCHLORINATED BIPHENYL EMISSIONS FROM INCINERATION AND CAPACITOR AND TRANSFORMER FILLING PLANTS

    Science.gov (United States)

    Described are methods to measure the polychlorinated biphenyl (PCB) emissions from the stacks of municipal waste, industrial waste, and sewage sludge incinerators and from capacitor and transformer filling plants. The PCB emissions from the incineration plants are collected by im...

  13. POLYCHLORINATED BIPHENYLS IN HOUSE DUST AND YARD SOIL NEAR A SUPERFUND SITE. (R825173)

    Science.gov (United States)

    Polychlorinated biphenyls (PCBs) were measured in house dust and yard soil at 34 homes surrounding New Bedford Harbor during dredging of highly contaminated harbor sediments. PCBs can volatilize from sediments and seawater and subsequently deposit on surrounding soil, resulting i...

  14. I-optimal mixture designs

    OpenAIRE

    Goos, Peter; JONES, Bradley; SYAFITRI, Utami

    2013-01-01

    In mixture experiments, the factors under study are proportions of the ingredients of a mixture. The special nature of the factors in a mixture experiment necessitates specific types of regression models, and specific types of experimental designs. Although mixture experiments usually are intended to predict the response(s) for all possible formulations of the mixture and to identify optimal proportions for each of the ingredients, little research has been done concerning their I-optimal desi...

  15. Mixtures and interactions

    NARCIS (Netherlands)

    Groten, J.P.

    2000-01-01

    Drinking water can be considered as a complex mixture that consists of tens, hundreds or thousands of chemicals of which the composition is qualitatively and quantitatively not fully known. From a public health point of view it is most relevant to answer the question of whether chemicals in drinking

  16. Novel Ring Cleavage Products in the Biotransformation of Biphenyl by the Yeast Trichosporon mucoides

    OpenAIRE

    Sietmann, Rabea; Hammer, Elke; Specht, Michael; Carl E Cerniglia; Schauer, Frieder

    2001-01-01

    The yeast Trichosporon mucoides, grown on either glucose or phenol, was able to transform biphenyl into a variety of mono-, di-, and trihydroxylated derivatives hydroxylated on one or both aromatic rings. While some of these products accumulated in the supernatant as dead end products, the ortho-substituted dihydroxylated biphenyls were substrates for further oxidation and ring fission. These ring fission products were identified by high-performance liquid chromatography, gas chromatography-m...

  17. Investigation of mechanisms of formation of biphenyls and benzonaphthothiophenes by simulation experiment

    Institute of Scientific and Technical Information of China (English)

    XIA; Yanqing(夏燕青); ZHANG; Gengxin(张更新)

    2002-01-01

    The formation mechanisms of biphenyl series and benzonaphthothiophene series are investigated by means of simulation experiment. Biphenyl series are likely formed in two ways: one is the aromatization of the chain compounds containing conjugated C== C double bonds or the compounds with such a kind of sidechains, and the other is the reaction of sulfur with ordinary chain compounds, in which sulphur acts on ordinary sidechain compounds by seizing some hydrogens and forming (H2S and) the intermediates with conjugated C== C double bonds first, and then the intermediates are aromatized. One of the basic precursors of benzonaphthothiophenes is likely the phenylnaphthalenes which may originate from the chain compounds containing conjugated C== C double bonds, the compounds with such sidechains and saturate or unsaturate chain compounds. Thermal stability of biphenyls is high, but they can become dibenzothiophenes and polycyclic aromatic hydrocarbons or dibenzofurans and polycyclic aromatic hydrocarbons respectively in the presence of sulphur or oxygen. The ratio of biphenyl and m-biphenyl to biphenyls may be employed to indicate the depositional environment in the mild to medium maturation, of which the higher value indicates a fresh water depositional environment and the lower indicates a saline depositional environment. The relative high content of benzonaphthothiophenes in the crude oil indicates that the crude oil has undergone an intense sulfurization in the source rock or reservoir.

  18. Investigation of saponification for determination of polychlorinated biphenyls in marine sediments.

    Science.gov (United States)

    Numata, Masahiko; Yarita, Takashi; Aoyagi, Yoshie; Yamazaki, Misako; Takatsu, Akiko

    2005-02-01

    The effects of saponification conditions (temperature and water content of saponifying solution) on the determination of chlorinated biphenyls (CBs) in marine sediments were investigated. Although highly chlorinated biphenyls (nona- to deca-CBs) decomposed during high-temperature saponification, the degree of degradation was reduced by adding water to the ethanolic potassium hydroxide saponifying solution. Room-temperature saponification yielded quantitative recovery of highly chlorinated biphenyl surrogates but low extraction efficiencies of lightly chlorinated biphenyls (mono- to di-CBs). The same samples were analyzed by other extraction techniques, for example, pressurized liquid extraction, and analytical results were compared. The mono- and di-CB concentrations were correlated with the extraction temperatures of various extraction techniques. In particular, the concentrations of some CB congeners (CB11, CB14) were higher with saponification. The low degree of degradation of highly chlorinated biphenyls and the high recovery of lightly chlorinated biphenyls were compatible when room-temperature and high-temperature saponification were combined. Except for the anomalies of CB11 and CB14, the combined method gave satisfactory results for analysis of PCBs.

  19. Regional analysis of potential polychlorinated biphenyl degrading bacterial strains from China.

    Science.gov (United States)

    Shuai, Jianjun; Yu, Xurun; Zhang, Jing; Xiong, Ai-Sheng; Xiong, Fei

    2016-01-01

    Polychlorinated biphenyls (PCBs), the chlorinated derivatives of biphenyl, are one of the most prevalent, highly toxic and persistent groups of contaminants in the environment. The objective of this study was to investigate the biodegradation of PCBs in northeastern (Heilongjiang Province), northern (Shanxi Province) and eastern China (Shanghai municipality). From these areas, nine soil samples were screened for PCB-degrading bacteria using a functional complementarity method. The genomic 16S rDNA locus was amplified and the products were sequenced to identify the bacterial genera. Seven Pseudomonas strains were selected to compare the capacity of bacteria from different regions to degrade biphenyl by HPLC. Compared to the biphenyl content in controls of 100%, the biphenyl content went down to 3.7% for strain P9-324, 36.3% for P2-11, and 20.0% for the other five strains. These results indicate that a longer processing time led to more degradation of biphenyl. PCB-degrading bacterial strains are distributed differently in different regions of China. PMID:27140507

  20. Differential effects of a complex organochlorine mixture on the proliferation of breast cancer cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Aube, Michel, E-mail: 4aubem@videotron.ca [Axe de recherche en sante des populations et environnementale, Centre de recherche du Centre hospitalier universitaire de Quebec and Universite Laval, 2875 Boulevard Laurier, Edifice Delta 2, bureau 600, Quebec, QC, Canada G1V 2M2 (Canada); Larochelle, Christian, E-mail: christian.larochelle@inspq.qc.ca [Axe de recherche en sante des populations et environnementale, Centre de recherche du Centre hospitalier universitaire de Quebec and Universite Laval, 2875 Boulevard Laurier, Edifice Delta 2, bureau 600, Quebec, QC, Canada G1V 2M2 (Canada); Ayotte, Pierre, E-mail: pierre.ayotte@inspq.qc.ca [Axe de recherche en sante des populations et environnementale, Centre de recherche du Centre hospitalier universitaire de Quebec and Universite Laval, 2875 Boulevard Laurier, Edifice Delta 2, bureau 600, Quebec, QC, Canada G1V 2M2 (Canada); Laboratoire de Toxicologie, Institut national de sante publique du Quebec, 945 avenue Wolfe, Quebec, QC, Canada G1V 5B3 (Canada)

    2011-04-15

    Organochlorine compounds (OCs) are a group of persistent chemicals that accumulate in fatty tissues with age. Although OCs has been tested individually for their capacity to induce breast cancer cell proliferation, few studies examined the effect of complex mixtures that comprise compounds frequently detected in the serum of women. We constituted such an OC mixture containing 15 different components in environmentally relevant proportions and assessed its proliferative effects in four breast cancer cell lines (MCF-7, T47D, CAMA-1, MDAMB231) and in non-cancerous CV-1 cells. We also determined the capacity of the mixture to modulate cell cycle stage of breast cancer cells and to induce estrogenic and antiandrogenic effects using gene reporter assays. We observed that low concentrations of the mixture (100x10{sup 3} and 50x10{sup 3} dilutions) stimulated the proliferation of MCF-7 cells while higher concentrations (10x10{sup 3} and 5x10{sup 3} dilutions) had the opposite effect. In contrast, the mixture inhibited the proliferation of non-hormone-dependent cell lines. The mixture significantly increased the number of MCF-7 cells entering the S phase, an effect that was blocked by the antiestrogen ICI 182,780. Low concentrations of the mixture also caused an increase in CAMA-1 cell proliferation but only in the presence estradiol and dihydrotestosterone (p<0.05 at the 50x10{sup 3} dilution). DDT analogs and polychlorinated biphenyls all had the capacity to stimulate the proliferation of CAMA-1 cells in the presence of sex steroids. Reporter gene assays further revealed that the mixture and several of its constituents (DDT analogs, aldrin, dieldrin, {beta}-hexachlorocyclohexane, toxaphene) induced estrogenic effects, whereas the mixture and several components (DDT analogs, aldrin, dieldrin and PCBs) inhibited the androgen signaling pathway. Our results indicate that the complex OC mixture increases the proliferation of MCF-7 cells due to its estrogenic potential. The

  1. Differential effects of a complex organochlorine mixture on the proliferation of breast cancer cell lines

    International Nuclear Information System (INIS)

    Organochlorine compounds (OCs) are a group of persistent chemicals that accumulate in fatty tissues with age. Although OCs has been tested individually for their capacity to induce breast cancer cell proliferation, few studies examined the effect of complex mixtures that comprise compounds frequently detected in the serum of women. We constituted such an OC mixture containing 15 different components in environmentally relevant proportions and assessed its proliferative effects in four breast cancer cell lines (MCF-7, T47D, CAMA-1, MDAMB231) and in non-cancerous CV-1 cells. We also determined the capacity of the mixture to modulate cell cycle stage of breast cancer cells and to induce estrogenic and antiandrogenic effects using gene reporter assays. We observed that low concentrations of the mixture (100x103 and 50x103 dilutions) stimulated the proliferation of MCF-7 cells while higher concentrations (10x103 and 5x103 dilutions) had the opposite effect. In contrast, the mixture inhibited the proliferation of non-hormone-dependent cell lines. The mixture significantly increased the number of MCF-7 cells entering the S phase, an effect that was blocked by the antiestrogen ICI 182,780. Low concentrations of the mixture also caused an increase in CAMA-1 cell proliferation but only in the presence estradiol and dihydrotestosterone (p3 dilution). DDT analogs and polychlorinated biphenyls all had the capacity to stimulate the proliferation of CAMA-1 cells in the presence of sex steroids. Reporter gene assays further revealed that the mixture and several of its constituents (DDT analogs, aldrin, dieldrin, β-hexachlorocyclohexane, toxaphene) induced estrogenic effects, whereas the mixture and several components (DDT analogs, aldrin, dieldrin and PCBs) inhibited the androgen signaling pathway. Our results indicate that the complex OC mixture increases the proliferation of MCF-7 cells due to its estrogenic potential. The proliferative effect of the mixture on CAMA-1 cells in

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-04-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-04-01

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

  4. Atmospheric emission of polychlorinated biphenyls from multiple industrial thermal processes.

    Science.gov (United States)

    Liu, Guorui; Zheng, Minghui; Cai, Mingwei; Nie, Zhiqiang; Zhang, Bing; Liu, Wenbin; Du, Bing; Dong, Shujun; Hu, Jicheng; Xiao, Ke

    2013-03-01

    In this study, field measurements were conducted to estimate and characterize the atmospheric emission levels and profiles of polychlorinated biphenyls (PCBs) from multiple industrial thermal processes. The emission levels and profiles of PCBs from five types of thermal processes at twenty-three plants were studied and compared with eight processes reported in our previous studies. Correlation analysis was preformed to identify a marker congener for emission of ΣPCB. A significant correlation was observed between congener CB-118 and ΣPCB (R(2)=0.65 and pprocesses were compared, and this information could be used for studying source-receptor relationships and identifying the specific sources of PCBs. To prioritize the sources for control, the concentrations of PCBs from thirteen industrial thermal sources were compared. The PCB concentrations from secondary zinc smelting and thermal wire reclamation were about one to three order magnitude higher than those of other sources, which suggests that these two sources be given priority in PCB source control. Finally, the atmospheric emission factors of PCBs from the thirteen industrial sources were summarized, and these data will be useful for developing an integrated emission inventory of PCBs.

  5. Kinetics of polychlorinated biphenyl partitioning to marine Chrysophyte Isochrysis galbana

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Fung-Chi, E-mail: ko@nmmba.gov.tw [National Dong Hwa University, Institute of Marine Biodiversity and Evolutionary Biology, Taiwan, ROC (China); National Museum of Marine Biology and Aquarium, Pingtung, Taiwan, ROC (China); Baker, Joel E. [The Center for Urban Waters, University of Washington, Tacoma, WA 98402 (United States); Tew, Kwee S. [National Dong Hwa University, Institute of Marine Biodiversity and Evolutionary Biology, Taiwan, ROC (China); National Museum of Marine Biology and Aquarium, Pingtung, Taiwan, ROC (China)

    2012-02-01

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

  6. Kinetics of polychlorinated biphenyl partitioning to marine Chrysophyte Isochrysis galbana.

    Science.gov (United States)

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

    2012-02-01

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

  7. Accumulation and efflux of polychlorinated biphenyls in Escherichia coli.

    Science.gov (United States)

    Geng, Shen; Fang, Jun; Turner, Kendrick B; Daunert, Sylvia; Wei, Yinan

    2012-06-01

    Polychlorinated biphenyls (PCBs) are environmental pollutants that have been associated with numerous adverse health effects in human and animals. Hydroxylated PCBs (HPCBs) are the product of the oxidative metabolism of PCBs. The presence of hydroxyl groups in HPCBs makes these compounds more hydrophilic than the parent PCBs. One of the best approaches to break down and remove these contaminants is bioremediation; an environmentally friendly process that uses microorganisms to degrade hazardous chemicals into non-toxic ones. In this study, we investigated the cellular accumulation and toxicity of selected PCBs and HPCBs in Gram-negative bacteria, using Escherichia coli as a model organism. We found that none of the five PCBs tested were toxic to E. coli, presumably due to their limited bioavailability. Nevertheless, different HPCBs tested showed different levels of toxicity. Furthermore, we demonstrated that the primary multidrug efflux system in E. coli, AcrAB-TolC, facilitated the efflux of HPCBs out of the cell. Since AcrAB-TolC is constitutively expressed in E. coli and is conserved in all sequenced Gram-negative bacterial genomes, our results suggest that the efflux activities of multidrug resistant pumps may affect the accumulation and degradation of PCBs in Gram-negative bacteria.

  8. Organochlorine pesticides and polychlorinated biphenyls in California sea lions

    International Nuclear Information System (INIS)

    Concentrations of polychlorinated biphenyls (PCBs), DDTs, chlordanes, HCHs, hexachlorobenzene (HCB), dieldrin, heptachlor epoxide, tris(4-chlorophenyl)methane (TCPMe), and tris(4-chlorophenyl)methanol (TCPMOH) were measured in the blubber of California sea lions (Zalophus californianus) collected in 2000. DDTs were the most predominant contaminants, followed by PCBs, chlordanes, TCPMe, HCHs, TCPMOH, dieldrin, and heptachlor epoxide. Concentrations of PCBs and DDTs varied from a few μg/g to several hundreds of μg/g on a lipid weight basis. Concentrations of DDTs have declined by an order of magnitude over the last three decades in California sea lions; nevertheless, the measured concentrations of PCBs and DDTs in California sea lions are still some of the highest values reported for marine mammals in recent years. Concentrations of organochlorines were highly correlated with one another. Concentrations of PCBs and DDTs in the blubber of gray whale, humpback whale, northern elephant seal, and harbor seal, and in the adipose fat of sea otter, were lower than the levels found in California sea lions, and were in the range of a few to several μg/g on a lipid weight basis

  9. The internal barriers of rotation for the 209 polychlorinated biphenyls.

    Science.gov (United States)

    Andersson, P L; Haglund, P; Tysklind, M

    1997-01-01

    The internal barrier of rotation (Erot) was calculated for all 209 polychlorinated biphenyls (PCBs) by using a semi-empirical method, viz. the Austin Model 1 (AMI) Hamiltonian. The difference in total energy between a forced planar state and an optimised twisted structure was defined as Erot. The Erot values were in the range of 8.33 to 483 kJ/mol, and were significantly influenced by the number of chlorine atoms in ortho position. An additional structural characteristic of the PCBs influencing Erot of ortho substituted congeners was substitution by chlorine atoms in vicinal meta positions, which is assumed to prevent outward bending of ortho substituents. This so-called buttressing effect contributed with 4 to 31 kJ/mol per added chlorine atom. In conclusion, the internal barrier of rotation, calculated for all 209 PCBs, provides an important structure dependent physico-chemical parameter for multivariate modelling of future quantitative structure-activity and structure-property relationships (QSARs/QSPRs). PMID:19005788

  10. Preconception maternal polychlorinated biphenyl concentrations and the secondary sex ratio

    International Nuclear Information System (INIS)

    The secondary sex ratio is the ratio of male to female live births and historically has ranged from 102 to 106 males to 100 females. Temporal declines have been reported in many countries prompting authors to hypothesize an environmental etiology. Blood specimens were obtained from 99 women aged 24-34 prior to attempting pregnancy and quantified for 76 polychlorinated biphenyl (PCB) congeners using dual column gas chromatography with electron capture detection. Women were prospectively followed until pregnancy or 12 cycles of trying. The odds of a male birth for three PCB groupings (total, estrogenic, anti-estrogenic) controlling for maternal characteristics were estimated using logistic regression. Among the 50 women with live births and PCB data, 26 female and 24 male infants were born (ratio 0.92). After adjusting for age and body mass index, odds of a male birth were elevated among women in the second (OR=1.29) and third (OR=1.48) tertiles of estrogenic PCBs; odds (OR=0.70) were reduced among women in the highest tertile of anti-estrogenic PCBs. All confidence intervals included one. The direction of the odds ratios in this preliminary study varied by PCB groupings, supporting the need to study specific PCB patterns when assessing environmental influences on the secondary sex ratio

  11. Detection of polychlorinated biphenyls in transformer oils in Vietnam by multiphoton ionization mass spectrometry using a far-ultraviolet femtosecond laser as an ionization source.

    Science.gov (United States)

    Vu, Thi Thuy Duong; Vu, Duong; Nghiem, Thi Ha Lien; Imasaka, Tomoko; Tang, Yuanyuan; Shibuta, Shinpei; Hamachi, Akifumi; Do, Quang Hoa; Imasaka, Totaro

    2016-03-01

    Polychlorinated biphenyls (PCBs) in transformer and food oils were measured using gas chromatography combined with multiphoton ionization mass spectroscopy. An ultrashort laser pulse emitting in the far-ultraviolet region was utilized for efficient ionization of the analytes. Numerous signal peaks were clearly observed for a standard sample mixture of PCBs when the third and fourth harmonic emissions (267 and 200nm) of a femtosecond Ti:sapphire laser (800nm) were employed. The signal intensities were found to be greater when measured at 200nm compared with those measured at 267nm, providing lower detection limits especially for highly chlorinated PCBs at shorter wavelengths. After simple pretreatment using disposable columns, PCB congeners were measured and found to be present in the transformer oils used in Vietnam. PMID:26717841

  12. Detection of polychlorinated biphenyls in transformer oils in Vietnam by multiphoton ionization mass spectrometry using a far-ultraviolet femtosecond laser as an ionization source.

    Science.gov (United States)

    Vu, Thi Thuy Duong; Vu, Duong; Nghiem, Thi Ha Lien; Imasaka, Tomoko; Tang, Yuanyuan; Shibuta, Shinpei; Hamachi, Akifumi; Do, Quang Hoa; Imasaka, Totaro

    2016-03-01

    Polychlorinated biphenyls (PCBs) in transformer and food oils were measured using gas chromatography combined with multiphoton ionization mass spectroscopy. An ultrashort laser pulse emitting in the far-ultraviolet region was utilized for efficient ionization of the analytes. Numerous signal peaks were clearly observed for a standard sample mixture of PCBs when the third and fourth harmonic emissions (267 and 200nm) of a femtosecond Ti:sapphire laser (800nm) were employed. The signal intensities were found to be greater when measured at 200nm compared with those measured at 267nm, providing lower detection limits especially for highly chlorinated PCBs at shorter wavelengths. After simple pretreatment using disposable columns, PCB congeners were measured and found to be present in the transformer oils used in Vietnam.

  13. Toxicological evaluation of chemical mixtures

    NARCIS (Netherlands)

    Feron, V.J.; Groten, J.P.

    2002-01-01

    This paper addresses major developments in the safety evaluation of chemical mixtures during the past 15 years, reviews today's state of the art of mixture toxicology, and discusses challenges ahead. Well-thought-out tailor-made mechanistic and empirical designs for studying the toxicity of mixtures

  14. Separating Underdetermined Convolutive Speech Mixtures

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Wang, DeLiang; Larsen, Jan;

    2006-01-01

    a method for underdetermined blind source separation of convolutive mixtures. The proposed framework is applicable for separation of instantaneous as well as convolutive speech mixtures. It is possible to iteratively extract each speech signal from the mixture by combining blind source separation...

  15. Source apportionment of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in ambient air of an industrial region in Turkey

    Science.gov (United States)

    Aydin, Yagmur Meltem; Kara, Melik; Dumanoglu, Yetkin; Odabasi, Mustafa; Elbir, Tolga

    2014-11-01

    Source apportionment is generally applied to a time series of data collected at a single site. However, in a complex airshed containing several different sources, it may be helpful to collect samples from multiple sites to ensure that some of them have low contributions from specific sources, thus the boundaries can be properly defined. Ambient air polycyclic aromatic hydrocarbon (PAH) and polychlorinated biphenyls (PCB) samples (n = 160) were collected at 40 sites during four seasons (summer, fall, winter, and spring) between July 2009 and April 2010 in the heavily industrialized Aliaga region in Turkey to investigate their spatial, seasonal variations and to identify possible PAH and PCB sources. The newest version of EPA PMF (V5.0) having the capability of handling multiple site data was used for source apportionment. Five PAH sources were identified as biomass and coal combustion, iron-steel production, unburned crude oil and petroleum products, and diesel and gasoline exhaust emissions with contributions of 40, 27, 27, 3, and 3%, respectively. The sources of PCBs were identified as iron-steel production (consisting of steel-making and ship breaking activities), coal and wood combustion, and evaporative emissions from technical PCB mixtures with contributions of 57, 31, and 12%, respectively.

  16. Formation of Polychlorinated Biphenyls on Secondary Copper Production Fly Ash: Mechanistic Aspects and Correlation to Other Persistent Organic Pollutants

    Science.gov (United States)

    Jiang, Xiaoxu; Liu, Guorui; Wang, Mei; Zheng, Minghui

    2015-09-01

    Emission of unintentionally formed polychlorinated biphenyls (PCBs) from industrial thermal processes is a global issue. Because the production and use of technical PCB mixtures has been banned, industrial thermal processes have become increasingly important sources of PCBs. Among these processes, secondary copper smelting is an important PCB source in China. In the present study, the potential for fly ash-mediated formation of PCBs in the secondary copper industry, and the mechanisms involved, were studied in laboratory thermochemical experiments. The total PCB concentrations were 37-70 times higher than the initial concentrations. Thermochemical reactions on the fly ash amplified the potential toxic equivalents of PCBs. The formation of PCBs over time and the effect of temperature were investigated. Based on analyses of PCB homologue profiles with different reaction conditions, a chlorination mechanism was proposed for forming PCBs in addition to a de novo synthesis mechanism. The chlorination pathway was supported by close correlations between each pair of adjacent homologue groups. Formation of PCBs and multiple persistent organic pollutants, including polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated naphthalenes, occurred during the tests, indicating that these compounds may share similar formation mechanisms.

  17. Uptake and Translocation of Lesser-Chlorinated Polychlorinated Biphenyls (PCBs) in Whole Hybrid Poplar Plants after Hydroponic Exposure

    Science.gov (United States)

    Liu, Jiyan; Schnoor, Jerald L.

    2009-01-01

    Mono-, di-, tri-, and tetra-chlorinated polychlorinated biphenyls (PCBs) are congeners with greater volatility which remain in air, soils and sediments requiring treatment. In this study, the fate of these PCBs was investigated within whole poplar plants (Populus deltoides x nigra, DN34) with application for a treatment system such as a confined disposal facility for dredged material. Whole hybrid poplars were exposed hydroponically to a mixture of five congeners, common in the environment, having one to four chlorine atoms per molecule. Results indicated that PCB 3, 15, 28, 52, and 77 were initially sorbed to the root systems. The Root Concentration Factor (RCF) of PCBs during the exposure was calculated and correlated with Kow. PCB congeners were taken up by the roots of hybrid poplar, and the translocation of PCBs to stems was inversely related to congener hydrophobicity (Log Kow). PCB 3 and 15 were translocated to the upper stem at small but significant rates. PCB 28 was translocated to the wood of the main stem but no farther; translocation from the roots was not detected for PCB 52 and 77. The distribution of PCBs within poplars was determined, and mass balances were completed to within 15% for each chemical except for PCB 3, the most volatile congener. This is the first report on the transport of PCBs through whole plants designed for use in treatment at disposal facilities. PMID:18793792

  18. Separation of gas mixtures

    International Nuclear Information System (INIS)

    Apparatus is described for the separation of a gaseous plasma mixture into components in some of which the original concentration of a specific ion has been greatly increased or decreased, comprising: a source for converting the gaseous mixture into a train of plasma packets; an open-ended vessel with a main section and at least one branch section, adapted to enclose along predetermined tracks the original plasma packets in the main section, and the separated plasma components in the branch sections; drive means for generating travelling magnetic waves along the predetermined tracks with the magnetic flux vector of the waves transverse to each of the tracks; and means for maintaining phase coherence between the plasma packets and the magnetic waves at a value needed for accelerating the components of the packets to different velocities and in such different directions that the plasma of each packet is divided into distinctly separate packets in some of which the original concentration of a specific ion has been greatly increased or decreased, and which plasma packets are collected from the branch sections of the vessels. (author)

  19. Mixture Based Outlier Filtration

    Directory of Open Access Journals (Sweden)

    P. Pecherková

    2006-01-01

    Full Text Available Success/failure of adaptive control algorithms – especially those designed using the Linear Quadratic Gaussian criterion – depends on the quality of the process data used for model identification. One of the most harmful types of process data corruptions are outliers, i.e. ‘wrong data’ lying far away from the range of real data. The presence of outliers in the data negatively affects an estimation of the dynamics of the system. This effect is magnified when the outliers are grouped into blocks. In this paper, we propose an algorithm for outlier detection and removal. It is based on modelling the corrupted data by a two-component probabilistic mixture. The first component of the mixture models uncorrupted process data, while the second models outliers. When the outlier component is detected to be active, a prediction from the uncorrupted data component is computed and used as a reconstruction of the observed data. The resulting reconstruction filter is compared to standard methods on simulated and real data. The filter exhibits excellent properties, especially in the case of blocks of outliers. 

  20. Polychlorinated biphenyls in Spanish adults: Determinants of serum concentrations

    International Nuclear Information System (INIS)

    Background: Polychlorinated biphenyls (PCBs) are persistent compounds that may pose an environmental hazard to humans, food being the main source of exposure for the general population. Objective: To measure the serum concentrations of the main PCBs in subjects from the general population in Spain, and to assess potential determinants of such concentrations. Methods: Serum was obtained from blood samples of 953 subjects aged 35-64 years, residents in five Spanish regions (three from the North and two from the South), randomly selected from the EPIC-Spain cohort. Blood collection took place during 1992-1996 and four PCB congeners (118, 138, 153 and 180) were determined by means of gas chromatography with electron-capture detection (GC-ECD). Results: The concentration of total PCBs was 459 ng/g lipids (or 3.1 μg/l); the corresponding figures for PCB 153 were 186 ng/g lipids and 1.25 μg/l. Men had higher values than women, PCB levels increased with age, and serum concentration of PCBs was higher in northern regions. Body mass index (BMI) was inversely related to PCB concentrations, and fish intake was the dietary factor showing the greatest association with serum PCBs. The pattern described was similar for each congener separately. Conclusions: We found concentrations similar to those reported in European countries where blood collection was carried during the same period. Regional differences within Spain are not fully explained by anthropometric or dietary factors. The inverse association with BMI suggests that in the mid-1990s there was still ongoing or recent exposure to PCBs in Spain.

  1. Dietary uptake of polychlorinated biphenyls (PCBs) by rainbow trout

    Science.gov (United States)

    Carline, Robert F.; Barry, Patrick M.; Ketola, H. George

    2004-01-01

    The presence of detectable levels of polychlorinated biphenyls (PCBs) in commercially produced fish feed has raised a concern about the degree of biomagnification of these contaminants in hatchery-reared trout. Our objectives were to (1) define the relationship between concentrations of PCBs in fish feed and in fish tissue and (2) estimate the relative contributions of feed and hatchery supply water to PCB concentrations in fish. We conducted a 6-month feeding trial with fingerling rainbow trout Oncorhynchus mykiss fed commercial diets with four concentrations of PCBs: a low-PCB diet (69 ng/g); a typical commercial diet (126 ng/g); and the typical diet spiked with PCBs at two levels (220 and 280 ng/g). The concentrations of PCBs in fillets after 1 month were commensurate with those in the feeds and remained relatively stable for the next 5 months; mean PCB concentrations in fillets ranged from 54 to 94 ng/g. Low levels of PCBs were detected in the hatchery supply water. We used the concentrations of PCBs in the feeds, absorption rates of PCBs, and two different rates of PCB depuration to estimate the potential uptake of PCBs from supply water. When we used a low depuration rate (half-life = 219 d), the computed body burdens of PCBs could be entirely attributed to the feeds. When a high depuration rate (half-life = 66 d) was used, some uptake of PCBs from the supply water was likely, but most of the total body burden originated from the feeds. We concluded that rainbow trout fed a diet with 126 ng/g PCBs would have a PCB concentration of about 60 ng/g in their fillets, which is high enough to warrant issuance of a consumption advisory (no more than one meal of fish per week) under a protocol adopted by some Great Lakes states.

  2. Immunotoxicity Monitoring in a Population Exposed to Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    Hajo Haase

    2016-03-01

    Full Text Available The relationship between polychlorinated biphenyl (PCB burden and several indicators of immune function was investigated as part of the HELPcB (Health Effects in High-Level Exposure to PCB program, offering bio-monitoring to workers, relatives, and neighbors exposed to PCBs by a German transformers and capacitors recycling company. The present retrospective observational study evaluates the correlation of plasma levels of total PCBs, five indicator congeners (28, 101, 138, 153, 180, and seven dioxin-like congeners (105, 114, 118, 156, 157, 167, 189 with several parameters of immune function. The cross-sectional study was performed immediately after the end of exposure (258 subjects, and one (218 subjects, and two (177 subjects years later. At the first time point, measurements showed significant positive correlation between congeners with low to medium chlorination and the relative proportion of CD19 positive B-cells among lymphocytes, as well as a negative correlation of PCB114 with serum IgM, and of PCB 28 with suppressor T-cell and NK-cell numbers. Congeners with a high degree of chlorination, in particular PCB157 and 189, were positively associated with expression of the activation marker CD25 on T-cells in the cohort of the second time point. No associations between PCB levels and IFN-y production by T-cells and killing by NK-cells were found. In conclusion, there were several effects on the cellular composition of adaptive immunity, affecting both T- and B-cells. However, the values were not generally outside the reference ranges for healthy adult individuals and did not indicate overt functional immunodeficiency, even in subjects with the uppermost PCB burden.

