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Sample records for ah-active pcb congeners

  1. Relation among cytochrome P450, Ah-active PCB congeners and dioxin equivalents in pipping black- crowned night-heron embryos

    USGS Publications Warehouse

    Rattner, B.A.; Hatfield, J.S.; Melancon, M.J.; Custer, T.W.; Tillitt, D.E.

    1994-01-01

    Pipping black-crowned night-heron (Nycticorax nycticorax) embryos were collected from a relatively uncontaminated site (next to Chincoteague National Wildlife Refuge, VA) and three polluted sites (Cat Island, Green Bay, Lake Michigan, WI; Bair Island, San Francisco Bay, CA; West Marin Island, San Francisco Bay, CA). Hepatic cytochrome P450-associated monooxygenases and cytochrome P450 proteins, induced up to 85- fold relative to the reference site, were associated with concentrations of total polychlorinated biphenyls (PCBs) and 11 PCB congeners that are presumed to express toxicity through the arylhydrocarbon (Ah) receptor. Multiple regression revealed that up to 86% of the variation of cytochrome P450 measurements was accounted for by variation in the concentration of these PCB congeners. Toxic equivalents (TEQs) of sample extracts, predicted mathematically (summed product of PCB congener concentrations and toxic equivalency factors), and dioxin equivalents (TCDD-EQs), derived by bioassay (ethoxyresorufin-O-dealkylase activity of treated H4IIE rat hepatoma cells), were greatest in Cat Island samples. Cytochrome P450-associated monooxygenases and cytochrome P450 proteins were related to TEQs and TCDD-EQs; adjusted r super(2) often exceeded 0.5 for the relation among mathematically predicted TEQs and cytochrome P450 measurements. These data extend previous observations in heron embryos of an association between P450 and total PCB burdens to include Ah- active PCB congeners, and presumably other compounds, which interact similarly with the Ah receptor. Benzyloxyresorufin O-dealkylase, ethoxyresorufin O-dealkylase, and cytochrome P450 1A appear to be the most reliable measures of exposure to Ah-active PCB congeners in black-crowned night-heron embryos. These findings provide further evidence that cytochrome P450-associated parameters have considerable value as a biomarker for assessing environmental contamination of wetlands.

  2. Relation among cytochrome P450, AH-active PCB congeners and dioxin equivalents in pipping black-crowned night-heron embryos

    USGS Publications Warehouse

    Rattner, B.A.; Hatfield, J.S.; Melancon, M.J.; Custer, T.W.; Tillitt, D.E.

    1994-01-01

    Pipping black-crowned night-heron (Nycticorax nycticorax) embryos were collected from a relatively uncontaminated site (next to Chincoteague National Wildlife Refuge, VA) and three polluted sites (Cat Island, Green Bay, Lake Michigan, WI; Bair Island, San Francisco Bay, CA; West Marin Island, San Francisco Bay, CA). Hepatic cytochrome P-450-associated monooxygenases and cytochrome P-450 proteins, induced up to 85-fold relative to the reference site, were associated with concentrations of total polychlorinated biphenyls (PCBs) and 11 PCB congeners that are presumed to express toxicity through the arylhydrocarbon (Ah) receptor. Multiple regression revealed that up to 86% of the variation of cytochrome P450 measurements was accounted for by variation in the concentration of these PCB congeners. Toxic equivalents (TEQs) of sample extracts, predicted mathematically (summed product of PCB congener concentrations and toxic equivalency factors), and dioxin equivalents (TCDD-EQs), derived by bioassay (ethoxyresorufin-O-dealkylase activity of treated H4IIE rat hepatoma cells), were greatest in Cat Island samples. Cytochrome P450-associated monooxygenases and cytochrome P450 proteins were related to TEQs and TCDD-EQs; adjusted r-2 often exceeded 0.5 for the relation among mathematically predicted TEQs and cytochrome P450 measurements. These data extend previous observations in heron embryos of an association between P450 and total PCB burdens to include Ah-active PCB congeners, and presumably other compounds, which interact similarly with the Ah receptor. Benzyloxyresorufin O-dealkylase, ethoxyresorufin O-dealkylase, and cytochrome P450 1A appear to be the most reliable measures of exposure to Ah-active PCB congeners in black-crowned night-heron embryos. These findings provide further evidence that cytochrome P450-associated parameters have considerable value as a biomarker for assessing environmental contamination of wetlands.

  3. Atmospheric PCB congeners across Chicago

    PubMed Central

    HU, DINGFEI; LEHMLER, HANS-JOACHIM; MARTINEZ, ANDRES; WANG, KAI; HORNBUCKLE, KERI C.

    2010-01-01

    We have measured PCBs in 184 air samples collected at 37 sites in the city of Chicago using an innovative system of high-volume air samplers mounted on two health clinic vans. Here we describe results of sampling conducted from November 2006 to November 2007. The samples were analyzed for all 209 PCB congeners using a gas chromatograph with tandem mass spectrometry (GC-MS/MS). The ΣPCBs (sum of 169 peaks) in Chicago ranged from 75 pg m−3 to 5500 pg m−3 and primarily varied as a function of temperature. The congener patterns are surprisingly similar throughout the city even though the temperature-corrected concentrations vary by more than an order of magnitude. The average profile resembles a mixture of Aroclor 1242 and Aroclor 1254, and includes many congeners that have been identified as being aryl hydrocarbon receptor (AhR) agonists (dioxin-like) and/or neurotoxins. The toxic equivalence (TEQ) and neurotoxic equivalence (NEQ) in air were calculated and investigated for their spatial distribution throughout the urban-industrial complex of Chicago. The NEQ concentrations are linearly correlated with ΣPCBs while the TEQ concentrations are not predictable. The findings of this study suggest that airborne PCBs in Chicago are widely present and elevated in residential communities; there are multiple sources rather than one or a few locations of very high emissions; the emission includes congeners associated with dioxin-like and neurotoxic effects and congeners associated with unidentified sources. PMID:21918637

  4. Variation in net trophic transfer efficiencies among 21 PCB congeners

    SciTech Connect

    Madenjian, C.P.; Schmidt, L.J.; Chernyak, S.M.; Elliott, R.F.; Desourcie, T.J.; Quintal, R.T.; Begnoche, L.J.; Hesselberg, R.J.

    1999-11-01

    The authors tested the hypothesis that the efficiency with which fish retain polychlorinated biphenyl (PCB) congeners from their food strongly depends on K{sub ow} and degree of chlorination of the congener. The authors used diet information, determinations of concentrations of individual PCB congeners in both coho salmon (Oncorhynchus kisutch) and their prey, and bioenergetics modeling to estimate the efficiencies with which Lake Michigan coho salmon retain various PCB congeners from their food. The retention efficiency for the tetrachloro congeners averaged 38%, whereas retention efficiencies for higher chlorinated congeners ranged from 43 to 56%. Not including tetrachloro congeners, the authors found neither decreasing nor increasing trends in the efficiencies with which the coho salmon retained the PCB congeners from their food with either increasing K{sub ow} or increasing degree of chlorination of the PCB congeners. The authors concluded that (a) for PCB congeners with 5--8 chlorine atoms/molecule, K{sub ow} and degree of chlorination had little influence on the efficiency with which coho salmon retained the various PCB congeners in their food, and (b) the efficiency with which coho salmon retained tetrachloro PCB congeners in their food appeared to be slightly lower than that for higher chlorinated PCB congeners.

  5. Variation in net trophic transfer efficiencies among 21 PCB congeners

    USGS Publications Warehouse

    Madenjian, C.P.; Schmidt, L.J.; Chernyak, S.M.; Elliott, R.F.; Desorcie, T.J.; Quintal, R.T.; Begnoche, L.J.; Hesselberg, R.J.

    1999-01-01

    We tested the hypothesis that the efficiency with which fish retain polychlorinated biphenyl (PCB) congeners from their food strongly depends on Kow and degree of chlorination of the congener. We used diet information, determinations of concentrations of individual PCB congeners in both coho salmon (Oncorhynchus kisutch) and their prey, and bioenergetics modeling to estimate the efficiencies with which Lake Michigan coho salmon retain various PCB congeners from their food. The retention efficiency for the tetrachloro congeners averaged 38%, whereas retention efficiencies for higher chlorinated congeners ranged from 43 to 56%. Not including tetrachloro congeners, we found neither decreasing nor increasing trends in the efficiencies with which the coho salmon retained the PCB congeners from their food with either increasing Kow or increasing degree of chlorination of the PCB congeners. We concluded that (a) for PCB congeners with 5−8 chlorine atoms/molecule, Kow and degree of chlorination had little influence on the efficiency with which coho salmon retained the various PCB congeners in their food, and (b) the efficiency with which coho salmon retained tetrachloro PCB congeners in their food appeared to be slightly lower than that for higher chlorinated PCB congeners.

  6. Serum PCB levels and congener profiles among US construction workers

    PubMed Central

    Herrick, Robert F; Meeker, John D; Hauser, Russ; Altshul, Larisa; Weymouth, George A

    2007-01-01

    Background The presence of PCB in caulking (sealant) material found in masonry buildings has been well-documented in several countries. A recent investigation of 24 buildings in the greater Boston area found that 8 buildings had high PCB levels in caulking materials used around window frames and in joints between masonry blocks. Workers removing caulking material have been shown to have elevated serum PCB levels. Methods This project compared serum PCB levels among male workers who installed and/or removed PCB-containing caulking material from buildings in the greater Boston area with reference serum PCB levels from 358 men from the same area. Serum PCB levels were measured in the same laboratory by liquid-liquid extraction, column chromatography clean-up and dual capillary column GC/microECD analysis. Results When the congener profiles were compared between the reference population and the construction workers, the serum levels of the more volatile, lighter PCBs (di-, tri-and tetrachloro, sum of IUPAC# 6–74) were substantially higher among the construction workers. One of the youngest workers had the lowest total serum PCB levels (sum of 57 congeners) of all 6 workers, but the contribution of more volatile (less chlorinated) PCB congeners (#16, 26,28,33,74,66, and 60) was markedly higher than in other 5 workers and reference men. Only this worker was working on a job that involved removing PCB caulking at the time of the blood sampling. Conclusion While the results of this pilot study are based upon small numbers (6 construction workers who handled PCB caulking), the serum PCB levels among the construction workers exceed the referents. Comparison of the congener profiles suggests that there are substantial differences between the construction workers and the general population samples. These differences, and the similarities of profiles among the construction workers strongly suggest that occupational contact with caulking material can be a major source of PCB

  7. PCB congener accumulation by periphyton, herbivores, and omnivores.

    PubMed

    Hill, W R; Napolitano, G E

    1997-05-01

    The concentrations of 20 polychlorinated biphenyl (PCB) congeners were measured in periphyton, herbivorous fish (stoneroller minnows, Campostoma anomalum), and omnivorous fish (striped shiners, Luxilus chrysocephalus) in an industrially contaminated stream and a reference stream in eastern Tennessee. The sum of the concentrations of the 20 congeners, normalized by dry mass, was one to two orders of magnitude higher in stonerollers and shiners than in periphyton. Normalizing PCB concentrations by lipid mass reduced concentration differences between periphyton and stonerollers, but PCBs per unit lipid in stonerollers were still 50-350% higher than those in periphyton. Shiners had significantly higher lipid-specific PCB concentrations than did stonerollers, so a trophic hierarchy of primary producer < herbivore < omnivore was evident in lipid-specific PCB concentrations. Differences in lipid type, exposure duration, and exposure sources may account for the trophic-level differences in total PCBs. Congener profiles were roughly similar in periphyton, stonerollers, and shiners: five congeners (IUPAC numbers 101, 110, 138, 153, and 180) constituted >60% of the total mass of PCBs analyzed in all three trophic levels. However, stoneroller and shiner tissue was enriched in congeners 153, 118, and 187 relative to periphyton; congeners 153 and 187 are resistant to metabolic breakdown by monooxygenases found in fish liver. Principal component analysis of congener percentages separated periphyton from fish and distinguished between sampling locations. PMID:9175515

  8. Analysis of PCB congeners related to cognitive functioning in adolescents.

    PubMed

    Newman, Joan; Gallo, Mia V; Schell, Lawrence M; DeCaprio, Anthony P; Denham, Melinda; Deane, Glenn D

    2009-07-01

    To investigate the characteristics of PCBs that are linked to cognitive functioning, those congeners that were concurrently found in 271 Mohawk adolescents were grouped according to structure (dioxin-like or non-dioxin-like) and persistence (persistent or low-persistent). After the effects of the congener groups were orthogonalized, regression analyses (controlling for a number of variables found to be related to the cognitive outcomes) examined the relationship of each congener group to scores on three cognitive tests (the non-verbal Ravens Progressive Matrices, the Test of Memory and Learning, and the Woodcock Johnson-Revised). Five subtests from these cognitive tests were found to be associated with one or more PCB congener groups, most often at a moderate level. Two measures of long-term memory (Delayed Recall and Long Term Retrieval) were associated with all four congener groups. Nevertheless, examination of the role of individual congeners in the significantly related congener groups revealed that almost all congeners associated with cognitive outcomes were non-dioxin-like and ortho-substituted. A notable exception was the Ravens test where scores were associated only with dioxin-like congeners. This finding adds to the limited evidence of neurotoxic effects of dioxin-like congeners. Auditory Processing was related only to the persistent congener group. The association of the non-persistent congener group with three cognitive test scores (Delayed Recall, Long Term Retrieval and Comprehension-Knowledge) suggests that the Mohawk adolescents have experienced continuing or recent environmental exposure to PCBs that is sufficient to result in detectable cognitive decrements. Comparison of our findings with those of other human studies was limited by the relative lack of specificity of both PCB measures and cognitive outcome measures in much previous work. PMID:19465051

  9. ANALYSIS OF PCB CONGENERS RELATED TO COGNITIVE FUNCTIONING IN ADOLESCENTS

    PubMed Central

    Newman, Joan; Gallo, Mia V.; Schell, Lawrence M.; DeCaprio, Anthony P.; Denham, Melinda; Deane, Glenn D.

    2011-01-01

    To investigate the characteristics of PCBs that are linked to cognitive functioning, those congeners that were concurrently found in 271 Mohawk adolescents were grouped according to structure (dioxin-like or non-dioxin-like) and persistence (persistent or low-persistent). After the effects of the congener groups were orthogonalized, regression analyses (controlling for a number of variables found to be related to the cognitive outcomes) examined the relationship of each congener group to scores on three cognitive tests (the non-verbal Ravens Progressive Matrices, the Test of Memory and Learning, and the Woodcock Johnson – Revised). Five subtests from these cognitive tests were found to be associated with one or more PCB congener groups, most often at a moderate level. Two measures of long term memory (Delayed Recall and Long Term Retrieval) were associated with all four congener groups. Nevertheless, examination of the role of individual congeners in the significantly related congener groups revealed that almost all congeners associated with cognitive outcomes were non-dioxin-like and ortho-substituted. A notable exception was the Ravens test where scores were associated only with dioxin-like congeners. This finding adds to the limited evidence of neurotoxic effects of dioxin-like congeners. Auditory Processing was related only to the persistent congener group. The association of the non-persistent congener group with three cognitive test scores (Delayed Recall, Long Term Retrieval and Comprehension-knowledge) suggests that the Mohawk adolescents have experienced continuing or recent environmental exposure to PCBs that is sufficient to result in detectable cognitive decrements. Comparison of our findings with those of other human studies was limited by the relative lack of specificity of both PCB measures and cognitive outcome measures in much previous work. PMID:19465051

  10. Comparative developmental toxicity of planar PCB congeners by egg injection

    SciTech Connect

    Hoffman, D.J.; Melancon, M.J.; Eisemann, J.D.; Klein, P.N.

    1995-12-31

    The utility of egg injection studies for predicting potential embryotoxicity of PCBs and TCDD compares favorably with feeding studies. The effects of PCB congeners 3,3{prime}4,4{prime}-tetraCB (PCB 77), 2,3,3{prime},4,4{prime}-pentaCB (PCB 105), 3,3{prime},4,4{prime},5-pentaCB (PCB 126) and 2,2{prime},4,4{prime},5,5{prime}-hexaCB (PCB 153) were examined on embryonic development in chickens (Gallus gallus), northern bobwhite (Colinus virginianus), American kestrels (Falco sparverius), and common terns (Sterna hirundo) through hatching following air cell injections on day 4. The estimated LD{sub 50}s for these congeners in chickens were approximately 0.4 ppb, 2.6 ppb, 3326 ppb, and greater than 14,000 ppb, respectively; low effect levels (10--20% embryonic mortality) were 0.2 ppb, 1.2 ppb, 900 ppb, and 14,000 ppb respectively. The estimated LD{sub 50} for PCB 126 was 48 ppb for bobwhite, 65 ppb for American kestrels, and 104 ppb for common terns. The estimated LD{sub 50} for PCB 77 was 688 ppb for American kestrels. one or more hepatic microsomal cytochrome P450-linked monooxygenases including ethoxyresorufin-O-deethylase was assayed for each species. For PCB 126, the order of responsiveness of cytochrome P450 induction was: chicken > common tern > American kestrel > bobwhite, with chicken being approximately 100 times more responsive than common tern. These values are compared to existing Toxic Equivalency Factors (TEFs) including bioassay-derived ones.

  11. PCB congeners in tissues of European otter (Lutra lutra)

    SciTech Connect

    Mason, C.F.; Ratford, J.R. )

    1994-10-01

    Otters (Lutra lutra) have declined over much of their European range during the past forty years and are now absent from large areas of the lowlands of Western Europe. The most likely cause of the decline is the effects of bioaccumulating contaminants, organochlorine pesticides and PCBs having been implicated. There have been several recent studies of organochlorine residues (pesticides and PCBs) in otter tissues and scats have been used to monitor residues in otter populations. However, only from The Netherlands have data on individual PCB congeners in otter tissues and scats been reported; this Dutch otter population is now extirpated. We report a survey of PCB congeners in samples of tissues and scats from several populations of otters. 21 refs., 3 tabs.

  12. Incubation stage and polychlorinated biphenyl (PCB) congener patterns in an altricial and precocial bird species

    USGS Publications Warehouse

    Custer, Christine M.; Custer, Thomas W.; Thyen, Stefan; Becker, Peter H.

    2014-01-01

    The composition of polychlorinated biphenyl (PCB) congeners was compared between non-incubated and embryonated eggs of tree swallows (Tachycineta bicolor) and little terns (Sterna albifrons) to determine if measurable changes in PCB congeners occurred during the embryonic period. There was no indication of changes in PCB congener patterns over the incubation period in tree swallows in 1999 and 2000 at a site with very high PCB exposure or a site with more modest PCB exposure. Additionally, congeners known to be either quickly metabolized or conserved based on experimental studies did not generally respond as predicted. Similarly, PCB congener patterns in eggs of little terns from Bottsand, Schleswig-Holstein, Germany, did not differ between non-incubated and embryonated eggs. The results from both species suggest that the stage of incubation is not an important consideration when evaluating PCB congener patterns; comparisons and assessments can be made with eggs collected at all stages of incubation.

  13. Incubation stage and polychlorinated biphenyl (PCB) congener patterns in an altricial and precocial bird species.

    PubMed

    Custer, Christine M; Custer, Thomas W; Thyen, Stefan; Becker, Peter H

    2014-12-01

    The composition of polychlorinated biphenyl (PCB) congeners was compared between non-incubated and embryonated eggs of tree swallows (Tachycineta bicolor) and little terns (Sterna albifrons) to determine if measurable changes in PCB congeners occurred during the embryonic period. There was no indication of changes in PCB congener patterns over the incubation period in tree swallows in 1999 and 2000 at a site with very high PCB exposure or a site with more modest PCB exposure. Additionally, congeners known to be either quickly metabolized or conserved based on experimental studies did not generally respond as predicted. Similarly, PCB congener patterns in eggs of little terns from Bottsand, Schleswig-Holstein, Germany, did not differ between non-incubated and embryonated eggs. The results from both species suggest that the stage of incubation is not an important consideration when evaluating PCB congener patterns; comparisons and assessments can be made with eggs collected at all stages of incubation. PMID:25213805

  14. Total PCBs and PCB congeners in Spanish Imperial Eagle eggs

    SciTech Connect

    Hernandez, L.M.; Fernandez, M.A.; Gonzalez, M.J. )

    1989-11-01

    The Spanish Imperial Eagle Aquila (heliaca) adalberti is the only directly endangered bird of prey in Europe. Lowered reproductive success in numerous bird species has been associated with eggshell thinning and reduced production caused by DDE, the most common organochlorine residue found in wild birds. Polychlorinated biphenyls (PCBs) are usually the second most common organochlorine pollutant found in wild birds. Research to evaluate the incidence of organochlorine pollutants in the Spanish Imperial Eagle has been previously conducted. The authors have now determined the levels of total PCBs and selected PCB congeners in 34 eggs of Spanish Imperial Eagle collected at Donana National Park, Castile Plateau and Nature Park of Monfrague, since this has considerable significance when attempts are made to correlate the embryonic mortality of avian wildlife with PCB residue levels.

  15. Formation of toxic PCB congeners and PCB-solvent adducts in a sunlight irradiated cyclohexane solution of aroclor 1254

    SciTech Connect

    Lepine, F.; Milot, S.; Vincent, N. )

    1992-01-01

    Photodegradation by sunlight is an important decomposition mechanism of polychlorinated biphenyls in the environment. Photodegradation of PCBs proceeds through successive dechlorination of the biphenyl nucleus and thus modify the proportions of the various congeners in a PCB mixture. The objectives of this work is to study the effects of sunlight on a typical PCB mixture such as Aroclor 1254, in a congener specific approach in order to observe the variations in the levels of these toxic congeners in the irradiated mixture.

  16. Generating the Right PCB Data: Determination of Aroclors Versus PCB Congeners

    SciTech Connect

    Prignano, A.L.; Narquis, C.T.; Hyatt, J.E.

    2008-07-01

    Polychlorinated biphenyls (PCBs) are a major environmental concern due to their ubiquity and tendency to bio-accumulate, as well as their persistence and toxicity. As the cleanup of waste and contaminated soil progresses at U.S. Department of Energy (DOE) sites, the costs for accurate PCB data are increasing. PCBs are actually a broad name for a group of 209 individual compounds known as congeners. PCBs were originally produced in the United States as specific mixtures of congeners known as Aroclors. PCBs can be analyzed and quantified either as Aroclor mixtures or as individual congeners. Aroclor analysis, which is the more common analytical method applied to PCBs, has been in use for decades, and in general, most cleanup regulations are based on total PCB concentrations using Aroclor analyses. Congener analysis is relatively new to environmental cleanup and restoration due to both technical issues and associated cost. The benefits of congener analysis are that it allows a more direct analysis of the risk of the PCBs. The World Health Organization (WHO) has identified twelve specific congeners as dioxin-like with toxicity ranging from 0.00003 to 0.1 times the standard 2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) toxicity. This paper defines Aroclors and congeners and compares the current application and usefulness of the two analytical methods for environmental restoration and cleanup. A strategy for the best use of the two methods to optimize overall characterization cost is presented. As part of the strategy, a method using the data from Aroclor analyses to calculate 2,3,7,8-TCDD toxicity equivalent concentrations is also presented. (authors)

  17. GENERATING THE RIGHT PCB DATA DETERMINATION OF AROCLORS VERSUS PCB CONGENERS

    SciTech Connect

    NARQUIS CT; PRIGNANO AL

    2007-11-21

    Polychlorinated biphenyls (PCBs) are a major environmental concern due to their ubiquity and tendency to bio-accumulate. as well as their persistence and toxicity. As the cleanup of waste and contaminated soil progresses at U.S. Department of Energy (DOE) sites, the costs for accurate PCB data are increasing. PCBs are actually a broad name for a group of 209 individual compounds known as congeners. PCBs were originally produced in the United States as specific mixtures of congeners known as Aroclors'. PCBs can be analyzed and quantified either as Aroclor mixtures or as individual congeners. Aroclor analysis, which is the more common analytical method applied to PCBs. has been in use for decades, and in general, most cleanup regulations are based on total PCB concentrations using Aroclor analyses. Congener analysis is relatively new to environmental cleanup and restoration due to both technical issues and associated cost. The benefits of congener analysis are that it allows a more direct analysis of the risk of the PCBs. The World Health Organization (WHO) has identified twelve specific congeners as dioxin-like with toxicity ranging from 0.00003 to 0.1 times the standard 2,3,7.8-Tetrachlorodibenzo-p-dioxin (2.3.7.8-TCDD) toxicity. This paper defines Aroclors and congeners and compares the current application and usefulness of the two analytical methods for environmental restoration and cleanup. A strategy for the best use of the two methods to optimize overall characterization cost is presented. As part of the strategy. a method using the data from Aroclor analyses to calculate 2,3,7,8-TCDD toxicity equivalent concentrations is also presented.