  3. Polychlorinated biphenyls in Spanish adults: Determinants of serum concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Agudo, Antonio, E-mail: a.agudo@iconcologia.net [Unit of Nutrition, Environment, and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology (ICO), IDIBELL, Av. Gran Via no 199-203, 08907 L' Hospitalet de Llobregat (Spain); Goni, Fernando [Laboratorio de Salud Publica de Guipuzcoa, 20013 San Sebastian (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Etxeandia, Arsenio [Laboratorio de Salud Publica de Vizcaya, 48010 Bilbao (Spain); Vives, Asuncion [Laboratorio Unificado Donostia, Hospital N. S. Aranzazu, 20014 San Sebastian (Spain); Millan, Esmeralda [Departamento de Quimica Aplicada, Universidad del Pais Vasco, Facultad de Quimica, 20080 San Sebastian (Spain); Lopez, Raul [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Amiano, Pilar [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Direccion de Salud de Guipuzcoa, 20013 San Sebastian (Spain); Ardanaz, Eva; Barricarte, Aurelio [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Instituto de Salud Publica de Navarra, 31003 Pamplona (Spain); Dolores Chirlaque, M. [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Consejeria de Sanidad, 3008 Murcia (Spain); Dorronsoro, Miren [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Direccion de Salud de Guipuzcoa, 20013 San Sebastian (Spain); Jakszyn, Paula [Unit of Nutrition, Environment, and Cancer, Cancer Epidemiology Research Program, Catalan Institute of Oncology (ICO), IDIBELL, Av. Gran Via no 199-203, 08907 L' Hospitalet de Llobregat (Spain); Larranaga, Nerea [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Direccion de Salud de Guipuzcoa, 20013 San Sebastian (Spain); Martinez, Carmen [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Escuela Andaluza de Salud Publica, 18080 Granada (Spain); Navarro, Carmen [CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Consejeria de Sanidad, 3008 Murcia (Spain); Rodriguez, Laudina [Consejeria de Salud y Servicios Sanitarios de Asturias, 33001 Oviedo (Spain); and others

    2009-07-15

    Background: Polychlorinated biphenyls (PCBs) are persistent compounds that may pose an environmental hazard to humans, food being the main source of exposure for the general population. Objective: To measure the serum concentrations of the main PCBs in subjects from the general population in Spain, and to assess potential determinants of such concentrations. Methods: Serum was obtained from blood samples of 953 subjects aged 35-64 years, residents in five Spanish regions (three from the North and two from the South), randomly selected from the EPIC-Spain cohort. Blood collection took place during 1992-1996 and four PCB congeners (118, 138, 153 and 180) were determined by means of gas chromatography with electron-capture detection (GC-ECD). Results: The concentration of total PCBs was 459 ng/g lipids (or 3.1 {mu}g/l); the corresponding figures for PCB 153 were 186 ng/g lipids and 1.25 {mu}g/l. Men had higher values than women, PCB levels increased with age, and serum concentration of PCBs was higher in northern regions. Body mass index (BMI) was inversely related to PCB concentrations, and fish intake was the dietary factor showing the greatest association with serum PCBs. The pattern described was similar for each congener separately. Conclusions: We found concentrations similar to those reported in European countries where blood collection was carried during the same period. Regional differences within Spain are not fully explained by anthropometric or dietary factors. The inverse association with BMI suggests that in the mid-1990s there was still ongoing or recent exposure to PCBs in Spain.

  4. Ecotoxicology of polychlorinated biphenyls in fish--a critical review.

    Science.gov (United States)

    Henry, T B

    2015-01-01

    Polychlorinated biphenyls (PCBs) are widespread persistent anthropogenic contaminants that can accumulate in tissues of fish. The toxicity of PCBs and their transformation products has been investigated for nearly 50 years, but there is a lack of consensus regarding the effects of these environmental contaminants on wild fish populations. The objective of this review is to critically examine these investigations and evaluate publicly available databases for evidence of effects of PCBs in wild fish. Biological activity of PCBs is limited to a small proportion of PCB congeners [e.g., dioxin-like PCBs (DL-PCBs)] and occurs at concentrations that are typically orders of magnitude higher than PCB levels detected in wild fish. Induction of biomarkers consistent with PCB exposure (e.g., induction of cytochrome P450 monooxygenase system) has been evaluated frequently and shown to be induced in fish from some environments, but there does not appear to be consistent reports of damage (i.e., biomarkers of effect) to biomolecules (i.e., oxidative injury) in these fish. Numerous investigations of endocrine system dysfunction or effects on other organ systems have been conducted in wild fish, but collectively there is no consistent evidence of PCB effects on these systems in wild fish. Early life stage toxicity of DL-PCBs does not appear to occur at concentrations reported in wild fish embryos, and results do not support an association between PCBs and decreased survival of early life stages of wild fish. Overall, there appears to be little evidence that PCBs have had any widespread effect on the health or survival of wild fish.

  5. Formation and stability of polychlorinated biphenyl Pickering emulsions

    Science.gov (United States)

    Roy-Perreault, Andréanne; Kueper, Bernard H.; Rawson, Jim

    2005-03-01

    An emulsion stabilized by colloidal suspensions of finely divided solids is known as a Pickering emulsion. The potential for polychlorinated biphenyls (PCBs) to form Pickering emulsions ex situ when in contact with powdered solids, such as clays and metal oxides, is investigated here. Bentonite, iron oxide and magnesium oxide dispersions proved to be robust Pickering emulsion stabilizers, whereas manganese oxide dispersions were not. Batch experiments revealed that emulsions can be formed using a moderately low energy input and can be stabilized with solid concentrations as low as 0.5 wt.%. For the base conditions (volumetric oil fraction ( ϕoil)=30 vol.%; solid concentration ( χ)=2 wt.%), the formed emulsions were indefinitely stable and the initial average droplet diameters varied from 80 to 258 μm, depending on the solid used in the colloidal dispersion. The average droplet size varied at early time, but for most conditions stabilized to a steady-state value 1 week after preparation. The effect of Ostwald ripening was limited. At greater than 0.5 wt.% concentration, the efficiency of the solid dispersion as a stabilizer was dependant on the volumetric oil fraction but not on the solid concentration. Generally, systems with volumetric oil fractions outside of the 20-70 vol.% range were unstable. The emulsions' droplet stability, average droplet size and size distribution were observed to vary as a function of the amount of energy provided to the system, the volumetric oil fraction, and the concentration of the solid in the aqueous dispersion. It is hypothesized that drilling through fractured rock in the immediate vicinity of dense, non-aqueous phase liquid (DNAPL) PCBs may provide both the energy and solid material necessary to form Pickering emulsions.

  6. Early decrease in retinoid levels in mice after exposure to low doses of polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Brouwer, A.; van den Berg, K.J.

    1983-01-01

    This paper investigates the influence of PCBs on natural retinoid levels of mice. In an initial experiment c57BL/Rij mice, a responder type with respect to aryl hydrocarbon hydroxylase (AHH) induction, were exposed to a low dose of Aroclor 1254 or 3,4,3',4' tetrachlorobiphenyl (TCB). Natural retinoids of livers and blood sera were analysed by high pressure liquid chromatography (HPLC) on a weekly basis. After four to five weeks, a significant reduction in liver retinol and an additional reduction in serum retinol was observed. At this dose level, none of the toxicity parameters, e.g., reduction in body and thymus weights, increased liver weight and AHH induction, were significantly influenced.

  7. The variability of polychlorinated biphenyls levels in urban soils from five European cities.

    Science.gov (United States)

    Cachada, A; Lopes, L V; Hursthouse, A S; Biasioli, M; Grcman, H; Otabbong, E; Davidson, C M; Duarte, A C

    2009-02-01

    The concentration of PCBs in topsoils from five European cities was assessed and the highest levels were found in Glasgow (Scotland), followed by Torino (Italy), Aveiro (Portugal), Ljubljana (Slovenia) and Uppsala (Sweden). All cities showed the presence of local sources in addition to diffuse contamination from global atmospheric transport. The association of general soil parameters with PCBs in Glasgow and with heavier congeners in Torino and Ljubljana indicates that retention of these compounds is occurring. The profiles obtained resemble Aroclor 1254 and 1260, which are important local sources. Nevertheless, differences in PCB profiles were observed among cities, due to the combined effects of the age of the contamination (which determines the time available for volatilisation and degradation), different sources of PCBs and differences in climate (which influence volatilisation and deposition).

  8. 2,2,6,6-Tetrakis(biphenyl-2-yl-4,4,8,8-tetramethylcyclotetrasiloxane

    Directory of Open Access Journals (Sweden)

    Erik P. A. Couzijn

    2009-09-01

    Full Text Available The title compound, [–Si(C12H92OSi(CH32O–]2, was obtained unintentionally as the product of an attempted crystallization of caesium bis(biphenyl-2,2′-diylfluorosilicate from dimethylformamide. In the crystal, the molecule is located on an inversion center and the siloxane ring adopts a twist-chair conformation with the two dimethyl-substituted Si atoms lying 0.7081 (5 Å out of the plane defined by the two bis(biphenyl-2-yl-substituted Si atoms and the four O atoms. In each Si(C12H92 unit, the orientation of one terminal phenyl ring relative to the phenylene ring of the other biphenyl moiety suggests a parallel displaced π–π stacking interaction [centroid distance = 4.2377 (11 Å and dihedral angle = 15.40 (9°].

  9. Molecular Descriptors Family on Structure Activity Relationships 6. Octanol-Water Partition Coefficient of Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    Lorentz JÄNTSCHI

    2006-01-01

    Full Text Available Octanol-water partition coefficient of two hundred and six polychlorinated biphenyls was model by the use of an original method based on complex information obtained from compounds structure. The regression analysis shows that best results are obtained in four-varied model (r2 = 0.9168. The prediction ability of the model was studied through leave-one-out analysis (r2cv(loo = 0.9093 and in training and test sets analysis. Modeling the octanol-water partition coefficient of polychlorinated biphenyls by integration of complex structural information provide a stable and performing four-varied model, allowing us to make remarks about relationship between structure of polychlorinated biphenyls and associated octanol-water partition coefficients.

  10. Spermaturia and serum hormone concentrations at the age of puberty in boys prenatally exposed to polychlorinated biphenyls

    DEFF Research Database (Denmark)

    Mol, Nanette M; Sørensen, Nicolina; Weihe, Pal;

    2002-01-01

    To determine whether prenatal exposure to polychlorinated biphenyls (PCBs) with possible hormone-disrupting effects is capable of affecting sexual differentiation in boys at the age of puberty.......To determine whether prenatal exposure to polychlorinated biphenyls (PCBs) with possible hormone-disrupting effects is capable of affecting sexual differentiation in boys at the age of puberty....

  11. Toxicological evaluation of chemical mixtures.

    Science.gov (United States)

    Feron, V J; Groten, J P

    2002-06-01

    This paper addresses major developments in the safety evaluation of chemical mixtures during the past 15 years, reviews today's state of the art of mixture toxicology, and discusses challenges ahead. Well-thought-out tailor-made mechanistic and empirical designs for studying the toxicity of mixtures have gradually substituted trial-and-error approaches, improving the insight into the testability of joint action and interaction of constituents of mixtures. The acquired knowledge has successfully been used to evaluate the safety of combined exposures and complex mixtures such as, for example, the atmosphere at hazardous waste sites, drinking water disinfection by-products, natural flavouring complexes, and the combined intake of food additives. To consolidate the scientific foundation of mixture toxicology, studies are in progress to revisit the biological concepts and mathematics underlying formulas for low-dose extrapolation and risk assessment of chemical mixtures. Conspicuous developments include the production of new computer programs applicable to mixture research (CombiTool, BioMol, Reaction Network Modelling), the application of functional genomics and proteomics to mixture studies, the use of nano-optochemical sensors for in vivo imaging of physiological processes in cells, and the application of optical sensor micro- and nano-arrays for complex sample analysis. Clearly, the input of theoretical biologists, biomathematicians and bioengineers in mixture toxicology is essential for the development of this challenging branch of toxicology into a scientific subdiscipline of full value. PMID:11983277

  12. Comparison of an enzyme-linked immunosorbent assay (ELISA) to gas chromatography (GC) - measurement of polychlorinated biphenyls (PCBs) in selected US fish extracts

    Science.gov (United States)

    Zajicek, J.L.; Tillitt, D.E.; Schwartz, T.R.; Schmitt, C.J.; Harrison, R.O.

    2000-01-01

    The analysis of PCBs in fish tissues by immunoassay methods was evaluated using fish collected from a US monitoring program, the National Contaminant Biomonitoring Program of the US Department of Interior, Fish and Wildlife Service. Selected composite whole fish samples, which represented widely varying concentrations and sources of PCBs, were extracted and subjected to congener PCB analysis by gas chromatography (GC) and total PCB analysis using an ELISA (ePCBs) calibrated against technical Aroclor 1248. PCB congener patterns in these fishes were different from the patterns found in commercial Aroclors or their combinations as demonstrated by principal component analysis of normalized GC congener data. The sum of the PCB congeners measured by GC (total-PCBs) ranged from 37 to 4600 ng/g (wet weight). Concentrations of PCBs as determined by the ELISA method were positively correlated with total-PCBs and the ePCBs/total-PCBs ratios for individual samples ranged from 1 to 6. Ratios of ePCBs/total-PCBs for dilutions of Aroclors 1242, 1254, and 1260 and for matrix spikes range from 0.6 for 1242 to 2.5 for 1254 and 1260. These results suggest that higher chlorinated PCB congeners have higher affinity for the anti-PCB antibodies. Partial least squares with latent variable analysis of GC and ELISA data of selected Aroclors and fish samples also support the conclusion that ELISA derived PCB concentrations are dependent on the degree on chlorination.

  13. Long-time measurements of polychlorinated dibenzodioxins (PCDD), dibenzofurans (PCDF) and biphenyls (PCB) in deposition

    International Nuclear Information System (INIS)

    Dioxins, furans and polychlorinated biphenyls from one and the same sample were first separated by chromatography, then determined by mass spectroscopy. Sampling was in accordance with VDI method No. 2119, sheet 2, for the measurement of particulate precipitations. The annual means of PCDD/PCDF deposition ranged from 10 to 83 pg TE/(m2.d). The annual means of the deposition of polychlorinated biphenyls (tri and decachlorobiphenyls combined) varied between 23 and 257 ng/(m2.d). The annual mean for coplanar PCBs No. 77, 126 and 169 was less than 1 ng/(m2.d). (orig./DG)

  14. Synthesis and Characterization of Nonsymmetric Liquid Crystal Dimer Containing Biphenyl and Azobenzene Moiety

    Directory of Open Access Journals (Sweden)

    S. Sandy Subala

    2013-01-01

    Full Text Available Calamitic liquid crystalline dimer containing azobenzene moiety and a decyloxy biphenyl linked by flexible spacers {4-[7-(4′-decyloxy-biphenyl-4-yloxy-alkyloxy]-phenyl}-(4-decyl-phenyl-diazene has been synthesized and characterized by spectroscopic methods. The transition temperatures and phase behaviours were studied by Differential Scanning Calorimeter (DSC and Polarizing Optical Microscope (POM. The synthesized compounds exhibited enantiotropic liquid crystal phase with higher spacer display nematic and smectic C phases while lower spacer shows nematic and smectic A phases.

  15. Bacterial degradation of polychlorinted biphenyls in sludge from an industrial sewer lagoon

    Science.gov (United States)

    Kim, W. S.; Takacs, A. M.; Kuivinen, D. E.

    1983-01-01

    A laboratory experiment was conducted to determine if polychlorinated biphenyls (PCB's) found in an industrial sewer sludge can be effectively degraded by mutant bacteria. The aerated sludge was inoculated daily with mutant bacteria in order to augment the existing bacteria with bacteria that were considered to be capable of degrading PCB's. The pH, nitrogen, and phosphorus levels were monitored daily to maintain an optimum growing medium for the bacteria. A gas chromatographic method was used to determine the PCB concentrations of the sludge initially and also throughout the experiment. Results and discussion of the bacterial treatment of polychlorinated biphenyls are presented.

  16. Degree of Contamination and Sources of Polychlorinated Biphenyls in Meandering Road Creek and Woods Inlet of Lake Worth, Fort Worth, Texas, 2004 and 2006-07

    Science.gov (United States)

    Braun, Christopher L.; Wilson, Jennifer T.; Van Metre, Peter C.

    2008-01-01

    Lake Worth is a reservoir on the West Fork Trinity River on the western edge of Fort Worth, Texas. Air Force Plant 4 (AFP4) is on the eastern shore of Woods Inlet, an arm of Lake Worth that extends south from the main body of the lake. Two previous reports documented ele-vated polychlorinated biphenyl (PCB) concentrations in surficial sediment in Woods Inlet relative to those in surficial sediment in other parts of Lake Worth. This report presents the results of another USGS study, done in cooperation with the U.S. Air Force, to indicate the degree of PCB contamination of Meandering Road Creek and Woods Inlet and to identify possible sources of PCBs in Meandering Road Creek and Woods Inlet on the basis of suspended, streambed, and lake-bottom sediment samples collected there in 2004 and 2006-07. About 40 to 80 percent of total PCB concentrations (depending on how total PCB concentration is computed) in suspended sediment exceed the threshold effect concentration, a concentration below which adverse effects to benthic biota rarely occur. About 20 percent of total PCB concentrations (computed as sum of three Aroclors) in suspended sediment exceed the probable effect concentration, a concentration above which adverse effects to benthic biota are expected to occur frequently. About 20 to 30 percent of total PCB concentrations in streambed sediment exceed the threshold effect concentration; and about 6 to 20 percent of total PCB concentrations in lake-bottom (Woods Inlet) sediment exceed the threshold effect concentration. No streambed or lake-bottom sediment concentrations exceed the probable effect concentration. The sources of PCBs to Meandering Road Creek and Woods Inlet were investigated by comparing the relative distributions of PCB congeners of suspended sediment to those of streambed and lake-bottom sediment. The sources of PCBs were identified using graphical analysis of normalized concentrations (congener ratios) of 11 congeners. For graphical analysis, the

  17. Plasma polychlorinated biphenyl concentrations and immune function in postmenopausal women

    International Nuclear Information System (INIS)

    Background: Polychlorinated biphenyl (PCB) exposure has been associated with non-Hodgkin lymphoma in several studies, and the immune system is a potential mediator. Objectives: We analyzed associations of plasma PCBs with immune function measures. We hypothesized that higher plasma PCB concentrations are associated with lower immune function cross-sectionally, and that increases in PCB concentrations over a one year period are associated with decreases in immune function. Methods: Plasma PCB concentrations and immune function [natural killer (NK) cell cytotoxicity and PHA-induced T-lymphocyte proliferation (PHA-TLP)] were measured at baseline and one year in 109 postmenopausal overweight women participating in an exercise intervention study in the Seattle, Washington (USA) area. Mixed models, with adjustment for body mass index and other potential confounders, were used to estimate associations of PCBs with immune function cross-sectionally and longitudinally. Results: Associations of PCBs with immune function measures differed across groups of PCBs (e.g., medium- and high-chlorinated and dioxin-like [mono-ortho-substituted]) and by the time frame for the comparison (cross-sectional vs. longitudinal). Higher concentrations of medium- and high-chlorinated PCBs were associated with higher PHA-TLP cross-sectionally but not longitudinally. The mean decrease in 0.5 µg/mL PHA-TLP/50.0 pmol/g-lipid increase in dioxin-like PCBs over one year was 51.6 (95% confidence interval 2.7, 100.5; P=0.039). There was no association between plasma PCBs and NK cytotoxicity. Conclusions: These results do not provide strong evidence of impaired cellular immunity from PCB exposure. Larger longitudinal studies with greater variability in PCB exposures are needed to further examine temporal associations of PCBs with immune function. - Highlights: • Plasma PCBs and immune function were measured in 109 women at baseline and one year. • Immune measures included T lymphocyte proliferation

  18. Foetal uptake of coplanar polychlorinated biphenyl (PCB) congeners in mice

    International Nuclear Information System (INIS)

    Earlier studies have shown that the Ah-receptor binding polychlorinated biphenyl (PCB) congener 3,3',4,4'-tetrachlorobiphenyl (IUPAC number CB-77) accumulated as hydroxy and methylsulphone metabolites in late gestational mice foetuses. In the present paper the foetal accumulation potential in mice of other dioxin-like PCB congeners was studied: 3,3'4,4',4-pentachlorobiphenyl, 3,3'4,4'5,5'-hexachlorobiphenyl and 2,3,3',4,4'-pentachlorobiphenyl (IUPAC numbers CB-126, CB-169, CB-105, to some extent dioxin-like) were compared to results of CB-77 (all congeners 14C-labelled and in equimolar doses (2.0 μmol/kg body wt.)). CB-77 resulted in the comparatively strongest foetal 14C-accumulation, when measured in plasma or whole body homogenate four days after administration (day 17 of pregnancy); the plasma 14C-values (calculated as pmol/g wet wt.) were 760, 130, 60 and 40 for CB-77, -126, 105 and -169, respectively, and the CB-77 derived radioactivity in the foetal compartment was 3.6% of administered dose (i.e. a considerable portion of the remaining maternal body radioactivity). Thin-layer chromatography (TLC) results, suggesting extensive CB-77 metabolism and foetal metabolite uptake, support earlier findings. The effects of CB-77 and CB-169 on foetal 7-ethoxyresorufin-O-deethylase (EROD) activities (day 17 of gestation; two days after 5 mg/kg body wt. dose (14.0-17.0 μmol/kg body wt.)) was about 20 times lower than of CB-126. In the dam, high radioactivity levels were observed int he liver and fat (highest concentrations found in CB-126 and CB-105, respectively). Strain comparison - foetal 14C-uptake (four days after administration of CB-77) in C57BL mice was almost five times higher than in NMRI - may be correlated to earlier observed differences in EROD activities between these strains. The present results indicate that congener and strain differences exist regarding both foetal and maternal distribution patterns of coplanar PCB congeners and point out the

  19. Plasma polychlorinated biphenyl concentrations and immune function in postmenopausal women

    Energy Technology Data Exchange (ETDEWEB)

    Spector, June T., E-mail: spectj@uw.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt Way NE, Seattle, WA 98105 (United States); Department of Medicine, School of Medicine, University of Washington, Seattle, WA (United States); De Roos, Anneclaire J., E-mail: ajd335@drexel.edu [Epidemiology Program, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, P.O. Box 19024, Seattle, WA 98109 (United States); Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA (United States); Ulrich, Cornelia M., E-mail: neli.ulrich@nct-heidelberg.de [Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA (United States); Cancer Prevention Program, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, P.O. Box 19024, Seattle, WA 98109 (United States); National Center for Tumor Diseases and German Cancer Research Center, Heidelberg (Germany); Sheppard, Lianne, E-mail: sheppard@uw.edu [Department of Environmental and Occupational Health Sciences, School of Public Health, University of Washington, 4225 Roosevelt Way NE, Seattle, WA 98105 (United States); Department of Biostatistics, School of Public Health, University of Washington, Seattle, WA (United States); Sjoedin, Andreas, E-mail: asjodin@cdc.gov [National Center for Environmental Health, CDC, 4770 Buford Highway NE, Atlanta, GA 30341 (United States); Wener, Mark H., E-mail: wener@u.washington.edu [Department of Medicine, School of Medicine, University of Washington, Seattle, WA (United States); Wood, Brent, E-mail: woodbl@u.washington.edu [Department of Medicine, School of Medicine, University of Washington, Seattle, WA (United States); and others

    2014-05-01

    Background: Polychlorinated biphenyl (PCB) exposure has been associated with non-Hodgkin lymphoma in several studies, and the immune system is a potential mediator. Objectives: We analyzed associations of plasma PCBs with immune function measures. We hypothesized that higher plasma PCB concentrations are associated with lower immune function cross-sectionally, and that increases in PCB concentrations over a one year period are associated with decreases in immune function. Methods: Plasma PCB concentrations and immune function [natural killer (NK) cell cytotoxicity and PHA-induced T-lymphocyte proliferation (PHA-TLP)] were measured at baseline and one year in 109 postmenopausal overweight women participating in an exercise intervention study in the Seattle, Washington (USA) area. Mixed models, with adjustment for body mass index and other potential confounders, were used to estimate associations of PCBs with immune function cross-sectionally and longitudinally. Results: Associations of PCBs with immune function measures differed across groups of PCBs (e.g., medium- and high-chlorinated and dioxin-like [mono-ortho-substituted]) and by the time frame for the comparison (cross-sectional vs. longitudinal). Higher concentrations of medium- and high-chlorinated PCBs were associated with higher PHA-TLP cross-sectionally but not longitudinally. The mean decrease in 0.5 µg/mL PHA-TLP/50.0 pmol/g-lipid increase in dioxin-like PCBs over one year was 51.6 (95% confidence interval 2.7, 100.5; P=0.039). There was no association between plasma PCBs and NK cytotoxicity. Conclusions: These results do not provide strong evidence of impaired cellular immunity from PCB exposure. Larger longitudinal studies with greater variability in PCB exposures are needed to further examine temporal associations of PCBs with immune function. - Highlights: • Plasma PCBs and immune function were measured in 109 women at baseline and one year. • Immune measures included T lymphocyte proliferation

  20. Intake of polychlorinated biphenyls (PCB) from the Finnish diet

    International Nuclear Information System (INIS)

    Concentrations of seven single PCB indicator congeners were measured in 99 food samples. These concentrations were converted into a total PCB content and used for estimating total PCB intake among Finns. The average intake from food is 15 μg/day or 0,25 μ/kg body weight per day, which showed no change during the late 1980s. Approximately half of the intake comes from fish. The composition of the PCB mixture varies a lot in different sample types, which emphasizes the importance of single compound determination. (orig.)

  1. Genomic characterization of three unique Dehalococcoides that respire on persistent polychlorinated biphenyls

    OpenAIRE

    Wang, Shanquan; Chng, Kern Rei; Wilm, Andreas; Zhao, Siyan; Yang, Kun-Lin; Nagarajan, Niranjan; HE, Jianzhong

    2014-01-01

    Polychlorinated biphenyls (PCBs) as persistent organic pollutants are widespread in the sediments of lakes, rivers, and harbors. Although the PCB detoxification through microbial reductive dechlorination has been extensively studied for more than 20 y, the difficulty in cultivating PCB dechlorinators in pure culture impedes further characterization, optimization, and application in in situ bioremediation. By combining traditional culture techniques with next-generation sequencing technology, ...

  2. Commentary on Polychlorinated Biphenyls (PCBs), Toxins, and Neuropsychological Deficits: Good Science is the Antidote

    Science.gov (United States)

    Hebben, Nancy

    2004-01-01

    The seven cohort studies of the relation between prenatal and postnatal exposure to polychlorinated biphenyls (PCBs) to cognitive, neuropsychological and behavioral development have suggested that exposure to PCBs can cause persistent changes in cognitive functioning. D.V. Cicchetti, A.S. Kaufman, and S.S. Sparrow (this issue) apply six scientific…

  3. A method for the chemical modification of polychlorinated biphenyls for improved affinity towards noble metal surfaces

    DEFF Research Database (Denmark)

    2015-01-01

    The present application discloses a method for the modification and analysis of a field sample suspected of containing contaminant(s) like polychlorinated biphenyls (PCBs). The invention also relates to a corresponding kit for the modification of samples suspected of containing such contaminant(s)....

  4. Polychlorinated Biphenyl Exposure and Glucose Metabolism in 9-Year-Old Danish Children

    DEFF Research Database (Denmark)

    Jensen, Tina K.; Timmermann, Amalie G.; Rossing, Laura I.;

    2014-01-01

    Context: Human exposure to polychlorinated biphenyls (PCBs) has been associated to type 2 diabetes in adults. Objectives: To determine whether concurrent serum PCB concentration was associated with markers of glucose metabolism in healthy children. Design: Cross-sectional study. Settings and part...

  5. Contamination of free-range chicken eggs with dioxins and dioxin-like polychlorinated biphenyls

    NARCIS (Netherlands)

    Schoeters, G.; Hoogenboom, L.A.P.

    2006-01-01

    Dioxins and dioxin-like (DL) polychlorinated biphenyls (PCB) are persistent organic pollutants that enter the body mainly by food intake. A small margin exists between current exposure levels in the human population and the levels causing biological effects. Therefore, stringent control of concentra

  6. New Biochemical Pathway for Biphenyl Degradation in Plants: Structural, Mechanistic and Biotechnological Aspects

    Energy Technology Data Exchange (ETDEWEB)

    Pacios, L. F.; Campos, V. M.; Merino, I.; Gomez, L.

    2009-07-01

    Polychlorinated biphenyls (PVBs) and other structurally-related xenobiotics are amongst the most relevant organic pollutants known today. while some bacterial species can metabolize PCBs, with varying efficiency, no catabolic pathways have yet been described in plants. This is so despite the great potential of (at least some) plant species for soil and groundwater decontamination, a technology known as phyto remediation. (Author)

  7. Immunologic effects of background exposure to polychlorinated biphenyls and dioxins in Dutch preschool children

    NARCIS (Netherlands)

    Weisglas-Kuperus, N; Patandin, S; Berbers, GAM; Sas, TCJ; Mulder, PGH; Sauer, PJJ; Hooijkaas, H

    2000-01-01

    Prenatal exposure to polychlorinated biphenyls (PCBs) and dioxins is associated with changes in the T-cell lymphocyte population in healthy Dutch infants. We investigated whether these changes persist into later childhood and whether background exposure to PCBs and dioxins is associated with the pre

  8. Biphenyl Phytoalexin in Sorbus pohuashanensis Suspension Cell Induced by Yeast Extract

    Directory of Open Access Journals (Sweden)

    Liangyun Zhou

    2016-09-01

    Full Text Available Biphenyls are unique phytoalexins de novo synthesized in plants in response to pathogen attack. These compounds are found in Maloideae, a subfamily of the Rosaceae. The anti-microbial activities of biphenyls have been reported in a number of studies and they appear to represent an important defense strategy against pathogens common in the Maloideae, such as species in Malus, Pyrus, Sorbus, and Chaenomeles. Here, cell suspension cultures of Sorbus pohuashanensis were established to study biphenyl phytoalexins formation after yeast extract (YE treatment. An ultra-performance liquid chromatography (UPLC method coupled with quadrupole time of flight mass spectrometry (Q-TOF-MS LC−MS/MS was applied to determine the time course of these biphenyl biomarkers accumulation in YE-treated S. pohuashanensis suspension cells. The results of quantitative analyses show the content of Noraucuparin, 2′-Hydroxyaucuparin, and their glycosides initially increased, then decreased over time. The Noraucuparin content reached its highest (225.76 μg·g−1 at 18 h after treatment, 6 hours earlier than that of Noraucuparin 5-O-β-d-glucopyranoside. The content of 2′-Hydroxyaucuparin reached its highest (422.75 μg·g−1 at 30 h after treatment, also earlier than that of its glycoside. The understanding of phytoalexin metabolism in this study may provide a basis for improving Maloideae resistance to pathogens.

  9. Polychlorinated biphenyls-induced alterations of thyroid hormone homeostasis and brain development in the rat.

    NARCIS (Netherlands)

    Morse, D.C.

    1995-01-01

    IntroductionThe work described in this thesis was undertaken to gain insight in the processes involved in the developmental neurotoxicity of polychlorinated biphenyls. It has been previously hypothesized that the alteration of thyroid hormone status by PCBs may be in part responsibl

  10. Modelling the impact of room temperature on concentrations of polychlorinated biphenyls (PCBs) in indoor air

    DEFF Research Database (Denmark)

    Lyng, Nadja; Clausen, Per Axel; Lundsgaard, Claus;

    2016-01-01

    Buildings contaminated with polychlorinated biphenyls (PCBs) are a health concern for the building occupants. Inhalation exposure is linked to indoor air concentrations of PCBs, which are known to be affected by indoor temperatures. In this study, a highly PCB contaminated room was heated to six ...

  11. Effects of sedimentary soot-like materials on bioaccumulation and sorption of polychlorinated biphenyls

    NARCIS (Netherlands)

    Jonker, M.T.O.; Hoenderboom, A.M.; Koelmans, A.A.

    2004-01-01

    Bioaccumulation of hydrophobic organic chemicals from sediments containing soot or sootlike materials has been hypothesized to be limited by strong sorption of the chemicals to the soot matrixes. To test this hypothesis, we quantified bioaccumulation of 11 polychlorinated biphenyls (PCBs) into the a

  12. An efficient synthesis, X-ray and spectral characterization of biphenyl derivatives

    Indian Academy of Sciences (India)

    Ravindra R Kamble; Dharesh B Biradar; Gangadhar Y Meti; Tasneem Taj; Tegginamath Gireesh; Imthiyaz Ahmed M Khazi; Sundar T Vaidyanathan; Raju Mohandoss; Balasubramanian Sridhar; Viraraghav Parthasarathi

    2011-07-01

    Derivatives of 1,3-thiazolidin-2,4-dione appended to biphenyl ring viz., 7-9, 16-18 were prepared. The newly synthesized compounds were confirmed by IR, NMR (1H and 13C) MS and elemental analyses. Single crystal X-ray diffraction study was carried out for one of the final compounds 9.

  13. Library of biphenyl privileged substructures using a safety-catch linker approach

    DEFF Research Database (Denmark)

    Severinsen, Rune; Bourne, Gregory T; Tran, Tran T;

    2008-01-01

    A biphenyl privileged structure library containing three attachment points were synthesized using a catechol-based safety-catch linker strategy. The method requires the attachment of a bromo-acid to the linker, followed by a Pd-catalyzed Suzuki cross-coupling reaction. Further derivatization...

  14. Assessment of polychlorinated biphenyls and organochlorine pesticides in water samples from the Yamuna River

    OpenAIRE

    Bhupander Kumar; Satish Kumar Singh; Meenu Mishra; Sanjay Kumar; Chandra Shekhar Sharma

    2012-01-01

    Polychlorinated biphenyls (PCBs), hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) are toxic, persistent and bioaccumulative long-range atmospheric transport pollutants. These are transported worldwide affecting remote regions far from their original sources, and can transfer into food webs with a wide range of acute and chronic health effects. India ratified the Stockholm Convention with the intention of reducing and eliminating persistent organic pollutants (POPs), and ...

  15. Polychlorinated biphenyls in adipose tissue, liver, and brain from nine stillborns of varying gestational ages

    NARCIS (Netherlands)

    Huisman, M; Muskiet, FAJ; Van Der Paauw, CG; Essed, CE; Boersma, ER

    1998-01-01

    We analyzed polychlorinated biphenyls (PCBs) in s.c. adipose tissue, liver, and brain of nine fetuses who died in utero. Their median (range) gestational ages and birth weights were 34 (17-40) wk and 2050 (162-3225) g. Three fetuses were small for gestational age. The levels of PCB congener nos. 118

  16. Evaporating Drops of Alkane Mixtures

    CERN Document Server

    Gu'ena, G; Poulard, C; Cazabat, Anne-Marie; Gu\\'{e}na, Geoffroy; Poulard, Christophe

    2005-01-01

    Alkane mixtures are model systems where the influence of surface tension gradients during the spreading and the evaporation of wetting drops can be easily studied. The surface tension gradients are mainly induced by concentration gradients, mass diffusion being a stabilising process. Depending on the relative concentration of the mixture, a rich pattern of behaviours is obtained.

  17. Easy and flexible mixture distributions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; Mabit, Stefan L.

    2013-01-01

    We propose a method to generate flexible mixture distributions that are useful for estimating models such as the mixed logit model using simulation. The method is easy to implement, yet it can approximate essentially any mixture distribution. We test it with good results in a simulation study...

  18. Effects of defined mixtures of persistent organic pollutants (POPs) on multiple cellular responses in the human hepatocarcinoma cell line, HepG2, using high content analysis screening.

    Science.gov (United States)

    Wilson, Jodie; Berntsen, Hanne Friis; Zimmer, Karin Elisabeth; Frizzell, Caroline; Verhaegen, Steven; Ropstad, Erik; Connolly, Lisa

    2016-03-01

    Persistent organic pollutants (POPs) are toxic substances, highly resistant to environmental degradation, which can bio-accumulate and have long-range atmospheric transport potential. Most studies focus on single compound effects, however as humans are exposed to several POPs simultaneously, investigating exposure effects of real life POP mixtures on human health is necessary. A defined mixture of POPs was used, where the compound concentration reflected its contribution to the levels seen in Scandinavian human serum (total mix). Several sub mixtures representing different classes of POPs were also constructed. The perfluorinated (PFC) mixture contained six perfluorinated compounds, brominated (Br) mixture contained seven brominated compounds, chlorinated (Cl) mixture contained polychlorinated biphenyls and also p,p'-dichlorodiphenyldichloroethylene, hexachlorobenzene, three chlordanes, three hexachlorocyclohexanes and dieldrin. Human hepatocarcinoma (HepG2) cells were used for 2h and 48h exposures to the seven mixtures and analysis on a CellInsight™ NXT High Content Screening platform. Multiple cytotoxic endpoints were investigated: cell number, nuclear intensity and area, mitochondrial mass and membrane potential (MMP) and reactive oxygen species (ROS). Both the Br and Cl mixtures induced ROS production but did not lead to apoptosis. The PFC mixture induced ROS production and likely induced cell apoptosis accompanied by the dissipation of MMP. Synergistic effects were evident for ROS induction when cells were exposed to the PFC+Br mixture in comparison to the effects of the individual mixtures. No significant effects were detected in the Br+Cl, PFC+Cl or total mixtures, which contain the same concentrations of chlorinated compounds as the Cl mixture plus additional compounds; highlighting the need for further exploration of POP mixtures in risk assessment. PMID:26772051

  19. Mixtures of truncated basis functions

    DEFF Research Database (Denmark)

    Langseth, Helge; Nielsen, Thomas Dyhre; Rumí, Rafael;

    2012-01-01

    In this paper we propose a framework, called mixtures of truncated basis functions (MoTBFs), for representing general hybrid Bayesian networks. The proposed framework generalizes both the mixture of truncated exponentials (MTEs) framework and the mixture of polynomials (MoPs) framework. Similar...... for efficiently approximating an arbitrary density function using the MoTBF framework. The transla- tion method is more flexible than existing MTE or MoP-based methods, and it supports an online/anytime tradeoff between the accuracy and the complexity of the approxima- tion. Experimental results show...

  20. Performance of asphalt rubber mixtures

    OpenAIRE

    Thives, Liseane Padilha; Trichês, Glicério; Pereira, Paulo A. A.; Pais, Jorge C.

    2010-01-01

    Asphalt rubber mixtures are one of the most promising techniques to extend the service life of asphalt pavement overlays. Asphalt rubber binder is composed of crumb rubber from reclaimed tires and conventional asphalt. The asphalt rubber binder can be obtained through wet process in two different systems: terminal blending (produced at industrial plants) and continuous blending (produced in asphalt plants). This study presents a laboratory evaluation of asphalt rubber mixtures produced with d...

  1. Optimal Parameters Multicomponent Mixtures Extruding

    Directory of Open Access Journals (Sweden)

    Ramil F. Sagitov

    2013-01-01

    Full Text Available Experimental research of multicomponent mixtures extruding from production wastes are carried out, unit for production of composites from different types of waste is presented. Having analyzed dependence of multicomponent mixtures extruding energy requirements on die length and components content at three values of angular rate of screw rotation, we received the values of energy requirements at optimal length of the die, angular speed and percent of binding additives.

  2. Bayesian Kernel Mixtures for Counts

    OpenAIRE

    Canale, Antonio; David B Dunson

    2011-01-01

    Although Bayesian nonparametric mixture models for continuous data are well developed, there is a limited literature on related approaches for count data. A common strategy is to use a mixture of Poissons, which unfortunately is quite restrictive in not accounting for distributions having variance less than the mean. Other approaches include mixing multinomials, which requires finite support, and using a Dirichlet process prior with a Poisson base measure, which does not allow smooth deviatio...

  3. Hybrid pseudomonads engineered by two-step homologous recombination acquire novel degradation abilities toward aromatics and polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Suenaga, Hikaru [National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan). Bioproduction Research Inst.; Nonaka, Kazuhiko; Goto, Masatoshi [Kyushu Univ., Fukuoka (Japan). Dept. of Bioscience and Biotechnology; Fujihara, Hidehiko; Furukawa, Kensuke [Beppu Univ. (Japan). Dept. of Fermentation and Food Science

    2010-10-15

    Pseudomonas pseudoalcaligenes KF707 possesses a chromosomally encoded bph gene cluster responsible for the catabolism of biphenyl and polychlorinated biphenyls. Previously, we constructed chimeric versions of the bphA1 gene, which encodes a large subunit of biphenyl dioxygenase, by using DNA shuffling between bphA1 genes from P. pseudoalcaligenes KF707 and Burkholderia xenovorans LB400. In this study, we demonstrate replacement of the bphA1 gene with chimeric bphA1 sequence within the chromosomal bph gene cluster by two-step homologous recombination. Notably, some of the hybrid strains acquired enhanced and/or expanded degradation capabilities for specific aromatic compounds, including single aromatic hydrocarbons and polychlorinated biphenyls. (orig.)

  4. Draft Genome Sequence of Polychlorinated Biphenyl-Dechlorinating Dehalococcoides mccartyi Strain SG1, Which Carries a Circular Putative Plasmid

    OpenAIRE

    Wang, Shanquan; Chng, Kern Rei; Wu, Chen; Wilm, Andreas; Nagarajan, Niranjan; HE, Jianzhong

    2014-01-01

    Dehalococcoides mccartyi strain SG1, isolated from digester sludge, dechlorinates polychlorinated biphenyls (PCBs) to lower congeners. Here we report the draft genome sequence of SG1, which carries a 22.65 kbp circular putative plasmid.

  5. Environmental exposure to polychlorinated biphenyls (PCBs) and dioxins : Consequences for longterm neurological and cognitive development of the child lactation

    NARCIS (Netherlands)

    Boersma, ER; Lanting, Caren; Koletzko, B; Michaelsen, KF; Hernell, O

    2000-01-01

    Polychlorinated biphenyls (PCBs) and dioxins are environmental pollutants. Prenatally, as well as postnatally through breast feeding, large amounts are transferred from mother to the child. Formula is free of these substances. Considering their potential developmental neurotoxicity, we investigated

  6. Mixed function oxidase dependent biotransformation of polychlorinated biphenyls by different species of fish from the North Sea

    DEFF Research Database (Denmark)

    Mehrtens, G.; Laturnus, F.

    1999-01-01

    Mixed function oxidase (MFO) dependent biotransformation of polychlorinated biphenyls (PCBs) was measured in three different fish species from the North Sea. Liver microsomes of plaice (Pleuronectes platessa), dab (Limanda limanda) and cod (Gadus morhua) were isolated and incubated with different...

  7. Rapid Detection of Polychlorinated Biphenyls at Trace Levels in Real Environmental Samples by Surface-Enhanced Raman Scattering

    OpenAIRE

    Zhengjun Zhang; Yu Huang; Zhengcao Li; Xian Zhang; Qin Zhou

    2011-01-01

    Detection of trace levels of persistent pollutants in the environment is difficult but significant. Organic pollutant homologues, due to their similar physical and chemical properties, are even more difficult to distinguish, especially in trace amounts. We report here a simple method to detect polychlorinated biphenyls (PCBs) in soil and distilled spirit samples by the surface-enhanced Raman scattering technique using Ag nanorod arrays as substrates. By this method, polychlorinated biphenyls ...

  8. Analysis of asphalt mixtures on town roads

    OpenAIRE

    Glavica, Primož

    2006-01-01

    Asphalt mixtures are most commonly used composite for construction of top layers of different drive ways. By definition asphalt mixtures are composed of crushed rock, fill, bitumen and additives. Percentage of individual components wary according to the purpose asphalt mixture is to be used for. Asphalt mixtures must be capable of enduring different types of load. According to the type of load asphalt mixtures are divided into asphalt mixtures used for supporting layers and asp...

  9. The effects of pruning and nodal adventitious roots on polychlorinated biphenyl uptake by Cucurbita pepo grown in field conditions

    International Nuclear Information System (INIS)

    Two cultivation techniques (i-pruning and ii-nodal adventitious root encouragement) were investigated for their ability to increase PCB phytoextraction by Cucurbita pepo ssp pepo cv. Howden (pumpkin) plants in situ at a contaminated industrial site in Ontario (Aroclor 1248, mean soil [PCB] = 5.6 μg g-1). Pruning was implemented to increase plant biomass close to the root where PCB concentration is known to be highest. This treatment was found to have no effect on final shoot biomass or PCB concentration. However, material pruned from the plant is not included in the final shoot biomass. The encouragement of nodal adventitious roots at stem nodes did significantly increase the PCB concentration in the primary stem, while not affecting shoot biomass. Both techniques are easily applied cultivation practices that may be implemented to decrease phytoextraction treatment time. - Research highlights: → Presence of nodal adventitious roots do increase phytoextraction efficiency. → Pruning may increase the biomass of pumpkin plants during phytoextraction. → [Aroclor 1248] decreases in plant tissue with increasing distance from the root. - The application of cultivation practices (pruning and nodal adventitious root encouragement) increases phytoextraction of PCBs in C. pepo.

  10. Relationships of Polychlorinated Biphenyls and Dichlorodiphenyldichloroethylene (p,p’-DDE) with Testosterone Levels in Adolescent Males

    Science.gov (United States)

    Gallo, Mia V.; Deane, Glenn D.; Nelder, Kyrie R.; DeCaprio, Anthony P.; Jacobs, Agnes

    2013-01-01

    Background: Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized. Objectives: In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p´-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 to DeCaprio AP, Jacobs A; Akwesasne Task Force on the Environment. 2014. Relationships of polychlorinated biphenyls and dichlorodiphenyldichloroethylene (p,p´-DDE) with testosterone levels in adolescent males. Environ Health Perspect 122:304–309; http://dx.doi.org/10.1289/ehp.1205984 PMID:24398050

  11. Torsion sensitivity in NMR of aligned molecules: study on various substituted biphenyls.

    Science.gov (United States)

    Sahakyan, Aleksandr B; Shahkhatuni, Aleksan G; Shahkhatuni, Astghik A; Panosyan, Henry A

    2008-02-01

    To estimate the torsion sensitivity of dipolar coupling, biphenylic molecules were chosen as probes due to their relatively simple structure and the surprisingly high ambiguity of the only flexible parameter-the interring torsion angle. Solution structures of 4,4'-dibromobiphenyl and 4,4'-diiodobiphenyl are reported for the first time in two liquid crystals I52 and ZLI 1695. The comparison of NMR structures of various para-substituted biphenyls (BPs), calculated by the additive potential maximum entropy (APME) approach, shows that the small spread of torsion angle values in case of different solvents and para-substituents is in good agreement with theoretical expectations from hybrid density functional theory (DFT) methods. Furthermore, the real structural changes of interring torsion and the prevalence of solvent effects over para-halosubstitution can be correctly revealed from these small fluctuations. PMID:18095265

  12. Synthesis and biological evaluation of nitric oxide-releasing sixalkoxyl biphenyl derivatives as anticancer agents

    Institute of Scientific and Technical Information of China (English)

    Xiang Wen Kong; Yi Hua Zhang; Li Dai; Hui Ji; Yi Sheng Lai; Si Xun Peng

    2008-01-01

    A series of novel nitric oxide-donating sixalkoxyl biphenyl derivatives (14a-i)were synthesized by coupling furoxan with alkoxyl biphenyl skeleton using amino acids as the spacers,and their cytotoxicity against HepG2 cells in vitro were evaluated by MTr method.It was found that 14c,14d,14f,14i,14j and 14k showed more potent cytotoxic activities than control 5-fluorouracil.NO release assay of target compounds indicated that the maximum amount of NO released by most active compounds 14c and 14j was about 6 x 10-2μmol/L,whereas 14a and 14h with very weak activity only released NO of 1 x 10-μmol/L.

  13. Studies on the transformation of selected polychlorinated biphenyl congeners by Pseudomonas strain LB 400

    International Nuclear Information System (INIS)

    Some of the main factors influencing the degradation of certain PCB congeners by resting cells of Pseudomonas strain LB 400 were characterized. The significance of the carbon source used for growth was studied by comparison of rates of PCB transformation by cells grown on biphenyl and other carbon sources. PCB transformation was studied in resting cells grown on glucose and glycerol. Supplementation of the degradation medium with biphenyl significantly decreased the rate of PCB congener transformation. The presence of glycerol or glucose did not affect PCB transformation rates. The study showed that in the treatment of contaminated soils, resting cells lose their viability and PCB transforming ability, such that, in the absence of a growth substrate, soil would have to be reinoculated to maintain PCB biodegradation. 15 refs., 2 tabs., 5 figs

  14. Polychlorinated Biphenyl-77 Induces Adipocyte Differentiation and Proinflammatory Adipokines and Promotes Obesity and Atherosclerosis

    OpenAIRE

    Arsenescu, Violeta; Arsenescu, Razvan I; King, Victoria; Swanson, Hollie; Cassis, Lisa A.

    2008-01-01

    Background Obesity, an inflammatory condition linked to cardiovascular disease, is associated with expansion of adipose tissue. Highly prevalent coplanar polychlorinated biphenyls (PCBs) such as 3,3′,4,4′-tetrachlorobiphenyl (PCB-77) accumulate in adipose tissue because of their lipophilicity and increase with obesity. However, the effects of PCBs on adipocytes, obesity, and obesity-associated cardiovascular disease are unknown. Objectives In this study we examined in vitro and in vivo effect...

  15. Relationships of Polychlorinated Biphenyls and Dichlorodiphenyldichloroethylene (p,p’-DDE) with Testosterone Levels in Adolescent Males

    OpenAIRE

    Schell, Lawrence M.; Gallo, Mia V.; Deane, Glenn D.; Nelder, Kyrie R.; DeCaprio, Anthony P; Jacobs, Agnes; ,

    2013-01-01

    Background: Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized. Objectives: In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p´-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 ...

  16. Polychlorinated biphenyls in serum of the Siberian Yupik people from St. Lawrence Island, Alaska

    OpenAIRE

    Carpenter, David O.; DeCaprio, Anthony P; O’Hehir, David; Akhtar, Farooq; Johnson, Glenn.; Scrudato, Ronald J.; Apatiki, Lucy; Kava, Jane; Gologergen, Jesse; Miller, Pamela K.; Eckstein, Lorraine

    2005-01-01

    Objectives. To determine serum levels of polychlorinated biphenyls (PCBs) in Siberian Yupik adults from St. Lawrence Island, Alaska, and to determine the relative contribution of atmospheric transport of PCBs and local contamination to body burdens. Study Design. Siberian Yupiks of various ages were recruited from three populations: residents of the village of Gambell, residents of the village of Savoonga who did not have family hunting camps near the Northeast Cape (NEC), a Formerly Used Def...

  17. Metabolism of chlorobiphenyls by a variant biphenyl dioxygenase exhibiting enhanced activity toward dibenzofuran

    International Nuclear Information System (INIS)

    Highlights: ► Burkholderia xenovorans LB400 biphenyl dioxygenase (BphAELB400) metabolizes PCBs. ► Asn338Gln/Leu409Phe double mutation speeds up electron transfer of enzyme reaction. ► We tested how the mutations affect the PCB-degrading abilities of BphAELB400 variants. ► The same mutations also broaden the PCB substrate range of BphAELB400 variants. -- Abstract: The biphenyl dioxygenase of Burkholderia xenovorans LB400 (BphAELB400) catalyzes the dihydroxylation of biphenyl and of several polychlorinated biphenyls (PCBs) but it poorly oxidizes dibenzofuran. In this work we showed that BphAERR41, a variant which was previously found to metabolize dibenzofuran more efficiently than its parent BphAELB400, metabolized a broader range of PCBs than BphAELB400. Hence, BphAERR41 was able to metabolize 2,6,2′,6′-, 3,4,3′,5′- and 2,4,3′,4′-tetrachlorobiphenyl that BphAELB400 is unable to metabolize. BphAERR41 was obtained by changing Thr335Phe336Asn338Ile341Leu409 of BphAELB400 to Ala335Met336Gln338Val341Phe409. Site-directed mutagenesis was used to create combinations of each substitution, in order to assess their individual contributions. Data show that the same Asn338Glu/Leu409Phe substitution that enhanced the ability to metabolize dibenzofuran resulted in a broadening of the PCB substrates range of the enzyme. The role of these substitutions on regiospecificities toward selected PCBs is also discussed.

  18. Metabolism of chlorobiphenyls by a variant biphenyl dioxygenase exhibiting enhanced activity toward dibenzofuran

    Energy Technology Data Exchange (ETDEWEB)

    Viger, Jean-Francois; Mohammadi, Mahmood; Barriault, Diane [Institut National de la Recherche Scientifique, INRS-Institut Armand-Frappier, Laval, Quebec, Canada H4K 1C2 (Canada); Sylvestre, Michel, E-mail: Michel.Sylvestre@iaf.inrs.ca [Institut National de la Recherche Scientifique, INRS-Institut Armand-Frappier, Laval, Quebec, Canada H4K 1C2 (Canada)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer Burkholderia xenovorans LB400 biphenyl dioxygenase (BphAE{sub LB400}) metabolizes PCBs. Black-Right-Pointing-Pointer Asn338Gln/Leu409Phe double mutation speeds up electron transfer of enzyme reaction. Black-Right-Pointing-Pointer We tested how the mutations affect the PCB-degrading abilities of BphAE{sub LB400} variants. Black-Right-Pointing-Pointer The same mutations also broaden the PCB substrate range of BphAE{sub LB400} variants. -- Abstract: The biphenyl dioxygenase of Burkholderia xenovorans LB400 (BphAE{sub LB400}) catalyzes the dihydroxylation of biphenyl and of several polychlorinated biphenyls (PCBs) but it poorly oxidizes dibenzofuran. In this work we showed that BphAE{sub RR41}, a variant which was previously found to metabolize dibenzofuran more efficiently than its parent BphAE{sub LB400}, metabolized a broader range of PCBs than BphAE{sub LB400}. Hence, BphAE{sub RR41} was able to metabolize 2,6,2 Prime ,6 Prime -, 3,4,3 Prime ,5 Prime - and 2,4,3 Prime ,4 Prime -tetrachlorobiphenyl that BphAE{sub LB400} is unable to metabolize. BphAE{sub RR41} was obtained by changing Thr335Phe336Asn338Ile341Leu409 of BphAE{sub LB400} to Ala335Met336Gln338Val341Phe409. Site-directed mutagenesis was used to create combinations of each substitution, in order to assess their individual contributions. Data show that the same Asn338Glu/Leu409Phe substitution that enhanced the ability to metabolize dibenzofuran resulted in a broadening of the PCB substrates range of the enzyme. The role of these substitutions on regiospecificities toward selected PCBs is also discussed.

  19. Plasma Levels of Polychlorinated Biphenyls, Non-Hodgkin Lymphoma, and Causation

    OpenAIRE

    Kohles, Sean S.; Freeman, Michael D

    2012-01-01

    Polychlorinated biphenyls (PCBs) are synthetic chlorinated hydrocarbons that have extensively polluted the environment and bioaccumulated in the food chain. PCBs have been deemed to be probable carcinogens by the Environmental Protection Agency, and exposure to high levels of PCBs has been consistently linked to increased risk of non-Hodgkin lymphoma (NHL). In the present article we present a forensic epidemiologic evaluation of the causal relationship between NHL and elevated PCB levels via ...

  20. Ship-source pollution by polychlorinated biphenyls and brominated flame retardants

    OpenAIRE

    ČULIN, Jelena; Bielić, Toni

    2015-01-01

    Polychlorinated biphenyls (PCBs) and brominated flame retardants (BFRs) are groups of anthropogenic contaminants that have been routinely used in many applications for several decades. Prior to the discovery of their detrimental health effects and subsequent implementation of regulatory measures they were widely applied in shipbuilding. They are still found onboard active and inactive ships and pose a risk to human and environment. Therefore, it is important to continue to carry out preven...

  1. Effects of polychlorinated biphenyls on maternal odor conditioning in rat pups

    OpenAIRE

    Cromwell, Howard C.; Johnson, Asia; McKnight, Logan; Horinek, Maegan; Asbrock, Christina; Burt, Shannon; Jolous-Jamshidi, Banafsheh; Meserve, Lee A.

    2007-01-01

    Polychlorinated biphenyls (PCBs) are pervasive environmental contaminants that can have damaging effects on physiologic, motoric and cognitive function. Results from studies on PCBs and behavior have shown that exposure can alter learning and memory processes and that these shifts in cognitive abilities can be related to changes in hormonal and neural function. Little experimentation has been done on the impact of exposure to PCBs on social and emotional development. Previous work has shown t...

  2. Neurodevelopmental toxicity of prenatal polychlorinated biphenyls (PCBs) by chemical structure and activity: a birth cohort study

    OpenAIRE

    Park Hye-Youn; Hertz-Picciotto Irva; Sovcikova Eva; Kocan Anton; Drobna Beata; Trnovec Tomas

    2010-01-01

    Abstract Background Polychlorinated biphenyls (PCBs) are ubiquitous environmental toxins. Although there is growing evidence to support an association between PCBs and deficits of neurodevelopment, the specific mechanisms are not well understood. The potentially different roles of specific PCB groups defined by chemical structures or hormonal activities e.g., dioxin-like, non-dioxin like, or anti-estrogenic PCBs, remain unclear. Our objective was to examine the association between prenatal ex...

  3. Alteration of rat fetal cerebral cortex development after prenatal exposure to polychlorinated biphenyls

    OpenAIRE

    Naveau, Elise; Pinson, Anneline; GERARD, Arlette; Nguyen, Laurent; Charlier, Corinne; Thomé, Jean-Pierre; Zoeller, Robert Thomas; Bourguignon, Jean-Pierre; Parent, Anne-Simone

    2014-01-01

    Polychlorinated biphenyls (PCBs) are environmental contaminants that persist in environment and human tissues. Perinatal exposure to these endocrine disruptors causes cognitive deficits and learning disabilities in children. These effects may involve their ability to interfere with thyroid hormone (TH) action. We tested the hypothesis that developmental exposure to PCBs can concomitantly alter TH levels and TH-regulated events during cerebral cortex development: progenitor proliferation, cell...

  4. Polychlorinated Biphenyls and Leukocyte Telomere Length: An Analysis of NHANES 1999–2002

    OpenAIRE

    Franco Scinicariello; Buser, Melanie C.

    2015-01-01

    Polychlorinated biphenyls (PCBs) induce the expression of the proto-oncogene c-myc which has a role in cellular growth and proliferation programs. The c-myc up-regulates the telomerase reverse transcriptase which adds the telomeres repeating sequences to the chromosomal ends to compensate for the progressive loss of telomeric sequence. We performed multivariate linear regression to analyze the association of PCBs, polychlorinated dibenzo-p-dioxins, and 1,2,3,4,6,7,8-heptachlorodibenzofuran wi...

  5. Tissue damage after acute intoxication by polychlorinated biphenyls (PCBs) in cockroaches Blattella germanica

    OpenAIRE

    Lambiase, S; Zhang, Y.; P. Morbini; M. Fasola

    2009-01-01

    It is common knowledge that polychlorinated biphenyls (PCBs) represent a serious threat to the health of both vertebrates and invertebrates. As far as the former are concerned, especially as regards human beings, a broad literature describes the direct and indirect effects induced by the PCBs on their systems and organs. Among invertebrates, the information available is mostly related to arthropods and is, however, very scarce. The aim of this work was to evaluate the effects of polychlorinat...

  6. A Preliminary Link between Hydroxylated Metabolites of Polychlorinated Biphenyls and Free Thyroxin in Humans

    OpenAIRE

    Eveline Dirinck; Dirtu, Alin C.; Govindan Malarvannan; Adrian Covaci; Jorens, Philippe G.; Van Gaal, Luc F.

    2016-01-01

    Background: Polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (HO-PCBs) interfere with thyroid hormone action both in vitro and in vivo. However, epidemiologic studies on the link between PCB exposure and thyroid function have yielded discordant results, while very few data are available for HO-PCBs. Objectives: Our study aimed at investigating the relationship between clinically available markers of thyroid metabolism and serum levels of both PCBs and HO-PCBs. Subjects and ...

  7. Effects of Chinese domestic polychlorinated biphenyls (PCBs) on gonadal differentiation in Xenopus laevis.

    OpenAIRE

    Qin, Zhan-Fen; Zhou, Jing-Ming; Chu, Shao-Gang; Xu, Xiao-Bai

    2003-01-01

    To determine whether polychlorinated biphenyls (PCBs) influence gonadal differentiation in Xenopus laevis, tadpoles were exposed to two Chinese domestic PCBs (PCB3 and PCB5 from Nieuwkoop and Faber stage 46/47 to complete metamorphosis. Gonads were characterized using a dissecting microscope. The control X. laevis had normal ovaries or testes in gross morphology, whereas obviously abnormal testes including ovotestes were found in PCB3- and PCB5-exposed groups. Ovotestes were characterized by ...

  8. Prenatal Exposure to Polychlorinated Biphenyls and Postnatal Growth: A Structural Analysis

    OpenAIRE

    Lamb, Matthew R.; Taylor, Sylvia; Liu, Xinhua; Wolff, Mary S.; Borrell, Luisa; Matte, Thomas D; Susser, Ezra S.; Factor-Litvak, Pam

    2005-01-01

    Normal endocrine function in utero and early in childhood influences later height and weight attainment. Polychlorinated biphenyls (PCBs) are persistent environmental contaminants with suspected endocrine-disrupting properties. PCBs may mimic or inhibit hormone and endocrine processes based in part on their structural configuration, with non-ortho-substituted PCBs having a coplanar orientation and ortho-substituted PCBs becoming increasingly noncoplanar. Coplanar and noncoplanar PCBs have kno...

  9. Biomonitoring and Elimination of Perfluorinated Compounds and Polychlorinated Biphenyls through Perspiration: Blood, Urine, and Sweat Study

    OpenAIRE

    Stephen J. Genuis; Sanjay Beesoon; Detlef Birkholz

    2013-01-01

    Perfluorinated compounds (PFCs) are man-made organofluorine chemicals manufactured and marketed for their stain-resistant properties. Polychlorinated biphenyls (PCBs) are anthropogenic organochlorine compounds previously used in various industrial and chemical applications prior to being banned in the Western world in the 1970s. Both PFCs and PCBs are persistent contaminants within the human organism and both have been linked to adverse health sequelae. Data is lacking on effective means to f...

  10. Polychlorinated biphenyls fractioning assessment in aqueous bioremediation assy with phanerochaete chrysosporium

    OpenAIRE

    Sangely, Matthieu; Sablayrolles, Caroline; Vialle, Claire; Strehaiano, Pierre; Thannberger, Laurent; Vignoles, Mireille

    2009-01-01

    Thanks to growing environmental concerns in public opinion, bioremediation processes are more and more used to decontaminate soils from organic compounds. Polychlorinated biphenyls (PCBs) are known to be world wide spread persistent organic pollutants (POPs). The white rot fungus Phanerochaete chrysosporium is able to degrade PCBs in water, and soil As POPs, PCBs can also be adsorbed onto organic matter, such as Phanerochaete chrysosporium mycelium. This study aims at estimating the fractioni...

  11. Oculodermatological findings in workers with occupational exposure to polychlorinated biphenyls (PCBs).

    OpenAIRE

    Fischbein, A; Rizzo, J N; Solomon, S J; Wolff, M S

    1985-01-01

    Oculodermatological findings, such as hypersecretion of the Meibomian glands, swelling of the upper eyelids and hyperpigmentation of the conjunctivae are considered typical of "PCB poisoning." They were common clinical manifestations of yusho and yu-cheng, two epidemics in Japan and Taiwan caused by the ingestion of rice cooking oil contaminated with polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans. To investigate the prevalence of such abnormalities in a population with lon...

  12. Prenatal and postnatal exposure to polychlorinated biphenyls and child size at 24 months of age

    OpenAIRE

    Jackson, Leila W.; Lynch, Courtney D.; Kostyniak, Paul J.; McGuinness, Bridget M; Buck Louis, Germaine M.

    2009-01-01

    Research suggests that exposure to polychlorinated biphenyls (PCBs) may result in decreased child growth, though the critical window(s) are unclear. We investigated the association between PCBs and child size at age 24 months (n=44). PCBs were measured in 1st trimester serum, breast milk, and child serum at age 24 months, and dichotomized at the median. Age- and gender-specific z-scores were calculated for anthropometric measures. Using linear regression, we observed no significant changes in...

  13. Perinatal exposure to polychlorinated biphenyls and dioxins and its effect on neonatal neurological development

    OpenAIRE

    Huisman, Martijn; Koopman-Esseboom, Corine; Fidler, Vaclav; Hadders-Algra, Mijna; Paauw, Cornelis; Tuinstra, L.G.M.Th.; Weisglas-Kuperus, Nynke; Sauer, Pieter; Touwen, Bert C.; Boersma, Eric

    1995-01-01

    textabstractPolychlorinated biphenyls (PCBs) and dioxins (polychlorinated dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs)) are widespread environmental contaminants which are neurotoxic in animals. Perinatal exposure to PCBs, PCDDs, and PCDFs occurs prenatally via the placenta and postnatally via breast milk. To investigate whether such an exposure affects the neonatal neurological condition, the neurological optimality of 418 Dutch newborns was evaluated with the Prechtl neurological ex...

  14. Polychlorinated biphenyls and reproductive hormones in female polar bears at Svalbard.

    OpenAIRE

    Haave, Marte; Ropstad, Erik; Derocher, Andrew E; Lie, Elisabeth; Dahl, Ellen; Wiig, Øystein; Skaare, Janneche U; Jenssen, Bjørn Munro

    2003-01-01

    High concentrations of polychlorinated biphenyls (PCBs) in polar bears from Svalbard have increased concern for that population's reproductive health. We examined whether there were associations between the plasma concentrations of PCBs and reproductive hormones [progesterone (P4)] and 17 beta-estradiol (E2)] in free-living female polar bears from Svalbard. Concentrations of P4 depended on reproductive status, and concentrations were lowest in females with offspring--females with cubs and fem...

  15. Evaluating Health Risks from Inhaled Polychlorinated Biphenyls: Research Needs for Addressing Uncertainty

    OpenAIRE

    Lehmann, Geniece M.; Christensen, Krista; Maddaloni, Mark; Phillips, Linda J.

    2014-01-01

    Background: Indoor air concentrations of polychlorinated biphenyls (PCBs) in some buildings are one or more orders of magnitude higher than background levels. In response to this, efforts have been made to assess the potential health risk posed by inhaled PCBs. These efforts are hindered by uncertainties related to the characterization and assessment of source, exposure, and exposure-response. Objectives: We briefly describe some common sources of PCBs in indoor air and estimate the contribut...

  16. Immunologic effects of background exposure to polychlorinated biphenyls and dioxins in Dutch preschool children.

    OpenAIRE

    Weisglas-Kuperus, Nynke; Patandin, Svati; Berbers, G A; Sas, Theo; Sauer, Pieter; Hooijkaas, Herbert; Mulder, Paul

    2000-01-01

    textabstractPrenatal exposure to polychlorinated biphenyls (PCBs) and dioxins is associated with changes in the T-cell lymphocyte population in healthy Dutch infants. We investigated whether these changes persist into later childhood and whether background exposure to PCBs and dioxins is associated with the prevalence of infectious or allergic diseases and humoral immunity at preschool age. The total study group consisted of 207 healthy mother-infant pairs. We estimated prenatal exposure to P...

  17. CONTAMINATION OF POLYCHLORINATED BIPHENYLS IN FISHES LEADING TO TOXICITY IN FISH CONSUMING POPULATION

    OpenAIRE

    Govind Pandey; Madhuri S.; A.B. Shrivastav

    2012-01-01

    The pollution of rivers and streams with chemical contaminants has become one of the most critical environmental problems. Similar to humans and other species of animals, fish have also been found to be polluted with a large number of pollutants/contaminants. Unintentionally added chemicals causing fish toxicity include organochlorine pesticides, polychlorinated biphenyls (PCBs) and other persistent chemicals in feed, chemicals in construction materials, and metabolites and degradation produc...

  18. (Biphenyl-2-yl)bromidobis(2-methyl-tetra-hydro-furan-κO)magnesium(II).