  18. Influence of cadmium on PCB congener accumulation in quail

    SciTech Connect

    Leonzio, C.; Marsili, L.; Focardi, S. )

    1992-11-01

    Technological development this century has led to an environmental input of synthetic chemical compounds totally extraneous to natural ecosystems such as Polychlorobiphenyls (PCBs), extensively used in agriculture and industry. These xenobiotics have a high fat/water repartition coefficient, making them easily accumulated by living organisms. Their persistence and low degradability means that they are now present throughout the global ecosystem. Ubiquitous environmental contaminants also include heavy metals like Hg, As, Pb, Cd and Cr, of which Cd, an element causing functional damage to the kidney and liver in which it preferentially accumulates, is of special ecotoxicological importance. The WHO has defined an accumulation of 60 mg/kg (fresh weight), beyond which damage occurs. Cd occurs [open quotes]naturally[close quotes] in high concentrations in certain animal species including molluscs. Birds and marine mammals feeding largely on cephalopods show high levels of this metal. Many monitoring studies have also revealed high concentrations of PCBs in the same animals. The vast majority of studies on contaminants in experimental animals consider the short-, medium- and long-term effects of a single pollutant. However, the presence of synergisms and antagonisms between compounds makes it necessary to adopt a more holistic approach to the problem of environmental pollution. In order to understand if the effect of xenobiotic compounds like PCBs may be potentiated by the natural presence of cadmium in bird population, we sought preliminary information on how the presence of cadmium in the diet may influence the accumulation and metabolization of PCB congeners. The influence of Cd on PCB accumulation was investigated in Japanese quail treated experimentally with Cd and PCBs. Particular attention was paid to final congener accumulation and qualitative differences in congener composition between controls and treated birds. 15 refs., 3 figs., 1 tab.

  19. Stepping backward to improve assessment of PCB congener toxicities.

    PubMed Central

    Hansen, L G

    1998-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitous global contaminants that have been intensively investigated for three decades. They are broad-acting toxicants occurring in complex mixtures and accurate risk assessment has proven to be elusive. Focusing on a limited set of end points and emphasizing a fixed set of congeners have led to more streamlined data sets that are meant to expedite hazard characterization and risk assessment for the most potent congeners--aryl hydrocarbon receptor (AhR) agonists. Unfortunately, this has made it impossible to confirm or deny significant contributions from the more prevalent components of the mixtures. PCBs may be only coincidentally present, rather than causal, in some diseases. Still, attempts to determine associations with incomplete residue data may lead to erroneous conclusions and make accurate risk assessment even more elusive. Responses not mediated through the AhR are presented and emphasize large data gaps. Dissimilar analytical reports emphasize that selection of analytes is not consistent. Collectively, these data confirm that AhR-focused objectives unintentionally created the impression that nonplanar PCBs have little if any potential for hazards to humans and wildlife. Near steady-state exposure of healthy adults are probably of minor consequence except for emerging correlations with non-Hodgkin's lymphoma; however, pulses of exposure to more labile mixtures may contribute to developmental effects without leaving a residue record. More broadly based criteria are suggested and harmonization of data collection and presentation are desirable. A more comprehensive list of PCB congeners is proposed that would provide more adequate data upon which to base associations with adverse outcomes. PMID:9539012

  20. Differential toxicity of three PCB congeners in developing sea urchin embryos and implication of TEQ approach

    SciTech Connect

    Schweitzer, L.; Suffet, I.; Hose, J.; Bay, S.

    1995-12-31

    The relationship between body burden and toxicity of three individual PCB congeners in developing sea urchin embryos was investigated to evaluate the validity of current predictive models of PCB toxicity in an invertebrate system. The uptake and accumulation of radiolabeled PCB congeners from sea water was measured in the sea urchin embryo tissues and the relative toxicity determined. According to the toxic equivalents (TEQ) approach of assessing risk to mammals, congener 77, a nonortho-substituted congener, is predicted to be more toxic than the diortho-substituted congeners 47 and 153. Using a 72 hour embryo development assay, congener 47 was found to be at least four times as toxic as congener 77, with EC50s of 15.7 and > 72.5 mmol/kg, respectively. Congener 153, a hexachlorobiphenyl, was virtually nontoxic even at the highest dose used. Cytologic and cytogenetic anomalies were studied to find a possibly more sensitive endpoint and to suggest a mechanism of toxicity. The cytogenetic analysis revealed that the PCBs inhibited mitosis. At the highest doses, complete mitotic arrest was observed. Congener 77 was found to be at least two times more toxic than congener 153 but not as toxic as congener 47 using mitotic activity as the endpoint. Thus, the two endpoints of toxicity did not change the order in which the congeners are toxic, but established different EC50s. The relative toxicities of these congeners in this study contradict the structure-activity prediction of the mammalian-based TEQ approach.

  1. A modeling approach to compare ΣPCB concentrations between congener-specific analyses

    USGS Publications Warehouse

    Gibson, Polly P.; Mills, Marc A.; Kraus, Johanna M.; Walters, David M.

    2016-01-01

    Changes in analytical methods over time pose problems for assessing long-term trends in environmental contamination by polychlorinated biphenyls (PCBs). Congener-specific analyses vary widely in the number and identity of the 209 distinct PCB chemical configurations (congeners) that are quantified, leading to inconsistencies among summed PCB concentrations (ΣPCB) reported by different studies. Here we present a modeling approach using linear regression to compare ΣPCB concentrations derived from different congener-specific analyses measuring different co-eluting groups. The approach can be used to develop a specific conversion model between any two sets of congener-specific analytical data from similar samples (similar matrix and geographic origin). We demonstrate the method by developing a conversion model for an example data set that includes data from two different analytical methods, a low resolution method quantifying 119 congeners and a high resolution method quantifying all 209 congeners. We used the model to show that the 119-congener set captured most (93%) of the total PCB concentration (i.e., Σ209PCB) in sediment and biological samples. ΣPCB concentrations estimated using the model closely matched measured values (mean relative percent difference = 9.6). General applications of the modeling approach include (a) generating comparable ΣPCB concentrations for samples that were analyzed for different congener sets; and (b) estimating the proportional contribution of different congener sets to ΣPCB. This approach may be especially valuable for enabling comparison of long-term remediation monitoring results even as analytical methods change over time. 

  2. Detailed PCB congener characterization of influent and effluent at New York and New Jersey WPCPs

    SciTech Connect

    Durell, G.S.; Lizotte, R.D. Jr.; Solomon, M.H.; Green, J.W.; Spadone, J.; Pires, L.

    1995-12-31

    The waste streams at 26 New York City and New Jersey water pollution control plants (WPCP) were characterized for PCB. Time-integrated influent and effluent samples were collected during normal and high (storm) flow conditions; high flow influent simulated what may by-pass the plant and be discharged through combined sewer overflows. State-of-the-art congener-specific analytical methods were used to achieve detection limits from 0.05 to 0.3 ng/L. Concentrations of 71 individual PCB congeners that constitute approximately 95% of the total PCB in Aroclors and environmental samples were determined. The PCB concentrations and congener distributions varied notably among plants. Individual congener concentrations were typically well below 1 ng/L in the effluent, with a few congeners being detected at 5 to 10 ng/L levels in some samples. The concentrations were under 1 ng/L in most influent samples, with occasional determinations above 10 ng/L. The average total PCB concentration, defined as the sum of the 71 individual congener concentrations, at the 26 WPCPs were 27, 110, and 160 ng/L for normal flow effluent, normal flow influent, and high flow influent, respectively. The results indicate that PCB levels in New York City and New Jersey WPCP discharges are generally low, with most effluent having total PCB concentrations below 0.05 {micro}g/L. The PCB levels in the influent were commonly under 0.1 {micro}g/L and became slightly elevated at most plants during storms while at some plants the increase in flow appeared to dilute the PCB in the influent. The WPCPs remove, on average, approximately 75% of the PCB received in the influent.

  3. Investigations into the effects of PCB congeners on reproduction in lake trout from the Great Lakes

    USGS Publications Warehouse

    Mac, Michael J.; Schwartz, T.R.

    1992-01-01

    Eggs of feral lake trout collected in Lake Michigan were reared under laboratory conditions and monitored for egg hatchability, physical abnormalities, and survival of fry. Subsamples of eggs were also analyzed for PCB congeners. A negative correlation was found between egg hatchability and total PCBs but expressing PCB dose as dioxin equivalents did not produce as strong a correlation. No other measure of reproductive success correlated significantly with PCB concentration in the egg.

  4. Development of toxic equivalency factors for PCB congeners and the assessment of TCDD and PCB mixtures in rainbow trout

    SciTech Connect

    Newsted, J.L.; Giesy, J.P.; Crawford, R.A.; Jones, P.D.; Ankley, G.T.; Tillitt, D.E.; Gooch, J.W.; Denison, M.S.

    1995-05-01

    This study was undertaken to evaluate the relationship between mammalian and piscine 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxic equivalency factors (TEFs) for PCBs, based on induction of CYP1A enzyme activity, catalytic protein, and mRNA. Rainbow trout administered a single i.p. injection of TCDD had an average ({+-}SD) ED50 of 0.91 {+-} 0.14 {mu}g TCDD/kg for induction of ethoxyresorufin O-deethylase (EROD) activity. Ortho-substituted PCB congeners 2,3,3{prime},4,4{prime}-pentachlorobiphenyl (PCB 105), 2,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB 118), 2,3,3{prime},4,4{prime},5-hexachlorobiphenyl (PCB 156), and 2,2{prime}3,4,4{prime},5-hexachlorobiphenyl (PCB 138) did not induce CYP1A activity in rainbow trout. Only three non-ortho-substituted PCBs, i.e., 3,3{prime},4,4{prime}-tetrachlorobiphenyl (PCB 77), 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB 126), and 3,3{prime},4,4{prime},5,5{prime}-hexachlorobiphenyl (PCB 169) induced CYP1A enzyme activity, protein, and mRNA. The ED50s for induction of EROD activity were calculated as 134, 5.82, and 93.7 {mu}g/kg for PCB 77, PCB 126, and PCB 169, respectively. The TCDD-TEFs based on EROD activity were 0.0006, 0.0014, and 0.0003 for PCB 77, PCB 126, and PCB 169, respectively. Binary mixtures of TCDD and three PCBs were also evaluated. Based on EROD activity and CYP1A protein, mixtures of TCDD and PCB 77 were slightly greater than additive. Mixtures of TCDD-PCB 156 and TCDD-PCB 126 were slightly less than additive. Results from these studies indicate that mammal-derived TEFs will underestimate the potency of planar chlorinated hydrocarbon mixtures to induce the CYP1A catalytic activity in rainbow trout. Also, while interactions among PCB congeners and TCDD were somewhat equivocal, they did not greatly differ from predicted additive responses.

  5. Developmental exposure to purity-controlled polychlorinated biphenyl congeners (PCB74 and PCB95) in rats: effects on brainstem auditory evoked potentials and catalepsy.

    PubMed

    Lilienthal, Hellmuth; Korkalainen, Merja; Andersson, Patrik L; Viluksela, Matti

    2015-01-01

    Whereas the effects of dioxin-like polychlorinated biphenyls (DL-PCBs) are well described, less is known about non-dioxin-like PCBs (NDL-PCBs), including influences on the nervous system and related behavioral effects after developmental exposure. Following the examination of the highly purified NDL congeners PCB52 and PCB180, we report here the results of experiments with PCB74 and PCB95. Rat dams were orally exposed to equimolar doses of either congener (40μmol/kg bw - 11.68mg PCB74/kg bw or 13.06mg PCB95/kg bw) from gestational day (GD) 10 to postnatal day (PND) 7. Control dams were given the vehicle. Adult offspring were tested for cataleptic behavior after induction with haloperidol, a classical neuroleptic drug, and brainstem auditory evoked potentials (BAEPs), using clicks and tone pips of different frequencies for stimulation. Results revealed slight effects on latencies to movement onset in female offspring exposed to PCB74, whereas PCB74 males and offspring exposed to PCB95 were not affected. Pronounced changes were observed in BAEPs at low frequencies in PCB74 offspring, with elevated thresholds in both sexes. PCB95 increased thresholds in males, but not females. Small effects were detected on latency of the late wave IV in both sexes after developmental exposure to PCB74 or PCB95. Compared with the other NDL-PCB congeners tested, PCB74 caused the most pronounced effects on BAEPs. PMID:25449634

  6. PCB patterns in herring and pike with special regard to co-planar congeners

    SciTech Connect

    Alsberg, T.; Wit, C. de; Eriksson, U.; Jaernberg, U.; Bignert, A.; Olsson, M.

    1995-12-31

    This study investigates the patterns of PCB in two aquatic organisms, herring and pike. The aim is to establish a basis for a model for estimating the levels of co-planar PCBs from the concentrations of nonplanar congeners. The chosen fish populations reflect differences in species, age, habitat (locations) and time of catch, as well as differences in total PCB concentrations. More stable patterns would be presumed, the more homogeneous the population. Herring were sampled at two locations, one in the Bothnian Bay (Harufjaerden) and one in the Southern Baltic (Utlaengan). Two age classes were sampled at each location, 2- and 6-year olds, respectively at Utlaengan, and 2- and 5-year olds, respectively at Harufjaerden. Pike were sampled from Lake Bolmen in southern Sweden in 1992, and pike from the same location but sampled in 1971 were taken from the specimen bank. Ten individuals per population were analyzed. Thirteen PCB congeners were determined, namely PCBs 28, 52, 77, 101, 105, 118, 126, 1 38, 153, 156, 157, 169, 180, thus including the seven PCBs that are measured in the national monitoring program, in addition to three monoortho and three non-ortho PCBs. Regarding the possibility of creating a model for calculating the concentrations of the planar PCBs from those of the non-planar, the results look promising for PCB-126 and PCB-169, whereas PCB-77 shows a lower correlation to the non-planar congeners.

  7. KEY COMPARISON: CCQM-K25: Determination of PCB congeners in sediment

    NASA Astrophysics Data System (ADS)

    Schantz, Michele; Wise, Stephen

    2004-01-01

    Polychlorinated biphenyls (PCBs) consist of 209 possible congeners depending on the substitution of the chlorine atoms around the biphenyl molecule. PCBs have been widely used as industrial fluids, flame retardants, diluents, hydraulic fluids, and dielectric fluids for capacitors and transformers. As a class of compounds, they are environmentally stable and tend to bioaccumulate. Of the 209 possible congeners, approximately 150 congeners have been reported in the environment. Congener-specific PCB methods, which are typically based on gas chromatography (GC) with electron capture detection (ECD) or mass spectrometric (MS) detection, are designed to measure selected priority congeners, but the congeners of interest change with the study and sponsoring agency. A pilot study (CCQM-P17) for the determination of PCB congeners in sediment was organized by NIST and NRC-Canada in 2000. Ten laboratories participated in the pilot study. After discussion and critical review of the data, there was agreement that the pilot study should be followed by a Key Comparison and that the Key Comparison Reference Value (KCRV) should be derived from isotope dilution GC/MS (ID-GC/MS) based methods that had been validated in the Pilot Study. The CCQM-K25 Key Comparison study utilized a sediment sample prepared by mixing known quantities of two sediment materials to simulate a moderately contaminated sample with respect to PCBs. Nine laboratories participated in CCQM-K25 and demonstrated a high level of equivalence in capabilities for determining five PCB congeners (congener numbers 28, 101, 105, 153, and 170) in a moderately contaminated sediment using GC/MS-based methods. The amount of substance concentration for the congeners measured ranged from ~10 ng/g to ~35 ng/g. The relative expanded uncertainties of the KCRVs ranged from 2% to 5%, indicating excellent agreement among the participants that used ID-GC/MS. Results from the one laboratory that used GC/MS with a non-labeled PCB

  8. Polychlorinated biphenyl (PCB) congener concentrations in seabirds found dead in mortality incidents around the British coast.

    PubMed

    Malcolm, H M; Osborn, D; Wright, J; Wienburg, C L; Sparks, T H

    2003-07-01

    Livers from 121 birds killed in mortality incidents in U.K. coastal waters between 1991 and 1996 were analyzed for 16 PCB congeners (IUPAC numbers 8, 18, 28, 31, 52, 77, 101, 118, 126, 128, 138, 149, 153, 169, 170, and 180). Species analyzed were guillemot (Uria aalge), shag (Phalacrocorax arisotelis), kittiwake (Rissa tridactyla), puffin (Fratercula arctica), razorbill (Alca torda), fulmar (Fulmarus glacialis), gannet (Sula bassana), and herring gull (Larus argentatus). This is the first report of PCBs in U.K. seabird tissues to be presented since 1983. Mean concentrations of total PCBs ranged from 0.47 to 15.8 mg/kg WW, similar to concentrations reported for North Sea birds during the 1970s and 1980s and lower than those reported for the same species in the Irish Sea during the late 1960s and early 1970s. The congeners generally present in the highest concentrations were (in decreasing order) 153, 138, 180, 118, and 170. Despite the birds having similar diets, both inter- and intraspecies differences in PCB congener profile were found. In guillemots from several sites on the east coast, the dominant congener was 138, compared to guillemots from the south coast, which had the more typical congener pattern found in seabirds. Some of the differences in total PCB values could be due to different causes of death, with a subsequent effect on body lipid levels. PMID:12948183

  9. Bioaccumulation of PCB congeners by blue mussels (Mytilus edulis) deployed in New Bedford Harbor, Massachusetts

    SciTech Connect

    Bergen, B.J. . Environmental Research Lab., Science Applications International Corp.); Nelson, W.G.; Pruell, R.J. . Environmental Research Lab.)

    1993-09-01

    Blue mussels (Mytilus edulis) were deployed to monitor the levels of bioavailable contaminants during a pilot dredging project in New Bedford Harbor (NBH), Massachusetts. Dissolved and particulate seawater samples also were collected periodically during these deployments. Polychlorinated biphenyl (PCB) congener concentrations in both mussel tissue and seawater samples were among the quantified contaminants. Large differences in the dissolved and particulate PCB concentrations in seawater and tissue residue concentrations in mussels were observed along a gradient from the upper harbor to Buzzards Bay. Bioconcentration factors (BCFs) were calculated for six PCB congenors at two stations in NBH and a reference site in Buzzards Bay. Equations were generated relating the log BCF to the log octanol/water partition coefficient (K[sub ow]) for these congeners. A consistent relationship was found between dissolved PCB congener concentrations and tissue concentrations in the mussels. This study demonstrates the utility of the blue mussel as a monitoring organism for quantifying bioavailable contaminants in seawater and for relating PCB tissue residues with seawater concentrations.

  10. Enhanced accumulation of PCB congeners by Baltic Sea blue mussels, Mytilus edulis, with increased algae enrichment

    SciTech Connect

    Gilek, M.; Bjoerk, M.; Broman, D.; Kautsky, N.; Naef, C.

    1996-09-01

    The objective of this study was to examine if natural variations in the quantity of phytoplankton-derived particulate and dissolved organic carbon influences the accumulation of polychlorinated biphenyls (PCBs) in the tissues of Baltic Sea blue mussels (Mytilus edulis L.). In a laboratory flow-through experiment the authors exposed M. edulis to the technical PCB mixture Aroclor{reg_sign} 1248 for 21 d at three different enrichments of the unicellular green algae Chlamydomonas sp., 0.10, 0.16, and 0.32 mg particulate organic carbon (POC)/L. Tissue and water concentrations were determined for seven PCB congeners and 21-d bioaccumulation factors were calculated against total water concentrations. Contrary to what would be expected, an increase in algae enrichment from 0.10 to 0.32 mg POC/L resulted in an enhanced PCB accumulation by a factor of approx. 2. This increase in PCB accumulation was more pronounced for PCB congeners with lower hydrophobicity. These observations have implications for the design of laboratory accumulation studies and potentially for PCB accumulation and cycling in field populations of suspension-feeding mussels in response to changes in eutrophication status.

  11. Disposition of toxic PCB congeners in snapping turtle eggs: expressed as toxic equivalents of TCDD

    SciTech Connect

    Bryan, A.M.; Stone, W.B.; Olafsson, P.G.

    1987-11-01

    Studies of snapping turtles, taken from the region of the Upper Hudson River, in New York State, revealed exceedingly high levels of PCBs in the adipose tissue. There is evidence to suggest that large reserves of fat provide protection against chlorinated hydrocarbon toxicity. Such storage may protect snapping turtle eggs from disposition of toxic PCB congeners and account for the apparent absence of reports regarding detrimental effects on the hatchability of eggs from turtles living in the vicinity of the upper Hudson River. The present study was undertaken to determine if indeed these eggs are protected against disposition of toxic PCB congeners by the presence of large reserves of fat. Although tissue volumes play an important role in determining the initial site of disposition, the major factor controlling the elimination of these compounds involves metabolism. For simple halogenated benzenes as well as for more complex halogenated biphenyls, oxidative metabolism catalyzed by P-448, occurs primarily at the site of two adjacent unsubstituted carbon atoms via arene oxide formation leading to the formation of water soluble metabolites. Toxicological studies have demonstrated that the most toxic PCB congeners, isosteriomers of tetrachlorodibenzo-p-dioxin (TCDD), require no metabolic activation. These compounds have chlorine atoms in the meta and para positions of both rings. It may be concluded that the structures of PCB congeners and isomers which favor induction of cytochrome P-448 are also those which are toxic and resist metabolism. It is the objective of the present study to determine if the heavy fat bodies of the female turtle provide a sufficiently large sink to retain the toxic congeners and prevent their incorporation into the eggs.

  12. Accumulation of PCB congeners in nestling tree swallows (Tachycineta bicolor) on the Hudson River, New York

    USGS Publications Warehouse

    Echols, K.R.; Tillitt, D.E.; Nichols, J.W.; Secord, A.L.; McCarty, J.P.

    2004-01-01

    Tree swallows (Tachycineta bicolor) were used as a sentinel species to monitor the contamination and bioavailability of polychlorinated biphenyls (PCBs) in the Hudson River watershed. Several tree swallow nest box colonies around and downstream from Hudson Falls, NY, were studied. Tree swallow eggs, adults, and 5-, 10-, and 15-day-old nestlings were collected and analyzed for 103 PCB congeners. Emergent insects collected by net (primarily Odonata) or as a food bolus (primarily Diptera) taken from the mouths of adult tree swallows returning to the nest were analyzed in the same manner. Total PCB concentrations (wet weight) in eggs from two contaminated sites ranged from 9000 to 25 000 ng/g and accumulated to 32 000 and 96 000 ng/g in 15-day-old nestling at two contaminated sites. The congener patterns of PCBs in eggs, nestlings, and adults were compared to those found in emergent insects (Odonata and Diptera) using principal components analysis. The PCB patterns of the biota differed from that of Aroclor technical mixtures. PCB patterns in adult tree swallows were similar to those in eggs, while the patterns in dietary insects were similar to nestling tree swallows. Uptake rate constants were determined for tree swallow nestlings and compared between the two contaminated sites. The estimated PCB congener uptake rate constants were 0.008-0.02 d-1 based on uptake in nestlings until day 15 post-hatch. The rate constants were comparable between the two study areas and may be used to predict nestling contamination at other locations. Our studies confirm the utility of nestling tree swallows to evaluate localized PCB contamination.

  13. Coating effects on the glass adsorption of polychlorinated biphenyl (PCB) congeners.

    PubMed

    Lung, S C; Altshul, L M; Ford, T E; Spengler, J D

    2000-12-01

    The effects of coating materials on polychlorinated biphenyl (PCB) adsorption in aqueous solution were assessed in an attempt to minimize PCB sorption loss during sampling processes. A coating material, which enhances PCB adsorption and allows adsorbed PCBs to be readily extracted by solvents, can act as a sampling concentrator to reduce PCB losses from both adsorption and evaporation. Several coating materials were evaluated, including paraffin oil, silicone oil, dimethyldichlorosilane (Sylon-CT), Prosil 28 and polydimethylsiloxane (PDS) with viscosity 0.65, 50 (PDS 50), and 500 (PDS 500) cSt. PDS and silicone oil enhanced adsorption for all five congeners examined (IUPAC No. 28, 52, 101, 138, and 180). Sylon-CT, paraffin oil and Prosil 28 had inconsistent effects on adsorption of different congeners. Desorption of adsorbed PCBs onto all coating types was assessed. The recovery efficiency of extracting PCBs with solvents was enhanced greatly with all coatings as opposed to non-coated surfaces, with the exception of paraffin oil. Coating with silicon oil, PDS 50, and 500 resulted in virtually 100% recovery of adsorbed PCBs. It was also found that Teflon containers were poor substitutes for glass containers and failed to minimize PCB losses. Among the materials studied, the best coating that could be used as a sampling concentrator was PDS 500. PMID:11061308

  14. Coculture degradation of selected PCB congeners by two Acinetobacter sp

    SciTech Connect

    Adriaens, P.

    1989-01-01

    Polychlorinated biphenyls (PCBs) have been introduced in the environment for nearly six decades and are considered to be refractile to microbial attack, since PCBs have to be degraded via cometabolic processes, which occur in the obligate presence of an alternative growth substrate. However, cometabolism of PCBs has been demonstrated to accumulate chlorobenzoates as the main intermediates. Therefore, the complete mineralization of PCBs can only be obtained by coculturing at least a PCB cometabolizing and a chlorobenzoate utilizing microorganism, or by constructing a recombinant strain harboring the complementary pathways of both strains. Therefore, coculture mineralization of PCBs in suspended culture was obtained by providing biphenyl or 4-chlorobiphenyl as the growth substrate for Acinetobacter sp. strain P6, a PCB cometabolizer, while the chlorobenzoates were used as growth substrates by Acinetobacter sp. strain 4-CB1, which was isolated on 4-chlorobenzoate. 4-Chlorobenzoate (4-CB) was metabolized after hydrolytic dehalogenation to 4-hydroxybenzoate (4-HB) via the protocatechuate pathway. Acinetobacter sp. strain 4-CB1 has the metabolic ability to carry out the degradation of 3,4-DCB. Although this strain does not grow on this compound, it cometabolizes 3,4-DCB to 3-chloro-4-hydroxybenzoate (3-C-4-OHB), which is used as a growth substrate and further metabolized via 4-carboxy-1,2-benzoquinone. This degradation process was termed cryptic cometabolism. 3,4-DCB has shown to be a substrate inhibitor (Ki = 1,840 {mu}M) and an uncompetitive inhibitor for 4-CB metabolism. Additionally, 3-C-4-OHB was a competitive inhibitor (Ki = 12 {mu}M) for the 4-HB monooxygenase, while the quinone uncompetitively inhibited 4-CB metabolism (Ki = 50 {mu}M).