    Science.gov (United States)

    Nordschild, Simon; Wohlgemuth, D; Bolte, Michael

    2009-01-01

    In the title Grignard reagent, [MgBr(C(12)H(9))(C(5)H(10)O)(2)], the Mg centre adopts a distorted tetra-hedral MgCO(2)Br arrangement. The dihedral angle between the two aromatic rings of the biphenyl residue is 44.00 (14)°. Each mol-ecule incorporates one R- and one S-configured 2-methyl-tetra-hydro-furan mol-ecule. PMID:21583743

  19. Polychlorinated biphenyls-induced alterations of thyroid hormone homeostasis and brain development in the rat.

    OpenAIRE

    Morse, D.C.

    1995-01-01

    IntroductionThe work described in this thesis was undertaken to gain insight in the processes involved in the developmental neurotoxicity of polychlorinated biphenyls. It has been previously hypothesized that the alteration of thyroid hormone status by PCBs may be in part responsible for the developmental neurotoxicity of these compounds in humans (Rogan et al. 1986). This is a logical hypothesis, given the well-described effects of PCBs on plasma thyroid hormone levels in adult animals, and ...

  20. Effect of Chemical Structure on the Isobaric and Isochoric Fragility in Polychlorinated Biphenyls

    OpenAIRE

    Roland, C. M.; Casalini, R.

    2005-01-01

    Pressure-volume-temperature data, along with dielectric relaxation measurements, are reported for a series of polychlorinated biphenyls (PCB), differing in the number of chlorine atoms on their phenyl rings. Analysis of the results reveals that with increasing chlorine content, the relaxation times of the PCB become governed to a greater degree by density, rho, relative to the effect of temperature, T. This result is consistent with the respective magnitudes of the scaling exponent, gamma, yi...

  1. Effects of polychlorinated biphenyls and environmental biotransformation products on aquatic nitrification.

    OpenAIRE

    Sayler, G S; Shiaris, M. P.; Beck, W.; Held, S.

    1982-01-01

    The effects of polychlorinated biphenyls (PCBs) on nitrification were examined for pure cultures and natural reservoir samples. PCBs at concentrations greater than 10 microgram liter-1 inhibited nitrification, principally ammonium oxidation, in one of two natural reservoir environments. However, this inhibition could not be reproduced in pure high-cell-density cultures or in previously contaminated reservoir waters. A PCB environmental biotransformation product, p-chlorophenylglyoxylic acid, ...

  2. A stress tensor and QTAIM perspective on the substituent effects of biphenyl subjected to torsion.

    Science.gov (United States)

    Jiajun, D; Maza, J R; Xu, Y; Xu, T; Momen, R; Kirk, S R; Jenkins, S

    2016-10-30

    The Quantum Theory of Atoms in Molecules (QTAIM) defines quantities in 3D space that can be easily obtained from routine quantum chemical calculations. The present investigation shows that local properties can be related quantitatively to measures traditionally connected to experimental data, such as Hammett constants. We consider the specific case of substituted biphenyl to quantify the effects of a torsion φ, 0.0° ≤ φ ≤ 180.0°, of the C-C bond linking the two phenyl rings for C12 H9 -x, where x = N(CH3 )2 , NH2 , CH3 , CHO, CN, NO2, on the entire molecule. QTAIM interpreted Hammett constants, aΔH(rb ) are introduced and constructed using the difference between the H(rb ) value of C12 H9 -x and the C12 H9 -H, biphenyl which is the reference molecule, with a constant of proportionality a. This investigation unexpectedly yields very good or good agreement for the x groups with the Hammett para-, meta-, and ortho-substituent constants and is checked against para-substituted benzene. We then proceed to present the interpreted substituent constants of seven new biphenyl substituent groups, where tabulated Hammett substituent constant values are not available; y = SiH3 , ZnCl, COOCH3 , SO2 NH2 , SO2 OH, COCl, CB3 . Consistency is found for the QTAIM interpreted biphenyl substituent constants of the seven new groups y independently using the stress tensor polarizability Pσ . In addition, a selection of future applications is discussed that highlight the usefulness of this approach. © 2016 Wiley Periodicals, Inc. PMID:27546220

  3. CLOSURE REPORT FOR CORRECTIVE ACTION UNIT 528: POLYCHLORINATED BIPHENYLS CONTAMINATION NEVADA TEST SITE, NEVADA

    Energy Technology Data Exchange (ETDEWEB)

    BECHTEL NEVADA

    2006-09-01

    This Closure Report (CR) describes the closure activities performed at CAU 528, Polychlorinated Biphenyls Contamination, as presented in the Nevada Division of Environmental Protection (NDEP)-approved Corrective Action Plan (CAP) (US. Department of Energy, National Nuclear Security Administration Nevada Site Office [NNSAINSO], 2005). The approved closure alternative was closure in place with administrative controls. This CR provides a summary of the completed closure activities, documentation of waste disposal, and analytical data to confirm that the remediation goals were met.

  4. Field-derived Henry's law constants for polychlorinated biphenyls in oceanic waters

    OpenAIRE

    Gioia, Rosalinda; Dachs, Jordi; Lohmann, Rainer; Jones, Kevin C.; Nizzeto, Luca

    2010-01-01

    Accurate knowledge of Henry's law constants (Kaw) is very important for fate and transport studies of organic chemicals. Here field-derived Kaw values for polychlorinated biphenyl (PCB) congeners (PCBs 28, 49, 52, 118, 138, 149, and 153) were determined in the open Atlantic Ocean, at locations where air and seawater were assumed to be at equilibrium. Field-based Kaw values were derived from air and seawater samples simultaneously collected at these locations, and their relationship with tempe...

  5. Chlororganische Pestizide, polychlorierte Biphenyle und potentiell toxische Schwermetalle in Organproben von Seeadlern und Habichten

    OpenAIRE

    Kenntner, Norbert

    2010-01-01

    In the present study, we examined organs of 145 white-tailed eagles (Haliaeetus albicilla) from Germany and 5 specimen from Austria, as well as 62 northern goshawks (Accipiter gentilis) from different regions of Germany for their organ concentrations of chlorinated pesticides, polychlorinated biphenyls (PCB) and potentially toxic heavy metals. We proved a significant decline of DDT concentrations in livers of 127 white-tailed eagles (WTE) collected between 1990 and 2001. Considering the final...

  6. Cometabolic oxidation of polychlorinated biphenyls in soil with a surfactant-based field application vector.

    OpenAIRE

    Lajoie, C. A.; Layton, A C; Sayler, G. S.

    1994-01-01

    Polychlorinated biphenyl (PCB)-degradative genes, under the control of a constitutive promoter, were cloned into a broad-host-range plasmid and a transposon. These constructs were inserted into a surfactant-utilizing strain, Pseudomonas putida IPL5, to create a field application vector (FAV) in which a surfactant-degrading organism cometabolizes PCB. By utilizing a surfactant not readily available to indigenous populations and a constitutive promoter, selective growth and PCB-degradative gene...

  7. Anaerobic degradation of Polychlorinated Biphenyls (PCBs) and Polychlorinated Biphenyls Ethers (PBDEs), and microbial community dynamics of electronic waste-contaminated soil

    International Nuclear Information System (INIS)

    Environmental contamination caused by electronic waste (e-waste) recycling is attracting increasing attention worldwide because of the threats posed to ecosystems and human safety. In the present study, we investigated the feasibility of in situ bioremediation of e-waste-contaminated soils. We found that, in the presence of lactate as an electron donor, higher halogenated congeners were converted to lower congeners via anaerobic halorespiration using ferrous ions in contaminated soil. The 16S rRNA gene sequences of terminal restriction fragments indicated that the three dominant strains were closely related to known dissimilatory iron-reducing bacteria (DIRB) and those able to perform dehalogenation upon respiration. The functional species performed the activities of ferrous oxidation to ferric ions and further ferrous reduction for dehalogenation. The present study links iron cycling to degradation of halogenated materials in natural e-waste-contaminated soil, and highlights the synergistic roles of soil bacteria and ferrous/ferric ion cycling in the dehalogenation of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs). - Highlights: • The biodegradation PCBs and PBDEs in e-waste contaminated soils was studied. • DIRB and arylhalorespiring bacteria were responsive to dehalogenation respiration. • Soil bacteria and Fe ion cycling play synergistic roles in dehalogenation

  8. Anaerobic degradation of Polychlorinated Biphenyls (PCBs) and Polychlorinated Biphenyls Ethers (PBDEs), and microbial community dynamics of electronic waste-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Song, Mengke [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate University of Chinese Academy of Sciences, Beijing 100039 (China); Luo, Chunling, E-mail: clluo@gig.ac.cn [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Li, Fangbai [Guangdong Institute of Eco-environmental and Soil Sciences, Guangzhou 510650 (China); Jiang, Longfei [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Wang, Yan [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Zhang, Dayi [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Zhang, Gan [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2015-01-01

    Environmental contamination caused by electronic waste (e-waste) recycling is attracting increasing attention worldwide because of the threats posed to ecosystems and human safety. In the present study, we investigated the feasibility of in situ bioremediation of e-waste-contaminated soils. We found that, in the presence of lactate as an electron donor, higher halogenated congeners were converted to lower congeners via anaerobic halorespiration using ferrous ions in contaminated soil. The 16S rRNA gene sequences of terminal restriction fragments indicated that the three dominant strains were closely related to known dissimilatory iron-reducing bacteria (DIRB) and those able to perform dehalogenation upon respiration. The functional species performed the activities of ferrous oxidation to ferric ions and further ferrous reduction for dehalogenation. The present study links iron cycling to degradation of halogenated materials in natural e-waste-contaminated soil, and highlights the synergistic roles of soil bacteria and ferrous/ferric ion cycling in the dehalogenation of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs). - Highlights: • The biodegradation PCBs and PBDEs in e-waste contaminated soils was studied. • DIRB and arylhalorespiring bacteria were responsive to dehalogenation respiration. • Soil bacteria and Fe ion cycling play synergistic roles in dehalogenation.

  9. Global distribution and local impacts of inadvertently generated polychlorinated biphenyls in pigments.

    Science.gov (United States)

    Guo, Jia; Capozzi, Staci L; Kraeutler, Thomas M; Rodenburg, Lisa A

    2014-01-01

    The non-Aroclor congener 3,3'-dichlorobiphenyl (PCB 11) has been recently detected in air, water, sediment, and biota. It has been known since at least the 1970s that this congener is produced inadvertently during the production of certain organic pigments. PCB 11 was previously measured at parts-per-billion (ppb) levels in various printed materials obtained in the US. In this work, PCB 11 was detected in samples of common consumer goods including magazines, advertisements, maps, postcards, brochures, napkins, and garments from 26 countries in five continents at concentrations ranging from 0.27 to 86 ppb. Leaching tests confirmed that PCB 11 could be released from these materials into water. We also examined whether the known sources of PCB 11 were large enough to account for the levels of PCB 11 measured in the air, water, soil and sediment of the Delaware River Basin. A mass flow analysis suggests that the outflows and sequestration of PCB 11 in the basin total between 30 and 280 kg y(-1). If PCB 11 concentrations in pigments were at the maximum average (125 ppm) allowed under the Toxic Substances Control Act (TSCA), the estimated input of PCB 11 to the Delaware River Basin would be on the order of 42 kg y(-1). Despite the large uncertainty in these numbers, the results suggest that pigments may plausibly account for the levels of PCB 11 measured in the environment. PMID:24965012

  10. Hydroxylated and methylsulfonyl polychlorinated biphenyl metabolites in albatrosses from Midway Atoll, North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Klasson-Wehler, E.; Bergman, A.; Athanasiadou, M. [Stockholm Univ. (Sweden)] [and others

    1998-08-01

    Concentrations of hydroxylated metabolites of polychlorinated biphenyls (PCBs) (OH-PCBs) and methylsulfonyl metabolites of PCBs (MeSO{sub 2}-PCBs) were determined in plasma and liver of albatrosses collected from the Midway Atoll in the central North Pacific Ocean. The mean total concentrations of OH-PCBs in plasma of Laysan albatrosses (Diomedea immutabilis) and black-footed albatrosses (Diomedea nigripes) were 11.5 and 27.1 ng/g wet weight, respectively. Total concentrations of OH-PCBs were only one- to fivefold less than those of total PCBs. 4-hydroxy-2,2{prime},3,4{prime},5,5{prime},6-heptachlorinated biphenyl and 4-hydroxy-2,2{prime},3,4{prime},5,5{prime}-hexachlorinated biphenyl were the predominant polychlorinated biphenylols, constituting 70 to 90% of the total OH-PCBs. Concentrations of MeSO{sub 2}-PCBs in liver were between 10.6 and 77 ng/g, lipid weight, approximately 250 times less than those of total PCBs. The MeSO{sub 2}-PCBs congeners retained in the liver were dominated by those having the methylsulfonyl group in the 3-position.

  11. Polychlorinated biphenyls in eggs and chlorioallantoic membranes of American alligators (Alligator mississippiensis) from coastal South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Cobb, G.P.; Wood, P.D. [Clemson Univ., Pendleton, SC (United States); O`Quinn, M. [South Carolina Governor`s School for Science and Mathematics, Hartsville, SC (United States)

    1997-07-01

    Assessing chemical exposure in threatened or endangered wildlife species presents unique analytical problems. Chorioallantoic membranes (CAMs) have been proposed as surrogate tissues for evaluation of polychlorinated biphenyl (PCB) exposure in oviparous species. Research was undertaken to determine the extent of PCB accumulation in alligators (Alligator mississippiensis) at sites along the coast of South Carolina and to evaluate the utility of CAMs as surrogate tissues for determining PCB concentrations in whole alligator eggs. Polychlorinated biphenyls were found in eggs and CAMs of alligators from both sites examined. Concentrations of PCBs were higher in CAMs (p = 0.02) and eggs (p = 0.001) from sites known to contain chlorinated hydrocarbons than from more pristine sites. Total PCBs partitioned predictably (r{sup 2} > 0.59; p < 0.02) between egg and CAM tissues indicating the utility of CAMs to serve as surrogate tissues when comparing total PCB concentrations in whole eggs. Tetrachloro through octachloro biphenyl homologues and total PCBs in CAMs from reference areas were correlated with concentrations of these homologues in eggs. At contaminated sites, total PCB concentrations in CAMs were correlated with total PCB concentrations in eggs.

  12. Toxicity of hydroxylated polychlorinated biphenyls (HO-PCBs) using the bioluminescent assay Microtox(®).

    Science.gov (United States)

    Bhalla, Renu; Tehrani, Rouzbeh; Van Aken, Benoit

    2016-09-01

    Hydroxylated polychlorinated biphenyls (HO-PCBs) are toxic contaminants which are produced in the environment by biological or abiotic oxidation of PCBs. The toxicity of a suite of 23 mono-hydroxylated derivatives of PCBs and 12 parent PCBs was determined using the bacterial bioluminescent assay Microtox(®). All HO-PCBs tested exhibited higher toxicity than the corresponding parent PCB, with effect concentration 50 % (EC50) ranging from 0.07 to 133 mg L(-1). The highest toxicities were recorded with 4-hydroxylated derivatives of di-chlorinated biphenyls (EC50 = 0.07-0.36 mg L(-1)) and 2-hydroxylated derivatives of tri-chlorinated biphenyls carrying a chlorine substituent on the phenolic ring (EC50 = 0.34-0.48 mg L(-1)). The toxicity of HO-PCBs generally decreased when the degree of chlorination increased. Consistently with this observation, a significant positive correlation was measured between toxicity (measured by EC50) and octanol-water partition coefficient (pK ow) for the HO-PCBs under study (Pearson's correlation coefficient, r = 0.74), which may be explained by the lower solubility and bioavailability generally associated with higher hydrophobicity. This study is the first one which assessed the toxicity of a suite of PCBs and HO-PCBs using the bioluminescent assay Microtox(®), showing an inverse correlation between toxicity and hydrophobicity. PMID:27411941

  13. Marangoni Convection in Binary Mixtures

    CERN Document Server

    Zhang, J; Oron, A; Behringer, Robert P.; Oron, Alexander; Zhang, Jie

    2006-01-01

    Marangoni instabilities in binary mixtures are different from those in pure liquids. In contrast to a large amount of experimental work on Marangoni convection in pure liquids, such experiments in binary mixtures are not available in the literature, to our knowledge. Using binary mixtures of sodium chloride/water, we have systematically investigated the pattern formation for a set of substrate temperatures and solute concentrations in an open system. The flow patterns evolve with time, driven by surface-tension fluctuations due to evaporation and the Soret effect, while the air-liquid interface does not deform. A shadowgraph method is used to follow the pattern formation in time. The patterns are mainly composed of polygons and rolls. The mean pattern size first decreases slightly, and then gradually increases during the evolution. Evaporation affects the pattern formation mainly at the early stage and the local evaporation rate tends to become spatially uniform at the film surface. The Soret effect becomes i...

  14. Preparation of conducting solid mixtures

    International Nuclear Information System (INIS)

    The application of conducting plastic mixtures to the fundamental problem of radiation dosimetry is briefly reviewed. A particular approach to achieving formulations with the necessary characteristics is described. A number of successful mixtures are defined for a number of different specific dosimetry situations. To obtain high quality stable materials requires intense blending and working of the materials at elevated temperatures. One machine that succeeds in this task is the Shonka plastics mixer-extruder. The Shonka mixer is described in complete detail. The procedures used in preparing representative formulations with this device are presented. A number of properties of successful conducting mixtures so prepared are summarized. The conditions required for molding such material are given. Several special welding methods for specific application with these formulations have been devised and are described

  15. Mixtures of skewed Kalman filters

    KAUST Repository

    Kim, Hyoungmoon

    2014-01-01

    Normal state-space models are prevalent, but to increase the applicability of the Kalman filter, we propose mixtures of skewed, and extended skewed, Kalman filters. To do so, the closed skew-normal distribution is extended to a scale mixture class of closed skew-normal distributions. Some basic properties are derived and a class of closed skew. t distributions is obtained. Our suggested family of distributions is skewed and has heavy tails too, so it is appropriate for robust analysis. Our proposed special sequential Monte Carlo methods use a random mixture of the closed skew-normal distributions to approximate a target distribution. Hence it is possible to handle skewed and heavy tailed data simultaneously. These methods are illustrated with numerical experiments. © 2013 Elsevier Inc.

  16. Bayesian Kernel Mixtures for Counts.

    Science.gov (United States)

    Canale, Antonio; Dunson, David B

    2011-12-01

    Although Bayesian nonparametric mixture models for continuous data are well developed, there is a limited literature on related approaches for count data. A common strategy is to use a mixture of Poissons, which unfortunately is quite restrictive in not accounting for distributions having variance less than the mean. Other approaches include mixing multinomials, which requires finite support, and using a Dirichlet process prior with a Poisson base measure, which does not allow smooth deviations from the Poisson. As a broad class of alternative models, we propose to use nonparametric mixtures of rounded continuous kernels. An efficient Gibbs sampler is developed for posterior computation, and a simulation study is performed to assess performance. Focusing on the rounded Gaussian case, we generalize the modeling framework to account for multivariate count data, joint modeling with continuous and categorical variables, and other complications. The methods are illustrated through applications to a developmental toxicity study and marketing data. This article has supplementary material online. PMID:22523437

  17. Detection of potential genetic hazards in complex environmental mixtures using plant cytogenetics and microbial mutagenesis assays. [Arsenic-contaminated groundwater and power plant fly ash extract

    Energy Technology Data Exchange (ETDEWEB)

    Constantin, M J; Lowe, K; Rao, T K; Larimer, F W; Epler, J L

    1980-01-01

    Solid wastes have been characterized to determine their potential hazards to humans and the environment. An arsenic-contaminated ground water sample increased the frequency of histidine revertants in Salmonella typhimurium (TA-98) at 0.025 to 5.000 ..mu..l per plate with Aroclor-induced S-9 liver microsomes. When 2.5 to 75 ..mu..l of the XAD-2 concentrate (12.5-fold, v:v) were used, the mutant frequency was increased in strains TA-98, TA-100, and TA-1537; metabolic activation was not required. Only the XAD-2 concentrate was mutagenic in the Saccharomyces cerevisiae haploid strain XL-7-10B; metabolic activation was not required. The mutagenic principal, which is not known, appears to be at the limit of resolution; hence, the XAD-2 concentration is necessary to demonstrate mutagenic activity. The arsenic-contaminated ground water (0.0625 and 0.125 dilutions) and the power plant fly ash extract (undiluted) increased the frequency of bridges and fragements at anaphase in root tip cells of Hordeum. The fly ash sample was negative in the microbial assays. Results emphasize (1) the need for a battery of assays with different organisms and (2) the potential of a simple assay using plant root tip cells to detect mutagenic activity in complex environmental mixtures.

  18. Thermodynamics of mixtures containing alkoxyethanols

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F., Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, 47071 Valladolid (Spain)], E-mail: jagl@termo.uva.es; Mozo, Ismael; Fuente, Isaias Garcia de la; Cobos, Jose Carlos [G.E.T.E.F., Departamento de Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, 47071 Valladolid (Spain); Riesco, Nicolas [Department of Earth Science and Engineering, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom)

    2008-09-30

    The Flory model is applied to predict the isobaric expansion coefficients, {alpha}{sub P}, isentropic, {kappa}{sub S}, and isothermal, {kappa}{sub T}, compressibilities and speeds of sound, u, of the highly complex mixtures: hydroxyether + alkane, + dibutylether, + 1-butanol or + 2-methoxyethanol, 1-alkanol + alkane, and 1-alkanol + dibutylether. Predictions were obtained using the energetic parameter, {chi}{sub 12}, determined from values of excess enthalpies, H{sup E}, and from values of the excess isochoric internal energies, U{sub V}{sup E}, at equimolar composition. No meaningful differences exist between such predictions. Deviations between experimental and calculated values are lower than 2% for mixtures containing alkoxyethanols. Poorer results are obtained for 1-alkanol + dibutylether mixtures with deviations up to 5%. It is shown that predictions on {alpha}{sub P}, {kappa}{sub S}, {kappa}{sub T}, and u essentially depend on structural effects and not on the orientational effects present in the studied mixtures. Results are improved using {chi}{sub 12} values fitted to molar excess volumes. In this case, deviations are similar to those obtained from semiempirical models as free length theory, collision factor theory, or Nomoto or Junjie equations.

  19. Uphill diffusion in multicomponent mixtures.

    Science.gov (United States)

    Krishna, Rajamani

    2015-05-21

    Molecular diffusion is an omnipresent phenomena that is important in a wide variety of contexts in chemical, physical, and biological processes. In the majority of cases, the diffusion process can be adequately described by Fick's law that postulates a linear relationship between the flux of any species and its own concentration gradient. Most commonly, a component diffuses down the concentration gradient. The major objective of this review is to highlight a very wide variety of situations that cause the uphill transport of one constituent in the mixture. Uphill diffusion may occur in multicomponent mixtures in which the diffusion flux of any species is strongly coupled to that of its partner species. Such coupling effects often arise from strong thermodynamic non-idealities. For a quantitative description we need to use chemical potential gradients as driving forces. The transport of ionic species in aqueous solutions is coupled with its partner ions because of the electro-neutrality constraints; such constraints may accelerate or decelerate a specific ion. When uphill diffusion occurs, we observe transient overshoots during equilibration; the equilibration process follows serpentine trajectories in composition space. For mixtures of liquids, alloys, ceramics and glasses the serpentine trajectories could cause entry into meta-stable composition zones; such entry could result in phenomena such as spinodal decomposition, spontaneous emulsification, and the Ouzo effect. For distillation of multicomponent mixtures that form azeotropes, uphill diffusion may allow crossing of distillation boundaries that are normally forbidden. For mixture separations with microporous adsorbents, uphill diffusion can cause supra-equilibrium loadings to be achieved during transient uptake within crystals; this allows the possibility of over-riding adsorption equilibrium for achieving difficult separations. PMID:25761383

  20. Optimizing Polychlorinated Biphenyl Degradation by Flavonoid-Induced Cells of the Rhizobacterium Rhodococcus erythropolis U23A.

    Directory of Open Access Journals (Sweden)

    Thi Thanh My Pham

    Full Text Available There is evidence that many plant secondary metabolites may act as signal molecules to trigger the bacterial ability to metabolize polychlorinated biphenyls (PCBs during the rhizoremediation process. However, the bases for the PCB rhizoremediation process are still largely unknown. The rhizobacterium Rhodococcus erythropolis U23A is unable to use flavanone as a growth substrate. However, on the basis of an assay that monitors the amount of 4-chlorobenzoate produced from 4-chlorobiphenyl by cells grown co-metabolically on flavanone plus sodium acetate, this flavonoid was previously found to be a potential inducer of the U23A biphenyl catabolic pathway. In this work, and using the same assay, we identified ten other flavonoids that did not support growth, but that acted as inducers of the U23A biphenyl pathway, and we confirmed flavonoid induction of the biphenyl catabolic pathway using quantitative real-time polymerase chain reaction (RT-qPCR on the bphA gene. We also examined the effect of the growth co-substrate on flavonoid induction. Sodium acetate was replaced by glucose, mannose, sucrose, or mannitol, which are sugars found in plant root exudates. The data showed that the level of induction of strain U23A biphenyl-degrading enzymes was significantly influenced by the nature and concentration of the flavonoid in the growth medium, as well as by the substrate used for growth. Sucrose allowed for an optimal induction response for most flavonoids. Some flavonoids, such as flavone and isoflavone, were better inducers of the biphenyl catabolic enzymes than biphenyl itself. We also found that all flavonoids tested in this work were metabolized by strain U23A during co-metabolic growth, but that the metabolite profiles, as well as the level of efficiency of degradation, differed for each flavonoid. To obtain insight into how flavonoids interact with strain U23A to promote polychlorinated biphenyl (PCB degradation, we determined the concentration of

  1. In Vitro and in Silico Analyses for Predicting Hepatic Cytochrome P450-Dependent Metabolic Potencies of Polychlorinated Biphenyls in the Baikal Seal.

    Science.gov (United States)

    Yoo, Jean; Hirano, Masashi; Mizukawa, Hazuki; Nomiyama, Kei; Agusa, Tetsuro; Kim, Eun-Young; Tanabe, Shinsuke; Iwata, Hisato

    2015-12-15

    The aim of this study was to understand the cytochrome P450 (CYP)-dependent metabolic pathway and potency of polychlorinated biphenyls (PCBs) in the Baikal seal (Pusa sibirica). In vitro metabolism of 62 PCB congener mixtures was investigated by using liver microsomes of this species. A decreased ratio of over 20% was observed for CB3, CB4, CB8, CB15, CB19, CB22, CB37, CB54, CB77, and CB105, suggesting the preferential metabolism of low-chlorinated PCBs by CYPs. The highly activated metabolic pathways in Baikal seals that were predicted from the decreased PCBs and detected hydroxylated PCBs (OH-PCBs) were CB22 to 4'OH-CB20 and CB77 to 4'OH-CB79. The total amount of OH-PCBs detected as identified and unidentified congeners accounted for only a 3.8 ± 1.7 mol % of loaded PCBs, indicating many unknown PCB metabolic pathways. To explore factors involved in CYP-dependent PCB metabolism, we examined the relationships among the structural and physicochemical properties of PCBs, the in silico PCB-CYP docking parameters, and the in vitro PCB decreased ratios by principal component analysis. Statistical analysis showed that the decreased PCB ratio was at least partly accounted for by the substituted chlorine number of PCBs and the distance from the Cl-unsubstituted carbon of docked PCBs to the heme Fe in CYP2A and 2B. PMID:26579933

  2. A meta-analysis of relationships between polychlorinated biphenyl exposure and performance across studies of free-ranging tree swallows (Tachycineta bicolor)

    Science.gov (United States)

    Bonier, Frances

    2016-01-01

    Habitats worldwide are increasingly being degraded by human activities, with environmental pollution representing a significant threat to species and ecosystems. The presence of persistent organic chemicals, such as polychlorinated biphenyls (PCBs), has generated concern. Captive experiments and field studies have reported some evidence for detrimental effects of PCB exposure, but also significant variation across studies and species. Here, I use a meta-analytical approach to combine findings across 10 studies investigating effects of PCBs on performance (e.g. reproductive success, offspring growth) in free-ranging tree swallows, a common bioindicator species that accumulates high levels of PCBs at some contaminated sites. Contrary to predictions, five complementary analyses revealed no significant negative association between PCB exposure and performance in tree swallows. In fact, in one analysis, increased PCB exposure was associated with improved reproductive success. Possible explanations for these findings include several limitations of field studies, variation in the toxicity of different PCB congener mixtures found across sites included in the analysis, and variation in the degree of tolerance of PCB exposure among species (with high tolerance found in tree swallows). At this point, the available evidence from field studies does not demonstrate negative impacts of PCB exposure on tree swallow performance. PMID:27152205

  3. A meta-analysis of relationships between polychlorinated biphenyl exposure and performance across studies of free-ranging tree swallows (Tachycineta bicolor).

    Science.gov (United States)

    Bonier, Frances

    2016-04-01

    Habitats worldwide are increasingly being degraded by human activities, with environmental pollution representing a significant threat to species and ecosystems. The presence of persistent organic chemicals, such as polychlorinated biphenyls (PCBs), has generated concern. Captive experiments and field studies have reported some evidence for detrimental effects of PCB exposure, but also significant variation across studies and species. Here, I use a meta-analytical approach to combine findings across 10 studies investigating effects of PCBs on performance (e.g. reproductive success, offspring growth) in free-ranging tree swallows, a common bioindicator species that accumulates high levels of PCBs at some contaminated sites. Contrary to predictions, five complementary analyses revealed no significant negative association between PCB exposure and performance in tree swallows. In fact, in one analysis, increased PCB exposure was associated with improved reproductive success. Possible explanations for these findings include several limitations of field studies, variation in the toxicity of different PCB congener mixtures found across sites included in the analysis, and variation in the degree of tolerance of PCB exposure among species (with high tolerance found in tree swallows). At this point, the available evidence from field studies does not demonstrate negative impacts of PCB exposure on tree swallow performance.

  4. Enantiomer Separation of α-Dimethyl Dicarboxylate Biphenyl and Related Biphenyl Compounds by Normal Phase HPLC on Polysaccharide Based Chiral Stationary Phases

    Institute of Scientific and Technical Information of China (English)

    LIU,Yue-Qi(刘月启); HAN,Xiao-Qian(韩小茜); Qi,Bang-Feng(齐邦峰); LIU,Chun-Hui(柳春辉); LI,Yong-Min(李永民); CHEN,Li-Ren(陈立仁)

    2002-01-01

    Cellulose tris(4-methylphenylcarbamate), amylose tris(3,5-dimethylpphenylcarbamate) and amylose tris (phenylcarbamate)were prepared by the method reported by Okamoto and were coated onto an aminopropylated mesoporous spherical silica gel. These final products were used as chiral stationary phases of high performance liquid chromatography for the eighteen structurally related biphenyl conmpounds. The resolution was made using normal-phase methodology with a mobile phase consisting of n-hexane-alcohol (ethanol, 1-propanol, 2-propanol or 1-butanol). The effects of various aliphatic alcohols in the mobile phase were studied. The structural features of the solutes that influence their k'were discussed. A dominant effect of trifluoroaetic acid on chiral separation of aacidicdic solutes was noted.

  5. Carcinogenicity of individual and a mixture of dioxin-like compounds in female Harlan Sprague Dawley rats

    Energy Technology Data Exchange (ETDEWEB)

    Walker, N.; Nyska, A. [National Institute of Environmental Health Sciences, Research Triangle Park, NC (United States); Crockett, P. [Constella Group, Research Triangle Park, NC (US)] (and others)

    2004-09-15

    The human health risk posed by exposure to persistent organochlorine pollutants (POPs), including polychlorinated-dioxins (PCDDs), -furans (PCDFs) and - biphenyls (PCBs), present in the food and the environment is one of widespread concern throughout the industrialized world. The dioxin Toxic Equivalency Factor (TEF) approach is currently the most feasible interim approach for assessing and managing the risk posed by exposure to mixtures of these compounds and has been formally adopted by regulatory bodies in many countries, the International Programme on Chemical Safety and the World Health Organization. The TEF methodology is a relative potency scheme that estimates the total exposure and biological effects of a mixture of chemicals based on a common mechanism of action involving an initial binding of the compound to the Aryl hydrocarbon receptor (AhR). An implicit assumption of the TEF methodology is that the combined risk of effects of the different congeners is dose additive. Therefore, the total dioxin toxic equivalents (TEQs) of a mixture of PCDDs, PCDFs, and PCBs may be estimated by the summation of the mass of each compound in the mixture after adjustment for its potency relative to that of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). While dose additivity is supported for certain mixtures for some biological endpoints in some experimental models, this has never been evaluated for cancer risk. Here we present a summary of four chronic rodent bioassay conducted by the National Toxicology Program (US Department of Health and Human Services) that evaluated the carcinogenicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3.3',4,4',5- pentachlorobiphenyl (PCB126) and 2,3,4,7,8 pentachlorodibenzofuran (PeCDF) and a mixture of these three dioxin-like compounds in female Harlan Sprague Dawley rats. Data from these studies will be used to test the hypothesis of dose-additivity of carcinogenicity by a defined mixture of dioxin-like compounds.

  6. Asphalt rubber mixtures in Portugal: fatigue resistance

    OpenAIRE

    Miranda, Henrique; Batista, Fátima; Neves, José; Antunes, Maria de Lurdes; Fonseca, Paulo

    2009-01-01

    This paper presents a study concerning the fatigue behaviour of asphalt mixtures with bitumen modified with high content of crumb rubber used in Portugal. For assessing the fatigue behaviour of this type of mixtures, four asphalt mixtures with high content of crumb rubber were used: two field bituminous mixtures – an open-graded and a gap-graded – both with granite aggregates; and two laboratory manufactured bituminous mixtures – an open-graded mixture with granite aggregates and a gap-graded...

  7. [Homologues Levels and Distribution Pattern of Polychlorinated Biphenyls in Typical Capacitor Contaminated Soil].

    Science.gov (United States)

    Liu, Jie; Li, Xiao-dong; Zhao, Zhong-hua; Qi, Zhi-fu; Chen, Tong; Yan, Jian-hua

    2015-09-01

    The homologues levels, distribution characteristics and TEQ of 209 PCBs in soil collected around 3 storage sites of PCB-containing wastes were investigated. The PCBs contents and environmental risk were evaluated to provide a scientific basis for site remediation of PCBs contaminated soil. Totally 12 soil samples were collected from 3 PCB-contaminated sites. The analysis results showed that the PCB-concentration in Soil A was 1 705. 0 µg.g-1 ± 424. 3 µg.g-1 (n =4), higher than Soil B (233. 0 µg.g-1 ± 80. 0, n = 4) and Soil C (225. 7 µg.g-1 ± 90. 2 µg.g-1, n = 4), indicating the soil was heavily polluted by PCBs. Trichlorobiphenyl and Tetrachlorobiphenyl dominated the homologues of PCBs. The mass fraction of chlorine in Soil A, Soil B and Soil C was 43. 7% 1. 0%, 45.5% ± 0. 5% and 44.9% ± 0.3%, respectively, which was similar as Aroclor1242 and l#PCB insulating oil. There was an obvious linear correlation between indicator PCBs and total PCBs (R2 = 0. 998), so indicator PCBs can be used to estimate the level of total PCBs. PCB77, PCB105, PCB118 were predominant in doxin-like PCBs, accounting for 89. 5% ± 4. 0% in total. The TEQ levels of the soil samples (in WHO-TEQ) were 3. 56-63. 55 ng.g-1, which demonstrated a high environmental risk in the area. PCB28/31, PCB33/20, PCB66/80, PCB70, PCB32 and PCB18 were the main PCBs isomers. Compared with other results, the local soil was heavily contaminated by PCBs and the surroundings were under a relatively high risk of environmental contamination. PMID:26717710

  8. Binary mixtures of chiral gases

    CERN Document Server

    Presilla, Carlo

    2015-01-01

    A possible solution of the well known paradox of chiral molecules is based on the idea of spontaneous symmetry breaking. At low pressure the molecules are delocalized between the two minima of a given molecular potential while at higher pressure they become localized in one minimum due to the intermolecular dipole-dipole interactions. Evidence for such a phase transition is provided by measurements of the inversion spectrum of ammonia and deuterated ammonia at different pressures. In particular, at pressure greater than a critical value no inversion line is observed. These data are well accounted for by a model previously developed and recently extended to mixtures. In the present paper, we discuss the variation of the critical pressure in binary mixtures as a function of the fractions of the constituents.

  9. Thermal plasmas in gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, A.B. [CSIRO Telecommunications and Industrial Physics, Lindfield, NSW (Australia)

    2001-10-21

    The calculation and measurement of the properties of thermal plasmas in mixtures of different gases are reviewed. The calculation of composition, thermodynamic properties and transport coefficients is described. Particular attention is given to the calculation of diffusion coefficients, which is a significant problem in mixed-gas plasmas. The combined diffusion coefficient formulation is shown to be a useful method for the treatment of diffusion. Computational fluid dynamic modelling of thermal plasmas in gas mixtures is considered, using the examples of demixing in welding arcs, the turbulent mixing of atmospheric air into a plasma jet and a plasma waste destruction process. Diagnostic techniques for mixed-gas plasmas, in particular emission spectroscopy, laser scattering and laser-induced fluorescence, are discussed. (author)

  10. Mixtures of Gaussian process priors

    CERN Document Server

    Lemm, J C

    1999-01-01

    Nonparametric Bayesian approaches based on Gaussian processes have recently become popular in the empirical learning community. They encompass many classical methods of statistics, like Radial Basis Functions or various splines, and are technically convenient because Gaussian integrals can be calculated analytically. Restricting to Gaussian processes, however, forbids for example the implemention of genuine nonconcave priors. Mixtures of Gaussian process priors, on the other hand, allow the flexible implementation of complex and situation specific, also nonconcave "a priori" information. This is essential for tasks with, compared to their complexity, a small number of available training data. The paper concentrates on the formalism for Gaussian regression problems where prior mixture models provide a generalisation of classical quadratic, typically smoothness related, regularisation approaches being more flexible without having a much larger computational complexity.

  11. Weakly faceted cellular patterns versus growth-induced plastic deformation in thin-sample directional solidification of monoclinic biphenyl.

    Science.gov (United States)

    Börzsönyi, Tamás; Akamatsu, Silvère; Faivre, Gabriel

    2009-11-01

    We present an experimental study of thin-sample directional solidification (T-DS) in impure biphenyl. The platelike growth shape of the monoclinic biphenyl crystals includes two low-mobility (001) facets and four high-mobility {110} facets. Upon T-DS, biphenyl plates oriented with (001) facets parallel to the sample plane can exhibit either a strong growth-induced plastic deformation (GID), or deformation-free weakly faceted (WF) growth patterns. We determine the respective conditions of appearance of these phenomena. GID is shown to be a long-range thermal-stress effect, which disappears when the growth front has a cellular structure. An early triggering of the cellular instability allowed us to avoid GID and study the dynamics of WF patterns as a function of the orientation of the crystal.

  12. Polychlorinated biphenyls (PCBs) in the frame of the dismantling of nuclear facilities

    International Nuclear Information System (INIS)

    During construction and maintenance of nuclear facilities PCB (polychlorinated biphenyls) containing paints were used in a large extent in the past. The WAK dismantling and disposal Company has dismantles such facilities and identified the PCB in the buildings. Besides the radionuclides the conventional hazardous material group of the PCBs has also to be disposed. The respective legal regulations have to be considered. In the frame of the contribution the radiological release of building structures with respect to re-use or demolition and residual PCB containing materials is discussed. The radiological disposal in final repositories and the conventional disposal regulations for releasable residual wastes are reported.

  13. Polycyclic aromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCB) in urban soils of Greater London, UK

    OpenAIRE

    Vane, Christopher H.; Kim, Alexander W.; Beriro, Darren J.; Cave, Mark R.; Knights, Katherine; Moss-Hayes, Vicky; Nathanail, Paul C.

    2014-01-01

    Surface soils from a 19 km2 area in east London, UK were analysed for polycyclic aromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCB) (n = 76). ∑16 PAH ranged from 4 to 67 mg/kg (mean, 18 mg/kg) and ∑50 PAH ranged from 6 to 88 mg/kg (mean, 25 mg/kg). ∑7 PCB ranged from 1 to 750 μg/kg (mean, 22 μg/kg) and ∑tri-hepta PCB ranged 9 to 2600 μg/kg (mean, 120 μg/kg). Compared to other international cities concentrations were similar for PAH but higher for PCB. Normal background concentrat...

  14. Whole-Cell Fluorescent Biosensors for Bioavailability and Biodegradation of Polychlorinated Biphenyls

    Directory of Open Access Journals (Sweden)

    David Ryan

    2010-02-01

    Full Text Available Whole-cell microbial biosensors are one of the newest molecular tools used in environmental monitoring. Such biosensors are constructed through fusing a reporter gene such as lux, gfp or lacZ,to a responsive promoter. There have been many reports of the applications of biosensors, particularly their use in assaying pollutant toxicity and bioavailability. This paper reviews the basic concepts behind the construction of whole-cell microbial biosensors for pollutant monitoring, and describes the applications of two such biosensors for detecting the bioavailability and biodegradation of Polychlorinated Biphenyls (PCBs.

  15. trans-Tetraaquabis(nicotinamide-κNcadmium(II biphenyl-4,4′-disulfonate

    Directory of Open Access Journals (Sweden)

    Changlun Shao

    2008-02-01

    Full Text Available In the title compound, [Cd(C6H6N2O2(H2O4](C10H8O6S2, the CdII ion is located on a crystallographic inversion centre. An octahedral coordination geometry is defined by four water molecules in one plane, and two trans N-atom donors of the nicotinamide ligands. The biphenyl-4,4′-disulfonate anion also lies on a crystallographic inversion centre. In the crystal structure, the complex cations are connected to the counter-anions via N—H...O and O—H...O hydrogen bonds, forming a three-dimensional network.

  16. Isolation of bioactive biphenyl compounds from the twigs of Chaenomeles sinensis.

    Science.gov (United States)

    Kim, Chung Sub; Subedi, Lalita; Kwon, Oh Kil; Kim, Sun Yeou; Yeo, Eui-Ju; Choi, Sang Un; Lee, Kang Ro

    2016-01-15

    Investigation of the MeOH extract of Chaenomeles sinensis twigs resulted in the isolation of seven biphenyl compounds (1-7) including a new compound, chaenomin (1). The chemical structures of the isolated compounds were elucidated by extensive NMR data ((1)H and (13)C NMR, (1)H-(1)H COSY, HSQC and HMBC), specific optical rotation, and chemical reaction. Compounds 2 and 6 showed potent cytotoxic activities against four cancer cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15), and compound 7 exhibited potent anti-neuroinflammatory and NGF-potentiating activity. PMID:26706168

  17. Electrodialytic remediation of polychlorinated biphenyls contaminated soil with iron nanoparticles and two different surfactants

    DEFF Research Database (Denmark)

    Gomes, Helena I.; Dias-Ferreira, Celia; Ottosen, Lisbeth M.;

    2014-01-01

    Polychlorinated biphenyls (PCB) are persistent organic pollutants (POP) that strongly adsorb in soils and sediments. There is a need to develop new and cost-effective solutions for the remediation of PCB contaminated soils. The suspended electrodialytic remediation combined with zero valent iron...... nanoparticles (nZVI) could be a competitive alternative to the commonly adapted solutions of incineration or landfilling. Surfactants can enhance the PCB desorption, dechlorination, and the contaminated soil cleanup. In this work, two different surfactants (saponin and Tween 80) were tested to enhance PCB...

  18. Synthesis of new biphenyl-substituted quinoline derivatives, preliminary screening and docking studies

    Indian Academy of Sciences (India)

    Nellisara D Shashikumar; Ganganaika Krishnamurthy; Halehatti S Bhojyanaik; Mayasandra R Lokesh; Kaginalli S Jithendrakumara

    2014-01-01

    New quinoline derivatives containing biphenyl ring were synthesized and characterized by IR, 1H NMR and mass spectral studies. The synthesized compounds were screened for antimicrobial, anthelmintic activities as well as free radical scavenging property against the DPPH radical. The minimum inhibition concentration values showed promising inhibiting activity and are potent biological agents. The compounds showed minimum binding energy towards -tubulin. The compounds 11a, 11c, 13c and 13d have good affinity towards the active pocket and may be considered as a good inhibitor of -tubulin.

  19. Development and characterization of new polyclonal antibodies specific for three polychlorinated biphenyls

    Institute of Scientific and Technical Information of China (English)

    Han Yu Chen; Hui Sheng Zhuang; Chun Zhou

    2009-01-01

    Three polychlorinated biphenyls(PCBs)congeners and their corresponding haptens bearing four carbon length carboxylic groups that can be linked to a protein for raising antibodies were synthesized.The three resultant immunogens were fabricated and used to stimulate immune responses in rabbits to survey the characteristics of the haptens.Three of the resultant polyclonal antibodies(Pabs)were obtained.The antiserum exhibited relatively high antibody titres(1:32-64)in double agar diffusion.◎2008 Hui Sheng Zhuang.Published by Elsevier B.V.on behalf of Chinese Chemical Society.All rights reserved.

  20. Electrochemical and optical properties of biphenyl bridged-dicarbazole oligomer films: Electropolymerization and electrochromism

    Energy Technology Data Exchange (ETDEWEB)

    Koyuncu, Sermet [Department of Chemistry, Faculty of Sciences and Arts, Canakkale Onsekiz Mart University, 17020 Canakkale (Turkey); Can Vocational School, Canakkale Onsekiz Mart University, 17400 Canakkale (Turkey)], E-mail: sermetkoyuncu@hotmail.com; Gultekin, Burak [Solar Energy Institute, Ege University, 35100 Bornova, Izmir (Turkey); Zafer, Ceylan [Solar Energy Institute, Ege University, 35100 Bornova, Izmir (Turkey)], E-mail: ceylan.zafer@ege.edu.tr; Bilgili, Hakan; Can, Mustafa; Demic, Serafettin [Solar Energy Institute, Ege University, 35100 Bornova, Izmir (Turkey); Kaya, Ismet [Department of Chemistry, Faculty of Sciences and Arts, Canakkale Onsekiz Mart University, 17020 Canakkale (Turkey); Icli, Siddik [Solar Energy Institute, Ege University, 35100 Bornova, Izmir (Turkey)

    2009-10-01

    4,4'-Di(N-carbazoyl)biphenyl monomer (CBP) was synthesized and coated onto ITO-glass surface by electrochemical oxidative polymerization. Its CV shows two distinct one-electron and stepwise oxidation processes occurred at 1.29 and 1.61 V. By using this property, the monomer was electrochemically polymerized separately at these oxidation states and thus, two different oligomer films were obtained afterwards. Their spectro-electrochemical and electrochromic properties were also investigated. Switching ability of the oligomers was evaluated by kinetic studies upon measuring the percent transmittance (%T) at their maximum contrast point, indicating that these oligomers were found to be suitable material for electrochromic devices.

  1. Biodegradation of biphenyl and removal of 2-chlorobiphenyl by Pseudomonas sp. KM-04 isolated from PCBs-contaminated mine impacted soil

    Science.gov (United States)

    Nam, I.; Chon, C.; Kim, J.; Kim, Y.

    2013-12-01

    The aim of the present study is to remediate the PCBs contaminated mine soil using microcosm study. For that, the naturally occurring microorganisms are stimulated and enriched in soil itself by supplementing biphenyl as well as benzoic acid. As a result the biphenyl degrading organisms are induced to degrade the PCBs contamination. From the stimulated soil, the biphenyl degrading organisms are isolated and degraded metabolites are elucidated. Pseudomonas sp. strain KM-04 was isolated from PCBs-contaminated soil in a coal mine-impacted area, and identification of bacteria was done by sequencing the 16S rRNA gene analysis. The growth of Pseudomonas sp. strain KM-04 using biphenyl as the sole carbon source was investigated by culturing in 100-mL Erlenmeyer flasks containing 10 ml sterilized MSM and 10 μg/ml biphenyl, and the ability of KM-04 to remove biphenyl and 2-chlorobiphenyl from mine soil was investigated. Metabolite formation was confirmed by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometric analysis. Pseudomonas sp. strain KM-04 uses biphenyl as a sole carbon and energy source, and resting cells convert biphenyl to its metabolic intermediates, including dihydroxybiphenyl, 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid, and benzoic acid. Incubation of real soil collected from abandoned mine areas with resting cells of Pseudomonas sp. strain KM-04 for 10 days resulted in the 98.5 % of biphenyl and 82.3 % of 2-chlorobiphenyl in a slurry system. The ability of the Pseudomonas sp. strain KM-04 to bioremediate biphenyl and 2-chlorobiphenyl from abandoned mine soil was examined using soil microcosm studies under laboratory conditions. Treatment of mine soil with the Pseudomonas sp. strain KM-04 for 15 days resulted in 87.1 % reduction in biphenyl and 68.7 % in 2-chlorobiphenyl contents. The results suggest that Pseudomonas sp. strain KM-04 is a potential candidate for the biological removal of biphenyl and chlorinated derivatives

  2. PARTICLE SEGREGATION IN FLUIDIZED BINARY-MIXTURES

    NARCIS (Netherlands)

    HOFFMANN, AC; JANSSEN, LPBM

    1993-01-01

    The particle segregation in fluidised beds consisting of different types of binary mixtures is shown to be governed by the same particle transport processes. The segregation behaviour of both ''different-density mixtures'' and ''equal-density mixtures'', two types of system which until now largely h

  3. Psychophysical studies of mixtures of tastants.

    NARCIS (Netherlands)

    Graaf, de C.

    1988-01-01

    The human perception of mixtures of tastante was studied with reference to three central issues, i.e., 1) the paradigma of equiratio taste substance mixtures. as an instrument to manipulate the physical composition of tastant mixtures. This paradiama also enables the construction of psychophysical f

  4. Some properties of explosive mixtures containing peroxides

    International Nuclear Information System (INIS)

    This study concerns mixtures of triacetone triperoxide (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane, TATP) and ammonium nitrate (AN) with added water (W), as the case may be, and dry mixtures of TATP with urea nitrate (UN). Relative performances (RP) of the mixtures and their individual components, relative to TNT, were determined by means of ballistic mortar. The detonation energies, E0, and detonation velocities, D, were calculated for the mixtures studied by means of the thermodynamic code CHEETAH. Relationships have been found and are discussed between the RP and the E0 values related to unit volume of gaseous products of detonation of these mixtures. These relationships together with those between RP and oxygen balance values of the mixtures studied indicate different types of participation of AN and UN in the explosive decomposition of the respective mixtures. Dry TATP/UN mixtures exhibit lower RP than analogous mixtures TATP/AN containing up to 25% of water. Depending on the water content, the TATP/AN mixtures possess higher detonability values than the ANFO explosives. A semi-logarithmic relationship between the D values and oxygen coefficients has been derived for all the mixtures studied at the charge density of 1000 kg m-3. Among the mixtures studied, this relationship distinguishes several samples of the type of 'tertiary explosives' as well as samples that approach 'high explosives' in their performances and detonation velocities

  5. Polychlorinated biphenyls (PCBs) in a benthic ecosystem in Gwangyang Bay, South Korea

    International Nuclear Information System (INIS)

    Highlights: ► PCBs are still detectable in Gwangyang Bay in spite of their ban in 1980s. ► PCBs in the benthic ecosystem is enriched in lower chlorinated biphenyls. ► PCBs are released from a nearby local steel industry. ► Distribution of PCBs to the bay arises mostly from atmospheric transfer. - Abstract: Benthic ecosystem in Gwangyang Bay, a fast developing industrial area with steel production, port container handling, petroleum and other chemical processing in South Korea was studied. The average levels of polychlorinated biphenyls (ΣPCB) in the benthic components were: seawater 2.99 ± 0.13 (ng/L); sediment 294 ± 118 (ng/g TOC); [biota = ng/g lipid] starfish 92; prawn 131 ± 2; mussels 127 ± 22; crab 182 ± 114; clam 187; polychaeta 215; sea cucumber 497 ± 90; squill 603 ± 38; fish 396 ± 159. Levels in the inner bay samples were higher than the outer bay samples suggesting land based pollution. Good correlation (r2 = 0.79; p < 0.05) existed between PCB concentration and lipid content indicating partitioning processes in action. PCB signature in the abiotic and biotic components shows enrichment of lower chlorinated congeners emitted by a unique source nearby, viz. steel manufacturing plant.

  6. Tissue damage after acute intoxication by polychlorinated biphenyls (PCBs in cockroaches Blattella germanica

    Directory of Open Access Journals (Sweden)

    S Lambiase

    2009-06-01

    Full Text Available It is common knowledge that polychlorinated biphenyls (PCBs represent a serious threat to the health of both vertebrates and invertebrates. As far as the former are concerned, especially as regards human beings, a broad literature describes the direct and indirect effects induced by the PCBs on their systems and organs. Among invertebrates, the information available is mostly related to arthropods and is, however, very scarce. The aim of this work was to evaluate the effects of polychlorinated biphenyls (PCBs on tissues and organs of individuals belonging to a species of Blattaria (Blattella germanica treated with various doses of this toxic material. The pathologies found became more serious as the dosage increased and were present throughout the entire digestive system, in the fat body and in the male gonads: in these areas cell and tissue breakdown and severely damaged spermiogenesis were observed. In particular, the testicles, Malpighian tubules and fat body accumulated an amorphous basophilic PAS-positive substance. Furthermore, the NOS-dependent NADPH diaphorase activity pattern in the retina and optic lobes was more evident in the treated than in the control insects.

  7. Hydroxy and methylsulfone metabolites of polychlorinated biphenyls in the human blood and tissues

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Yoshito; Haraguchi, Koichi [Daiichi College of Pharmaceutical Sciences, Fukuoka (Japan)

    2004-09-15

    Polychlorinated biphenyls (PCBs) are a group of chlorinated compounds which have polluted the global environment, persistently retained in wildlife and humans, and eventually affected the human health. PCBs are biotransformed to mainly hydroxy (HO-) and methylsulfone (MeSO{sub 2}-) metabolites in the animal and human tissues. About ten thousands of chemical and biological researches on PCBs, HOPCBs and MeSO{sub 2}-PCBs have been reported and reviewed so far. Letcher et al. cleverly reviewed the HO-PCBs and MeSO2-PCBs in 2000. We review the contamination of HO-PCBs and MeSO{sub 2}-PCBs in human tissues and their possible effects to human health. Different positional numberings of Cl-, HO- and MeSO{sub 2}- on biphenyl rings were used by different authors. Then, nomenclature of PCB metabolite was assessed by Maervoet et al. and they suggested to use the IUPAC chemical name and number of parent PCB congener with the subsequent assignment of the phenyl ring position number of the HO- or MeSO{sub 2}- substituent number afterward.

  8. The associations between the environmental exposure to polychlorinated biphenyls (PCBs) and breast cancer risk and progression

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Polychlorinated biphenyls(PCBs) are chlorinated biphenyl compounds with wide applications in the industry.In spite of a ban on their production in the late 1970s,PCBs,as a group of POPs,are still persistent and widely spread in the environment,posing potential threats to human health.The role of PCBs as etiologic agents for breast cancer has been intensively explored in a variety of in vivo,animal and epidemiologic studies.Initial investigations indicated higher levels of PCBs in mammary tissues or sera corresponded to the occurrence of breast cancer,but later studies showed no positive association between PCB exposure and breast cancer development.More recent data suggested that the CYP1A1 m2 polymorphisms might add increased risk to the etiology of breast cancer in women with environmental exposure to PCBs.PCBs are implicated in advancing breast cancer progression,and our unpublished data reveals that PCBs activate the ROCK signaling to enhance breast cancer metastasis.Therefore,the correlation between PCB exposure and breast cancer risk warrants further careful investigations.

  9. Syntheses,Crystal Structures and Fluorescence Properties of Two Triazolyl Derivatives with Biphenyl Links

    Institute of Scientific and Technical Information of China (English)

    LING Yun; LI Jing; HU Ai-Xi; ZHANG Lei

    2009-01-01

    Two novel triazolyl derivatives with biphenyl links,namely 4,4-bis(1,2,4-triazol-1-yl-methyl)biphenylene 1 and 4,4-bis(3,5-dimethyl-1,2,4-triazol-1-ylmethyl)biphenylene 2,have been synthesized and structurally characterized by single-crystal X-ray diffraction.Compounds 1·H2O·HCl and 2·2H2O·2HCl crystallize in the monoclinic system with spacegroup C2/c and P21/c,respectively.he dihedral angles of the two phenyl rings are 30.26(6)° in 1·H2O·HCl,while co-planar(0.00(7)°)in 2·2H2O·2HCl.In 1'H2O·HCl,the N-H…O hydrogen bonds link 1 to form chain-like structures which are further connected by O-H…Cl,C-H…Cl,C-H…O and π-π supramolecular interactions.The hydrogen bonds of O-H…Cl in 2·2H2O·2HCl provide distinguishing P/M helical chains along the baxis,and these chains are further connected by N-H…O hydrogen bonds to generate a 2D structure.Compounds 1 and 2 in methanol solution show much stronger emission bands at 319 nm than biphenyl at 3 16 nm under excitation at 260 nm.

  10. Occurrence and congeners specific of polychlorinated biphenyls in agricultural soils from Southern Jiangsu, China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-ying; QIU Li-min; HE Jia; LIAO Yuan; LUO Yong-ming

    2007-01-01

    A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls(PCBs)in order to assess the levels of pollution,sources,area distribution,and potential risk for the environment.All methods were rigorously tested and an adequate quality control was ensured.Only one site had no PCBs residues,and the highest total PCBs concentration in the surface soils was 32.83 ng/g.The average concentration in all the soil samples was 4.13ng/g.signaling low-level pollution.Tetra-,penta-,and hexa-chlorinated biphenyls were dominant speoes in soil samples,accounnng for more than 75%of ΣPCBs in the soil samples.PCB118 was the most abundant congener in all the samples.The PCB118 Was about 20%of ΣPCBs.The soil organic matter content showed only a weak correlation with the levels of all PCB congeners,in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues.To a certain extent,the sources and land use seemed to influence the levels of PCBs.

  11. Ab initio study of long-range electron transfer between biphenyl anion radical and naphthalene

    Institute of Scientific and Technical Information of China (English)

    李象远; 肖顺清; 何福城

    1999-01-01

    After the separation of the donor, the aeceptor, and the σ-type bridge from the π-σ-π system, the geometries of biphenyl, biphenyl anion radical, naphthalene, and naphthalene anion radical are optimized, and then the reorganization energy for the intermolecular electron transfer (ET) at the levels of HF/4-31G and HF/DZP is calculated. The ET matrix elements of the self-exchange reactions of the π-σ-π systems have been calculated by means of both the direct calculation based on the variational principle, and the transition energy between the molecular orbitals at the linear coordinate R=0.5. For the cross reactions, the ET matrix element and the geometry of the transition state are determined by searching the minimum energy splitting △min along the reaction coordinate. In the evaluation of the solvent reorganization energy of the ET in solution, the Marcus’ two-sphere model has been invoked. A few of ET rate constants for the intramolecular ET reactions for the π-σ-π systems, which contain

  12. The proton nuclear magnetic shielding tensors in biphenyl: experiment and theory.

    Science.gov (United States)

    Schönborn, Frank; Schmitt, Heike; Zimmermann, Herbert; Haeberlen, Ulrich; Corminboeuf, Clémence; Grossmann, Gisbert; Heine, Thomas

    2005-07-01

    Line-narrowing multiple pulse techniques are applied to a spherical sample crystal of biphenyl. The 10 different proton shielding tensors in this compound are determined. The accuracy level for the tensor components is 0.3 ppm. The assignment of the measured tensors to the corresponding proton sites is given careful attention. Intermolecular shielding contributions are calculated by the induced magnetic point dipole model with empirical atom and bond susceptibilities (distant neighbours) and by a new quantum chemical method (near neighbours). Subtracting the intermolecular contributions from the (correctly assigned) measured shielding tensors leads to isolated-molecule shielding tensors for which there are symmetry relations. Compliance to these relations is the criterion for the correct assignment. The success of this program indicates that intermolecular proton shielding contributions can be calculated to better than 0.5 ppm. The isolated-molecule shielding tensors obtained from experiment and calculated intermolecular contributions are compared with isolated-molecule quantum chemical results. Expressed in the icosahedral tensor representation, the rms differences of the respective tensor components are below 0.5 ppm for all proton sites in biphenyl. In the isolated molecule, the least shielded direction of all protons is the perpendicular to the molecular plane. For the para proton, the intermediate principal direction is along the C-H bond. It is argued that these relations also hold for the protons in the isolated benzene molecule. PMID:15949748

  13. Assessing atmospheric concentration of polychlorinated biphenyls by evergreen Rhododendron maximum next to a contaminated stream.

    Science.gov (United States)

    Dang, Viet D; Walters, David M; Lee, Cindy M

    2016-09-01

    Conifers are often used as an air passive sampler, but few studies have focused on the implication of broadleaf evergreens to monitor atmospheric semivolatile organic compounds such as polychlorinated biphenyls (PCBs). In the present study, the authors used Rhododendron maximum (rhododendron) growing next to a contaminated stream to assess atmospheric PCB concentrations. The present study area was located in a rural setting and approximately 2 km downstream of a former capacitor plant. Leaves from the same mature shrubs were collected in late fall 2010 and winter and spring 2011. Polychlorinated biphenyls were detected in the collected leaves, suggesting that rhododendron can be used as air passive samplers in rural areas where active sampling is impractical. Estimated ΣPCB (47 congeners) concentrations in the atmosphere decreased from fall 2010 to spring 2011 with concentration means at 3990 pg m(-3) , 2850 pg m(-3) , and 931 pg m(-3) in fall 2010, winter 2011, and spring 2011, respectively. These results indicate that the atmospheric concentrations at this location continue to be high despite termination of active discharge from the former industrial source. Leaves had a consistent pattern of high concentrations of tetra-CBs and penta-CBs similar to the congener distribution in polyethylene passive samplers deployed in the water column, suggesting that volatilized PCBs from the stream were the primary source of contaminants in rhododendron leaves. Environ Toxicol Chem 2016;35:2192-2198. © 2016 SETAC. PMID:26889751

  14. Assessment of exposure risk of polychlorinated biphenyls to interior least terns (Sterna antillarum).

    Science.gov (United States)

    Sanchez, Brian C; Caldwell, Colleen A

    2008-03-01

    Risk of polychlorinated biphenyl (PCB) exposure and effects were assessed for a colony of federally endangered interior least terns (Sterna antillarum) nesting on the Bitter Lake National Wildlife Refuge (NM, USA). The colony feeds from an area on the Refuge (Hunter Marsh/Oxbow Complex) wherein fish with elevated concentrations of total PCBs have been documented. Concentrations of total PCBs in whole fish averaged 0.94 mg/kg with a maximum concentration of 2.77 mg/kg, wet weight. Estimated daily PCB intake rates by adult birds throughout their 180-d breeding season ranged from <0.01 mg/kg/d to 0.98 mg/ kg/d, yielding hazard quotients that ranged from 0.01 to 21.68. Polychlorinated biphenyls pose a moderate risk to the colony of interior least terns that breed at the Bitter Lake National Wildlife Refuge, but the exposure rate is not likely to threaten their overall breeding success. PMID:17967068

  15. Transcriptional Response of Rhodococcus aetherivorans I24 to Polychlorinated Biphenyl-Contaminated Sediments

    KAUST Repository

    Puglisi, Edoardo

    2010-04-06

    We used a microarray targeting 3,524 genes to assess the transcriptional response of the actinomycete Rhodococcus aetherivorans I24 in minimal medium supplemented with various substrates (e. g., PCBs) and in both PCB-contaminated and non-contaminated sediment slurries. Relative to the reference condition (minimal medium supplemented with glucose), 408 genes were upregulated in the various treatments. In medium and in sediment, PCBs elicited the upregulation of a common set of 100 genes, including gene-encoding chaperones (groEL), a superoxide dismutase (sodA), alkyl hydroperoxide reductase protein C (ahpC), and a catalase/peroxidase (katG). Analysis of the R. aetherivorans I24 genome sequence identified orthologs of many of the genes in the canonical biphenyl pathway, but very few of these genes were upregulated in response to PCBs or biphenyl. This study is one of the first to use microarrays to assess the transcriptional response of a soil bacterium to a pollutant under conditions that more closely resemble the natural environment. Our results indicate that the transcriptional response of R. aetherivorans I24 to PCBs, in both medium and sediment, is primarily directed towards reducing oxidative stress, rather than catabolism. © 2010 Springer Science+Business Media, LLC.

  16. Investigations of reversible thermochromic mixtures

    Science.gov (United States)

    MacLaren, Douglas C.

    Three-component organic thermochromic systems have potential applications in reversible, rewritable thermal printing. In principle, such mixtures could maintain a coloured or non-coloured state at ambient temperature depending on their thermal treatment. These systems generally consist of a functional dye (1--3 mol%), a weakly acidic colour developer (5--25 mol%), and a high-melting organic solvent (75--90 mol%). Colour development occurs at the fusion temperature of the mixture, which triggers the interaction of the dye and developer. Slow cooling of the melt results in an equilibrium state with low colour density, whereas rapid cooling of the melt results in a metastable state with high colour density. The metastable state can be decoloured by heating to an intermediate decolourisation temperature at which the coloured state becomes unstable. Barriers to the widespread use of reversible, rewritable thermochromic materials include problems with colour contrast, colour stability, and decolourisation rates. Development is hindered by a lack of detailed knowledge of the interactions between components in these systems. In this study the developer-dye and developer-solvent interactions were examined for an archetypal dye/developer/solvent thermochromic system. Vibrational spectroscopy, NMR, and thermal analysis were used to examine compounds formed in developer/dye and developer/solvent binary mixtures. Rewritable thermochromic properties such as metastable colour density, equilibrium colour density, and decolourisation rates were examined and discussed in terms of the thermodynamics of the developer/dye and developer/solvent interactions. Observed thermochromic properties are shown to be strongly correlated to a competition between the dye and the solvent for interaction with the developer. Increasing the attractive interaction between the solvent and developer results in enhanced rewritable thermochromic properties.

  17. GRAVITY PIPELINE TRANSPORT FOR HARDENING FILLING MIXTURES

    Directory of Open Access Journals (Sweden)

    Leonid KROUPNIK

    2015-12-01

    Full Text Available In underground mining of solid minerals becoming increasingly common development system with stowing hardening mixtures. In this case the natural ore array after it is replaced by an artificial excavation of solidified filling mixture consisting of binder, aggregates and water. Such a mixture is prepared on the surface on special stowing complexes and transported underground at special stowing pipelines. However, it is transported to the horizons of a few kilometers, which requires a sustainable mode of motion of such a mixture in the pipeline. Hardening stowing mixture changes its rheological characteristics over time, which complicates the calculation of the parameters of pipeline transportation. The article suggests a method of determining the initial parameters of such mixtures: the status coefficient, indicator of transportability, coefficient of hydrodynamic resistance to motion of the mixture. These indicators characterize the mixture in terms of the possibility to transport it through pipes. On the basis of these indicators is proposed methodology for calculating the parameters of pipeline transport hardening filling mixtures in drift mode when traffic on the horizontal part of the mixture under pressure column of the mixture in the vertical part of the backfill of the pipeline. This technique allows stable operation is guaranteed to provide pipeline transportation.