  15. Acute toxicity of PCB congeners to Daphnia magma and Pimephales promelas

    SciTech Connect

    Dillon, T.M. ); Burton, W.D.S. )

    1991-02-01

    The acute toxicity (EC50/LC50) of commercial PCB mixtures has been reported to range from 2.0 to 283 ug/L. Because PCBs are very hydrophobic most biological studies have utilized a carrier solvent to facilitate introduction of PCBs into aqueous solution. As a result, biological effects are often reported at exposure concentrations exceeding water solubility. The purpose of this work was to evaluate the comparative toxicity of selected PCB congeners without carrier solvents. These tests were conducted on early life stages of two sensitive freshwater organisms, Daphnia magna and Pimephales promelas.

  16. Polychlorinated biphenyl (PCB) congener effects on the longevity of the housefly

    SciTech Connect

    Tehseen, W.M.; Hansen, L.G.; Schaeffer, D.J. )

    1992-01-01

    The microsomal monooxygenase system in the housefly is well-characterized, active, inducible and inhibited by the same types of compounds as in vertebrate systems. Flies metabolize PCBs to polar products and retain congeners from a commercial mixture in proportions consistent with PCB biotransformation and elimination in vertebrates. Although TCDD has been shown to have a high affinity for, and be an effective agonist of the juvenile hormone receptor in insects, toxic manifestations in adult insects may differ from those in certain highly sensitive vertebrate species. This study was undertaken to determine if the housefly bioassay could effectively compare the net adverse biological activity of a group of PCB congeners independent of Ah receptor effects.

  17. The Effects of Individual PCB Congeners on the Soil Bacterial Community Structure and the Abundance of Biphenyl Dioxygenase Genes

    PubMed Central

    Correa, Paola A.; Lin, LianShin; Just, Craig L.; Hu, Dingfei; Hornbuckle, Keri C.; Schnoor, Jerald L.; Van Aken, Benoit

    2009-01-01

    Polychlorinated biphenyls (PCBs) are toxic environmental contaminants that represent a class of 209 congeners characterized by different degree of chlorination and substitution patterns. Most of experimental studies about microbial degradation of PCBs have been conducted on PCB mixtures, even though evidence accumulated in bacteria and other organisms shows that exposure to different congeners may have different biological effects. Microcosm experiments were conducted using aerobic agitated soil slurries individually exposed to PCB congeners with different degrees of chlorination: PCB-3, 15, 28, and 77, and the commercial mixture Aroclor 1242. After four weeks of incubation, PCBs were analyzed by gas chromatography/mass spectrometry (GC/MS) showing different transformation extents: With the exception of PCB-15 that was not significantly transformed (7%), biodegradation rates decreased with the degree of chlorination, from 75% for PCB-3 to 22% for PCB-77 and Aroclor 1242. The bacterial abundance, as measured by colony counting and 16S rDNA quantification by real-time PCR, was lower (of about 40%) in soil microcosms exposed to the higher-chlorinated congeners, PCB-28, PCB-77, and Aroclor 1242, as compared to non-exposed soils and soils exposed to the lower-chlorinated congeners, PCB-3 and PCB-15. The relative abundance of different taxonomic groups, as determined by real-time PCR, revealed an increase of β-Proteobacteria and Actinobacteria in all microcosms exposed to PCBs, as compared with non-exposed soil. In addition, exposure to PCB-77 and Aroclor 1242 resulted in a higher abundance of α-Proteobacteria and Acidobacteria. Globally, these results suggest that exposure to PCBs (and especially to higher-chlorinated congeners and Aroclor 1242) selected bacterial groups involving most known PCB degraders, i.e., β-Proteobacteria and Acidobacteria. The quantification of biphenyl dioxygenase (BPH) genes - involved in the aerobic degradation of PCBs - using real

  18. Distinguishing PCB Isomeric Congeners with their Gas Chromatographic and Mass Spectrometric Ortho Effect using Comprehensive Gas Chromatography

    EPA Science Inventory

    The 209 polychlorinated biphenyl (PCB) congeners and associated nine isomeric groups (nine groups of PCBs with the same degree of chlorination) have been long recorded as high endocrine disrupting chemicals in the environment. Difficult analytical problems exist, in those frequen...

  19. Temporal and spatial trends in total PCB and PCB congeners in biota in a river-reservoir system

    SciTech Connect

    Horwitz, R.J.; McNair, J.N.; Hermanson, M.H.

    1995-12-31

    Since 1984, biennial studies of PCBs have been conducted in fishes, crayfish and insects in the Housatonic River, CT., and additional data are available from earlier studies. PCB data quantitated from presumptive Aroclor concentrations overestimated total PCB concentrations ([TPCB]) by about 13%, although the estimates by the 2 methods were very highly correlated. Ages of all fish specimens were determined. Spatial and temporal trends in [TPCB] were analyzed using ANCOVA to adjust for relationships between [TPCB] and age, lipid content, location and sex. Adjusted [TPCB] consistently decreased in the downstream direction. [TPCB] decreased within the years after cessation of direct inputs (around 1978). However, in the 1984--1992 period [TPCB] trends were weak and variable. Concentrations in 1994 were lower than previous years (statistical comparisons showing 1994 to be the lowest year or among a group of years with the lowest concentrations). Between year differences were probably related to temperature, storm flows and other factors affecting availability and accumulation. These variations were greater in riverine sites than in reservoirs. In brown trout, [TPCB] increased rapidly within 1--2 months after stocking. Over longer periods, [TPCB] were more closely related to seasonal cycles in lipid content rather than to time in river. Increases in [TPCB] with age were most evident for long-lived species in reservoirs. Several congeners which are abundant in Aroclors 1254 and 1260 predominated the samples. However, spatial and temporal differences in accumulation of different congeners were evident. Spatial differences in the concentration of some marker congeners reflected enrichment of these congeners from original Aroclor 1254 and 1260 sources, as well as supplemental inputs of Aroclor 1242.

  20. Foodchain bioaccumulation patterns of pesticides, PCB isomers and dioxin/furan congeners in the Great Lakes

    SciTech Connect

    Whittle, D.M.; Kiriluk, R.M.; Carswell, A.; Keir, M.J.

    1994-12-31

    Lake Ontario is one of the most contaminated Great Lakes. A detailed analysis of whole body concentrations of organic contaminants was conducted on a simple 4 compartment coldwater foodchain consisting of 7 species including several invertebrate diet items, prey fish species and the top predator lake trout. Sediment samples from the same site were analyzed for a similar suite of contaminants. Analyses were performed using a combination of HRMS/MS and GC/MS. All concentrations were reported on a whole animal wet weight basis and lipid weight concentrations. Total Toxic Equivalent Factors (TEFS) were calculated for both dioxin and furan isomers and coplanar PCBs. PCB 110 (pentachlorobiphenyl) was the dominant congener in sediment samples as well as samples of benthic invertebrates. On the other hand, PCB 138 and 153 (hexachlorobiphenyls) were found at the highest concentration in the top predator lake trout and a prey species that feeds primarily in the water column. Mysis relicta, a zooplankton species that migrates diurnally through the water column, had similar levels of both PCB 110 and PCB 138/153. PCB 77 was consistently the highest coplanar PCB found in all samples. In all biological samples analyzed 2,3,7,8 substituted tetrachlorodioxin and furan isomers were consistently found at the highest levels. Lipid normalization of all whole body data did not significantly change the bioaccumulation factors calculated using wet weight concentrations.

  1. Toxicological consequences of feeding PCB congeners to infant rhesus (Macaca mulatta) and cynomolgus (Macaca fascicularis) monkeys.

    PubMed

    Arnold, D L; Bryce, F; Mes, J; Tryphonas, H; Hayward, S; Malcolm, S

    1999-01-01

    In a study designed to minimize interspecies extrapolation of toxicological data, nine rhesus (Macaca mulatta) and 15 cynomolgus (M. fascicularis) day-old infant monkeys were separated from their dams following parturition and hand-reared using a liquid non-human primate formulation. The infants were randomly divided into a control and a treated group which received a mixture of polychlorinated biphenyl (PCB) congeners analogous to those found in breast milk from Canadian women. The concentration of congeners in the dosing media resulted in each infant receiving a total of 7.5 microg PCB congeners/kg body weight/day. The congeners were added either to the liquid formulation or to corn oil and administered to the back of the monkey's mouth for 20 weeks. Monthly blood and adipose specimens were obtained during the dosing period and then periodically until the monkey was necropsied or taken off test (minimum of 66 weeks on test) for congener analysis. Parameters such as body weight, formula consumption, tooth eruption, somatic measurements, haematology and serum biochemistry were monitored throughout the study. In addition, a qualitative evaluation of the absorption and depletion of the various congeners was undertaken as was an immunological evaluation. For the monitored parameters, very few differences were found to be statistically significant. For the immunological parameters, the only statistically differences found were a reduction over time for immunoglobulins M and G antibodies to sheep red blood cells (cyno, P = 0.025; rhesus, P = 0.002) and a treatment-related reduction in the levels of the HLA-DR cell surface marker (mean percent, P = 0.016; absolute levels, P = 0.027). There were some qualitative differences regarding absorption and depletion rates for the various congeners, but it could not be definitely ascertained whether these differences were due to species differences or dosing mode. However, statistically significant differences were found for

  2. A New Player in Environmentally Induced Oxidative Stress: Polychlorinated Biphenyl Congener, 3,3′-Dichlorobiphenyl (PCB11)

    PubMed Central

    Aykin-Burns, Nukhet

    2013-01-01

    Recent analysis of air samples from Chicago and Lake Michigan areas observed a ubiquitous airborne polychlorinated biphenyl (PCB) congener, 3,3′-dichlorobiphenyl (PCB11). Our analysis of serum samples also revealed the existence of hydroxylated metabolites of PCB11 in human blood. Because PCBs and PCB metabolites have been suggested to induce oxidative stress, this study sought to determine whether environmental exposure to PCB11 and its 4-hydroxyl metabolite could induce alterations in steady-state levels of reactive oxygen species (ROS) and cytotoxicity in immortalized human prostate epithelial cells (RWPE-1). This study also examines if antioxidants could protect the cells from PCB11-induced cytotoxicity. Exponentially growing RWPE-1 cells were exposed to PCB11 and its metabolite, 3,3′-dichlorobiphenyl-4-ol (4-OH-PCB11), as well as an airborne PCB mixture resembling the Chicago ambient air congener profile, every day for 5 days. Results showed that 4-OH-PCB11 could significantly induce cell growth suppression and decrease the viability and plating efficiency of RWPE-1 cells. 4-OH-PCB11 also significantly increased steady-state levels of intracellular superoxide, O2 •−, as well as hydroperoxides. Finally, treatment with the combination of polyethylene glycol–conjugated CuZn superoxide dismutase and catalase added 1h after 4-OH-PCB11 exposures, significantly protected RWPE-1 cells from PCB toxicity. The results strongly support the hypothesis that exposure to a hydroxylated metabolite of PCB11 can inhibit cell proliferation and cause cytotoxicity by increasing steady-state levels of ROS. Furthermore, antioxidant treatments following PCBs exposure could significantly mitigate the PCB-induced cytotoxicity in exponentially growing human prostate epithelial cells. PMID:23997111

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

    PubMed

    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

  4. Comparison of nonplanar and coplanar PCB congener partitioning in seawater and bioaccumulation in blue mussels (Mytilus edulis)

    SciTech Connect

    Bergen, B.J.; Nelson, W.G.; Pruell, R.J.

    1996-09-01

    The partitioning of 18 nonplanar and three coplanar polychlorinated biphenyl (PCB) congeners was quantified in New Bedford Harbor, Massachusetts. Concurrently, bioaccumulation of these congeners was measured in blue mussels deployed for 7 and 28 d in New Bedford Harbor, and bioconcentration factors (BCFs) were calculated for each congener. The PCB concentrations measured in the dissolved and particulate fractions of seawater samples were used to calculate partition coefficients (K{sub p}) for each congener. These values were correlated with reported octanol/water partition coefficients (K{sub ow}). No significant differences (p > 0.05) were observed in the relationships between K{sub p} and K{sub ow} for the coplanar congeners relative to the nonplanar congeners. Coplanar congeners reached steady state faster than the nonplanar congeners; however, after 28 d a similar relationship was observed between BCF and K{sub ow} in coplanar and nonplanar congeners. These data indicate that coplanar PCBs partition in seawater and accumulate in mussels similarly to nonplanar PCBs with the same number of chlorines.

  5. GC/MS ANALYSIS OF PCB CONGENERS IN BLOOD OF THE HARBOR SEAL PHOCA VITULINA FROM SAN FRANCISCO BAY

    EPA Science Inventory

    Here we report a validated technique for quantifying up to 20 specific PCB congeners in 1-2 g samples of whole blood with a detection limit below 1 ng/g (ppb) wet weight. Specimens were analyzed from 14 harbor seals sampled in south San Francisco Bay, California during 1991-1992....

  6. HIGH RESOLUTION MODELLING OF PCB CONGENERS IN LAKE MICHIGAN USING THE LAKE MICHIGAN (LM3) CONTAMINANT MODEL

    EPA Science Inventory

    The Lake Michigan Level 3 (LM3) Model is a numerical model of Lake Michigan used to predict the fate and transport of 54 PCB congeners. The LM3 model segments Lake Michigan horizontally with a 5 x 5 km grid and vertically with 19 sigma layers for a total of 44,042 water column se...

  7. Response to Ecological Risk Assessment Forum Request for Information on the Benefits of PCB Congener-Specific Analyses

    EPA Science Inventory

    In August, 2001, the Ecological Risk Assessment Forum (ERAF) submitted a formal question to the Ecological Risk Assessment Support Center (ERASC) on the benefits of evaluating PCB congeners in environmental samples. This question was developed by ERAF members Bruce Duncan and Cla...

  8. Estimation of uptake rate constants for PCB congeners accumulated by semipermeable membrane devices and brown treat (Salmo trutta)

    USGS Publications Warehouse

    Meadows, J.C.; Echols, K.R.; Huckins, J.N.; Borsuk, F.A.; Carline, R.F.; Tillitt, D.E.

    1998-01-01

    The triolein-filled semipermeable membrane device (SPMD) is a simple and effective method of assessing the presence of waterborne hydrophobic chemicals. Uptake rate constants for individual chemicals are needed to accurately relate the amounts of chemicals accumulated by the SPMD to dissolved water concentrations. Brown trout and SPMDs were exposed to PCB- contaminated groundwater in a spring for 28 days to calculate and compare uptake rates of specific PCB congeners by the two matrixes. Total PCB congener concentrations in water samples from the spring were assessed and corrected for estimated total organic carbon (TOC) sorption to estimate total dissolved concentrations. Whole and dissolved concentrations averaged 4.9 and 3.7 ??g/L, respectively, during the exposure. Total concentrations of PCBs in fish rose from 0.06 to 118.3 ??g/g during the 28-day exposure, while concentrations in the SPMD rose from 0.03 to 203.4 ??g/ g. Uptake rate constants (k1) estimated for SPMDs and brown trout were very similar, with k1 values for SPMDs ranging from one to two times those of the fish. The pattern of congener uptake by the fish and SPMDs was also similar. The rates of uptake generally increased or decreased with increasing K(ow), depending on the assumption of presence or absence of TOC.The triolein-filled semipermeable membrane device (SPMD) is a simple and effective method of assessing the presence of waterborne hydrophobic chemicals. Uptake rate constants for individual chemicals are needed to accurately relate the amounts of chemicals accumulated by the SPMB to dissolved water concentrations. Brown trout and SPMDs were exposed to PCB-contaminated groundwater in a spring for 28 days to calculate and compare uptake rates of specific PCB congeners by the two matrixes. Total PCB congener concentrations in water samples from the spring were assessed and corrected for estimated total organic carbon (TOC) sorption to estimate total dissolved concentrations. Whole and

  9. Laboratory estimation of net trophic transfer efficiencies of PCB congeners to lake trout (Salvelinus namaycush) from its prey

    USGS Publications Warehouse

    Madenjian, Charles P.; Rediske, Richard R.; O'Keefe, James P.; David, Solomon R.

    2014-01-01

    A technique for laboratory estimation of net trophic transfer efficiency (γ) of polychlorinated biphenyl (PCB) congeners to piscivorous fish from their prey is described herein. During a 135-day laboratory experiment, we fed bloater (Coregonus hoyi) that had been caught in Lake Michigan to lake trout (Salvelinus namaycush) kept in eight laboratory tanks. Bloater is a natural prey for lake trout. In four of the tanks, a relatively high flow rate was used to ensure relatively high activity by the lake trout, whereas a low flow rate was used in the other four tanks, allowing for low lake trout activity. On a tank-by-tank basis, the amount of food eaten by the lake trout on each day of the experiment was recorded. Each lake trout was weighed at the start and end of the experiment. Four to nine lake trout from each of the eight tanks were sacrificed at the start of the experiment, and all 10 lake trout remaining in each of the tanks were euthanized at the end of the experiment. We determined concentrations of 75 PCB congeners in the lake trout at the start of the experiment, in the lake trout at the end of the experiment, and in bloaters fed to the lake trout during the experiment. Based on these measurements, γ was calculated for each of 75 PCB congeners in each of the eight tanks. Mean γ was calculated for each of the 75 PCB congeners for both active and inactive lake trout. Because the experiment was replicated in eight tanks, the standard error about mean γ could be estimated. Results from this type of experiment are useful in risk assessment models to predict future risk to humans and wildlife eating contaminated fish under various scenarios of environmental contamination.

  10. The effects of an environmentally relevant 58-congener polychlorinated biphenyl (PCB) mixture on cardiac development in the chick embryo.

    PubMed

    Carro, Tiffany; Taneyhill, Lisa A; Ann Ottinger, Mary

    2013-06-01

    Chicken (Gallus domesticus) embryonic exposure in ovo to a 58-congener polychlorinated biphenyl (PCB) mixture resulted in teratogenic heart defects in chick embryos at critical heart developmental stages Hamburger-Hamilton (HH) stages 10, 16, and 20. The 58-congener mixture contained relative proportions of primary congeners measured in belted sandpiper (Megaceryle alcyon) and spotted sandpiper (Actitis macularia) eggs collected along the upper Hudson River, New York, USA, and chicken doses were well below observed environmental exposure levels. Embryos were injected with 0.08 µg PCBs/g egg weight and 0.50 µg PCBs/g egg weight (0.01 and 0.064 ng toxic equivalent/g, respectively) at embryonic day 0, prior to incubation. Mortality of exposed embryos was increased at all developmental stages, with a marked rise in cardiomyopathies at HH16 and HH20 (p < 0.05). Heart abnormalities occurred across all treatments, including abnormal elongation and expansion of the heart tube at HH10, improper looping and orientation, indentations in the emerging ventricular wall (HH16 and HH20), and irregularities in overall heart shape (HH10, HH16, and HH20). Histology was conducted on 2 cardiac proteins critical to embryonic heart development, ventricular myosin heavy chain and titin, to investigate potential mechanistic effects of PCBs on heart development, but no difference was observed in spatiotemporal expression. Similarly, cellular apoptosis in the developing heart was not affected by exposure to the PCB mixture. Conversely, cardiomyocyte proliferation rates dramatically declined (p < 0.01) at HH16 and HH20 as PCB exposure concentrations increased. Early embryonic cardiomyocyte proliferation contributes to proper formation of the morphology and overall thickness of the ventricular wall. Therefore, in ovo exposure to this 58-congener PCB mixture at critical stages adversely affects embryonic heart development. PMID:23417652

  11. Laboratory Estimation of Net Trophic Transfer Efficiencies of PCB Congeners to Lake Trout (Salvelinus namaycush) from Its Prey

    PubMed Central

    Madenjian, Charles P.; Rediske, Richard R.; O'Keefe, James P.; David, Solomon R.

    2014-01-01

    A technique for laboratory estimation of net trophic transfer efficiency (γ) of polychlorinated biphenyl (PCB) congeners to piscivorous fish from their prey is described herein. During a 135-day laboratory experiment, we fed bloater (Coregonus hoyi) that had been caught in Lake Michigan to lake trout (Salvelinus namaycush) kept in eight laboratory tanks. Bloater is a natural prey for lake trout. In four of the tanks, a relatively high flow rate was used to ensure relatively high activity by the lake trout, whereas a low flow rate was used in the other four tanks, allowing for low lake trout activity. On a tank-by-tank basis, the amount of food eaten by the lake trout on each day of the experiment was recorded. Each lake trout was weighed at the start and end of the experiment. Four to nine lake trout from each of the eight tanks were sacrificed at the start of the experiment, and all 10 lake trout remaining in each of the tanks were euthanized at the end of the experiment. We determined concentrations of 75 PCB congeners in the lake trout at the start of the experiment, in the lake trout at the end of the experiment, and in bloaters fed to the lake trout during the experiment. Based on these measurements, γ was calculated for each of 75 PCB congeners in each of the eight tanks. Mean γ was calculated for each of the 75 PCB congeners for both active and inactive lake trout. Because the experiment was replicated in eight tanks, the standard error about mean γ could be estimated. Results from this type of experiment are useful in risk assessment models to predict future risk to humans and wildlife eating contaminated fish under various scenarios of environmental contamination. PMID:25226430

  12. Cytochrome P450 responses and PCB congeners in pipping heron embryos from Virginia, the Great Lakes and San Francisco Bay

    USGS Publications Warehouse

    Rattner, B.A.; Melancon, M.J.; Custer, T.W.; Tillett, D.E.; Woodin, Bruce R.; Stegeman, John J.

    1992-01-01

    Pipping black-crowned night-heron (Nvcticorax nvcticorax) embryos were collected from undisturbed (Chincoteague National Wildlife Refuge VA; CNWR) and industrialized (Cat Island, Green Bay WI and San Francisco Bay, CA; SFB) locations. Hepatic monooxygenases (AHH, EROD, BROD, ECOD) were induced up to 100-fold, and were correlated (r=0.50 to 0.72) with total PCB burdens (N =61 embryos). A subset of 30 embryos have now been analyzed by GC/MS for 12 AHH-active PCB congeners and by Western blot for cytochromes P450lA and P450llB. At Cat Island, concentrations of 8 congeners were greater (P <0.05) than at CNWR. P450lA and P450llB were detected in 44% and 100% of the Cat Island embryos compared to 8% and 33% of the CNWR + SFB embryos. Cytochrome P450 parameters were correlated with the total PCBs (r =0.44 to 0.67) and with at least 9 PCB congeners (r =0.39 to 0.77). Since P450 responses might be affected by other contaminants, sample extract potency in the H411E rat hepatoma bioassay is being determined to study relationships among dioxin equivalents and cytochrome P450 parameters.

  13. Phenomenological and Spectroscopic Analysis on the Effects of Sediment Ageing and Organic Carbon on the Fate of a PCB Congener Spiked to Sediment

    EPA Science Inventory

    This study assesses the full cycle transport and fate of a polychlorinated biphenyl (PCB) congener spiked to sediment to empirically and spectroscopically investigate the effects of sediment ageing and organic carbon on the adsorption, desorption, and reaction of the PCB. Caesar ...

  14. Exposure to the three structurally different PCB congeners (PCB 118, 153, and 126) results in decreased protein expression and altered steroidogenesis in the human adrenocortical carcinoma cell line H295R.

    PubMed

    Tremoen, Nina Hårdnes; Fowler, Paul A; Ropstad, Erik; Verhaegen, Steven; Krogenæs, Anette

    2014-01-01

    Polychlorinated biphenyls (PCB), synthetic, persistent organic pollutants (POP), are detected ubiquitously, in water, soil, air, and sediments, as well as in animals and humans. PCB are associated with range of adverse health effects, such as interference with the immune system and nervous system, reproductive abnormalities, fetotoxicity, carcinogenicity, and endocrine disruption. Our objective was to determine the effects of three structurally different PCB congeners, PCB118, PCB 126, and PCB 153, each at two concentrations, on the steroidogenic capacity and proteome of human adrenocortical carcinoma cell line cultures (H295R) . After 48 h of exposure, cell viability was monitored and estradiol, testosterone, cortisol and progesterone secretion measured to quantify steroidogenic capacity of the cells. Two-dimensional (2D) gel-based proteomics was used to screen for proteome alterations in H295R cells in response to the PCB. Exposure to PCB 118 increased estradiol and cortisol secretion, while exposure to PCB 153 elevated estradiol secretion. PCB 126 was the most potent congener, increasing estradiol, cortisol, and progesterone secretion in exposed H295R cells. Seventy-three of the 711 spots analyzed showed a significant difference in normalized spot volumes between controls (vehicle only) and at least one exposure group. Fourteen of these protein spots were identified by liquid chromatography with mass spectroscopy (LC-MS/MS). Exposure to three PCB congeners with different chemical structure perturbed steroidogenesis and protein expression in the H295R in vitro model. This study represents an initial analysis of the effects on proteins and hormones in the H295R cell model, and additional studies are required in order to obtain a more complete understanding of the pathways disturbed by PCB congeners in H295R cells. Overall, alterations in protein regulation and steroid hormone synthesis suggest that exposure to PCB disturbs several cellular processes, including

  15. Maternal-to-fetal transfer and concentration profiles of PCB congeners for Steller sea lions (Eumetopias jubatus) from Hokkaido, Japan.

    PubMed

    Kubo, Keiko; Yamaguchi, Katsuyuki; Ishinazaka, Tsuyoshi; Yamada, Wakana; Hattori, Kaoru; Tanaka, Shunitz

    2014-01-15

    The concentrations of PCB congeners in the blubber and liver of mother Steller sea lions (Eumetopias jubatus; SSLs) and their fetuses from the coast of Hokkaido, Japan in 2008, 2010 and 2012 were analyzed by HRGC-HRMS, in order to elucidate PCB congener profiles and maternal-to-fetal transfer of PCBs in SSLs. ΣPCBs in the fetuses were 1400 ± 660 (the mean ± SD) ng/g-fat in the blubber and 570 ± 320 ng/g-fat in the liver, respectively. There was a concern that SSLs had been contaminated by PCBs during the fetal period. The concentrations of the major congeners in the blubber and liver were a correlation between the fetus and mother (blubber: r=0.9934, liver: r=0.9160; P ≦ 0.05). The results indicated that PCBs in the fetuses came from the mothers. #177 and #199 showed no correlations between the fetus and the mother in the blubber and liver. This indicated a selective capture by some natural protector such as the placenta. PMID:24269191

  16. A long-term study of anaerobic dechlorination of PCB congeners by sediment microorganisms pathways and mass balance

    SciTech Connect

    Rhee, G.Y.; Sokol, R.C.; Bush, B. . Wadsworth Center for Labs. and Research); Bethoney, C.M. . School of Public Health, New York State Dept. of Health)

    1993-10-01

    Reductive dechlorination of PCBs by Hudson River sediment microorganisms was investigated using individual congeners, 2,3,4,2[prime],4[prime],5[prime]-, 2,4,5,2[prime],4[prime],5[prime]-, 2,3,4,5,6-, 2,4,2[prime],4[prime]-, and 3,4,3[prime],4[prime]-chlorobiphenyls (CBPs) in long-term studies lasting 15 to 20 months. The dechlorination of 2,3,4,2[prime],4[prime],5[prime]-CBP yielded 2,4,5,2[prime],4[prime]-, 2,4,2[prime],4[prime]-, 2,4,2[prime],5[prime]-, and 2,4,2[prime],5[prime]-, and 2,4,2[prime]-CBPs; notably absent was 2,2[prime]-CBP. Yet, the total molar concentration of all congeners decreased with time and at 15 months accounted for only 25% of the initial concentration of the parent compound. 2,3,4,5,6-CBP produced 2,3,5,6-, 2,4,6-, and 2,6-CBPs. At 15 months the sum of all congeners accounted for only about 50% of the initial amount of the parent congener. On the other hand, 2,4,5,2[prime],4[prime],5[prime]-CBP yielded six daughter products, including 2,2[prime]-CBP, and did not show any decrease in total molar concentration even at 20 months. 2,4,2[prime],4[prime]-CBP did not show any change at 15 months. These results indicate that anaerobic PCB biotransformation may include mechanisms other than dechlorination and that the mechanisms are congener dependent. Biphenyl was detected with 3,4,3[prime],4[prime]-CBP, indicating complete dechlorination; however, it accounted for <10% of the total molar loss. [sup 14]C-labeled tracer of this congener showed that all radioactivity was in the hexane fraction, suggesting that transformation products were hydrophobic.

  17. High accumulation of PCDD, PCDF, and PCB congeners in marine mammals from Brazil: a serious PCB problem.

    PubMed

    Dorneles, Paulo R; Sanz, Paloma; Eppe, Gauthier; Azevedo, Alexandre F; Bertozzi, Carolina P; Martínez, María A; Secchi, Eduardo R; Barbosa, Lupércio A; Cremer, Marta; Alonso, Mariana B; Torres, João P M; Lailson-Brito, José; Malm, Olaf; Eljarrat, Ethel; Barceló, Damià; Das, Krishna

    2013-10-01

    Blubber samples from three delphinid species (false killer whale, Guiana and rough-toothed dolphin), as well as liver samples from franciscana dolphins were analyzed for dioxins and related compounds (DRCs). Samples were collected from 35 cetaceans stranded or incidentally captured in a highly industrialized and urbanized area (Southeast and Southern Brazilian regions). Dioxin-like PCBs accounted for over 83% of the total TEQ for all cetaceans. Non-ortho coplanar PCBs, for franciscanas (82%), and mono-ortho PCBs (up to 80%), for delphinids, constituted the groups of highest contribution to total TEQ. Regarding franciscana dolphins, significant negative correlations were found between total length (TL) and three variables, ΣTEQ-DRCs, ΣTEQ-PCDF and ΣTEQ non-ortho PCB. An increasing efficiency of the detoxifying activity with the growth of the animal may be a plausible explanation for these findings. This hypothesis is reinforced by the significant negative correlation found between TL and PCB126/PCB169 concentration ratio. DRC concentrations (ng/g lipids) varied from 36 to 3006, for franciscana dolphins, as well as from 356 to 30,776, for delphinids. The sum of dioxin-like and indicator PCBs varied from 34,662 to 279,407 ng/g lipids, for Guiana dolphins from Rio de Janeiro state, which are among the highest PCB concentrations ever reported for cetaceans. The high concentrations found in our study raise concern not only on the conservation of Brazilian coastal cetaceans, but also on the possibility of human health problem due to consumption of fish from Brazilian estuaries. PMID:23827355

  18. Ratio of cord to maternal serum PCB concentrations in relation to their congener-specific physicochemical properties

    PubMed Central

    Lancz, Kinga; Palkovičová, L’ubica; Patayová, Henrieta; Drobná, Beata; Wimmerová, Soňa; Šovčíková, Eva; Kováč, Ján; Farkašová, Dana; Hertz-Picciotto, Irva; Jusko, Todd A.; Trnovec, Tomáš

    2014-01-01

    The aim was to characterize placental transfer of some congeners of polychlorinated biphenyls (PCBs) and to relate human in utero exposure to these pollutants to their physicochemical properties. We included into the study 1134 births during the period 2002–2003 from two highly PCB contaminated districts in eastern Slovakia. Concentrations of 15 PCB congeners (IUPAC No. 28, 52, 101, 123+149, 118, 114, 153, 105, 138+163, 167, 156+171, 157, 180, 170, and 189) in umbilical cord (C) and maternal serum (M) were determined. The C/M ratios were significantly related, either positively or inversely depending on parameter, to the logarithm of partition coefficient octanol-water (KOW), to fusion enthalpy at the melting point, molecular weight, water solubility, total surface area of the molecule, solvent accessible surface area, melting point, molar volume, and molecular electronegativity distance vector. We found an inverse association between log KOW and lipid adjusted log C/M (const= 1.078, b1 = −0.179, p < 0.001, R2 = 0.039). Parameters evaluated were interrelated except fusion enthalpy at the melting point and electron affinity vs. solubility. We discuss the possible role of cholesterol as a transplacental transporter of PCBs. PMID:25277764

  19. Ratio of cord to maternal serum PCB concentrations in relation to their congener-specific physicochemical properties.

    PubMed

    Lancz, Kinga; Murínová, Lubica; Patayová, Henrieta; Drobná, Beata; Wimmerová, Soňa; Sovčíková, Eva; Kováč, Ján; Farkašová, Dana; Hertz-Picciotto, Irva; Jusko, Todd A; Trnovec, Tomáš

    2015-01-01

    The aim was to characterize placental transfer of some congeners of polychlorinated biphenyls (PCBs) and to relate human in utero exposure to these pollutants to their physicochemical properties. We included into the study 1134 births during the period 2002-2003 from two highly PCB contaminated districts in eastern Slovakia. Concentrations of 15 PCB congeners (IUPAC No. 28, 52, 101, 123(+149), 118, 114, 153, 105, 138(+163), 167, 156(+171), 157, 180, 170, and 189) in umbilical cord (C) and maternal serum (M) were determined. The C/M ratios were significantly related, either positively or inversely depending on parameter, to the logarithm of partition coefficient octanol-water (KOW), to fusion enthalpy at the melting point, molecular weight, water solubility, total surface area of the molecule, solvent accessible surface area, melting point, molar volume, and molecular electronegativity distance vector. We found an inverse association between logKOW and lipid adjusted logC/M (const=1.078, b1=-0.179, p<0.001, R(2)=0.039). Parameters evaluated were interrelated except fusion enthalpy at the melting point and electron affinity vs. solubility. We discuss the possible role of cholesterol as a transplacental transporter of PCBs. PMID:25277764

  20. Analysis of 19 PCB congeners in catfish tissue using a modified QuEChERS method with GC-MS/MS.

    PubMed

    Chamkasem, Narong; Lee, Sookwang; Harmon, Tiffany

    2016-02-01

    A simple approach to determine 19 PCB congeners in catfish tissue was presented. A modified QuEChERS method employing high solvent to sample ratio 10:1 was used to improve the extraction recovery of 19 PCB congeners. After salting out by shaking with anhydrous magnesium sulfate and sodium chloride, 1 mL of acetonitrile extract was pipetted into a 2-mL centrifuge tube containing anhydrous magnesium sulfate, primary secondary amine sorbent, and C-18 sorbent. The tube was then shaken and centrifuged to absorb fat and fatty acid residue present in the acetonitrile extract. The acetonitrile extract was analyzed by GC-MS/MS. The excellent sensitivity of GC-MS/MS allows for the direct injection of the samples to detect the low level of the PCB congeners. The method therefore is high throughput, uses fewer consumable lab supplies, and provides excellent sensitivity with an LOQ below 1 ng/g. PMID:26304427

  1. Speciation and quantitation of Aroclors based on PCB congener data: Application to California mussels and white croaker. [Mytilus californianus; Genyonemus lineatus

    SciTech Connect

    Draper, W.M. ); Koszdin, S. )

    1991-08-01

    A procedure for speciation and quantitation of Aroclors in capillary gas-liquid chromatography electron capture detector (GC-ECD) chromatograms is described. Four pentachlorobiphenyls (IUPAC no. PCB-87, -110, -118, and -105) and three heptachlorobiphenyls (PCB-183, -180, and -170) are used as markers of Aroclor 1254 and Aroclor 1260, respectively. The Aroclor content of samples is estimated by comparing the cogener composition with USEPA Aroclor reference materials. In this study, the selected congener approach to Aroclor determination is applied to both California marine mussels (Mytilus californianus and M. Edulis) and white croaker (Genyonemus lineatus) muscle. Both Aroclor 1254 and Aroclor 1260 were present in these species, and the congener patterns matched the Aroclor reference materials closely. In cases where reporting Aroclors is not appropriate, e.g., highly weathered samples, the method also provides PCB congener data.

  2. PCB congener analysis of water and caddisfly larvae (Insecta:Trichoptera) in the upper Hudson River by glass capillary chromatography

    SciTech Connect

    Bush, B.; Simpson, K.W.; Shane, L.; Koblintz, R.R.

    1985-01-01

    The separation and analysis of the constituents of industrially produced polychlorinated biphenyls (PCBs) has been almost exclusively performed using techniques involving packed gas chromatographic columns. However, the packed column chromatograms proved to be inadequate with regard to the separation of the many congeners which compose the complex PCB mixtures. Unlike the packed column methods, a separation technique based upon gas capillary technology produces chromatograms with sharp peaks, and hence accurate analysis is possible according to individual congener concentrations. This capability permitted more precise analysis of macroinvertebrates - specifically aquatic insects in the polluted water of the upper Hudson River. This study examines the presence and relative concentration of 74 congeners in water and caddisfly larvae collected from 3 sites in the Hudson River. Caddisfly larvae (Insecta:Trichoptera) usually dominate the macroinvertebrate communities in riffle habitats of the study area. Their relatively large size and abundance facilitated the acquisition of sufficient biomass for analysis (200 mg wet weight). The sampling was carried out on July 6, 1983 and August 15, 1983.

  3. Record of PCB congeners, sorbents and potential toxicity in core samples in Indiana Harbor and Ship Canal.

    PubMed

    Martinez, Andres; Hornbuckle, Keri C

    2011-10-01

    Indiana Harbor and Ship Canal (IHSC) is an active navigational system that serves a heavily industrial area of southern Lake Michigan. We have determined the amount of polychlorinated biphenyls (PCBs), congener distributions, sorbent types and potential for dioxin-like PCB toxicity from two IHSC sediment cores. Vertical distributions of ΣPCBs (sum of 161 individual or coeluting congeners) ranged from 410 to 91000 and 1800 to 41000 ng g(-1) dry weight (d.w.) for cores 1 and 2, respectively. Core 1 showed its highest accumulation rate for the year ∼1979 and exhibits a strong Aroclor 1248 signal in sediments accumulating over the last 60 years. It appears that from the late 1930s until the beginning of the 1980s there was a large and constant input of PCBs into this system. This pattern differs from lake cores from the Great Lakes region which commonly exhibit a rapid increase, a peak, followed by a sharp decrease in the PCB accumulation rates. Core 2 also has a strong Aroclor 1248 signal in the top layers, but deeper layers show evidence of mixtures of Aroclors and/or weathering processes. High levels of black carbon as a fraction of total organic carbon were found in both cores (median ∼30%), which reflect the long history of local combustion sources. No strong relationship was found between ΣPCB concentration and sorbents. Both cores contain dioxin-like PCBs that are highest in concentration below the surface. The high levels of PCBs in the deep sediments are of concern because of plans to dredge this system. PMID:21899876

  4. Transfer rates and pattern of PCB isomers and congeners and p,p'-DDE from mother to egg in Adelie penguin (Pygoscelis adeliae)

    SciTech Connect

    Tanabe, S.; Surbramanian, A.; Hidaka, H.; Tatsukawa, R.

    1986-03-01

    Mother to egg transfer of PCB isomers and congeners and p,p'-DDE was examined in Adelie Penguin (Pygoscelis adeliae) from Antarctica. Transfer rate to a clutch of two eggs was estimated to be small, accounting to about 4.0% for both PCBs and p,p-DDE to the burden in mother. No significant difference was found in the concentration ratios of individual PCB isomers and congeners between mother and egg, which apparently differed from those between mother and fetus of striped dolphin previously reported.

  5. DEVELOPMERNT OF A LOW-LEVEL ANALYTICAL METHOD FOR CO-PLANAR PCB CONGENERS IN SOIL/SEDIMENT MATRICES USING GC/ECD.

    EPA Science Inventory

    The method development is on-going in the Region 10 Laboratory. The conditions of the separation technique is complete. The MDLs have been determined to be between 3 to 6 ppt in marine sediment for co-planar PCB congeners #77; #81; #126 and #169. The procedure has been used fo...

  6. ACCUMULATION OF PCB CONGENERS IN NESTLING TREE SWALLOWS (TACHYCINETA BICOLOR) ON THE HUDSON RIVER, NEW YORK

    EPA Science Inventory

    Together, these two papers establish a quantitative linkage between PCB concentrations in nestling tree swallows and in the insects that they consume. As such, these papers provide strong support for the use of nestling swallows as a biomonitoring species for exposure assessment ...

  7. Occurrence of non-ortho-, mono-ortho- and di-ortho- substituted PCB congeners in different organs and tissues of polecats (Mustela putorius L. ) from the Netherlands

    SciTech Connect

    Leonards, P.E.G.; Hattum, B. Van; Cofino, W.P. . Inst. for Environmental Studies); Brinkman, U.A. . Dept. of Analytical Chemistry)

    1994-01-01

    The presence and concentrations of non-ortho-, mono-ortho-, and di-ortho--substituted PCB congeners in the pole-cat (n = 7), were investigated. PCBs were extracted with a Soxhlet apparatus. After cleanup the non-ortho-substituted PCB congeners were separated from the other PCBs by HPLC. Determinations were accomplished with GC-ECD or GC-MSD. Patterns of PCBs were examined in different organs and tissues: liver, kidney, muscle, anal gland secretion, mesenteric fat, and subcutaneous fat. Using a multivariate statistical method for data analysis (SIMCA), a significant difference of PCB patterns between anal gland secretion and the other organs and tissues was revealed. Lesser concentrations of congeners with seven and eight chlorine atoms in anal gland secretion were mainly responsible for this phenomenon. A more or less organ- and tissue-specific PCB pattern was observed in all animals. PCB patterns were not dependent on prey choice, which ranged from terrestrial (small rodents) to aquatic (amphibians). This finding implies that PCB patterns in the pole-cat seem to be controlled by metabolic processes rather than diet factors. The total concentration of PCBs in polecats varies widely, two orders of magnitude, from 1 to 3,700 [mu]g/g lipid. In some animals, PCBs exceeded the experimentally determined reproduction effect concentrations of mink and ferrets. Using the toxic equivalent approach, it was observed that planar PCB 126 accounts for 63 to 98% of the toxic equivalents. The results showed that juvenile animals contain greater PCB levels than adult males and females, which might be related to an increased elimination of PCBs in adult animals due to anal gland secretion. High concentrations of PCBs were observed in such secretion. A preliminary model for concentration of PCBs in polecats including this effect is proposed.

  8. Dioxins, furans and AHH-active PCB congeners in eggs of two gull species from the western Mediterranean.

    PubMed

    Pastor, D; Ruiz, X; Barceló, D; Albaigés, J

    1995-09-01

    Polychlorinated biphenyls, dibenzodioxins and dibenzofurans were analysed in eggs of a protected gull species, the Audouin's Gull (Larus audouinii) and compared to those of the Yellow-legged Gull (Larus cachinnans), both breeding in the Western Mediterranean (Ebro Delta and Medes Islands, respectively). Differences in concentrations as well as in congener profiles reflected differences in both habitat and diet of the two species. Levels of AHH-active PCB congeners were lower in Yellow-legged Gull (0.4-1.6 micrograms/g d.w) than in Audouin's Gull eggs (1.2-33.9 micrograms/g d.w.). These concentrations, expressed in international toxic equivalence factors (i-TEQ/g d.w.), were on average 24 times higher in the Audouin's gull. I-TEQ levels due to dioxins were also higher in this species by a factor of ca. 7. I-TEQ levels related to PCBs resulted 90-230 times higher than those of dioxins and furans. Thus, AHH-inducing PCBs might represent even higher toxicological hazards than dioxins and furans to some populations of seabirds. The necessity of assessing the impact of these compounds in rare and protected species is pointed out. PMID:8528648

  9. Effect of nutrient availability on the uptake of PCB congener 2,2',6,6'-tetrachlorobiphenyl by a diatom (Stephanodiscus minutulus) and transfer to a zooplankton (Daphnia pulicaria).

    PubMed

    Lynn, Scott G; Price, David J; Birge, Wesley J; Kilham, Susan S

    2007-06-01

    The objective of this study was to examine the importance of nutrient status of a diatom (Stephanodiscus minutulus) to the uptake of PCB congener #54 (2,2',6,6'-tetrachlorobiphenyl) and the subsequent transfer of PCB to a pelagic grazing zooplankton (Daphnia pulicaria). The algae, which were grown under different nutrient treatments, were then fed to a zooplankton to examine the subsequent food chain transfer of PCB. Algal cultures were grown for at least 2 weeks in a steady state condition in (1) non-limiting, (2) low-Si, (3) low-N or (4) low-P media. Steady state algal cultures were dosed with 0.2 microg L(-1) PCB and were sampled for PCB uptake after 24h. D. pulicaria were allowed to graze on these same cultures for 48 h before being analyzed for PCB body burdens. Low-Si (68% or 0.135 microg L(-1) of PCB) and low-P cultures (62%) had significantly higher percentage uptake of total PCB than the non-limiting (55%) or low-N (52%) treatments. When these values were divided by biochemical or elemental parameters, PCB per lipids (microg microg(-1)) had one of the lowest coefficients of variation (CV) across the four treatments, indicating their importance in PCB uptake. When equal biovolumes of the four different treatment cultures were fed to zooplankton, both the low-N (13.9 ng PCB mg wet weight(-1)) and the low-P (9.6 ng PCB mg wet weight(-1)) grazing D. pulicaria had significantly higher PCB per wet weight than the low-Si (5.6 ng PCB mg wet weight(-1)) and non-limited (2.6 ng PCB mg wet weight(-1)) grazing D. pulicaria. There were no significant differences between algal nutrient treatments in PCB per wet weight of zooplankton grazing on clean algal food in PCB contaminated media. This study indicates that uptake of PCB by phytoplankton can be significantly altered by nutrient availability which subsequently affects transfer to zooplankton, potentially through such responses as grazing rate and lipid assimilation. PMID:17452056

  10. Bioenergetics-based modeling of individual PCB congeners in nestling tree swallows from two contaminated sites on the Upper Hudson River, New York

    USGS Publications Warehouse

    Nichols, J.W.; Echols, K.R.; Tillitt, D.E.; Secord, A.L.; McCarty, J.P.

    2004-01-01

    A bioenergetics-based model was used to simulate the accumulation of total PCBs and 20 PCB congeners by nestling tree swallows at two contaminated sites on the Upper Hudson River, New York. PCB concentrations in birds were calculated as the sum of inherited residues and those acquired through consumption of contaminated insects. Close agreement between simulations and measured residues in 5-, 10-, and 15-day-old nestlings was obtained when PCB concentrations in the diet were set equal to those in food boli taken from adult birds. These simulations were further optimized by fitting the value of a dietary assimilation efficiency constant. Fitted constants for both sites were similar and averaged about 0.7. An evaluation of model performance for individual congeners provided no evidence of metabolic biotransformation. The results of this study are consistent with a companion effort in which principal components analysis was used to compare PCB congener patterns in insects and in tree swallow eggs, nestlings, and adults. Together, these studies establish a quantitative linkage between nestling tree swallows and the insects that they consume and provide strong support for the use of nestling swallows as a biomonitoring species for exposure assessment.

  11. Congener-specific analysis of polychlorinated naphthalenes (PCNs) in the major Chinese technical PCB formulation from a stored Chinese electrical capacitor.

    PubMed

    Huang, Jun; Yu, Gang; Yamauchi, Makoto; Matsumura, Toru; Yamazaki, Norimasa; Weber, Roland

    2015-10-01

    Impurity of polychlorinated naphthalenes (PCNs) in commercial polychlorinated biphenyl (PCB) formulations has been recognized as a relevant source of PCNs in the environment. Congener-specific analysis of most main PCB formulations has been accomplished previously, excluding the Chinese product. The insulating oil in a stored Chinese electric capacitor containing the major Chinese technical formulation "PCB3" was sampled and tested by isotope dilution technology using high-resolution gas chromatography coupled to high-resolution mass spectrometry (HRGC/HRMS). The detected concentration of PCNs in the Chinese PCB oil sample was 1,307.5 μg/g and therefore significantly higher than that reported in PCB formulations from other countries, as well as that in the transformer oil (ASKAREL Nr 1740) additionally tested in the present study for comparison. Based on the measurement, the total amount of PCNs in Chinese PCB3 oil is estimated to be 7.8 t, which would mean only 0.005 % of global production of PCNs of 150,000 t. The homolog profile is similar to those of PCN in Aroclor 1262 and Clophen A40, where the contributions from hexa-CNs and hepta-CNs are predominant and accounted for similar proportions. The Toxic Equivalent Quantity (TEQ) concentration of dioxin-like PCN congeners is 0.47 μg TEQ/g, with the dominant contributors of CN-73 and CN-66/67. This TEQ content from PCN is higher than that in most other PCB formulations with the exemption of the Russian Sovol formulation. The total TEQ in the historic 6,000 t of the Chinese PCB3 formulation is estimated to be 2.8 kg TEQ. PMID:25391227

  12. Diabetes Prevalence in Relation to Serum Concentrations of Polychlorinated Biphenyl (PCB) Congener Groups and Three Chlorinated Pesticides in a Native American Population

    PubMed Central

    Aminov, Zafar; Haase, Richard; Rej, Robert; Schymura, Maria J.; Santiago-Rivera, Azara; Morse, Gayle; DeCaprio, Anthony; Carpenter, David O.

    2016-01-01

    Background: Exposure to persistent organic pollutants (POPs) is known to increase risk of diabetes. Objective: To determine which POPs are most associated with prevalence of diabetes in 601 Akwesasne Native Americans. Methods: Multiple logistic regression analysis was used to assess associations between quartiles of concentrations of 101 polychlorinated biphenyl (PCBs) congeners, congener groups and three chlorinated pesticides [dichlorodiphenyldichloroethylene (DDE), hexachlorobenzene (HCB) and mirex] with diabetes. In Model 1, the relationship between quartiles of exposure and diabetes were adjusted only for sex, age, body mass index (BMI), and total serum lipids. Model 2 included additional adjustment for either total PCBs or total pesticides. Results: Total serum PCB and pesticide concentrations were each significantly associated with prevalence of diabetes when adjusted only for covariates (Model 1), but neither showed a significant OR for highest to lowest quartiles after additional adjustment for the other (Model 2). When applying Model 2 to PCB congener groups and individual pesticides, there were significant omnibus differences between the four quartiles (all ps < 0.042) for most groups, with the exception of penta- and hexachlorobiphenyls, DDE and mirex. However, when comparing highest to lowest quartiles only non- and mono-ortho PCBs [OR = 4.55 (95% CI: 1.48, 13.95)], tri- and tetrachloro PCBs [OR = 3.66 (95% CI: 1.37, –9.78)] and HCB [OR = 2.64 (95% CI: 1.05, 6.61)] showed significant associations with diabetes. Among the non- and mono-ortho congeners, highest to lowest quartile of dioxin TEQs was not significant [OR = 1.82 (95% CI: 0.61, 5.40)] but the OR for the non-dioxin-like congeners was [OR = 5.01 (95% CI: 1.76, 14.24)]. Conclusion: The associations with diabetes after adjustment for other POPs were strongest with the more volatile, non-dioxin-like, low-chlorinated PCB congeners and HCB. Because low-chlorinated congeners are more volatile

  13. Bioaccumulation of six PCB indicator congeners in a heavily polluted water reservoir in Eastern Slovakia: tissue-specific distribution in fish and their parasites.