  18. Interpreting Y chromosome STR haplotype mixture.

    Science.gov (United States)

    Ge, Jianye; Budowle, Bruce; Chakraborty, Ranajit

    2010-05-01

    Mixture interpretation is a challenging problem in forensic DNA analyses. The interpretation of Y short tandem repeat (STR) haplotype mixtures, due to a lack of recombination, differs somewhat from that of the autosomal DNA markers and is more complex. We describe approaches for calculating the probability of exclusion (PE) and likelihood ratio (LR) methods to interpret Y-STR mixture evidence with population substructure incorporated. For a mixture sample, first, all possible contributor haplotypes in a reference database are listed as a candidate list. The PE is the complement of the summation of the frequencies of haplotypes in the candidate list. The LR method compares the probabilities of the evidence given alternative hypotheses. The hypotheses are possible explanations for the mixture. Population substructure may be further incorporated in likelihood calculation. The maximum number of contributors is based on the candidate list and the computing complexity is polynomial. Additionally, mixtures were simulated by combining two or three 16 Y-STR marker haplotypes derived from the US forensic Y-STR database. The average PE was related to the size of database. With a database comprised of 500 haplotypes an average PE value of at least 0.995 can be obtained for two-person mixtures. The PE decreases with an increasing number of contributors to the mixture. Using the total sample population, the average number of candidate haplotypes of two-person mixtures is 3.73 and 95% mixtures have less than or equal to 10 candidate haplotypes. More than 98.7% of two-person mixtures can only be explained by the haplotype combinations that mixtures are composed. These values are generally higher for three-person mixtures. A small proportion of three-person mixture can also be explained by only two haplotypes.

  19. Optimizing Laboratory Mixture Design as It Relates to Field Compaction to Improve Asphalt Mixture Durability

    OpenAIRE

    Hekmatfar, Ali; McDaniel, Rebecca S; Shah, Ayesha; Haddock, John E.

    2015-01-01

    Most departments of transportation, including Indiana, currently use the Superpave mixture design method to design asphalt mixtures. This method specifies that the optimum asphalt content for a given gradation be selected at 4 percent air voids. During construction, these mixtures are typically compacted to 7-8 percent air voids. If mixtures were designed to be more compactable in the field they could be compacted to the same density as the laboratory mixture design, which would increase pave...

  20. Polychlorinated biphenyls (PCBs) in indoor air originating from sealants in contaminated and uncontaminated apartments within the same housing estate

    DEFF Research Database (Denmark)

    Frederiksen, Marie; Meyer, Harald William; Ebbehøj, Niels Erik;

    2012-01-01

    Twenty-four congeners of polychlorinated biphenyls (PCBs) were measured in 83 air samples and 20 elastic sealants samples of apartments with PCB-containing sealants. In addition, PCBs were measured in 21 air samples from reference apartments located in an uncontaminated section of the same estate...

  1. Levels of Polychlorinated Dibenzo-p-Dibenzofurans, and Biphenyls in Southern Mississippi Catfish and Estimation of Potential.

    Science.gov (United States)

    Fish consumption has been classified as one of the primary pathways of exposure to polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and biphenyls (PCBs). In this study, we evaluated tissue levels of the 17 laterally-substituted PCDD/Fs, 12 dioxin-like PCBs, and 97 non-...

  2. The Relationship between Prenatal and Postnatal Exposure to Polychlorinated Biphenyls (PCBs) and Cognitive, Neuropsychological, and Behavioral Deficits: A Critical Appraisal

    Science.gov (United States)

    Cicchetti, Domenic V.; Kaufman, Alan S.; Sparrow, Sara S.

    2004-01-01

    Our purpose in this report is to evaluate scientifically that body of literature relating the effects of prenatal and postnatal exposure to polychlorinated biphenyls (PCBs) upon neurobehavioral, health-related, and cognitive deficits in neonates, developing infants, children, and adults. The data derive from seven cohorts: six cohorts of mothers…

  3. Environmental exposure to polychlorinated biphenyls (PCBs) and dioxins - Consequences for longterm neurological and cognitive development of the child. A Review

    NARCIS (Netherlands)

    Boersma, ER

    2001-01-01

    Polychlorinated biphenyl's (PCBs) and dioxins are environmental pollutants. Calculated on a body weight basis, prenatally as well as postnatally through breast-feeding, large amounts are transferred from mother to the child. Formula is free of these substances. Considering their potential developmen

  4. (Biphenyl-2-yl)bromidobis(2-methyl­tetra­hydro­furan-κO)magnesium(II)

    OpenAIRE

    Michael Bolte; D. Wohlgemuth; Simon Nordschild

    2009-01-01

    In the title Grignard reagent, [MgBr(C12H9)(C5H10O)2], the Mg centre adopts a distorted tetrahedral MgCO2Br arrangement. The dihedral angle between the two aromatic rings of the biphenyl residue is 44.00 (14)°. Each molecule incorporates one R- and one S-configured 2-methyltetrahydrofuran molecule.

  5. USE OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

    Science.gov (United States)

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ...

  6. USE OF PLANT AND EARTHWORM BIOASSYS TO EVALUATE REMEDIATION OF SOIL FROM A SITE CONTAMINATED WITH POLYCHLORINATED BIPHENYLS

    Science.gov (United States)

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction tehnology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The ear...

  7. ASSESSMENT OF PCDDS (POLYCHLORINATED DIBENZODIOXINS) AND PCDFS (POLYCHLORINATED DIBENZOFURANS) FROM PCB (POLYCHLORINATED BIPHENYL'S) TRANSFORMER AND CAPACITOR FIRES

    Science.gov (United States)

    The EPA, under the Toxic Substances Control Act, has been mandated to develop appropriate regulations for the control of exposure to polychlorinated biphenyls (PCBs). In light of this responsibility the EPA Office of Toxic Substances recently issued an Advance Notice of Proposed ...

  8. Nanosecond photochromic molecular switching of a biphenyl-bridged imidazole dimer revealed by wide range transient absorption spectroscopy

    NARCIS (Netherlands)

    T. Yamaguchi; M.F. Hilbers; P.P. Reinders; Y. Kobayashi; A.M. Brouwer; J. Abe

    2015-01-01

    We demonstrate that a biphenyl-bridged imidazole dimer exhibits fast photochromism with a thermal recovery time constant of similar to 100 ns, which is the fastest thermal back reaction in all reported imidazole dimers. Sub-ps transient absorption spectroscopy reveals that the generation process of

  9. Kinetics and conductivity parameters of uptake and transport of polychlorinated biphenyls in the Caco-2 intestinal cell line model

    NARCIS (Netherlands)

    Dulfer, W.J.; Govers, H.A.J.; Groten, J.P.

    1998-01-01

    Most of the accumulation of polychlorinated biphenyls (PCBs) over the food chain can be attributed to contaminant uptake from food. The effect of fatty acid absorption on net uptake and transport fluxes of a selection of 14 PCBs over the organismal gut epithelium has been determined in monolayers of

  10. Impact of polychlorinated biphenyl and polycyclic aromatic hydrocarbon sequestration in sediment on bioaccumulation in aquatic food webs

    NARCIS (Netherlands)

    Moermond, C.T.A.; Roessink, I.; Jonker, M.T.O.; Meijer, T.; Koelmans, A.A.

    2007-01-01

    It is not clear whether sequestration or aging of organic chemicals like polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) limits accumulation in higher levels of aquatic food chains. Therefore, the effect of aging on accumulation was studied in 1-m3 model ecosystems that

  11. Photochemistry treatment of polychlorinated biphenyls (PCB) in dielectric fluid; Tratamiento fotoquimico de bifenilos policlorados en fluidos dielectricos

    Energy Technology Data Exchange (ETDEWEB)

    Manzano Quinones, M. A. [Escuela Politecnica Superior de Algeciras (Spain)

    2000-07-01

    In this work a study of polychlorinated biphenyls (PCB) photodegradation in dielectric fluid have been done. The experiments has been carried out in a pilot scale photo rector with an ultraviolet light source. The results obtained showed a 92% elimination of PCB following a first kinetic order. In addition the photo reaction products have been identified. (Author) 6 refs.

  12. Effects of environmental exposure to polychlorinated biphenyls and dioxins on cognitive abilities in Dutch children at 42 months of age

    NARCIS (Netherlands)

    Patandin, S; Lanting, Caren; Mulder, PGH; Boersma, ER; Sauer, PJJ; Weisglas-Kuperus, N

    1999-01-01

    Objective: To study possible adverse effects of environmental exposure to polychlorinated biphenyls (PCB) and dioxins on cognitive functioning in young children. Methods: In a follow-up of the Dutch PCB/Dioxin study, cognitive abilities were assessed with the Kaufman Assessment Battery for Children

  13. Plasma polychlorinated biphenyl levels in Dutch preschool children either breast-fed or formula-fed during infancy

    NARCIS (Netherlands)

    Patandin, S; WeisglasKuperus, N; deRidder, MAJ; KoopmanEsseboom, C; vanStaveren, WA; vanderPaauw, CG; Sauer, PJJ

    1997-01-01

    Objectives. This study examined the influence of lactational and in utero exposure to polychlorinated biphenyls (PCBs) on plasma PCB levels in children. Methods. Plasma PCB levels were measured in 173 children at 3.5 years, of whom 91 were breast-fed and 82 were formula-fed in infancy. Results. Medi

  14. First worldwide UNEP interlaboratory study on persistent organic pollutants (POPs) with data on polychlorinated biphenyls and organochlorine pesticides

    NARCIS (Netherlands)

    Leeuwen, van S.P.J.; Bavel, van B.; Boer, de J.

    2013-01-01

    The first worldwide interlaboratory study on persistent organic pollutants (POPs) under the Stockholm Convention was organized, with a participation of 103 laboratories from Asia, Europe, the Americas, Africa and Australia, of which the majority submitted data on polychlorinated biphenyls (PCBs) and

  15. Effect of Quercetin on Haematobiochemical and Histological Changes in the Liver of Polychlorined Biphenyls-Induced Adult Male Wistar Rats

    OpenAIRE

    Kandaswamy Selvakumar; Senthamilselvan Bavithra; Sekaran Suganya; Firdous Ahmad Bhat; Gunasekaran Krishnamoorthy; Jagadeesan Arunakaran

    2013-01-01

    Polychlorinated biphenyls exposure damages the rat liver cells. Hematological parameters such as hemoglobin, packed cell volume, red-blood cells, white-blood cells, neutrophils, platelet counts, and RBC indices were significantly decreased. Polymorphs, eosinophil counts, and erythrocyte sedimentation rate were significantly increased. Serum liver enzymes such as aspartate transaminase, alanine transaminase, alkaline phosphatase, and gamma-glutamyl transferase were increased by PCBs treatment....

  16. Determination of in vitro relative potency (REP) values for mono-ortho polychlorinated biphenyls after purification with active charcoal

    NARCIS (Netherlands)

    Peters, A.K.; Leonards, P.E.G.; Zhao, B.; Bergman, A.; Denison, M.S.; Berg, van den M.

    2006-01-01

    The TEF system for dioxin-like compounds has included assignment of TEF values for mono-ortho polychlorinated biphenyls (MO-PCBs). Small traces of aryl hydrocarbon receptor (AhR)-active impurities could result in artifactually higher relative potency (REP) values. MO-PCBs -105, -118, -156, and -167

  17. Polychlorinated biphenyls, glycaemia and diabetes in a population living in a highly polychlorinated biphenyls-polluted area in northern Italy: a cross-sectional and cohort study

    Directory of Open Access Journals (Sweden)

    Claudia Zani

    2013-05-01

    Full Text Available Background. Polychlorinated biphenyls (PCBs have been found to be associated with diabetes in some, but not all, studies performed so far. The aim of this study was to assess the association between PCB serum levels and glycaemia and diabetes in people living in Brescia, a highly industrialised PCB-polluted town in Northern Italy. Design and Methods. 527 subjects were enrolled in a cross-sectional population-based study: they were interviewed face-to-face in 2003 and also provided a blood sample under fasting conditions. The concentration of 24 PCB congeners was determined using gas-chromatography (GC/MS. Subsequently, all subjects were included in a follow-up (cohort study. According to the Local Health Authority health-care database, subjects were considered to be diabetic if they had diabetes at interview time (prevalent cases or during a 7-year follow-up (incident cases. Results. A total of 53 subjects (10.0% were diabetics: 28 had dia- betes at enrolment and other 25 developed the disease subsequently. Diabetes frequency increased according to the serum concentrations of total PCBs and single PCB congeners, but no association was found when estimates were adjusted for education, body mass index, age and gender by logistic regression analysis. Accordingly, glycaemia increased with PCB serum levels, but no association was observed when multiple regression analysis, including confounding factors, was performed. Conclusions. This study does not support the hypothesis that PCB environmental exposure is strictly associated with diabetes or glycaemia.

  18. Natural mixtures of persistent organic pollutants (POPs) suppress ovarian follicle development, liver vitellogenin immunostaining and hepatocyte proliferation in female zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Kraugerud, Marianne, E-mail: Marianne.Kraugerud@nvh.no [Dept. of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Doughty, Richard William, E-mail: vetrwdoughty@yahoo.co.uk [Sundveien 22, 2015 Leirsund (Norway); Lyche, Jan L., E-mail: Jan.Lyche@nvh.no [Dept. of Food Safety and Infection Biology, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Berg, Vidar, E-mail: Vidar.Berg@nvh.no [Dept. of Food Safety and Infection Biology, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Tremoen, Nina H., E-mail: Nina.Hardnes@nvh.no [Dept. of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Alestrom, Peter, E-mail: Peter.Alestrom@nvh.no [Dept. of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Aleksandersen, Mona, E-mail: Mona.Aleksandersen@nvh.no [Dept. of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway); Ropstad, Erik, E-mail: Erik.Ropstad@nvh.no [Dept. of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, POB 8146 Dep., 0033 Oslo (Norway)

    2012-07-15

    Persistent organic pollutants such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and dichlorodiphenyltrichloroethane (DDT) are present in high concentrations in livers of burbot (Lota lota) in Lake Mjosa, Norway. In order to assess effects of such pollutants on fish gonadal morphology, female zebrafish were exposed in two generations by food to mixtures of pollutants extracted from livers of burbot from Lake Mjosa (high and low dose) and Lake Losna, which represents background pollution, and compared to a control group. Ovarian follicle counts detected a significant decrease in late vitellogenic follicle stages in fish exposed to the Losna and the high concentrations of Mjosa mixtures in fish from the first generation. In addition, proliferation of granulosa cells, visualized by immunohistochemistry against proliferating cell nuclear antigen (PCNA), was decreased in all exposure groups in either early or late vitellogenic follicle stages compared to control. This was accompanied by increased apoptosis of granulosa cells. There was a decrease in proliferation of liver hepatocytes with exposure to both Mjosa mixtures. In addition, immunopositivity for vitellogenin in the liver was significantly lower in the Mjosa high group than in the control group. When analysing effects of parental exposure, fish with parents exposed to Mjosa high mixture had significantly higher numbers of perinucleolar follicles than fish with control parents. We conclude that long-term exposure of a real-life mixture of pollutants containing high- and background levels of chemicals supress ovarian follicle development, liver vitellogenin immunostaining intensity and hepatocyte proliferation in the zebrafish model.

  19. Biphenyl 4-Hydroxylases Involved in Aucuparin Biosynthesis in Rowan and Apple Are Cytochrome P450 736A Proteins.

    Science.gov (United States)

    Sircar, Debabrata; Gaid, Mariam M; Chizzali, Cornelia; Reckwell, Dennis; Kaufholdt, David; Beuerle, Till; Broggini, Giovanni A L; Flachowsky, Henryk; Liu, Benye; Hänsch, Robert; Beerhues, Ludger

    2015-06-01

    Upon pathogen attack, fruit trees such as apple (Malus spp.) and pear (Pyrus spp.) accumulate biphenyl and dibenzofuran phytoalexins, with aucuparin as a major biphenyl compound. 4-Hydroxylation of the biphenyl scaffold, formed by biphenyl synthase (BIS), is catalyzed by a cytochrome P450 (CYP). The biphenyl 4-hydroxylase (B4H) coding sequence of rowan (Sorbus aucuparia) was isolated and functionally expressed in yeast (Saccharomyces cerevisiae). SaB4H was named CYP736A107. No catalytic function of CYP736 was known previously. SaB4H exhibited absolute specificity for 3-hydroxy-5-methoxybiphenyl. In rowan cell cultures treated with elicitor from the scab fungus, transient increases in the SaB4H, SaBIS, and phenylalanine ammonia lyase transcript levels preceded phytoalexin accumulation. Transient expression of a carboxyl-terminal reporter gene construct directed SaB4H to the endoplasmic reticulum. A construct lacking the amino-terminal leader and transmembrane domain caused cytoplasmic localization. Functional B4H coding sequences were also isolated from two apple (Malus × domestica) cultivars. The MdB4Hs were named CYP736A163. When stems of cv Golden Delicious were infected with the fire blight bacterium, highest MdB4H transcript levels were observed in the transition zone. In a phylogenetic tree, the three B4Hs were closest to coniferaldehyde 5-hydroxylases involved in lignin biosynthesis, suggesting a common ancestor. Coniferaldehyde and related compounds were not converted by SaB4H.

  20. Electro-optic and dynamic studies of biphenyl benzoate ferroelectric liquid crystals

    Energy Technology Data Exchange (ETDEWEB)

    Hemine, J., E-mail: hemine1@yahoo.f [Laboratoire de Physique de la Matiere Condensee, Universite Hassan II, Mohammedia-Casablanca, BP 146, F.S.T. Mohammedia (Morocco); Daoudi, A. [Universite Lille Nord de France, F-59000 Lille (France); ULCO, LDSMM, F-59140 Dunkerque (France); CNRS UMR8024, F-59140 Dunkerque (France); Legrand, C. [Universite Lille Nord de France, F-59000 Lille (France); ULCO, LEMCEL, F-62228 Calais (France); El kaaouachi, A.; Nafidi, A. [Laboratoire de Physique de la Matiere Condensee, Faculte des Sciences Ibnou Zohr, BP 28/S 80000 Agadir (Morocco); Ismaili, M.; Isaert, N. [Universite Lille Nord de France, F-59000 Lille (France); USTL, LDSMM, F-59655 Villeneuve d' Ascq (France); CNRS UMR8024, F-59655 Villeneuve d' Ascq (France); Nguyen, H.T. [Centre de Recherche Paul Pascal, Universite de Bordeaux 1, 33600 Pessac (France)

    2010-05-01

    We present electro-optic and dynamic properties on three homologous of biphenyl benzoate series of ferroelectric liquid crystals (FLCs) exhibiting the chiral smectic C phase (SmC*). The three compounds present high spontaneous polarization and show the SmC*-SmA*-N* phase sequence. Dielectric spectroscopy was used to provide the dynamics and dipolar ordering of the ferroelectric phase. The Goldstone relaxation mode was studied for sample cells on planar geometry without a DC bias voltage. The rotational viscosity corresponding to molecular motions in the SmC* phase was determined from dielectric measurements. The Arrhenius-type behavior of the rotational viscosity was found and the corresponding activation energies were evaluated.

  1. Biodegradation Of Persistent Organic Pollutants (POPs):I The Case Of Polychlorinated Biphenyls (PCB)

    International Nuclear Information System (INIS)

    Persistent organic pollutants are chemicals that are toxic to humans and wildlife, remain intact in the environment for long periods, accumulate in living organisms and can become widely distributed geographically by air, water or migrating species. As a result, these contaminants have been found all over the world including in places,such as the Polar Regions, which are very far from their application site. The Stockholm Convention was signed in 23/5/01 in order to cope with this international environmental problem. Although POPs were banned by most countries, there are still a lot of sites contaminated with these substances. The remediation of these sites is problematic and requires distinct considerations from those which are established for hydrocarbon remediation. This manuscript reviews the literature about anaerobic and aerobic biodegradation of polychlorinated biphenyls (PCB) and possible strategies to stimulate these processes. The degradation of the other POPs would be reviewed in additional texts.

  2. Spermatogenic capacity in fertile men with elevated exposure to polychlorinated biphenyls

    DEFF Research Database (Denmark)

    Petersen, Maria Skaalum; Halling, Jónrit; Weihe, Pál;

    2015-01-01

    BACKGROUND: Endocrine disrupting industrial chemicals, such as polychlorinated biphenyls (PCBs), are suspected to adversely affect male reproductive functions. OBJECTIVES: The Faroe Islands community exhibits an unusually wide range of exposures to dietary contaminants, and in this setting we...... examined the possible association between PCB exposure and semen quality and reproductive hormones in fertile Faroese men. METHODS: Participants in this cross-sectional study include 266 proven fertile men residing in the Faroe Islands. PCB levels and hormone profiles were measured in serum samples taken...... at the clinical examination that included semen quality parameters. RESULTS: A significant positive association was seen between serum-PCB and the testosterone/estradiol ratio (p=0.04). In the unadjusted analyses, elevated PCB exposure was associated with increased serum concentrations of SHBG (p=0...

  3. Organochlorine Pesticides (OCs) and Polychlorinated Biphenyls (PCBs) in Tilapia zillii from Lake El-Manzala, Egypt

    International Nuclear Information System (INIS)

    A fresh water fish species, (Tilapia zillii) from Lake El-Manzala was analyzed for concentrations of several Organochlorine pesticides (OCs) and Polychlorine piphenyl's (PCBs) in liver, gonads, mesenteric fat, flesh and the digestive tract in mature fish during the breeding season. Polychlorinated piphenyls (PCBs) and Organochloripe pesticides (OCs) were calculated in (ng/g) dry weight (dw) in homogenized samples. The obtained results revealed differences in lipid content between these different organs. The females showed higher lipid content than males. There was significant positive correlation the lipid content and organochlorines and polychlorinated biphenyls (PCBs). The results come concomitant with the lipophilicity of studied compounds. However, the recoded concentration of these studied pollutants still does not exceed international hazardous levels. (author)

  4. Temperature of hydrogen radio frequency plasma under dechlorination process of polychlorinated biphenyls

    Energy Technology Data Exchange (ETDEWEB)

    Inada, Y., E-mail: inada@hvg.t.u-tokyo.ac.jp; Abe, K.; Kumada, A.; Hidaka, K. [Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Amano, K.; Itoh, K.; Oono, T. [R and D Center, Tokyo Electric Power Company, 4-1 Egasaki-cho, Tsurumi-ku, Yokohama 230-8510 (Japan)

    2014-10-27

    It has been reported that RF (radio frequency) hydrogen plasmas promote the dechlorination process of PCBs (polychlorinated biphenyls) under irradiation of MW (microwave). A relative emission intensity spectroscope system was used for single-shot imaging of two-dimensional temperature distributions of RF hydrogen plasmas generated in chemical solutions with several mixing ratios of isopropyl alcohol (IPA) and insulation oil under MW irradiation. Our experimental results showed that the plasma generation frequencies for the oil-contaminating solutions were higher than that for the pure IPA solution. In addition, the plasma temperature in the compound liquids including both oil and IPA was higher than that in the pure IPA and oil solutions. A combination of the plasma temperature measurements and plasma composition analysis indicated that the hydrogen radicals generated in a chemical solution containing the equal volumes of IPA and oil were almost the same amounts of H and H{sup +}, while those produced in the other solutions were mainly H.

  5. Problems with the polychlorinated biphenyls (PCB) in Mexico; Problematica de los bifenilos policlorados (BPC) en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Valle, Esteban; Cruz, Maria Guadalupe [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    A general overview is presented of the problems with the polychlorinated biphenyls (PCB) (askarels) in Mexico, which are mainly associated with the use of these substances in electric equipment; also, a profile of the causes why the PCBs have been classified as environmental toxic substances and a potential hazard for the health of human beings. [Espanol] Se presenta un panorama general de la problematica de bifenilos policlorados (BPC) (askareles) en Mexico, la cual esta asociada principalmente con el uso de estos compuestos en equipos electricos; asimismo, se describe una semblanza de las causas por las cuales se han catalogado a los BPC como sustancias toxicas ambientales y un peligro potencial para la salud de los seres humanos.

  6. Studies on biphenyl disulphonic acid doped polyanilines: Synthesis, characterization and electrochemistry

    Indian Academy of Sciences (India)

    Chepuri R K Rao; R Muthukannan; M Vijayan

    2012-06-01

    In this article, we report on the results obtained for the efforts we made to bring processability to the conducting polyaniline and substituted polyanilines by designing and synthesizing a new disulphonic acid with a biphenyl moiety as spacer group, viz. 4,4'-biphenyldisulphonic acid (BPSA). When doped, the disulphonic acid acts as a spacer group between the polyaniline chains and facilitates increase in solubility and conductivity. The spacing effect is maximized when BPSA is used as doping agent in in situ polymerization reactions. The conductivity of polyaniline doped by BPSA is 4 S/cm and for the substituted polyanilines it ranged from 2 × 10-5 to 8 × 10-4 S/cm.

  7. Studies on the Quantitative Structure-activity Relationship of Substituted Biphenyls by Density Function Theory (DFT)

    Institute of Scientific and Technical Information of China (English)

    HAN Xiang-Yun; ZHENG Qing

    2007-01-01

    Geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311G** level with Gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna (-lgEC50)was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients (lgKow), dipole moment of the molecules (μ) and entropy (S°). For this equation, R2 =0.9582, q2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

  8. Relationships between polychlorinated biphenyls in molluscs, hydrological characteristics and human pressures, within Basque estuaries (northern Spain).

    Science.gov (United States)

    Solaun, O; Rodríguez, J G; Borja, A; Larreta, J; Valencia, V

    2015-01-01

    Interannual variability of polychlorinated biphenyls (PCBs), measured in the soft tissues of Mytilus galloprovincialis mussels and Crassostrea gigas oysters, collected from estuarine waters within the Basque Country (Bay of Biscay), are investigated. Samples were collected in the autumn, between 2002 and 2011. Sites located within the ports of Bilbao and Pasaia showed the highest PCBs concentrations in molluscs; the lowest were observed in the mouth of the Oka estuary, an area of low population and industrial activity. Congener profiles of PCBs in the tissues of molluscs reveal the predominance of hexachlorobiphenyls (CB153 and CB138). In addition, redundancy analysis has shown that residence time, river flow and a 'pressure index' explain 57% of the variability in the PCB congener concentrations (the higher the values of these variables, the higher the concentration). Finally, Σ7PCB median concentrations in molluscs and sediments, collected from nearby sampling sites, were found to be moderately correlated (r(2)=0.513, p<0.01).

  9. Digestive tract absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant

    Energy Technology Data Exchange (ETDEWEB)

    McLachlan, M.S. (Univ. of Bayreuth (Germany))

    1993-11-01

    The digestive tract absorption of environmental contaminants is an important but poorly understood parameter in contaminant is an important but poorly understood parameter in contaminant risk assessments. The net absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant was measured under natural conditions over 12 days. The levels of the substances in the mother's milk were typical for Germany. It was found that for almost all congeners over 90% of the ingested compound was absorbed. This indicates that the common assumption of 100% absorption in nursing infants is reasonable. No firm conclusions could be drawn regarding the absorption of Cl7- and Cl8DD/F due to high blank levels in the cotton diapers used.

  10. [EVALUATION OF MIGRATION ABILITY OF POLYCHLORINATED BIPHENYLS IN THE "SOIL-PLANT" AND "SOIL-EARTHWORMS"].

    Science.gov (United States)

    Baeva, Yu I; Chernykh, N A

    2016-01-01

    In the article there is given a hygienic assessment ofpolychlorinated biphenyls (PCBs) contamination of soils of the city of Serpukhov of the Moscow region. For the first time there was investigated the PCB's ability to migrate in the system "soil-earthworms", and were calculated bioaccumulation factors at the different level of soil contamination. There was performed a comparative evaluation of the accumulation of given contaminants by higher terrestrial plants and representatives of soil paedobionts (Lumbricidae worms), and revealed clear differences in these processes. There was shown the possibility of the use of earthworms as a highly sensitive bio-indicators in monitoring for soil contamination by persistent organic pollutants, even at low concentrations. PMID:27430062

  11. [Application prospect about bioremediation of polychlorinated biphenyls-contaminated soil with immobilized microorganism technique: a review].

    Science.gov (United States)

    Hu, Jin-Xing; Su, Xiao-Mei; Han, Hui-Bo; Shen, Chao-Feng; Shi, Ji-Yan

    2014-06-01

    As one type of the persistent organic pollutants, polychlorinated biphenyls (PCBs) are tremendously harmful to organisms. These compounds are easily absorbed onto soil particles and able to accumulate in soil after they are released into the environment. Bioremediation technology of PCBs-contaminated soils has become a research hotspot in recent years, and immobilized microorganism technique has high developing and applying value because of its unique advantages in environmental remediation. This paper reviewed the chief remediation technology of PCBs-contaminated soils and then analyzed the characteristics of immobilized microorganism technique and its research progress in remediation of organic polluted soil. Finally, the feasibility and problems of this technique in remediation of PCBs-contaminated soil were also discussed.

  12. Persistent organochlorine residues and toxic evaluation of polychlorinated biphenyls in sharks from the Mediterranean Sea (Italy)

    Energy Technology Data Exchange (ETDEWEB)

    Storelli, M.M.; Marcotrigiano, G.O. [Bari Univ., Dip. Farmaco-Biologico, Bari (Italy)

    2001-07-01

    Persistent organochlorines such as polychlorinated biphenyls including coplanar congeners, DDT compounds and HCB were measured in different tissues (muscle, liver and eggs) of two Mediterranean shark species: namely Centrophorus granulosus and Squalus blainvillei. The concentrations of organochlorines in the tissues and organs of both species were in the order DDTs>PCBs>HCB. The highest values of DDTs, PCBs and HCB were found in liver followed by eggs and muscle. Among DDTs the compound found in greatest concentration was p,p -DDE. The PCB profiles were dominated by congeners 138, 153, and 180. The isomers with higher TEQs values were non- and mono-ortho congeners than di-ortho ones in muscle, liver and eggs of both species. Among the non-ortho, PCB 126 was the major contributing individual to the total TEQs in both species. (Author)

  13. Contamination of soil, leaves and vegetables by polychlorinated biphenyls in Xiamen region, China

    Institute of Scientific and Technical Information of China (English)

    MASKAOUI Khalid; ZHOU Jun-liang; HAN Ya-li; HU Zhong; ZHENG Tian-ling; HONG Hua-sheng

    2005-01-01

    The paper aimed to identify the primary of polychlorinated biphenyls(PCBs) in the diulong River Estuary, investigate the spatial distribution of PCBs contamination in the environment, localize the atmospheric source and evaluate ongoing PCBs emissions by analyzing soil samples collected along the Jiulong River region. In addition, the accumulation of PCBs in the human food chain was quantified by analyzing leaf of orange trees and vegetable samples collected along a gradient of soil/atmospheric contamination moving away from the source. Consequently, the impact on the human health and the ecosystem was quantified, different management options were proposedto reduce this impact and to carry out research on organic contaminants along the Jiulong River and Xiamen region.

  14. Effect of highly bioaccumulated polychlorinated biphenyl congeners on estrogen and androgen receptor activity

    DEFF Research Database (Denmark)

    Bonefeld-Jørgensen, E.C.; Andersen, H. R.; Rasmussen, T.H.;

    2001-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitous environmental persistent contaminants giving rise to potential health hazard. Some PCBs exert dioxin-like activities mediated through the aryl hydrocarbon receptor. Although reports on interaction with other nuclear receptors are sparce, some...... pleiotropic effects on the estrogen- and androgen-receptor. In MCF-7 cells a slightly increased cell proliferation was observed at low concentrations (1-10 nM) in cells co-treated with 0.01 nM 17 beta -Estradiol. whereas the compounds inhibited cell growth significantly at 1 and 10 muM. In reporter gene (ERE......-tk-CAT) analysis the three congeners exhibited a significantly estrogen receptor-ligand mediated decrease of the chloramphenicol transferase activity in both control and 10 nM 17 beta -estradiol induced MCF-7 cells. In addition, PCB # 138 elicited a dose-dependent antagonistic effect on androgen receptor activity...

  15. Distribution characteristics of polychlorinated biphenyls (PCBs) in coastal areas of Okinawa Island, Japan

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Surface sediment and seawater samples were collected from coastal areas around Okinawa Island from September 2001 to May 2002. The samples were analyzed for total polychlorinated biphenyl (PCB) levels and homolog composition. The results show that total PCB levels ranged from 0.32 to 128.7 ng/g (dry wt.) in sediment and 1.59 to 2.48 ng/L in seawater. The levels exceed the Environmental Quality Standard (EQS) for water pollution of Japan. The distribution of PCB homolog showed different patterns in the sediments and seawaters. Penta-chlorobiphenyls (CBs) comprised the main congener group in seawater, while hexa-CBs were more abundant homologs in the sediments. The heavily contaminated sites featured higher CBs, including penta-CBs, hexa-CBs, and hepta-CBs, than those in less contaminated sites where tri-CBs dominated. This study provides current distribution and geochemical behavior of PCBs in the coastal areas around Okinawa Island.