    PubMed

    Brázová, Tímea; Hanzelová, Vladimíra; Miklisová, Dana

    2012-08-01

    Concentrations of six indicator PCB congeners (IUPAC nos. 28, 52, 101, 138, 153, and 180) were measured in several organs and adipose tissue of a freshwater predatory fishes (European perch, northern pike, pike perch, wels catfish) as well as in nonpredators (common carp, freshwater bream, goldfish, white bream) and in acanthocephalan Acanthocephalus lucii from the water reservoir Zemplínska šírava (Eastern Slovakia), which is considered to be one of the most PCB-contaminated places in Europe. Concentration of PCBs was determined by capillary gas chromatography in samples from May to September 2009. The two-way main-effect ANOVA confirmed that feeding habits of fish (P < 0.00001) and peculiarity of individual fish organs (P < 0.01) affect PCB bioaccumulation. The total amount of PCBs was significantly higher (P < 0.05) in predators compared to nonpredators. Tissue-specific differences were found in PCB accumulation in both fish groups. PCBs were predominantly accumulated in the liver and hard roe. Individual congeners were not distributed homogeneously within the investigated organs and adipose tissue. PCB 153 was present in higher concentrations than the other congeners in all fish organs as well as in adipose tissue comprising an average 31 and 34 % of ΣPCB in predators and nonpredators, respectively. Acanthocephalans, attached to the intestine of perch, absorbed significantly higher concentrations of PCBs (P < 0.001) than the muscles, liver, kidney, brain, and adipose tissue of their host. About 20 times lower amount of PCBs was detected in the liver and almost 3 times in muscles of infected perch. Data on PCB accumulation in perch infected with acanthocephalans demonstrated a decline of PCB values in all organs as well as in adipose tissue compared to noninfected fish. About 20 times lower amount of PCBs was detected in the liver and almost 3 times in muscles of infected perch. Present results could indicate that some parasitic organisms may

  14. Long-range atmospheric transport of PAHs, PCBs and PBDEs to the central and eastern Mediterranean and changes of PCB and PBDE congener patterns in summer 2010

    NASA Astrophysics Data System (ADS)

    Mulder, Marie D.; Heil, Angelika; Kukučka, Petr; Kuta, Jan; Přibylová, Petra; Prokeš, Roman; Lammel, Gerhard

    2015-06-01

    The central and eastern Mediterranean is a receptor area for persistent organic pollutants (POPs) emitted in western, central and eastern Europe, particularly during summer. Atmospheric concentrations of PCBs, DDXs, PBDEs, penta- and hexachlorobenzene were measured during a ship-borne survey in the summer of 2010. The concentration of PCBs (sum of 7 congeners) was 3.61 (2.08-7.72) pg m-3, of which 6.7% was associated with the particulate phase. The mean concentration of DDT isomers and their metabolites, DDE and DDD, was 2.60 (0.46-7.60) pg m-3 (particulate mass fraction θ = 0.097), of penta- and hexachlorobenzene 0.22 (<0.39-2.80) pg m-3 and 6.29 (2.48-24.16) pg m-3, respectively, and of PBDEs (sum of 8 congeners) 7.31 (2.80-19.89) pg m-3. The air masses studied had been transported mostly across central Europe, some crossing western Europe. The observed changes of PCB congener patterns along transport routes are in agreement with the perception that the reaction with the OH radical is dominating PCB atmospheric lifetime, and indicate an overestimation of the second order gas-phase reaction rate coefficient of PCB153 with OH by structure-activity relationship.

  15. An overlooked environmental issue? A review of the inadvertent formation of PCB-11 and other PCB congeners and their occurrence in consumer products and in the environment.

    PubMed

    Vorkamp, Katrin

    2016-01-15

    Polychlorinated biphenyls (PCBs) are banned from production and use in most countries as they are persistent organic pollutants (POPs) of concern for environment and health. Recent research has pointed at a new environment issue resulting from the inadvertent formation of PCBs in certain processes, in particular the pigment production. PCB-11 is a major by-product in these processes, but PCB-28, PCB-52, PCB-77 as well as the nonachlorinated PCBs and PCB-209 have been found in pigments and consumer products as well. In addition to environmental emissions via point sources, in particular related to industrial and municipal wastewater, atmospheric transport seems to be important for the global distribution of PCB-11. Thus, PCB-11 has also been detected in the polar regions. Worldwide air concentrations appear relatively uniform, but maxima have been found in urban and industrialised areas. Data on the uptake and accumulation of PCB-11 in the food chain are still inconclusive: Although food web studies do not show biomagnification, PCB-11 has been detected in humans. The human exposure might originate from the direct contact to consumer products as well as from the omnipresence of PCB-11 in the environment. PMID:26490526

  16. Mussels as bioindicators of PCB pollution: a case study on uptake and release of PCB isomers and congeners in green-lipped mussels (Perna viridis) in Hong Kong waters.

    PubMed

    Tanabe, S; Tatsukawa, R; Phillips, D J

    1987-01-01

    The uptake and release of PCB isomers and congeners were examined in green-lipped mussels (Perna viridis) through a transplantation experiment in two locations in Hong Kong waters. Rapid rates of uptake and release of relatively less lipophilic lower-chlorinated PCBs were observed in the mussels, indicating that the primary mechanism of bioaccumulation of lipophilic pollutants in P. viridis complies with the concept of equilibrium partitioning. Thus, data for contaminant concentrations are most appropriately based upon lipid weights of samples when using mussels as bioindicators of aquatic PCB pollution. Considering the kinetic parameters of PCBs based on lipid weight-related data, it is concluded that P. viridis has the ability to respond rapidly to changes in ambient levels of PCBs. This is significant in determining the usefulness and limitations of mussels as bioindicators for monitoring programmes investigating aquatic pollution by PCBs. PMID:15092720

  17. PCB CONGENERS AND HEXACHLOROBENZENE BIOTA SEDIMENT ACCUMULATING FACTORS FOR MACOMA NASUTA EXPOSED TO SEDIMENTS WITH DIFFERENT TOTAL ORGANIC CARBON CONTENTS

    EPA Science Inventory

    Deposit-feeding marine clams (Macoma nasuta) were exposed for 119d to three sediment types that varied in total organic carbon (TOC) from 0.8 to 2.5%. ediments were spiked with equal concentrations of 13 polychlorinated biphenyl congeners and hexachlorobenzene. issue residues wer...

  18. A Model Using Local Weather Data to Determine the Effective Sampling Volume for PCB Congeners Collected on Passive Air Samplers

    PubMed Central

    2016-01-01

    We have developed and evaluated a mathematical model to determine the effective sampling volumes (Veff) of PCBs and similar compounds captured using polyurethane foam passive air samplers (PUF–PAS). We account for the variability in wind speed, air temperature, and equilibrium partitioning over the course of the deployment of the samplers. The model, provided as an annotated Matlab script, predicts the Veff as a function of physical-chemical properties of each compound and meteorology from the closest Integrated Surface Database (ISD) data set obtained through NOAA’s National Centers for Environmental Information (NCEI). The model was developed to be user-friendly, only requiring basic Matlab knowledge. To illustrate the effectiveness of the model, we evaluated three independent data sets of airborne PCBs simultaneously collected using passive and active samplers: at sites in Chicago, Lancaster, UK, and Toronto, Canada. The model provides Veff values comparable to those using depuration compounds and calibration against active samplers, yielding an average congener specific concentration method ratio (active/passive) of 1.1 ± 1.2. We applied the model to PUF–PAS samples collected in Chicago and show that previous methods can underestimate concentrations of PCBs by up to 40%, especially for long deployments, deployments conducted under warming conditions, and compounds with log Koa values less than 8. PMID:26963482

  19. A Model Using Local Weather Data to Determine the Effective Sampling Volume for PCB Congeners Collected on Passive Air Samplers.

    PubMed

    Herkert, Nicholas J; Martinez, Andres; Hornbuckle, Keri C

    2016-07-01

    We have developed and evaluated a mathematical model to determine the effective sampling volumes (Veff) of PCBs and similar compounds captured using polyurethane foam passive air samplers (PUF-PAS). We account for the variability in wind speed, air temperature, and equilibrium partitioning over the course of the deployment of the samplers. The model, provided as an annotated Matlab script, predicts the Veff as a function of physical-chemical properties of each compound and meteorology from the closest Integrated Surface Database (ISD) data set obtained through NOAA's National Centers for Environmental Information (NCEI). The model was developed to be user-friendly, only requiring basic Matlab knowledge. To illustrate the effectiveness of the model, we evaluated three independent data sets of airborne PCBs simultaneously collected using passive and active samplers: at sites in Chicago, Lancaster, UK, and Toronto, Canada. The model provides Veff values comparable to those using depuration compounds and calibration against active samplers, yielding an average congener specific concentration method ratio (active/passive) of 1.1 ± 1.2. We applied the model to PUF-PAS samples collected in Chicago and show that previous methods can underestimate concentrations of PCBs by up to 40%, especially for long deployments, deployments conducted under warming conditions, and compounds with log Koa values less than 8. PMID:26963482

  20. Contamination profiles of selected PCB congeners, chlorinated pesticides, PCDD/Fs in Antarctic fur seal pups and penguin eggs.

    PubMed

    Schiavone, Alessandra; Corsolini, Simonetta; Borghesi, Nicoletta; Focardi, Silvano

    2009-06-01

    The aim of this study was to investigate levels of some major environmental contaminants, such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and organochlorine pesticides in Antarctic samples. Concentrations of some persistent organic pollutants (POPs) were investigated in Antarctic fur seal pups and eggs of three species of penguins. Dichloro-diphenyl-trichloroethane (DDT) was the main pollutant, followed by PCBs; other organochlorine compounds such as hexachlorobenzene (HCB) and PCDD/Fs were usually found only in minor quantities. Adélie penguin eggs had significantly higher mean PCB concentrations (p<0.05) compared to the other two penguin species, but there was no difference in DDT levels (p>0.05). TEQ values in fur seal blubber in our study were one order of magnitude lower than those considered to elicit physiological effects in aquatic mammals. In general, POP concentrations in our samples suggested that likely the study populations were not currently at risk for adverse health effects, but indicated a clear need for further monitoring to assess the presence and time trend of a broad range of contaminants, mainly emerging POPs thought to be increasing in polar regions. PMID:19375148

  1. Reprint of: Long-range atmospheric transport of PAHs, PCBs and PBDEs to the central and eastern Mediterranean and changes of PCB and PBDE congener patterns in summer 2010

    NASA Astrophysics Data System (ADS)

    Mulder, Marie D.; Heil, Angelika; Kukučka, Petr; Kuta, Jan; Přibylová, Petra; Prokeš, Roman; Lammel, Gerhard

    2015-11-01

    The central and eastern Mediterranean is a receptor area for persistent organic pollutants (POPs) emitted in western, central and eastern Europe, particularly during summer. Atmospheric concentrations of PCBs, DDXs, PBDEs, penta- and hexachlorobenzene were measured during a ship-borne survey in the summer of 2010. The concentration of PCBs (sum of 7 congeners) was 3.61 (2.08-7.72) pg m-3, of which 6.7% was associated with the particulate phase. The mean concentration of DDT isomers and their metabolites, DDE and DDD, was 2.60 (0.46-7.60) pg m-3 (particulate mass fraction θ = 0.097), of penta- and hexachlorobenzene 0.22 (<0.39-2.80) pg m-3 and 6.29 (2.48-24.16) pg m-3, respectively, and of PBDEs (sum of 8 congeners) 7.31 (2.80-19.89) pg m-3. The air masses studied had been transported mostly across central Europe, some crossing western Europe. The observed changes of PCB congener patterns along transport routes are in agreement with the perception that the reaction with the OH radical is dominating PCB atmospheric lifetime, and indicate an overestimation of the second order gas-phase reaction rate coefficient of PCB153 with OH by structure-activity relationship.

  2. BEHAVIORAL ASSESSMENTS OF ADULTS RATS EXPOSED PERINATALLY TO PCB153.

    EPA Science Inventory

    Ortho-substituted polychlorinated biphenyl (PCB) congeners are more neurotoxic in vitro than are non-ortho-substituted PCB congeners. We selected PCB153, a common ortho-substituted PCB congener, to evaluate the neurobehavioral toxicity of this class of PCBs in vivo. Pregnant fema...

  3. EFFECTS OF PCB 84 ATROPISOMERS ON [3H]-PHORBOL ESTER BINDING IN RAT CEREBELLAR GRANULE CELLS AND 45CA2+-UPTAKE IN RAT CEREBELLUM.

    EPA Science Inventory

    There is evidence that Polychlorinated biphenyl (PCB) congeners with ortho substituents have potential to cause neurotoxicity. Many PCB congeners implicated in these neurotoxic effects are chiral. It is currently unknown if the enantiomers of a chiral PCB congeners have differe...

  4. BIOENERGETICS-BASED MODELING OF INDIVIDUAL PCB CONGENERS IN NESTLING TREE SWALLOWS FROM TWO CONTAMINATED SITES ON THE UPPER HUDSON RIVER, NEW YORK

    EPA Science Inventory

    Together, these two papers establish a quantitative linkage between PCB concentrations in nestling tree swallows and in the insects that they consume. As such, these papers provide strong support for the use of nestling swallows as a biomonitoring species for exposure assessment...

  5. PCB biohalogenation under anaerobic conditions

    SciTech Connect

    Gauger, W.K.; McCue, J.J.

    1990-01-01

    The Institute of Gas Technology (IGT) is conducting research on the biodehalogenation of polychlorinated biphenyls (PCB's) under anoxic conditions. Reductive dechlorination of PCB's has been observed in treatments inoculated with Hudson River sediments. Differences in gas chromatograms between time 0 and 4-month incubations indicate pattern shifts of the PCB homologs that constitute Aroclor 1242 from highly chlorinated to lesser chlorinated congeners. Changes in distribution patterns of PCB homologs were also evident. PCB homologs containing 4, 5, 6, and 7 chlorine atoms were shown to decrease over the incubation period, whereas PCB homologs containing 2 and 3 chlorines increased in concentration. 10 refs., 5 figs., 1 tab.

  6. Lack of effects of some individual polybrominated diphenyl ether (PBDE) and polychlorinated biphenyl (PCB) congeners on human lymphocyte functions in vitro.

    PubMed

    Fernlöf, G; Gadhasson, I; Pödra, K; Darnerud, P O; Thuvander, A

    1997-02-01

    The structural similarities between polybrominated diphenyl ethers and immunotoxic halogenated aromatic compounds suggest that the polybrominated diphenyl ethers might affect the immune system. The present study was undertaken to investigate the immunological effects of some purified PBDE-congeners on human lymphocyte function in vitro. Polychlorinated biphenyl congeners were also included in the study. Mitogen-induced DNA synthesis and immunoglobulin synthesis by lymphocytes from blood donors were examined following polybrominated diphenyl ether or polychlorinated biphenyl exposure in vitro in order to determine the immunotoxic potential of these substances. No effects on mitogen-induced proliferation or immunoglobulin synthesis were observed after exposure of cells to concentrations up to 10(-5) M. The negative findings in this study indicate that certain functions of human peripheral lymphocytes, i.e. proliferation and immunoglobulin synthesis, are insensitive to the direct action of polybrominated diphenyl ethers and polychlorinated biphenyls. Our results are in accordance with other recent studies in which no effects on immunological parameters were demonstrated by exposure of lymphocytes to polyhalogenated aromatic hydrocarbons in vitro. PMID:9067487

  7. Levels and distribution pattern of polychlorinated biphenyl (PCB) congeners in razor clams Ensis siliqua (Linnaeus, 1758) from Galicia (north-west Spain) in relation to biometric parameters.

    PubMed

    Carro, N; García, I; Ignacio, M; Mouteira, A

    2006-11-01

    To establish polychlorinated biphenyl (PCB) levels and distribution as well as their relationship to biometric parameters in the razor clam Ensis siliqua (Linnaeus, 1758), 15 individual samples collected from two points sited in the Islas Cies, Ría de Vigo in Galicia, Spain, collected monthly between February 2003 and April 2004, were analysed. PCBs (IUPAC No. 31, 28, 52, 101, 118, 153, 105, 138, 156 and 180) were isolated by Soxhlet extraction. Identification and quantification were performed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography (electron capture detector), respectively. The isomer concentrations in E. siliqua were in the order hexachlorobiphenyls > pentachlorobiphenyls > heptachlorobiphenyls > trichlorobiphenyls > tetrachlorbiphenyls. No correlation was observed between the E. siliqua shell length and PCBs levels. The PCBs 31, 101, 105 and 153 levels were statistically related with some biometric parameters (p < 0.05). Multivariate techniques such as principal component analysis (PCA) show clear seasonal differences between samples. PMID:17071525

  8. Polychlorodibenzodioxin and -furan (PCDD and PCDF) and dioxin-like polychlorobiphenyl (DL-PCB) congener levels in milk of grazing sheep as indicators of the environmental quality of rural areas.

    PubMed

    Brambilla, Gianfranco; Abate, Vittorio; De Filippis, Stefania Paola; Fulgenzi, Anna Rita; Iamiceli, Anna Laura; Mazzette, Alessandro; Miniero, Roberto; Pulina, Giuseppe

    2011-08-10

    An observational study was set up to evaluate how the quality of the environment may influence the levels of of PCDDs, PCDFs, and DL-PCBs in sheep's milk. Seven farms under natural and anthropogenic pressures were considered, along with an inventory of the surrounding regular and natural sources of emissions. Analysis by HRGC-HRMS revealed the highest cumulative levels (2.1 pg of WHO(1998)-TE/g fat) in one organic and one conventional farm, each close to a relevant bushfire. Their pattern was characterized by a noticeable contribution (24%) from mono-ortho-PCB congeners to the cumulative WHO-TE. For the other farms, close to potential anthropogenic sources, the levels recorded in milk ranged from 0.7 to 1.3 pg of WHO-TE/g fat. The health and reproductive indicators were in all herds within the physiological range. Results suggest the environmental quality in extensive farming system should be eligible as a food safety factor, also for organic productions. PMID:21699241

  9. Multiple mechanisms of PCB neurotoxicity

    SciTech Connect

    Carpenter, D.O.; Stoner, C.T.; Lawrence, D.A.

    1996-12-31

    Polychlorinated biphenyls (PCBs) have been implicated in cancer, but many of the symptoms in humans exposed to PCBs are related to the nervous system and behavior. We demonstrated three different direct mechanisms whereby PCBs are neurotoxic in rats. By using flow cytometry, we demonstrated that the orthosubstituted PCB congener 2,4,4{prime}, but neither TCDD nor the coplanar PCB congener 3,4,5,3{prime},4{prime}, causes rapid death of cerebellar granule cells. The ortho-substituted congener 2,4,4{prime} reduced long-term potentiation, an indicator of cognitive potential, in hippocampal brain slices, but a similar effect was observed for the coplanar congener 3,4,3{prime},4{prime}, indicating that this effect may be caused by both ortho- and coplanar congeners by mechanisms presumably not mediated via the Ah receptor. It was previously shown that some ortho-substituted PCB congeners cause a reduction in levels of the neurotransmitter dopamine, and we present in vitro and in vivo evidence that this is due to reduction of synthesis of dopamine via inhibition of the enzyme tyrosine hydroxylase. Thus, PCBs have a variety of mechanisms of primary neurotoxicity, and neurotoxicity is a characteristic of ortho-substituted, non-dioxin-like congeners as well as some coplanar congeners. The relative contribution of each of these mechanisms to the loss of cognitive function in humans exposed to PCBs remains to be determined. 42 refs., 3 figs., 1 tab.

  10. Evaluation and interconversion of various indicator PCB schemes for ∑PCB and dioxin-like PCB toxic equivalent levels in fish.

    PubMed

    Gandhi, Nilima; Bhavsar, Satyendra P; Reiner, Eric J; Chen, Tony; Morse, Dave; Arhonditsis, George B; Drouillard, Ken G

    2015-01-01

    Polychlorinated biphenyls (PCBs) remain chemicals of concern more than three decades after the ban on their production. Technical mixture-based total PCB measurements are unreliable due to weathering and degradation, while detailed full congener specific measurements can be time-consuming and costly for large studies. Measurements using a subset of indicator PCBs (iPCBs) have been considered appropriate; however, inclusion of different PCB congeners in various iPCB schemes makes it challenging to readily compare data. Here, using an extensive data set, we examine the performance of existing iPCB3 (PCB 138, 153, and 180), iPCB6 (iPCB3 plus 28, 52, and 101) and iPCB7 (iPCB6 plus 118) schemes, and new iPCB schemes in estimating total of PCB congeners (∑PCB) and dioxin-like PCB toxic equivalent (dlPCB-TEQ) concentrations in sport fish fillets and the whole body of juvenile fish. The coefficients of determination (R(2)) for regressions conducted using logarithmically transformed data suggest that inclusion of an increased number of PCBs in an iPCB improves relationship with ∑PCB but not dlPCB-TEQs. Overall, novel iPCB3 (PCB 95, 118, and 153), iPCB4 (iPCB3 plus 138) and iPCB5 (iPCB4 plus 110) presented in this study and existing iPCB6 and iPCB7 are the most optimal indicators, while the current iPCB3 should be avoided. Measurement of ∑PCB based on a more detailed analysis (50+ congeners) is also overall a good approach for assessing PCB contamination and to track PCB origin in fish. Relationships among the existing and new iPCB schemes have been presented to facilitate their interconversion. The iPCB6 equiv levels for the 6.5 and 10 pg/g benchmarks of dlPCB-TEQ05 are about 50 and 120 ng/g ww, respectively, which are lower than the corresponding iPCB6 limits of 125 and 300 ng/g ww set by the European Union. PMID:25488397

  11. [Toxicity of polychlorinated biphenyls (PCB)--indoor air pollution by PCB-containing durable elastic sealants].

    PubMed

    Ludewig, S; Kruse, H; Wassermann, O

    1993-01-01

    The widespread use of the persistent and lipophilic polychlorinated biphenyls (PCB) e.g. in electrical engineering, hydraulics and chemistry of the polymers, caused their ubiquitous distribution and accumulation in food chains. Chronic toxicity in humans is known from several incidents of PCB contaminated food. Dose-response experiences, however, remain uncertain due to the technical grade of PCB as a complex mixture of about 150 congeners and many impurities, like polychlorinated dibenzodurans. Some information on the toxicity of a few PCB congeners is available from animal experiments. Large differences in enzyme-inductive efficacy between the PCB congeners rendered the use of toxicity equivalent factors (related to 2,3,7,8-TCDD, "Seveso-Dioxin") necessary. For risk assessment, the use of "sum of PCB", calculated from questionable determinations of 6 minor toxic congeners, is insufficient. Serious problems arise from evaporation of PCB e.g. in technical rooms of telephone companies (in Germany: Telekom) and generally, from sealing materials in buildings. The German Federal Health Administration, BGA, recommends 300 ng total PCB/m3 indoor air as "precautionary value". Since neither the extreme differences in toxicity of the congeners nor bioaccumulation are taken into account, this recommendation of BGA can not be justified any longer. PMID:8219584

  12. LONG-TERM RECOVERY OF PCB-CONTAMINATED SEDIMENTS AT THE LAKE HARTWELL SUPERFUND SITE: PCB DECHLORINATION. 2. RATES AND EXTENT

    EPA Science Inventory

    This paper reports on extensive polychlorinated biphenyl (PCB) dechlorination measured in Lake Hartwell (Pickens County, SC) sediments. Vertical sediment cores were collected from 18 locations in Lake Hartwell (Pickens County, SC) and analyzed in 5-cm increments for PCB congeners...

  13. Distribution patterns of polychlorinated biphenyl congeners in water, sediment and biota from Midway Atoll

    SciTech Connect

    Titus, E.; Scatolini, S.; Cotter, J.; Hope, B.

    1995-12-31

    There are large gaps in the understanding of critical pathways of polychlorinated biphenyl (PCB) transfer from abiotic media into lower trophic level marine organisms and, subsequently to higher marine consumers, particularly for the North Pacific Ocean. In this study, twenty PCB congeners were quantified in surface water, sediment and tissues of marine biota taken from near-shore waters at Midway Atoll. PCB 138, 153, 180, and 187 were the most abundant congeners in all samples analyzed. Bioaccumulation was shifted in favor of higher chlorinated congeners in all species; only aquatic macrophytes displayed significant accumulation of lower chlorinated congeners. Non-ortho substituted congeners with toxic potency were below detection levels in the majority of species. Certain mono-ortho congeners, implicated in marine mammal toxicity, comprised only 4.5% of total congener load in potential forage species.

  14. Congener Profiles of Polychlorinated Biphenyls in Firn and ice From Lomonosovfonna, Svalbard.

    NASA Astrophysics Data System (ADS)

    Hermanson, M. H.; Matthews, K. A.; Isaksson, E.; Muir, D. C.; Winther, J.; van de Wal, R. S.; Steig, E. J.