  16. Effects of pesticides, polychlorinated biphenyls and metals on the growth and reproduction of Acanthamoeba castellanii

    Energy Technology Data Exchange (ETDEWEB)

    Prescott, L.M.; Kubovec, M.K.; Tryggestad, D.

    1977-07-01

    The effects of pollutants (pesticides, PCB and metals) were studied in the free-living amoeba, Acanthamoeba castellanii. Eight pesticides were used--the insecticides dieldrin, aldrin and sevin, and the herbicides linuron, stam F-34, IPC, atrazine and simazine. It was shown that the sensitivity of A. castellanii to pesticides varied greatly. The population growth was inhibited by linuron, stam F-34, IPC, sevin and atrazine at a level of 10 mg/l. The polychlorinated biphenyl, Arochor 1254, had no significant effect at a concentration of 0.01 mg/l (10 ppb). The studies with metal ions showed that A. castellanii was unaffected by moderately high levels of Cu and Zn, but was sensitive to the presence of Pb and mercuric ions.

  17. Biphenyls from the Twigs of Garcinia multiflora and their AntiTobacco Mosaic Virus Activities

    Directory of Open Access Journals (Sweden)

    Xingmeng Xu

    2016-03-01

    Full Text Available For more bioactive compounds, p hytochemical investigations of the acetone extract of the twigs G arcinia multiflora resulted in the isolation of two new bipheny ls, multiflorabiphenyls A and B (1 and 2 , along with four known biphenyl derivatives (3-6 . Structural elucidations of 1 and 2 were performed by spectral methods such as 1D and 2D NMR spectroscopy, in addition to high resolution mass spectrometry. Compounds 1 and 2 were also evaluated for their anti-tobacco mosaic virus (Anti-TMV activity. The results showed that compound s 1 and 2 showed high anti-TMV activit ies with inhibition rate s of 25.4 % and 28.3%, respectively, which is close d to that of Ningnanmycin ( 3 3.5 %.

  18. Dioxins, furans, and polychlorinated biphenyls in hen eggs – a new source of hazard for consumers?

    Directory of Open Access Journals (Sweden)

    Piskorska-Pliszczyńska Jadwiga

    2015-12-01

    Full Text Available The paper presents the results of testing eggs for the content of dioxins and polychlorinated biphenyls (PCBs, determination of the sources that caused the presence of high concentrations of these compounds which exceeded the acceptable contamination levels, and assessment of consumer health risk caused by the consumption of eggs with excessive contents of investigated compounds. In about 9% of free range eggs and 17% of organic eggs, the content of PCDD/Fs was two- or threefold higher than the acceptable limits, and in some samples the concentration of investigated compounds exceeded the maximum concentration levels. Based on the profile of the compounds, it was confirmed in several cases that their main source was the soil or unsecured refuse. The consumers of eggs and meat produced under these conditions constitute the risk groups, and their dioxin and PCB intake may exceed toxicological reference values.

  19. Assessment of polychlorinated biphenyls and organochlorine pesticides in water samples from the Yamuna River

    Directory of Open Access Journals (Sweden)

    Bhupander Kumar

    2012-07-01

    Full Text Available Polychlorinated biphenyls (PCBs, hexachlorocyclohexane (HCH and dichlorodiphenyltrichloroethane (DDT are toxic, persistent and bioaccumulative long-range atmospheric transport pollutants. These are transported worldwide affecting remote regions far from their original sources, and can transfer into food webs with a wide range of acute and chronic health effects. India ratified the Stockholm Convention with the intention of reducing and eliminating persistent organic pollutants (POPs, and encouraged the support of research on POPs. Despite the ban and restriction on the use of these chemicals in India, their contamination of air, water, sediment, biota and humans has been reported. In this study, surface water samples were collected during January 2012 from the Yamuna River in Delhi, India, and analyzed for PCBs and organochlorine pesticides (OCPs. The concentrations of ΣPCBs and ΣOCPs ranged between 2-779 ng L–1 and from less than 0.1 to 618 ng L–1 (mean 99±38 ng L–1 and 221±50 ng L–1, respectively. The PCB homolog was dominated by 3-4 chlorinated biphenyls. In calculating the toxicity equivalent of dioxin-like PCBs (dl-PCBsusing World Health Organization toxic equivalency factors, dl-PCBs accounted for 10% of a total of 27 PCBs. The concentration of ΣHCH ranged between less than 0.1 and 285 ng L–1 (mean 151±32 ng L–1. However, ΣDDTs concentrations varied between less than 0.1 and 354 ng L–1 (mean 83±26 ng L–1. The concentrations were lower than the US guideline values; however, levels of lindane exceeded those recommended in guidelines. Further in-depth study is proposed to determine the bioaccumulation of these pollutants through aquatic biota to assess the risk of contaminants to human health.

  20. Synthesis and Properties of a Novel Polyimide with Side Chain Containing Biphenyl Unit

    Institute of Scientific and Technical Information of China (English)

    WANG Xu; CHANG Tong-xin; ZHANG Peng; CHEN Yi; LIU Xiang-yang

    2012-01-01

    A novel biphenyl side-chained diamine with alkyloxy spacer and alkyloxy tail,4'-butoxy-4-(3,5-diami-nobenzoyloxy)hexyloxybiphenyl(C6BBC4),was synthesized and characterized by FTIR and 1H NMR.A series of polyimide(PI)films with different side chain contents was synthesized from biphenyltetracarboxylicdianhydride (BPDA),4,4'-oxydianiline(ODA)and C6BBC4,and their thermal properties,optical transparency and liquid crystal alignment property,and so on,were investigated by thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),crystal rotation method,polarizing microscopy and UV-Vis spectra.With the content of side chained diamine increasing from 0 to 100%,the ηinh of poly(amide acid)(PAA)decreased rapidly from 3.0 to 0.51,the glass transition temperature(Tg)of polyimides(PIs)decreased from 274 ℃ to 203 ℃ and the Vis-light transmittance of alignment films substantially increased.As for the alignment properties,the pretilt angle of PI alignment films without rubbing could reach 90° when the content of C6BBC4 was 60% or more.At the same time,the alignment stability could meet the industrial requirements.It was considered that the alkoxy spacer,the biphenyl unit and the alkoxy tail may all play important roles in achieving a large pretilt angle even up to 90°,and the introduction of only the alkoxy spacer or alkoxy tail can also improve the pretilt angle,but not by much.

  1. Chlorinated hydrocarbon pesticides and polychlorinated biphenyls in sediment cores from San Francisco Bay

    Science.gov (United States)

    Venkatesan, M.I.; De Leon, R. P.; VanGeen, A.; Luoma, S.N.

    1999-01-01

    Sediment cores of known chronology from Richardson and San Pablo Bays in San Francisco Bay, CA, were analyzed for a suite of chlorinated hydrocarbon pesticides and polychlorinated biphenyls to reconstruct a historic record of inputs. Total DDTs (DDT = 2,4'- and 4,4'-dichlorodiphenyltrichloroethane and the metabolites, 2,4'- and 4,4'-DDE, -DDD) range in concentration from 4-21 ng/g and constitute a major fraction (> 84%) of the total pesticides in the top 70 cm of Richardson Bay sediment. A subsurface maximum corresponds to a peak deposition date of 1969-1974. The first measurable DDT levels are found in sediment deposited in the late 1930's. The higher DDT inventory in the San Pablo relative to the Richardson Bay core probably reflects the greater proximity of San Pablo Bay to agricultural activities in the watershed of the Sacramento and San Joaquin rivers. Total polychlorinated biphenyls (PCBs) occur at comparable levels in the two Bays (inventories in San Pablo Bay are about a factor of four higher in the last four decades than in Richardson Bay, suggesting a distribution of inputs not as strongly weighed towards the upper reaches of the estuary as DDTs. The shallower subsurface maximum in PCBs compared to DDT in the San Pablo Bay core is consistent with the imposition of drastic source control measures four these constituents in 1970 and 1977 respectively. The observed decline in DDT and PCB levels towards the surface of both cores is consistent with a dramatic drop in the input of these pollutants once the effect of sediment resuspension and mixing is taken into account.

  2. Evaluating permanent deformation in asphalt rubber mixtures

    OpenAIRE

    Fontes, Liseane P. T. L.; Trichês, Glicério; Pais, Jorge C.; Pereira, Paulo A. A.

    2009-01-01

    Permanent deformation or rutting, one of the most important distresses inflexible pavements, has long been a problem in asphalt mixtures. Throughout the years, researchers have used different test methods lo estimate the performance of asphalt mixtures in relation to rutting. One of the alternatives to reduce permanent deformation in asphalt pavement layers is through the use of mixtures produced with asphalt rubber This work aims at comparing the performance of a conventional dense graded mi...

  3. Microstructural characterisation of rubber modified asphalt mixtures

    OpenAIRE

    Abdul Hassan, Norhidayah

    2013-01-01

    Research to improve the performance of asphalt mixtures through the addition of crumb rubber using the dry process has continued worldwide because of its potential as a recycling option for used tires. For decades, dry mixed rubberised asphalt mixtures have performed inconsistently in field trials and laboratory evaluations. However, current research has revealed that the performance of asphalt mixtures is highly dependent on the characteristics of its internal structure or phase constituents...

  4. Performance-based asphalt mixture design methodology

    Science.gov (United States)

    Ali, Al-Hosain Mansour

    Today, several State D.O.T.s are being investigating the use of tire rubber with local conventional materials. Several of the ongoing investigations identified potential benefits from the use of these materials, including improvements in material properties and performance. One of the major problems is being associated with the transferability of asphalt rubber technology without appropriately considering the effects of the variety of conventional materials on mixture behavior and performance. Typically, the design of these mixtures is being adapted to the physical properties of the conventional materials by using the empirical Marshall mixture design and without considering fundamental mixture behavior and performance. Use of design criteria related to the most common modes of failure for asphalt mixtures, such as rutting, fatigue cracking, and low temperature thermal cracking have to be developed and used for identifying the "best mixture," in term of performance, for the specific local materials and loading conditions. The main objective of this study was the development of a mixture design methodology that considers mixture behavior and performance. In order to achieve this objective a laboratory investigation able to evaluate mixture properties that can be related to mixture performance, (in terms of rutting, low temperature cracking, moisture damage and fatigue), and simulating the actual field loading conditions that the material is being exposed to, was conducted. The results proved that the inclusion of rubber into asphalt mixtures improved physical characteristics such as elasticity, flexibility, rebound, aging properties, increased fatigue resistance, and reduced rutting potential. The possibility of coupling the traditional Marshall mix design method with parameters related to mixture behavior and performance was investigated. Also, the SHRP SUPERPAVE mix design methodology was reviewed and considered in this study for the development of an integrated

  5. Compositional Adjustment of Dirichlet Mixture Priors

    OpenAIRE

    Ye, Xugang; Yu, Yi-Kuo; Altschul, Stephen F.

    2010-01-01

    Dirichlet mixture priors provide a Bayesian formalism for scoring alignments of protein profiles to individual sequences, which can be generalized to constructing scores for multiple-alignment columns. A Dirichlet mixture is a probability distribution over multinomial space, each of whose components can be thought of as modeling a type of protein position. Applied to the simplest case of pairwise sequence alignment, a Dirichlet mixture is equivalent to an implied symmetric substitution matrix...

  6. Contamination of indoor dust and air by polychlorinated biphenyls and brominated flame retardants and relevance of non-dietary exposure in Vietnamese informal e-waste recycling sites.

    Science.gov (United States)

    Tue, Nguyen Minh; Takahashi, Shin; Suzuki, Go; Isobe, Tomohiko; Viet, Pham Hung; Kobara, Yuso; Seike, Nobuyasu; Zhang, Gan; Sudaryanto, Agus; Tanabe, Shinsuke

    2013-01-01

    This study investigated the occurrence of polychlorinated biphenyls (PCBs), and several additive brominated flame retardants (BFRs) in indoor dust and air from two Vietnamese informal e-waste recycling sites (EWRSs) and an urban site in order to assess the relevance of these media for human exposure. The levels of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), 1,2-bis-(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenyl ethane (DBDPE) in settled house dust from the EWRSs (130-12,000, 5.4-400, 5.2-620 and 31-1400 ng g(-1), respectively) were significantly higher than in urban house dust but the levels of PCBs (4.8-320 ng g(-1)) were not higher. The levels of PCBs and PBDEs in air at e-waste recycling houses (1000-1800 and 620-720 pg m(-3), respectively), determined using passive sampling, were also higher compared with non-e-waste houses. The composition of BFRs in EWRS samples suggests the influence from high-temperature processes and occurrence of waste materials containing older BFR formulations. Results of daily intake estimation for e-waste recycling workers are in good agreement with the accumulation patterns previously observed in human milk and indicate that dust ingestion contributes a large portion of the PBDE intake (60%-88%), and air inhalation to the low-chlorinated PCB intake (>80% for triCBs) due to their high levels in dust and air, respectively. Further investigation of both indoor dust and air as the exposure media for other e-waste recycling-related contaminants and assessment of health risk associated with exposure to these contaminant mixtures is necessary.

  7. Cluster kinetics model for mixtures of glassformers.

    Science.gov (United States)

    Brenskelle, Lisa A; McCoy, Benjamin J

    2007-10-14

    For glassformers we propose a binary mixture relation for parameters in a cluster kinetics model previously shown to represent pure compound data for viscosity and dielectric relaxation as functions of either temperature or pressure. The model parameters are based on activation energies and activation volumes for cluster association-dissociation processes. With the mixture parameters, we calculated dielectric relaxation times and compared the results to experimental values for binary mixtures. Mixtures of sorbitol and glycerol (seven compositions), sorbitol and xylitol (three compositions), and polychloroepihydrin and polyvinylmethylether (three compositions) were studied. PMID:17935407

  8. Shear viscosity of liquid mixtures: Mass dependence

    International Nuclear Information System (INIS)

    Expressions for zeroth, second, and fourth sum rules of transverse stress autocorrelation function of two component fluid have been derived. These sum rules and Mori's memory function formalism have been used to study shear viscosity of Ar-Kr and isotopic mixtures. It has been found that theoretical result is in good agreement with the computer simulation result for the Ar-Kr mixture. The mass dependence of shear viscosity for different mole fraction shows that deviation from ideal linear model comes even from mass difference in two species of fluid mixture. At higher mass ratio shear viscosity of mixture is not explained by any of the emperical model. (author)

  9. Critical evaluation of polychlorinated biphenyl toxicity in terrestrial and marine mammals: increasing impact of non-ortho and mono-ortho coplanar polychlorinated biphenyls from land to ocean.

    Science.gov (United States)

    Kannan, N; Tanabe, S; Ono, M; Tatsukawa, R

    1989-11-01

    Residues of potentially toxic non-ortho chlorine substituted coplanar 3,3',4,4'-tetra-,3,3',4,4',5-penta-, 3,3',4,4',5,5'-hexachlorobiphenyl and their mono- and di-ortho analogs 2,3',4,4',5-penta, 2,3,3',4,4'-penta-, 2,3,3',4,4',5-hexa- and 2,2',3,3',4,4'-hexa-, 2,2',3,4,4',5-hexachlorobiphenyl) were determined in humans, dogs, cats (terrestrial), a finless porpoise (Neophocoena phocoenoides--coastal), Dall's porpoises (Phocoenoides dalli, dalli), Baird's beaked whales (Berardius bairdii) and killer whales (Orcinus orca--open ocean). Among the coplanar polychlorinated biphenyl (PCB) congeners, the concentration of the di-ortho congeners was the highest and the non-ortho congeners was the lowest. However, all three coplanar PCBs occurred at significantly higher levels than toxic polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The relative bioconcentration and metabolic capacity of terrestrial and marine mammals to these chemicals, suggest that the toxic threat of coplanar PCBs increases from land to ocean, but the reverse is true for PCDDs and PCDFs. The toxic threat of coplanar PCBs to higher aquatic predators such as cetaceans was principally assessed by 2,3,7,8-T4CDD Toxic Equivalent Analysis which is based on the induction of arylhydrocarbon hydroxylase (AHH) and ethoxyresorufin O-deethylase (EROD). Analysis indicates, in particular, that the bioaccumulation of toxic 3,3',4,4',5-penta- and 2,3,3',4,4'-pentachlorobiphenyls in carnivorous marine mammals is a cause for considerable concern. PMID:2515809

  10. A cohort study of the association between secondary sex ratio and parental exposure to polybrominated biphenyl (PBB and polychlorinated biphenyl (PCB

    Directory of Open Access Journals (Sweden)

    Terrell Metrecia L

    2009-08-01

    Full Text Available Abstract Background Polybrominated biphenyl (PBB, a brominated flame retardant, was accidently mixed into animal feed in Michigan (1973–1974 resulting in human exposure through consumption of contaminated meat, milk and eggs. Beginning in 1976 individuals who consumed contaminated products were enrolled in the Michigan Long-Term PBB Study. This cohort presents a unique opportunity to study the association between parental exposures to PBB and offspring sex ratio. Methods We identified offspring of female PBB cohort participants (born 1975–1988 and obtained electronic birth records for those born in the state of Michigan. We linked this information to parental serum PBB and PCB concentrations collected at enrollment into the cohort. We modeled the odds of a male birth with generalized estimating equations accounting for the non-independence of siblings born to the same parents. We explored potential confounders: parental age and education at offspring's birth, parental body mass index at cohort enrollment, birth order, gestational age and year of offspring's birth. Results The overall proportion of male offspring among 865 live births to cohort mothers was 0.542. This was higher than the national male proportion of 0.514 (binomial test: p = 0.10. When both parents were in the cohort (n = 300, we found increased odds of a male birth with combined parents' enrollment PBB exposure ≥ the median concentrations (3 μg/L for mothers; 6 μg/L for fathers compared to combined parents' PBB exposure Conclusion This study adds to the body of literature on secondary sex ratio and exposure to environmental contaminants. In this population, combined parental exposure to PBBs or PCBs increased the odds of a male birth. Further research is needed to corroborate these findings and shed light on the biological mechanisms by which these types of chemicals may influence the secondary sex ratio.

  11. Thermodynamics of mixtures containing amines

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Juan Antonio [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain)], E-mail: jagl@termo.uva.es; Mozo, Ismael; Garcia de la Fuente, Isaias; Cobos, Jose Carlos [G.E.T.E.F. Dpto Termodinamica y Fisica Aplicada, Facultad de Ciencias, Universidad de Valladolid, Valladolid 47071 (Spain); Riesco, Nicolas [Department of Chemical Engineering, Loughborough University, Loughborough, LE113TU Leicestershire (United Kingdom)

    2008-01-30

    Mixtures with dimethyl or trimethylpyridines and alkane, aromatic compound or 1-alkanol have been examined using different theories: DISQUAC, Flory, the concentration-concentration structure factor, S{sub CC}(0), or the Kirkwood-Buff formalism. DISQUAC represents fairly well the available experimental data, and improves theoretical calculations from Dortmund UNIFAC. Two important effects have been investigated: (i) the effect of increasing the number of methyl groups attached to the aromatic ring of the amine; (ii) the effect of modifying the position of the methyl groups in this ring. The molar excess enthalpy, H{sup E}, and the molar excess volume, V{sup E}, decrease in systems with alkane or methanol as follows: pyridine > 3-methylpyridine > 3,5-dimethylpyridine and pyridine > 2-methylpyridine > 2,4-dimethylpyridine > 2,4,6-trimethylpyridine, which has been attributed to a weakening of the amine-amine interactions in the same sequences. This is in agreement with the relative variation of the effective dipole moment, {mu}-bar, and of the differences between the boiling temperature of a pyridine base and that of the homomorphic alkane. For heptane solutions, the observed H{sup E} variation, H{sup E} (3,5-dimethylpyridine) > H{sup E} (2,4-dimethylpyridine) > H{sup E} (2,6-dimethylpyridine), is explained similarly. Calculations on the basis of the Flory model confirm that orientational effects become weaker in systems with alkane in the order: pyridine > methylpyridine > dimethylpyridine > trimethylpyridine. S{sub CC}(0) calculations show that steric effects increase with the number of CH{sub 3}- groups in the pyridine base, and that the steric effects exerted by methyl groups in positions 2 and 6 are higher than when they are placed in positions 3 and 5. The hydrogen bond energy in methanol mixtures is independent of the pyridine base, and it is estimated to be -35.2 kJ mol{sup -1}. Heterocoordination in these solutions is due in part to size effects. Their

  12. Simulation of mixture microstructures via particle packing models and their direct comparison with real mixtures

    Science.gov (United States)

    Gulliver, Eric A.

    The objective of this thesis to identify and develop techniques providing direct comparison between simulated and real packed particle mixture microstructures containing submicron-sized particles. This entailed devising techniques for simulating powder mixtures, producing real mixtures with known powder characteristics, sectioning real mixtures, interrogating mixture cross-sections, evaluating and quantifying the mixture interrogation process and for comparing interrogation results between mixtures. A drop and roll-type particle-packing model was used to generate simulations of random mixtures. The simulated mixtures were then evaluated to establish that they were not segregated and free from gross defects. A powder processing protocol was established to provide real mixtures for direct comparison and for use in evaluating the simulation. The powder processing protocol was designed to minimize differences between measured particle size distributions and the particle size distributions in the mixture. A sectioning technique was developed that was capable of producing distortion free cross-sections of fine scale particulate mixtures. Tessellation analysis was used to interrogate mixture cross sections and statistical quality control charts were used to evaluate different types of tessellation analysis and to establish the importance of differences between simulated and real mixtures. The particle-packing program generated crescent shaped pores below large particles but realistic looking mixture microstructures otherwise. Focused ion beam milling was the only technique capable of sectioning particle compacts in a manner suitable for stereological analysis. Johnson-Mehl and Voronoi tessellation of the same cross-sections produced tessellation tiles with different the-area populations. Control charts analysis showed Johnson-Mehl tessellation measurements are superior to Voronoi tessellation measurements for detecting variations in mixture microstructure, such as altered

  13. CHARACTERIZATION OF PCB (POLYCHLORINATED BIPHENYL) TRANSFORMER/CAPACITOR FLUIDS AND CORRELATION WITH PCDDS (POLYCHLORINATED DIBENZO-P-DIOXINS) AND PCDFS (POLYCHLORINATED DIBENZOFURANS) IN SOOT

    Science.gov (United States)

    Dielectric fluids in transformers and capacitors often contain polychlorinated biphenyls (PCBs) or chlorobenzenes. These substances may generate polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-p-dioxins (PCDDs) under certain conditions of combustion/pyrolysis. W...

  14. STAR-POLYMER -- COLLOID MIXTURES

    Directory of Open Access Journals (Sweden)

    J.Dzubiella

    2002-01-01

    Full Text Available Recent results in theory and simulation of star-polymer--colloid mixtures are reviewed. We present the effective interaction between hard, colloidal particles and star polymers in a good solvent derived by monomer-resolved Molecular Dynamics simulations and theoretical arguments. The relevant parameters are the size ratio q between the stars and the colloids, as well as the number of polymeric arms f (functionality attached to the common center of the star. By covering a wide range of q's ranging from zero (star against a flat wall up to about 0.5, we establish analytical forms for the star-colloid interaction which are in excellent agreement with simulation results. By employing this cross interaction and the effective interactions between stars and colloids themselves, a demixing transition in the fluid phase is observed and systematically investigated for different arm numbers and size ratios. The demixing binodals are compared with experimental observations and found to be consistent. Furthermore, we map the full two-component system on an effective one-component description for the colloids, by inverting the two-component Ornstein-Zernike equations. Some recent results for the depletion interaction and freezing transitions are shown.

  15. The effect of dietary glycine on the hepatic tumor promoting activity of polychlorinated biphenyls (PCBs) in rats

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) are ubiquitious lipophilic environmental pollutants. Some of the PCB congeners and mixtures of congeners have tumor promoting activity in rat liver. The mechanism of their activity is not fully understood and is likely to be multifactorial. The aim of this study was to investigate if the resident liver macrophages, Kupffer cells, are important in the promoting activity of PCBs. The hypothesis of this study was that the inhibition of Kupffer cell activity would inhibit hepatic tumor promotion by PCBs in rats. To test our hypothesis, we studied the effects of Kupffer cell inhibition by dietary glycine (an inhibitor of Kupffer cell secretory activity) in a rat two-stage hepatocarcinogenesis model using 2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153, a non-dioxin-like PCB) or 3,3',4,4'-tetrachlorobiphenyl (PCB-77, a dioxin-like PCB) as promoters. Diethylnitrosamine (DEN, 150 mg/kg) was administered to female Sprague-Dawley rats, which were then placed on an unrefined diet containing 5% glycine (or casein as nitrogen control) starting two weeks after DEN administration. On the third day after starting the diets, rats received PCB-77 (300 μmol/kg), PCB-153 (300 μmol/kg), or corn oil by i.p. injection. The rats received a total of 4 PCB injections, administered every 14 days. The rats were euthanized on the 10th day after the last PCB injection, and the formation of altered hepatic foci expressing placental glutathione S-transferase (PGST) and the rate of DNA synthesis in these foci and in the normal liver tissue were determined. Glycine did not significantly affect foci number or volume. PCB-153 did not significantly increase the focal volume, but increased the number of foci per liver, but only in the rats not fed glycine; PCB-77 increased both the foci number and their volume in both glycine-fed and control rats. Glycine did not alter the PCB content of the liver, but did increase the activity of 7-benzyloxyresorufin O-dealkylase (BROD

  16. The Modified Enskog Equation for Mixtures

    NARCIS (Netherlands)

    Beijeren, H. van; Ernst, M.H.

    1973-01-01

    In a previous paper it was shown that a modified form of the Enskog equation, applied to mixtures of hard spheres, should be considered as the correct extension of the usual Enskog equation to the case of mixtures. The main argument was that the modified Enskog equation leads to linear transport coe

  17. Fibril assembly in whey protein mixtures

    NARCIS (Netherlands)

    Bolder, S.G.

    2007-01-01

    The objective of this thesis was to study fibril assembly in mixtures of whey proteins. The effect of the composition of the protein mixture on the structures and the resulting phase behaviour was investigated. The current work has shown that beta-lactoglobulin is responsible for the fibril assembly

  18. A gamma model for {DNA} mixture analyses

    OpenAIRE

    Cowell, R. G.; Lauritzen, S L; Mortera, J.

    2007-01-01

    We present a new methodology for analysing forensic identification problems involving DNA mixture traces where several individuals may have contributed to the trace. The model used for identification and separation of DNA mixtures is based on a gamma distribution for peak area values. In this paper we illustrate the gamma model and apply it on several real examples from forensic casework.

  19. Separation of organic azeotropic mixtures by pervaporation

    Energy Technology Data Exchange (ETDEWEB)

    Baker, R.W.

    1991-12-01

    Distillation is a commonly used separation technique in the petroleum refining and chemical processing industries. However, there are a number of potential separations involving azetropic and close-boiling organic mixtures that cannot be separated efficiently by distillation. Pervaporation is a membrane-based process that uses selective permeation through membranes to separate liquid mixtures. Because the separation process is not affected by the relative volatility of the mixture components being separated, pervaporation can be used to separate azetropes and close-boiling mixtures. Our results showed that pervaporation membranes can be used to separate azeotropic mixtures efficiently, a result that is not achievable with simple distillation. The membranes were 5--10 times more permeable to one of the components of the mixture, concentrating it in the permeate stream. For example, the membrane was 10 times more permeable to ethanol than methyl ethyl ketone, producing 60% ethanol permeate from an azeotropic mixture of ethanol and methyl ethyl ketone containing 18% ethanol. For the ethyl acetate/water mixture, the membranes showed a very high selectivity to water (> 300) and the permeate was 50--100 times enriched in water relative to the feed. The membranes had permeate fluxes on the order of 0.1--1 kg/m{sup 2}{center dot}h in the operating range of 55--70{degrees}C. Higher fluxes were obtained by increasing the operating temperature.

  20. Recursive unsupervised learning of finite mixture models

    NARCIS (Netherlands)

    Zivkovic, Zoran; Heijden, van der Ferdinand

    2004-01-01

    There are two open problems when finite mixture densities are used to model multivariate data: the selection of the number of components and the initialization. In this paper, we propose an online (recursive) algorithm that estimates the parameters of the mixture and that simultaneously selects the

  1. Rheological and commodity properties of petroleum mixtures

    International Nuclear Information System (INIS)

    Results of researches of rheological and commodity characteristics of prognosis petroleum mixtures, pumping on an Western Kazakhstan-Kumkol petroleum pipe-line are presented. It is shown, that petroleum mixtures are low viscous, low solidifying and have not viscosity anomaly at positive temperatures. (author)

  2. Deformation Properties and Fatigue of Bituminous Mixtures

    Directory of Open Access Journals (Sweden)

    Frantisek Schlosser

    2013-01-01

    Full Text Available Deformation properties and fatigue performance are important characteristics of asphalt bound materials which are used for construction of pavement layers. Viscoelastic asphalt mixtures are better characterized via dynamic tests. This type of tests allows us to collate materials with regard to axle vibrations which lie usually in the range of 6 Hz–25 Hz for standard conditions. Asphalt modified for heat sensitivity in the range from −20°C to +60°C has significant impact on the overall characteristics of the mixture. Deformation properties are used as inputs for empirical mixture design, and fatigue performance of asphalt mixtures reflects the parameters of functional tests. Master curves convey properties of asphalt mixtures for various conditions and allow us to evaluate them without the need of time expensive testing.

  3. Mixture toxicity of PBT-like chemicals

    DEFF Research Database (Denmark)

    Syberg, Kristian; Dai, Lina; Ramskov, Tina;

    addition is a suitable model for default estimations of mixture effects. One of the major challenges is therefore how to select specific chemicals for actual mixture toxicity assessments. Persistant chemicals are likely to be present in the environment for an extended period of time, thus increasing......Even though most chemicals regulation is still conducted on a chemical by chemical basis, mixture toxicity is achieving increasing attention. The scientific understanding has increased substantially in the last decades, and a general consensus now seems to have been acieved that concentration...... the likelihood of them being present in environmentally found mixtures. Persistant, bioaccumulative and toxic (PBT) chemicals are therefore a highly relevant group of chemicals to consider for mixture toxicity regulation. The present study evaluates to what extent a number of PBT-like chemicals posess concern...

  4. Relativistic mixtures of charged and uncharged particles

    Science.gov (United States)

    Kremer, Gilberto M.

    2014-01-01

    Mixtures of relativistic gases within the framework of Boltzmann equation are analyzed. Three systems are considered. The first one refers to a mixture of uncharged particles by using Grad's moment method, where the relativistic mixture is characterized by the moments of the distribution functions: particle four-flows, energy-momentum tensors, and third-order moment tensors. In the second Fick's law for a mixture of relativistic gases of non-disparate rest masses in a Schwarzschild metric are derived from an extension of Marle and McCormack model equations applied to a relativistic truncated Grad's distribution function, where it is shown the dependence of the diffusion coefficient on the gravitational potential. The third one consists in the derivation of the relativistic laws of Ohm and Fourier for a binary mixtures of electrons with protons and electrons with photons subjected to external electromagnetic fields and in presence of gravitational fields by using the Anderson and Witting model of the Boltzmann equation.

  5. Organochlorine Pesticides (OCs) and Polychlorinated Biphenyls (PCBs) inTilapia zillii from Lake El-Manzala Egypt

    International Nuclear Information System (INIS)

    A fishwater fish species, (Tilapia zillii) from Lake El-Manzala was analyzed for concentrations of several Organochlorine pesticides (OCs) and Polychlorinated biphenyls (PCBs) in liver, gonads, mesenteric fat, flesh and the digestive tract in the mature fish during the breeding season. Polychlorinated pesticides (OCs) were calculated in (ng/g) dry weight (dw) in homogenized samples. The obtained results revealed differences in lipid content between these different organs. The females showed higher lipid content than males. There was significant positive correlation between the lipid content and organochlorines and polychlorinated biphenyls (PCBs). The results came concomitant with the lipophilicity of studied compounds. However, the recorded concentrations of these studied pollutants still do not exceed the international hazardous levels. (author)

  6. Poly(meta-phenylene) Derivative with Rigid Twisted Biphenyl Units in Backbone: Synthesis, Structural Characterization,Photophysical Properties and Electroluminescence

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yan; YANG Bing; ZHANG Hai-quan; LU Ping; SHEN Fang-zhong; LIU Lin-lin; XU Hai; YANG Guang-di; MA Yu-guang

    2007-01-01

    A soluble poly(meta-phenylene) derivative with rigid twisted biphenyl unit was synthesized by the Yamamoto coupling reaction. The polymer is soluble in common organic solvents, and the number-average molecular weight is about 6500. The UV-Vis and quantum chemical calculation indicate that the different conformation segments named "conformers" exist in the polymer backbones; it was also further confirmed by the single crystal X-ray diffraction study of the dimeric model compound. The π-π* transition of biphenyl segments of twisted and planar conformations made the polymer exhibit a strong absorption around 256 nm and a weak absorption at about 300 nm. Furthermore,the polymer exhibits a strong UV photoluminescence at 372 nm when the excitation wavelengths are longer than 300 nm. The ultraviolet-emitting electroluminescence(EL) device with the single layer structure shows EL λmax of the derivative at 370 nm.

  7. Photoredox-Catalyzed Tandem Insertion/Cyclization Reactions of Difluoromethyl and 1,1-Difluoroalkyl Radicals with Biphenyl Isocyanides.

    Science.gov (United States)

    Zhang, Zuxiao; Tang, Xiaojun; Dolbier, William R

    2015-09-18

    Using visible-light photoredox conditions, difluoromethylation and 1,1-difluoroalkylation of biphenyl isocyanides have allowed the synthesis of a series of 6-(difluoromethyl)- and 6-(1,1-difluoroalkyl)phenanthridines via tandem addition/cyclization/oxidation processes. The reactions are carried out in wet dioxane at room temperature using fac-Ir(ppy)3 as catalyst to form a large variety of substituted phenanthridine products in good to excellent yield. PMID:26336815

  8. Exposure to polychlorinated biphenyls enhances lipid peroxidation in human normal peritoneal and adhesion fibroblasts: a potential role for myeloperoxidase

    OpenAIRE

    Saed, Ghassan M.; Jiang, Zhong L.; Fletcher, Nicole M.; Arab, Ali Al; Diamond, Michael P.; ABU-SOUD, HUSAM M.

    2010-01-01

    Nitric oxide (NO), superoxide and lipid peroxidation (LPO) produced under oxidative stress may contribute to development of postoperative adhesions. The objective of this study was to determine the effects of polychlorinated biphenyls (PCBs) on LPO, superoxide dismutase (SOD3), myeloperoxidase (MPO), and nitrite/nitrate in human normal peritoneal and adhesion fibroblasts. PCB treatment reduced iNOS expression as well as levels of nitrite/nitrate in both cell lines. Although there was no diffe...

  9. Fluorogenic derivatization of aryl halides based on the formation of biphenyl by Suzuki coupling reaction with phenylboronic acid.

    OpenAIRE

    Kishikawa, Naoya; Kubo, Kimiko; Hammad, Sherin Farouk; Mabrouk, Mokhtar Mohamed; Habib, Ahmed; Elfatatry, Hamed; Ohyama, Kaname; Nakashima, Kenichiro; Kuroda, Naotaka

    2009-01-01

    The fluorogenic derivatization method for aryl halide was developed for the first time. This method was based on the formation of fluorescent biphenyl structure by Suzuki coupling reaction between aryl halides and non-fluorescent phenylboronic acid (PBA). We measured the fluorescence spectra of the products obtained by the reaction of p-substituted aryl bromides (i.e., 4-bromobenzonitrile, 4-bromoanisole, 4-bromobenzoic acid ethyl ester and 4-bromotoluene) with PBA in the presence of palladiu...

  10. Developmental Coexposure to Polychlorinated Biphenyls and Polybrominated Diphenyl Ethers Has Additive Effects on Circulating Thyroxine Levels in Rats

    OpenAIRE

    Miller, Veronica M; Sanchez-Morrissey, Susana; Brosch, Karl O; Seegal, Richard F.

    2012-01-01

    Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are widespread environmental contaminants found in seafood and dairy products. PCBs and PBDEs are structurally similar chemicals and affect thyroid hormone function and behavior in children and laboratory rodents. Although coexposure frequently exists, the in vivo developmental effects of combined exposure to PCBs and PBDEs on thyroxine (T4) levels are unknown. We examined the effects of PCB and PBDE coexposure from g...

  11. Polychlorinated Biphenyls in Residential Soils and their Health Risk and Hazard in an Industrial City in India

    OpenAIRE

    Bhupander Kumar; Virendra Kumar Verma; Satish Kumar Singh; Sanjay Kumar; Chandra Shekhar Sharma; Akolkar, Avinash B.

    2014-01-01

    Background Polychlorinated biphenyls (PCBs) have never been produced in India, but were used in industrial applications. PCBs have been detected in environmental samples since 1966, and their sources in soils come from depositions of industrial applications, incinerators and biomass combustions. PCBs adsorb to soil particles and persist for long time due to their properties. Their close proximity may also lead to human exposure through ingestion, inhalation, dermal contact, and may exert neur...

  12. Evidence of an Age Related Threshold Effect of Polychlorinated Biphenyls (PCBs) on Neuropsychological Functioning in a Native American Population

    OpenAIRE

    Haase, Richard F.; McCaffrey, Robert J.; Santiago-Rivera, Azara L.; Morse, Gayle S.; Tarbell, Alice

    2008-01-01

    Polychlorinated biphenyls (PCBs) have been suspected for some time of having adverse effects on neuropsychological functioning in humans. While there is evidence of slowing of cognitive function in children associated with exposure to PCBs, the evidence of comparable effects on adults is far less well understood. We report here on the neuropsychological evaluation of 277 Native American adults, ranging in age from 18 -79, who were exposed to PCBs by way of environmental contamination in the S...

  13. Determinants of Prenatal Exposure to Polychlorinated Biphenyls (PCBs) and Polybrominated Diphenyl Ethers (PBDEs) in an Urban Population

    OpenAIRE

    Herbstman, Julie B.; Sjödin, Andreas; Apelberg, Benjamin J.; Witter, Frank R.; Patterson, Donald G.; Halden, Rolf U.; Jones, Richard S.; Park, Annie; Zhang, Yalin; Heidler, Jochen; Needham, Larry L.; Goldman, Lynn R.

    2007-01-01

    Background Recent studies have reported blood levels of polybrominated diphenyl ethers (PBDEs) in the U.S. population. Information about neonatal levels and about the relationship to polychlorinated biphenyls (PCBs) exposures is limited. Objectives The objective was to characterize levels and determinants of fetal exposure to PBDEs and PCBs among newborns from Baltimore, Maryland. Methods We analyzed umbilical cord blood for eight PBDEs and 35 PCBs from infants delivered at the Johns Hopkins ...

  14. Fate and transport of planar and mono-ortho polychlorinated biphenyls and polychlorinated naphthalenes in Southern California sediments

    OpenAIRE

    Venkatesan, M. Indira

    2003-01-01

    Polychlorinated biphenyls (PCBs) are an important class of industrial pollutants that areubiquitous in the marine and freshwater environments (NAS, 1979). Although the “planar” or“non-ortho” PCB congeners are present in much lower concentrations than other PCBcongeners, they can be responsible for much of the dioxin-like (TCDD) toxicity in the marineecosystem. Further, their environmental fate may be different from other PCBs. Theirdetermination is, therefore, crucial for assessment of contam...

  15. Mass spectrometry analysis of polychlorinated biphenyls: chemical ionization and selected ion chemical ionization using methane as a reagent gas

    OpenAIRE

    RAYMOND E. MARCH; MILA D. LAUSEVIC; TATJANA M. VASILJEVIC

    2000-01-01

    In the present paper a quadrupole ion trap mass spectrometer, coupled with a gas chromatograph, was used to compare the electron impact ionization (EI) and chemical ionization (Cl) technique, in terms of their selectivity in polychlorinated biphenyls (PCBs) quantitative analysis. The experiments were carried out with a modified Varian SATURN III quadrupole ion-storage mass spectrometer equipped with Varian waveform generator, coupled with a gas chromatograph with DB-5 capillary column. The di...

  16. Effects of Polychlorinated Biphenyls on the Development of Neuronal Cells in Growth Period; Structure-Activity Relationship

    OpenAIRE

    Do, Youngrok; Lee, Dong Kuck

    2012-01-01

    Polychlorinated biphenyls (PCBs) are accumulated in our body through food chain and cause a variety of adverse health effects including neurotoxicities such as cognitive deficits and motor dysfunction. In particular, neonates are considered as a high risk group for the neurotoxicity of PCBs exposure. The present study attempted to analyze the structure-activity relationship among PCB congeners and the mechanism of PCBs-induced neurotoxicity. We measured total protein kinase C (PKC) activities...

  17. Effect of Socioeconomic Status on Exposures to Polychlorinated Biphenyls (PCBs) and Dichlorodiphenyldichloroethylene (DDE) among Pregnant African-American Women

    OpenAIRE

    Borrell, Luisa N.; Factor-Litvak, Pam; Wolff, Mary S.; Susser, Ezra; Matte, Thomas D

    2004-01-01

    In this study, the authors investigated the associations between socioeconomic status and exposures to polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (DDE) in a cohort of inner-city African-American pregnant women. Data for this study were derived from the Columbia Presbyterian Medical Center subcohort of the National Collaborative Perinatal Project. African-American women from whom venous blood had been collected during their third trimester of pregnancy during the tim...

  18. Polychlorinated Biphenyls (PCBs) Enhance Metastatic Properties of Breast Cancer Cells by Activating Rho-Associated Kinase (ROCK)

    OpenAIRE

    Du, Yuguo; Li, Shitao; Liu, Sijin

    2010-01-01

    Background: Polychlorinated biphenyls (PCBs) are a family of structurally related chlorinated aromatic hydrocarbons. Numerous studies have documented a wide spectrum of biological effects of PCBs on human health, such as immunotoxicity, neurotoxocity, estrogenic or antiestrogenic activity, and carcinogensis. The role of PCBs as etiologic agents for breast cancer has been intensively explored in a variety of in vivo, animal and epidemiologic studies. A number of investigations indicated that h...

  19. Contamination of Runoff Water at Gdańsk Airport (Poland) by Polycyclic Aromatic Hydrocarbons (PAHs) and Polychlorinated Biphenyls (PCBs)

    OpenAIRE

    Jacek Namieśnik; Anna Maria Sulej; Żaneta Polkowska

    2011-01-01

    Airport runoff can contain high concentrations of various pollutants, in particular polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), the environmental levels of which have to be monitored. Airport runoff water samples, collected at the Gdańsk-Rębiechowo Airport from 2008 to 2009, were analysed for PAHs and PCBs by gas chromatography. The aromatic fractions were separated by liquid-liquid extraction and analysed by GC/MS. Total PAH concentrations were 295–6,758 ng/...

  20. Polychlorinated Biphenyls in the Centralized Wastewater Treatment Plant in a Chemical Industry Zone: Source, Distribution, and Removal

    OpenAIRE

    Min Yao; Zhongjian Li; Xingwang Zhang; Lecheng Lei

    2014-01-01

    Polychlorinated biphenyls (PCBs) could be dissolved in wastewater or adsorbed on particulate. The fate of PCBs in wastewater is essential to evaluate the feasibility of wastewater treatment processes and the environmental risk. Here dissolved and adsorbed concentrations of twenty concerned PCB congeners and total PCBs have been measured in the centralized wastewater treatment plant of a chemical industry zone in Zhejiang, China. It was found that the dyeing chemical processes were the main so...

  1. Perinatal exposure to a noncoplanar polychlorinated biphenyl alters tonotopy, receptive fields, and plasticity in rat primary auditory cortex

    OpenAIRE

    Kenet, T; Froemke, R. C.; Schreiner, C. E.; Pessah, I N; Merzenich, M. M.

    2007-01-01

    Noncoplanar polychlorinated biphenyls (PCBs) are widely dispersed in human environment and tissues. Here, an exemplar noncoplanar PCB was fed to rat dams during gestation and throughout three subsequent nursing weeks. Although the hearing sensitivity and brainstem auditory responses of pups were normal, exposure resulted in the abnormal development of the primary auditory cortex (A1). A1 was irregularly shaped and marked by internal nonresponsive zones, its topographic organization was grossl...

  2. Synthesis and anti-inflammatory-analgesic activity of 2',4'-difluoro-3-(carbamoyl)biphenyl-4-yl benzoates

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Eighteen 2',4'-difluoro-3-(carbamoyl)biphenyl-4-yl benzoates were synthesized from diflunisal in three steps with total yields from 72% to 86%. All compounds were identified by IR, 1H NMR, MS and elemental analysis. The anti-inflammatory activity and analgesic activity for 18 compounds were evaluated. The preliminary assay results showed that compounds 4a and 4p exhibited potent anti-inflammatory-analgesic activity.

  3. Rapid Detection of Polychlorinated Biphenyls at Trace Levels in Real Environmental Samples by Surface-Enhanced Raman Scattering

    Directory of Open Access Journals (Sweden)

    Zhengjun Zhang

    2011-11-01

    Full Text Available Detection of trace levels of persistent pollutants in the environment is difficult but significant. Organic pollutant homologues, due to their similar physical and chemical properties, are even more difficult to distinguish, especially in trace amounts. We report here a simple method to detect polychlorinated biphenyls (PCBs in soil and distilled spirit samples by the surface-enhanced Raman scattering technique using Ag nanorod arrays as substrates. By this method, polychlorinated biphenyls can be detected to a concentration of 5 μg/g in dry soil samples within 1 minute. Furthermore, based on simulation and understanding of the Raman characteristics of PCBs, we recognized homologues of tetrachlorobiphenyl by using the surface-enhance Raman scattering method even in trace amounts in acetone solutions, and their characteristic Raman peaks still can be distinguished at a concentration of 10-6 mol/L. This study provides a fast, simple and sensitive method for the detection and recognition of organic pollutants such as polychlorinated biphenyls.

  4. Expression of Biphenyl Synthase Genes and Formation of Phytoalexin Compounds in Three Fire Blight-Infected Pyrus communis Cultivars.

    Directory of Open Access Journals (Sweden)

    Cornelia Chizzali

    Full Text Available Pear (Pyrus communis is an economically important fruit crop. Drops in yield and even losses of whole plantations are caused by diseases, most importantly fire blight which is triggered by the bacterial pathogen Erwinia amylovora. In response to the infection, biphenyls and dibenzofurans are formed as phytoalexins, biosynthesis of which is initiated by biphenyl synthase (BIS. Two PcBIS transcripts were cloned from fire blight-infected leaves and the encoded enzymes were characterized regarding substrate specificities and kinetic parameters. Expression of PcBIS1 and PcBIS2 was studied in three pear cultivars after inoculation with E. amylovora. Both PcBIS1 and PcBIS2 were expressed in 'Harrow Sweet', while only PcBIS2 transcripts were detected in 'Alexander Lucas' and 'Conference'. Expression of the PcBIS genes was observed in both leaves and the transition zone of the stem; however, biphenyls and dibenzofurans were only detected in stems. The maximum phytoalexin level (~110 μg/g dry weight was observed in the transition zone of 'Harrow Sweet', whereas the concentrations were ten times lower in 'Conference' and not even detectable in 'Alexander Lucas'. In 'Harrow Sweet', the accumulation of the maximum phytoalexin level correlated with the halt of migration of the transition zone, whereby the residual part of the shoot survived. In contrast, the transition zones of 'Alexander Lucas' and 'Conference' advanced down to the rootstock, resulting in necrosis of the entire shoots.

  5. Identification of a novel dimethoxylated polybrominated biphenyl bioaccumulating in marine mammals

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, G.; Athanasiadou, M.; Bergman, Aa.; Athanassiadis, I. [Department of Environmental Chemistry, Stockholm (Sweden); Endo, Tetsuya [Health Sciences Univ. of Hokkaido (Japan). Fac. of Pharmaceutical Sciences; Haraguchi, Koichi [Daiichi College of Pharmaceutical Sciences, Fukuoka (Japan)

    2004-09-15

    The screening of persistent halogenated organic pollutants has in recent years ended up with findings of numerous compounds being natural products. These compounds have preferably been reported from the marine environment and comprise, several hydroxylated and methoxylated polybrominated diphenyl ethers (OH-PBDEs and MeO-PBDEs) including monochlorinated ditto, a dimethoxylated polybrominated diphenyl ether i.e. 2',6-dimethoxy-2,3',4,5'-tetrabromodiphenyl ether, four halogenated dimethylated bipyrroles (HDBPs) with a 2,2'-bipyrrole backbone, a heptachlorinated 1,2'-bipyrrole i.e. heptachloro-1'-methyl-1,2'-bipyrrole (Q1)6 and a halogenated monoterpene holding two bromine and three chlorine atoms. We have taken interest in an organobrominated compound with an unknown structure but with a molecule ion of m/z = 526 and a four bromine isotope pattern according to mass spectrometry (MS), detected in marine mammal samples of which the majority were collected from Japanese coastal waters. This compound has recently been reported from several marine mammals collected on the Southern hemisphere, but neither the chemical structure nor the type of substance group were established. We here report the structure of this organobrominated compound, a dimethoxylated polybrominated biphenyl, which likely is of natural origin. The identification was done by the comparison of relative retention time (RRT) on two GC columns with different polarities and by comparing mass spectra from three different ionization techniques i.e. PICI, ECNI and EI, of the unknown compound from the samples with an authentic reference compound. Levels of the novel dimethoxylated polybrominated biphenyl are reported as well as the levels (for comparison) of some other known polybrominated compounds, both brominated flame retardants (BFRs) and natural products i.e. BDE-47, BDE-99, BDE-100, BDE-153, BDE-154, BDE-183, 1,2,5,6,9,10- hexabromocyclododecane (HBCDD), 6-MeO-BDE-47, 2

  6. On the mixture model for multiphase flow

    Energy Technology Data Exchange (ETDEWEB)

    Manninen, M.; Taivassalo, V. [VTT Energy, Espoo (Finland). Nuclear Energy; Kallio, S. [Aabo Akademi, Turku (Finland)

    1996-12-31

    Numerical flow simulation utilising a full multiphase model is impractical for a suspension possessing wide distributions in the particle size or density. Various approximations are usually made to simplify the computational task. In the simplest approach, the suspension is represented by a homogeneous single-phase system and the influence of the particles is taken into account in the values of the physical properties. This study concentrates on the derivation and closing of the model equations. The validity of the mixture model is also carefully analysed. Starting from the continuity and momentum equations written for each phase in a multiphase system, the field equations for the mixture are derived. The mixture equations largely resemble those for a single-phase flow but are represented in terms of the mixture density and velocity. The volume fraction for each dispersed phase is solved from a phase continuity equation. Various approaches applied in closing the mixture model equations are reviewed. An algebraic equation is derived for the velocity of a dispersed phase relative to the continuous phase. Simplifications made in calculating the relative velocity restrict the applicability of the mixture model to cases in which the particles reach the terminal velocity in a short time period compared to the characteristic time scale of the flow of the mixture. (75 refs.)

  7. Assessing exposures to inhaled complex mixtures.

    OpenAIRE

    Leaderer, B P; Lioy, P J; Spengler, J D

    1993-01-01

    In the course of daily activities, individuals spend varying amounts of time in different spaces where they are exposed to a complex mixture of gas, vapor, and particulate contaminants. The term complex is used in this paper to refer to binary mixtures as well as truly complex mixtures of three or more constituents. The diversity of the environments where pollution may occur, the number of pollutants that may be present, and the nature of the activity in the environment combine to pose a chal...

  8. Correlation of the liquid mixture viscosities

    Directory of Open Access Journals (Sweden)

    Knežević-Stevanović Anđela B.

    2012-01-01

    Full Text Available In this paper forty two selected correlation models for liquid mixture viscosities of organic compounds were tested on 219 binary and 41 ternary sets of experimental data taken from literature. The binary sets contained 3675 experimental data points for 70 different compounds. The ternary sets contained 2879 experimental data points for 29 different compounds. The Heric I, Heric-Brewer II, and Krishnan-Laddha models demonstrated the best correlative characteristics for binary mixtures (overall absolute average deviation < 2%. The Heric I, Heric-Brewer II, Krishnan-Laddha and Heric II models demonstrated the best correlative characteristics for ternary mixtures (overall absolute average deviation < 3%.

  9. Adsorption on mixtures of ion exchangers

    International Nuclear Information System (INIS)

    A theoretical study has been made of adsorption on mixtures of ion exchangers. The effect of variables such as the concentration of the ion being adsorbed, the concentration of the supporting electrolyte, loading, the values of the capacities and equilibrium constants for the various exchange processes, and the fraction of each adsorber in the mixture on the observed distribution coefficient has been investigated. A computer program has been written to facilitate the calculation of distribution coefficients for the adsorption of an ion on a given mixture of ion exchangers under a specified set of conditions

  10. Preparation of Aryl-Substituted Sulfonium by Condensation of Biphenyl Sulfoxides with Aromatic Compound%二苯亚砜与芳族化合物缩合制备芳取代三苯基硫鎓盐

    Institute of Scientific and Technical Information of China (English)

    刘安昌; 莫健华; 黄树槐; 邹菁

    2005-01-01

    Three kind of aryl-substituted tri-benzyl sulfonium salts [ (4-phX) phSph2 ] PF6 [ X = S, O ] were prepared by the condensation of biphenyl sulfoxide with biphenyl sulfide, biphenyl ether or 1,1' -biphenyl in the presence of polyphosphoric acid which can be used as dehydrate agent. The reaction condition was mild, such as reaction temperature between 40 - 50 ℃, reactive time 2 - 3 h, the yield of 4-(phenylthio)triphenylsulfonium hexafluorophosphate was 87.6 %. The three kind sulfonium salts show better curing character to epoxy resin.

  11. Biofilms at work: Bio-, phyto- and rhizoremediation approaches for soils contaminated with polychlorinated biphenyls

    Directory of Open Access Journals (Sweden)

    Merily Horwat

    2015-09-01

    Full Text Available Organohalide contaminants such as polychlorinated biphenyls (PCBs have been released into the environment for decades due to anthropogenic activities, but are also naturally produced in small amounts through volcanic eruptions and geochemical processes. Although toxic to humans and other organisms, the natural production of these compounds has resulted in the evolution of naturally occurring organohalide-respiring bacteria that possess the enzymes necessary to degrade PCB compounds to non-toxic products. The efficiency of PCB degradation can be improved by facilitating the formation of organohalide-respiring biofilms. During biofilm colonization on a surface or interface, bacteria are encased in an extracellular polymeric substance (EPS or “slime,” which allows them to share nutrients and remain protected from environmental stresses. Effective bioremediation of PCBs involves facilitation of biofilm growth to promote cooperation between bacteria, which can be further enhanced by the presence of certain plant species. This review aims to give an overview of biofilm processes involved in the detoxification of PCBs including anaerobic and aerobic PCB degradation by bacteria as well as the ability of plants to stimulate microbial activity and degradation (rhizoremediation and phytoremediation.

  12. Spatial distribution of polychlorinated biphenyls, organochlorine pesticides, and dechlorane plus in Northeast Asia

    Science.gov (United States)

    Baek, Song-Yee; Jurng, Jongsoo; Chang, Yoon-Seok

    2013-01-01

    XAD-2 resin-based passive air samplers (PAS) were deployed for one year at eight cities in Mongolia, China, and South Korea to investigate the spatial distribution of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and dechlorane plus (DP). PCB levels were highly correlated with population size and density in China and South Korea. In Mongolia, PCB levels were relatively high considering the low population. In the cases of OCPs and DP, a country-specific distribution was observed. The highest levels of HCHs (hexachlorocyclohexane isomers) and DDTs (dichlorodiphenyl trichloroethane isomers) were detected at sites in China, whereas the highest endosulfan and DP levels were measured at South Korean sites. These results strongly reflected the patterns of use of these chemicals. Mirex, an insecticide never registered in Mongolia and South Korea, was detected at all sampling sites; this is likely to have resulted from long-range transport. Nevertheless, OCPs were generally low in Mongolia. This study confirms that PAS results reflect well the past and current usage of POPs in Northeast Asia.

  13. The uridine diphosphate glucuronosyltransferases: quantitative structure-activity relationships for hydroxyl polychlorinated biphenyl substrates

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Degao [Dalian University of Technology, Department of Environmental Science and Technology, Dalian (China)

    2005-10-01

    Quantitative structure-activity relationships (QSARs), which relate the glucuronidation of hydroxyl polychlorinated biphenyls (OH-PCBs) - catalyzed by the uridine diphosphate glucuronosyltransferases (UGTs) - to their physicochemical properties and molecular structural parameters, can be used to predict the rate constants and interpret the mechanism of glucuronidation. In this study, QSARs have been developed that use 23 semi-empirical calculated quantum chemical descriptors to predict the logarithms of the constants 1/K{sub m} and V{sub max}, related to enzyme kinetics. A partial least squares regression method was used to select the optimal set of descriptors to minimize the multicollinearity between the descriptors, as well as to maximize the cross-validated coefficient (Q{sup 2} {sub cum}) values. The key descriptors affecting log(1/K{sub m}) were E{sub lumo}- E{sub homo} (the energy gap between the lowest unoccupied molecular orbital and the highest occupied molecular orbital) and q{sub C}{sup -} (the largest negative net atomic charge on a carbon atom), while the key descriptors affecting log V{sub max} were the polarizability {alpha}, the Connolly solvent-excluded volume (CSEV), and logP (the logarithm of the partition coefficient for octanol/water). From the results obtained it can be concluded that hydrophobic and electronic aspects of OH-PCBs are important in the glucuronidation of OH-PCBs. (orig.)

  14. Structural insights into the metabolism of 2-chlorodibenzofuran by an evolved biphenyl dioxygenase

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Pravindra; Mohammadi, Mahmood; Dhindwal, Sonali; Pham, Thi Thanh My; Bolin, Jeffrey T.; Sylvestre, Michel (INRS); (IIT-India); (Purdue)

    2012-06-28

    The biphenyl dioxygenase of Burkholderia xenovorans LB400 (BphAE{sub LB400}) is a Rieske-type oxygenase that catalyzes the stereospecific oxygenation of many heterocyclic aromatics including dibenzofuran. In a previous work, we evolved BphAE{sub LB400} and obtained BphAE{sub RR41}. This variant metabolizes dibenzofuran and 2-chlorodibenzofuran more efficiently than BphAE{sub LB400}. However, the regiospecificity of BphAE{sub RR41} toward these substrates differs. Dibenzofuran is metabolized principally through a lateral dioxygenation whereas 2-chlorodibenzofuran is metabolized principally through an angular dioxygenation. In order to explain this difference, we examined the crystal structures of both substrate-bound forms of BphAE{sub RR41} obtained under anaerobic conditions. This structure analysis, in combination with biochemical data for a Ser283Gly mutant provided evidences that the substrate is compelled to move after oxygen-binding in BphAE{sub RR41}:dibenzofuran. In BphAE{sub RR41}:2-chlorodibenzofuran, the chlorine atom is close to the side chain of Ser283. This contact is missing in the BphAE{sub RR41}:dibenzofuran, and strong enough in the BphAE{sub RR41}:2-chlorodibenzofuran to help prevent substrate movement during the catalytic reaction.

  15. Levels and Distribution of Polychlorinated Biphenyls in Jeddah Coastal Sediments, Red Sea, Saudi Arabia

    International Nuclear Information System (INIS)

    Thirty sediment samples were collected from six sites in Jeddah coast, Red Sea to assess the concentration levels of polychlorinated biphenyls (PCBs). Concentrations of 19 PCBs at the study area were ranged from 0.58 to 15.63 ng/g dry weight. The highest concentrations were recorded in the semi closed lagoons Al-Shabab and Al-Arbaeen (sites 4 and 5) which are highly influenced by sewage dumping. Textural classification of the sediments was found to be highly correlated with PCBs concentrations. PCB congener = 87 (penta-CB) showed the highest concentration among the 19 PCBs congeners. The descending order of different PCBs congeners was: penta-CB and gt; tetra-CB and gt; hexa-CB and gt; mono-CB and gt; tri-CB and gt; hepta-CB and gt; nona-CB. The medium PCBs congeners penta-, tetra- and hexa-CBs represented the major components at all sites. Aerobic and anaerobic environmental conditions change the homologue percentage in all stations. The contamination levels of PCBs in all sites were found to be below the two common sediment quality guidelines; the effects range-low value (ERL) and the threshold effects level (TEL). (author)

  16. Effects of liver damage induced by polychlorinated biphenyls (PCB) on cadmium metabolism in mice

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCB) were added to the diets of mice at different concentrations. Mice fed these diets were given a sc or oral doses of 109Cd. The uptake and excretion of Cd was followed by whole-body counting. The gastrointestinal absorption of Cd after an oral dose of 109Cd was less in animals fed on 66 ppm PCB diet, compared with a control group, and the body elimination of Cd was faster. In the liver, the amount of Cd was reduced by dietary PCB exposure, after both oral and sc administration of 109Cd, and the data suggest a faster transport of Cd from liver to kidneys in PCB-exposed animals than in controls. The mobilized liver Cd was not quantitatively recovered in the kidneys, thus increased urinary excretion due to PCB exposure may have taken place. Histological examination of the livers revealed a dose-dependent induction of liver changes characterized by centrilobular enlargement of liver cells and centrilobular focal necroses. In four of eight livers from animals fed 200 ppm PCB for 32 weeks there were five liver cell tumors with cytological signs of malignancy. In the control group and in groups fed lower doses of PCB (10-100 ppm) no such tumors were found among 28 animals. The results support observations made with agents inducing acute liver damage, that liver damage increases the rate of redistribution of cadmium from the liver to the kidney

  17. Placental markers of human exposure to polychlorinated biphenyls and polychlorinated dibenzofurans

    International Nuclear Information System (INIS)

    These studies have evaluated biochemical changes in placentae from humans exposed to rice oil contaminated with polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs) in Taiwan. Placentae were obtained from nonsmoking women 4 to 5 years after the exposure had occurred. The exposed individuals ingested approximately 1 to 3 g PCBs and 5 mg PCDFs, and many exhibited symptoms characteristic of PCB poisoning. This disease was termed Yu-Cheng in Chinese. Based on data from experimental animals models, the authors examined a number of parameters in placentae from control and exposed women, including arylhydrocarbon hydroxylase (AHH) activity, cytochrome P-450 isozymes, epidermal growth factor (EGF) receptor binding properties and actions, and Ah receptor. They also quantified concentrations of various PCB and PCDF congeners known to be present in the contaminated rice oil. The results revealed a dramatic elevation in placental AHH activity in samples from PCB/PCDF-exposed women. This increase in enzyme activity was associated with a parallel increase in placental microsomal protein immunochemically related to cytochrome P-450 form 6. EGF receptor-mediated autophosphorylation capacity was significantly diminished in PCB/PCDF placentae, but this effect was not associated with changes in plasma membrane EGF receptor binding properties. Two PCDF congeners were detected in Yu-Cheng placentae but not controls. Several PCBs were also detected in much higher concentrations in Yu-Cheng placentae. Surprisingly, placental concentrations of PCBs correlated better with effects than did the PCDFs. The findings are discussed in relation to the risk assessment process

  18. Vertical distribution of polychlorinated biphenyl congeners in sediment core from Thane Creek area of Mumbai, India

    International Nuclear Information System (INIS)

    In recent years there has been a growing concern all over the globe about the marine pollution due to persistent organic pollutants. Sediments, which is an important component of marine environment can serve as sorbent or concentrator for various persistent organic pollutants including Polychlorinated Biphenyls (PCBs). Transport and fate of PCB congeners in sediment depends on their physicochemical characteristics. In this study, the depth profile of accumulated PCBs in Thane Creek sediments of Mumbai, India, was studied. The sediment core samples were collected using a gravity corer, processed and analysed for different PCB congeners. Analysis of PCBs in the sediment samples were carried out using gas chromatography system equipped with electron capture detector. The study on vertical distribution of PCBs in sediment could reflect the geochemical history including changes due to anthropogenic releases into the system. The surface segment shows the downward trend for these compounds, indicating slow phase out of PCBs after ban. The concentration and composition of different homologues varies at different depth. An attempt has also been made to find out the various sources of PCBs which could have contributed to these compounds by performing factor analysis over the observed concentrations of the PCB compounds in the core sediment.

  19. Management of the Polychlorinated Biphenyl Inventory in the Double Shell Tank (DST) System

    International Nuclear Information System (INIS)

    Some Double-Shell Tanks (DST) have received small quantities of PCBs in historic waste shipments. For this reason at least some DST waste has been determined to be PCB remediation waste by the U.S. Department of Energy, Office of River Protection (ORP) and the United States Environmental Protection Agency (EPA). This determination was documented on August 31, 2000 in the ''Framework Agreement for Management of Polychlorinated Biphenyls (PCBs) in Hanford Tank Waste'' (Boston, et al.). PCB remediation waste is a new category of waste promulgated in the 1998 revision to the Toxic Substances Control Act (TSCA) commonly called the Mega-Rule. The applicability of TSCA to tank farm waste resulted in the application of new requirements and the necessity to manage and track PCBs in tank waste. This document describes the principal methods of managing PCBs in the DST system. This document also describes waste acceptance criteria to be used in evaluating the acceptability of waste containing PCBs. The main purpose behind the transfer controls and PCB waste acceptance criteria is to ensure that the waste can be adequately treated in the Waste Treatment (vitrification) Plant. These criteria may change as additional information on the treatment plant's capability becomes available

  20. Primary source regions of polychlorinated biphenyls (PCBs) measured in the Arctic

    Science.gov (United States)

    Ubl, Sandy; Scheringer, Martin; Stohl, Andreas; Burkhart, John F.; Hungerbuhler, Konrad

    2012-12-01

    We investigate the source regions of the three polychlorinated biphenyl congeners (PCBs) 28, 101, and 180 measured at the Arctic stations Alert and Zeppelin, and at Birkenes, which is located in southern Norway. Although the Arctic is remote from the main use areas of these chemicals, PCBs have been found in Arctic air, seawater and biota, which has caused concerns for human and environmental health. We used 20-day backward calculations of the Lagrangian Particle Dispersion Model FLEXPART to identify the origin of air masses associated with the 20% highest and lowest measured PCB concentrations. At Birkenes, high concentrations are clearly associated with air masses arriving from known source regions (primarily in Europe and Russia), whereas low concentrations are correlated with atmospheric transport from regions with low primary emissions. At Zeppelin, the influence from known source regions is also enhanced when high PCB-28 and PCB-101 concentrations were measured. At Alert, in contrast, there is no clear link between high/low PCB concentrations and atmospheric transport from source/non-source regions. Additionally, we combined the atmospheric transport patterns with PCB emission data to identify important source regions and their seasonal variability. For the Arctic stations, Western Russia is the dominant source region for PCB-28 and PCB-101. Central Europe is the most important source region for PCB-180, but sources in the US contribute up to 15% to PCB-180 measured at Alert.