    2002-12-01

    In April 2000, a 60-meter ice core was drilled on Lomonosovfonna, the highest elevation ice field on Svalbard. The upper 38 meters, dating to about 1920, were analyzed for 108 polychlorinated biphenyl congeners (PCB). The objective was to identify the historic variability of congener patterns and concentration of PCB at Lomonosovfonna. PCB are known to bioaccumulate to significant concentrations in Svalbard wildlife to the extent that health of some organisms may be threatened. Knowing the input history is vital to understanding how present conditions compare to the past. Total PCB concentration in surface snow (0 to 0.5 meter) at Lomonosovfonna in 2000 was 464 pg/L, 60% of the highest concentration (777 pg/L) occurring in about the 1960s, the peak production period for PCB. The surface value was about two times greater than in the layer below (0.5 to 1 meter; 229 pg/L). The surface layer also had a greater amount of more volatile, lower molecular mass (MM) PCB congeners than found in the firn below it. Most PCB found in sub-surface (> 1 meter) Lomonosovfonna ice are from tetra-CB and penta-CB homologues (about 30% of total PCB each) with about 15% of total PCB from hexa-CB. Surface samples (<1 meter) contain more hexa-CB. PCB distribution throughout the profile is dominated by 29 congeners that comprise from 53% to 75% of total PCB, with less in the top meter than in the deeper core. Among the 29 dominant congeners are 7 (and 4 co-eluting) that make up about 25% of total PCB in the top meter and 33 to 40% in deeper layers of the core. These are PCB 49 (and 2 co-eluting PCB 43 + 37), 52, 95, 110, 118, 153 (and two co-eluting PCB, 132 + 105). Some of these congeners are among the most persistent PCB and are often found in other environmental matrices. Our results show that PCB concentrations at Lomonosovfonna are declining from peak periods and that the congener distribution may be shifting away from the 29 dominant congeners to include more high MM PCB

  15. Increasing PCB Radiolysis Rates in Transformer Oil

    SciTech Connect

    Mincher, Bruce Jay

    2002-11-01

    The kinetics of Aroclor 1242 radiolysis in transformer oil, using high-energy electrons, was found to be analogous to that previously measured for individual polychlorinated biphenyl (PCB) congeners irradiated with ó-rays. The plot of the pseudo-first-order rate constant for PCB decomposition versus initial PCB concentration is a power function, with high rate constants for low concentrations. The addition of alkaline isopropanol to transformer oil was found to increase the pseudo-first-order rate constant for PCB decomposition. The rate constant under these conditions is independent of concentration. This may be explained by the establishment of chain reaction dechlorination in the oil.

  16. Increasing PCB radiolysis rates in transformer oil

    NASA Astrophysics Data System (ADS)

    Mincher, Bruce J.; Brey, Richard R.; Rodriguez, René G.; Pristupa, Scott; Ruhter, Aaron

    2002-11-01

    The kinetics of Aroclor 1242 radiolysis in transformer oil, using high-energy electrons, was found to be analogous to that previously measured for individual polychlorinated biphenyl (PCB) congeners irradiated with γ-rays. The plot of the pseudo-first-order rate constant for PCB decomposition versus initial PCB concentration is a power function, with high rate constants for low concentrations. The addition of alkaline isopropanol to transformer oil was found to increase the pseudo-first-order rate constant for PCB decomposition. The rate constant under these conditions is independent of concentration. This may be explained by the establishment of chain reaction dechlorination in the oil.

  17. OXIDATION OF POLYCHLORINATED BIPHENYLS BY LIVER TISSUE SLICES FROM PHENOBARBITAL-PRETREATED MICE IS CONGENER-SPECIFIC AND ATROPSELECTIVE

    PubMed Central

    Wu, Xianai; Duffel, Michael; Lehmler, Hans-Joachim

    2013-01-01

    Mouse models are powerful tools to study the developmental neurotoxicity of polychlorinated biphenyls (PCBs); however, studies of the oxidation of chiral PCB congeners to potentially neurotoxic hydroxylated metabolites (OH-PCBs) in mice have not been reported. Here we investigate the atropselective oxidation of chiral PCB 91 (2,2',3,4',6-pentachlorobiphenyl), PCB 95 (2,2',3,5',6-pentachlorobiphenyl), PCB 132 (2,2',3,3',4,6'-hexachlorobiphenyl), PCB 136 (2,2',3,3',6,6'-hexachlorobiphenyl) and PCB 149 (2,2',3,4',5',6-hexachlorobiphenyl) to OH-PCBs in liver tissue slices prepared from female mice. The metabolite profile of PCB 136 typically followed the rank order 5-OH-PCB > 4-OH-PCB > 4,5-OH-PCB, and metabolite levels increased with PCB concentration and incubation time. A similar OH-PCB profile was observed with the other PCB congeners, with 5-OH-PCB:4-OH-PCB ratios ranging from 2 to 12. More 5-OH-PCB 136 was formed in liver tissue slices obtained from animals pretreated with phenobarbital (P450 2B inducer) or, to a lesser extent, dexamethasone (P450 2B and 3A enzyme inducer) compared to tissue slices prepared from vehicle-pretreated animals. The apparent rate of 5-OH-PCBs formation followed the approximate rank order PCB 149 > PCB 91 > PCB 132 ~ PCB 136 > PCB 95. Atropselective gas chromatography revealed a congener-specific atropisomeric enrichment of major OH-PCB metabolites. Comparison of our results with published OH-PCB patterns and chiral signatures (i.e., the direction and extent of the atropisomeric enrichment) from rat liver microsomal revealed drastic differences between both species, especially following induction of P450 2B enzymes. These species differences in the metabolism of chiral PCBs should be considered in developmental neurotoxicity studies of PCBs. PMID:24107130

  18. Deposition history of polychlorinated biphenyls to the Lomonosovfonna Glacier, Svalbard: a 209 congener analysis.

    PubMed

    Garmash, Olga; Hermanson, Mark H; Isaksson, Elisabeth; Schwikowski, Margit; Divine, Dmitry; Teixeira, Camilla; Muir, Derek C G

    2013-01-01

    A 37 m deep ice core representing 1957-2009 and snow from 2009 to 2010 were collected on the Lomonosovfonna glacier, Svalbard (78.82° N; 17.43° E) and analyzed for 209 polychlorinated biphenyl (PCB) congeners using high-resolution mass spectrometry. Congener profiles in all samples showed the prevalence of tetra- and pentachlorobiphenyls, dominated in all samples by PCB-44, PCB-52, PCB-70 + PCB-74, PCB-87 + PCB-97, PCB-95, PCB-99, PCB-101, and PCB-110. The ∑PCB flux varied over time, but the peak flux, ∼19 pg cm(-2) year(-1) from 1957 to 1966, recurred in 1974-1983, 1998-2009, and 2009-2010. The minimum was 5.75 pg cm(-2) year(-1) in 1989-1998, following a 15 year decline. Peak ∑PCB fluxes here are lower than measured in the Canadian Arctic. The analysis of all 209 congeners revealed that PCB-11 (3,3'-dichlorobiphenyl) was present in all samples, representing 0.9-4.5% of ∑PCB. PCB-11 was not produced in a commercial PCB product, and its source to the Arctic has not been well-characterized; however, our results confirm that the sources to Lomonosovfonna have been active since 1957. The higher fluxes of ∑PCB correspond to periods when average 5 day air mass back trajectories have a frequency of 8-10% and reach 60° N or beyond over northern Europe and western Russia or the North Sea into the U.K. PMID:24073820

  19. Effects of PCB exposure on neuropsychological function in children.

    PubMed Central

    Schantz, Susan L; Widholm, John J; Rice, Deborah C

    2003-01-01

    In the last decade advances in the analytic methods for quantification of polychlorinated biphenyls (PCBs) have resulted in widespread availability of congener-specific analysis procedures, and large amounts of data on PCB congener profiles in soil, air, water, sediments, foodstuffs, and human tissues have become available. These data have revealed that the PCB residues in environmental media and human tissues may not closely resemble any of the commercial PCB mixtures, depending on source of exposure, bioaccumulation through the food chain, and weathering of PCBs in the environment. At the same time, toxicological research has led to a growing awareness that different classes of PCB congeners have different profiles of toxicity. These advances in analytic techniques and toxicological knowledge are beginning to influence the risk assessment process. As the data from ongoing PCB studies assessing the mediators of neurobehavioral outcomes in children are published, the weight of evidence for PCB effects on neurodevelopment is growing. Studies in Taiwan, Michigan (USA), New York (USA), Holland, Germany, and the Faroe Islands have all reported negative associations between prenatal PCB exposure and measures of cognitive functioning in infancy or childhood. The German study also reported a negative association between postnatal PCB exposure and cognitive function in early childhood--a result that had not been found in previous studies. Only one published study in North Carolina (USA) has failed to find an association between PCB exposure and cognitive outcomes. Despite the fact that several more recent studies have used congener-specific analytic techniques, there have been only limited attempts to assess the role of specific PCB congeners or classes of congeners in mediating neurodevelopmental outcomes. From a statistical standpoint, attempts to determine the role of individual congeners in mediating outcomes are hampered by the fact that concentrations of most

  20. Accumulation of polychlorobiphenyl congeners and p,p'-DDE at environmental concentrations by corn and beans

    SciTech Connect

    Shane, L.A.; Bush, B.

    1989-02-01

    The uptake of polychlorinated biphenyl (PCB) congeners present at low concentrations in the environment was investigated in leaf composites of four crop species and final fruits at two sites. All four species preferentially accumulated the same eight congeners, although not in the same degree or rank. No bean species demonstrated a significant increase in accumulation over time, and corn significantly reduced its PCB load over time. Mechanisms are suggested for such behavior. Fruits were 100 times less contaminated than plant leaves.

  1. Chromatographic determination of octanol-water partition coefficients (K/sub ow/'s) for 58 polychlorinated biphenyl congeners

    SciTech Connect

    Rapaport, R.A.; Eisenreich, S.J.

    1984-03-01

    Octanol-water partition coefficients of 58 poly-chlorinated biphenyl (PCB) congeners have been determined by reverse-phase C/sub 18/ high-performance liquid chromatography (HPLC) of Aroclor 1242 and 1254 mixtures. High-resolution glass capillary gas-liquid chromatography was used for the detection of the eluted individual congeners. Some PCB congeners behaved atypically from other organics on reverse-phase HPLC, and empirically derived correction factors were used to adjust K/sub ow/ values. Congener log K/sub ow/ values for PCB's ranged from an average of 4.5 for N/sub Cl/ = 1 to 8.1 for N/sub Cl/ = 7. The environmental implications of PCB K/sub ow/ values and congener behavior on the C /sub 18/ reverse-phase column are discussed. 35 references.

  2. DISTRIBUTION OF PCB 84 ENANTIOMERS IN C57BL/6 MICE

    EPA Science Inventory

    Nineteen of the 209 possible PCB congeners exist as pairs of stable rotational isomers that are enantiomeric to each other. A racemic mixture of PCB atropisomers is present in technical PCB mixtures, thus raising concerns about enantioselective distribution, metabolism, and dispo...

  3. Polychlorinated biphenyl congener patterns in fish near the Hanford Site (Washington State, USA).

    PubMed

    Rodenburg, Lisa A; Delistraty, Damon; Meng, Qingyu

    2015-03-01

    It is well-known that absorption, distribution, metabolism, and excretion (ADME) processes in fish can alter polychlorinated biphenyl (PCB) congener patterns in fish, but these patterns have never been investigated using an advanced source-apportionment tool. In this work, PCB congener patterns in freshwater fish were examined with positive matrix factorization (PMF). PCB congeners were quantified via EPA Method 1668 in fillet and carcass of six species in four study areas in the Columbia River near the Hanford Site. Six factors were resolved with PMF2 software. Depletion and enhancement of PCB congeners in factors, relative to Aroclor 1254, suggested biotransformation (via cytochrome P450) and bioaccumulation in fish, respectively. Notable differences were observed among species and across study locations. For example, sturgeon and whitefish exhibited congener patterns consistent with Aroclor weathering, suggesting potential PCB metabolism in these species. In terms of location, average concentration of total PCBs for all species combined was significantly higher (P < 0.05) at Hanford 100 and 300 areas, relative to upriver and downriver study sites. Furthermore, a distinct PCB signature in sturgeon and whitefish, collected at Hanford study areas, suggests that Hanford is a unique PCB source. PMID:25621866

  4. Polychlorinated biphenyl congener distributions in burbot: evidence for a latitude effect

    USGS Publications Warehouse

    Stapanian, Martin A.; Madenjian, Charles P.; Cott, Peter A.; Rediske, Richard R.; O'Keefe, James P.

    2014-01-01

    We compared the distributions of the congeners of polychlorinated biphenyls (PCBs) detected in whole-body samples of burbot (Lota lota) from Great Slave Lake and Lake Erie. Total PCB concentrations in Great Slave Lake burbot were about 1/60 of the concentrations in Lake Erie burbot. Burbot from Great Slave Lake contained a higher proportion of lower-chlorinated (2-6 chlorines) congeners than did burbot from Lake Erie; the reverse occurred for more highly chlorinated (7-9 chlorines) congeners. Hexachloro congeners, followed by pentachloro congeners, dominated the proportions of total PCB in burbot from both lakes. There were no differences between sexes in whole-body samples or between gonad and somatic tissues in the proportions of the 39 congeners and three sets of co-eluters detected in burbot from Great Slave Lake. In contrast, there were distinct sex differences in congener distributions for older burbot from Lake Erie. Our results generally supported a prediction of higher proportions of lower-chlorinated PCB homologs in organisms in remote polar areas. However, the latitudinal effect on PCB congener distribution may be more complex than that portrayed in previous studies.

  5. ANALYSIS OF CHIRAL PESTICIDES AND POLYCHLORINATED BIPHENYL CONGENERS IN ENVIRONMENTAL SAMPLES

    EPA Science Inventory

    Over 25 % of pesticides and other toxic organic pollutants are chiral, as are 19 of the 209 polychlorinated biphenyl (PCB) congeners; that is, they exist as two mirror image species called enantiomers (PCB enantiomers are called atropisomers). The enantiomers of a chiral compound...

  6. PCBs levels and indicator congeners in children's and adolescents' hair.

    PubMed

    Liang, Baocui; Liu, Xinhui; Hou, Jing; Liang, Gang; Gong, Wenwen; Xu, Diandou; Zhang, Li

    2014-02-01

    Thirty polychlorinated biphenyl (PCB) congeners were determined in the hair samples collected from children (4-12) and adolescents (13-18) of Changchun city, Northeastern China. The mean concentrations of total PCBs and dioxin-like PCBs (dl-PCBs) in the adolescents' hair samples were 161.0 ng g(-1) and 61.7 ng g(-1), which were relatively higher than 43.7 ng g(-1) and 14.6 ng g(-1) in the children's ones. Considering gender difference, the mean concentrations in the girls' hair samples were approximately two times higher than those in the boys' ones for most PCB congeners. The pentachlorinated biphenyl was the dominant homologue. It was found that the levels of total PCBs and dl-PCBs were highly correlated with PCB 118 level in the children's hair samples, and with PCB 114 level in the adolescents' ones. The result demonstrated that the two PCB congeners could be applied as the indicators to evaluate the concentrations of total PCBs and dl-PCBs in children's and adolescents' hair, respectively. PMID:24212066

  7. Development and validation of protocols to differentiate PCB patterns between farmed and wild salmon.

    PubMed

    Yunker, Mark B; Ikonomou, Michael G; Sather, Paula J; Friesen, Erin N; Higgs, Dave A; Dubetz, Cory

    2011-03-15

    Polychlorinated biphenyl (PCB) congener patterns based on full congener PCB analyses of three farmed and five wild species of salmon from coastal British Columbia, Canada are compared using principal components analysis (PCA) and the best fit linear decomposition of the observed PCB composition in terms of Aroclor 1242, 1254, and 1260 end-members. The two complementary analysis methods are used to investigate congener composition pattern differences between species, trophic levels, feeding preferences, and farmed or wild feeding regimes, with the intent of better understanding PCB processes in both salmon and salmon consumers. PCA supports classification of PCB congeners into nine groups based on a) structure activity groups (SAG) related to the bioaccumulation potential in fish-eating mammals, b) Cl number, and c) the numbers of vicinal meta- and para-H. All three factors are needed to interpret congener distributions since SAGs by themselves do not fully explain PCB distributions. Farmed salmon exhibit very similar congener patterns that overlap the PCA and Aroclor composition of their food, while wild salmon separate into two distinct groups, with chinook and "coastal" coho having higher proportions of the higher chlorinated, Aroclor 1260 type, nonmetabolizable congeners, and chum, pink, sockeye, and "remote" coho having higher proportions of the lower chlorinated, more volatile and metabolizable Aroclor 1242 type, congeners. Wild chinook have the highest PCB and toxic equivalent (TEQ) concentrations, and the highest proportions of A1254 A1260, and PCB congeners in the most refractory SAG. Because both "coastal" and "remote" coho groups are likely to be consuming prey of similar size and trophic level, the PCB delivery mechanism (e.g., atmosphere vs runoff) apparently has more influence on the salmon PCB profile than biotransformation, suggesting that the wild chinook PCB profile is determined by feeding preference. Overall, wild salmon distributions primarily

  8. Different effects of PCB101, PCB118, PCB138 and PCB153 alone or mixed in MCF-7 breast cancer cells.

    PubMed

    Radice, Sonia; Chiesara, Enzo; Fucile, Serena; Marabini, Laura

    2008-07-01

    Polychlorinated biphenyls (PCBs) are ubiquitous, persistent environmental contaminants that can be a potential health hazard. In the present study we analyzed the potential estrogenic effect in MCF-7 cells of four biologically relevant PCB congeners, alone or in mixtures, present in dairy products, vegetable oil and fish: PCB101, PCB118, PCB138 and PCB153. The mixture of four PCB was tested at seven different concentrations. We investigated the ability of these PCBs, alone or mixed, to induce cell proliferation, and the level of estrogen-regulated protein pS2, in human MCF-7 breast cancer cells. PCB153 (35 microM) stimulated cell proliferation from 48 h up to day 6, PCB118 (40 microM) only at 48 h, but PCB101 (45 microM) and PCB138 (15 microM) applied to the cells for 6 days had no effect. In contrast, the various concentrations of mixtures significantly reduced cell proliferation at different times. No change in pS2 levels was seen after treatment with the PCBs alone or mixed. In exploring the mechanism of these events, we found that PCB153 induced mitogen-activated protein kinase (MAPK) ERK1/2 at 4, 8 and 12 h, while the antiproliferative effect seemed to be related to an apoptotic action beginning at 12 h and ending at 48 h. These findings indicate that these PCBs alone or mixed have no estrogenic effect in MCF-7 cells, although PCB153 induce an ERK1/2-mediated mitogenic effect. On the contrary the mixture of PCBs induces an antiproliferative effect, ascribable to an apoptotic action. PMID:18508174

  9. Evidence of latitudinal fractionation of polychlorinated biphenyl congeners along the Baltic Sea region

    SciTech Connect

    Agrell, C.; Okla, L.; Larsson, P.; Backe, C.; Wania, F.

    1999-04-15

    Annual cycles of the atmospheric concentrations of PCBs were determined at 16 (mostly rural) stations around the Baltic Sea between 1990 and 1993. The concentration levels of individual congeners were found to be influenced by their physical-chemical properties, ambient temperature, and geographical location. Median levels of PCBs were similar at all stations except at one urban site near Riga. A latitudinal gradient with higher levels in the south was found for the sum of PCB as well as for individual congeners, and the gradient was more pronounced for the low volatility congeners. As a result, the high volatility congeners increased in relative importance with latitude. Generally, PCB concentrations increased with temperature, but slopes of the partial pressure in air versus reciprocal temperature were different between congeners and between stations. In general, the low volatility congeners were more temperature dependent than the high volatility PCB congeners. Steep slopes at a sampling location indicate that the concentration in air is largely determined by diffusive exchange with soils. Lack of a temperature dependence may be due to the influence of long-range transported air masses at remote sites and due to the episodic or random nature of PCB sources at urban sites.

  10. Polychlorinated biphenyl congeners in emergent mayflies from the upper Mississippi River

    USGS Publications Warehouse

    Steingraeber, M.T.; Schwartz, T.R.; Wiener, J.G.; Lebo, J.A.

    1994-01-01

    We determined polychlorinated biphenyls (pcbs) in emergent mayflies (hexagenia bilineata) from a 1250-km reach of the upper mississippi river (umr). Total pcb concentrations (sum of 125 congeners) ranged from 0.21 To 4.1 Mu g/g of dry weight (1.2-29 mu g/g of lipid weight). Concentrations were highest in pools near the twin cities and the quad cities metropolitan areas. Longitudinal movement of pcbs was extensive downstream from the twin cities (175-320 km) but was not apparent downstream from the quad cities. The pcb composition of mayflies was relatively homogeneous throughout most of the river. However, the congener composition in mayflies from two distant locations differed markedly from the other samples and contained a greater abundance of lower molecular weight congeners. Recent pcb discharges from point and nonpoint sources may account for these differences. Emergent mayflies seem to be a useful indicator of pcb contamination of the umr.

  11. DIFFERENTIAL EFFECTS OF POLYCHLORINATED BIPHENYL CONGENERS ON PHOSPHOINOSITIDE HYDROLYSIS AND PROTEIN KINASE C TRANSLOCATION IN RAT CEREBELLAR GRANULE CELLS

    EPA Science Inventory

    Previous reports from our laboratory have suggested that the neuroactivity of some polychlorinated biphenyl (PCB) congeners is associated with perturbations in cellular Ca2+-homeostasis. o characterize the neurochemical effects of PCBs further, the present experiments found that ...

  12. Polychlorinated biphenyl congener distributions in burbot: evidence for a latitude effect.

    PubMed

    Stapanian, Martin A; Madenjian, Charles P; Cott, Peter A; Rediske, Richard R; O'Keefe, James P

    2014-11-01

    The authors compared the distributions of the congeners of polychlorinated biphenyls (PCBs) detected in whole-body samples of burbot (Lota lota) from Great Slave Lake and Lake Erie. Total PCB concentrations in Great Slave Lake burbot were about one-sixtieth of the concentrations in Lake Erie burbot. Burbot from Great Slave Lake contained a higher proportion of lower-chlorinated (2-6 chlorines) congeners than did burbot from Lake Erie; the reverse occurred for more highly chlorinated (7-9 chlorines) congeners. Hexachloro congeners, followed by pentachloro congeners, dominated the proportions of total PCBs in burbot from both lakes. There were no differences between sexes in whole-body samples or between gonad and somatic tissues in the proportions of the 39 congeners and 3 sets of coeluters detected in burbot from Great Slave Lake. In contrast, there were distinct sex differences in congener distributions for older burbot from Lake Erie. The results generally supported a prediction of higher proportions of lower-chlorinated PCB homologs in organisms in remote polar areas. However, the latitudinal effect on PCB congener distribution may be more complex than that portrayed in previous studies. PMID:25088677

  13. Polychlorinated Biphenyl Congeners that Increase the Glucuronidation and Biliary Excretion of Thyroxine Are Distinct from the Congeners that Enhance the Serum Disappearance of Thyroxine

    PubMed Central

    Martin, L. A.; Wilson, D. T.; Reuhl, K. R.; Gallo, M. A.

    2012-01-01

    Polychlorinated biphenyl (PCB) congeners differentially reduce serum thyroxine (T4) in rats, but little is known about their ability to affect biliary excretion of T4. Thus, male Sprague-Dawley rats were orally administered Aroclor-1254, Aroclor-1242 (32 mg/kg per day), PCB-95, PCB-99, PCB-118 (16 mg/kg per day), PCB-126 (40 μg/kg per day), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) (3.9 μg/kg per day), or corn oil for 7 days. Twenty-four hours after the last dose, [125I]T4 was administered intravenously, and blood, bile, and urine samples were collected for quantifying [125I]T4 and in bile [125I]T4 metabolites. Serum T4 concentrations were reduced by all treatments, but dramatic reductions occurred in response to Aroclor-1254, PCB-99 [phenobarbital (PB)-type congener], and PCB-118 (mixed-type congener). None of the treatments increased urinary excretion of [125I]T4. Aroclor-1254, PCB-118, TCDD, and PCB-126 (TCDD-type congener) increased biliary excretion of T4-glucuronide by 850, 756, 710, and 573%, respectively, corresponding to marked induction of hepatic UDP-glucuronosyltransferase (UGT) activity toward T4. PCB-95 and PCB-99 did not induce UGT activity; therefore, the increased biliary excretion of T4-glucuronide was related to the affinity of congeners for the aryl hydrocarbon receptor. The disappearance of [125I]T4 from serum was rapid (within 15-min) and was increased by Aroclor-1254, PCB-99 and PCB-118. Thus, reductions in serum T4 in response to PCBs did not always correspond with UGT activity toward T4 or with increased biliary excretion of T4-glucuronide. The rapid disappearance of [125I]T4 from the serum of rats treated with PB-like PCBs suggests that increased tissue uptake of T4 is an additional mechanism by which PCBs may reduce serum T4. PMID:22187485

  14. Estrogenicity and androgenicity screening of PCB sulfate monoesters in human breast cancer MCF-7 cells.

    PubMed

    Flor, Susanne; He, Xianran; Lehmler, Hans-Joachim; Ludewig, Gabriele

    2016-02-01

    Recent studies identified polychlorinated biphenyl (PCB) sulfate esters as a major product of PCB metabolism. Since hydroxy-PCBs (HO-PCBs), the immediate precursors of PCB sulfates and important contributors to PCB toxicity, were shown to have estrogenic activity, we investigated the estrogenicity/androgenicty of a series of PCB sulfate metabolites. We synthesized the five possible structural sulfate monoester metabolites of PCB 3, a congener shown to be biotransformed to sulfates, a sulfate ester of the paint-specific congener PCB 11, and sulfate monoesters of two HO-PCBs reported to interact with sulfotransferases (PCB 39, no ortho chlorines, and PCB 53, 3 ortho chlorines). We tested these PCB sulfates and 4'-HO-PCB 3 as positive control for estrogenic, androgenic, anti-estrogenic, and anti-androgenic activity in the E- and A-screen with human breast cancer MCF7-derived cells at 100 μM-1 pM concentrations. Only 4'-HO-PCB 3 was highly cytotoxic at 100 μM. We observed structure-activity relationships: compounds with a sulfate group in the chlorine-containing ring of PCB 3 (2PCB 3 and 3PCB 3 sulfate) showed no interaction with the estrogen (ER) and androgen (AR) receptor. The 4'-HO-PCB 3 and its sulfate ester had the highest estrogenic effect, but at 100-fold different concentrations, i.e., 1 and 100 μM, respectively. Four of the PCB sulfates were estrogenic (2'PCB 3, 4'PCB 3, 4'PCB 39, and 4'PCB 53 sulfates; at 100 μM). These sulfates and 3'PCB 3 sulfate also exhibited anti-estrogenic activity, but at nM and pM concentrations. The 4'PCB 3 sulfate (para-para' substituted) had the strongest androgenic activity, followed by 3'PCB 3, 4'PCB 53, 4PCB11, and 4PCB 39 sulfates and the 4'HO-PCB 3. In contrast, anti-androgenicity was only observed with the two compounds that have the sulfate group in ortho- or meta- position in the second ring (2'PCB 3 and 3'PCB 3 sulfate). No dose-response was observed in any screen, but, with exception of estrogenic activity (only seen

  15. Behavioral effects of pre- and postnatal exposure to individual polychlorinated biphenyl congeners in rats

    SciTech Connect

    Holene, E.; Bernhoft, A.; Engen, P.; Nafstad, I. |; Skaare, J.U. |; Sagvolden, T.

    1995-06-01

    Rats were exposed in utero and through mother`s milk either to the coplanar PCB congener 3,3{prime},4,4{prime},5-CB (IUPAC no. 126) or to the mono-ortho-substituted PCB congener 2,3{prime},4,4{prime},5-CB (IUPAC no. 118). The different groups of mothers were exposed to 1 and 5 mg/kg body weight of PCB 118, and 2 {mu}g/kg b.w. of PCB 126 every second day from day 10 to day 20 of gestation. The exposure did not affect the body weight of the dams or the size, weight, sex ratio, or physical development of the offspring. Operant behavioral testing revealed that the PCB-exposed offspring showed both poorer visual discrimination and higher activity level than did the controls. The coplanar PCB 126 congener was the most potent treatment. These results show that both PCB 118 and PCB 126 produced significant neurotoxic effects in the offspring of exposed females in absence of clinical maternotoxic and fetotoxic effects.

  16. Congener-specific accumulation and trophic transfer of polychlorinated biphenyls in spider crab food webs revealed by stable isotope analysis.

    PubMed

    Bodin, N; Le Loc'h, F; Caisey, X; Le Guellec, A-M; Abarnou, A; Loizeau, V; Latrouite, D

    2008-01-01

    Polychlorobiphenyls (PCB) and stable isotopes (delta15N and delta13C) were analyzed in the spider crab (Maja brachydactyla) food web from the Iroise Sea (Western Brittany) and the Seine Bay (Eastern English Channel). PCB concentrations were all significantly higher in organisms from the Seine Bay than those from the Iroise Sea. PCB patterns were strongly related to the feeding mode of the species, and increased influence of higher chlorinated congeners was highlighted with trophic position of the organisms. PCB concentrations (lipid normalized) were significantly related to the isotopically derived trophic level (TL) in spider crab food webs. The highest trophic magnification factors (TMFs) were calculated for the congeners with 2,4,5-substitution, and were lower in the Seine Bay compared to the Iroise Sea. The confrontation of PCB and TL data also revealed biotransformation capacity of decapod crustaceans for specific congeners based on structure-activity relations. PMID:17544187

  17. Concentration levels and congener profiles of polychlorinated biphenyls, pentachlorobenzene, and hexachlorobenzene in commercial pigments.

    PubMed

    Anezaki, Katsunori; Nakano, Takeshi

    2014-01-01

    The concentration levels and congener profiles of polychlorinated biphenyls (PCBs), pentachlorobenzene (PeCBz), and hexachlorobenzene (HxCBz) were assessed in commercially available organic pigments. Among the azo-type pigments tested, PCB-11, which is synthesized from 3,3'-dichlorobendizine, and PCB-52, which is synthesized from 2,2',5,5'-tetrachlorobendizine, were the major congeners detected. It is speculated that these were byproducts of chlorobendizine, which has a very similar structure. The total PCB concentrations in this type of pigment ranged from 0.0070 to 740 mg/kg. Among the phthalocyanine-type pigments, highly chlorinated PCBs, mainly composed of PCB-209, PeCBz, and HxCBz were detected. Their concentration levels ranged from 0.011 to 2.5 mg/kg, 0.0035 to 8.4 mg/kg, and 0.027 to 75 mg/kg, respectively. It is suggested that PeCBz and HxCBz were formed as byproducts and converted into PCBs at the time of synthesizing the phthalocyanine green. For the polycyclic-type pigments that were assessed, a distinctive PCB congener profile was detected that suggested an impact of their raw materials and the organic solvent used in the pigment synthesis. PCB pollution from PCB-11, PCB-52, and PCB-209 pigments is of particular concern; therefore, the monthly variations in atmospheric concentrations of these pollutants were measured in an urban area (Sapporo city) and an industrial area (Muroran city). The study detected a certain level of PCB-11, which is not included in PCB technical mixtures, and revealed continuing PCB pollution originating from pigments in the ambient air. PMID:23852585

  18. Altered stress-induced cortisol levels in goats exposed to polychlorinated biphenyls (PCB 126 and PCB 153) during fetal and postnatal development.

    PubMed

    Zimmer, Karin E; Gutleb, Arno C; Lyche, Jan L; Dahl, Ellen; Oskam, Irma C; Krogenaes, Anette; Skaare, Janneche Utne; Ropstad, Erik

    2009-01-01

    Short-term stress exposure is associated with activation of the hypothalamic-pituitary-adrenal (HPA) axis and a consequent rise in blood glucocorticoids and catecholamines, from the adrenal cortex and medulla, respectively. The HPA axis is a potential target for some persistent organic pollutants, among which polychlorinated biphenyls (PCB) were found to be modulators of the mammalian endocrine system. PCB are distributed globally in the environment, in food chains, and are transferred to the fetuses of pregnant animals and via mother's milk to suckling offspring. In the present study it was postulated that intrauterine and lactational exposure to either of two single congeners of PCB (PCB 153 and PCB 126, respectively) might affect basal cortisol concentrations, and also the cortisol response to short-term stress in adulthood. Thus, pregnant goats were orally exposed to one of these PCB congeners from d 60 of gestation until delivery, and their offspring studied. Low-dose exposure to PCB 153 and PCB 126 resulted in significantly lower mean basal cortisol concentrations in goat offspring during certain periods of pubertal development and their first breeding season. Male goat kids exposed to either PCB congener showed a greater and more prolonged rise in plasma cortisol levels than controls when animals were subjected to mild stress at 9 mo of age using frequent blood sampling. Neither the basal maternal cortisol plasma level nor goat kid adrenal masses were affected by PCB exposure. PMID:19184731

  19. Congener-specific polychlorinated biphenyl patterns in eggs of aquatic birds from the Lower Laguna Madre, Texas

    SciTech Connect

    Mora, M.A.

    1996-06-01

    Eggs from four aquatic bird species nesting in the Lower Laguna Madre, Texas, were collected to determine differences and similarities in the accumulation of congener-specific polychlorinated biphenyls (PCBs) and to evaluate PCB impacts on reproduction. Because of the different toxicities of PCB congeners, it is important to know which congeners contribute most to total PCBs. The predominant PCB congeners were 153, 138, 180, 110, 118, 187, and 92. Collectively, congeners 153, 138, and 180 accounted for 26 to 42% of total PCBs. Congener 153 was the most abundant in Caspian terns (Sterna caspia) and great blue herons (Ardea herodias) and congener 138 was the most abundant in snowy egrets (Egretta thula) and tricolored herons (Egretta tricolor). Principal component analysis indicated a predominance of higher chlorinated biphenyls in Caspian terns and great blue herons and lower chlorinated biphenyls in tricolored herons. Snowy egrets had a predominance of pentachlorobiphenyls. These results suggest that there are differences in PCB congener patterns in closely related species and that these differences are more likely associated with the species` diet rather than metabolism. Total PCBs were significantly greater (p < 0.05) in Caspian terns than in the other species. Overall, PCBs in eggs of birds from the Lower Laguna Madre were below concentrations known to affect bird reproduction.

  20. PCB decomposition and formation in thermal treatment plant equipment.

    PubMed

    Ishikawa, Yukari; Noma, Yukio; Yamamoto, Takashi; Mori, Yoshihito; Sakai, Shin-ichi

    2007-04-01

    In this study we investigated both the decomposition and unintentional formation of polychlorinated biphenyl congeners during combustion experiments of refuse-derived fuel (RDF) and automobile shredder residue (ASR) at several stages in thermal treatment plant equipment composed of a primary combustion chamber, a secondary combustion chamber, and other equipments for flue gas treatment. In both experiments, the unintentional formation of PCB occurred in the primary combustion chamber at the same time as the decomposition of PCB in input samples. By combusting RDF, non-ortho-PCB predominantly formed, whereas ortho-PCB and symmetric chlorinated biphenyls (e.g., #52/69, #87/108, and #151) tended to be decomposed. ASR formed the higher chlorinated biphenyls more than RDF. These by-products from ASR had no structural relation with ortho-chlorine. Lower chlorinated biphenyls appeared as predominant homologues at the final exit site, while all congeners from lower to higher chlorinated PCB were unintentionally formed as by-products in the primary combustion chamber. This result showed that the flue gas treatment equipments effectively removed higher chlorinated PCB. Input marker congeners of RDF were #11, #39, and #68, while those for ASR were #11, #101, #110/120, and #118. Otherwise, combustion marker congeners of RDF were #13/12, #35, #77, and #126, while those for ASR were #170, #194, #206, and #209. While the concentration of PCB increased significantly in the primary combustion chamber, the value of toxicity equivalency quantity for dioxin-like PCB decreased in the secondary combustion chamber and the flue gas treatment equipments. PMID:17134732

  1. The influence of biotransformation on the biomagnification of polychlorobiphenyl congeners in marine mammals and birds

    SciTech Connect

    Boon, J.P.

    1994-12-31

    Results of in-vitro and in-vivo experiments and comparisons of PCB-patterns of prey and predator of field data from the North Sea are presented to explain the influence of biotransformation of PCB congeners on their biomagnification in lung-breathing marine predators. Persistent congeners are taken up proportionally to their relative contribution in prey organisms. Hence molecular descriptors do not play any role here. Metabolizability depends on the presence of vicinal hydrogen atoms and the number of ortho-Cl substituents. The maximum number ortho-Cl atoms still allowing biotransformation differs between seals, cetaceans and seabirds. The majority of congeners with a strong affinity for the Ah-receptor are metabolized in marine mammals, leaving the important question whether the observed effects on reproduction are due to parent compounds or metabolites. Starvation leads to a relative decrease of the metabolizable congeners in the overall pattern.

  2. Toxic congener-specific analysis of PCBs: assessment of toxicity in equivalents of TCDD

    SciTech Connect

    Olafsson, P.G.; Bryan, A.M.

    1987-01-01

    High resolution capillary gas chromatographic analysis of the polychlorobiphenyls (PCBs) present in snapping turtle eggs, provided quantitative data on selected toxic congeners. The concentrations of these congeners have been converted into equivalent toxic concentrations of 2,3,7,8-tetrachloro-p-dibenzodioxin (TCDD). The toxic equivalent factors (TEFs), necessary to effect this transformation were derived from EC/sub 50/ values (half the concentration of the toxic congener required to produce the maximum effect) for aryl hydrocarbon hydroxylase (AHH) induction associated with the corresponding toxic PCB congener or isomer. Summation of the resulting toxic equivalents provided a composite assessment of the toxicity of the PCB mixture in terms of an equivalent concentration of TCDD.

  3. Congener-specific extraction and separation of coplanar PCBs from soil using SPME and capillary GC/MS

    SciTech Connect

    Woolley, C.L.; Mani, V.; Shirey, R.E.; Desorcie, J.L.

    1995-12-31

    The persistence and widespread environmental occurrence of polychlorinated biphenyls (PCBs) in the air, waterways and industrial facilities has created a need for quantitative and qualitative analysis of Aroclor-like mixtures. Although there are 209 possible PCB concerns, only a limited number have shown toxic activity similar to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The World Health Organization recently released a list of the 13 most toxic PCB congeners. Each was rated by its Toxic Equivalency Factor relative to TCDD. These 13 PCB congeners belong to the class of toxic coplanar compounds. These congeners commonly contain chlorosubstitutions in the 3,3{prime},4,4{prime} or 3,4,4{prime} or 3{prime},4,4{prime} positions and either 0, 1, or 2 chloro-substituents in the ortho positions. A new capillary column containing a bonded octylmethyl polysiloxane stationary phase (SPB-Octyl) was evaluated for its propensity to separate coplanar PCB congeners. Solid phase microextraction (SPME), a solvent-free method for extracting volatiles and semi-volatiles from drinking water, waste water, soil and sludge was used to extract PCBs from soil. GC-ECD and GC-MS separations of PCB ladened soils were examined via SPME on the SPB-Octyl column. An approach for selective extraction of coplanar PCB congeners by SPME will be described.

  4. Polychlorinated Biphenyl Sources, Emissions, and Environmental Levels in school Buildings (PCB Workshop presentation)

    EPA Science Inventory

    Measure PCB emission rates from primary sources in laboratory chambersMeasure transport and sorption by materials and dust in laboratory chambersCharacterize PCBs in school building materialsEstimate PCB emission rates from sources in schoolsExamine congener patterns in sources a...

  5. Chamber study of polychlorinated biphenyl (PCB)emissions from caulking materials and light ballasts

    EPA Science Inventory

    The emissions of polychlorinated biphenyl (PCB) congeners from 13 caulk samples were tested in a micro-chamber system. Twelve samples were from PCB-contaminated buildings and one was prepared in the laboratory. Nineteen light ballasts collected from buildings that represent 13 di...

  6. DISTRIBUTION OF PCB 84 ENANTIOMERS IN C56BL/6 MICE

    EPA Science Inventory

    At room temperature, nineteen of the 209 possible PCB congeners exist as pairs of stable rotational isomers that are enantiomeric to each other. A racemic mixture of each of these PCB atropisomers is present in technical mixtures, thus raising concerns about enantioselective dis...

  7. Sampling the Hudson River estuary for PCBs using multiplate artificial substrate samplers and congener-specific gas chromatography in 1991

    SciTech Connect

    Bush, B. . Wadsworth Center for Labs. and Research State Univ. of New York, Albany, NY . School of Public Health); Dzurica, S. . School of Public Health); Wood, L.; Madrigal, E.C. . Wadsworth Center for Labs. and Research)

    1994-08-01

    During the summer of 1991, multiplate artificial substrate samplers were deployed at five locations in the Hudson River from Troy to Poughkeepsie, New York. The sedimentary material that collected on these plates was fractionated and analyzed using a congener-specific method for PCB content. The results were compared intrasite, intersite, and across time. The authors found no difference between the PCB congener distribution patterns in the coarse and fine fractions, as determined by linear regression. They also found little evidence of intersite differentiation--they found no discernible difference in PCB congener distribution, but they did find a difference in magnitude. The 1991 results were then compared to the results from a previous study conducted from 1977 to 1985. They found that over the studied 120 km stretch of the river there has been a 3.7 [+-] 1.2% per annum decline in PCB multiplate residue since 1983.

  8. Linking habitat use of Hudson River striped bass to accumulation of polychlorinated biphenyl congeners

    SciTech Connect

    Ashley, J.T.F.; Secor, D.H.; Zlokovitz, E.; Wales, S.Q.; Baker, J.E.

    2000-03-15

    Since 1976, the commercial striped bass fishery in the Hudson River (NY) has been closed due to total polychlorinated biphenyl (t-PCB) concentrations that exceed the US Food and Drug Administration's advisory level of 2 {micro}g/g-wet weight. Extensive monitoring of Hudson River striped bass demonstrated much more variability in t-PCB levels among individual striped bass than could be explained by their age, sex, or lipid contents. To investigate the possible role of differential habitat use among subpopulations of striped bass in controlling their PCB exposures, 70 fish collected throughout the Hudson River estuary and Long Island Sound in 1994--1995 were analyzed for PCB congeners, and their lifetime migration behaviors were estimated by otolith microchemistry. The mean salinity encountered during the fish's last growth season prior to capture was inversely correlated with the t-PCB body burden. Striped bass permanently residing in fresh and oligohaline portions of the estuary adjacent to known PCB sources had elevated t-PCB levels and congeneric patterns with higher proportions of di-, tri-, and tetrachlorobiphenyls. Conversely, fish spending the majority of their life in more saline waters of the estuary or migrating frequently throughout the salinity gradient contained lower PCB levels composed of more highly chlorinated congeners. The approach used in this study allows habitat use to be incorporated into exposure assessments for anadromous fish species such as striped bass.

  9. Coplanar polychlorinated biphenyl congeners in shark livers from the north-western African Atlantic ocean

    SciTech Connect

    Serrano, R.; Fernandez, M.A.; Hernandez, L.M.

    1997-01-01

    Polychlorinated biphenyls have been widely used by industry throughout the world since 1930. Although their use has been banned in many countries since the late 1970s, they still represent an important class of priority pollutants due to their persistence. Most open uses of these chemicals have been severely curtailed in industrialized nations, but a considerable fraction of past productions is probably still cycling in the ecosphere. In recent years, attention has been focused on the toxicity of PCBs, especially of those congeners showing similar toxicity as the polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDFs). It has been shown that PCB congeners` toxicity largely depends on the chlorine substitution pattern. The most toxic PCB cogeners are those with two para chlorines, at least two meta chlorines and 0-2 ortho chlorines. These so-called {open_quotes}coplanar{close_quotes} (non- mono- and di-ortho) PCB cogeners are able to obtain planar conformation. Recently, toxic equivalence factors have been assigned to coplanar PCBs. Thus determination of individual PCB cogeners is important for evaluating the toxic potentials of PCB residues in, for example, wildlife. This paper presents preliminary results of a study looking at levels of PCB congeners, including coplanar ones, in the liver of six shark species, collected in the North African Atlantic Ocean. 15 refs., 2 figs., 2 tabs.

  10. Differential toxicity of three polychlorinated biphenyl congeners in developing sea urchin embryos

    SciTech Connect

    Schweitzer, L.E.; Suffet, I.H.; Hose, J.E.; Bay, S.M.

    1997-07-01

    The relationship between body burden and toxicity of three individual polychlorinated biphenyl (PCB) congeners in developing sea urchin embryos was investigated to evaluate the validity of current predictive models of PCB toxicity in an invertebrate system. Body burdens of radiolabeled PCB congeners (IUPAC-47, 77, and 153) accumulated from a seawater were used to determine median effective concentrations (EC50s) for developmental and cytogenetic effects following a 72-h exposure. Congener 47, a di-ortho-substituted tetrachlorobiphenyl, was found to be at least four times more toxic than congener 77, a non-ortho-substituted (coplanar) tetrachlorobiphenyl, with EC50s of 47 and >218 mmol/kg, respectively, using an embryo development assay. This result contradicts the structure-activity prediction of the mammalian-based toxic equivalents (TEQs) approach, demonstrating the need for an ecotoxicologic model. Congener 153, a di-ortho-substituted hexachlorobiphenyl, was virtually nontoxic in terms of developmental effects at the highest dose achievable at its limit of water solubility. Cytogenetic analysis was a more sensitive method for assessing toxicity than the embryo development assay. Dose-response relationships were established with mitotic activity being the most sensitive endpoint because the PCBs appeared to inhibit mitosis. At the highest doses, complete mitotic arrest was observed. Congener 77 was found to be at least two times more toxic than congener 153 but not as toxic as congener 47 using mitotic activity as the endpoint for toxicity. Thus, the developmental and cytogenetic endpoints ranked the toxicity of the congeners similarly, but established different EC50s.

  11. PCB metabolism by ectomycorrhizal fungi

    SciTech Connect

    Donnelly, P.K.; Fletcher, J.S.

    1995-04-01

    Since 1976 the use of polychlorinated biphenyls (PCBs) has been banned in the U.S. Prior to this, commercial mixtures (Aroclors) had been used extensively as an industrial lubricant because of their nonflammable, nonreactive properties. These same properties are responsible for their persistent in the environment where they bind to soil particles and resist biodegradation. Decontamination of PCB-laden soil is expensive with excavation followed by either storage or incineration as the primary means of remediation. The use of microorganisms for PCB bioremediation has been gaining popularity in the past few years. Bacteria and/or fungi isolated from environmental samples have been used to degrade PCBs under laboratory conditions, but in field trials they have not been as effective. The most common explanation for the poor performance of PCB-degrading organisms introduced at contaminated sites is that they do not compete well with the existing populations. Plant-ectomycorrhizal systems may overcome this problem. Introduction and cultivation of a known host plant at a contaminated site has the potential of providing a survival advantage for ectomycorrhizal fungi that normally colonize the roots of the introduced plant. Ectomycorrhizal fungi exist naturally in the soil and normally grow in association with the roots of a host plant in a mutualistic symbiotic relationship. Preliminary in vitro examination of this group of fungi for their ability to enzymatically degrade xenobiotics is very promising. In vivo studies have shown that some of these fungi have the ability to degrade chlorinated, aromatic compounds, such as 2,4-D and atrazine. The aspect of ectomycorrhizal metabolism was investigated further in the current study by determining the ability of 21 different fungi to metabolize 19 different PCB congeners with varying chlorine content and substitution patterns. 13 refs., 1 fig., 2 tabs.

  12. Modeling trapping mechanism for PCB adsorption on activated carbon

    NASA Astrophysics Data System (ADS)

    Jensen, Bjørnar; Kvamme, Bjørn; Kuznetsova, Tatyana; Oterhals, A.˚ge

    2012-12-01

    The levels of polychlorinated dibenzo-p-dioxin, polychlorinated dibenzofuran (PCDD/F) and dioxin-like polychlorinated biphenyl (DL-PCB) in fishmeal and fish oil produced for use in feed for salmon is above present European legislation levels in some regions of the world and different decontamination approaches have been proposed [1]. One of these is adsorption on activated carbon. This approach appears to be efficient for adsorption of PCDD/F but less efficient for DL-PCB [2]. Activated carbon consists of slit pores with average sizes of 20 - 50 Ångstroms. One hypothesis [2] for the mechanism of trapping DL-PCB is reduced ability for intramolecular movements of the PCB molecules inside the slit pores. In order to investigate this hypothesis we have used quantum mechanics [3] to characterize two DL-PCB congeners, respectively congener 77 (3,3',4,4'-Tetrachlorobiphenyl) and congener 118 (2,3',4,4',5-Pentachlorobiphenyl) and Triolein (18:1) [4] as a major constituent of the solvent fish oil. A model for activated carbon was constructed using a crystal structure of graphite from the American Mineralogist Crystal Structure Database [5]. The crystal structure used was originally from Wyckoff [6]. A small program had to be written to generate the desired graphite structure as it contains no less than 31232 Carbon atoms. Partial atomic charges were estimated using QM with DFT/B3LYP/6-311+g** and SM6 [7].

  13. Polychlorinated biphenyls (PCB), thyroid hormones and cytokines in construction workers removing old elastic sealants

    PubMed Central

    Lundholm, Cecilia; Johansson, Niklas; Wingfors, Håkan

    2008-01-01

    Objectives To estimate the internal PCB level in Swedish workers specialised in PCB abatement in buildings and to measure possible effects of PCB on thyroid function and aspects of the immune system. Methods Thirty six of 40 eligible workers (90%) removing old elastic sealants containing PCB and 33 control construction workers provided blood samples for determination of 19 PCB congeners and some other organochlorine compounds (hexachlorobenzene and p,p′-DDE), thyroid function hormones and a set of cytokines. The PCB exposed group was reinvestigated after 10 months for a trend assessment. Results The sum of 19 PCB congeners in blood plasma from the occupationally PCB-exposed group was twice the level in the controls (geometric mean 580 vs. 260 ng/g lipid; P < 0.001), and there was also some difference in p,p′-DDE between the groups while the lipid-adjusted hexachlorobenzene levels were of the same magnitude. No statistically significant increase in overall PCB levels was observed in the abatement workers at follow-up and some congeners even declined. Thyroid function was not associated with PCB exposure at the current levels and this applied also to the cytokines investigated. Conclusions Swedish workers removing old elastic sealants with PCB have a higher internal PCB load than unexposed colleague construction workers, tentatively secondary to historical exposure. A system of protective measures seemed to be efficient since no further increase was noted after a longish period of additional exposure. There was no evidence of thyroid function or immune system involvement, as expressed by a set of cytokines, at the low PCB levels recorded. PMID:18350309

  14. Evidence for unique and ubiquitous environmental sources of 3,3'-dichlorobiphenyl (PCB 11).

    PubMed

    Rodenburg, Lisa A; Guo, Jia; Du, Songyan; Cavallo, Gregory J

    2010-04-15

    The non-Aroclor congener 3,3'-dichlorobiphenyl (PCB 11) has been recently detected in air, water, biota, sediment, and suspended sediment. Although it has been known since at least the 1970s that this congener is produced inadvertently during the production of diarylide yellow pigments, this work presents the first evidence that the use of these pigments in consumer goods results in the dispersion of PCB 11 throughout the environment at levels that are problematic in terms of achieving water quality standards for the sum of polychlorinated biphenyls (PCBs). In this work, PCB 11 is measured at ppb levels in consumer goods that are likely to be discarded in ways that allow them to enter wastewater treatment plants and combined sewer overflows, including newspapers, magazines, cardboard boxes used for food packaging, and plastic bags. Also, using data sets acquired for the purpose of calculating total maximum daily loads (TMDLs) for PCBs, PCB 11 loads to the New York/New Jersey Harbor and Delaware River are calculated. Despite the fact that there are no known manufacturers of diarylide yellow pigments in the Delaware River watershed, the loads of PCB 11 to the Delaware River exceed the TMDL for the sum of PCBs by nearly a factor of 2. The ratio of PCB 11 to a characteristic dechlorination end product, PCB 4 (2,2'-dichlorobiphenyl), in these data sets indicates that dechlorination is not a significant source of PCB 11 in these systems. In the upper Hudson River, where extensive dechlorination of heavy PCB congeners occurs, the ratio is just 0.012. In contrast, downstream in the NY/NJ Harbor as well as in the Delaware River the ratio is much higher and more variable. Pigment use therefore appears to be the main source of PCB 11 in these systems, and this congener is likely to present a significant obstacle to achieving PCB water quality standards throughout the United States. PMID:20384375

  15. Inhalation and Dietary Exposure to PCBs in Urban and Rural Cohorts via Congener-Specific Measurements

    PubMed Central

    2015-01-01

    Polychlorinated biphenyls (PCBs) are a group of 209 persistent organic pollutants, whose documented carcinogenic, neurological, and respiratory toxicities are expansive and growing. However, PCB inhalation exposure assessments have been lacking for North American ambient conditions and lower-chlorinated congeners. We assessed congener-specific inhalation and dietary exposure for 78 adolescent children and their mothers (n = 68) in the Airborne Exposure to Semi-volatile Organic Pollutants (AESOP) Study. Congener-specific PCB inhalation exposure was modeled using 293 measurements of indoor and outdoor airborne PCB concentrations at homes and schools, analyzed via tandem quadrupole GS-MS/MS, combined with questionnaire data from the AESOP Study. Dietary exposure was modeled using Canadian Total Diet Survey PCB concentrations and National Health and Nutrition Examination Survey (NHANES) food ingestion rates. For ∑PCB, dietary exposure dominates. For individual lower-chlorinated congeners (e.g., PCBs 40+41+71, 52), inhalation exposure was as high as one-third of the total (dietary+inhalation) exposure. ∑PCB inhalation (geometric mean (SE)) was greater for urban mothers (7.1 (1.2) μg yr–1) and children (12.0 (1.2) μg yr–1) than for rural mothers (2.4 (0.4) μg yr–1) and children (8.9 (0.3) μg yr–1). Schools attended by AESOP Study children had higher indoor PCB concentrations than did homes, and account for the majority of children’s inhalation exposure. PMID:25510359

  16. A mass spectroscopic method for analysis of AHH-inducing and other polychlorinated biphenyl congeners and selected pesticides in fish

    USGS Publications Warehouse

    Schmidt, Larry J.; Hesselberg, Robert J.

    1992-01-01

    The 209 polychlorinated biphenyl (PCB) congeners exhibit a wide range in toxicity to fish, birds, and mammals. This paper discusses the use of gas chromatography/mass spectrometry negative chemical ionization (GC/MS-NCI) to quantify congeners of highly suspected toxicity such as IUPAC #77 (3,3',4,4'-tetrachlorobiphenyl) and #126 (3,3',4,4',5-pentachlorobiphenyl). GC/MS analysis time needed to produce the necessary resolution was reduced to 1 h per sample or standard, allowing an autosampler to inject 12 samples in 24 hours, plus 12 standards/QC samples. Identification and quantification of some 60+ congeners and several selected pesticides and estimation of total PCBs are also possible within the 1 h analysis. For congeners of high chlorination (penta through octa), the method exhibited excellent sensitivity, such that we could not locate a fish which exhibited PCB levels below our calibrated quantitation range. NCI was not as sensitive for mono through tri and for some tetrachlorinated PCB congeners, an exception being PCB #77, for which sensitivity was of the same order as for the more highly chlorinated biphenyls. Long term stability was excellent. Over a 6-mo period, results of replicate analyses for PCB congeners and pesticides in a composited sample of lake trout (Salvelinus namaycush) from Lake Michigan had a relative standard deviation of 12% of the mean. Over the same time period, mean recoveries for samples spiked at concentrations similar to those in Lake Michigan lake trout were 90-102%. Response was linear over a wide range of concentrations for each of the analyzed compounds. This method is now being used for routine analysis of PCB congeners and selected pesticides in our laboratory.

  17. Polychlorinated biphenyl congener patterns in tree swallows (Tachycineta bicolor) nesting in the Housatonic River watershed, western Massachusetts, USA, using a novel statistical approach.

    PubMed

    Custer, Christine M; Read, Lorraine B

    2006-07-01

    A novel application of a commonly used statistical approach was used to examine differences in polychlorinated biphenyl (PCB) congener patterns among locations and sample matrices in tree swallows (Tachycineta bicolor) nesting in the Housatonic River watershed in western Massachusetts, USA. The most prevalent PCB congeners in tree swallow tissue samples from the Housatonic River watershed were Ballsmitter Zell numbers 153, 138, 180, 187, 149, 101, and 170. These congeners were seven of the eight most prevalent congeners in Aroclor 1260, the PCB mixture that was the primary source of contamination in the Housatonic River system. Using paired-Euclidean distances and tolerance limits, it was demonstrated that congener patterns in swallow tissues from sites on the main stem of the Housatonic River were more similar to one another than to two sites upstream of the contamination or from a nearby reference area. The congener patterns also differed between the reference area and the two upstream tributaries and between the two tributaries. These pattern differences were the same in both pipper (eggs or just hatched nestlings) and 12-day-old nestling samples. Lower-chlorinated congeners appeared to be metabolized in nestlings and pippers compared to diet, and metabolized more in pippers compared to nestlings. Euclidean distances and tolerance limits provide a simple and statistically valid method to compare PCB congener patterns among groups. PMID:16377044

  18. The PCB mark

    SciTech Connect

    1994-12-01

    Polychlorinated biphenyls (PCBs) are a class of organic chemicals that had become widely used in industrial applications due to their practical physical and chemical properties. Historical uses of PCBs include dielectric fluids (used in utility transformers, capacitors, etc.), hydraulic fluids, and other applications requiring stable, fire-retardant materials. Due to findings that PCBs may cause adverse health effects and due to their persistence and accumulation in the environment. The Toxic Substances Control Act (TSCA), enacted on October 11, 1976, banned the manufacture of PCBs after 1978 [Section 6(e)]. The first PCB regulations, promulgated at 40 CFR Part 761, were finalized on February 17, 1978. These PCB regulations include requirements specifying disposal methods and marking (labeling) procedures, and controlling PCB use. To assist the Department of Energy (DOE) in its efforts to comply with the TSCA statute and implementing regulations, the Office of Environmental Guidance has prepared the document ``Guidance on the Management of Polychlorinated Biphenyls (PCBs).`` That document explains the requirements specified in the statute and regulations for managing PCBs including PCB use, storage, transport, and disposal. The requirements outlined at 40 CFR 761.40 through 761.45 specify marking requirements for most PCB items (i.e., any PCB Article, PCB Container, PCB Article Container, or PCB Equipment that contains PCBs). Most PCB items require PCB marks, which are defined as a descriptive name, instructions, cautions, or other information applied to PCB Items or other objects subject to these regulations. The marking regulations include requirements for PCB marks on PCB Items, storage areas, and temporary storage areas. This Information Brief supplements the PCB guidance document by responding to common questions concerning marking requirements for PCBs. It is one of a series of Information Briefs pertinent to PCB management issues.

  19. Planar PCB Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review

    USGS Publications Warehouse

    Eisler, R.; Belisle, A.A.

    1996-01-01

    Ecological and toxicological aspects of polychlorinated biphenyls (PCBs) in the environment are reviewed with emphasis on biologically active congeners and fish and wildlife. Subtopics include sources and uses, chemical and biochemical properties, concentrations in field collections, lethal and sublethal effects, and recommendations for the protection of sensitive resources. All production of PCBs in the United States ceased in 1977. Of the 1.2 million tons of PCBs manufactured to date, about 65% are still in use in electrical equipment and 31% in various environmental compartments, and 4% were degraded or incinerated. The 209 PCB congeners and their metabolites show wide differences in biological effects. A significant part of the toxicity associated with commercial PCB mixtures is related to the presence of about 20 planar congeners, i.e., congeners without chlorine substitution in the ortho position. Toxic planar congeners, like other PCB congeners, have been detected in virtually all analyzed samples, regardless of collection locale. Planar PCB concentrations were usually highest in samples from near urban areas and in fat and liver tissues, filter-feeding bivalve mollusks, fish-eating birds, and carnivorous marine mammals. Adverse effects of planar PCBs on growth, survival, and reproduction are highly variable because of numerous biotic and abiotic modifiers, including interaction with other chemicals. In general, embryos and juveniles were the most sensitive stages tested to planar PCBs, and the chinook salmon, domestic chicken, mink, rhesus macaque, and laboratory white rat were among the most sensitive species. for protection of natural resources, most authorities now recommend (1) analyzation of environmental samples for planar and other potentially hazardous congeners; (2) exposure studies with representative species and specific congeners, alone and in combination with other environmental contaminants; (3) clarification of existing structure

  20. Dynamics of PCB removal and detoxification in historically contaminated soils amended with activated carbon.

    PubMed

    Vasilyeva, Galina K; Strijakova, Elena R; Nikolaeva, Svetlana N; Lebedev, Albert T; Shea, Patrick J

    2010-03-01

    Activated carbon (AC) can help overcome toxicity of pollutants to microbes and facilitate soil bioremediation. We used this approach to treat a Histosol and an Alluvial soil historically contaminated with PCB (4190 and 1585 mg kg(-1), respectively; primarily tri-, tetra- and pentachlorinated congeners). Results confirmed PCB persistence; reductions in PCB extractable from control and AC-amended soils were mostly due to a decrease in tri- and to some extent tetrachlorinated congeners as well as formation of a bound fraction. Mechanisms of PCB binding by soil and AC were different. In addition to microbial degradation of less chlorinated congeners, we postulate AC catalyzed dechlorination of higher chlorinated congeners. A large decrease in bioavailable PCB in AC-amended soils was demonstrated by greater clover germination and biomass. Phytotoxicity was low in treated soils but remained high in untreated soils for the duration of a 39-month experiment. These observations indicate the utility of AC for remediation of soils historically contaminated with PCB. PMID:19897290

  1. Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake whitefish (Coregonus clupeaformis) from their food

    USGS Publications Warehouse

    Madenjian, C.P.; O'Connor, D.V.; Rediske, R.R.; O'Keefe, J. P.; Pothoven, S.A.

    2008-01-01

    Lake whitefish (Coregonus clupeaformis) were fed rainbow smelt (Osmerus mordax) in four laboratory tanks over a 133-d experiment. At the start of the experiment, 10 to 14 of the fish in each tank were sacrificed, and the concentrations of 40 polychlorinated biphenyl (PCB) congeners within these fish were determined. Polychlorinated biphenyl congener concentrations were also determined in the 15 lake whitefish remaining in each of the four tanks at the end of the experiment as well as in the rainbow smelt fed to the lake whitefish. Each lake whitefish was weighed at the start and the end of the experiment, and the amount of food eaten by the lake whitefish during the experiment was tracked. Using these measurements, net trophic transfer efficiency (??) from the rainbow smelt to the lake whitefish in each of the four tanks was calculated for each of the 40 PCB congeners. Results showed that ?? decreased exponentially as log KOW for the congeners increased from 6 to 8. Further, ?? averaged 0.70 for the tetrachloro congeners but averaged only 0.45 for the higher chlorinated congeners. ?? 2008 SETAC.

  2. Comparison of the in vitro effects of TCDD, PCB 126 and PCB 153 on thyroid-restricted gene expression and thyroid hormone secretion by the chicken thyroid gland.

    PubMed

    Katarzyńska, Dorota; Hrabia, Anna; Kowalik, Kinga; Sechman, Andrzej

    2015-03-01

    The aim of this study was to compare the in vitro effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3',4,4',5-pentachlorobiphenyl (PCB 126; a coplanar PCB congener) and 2,2'4,4',5,5'-hexachlorobiphenyl (PCB153; non-coplanar PCB) on mRNA expression of thyroid-restricted genes, i.e. sodium iodide symporter (NIS), thyroid peroxidase (TPO) and thyroglobulin (TG), and thyroid hormone secretion from the thyroid gland of the laying chicken. Relative expression levels of NIS, TG and TPO genes and thyroxine (T4) and triiodothyronine (T3) secretion from the thyroidal explants were quantified by the real-time qPCR and RIA methods, respectively. In comparison with the control group, TCDD and PCB 126 significantly increased mRNA expression of TPO and TG genes. TCDD did not affect NIS mRNA levels, but PCB 126 decreased its expression. No effect of PCB 153 on the expression of these genes was observed. TCDD and PCB 126 significantly decreased T4 and T3 secretion. There was no significant effect of PCB 153 on these hormone secretions. In conclusion, the results obtained show that in comparison with non-coplanar PCB 153, TCDD and coplanar PCB 126 can directly affect thyroid hormone synthesis and secretion, and in consequence, they may disrupt the endocrine function of the thyroid gland of the laying chicken. PMID:25682001

  3. Tracking polychlorinated biphenyls (PCBs) congener patterns in Newark Bay surface sediment using principal component analysis (PCA) and positive matrix factorization (PMF).

    PubMed

    Saba, Tarek; Su, Steave

    2013-09-15

    PCB congener data for Newark Bay surface sediments were analyzed using PCA and PMF, and relationships between the outcomes from these two techniques were explored. The PCA scores plot separated the Lower Passaic River Mouth samples from North Newark Bay, thus indicating dissimilarity. Although PCA was able to identify subareas in the Bay system with specific PCB congener patterns (e.g., higher chlorinated congeners in Elizabeth River), further conclusions reading potential PCB source profiles or potential upland source areas were not clear for the PCA scores plot. PMF identified five source factors, and explained the Bay sample congener profiles as a mix of these Factors. This PMF solution was equivalent to (1) defining an envelope that encompasses all samples on the PCA scores plot, (2) defining source factors that plot on that envelope, and (3) explaining the congener profile for each Bay sediment sample (inside the scores plot envelope) as a mix of factors. PMF analysis allowed identifying characteristic features in the source factor congener distributions that allowed tracking of source factors to shoreline areas where PCB inputs to the Bay may have originated. The combined analysis from PCA and PMF showed that direct discharges to the Bay are likely the dominant sources of PCBs to the sediment. Review of historical upland activities and regulatory files will be needed, in addition to the PCA and PMF analysis, to fully reconstruct the history of operations and PCB releases around the Newark Bay area that impacted the Bay sediment. PMID:23831929

  4. Polychlorinated biphenyl congener patterns in tree swallows (Tachycineta bicolor) nesting in the Housatonic River watershed, western Massachusetts, USA, using a novel statistical approach

    USGS Publications Warehouse

    Custer, Christine M.; Read, L.B.

    2006-01-01

    A novel application of a commonly used statistical approach was used to examine differences in polychlorinated biphenyl (PCB) congener Patterns among locations and sample matrices in tree swallows (Tachycineta bicolor) nesting in the Housatonic River watershed in western Massachusetts. USA. The most prevalent PCB congeners in tree swallow tissue samples from the Housatonic River watershed were Ballsmitter Zell numbers 153. 138 180, 187 149, 101, and 170. These congeners were seven of the eight most prevalent congeners in Aroclor (R) 1260, the PCB mixture that was the primary source of contamination in the Housatonic River system. Using paired-Euclidean distances and tolerance limits, it was demonstrated that conuener patterns in swallow tissues from sites on the main stem of the Housatonic River were more similar to one another than to two sites upstream of the contamination or from a nearby reference area. The congener patterns also differed between the reference area and the two upstream tributaries and between the two tributaries. These pattern differences were the same in both pipper (eggs or just hatched nestlings) and 12-day-old nestling samples. Lower-chlorinated congeners appeared to be metabolized in nestlings and pippers compared to diet. and metabolized more in pippers compared to nestlings. Euclidean distances and tolerance limits provide a simple and statistically valid method to compare PCB congener patterns among groups. Published by Elsevier Ltd.

  5. PCB in the air during landfilling of a contaminated lake sediment

    NASA Astrophysics Data System (ADS)

    Bremle, G.; Larsson, P.

    We studied PCB concentration in the air during the build-up of a landfill of PCB-contaminated sediment. A small lake was remediated and the sediment (150 000 m 3 containing about 400 kg PCB) deposited in a nearby landfill. PCB concentration in the air was elevated during landfilling and the extent was determined by the amount of sediment handled and the temperature. The air was enriched in more volatile PCB congeners compared to the deposited sediment, suggesting volatilization as the major transport process in addition to particle transport. The PCB concentration in air showed an exponential decline with distance from the centre of the landfill, with a one order of magnitude decrease 350 m from the centre. At a distance of 850 m from the centre about 5% of the elevated PCB level remained, which was significantly higher when compared to the reference concentration (15 km from the landfill). The PCB congener pattern changed gradually from the landfill centre to the reference. After the landfill was closed and the contaminated, dewatered sediment covered by uncontaminated soil, PCB levels and pattern were similar to that of the reference.

  6. Laboratory study of PCB transport from primary sources to settled dust.

    PubMed

    Liu, Xiaoyu; Guo, Zhishi; Krebs, Kenneth A; Greenwell, Dale J; Roache, Nancy F; Stinson, Rayford A; Nardin, Joshua A; Pope, Robert H

    2016-04-01

    Dust is an important sink for indoor air pollutants, such as polychlorinated biphenyls (PCBs) that were used in building materials and products. In this study, two types of dust, house dust and Arizona Test Dust, were tested in a 30-m(3) stainless steel chamber with two types of panels. The PCB-containing panels were aluminum sheets coated with a PCB-spiked primer or caulk. The PCB-free panels were coated with the same materials but without PCBs. The dust evenly spread on each panel was collected at different times to determine its PCB content. The data from the PCB panels were used to evaluate the PCB migration from the source to the dust through direct contact, and the data from the PCB-free panels were used to evaluate the sorption of PCBs through the dust/air partition. Settled dust can adsorb PCBs from air. The sorption concentration was dependent on the congener concentration in the air and favored less volatile congeners. When the house dust was in direct contact with the PCB-containing panel, PCBs migrated into the dust at a much faster rate than the PCB transfer rate due to the dust/air partition. The dust/source partition was not significantly affected by the congener's volatility. For a given congener, the ratio between its concentration in the dust and in the source was used to estimate the dust/source partition coefficient. The estimated values ranged from 0.04 to 0.16. These values are indicative of the sink strength of the tested house dust being in the middle or lower-middle range. PMID:26849196

  7. Concentrations of polychlorinated biphenyl congeners in cultivated oysters (Crassostrea gigas) in western Taiwan.

    PubMed

    Fang, M D; Fang, H-T; Lee, C-L; Ko, F-C; Baker, J E

    2006-08-01

    Spatial and temporal variations of polychlorinated biphenyl (PCB) concentrations in cultivated oysters from five aquaculture areas along the western coast of Taiwan were investigated. Poor correlations between total PCB concentrations (ng/g dry weight [dw]) and physiologic parameters of oysters (shell length, width, thickness, and lipid content) were found. Total PCB concentrations ranged from 3.4 to 94 cng/g dw. The highest value was found in oysters from the Lu'ermen aquaculture area, which receives wastewater from a sodium hydroxide and pentachlorophenol factory. Furthermore, principal component analysis confirmed that the PCB congener pattern in this area was distinct from others and that two additional pollution sources might exist in the Tainan and Hsinchu areas. Oysters with PCB concentrations > 1 SD above the geometric mean were found mainly in Tainan (stations TN5 to TN9) with only one increased concentration in the Yunlin (station YL2) and Hsinchu (station HC4) aquaculture areas. Except for four confined stations, TN3 to TN6, where total PCB concentrations were higher (p = 0.028) in the warmer (May and July) than in the colder season (November and March), seasonal variation of total PCB concentrations in oysters was not significant. Geometric mean and geometric mean plus 1 SD of total PCB concentrations in this study are lower than those in South Korea and the United States (Mussel Watch). PMID:16583259

  8. ANALYSIS OF 209 CHLORINATED BIPHENYL CONGENERS USING COMPREHENSIVE TWO-DIMENSIONAL GAS CHROMATOGRAPHY-TIME-OF-FLIGHT MASS SPECTROMETRY IN THE 1-D MODE FOLLOWED BY THE 2-D MODE

    EPA Science Inventory

    Since the initial discovery of polychlorinated biphenyls (PCBs) in the environment, the detection and identification of certain PCB congeners using the traditional one dimensional (1-D) chromatographic technique has been very challenging, especially, separating the 46 isomeric pe...

  9. The Influence of Atmospheric Transport Regimes on Polychlorinated Biphenyl (PCB) Concentrations Measured at Zeppelin

    NASA Astrophysics Data System (ADS)

    Ubl, S.; Scheringer, M.; Hungerbuehler, K.

    2013-12-01

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) of exclusively anthropogenic origin. PCBs are toxic, bioaccumulative and have a great potential of long-range transport. PCBs have been banned globally under the Stockholm convention on POPs since 2004. We analysed times series of 21 PCB congeners ranging from PCB 18 to PCB 187 that have been measured at Zeppelin (Spitsbergen) since 1993. Although primary PCB emissions have been steadily reduced, a strong decreasing trend is not observed in the PCB concentrations in the Arctic. In order to investigate the influence of atmospheric transport on the PCB concentrations and to identify the potential source regions of the PCBs, we calculated footprints for the Zeppelin measurement site using the Lagrangian Particle Dispersion Model FLEXPART. Footprints can be interpreted as potential source regions where PCBs may have been picked up. Based on various statistical analyses of the footprints (cluster analysis, k-medoid, silhouette), we identified the prevailing transport regimes for Zeppelin which were represented by 5 different clusters. Cluster 1 and 3 belong to transport regimes with highest residence times over Europe (cluster 1) and North-America (cluster 3); both transport regimes dominantly occur from late fall to early spring. Clusters 2 and 4 represent air masses with surface contact predominantly over the Atlantic Ocean (cluster 2), only occurring during the summer months, and the Arctic Ocean (cluster 4) mainly observed in spring and autumn, but also in summer. Cluster 5 is representative of air originating from the Pacific ocean and eastern Asia; this transport regime occurs mainly in spring and fall. We grouped the PCB concentrations measured at Zeppelin according to the 5 different clusters and calculated the median for each cluster and PCB congener. The median for medium to heavier PCBs is highest for cluster 1 and 3, which represent transport regimes over the continent, suggesting that

  10. Leopard frog PCB levels and evaluation of EROD as a biomarker in Green Bay ecosystem

    SciTech Connect

    Huang, Y.W.; Karasov, W.H.; Patnode, K.P.

    1995-12-31

    The induction of mixed function oxidases has been shown to be a promising biomarker in many taxa of wildlife, though not yet tested for amphibians. The three hypotheses tested in this study were (1) activities of hepatic EROD of leopard frog (Rana pipiens) are induced following exposure to planar chlorinated PCBs, (2) tissue PCB residue levels of leopard frogs are positively correlated with their wetland sediment PCB levels, and (3) EROD activities are positively correlated with tissue PCB concentrations and sediment PCB. In the laboratory, EROD was increased 2--3 times seven days after i.p. injection with PCB 126 at doses {ge} 2.3 ppm (wet mass basis). Leopard frogs from seven sites along the Lower Fox River and Green Bay in 1994--1995 were assayed for hepatic EROD activities and total PCB levels in carcasses. Tissue PCB levels ranged from 3 to 152 ppb (including coplanar congeners) and were highest from sites with higher sediment PCB. EROD activity in frogs collected in August--September was not significantly correlated with frog body mass and was similar among sites with one exception. There was no significant correlation between EROD activity and tissue PCB concentration. This result was consistent with the fact that the frogs collected from the Green Bay ecosystem had relatively low PCB levels compared with what was required for induction in the laboratory. The authors conclude that EROD activity is not a sensitive biomarker of PCB exposure in leopard frogs in this ecosystem.

  11. Study of penetration behavior of PCB-DNAPL in a sand layer by a column experiment.

    PubMed

    Okuda, Nobuyasu; Shimizu, Takaaki; Muratani, Masaru; Terada, Akihiko; Hosomi, Masaaki

    2014-11-01

    To better understand the infiltration performances of high concentration PCB oils (KC-300 and KC-1000 polychlorinated biphenyl (PCB) mixtures), representative dense non-aqueous phase liquid (DNAPL), under both saturated and unsaturated conditions, we conducted experiments on a sand column filled with Toyoura Standard Sand. When PCB oil with the volume comparable to the total porosity in the column was supplied, the residual PCB concentrations under PCB-water conditions were 4.9×10(4)mgkg(-1) in KC-300 and 3.9×10(4)mgkg(-1) in KC-1000. Under PCB-air conditions, residual PCB concentrations were 6.0×10(4)mgkg(-1) and 2.4×10(5)mgkg(-1) in the upper and lower parts for KC-300 and 3.6×10(4)mgkg(-1) and 1.5×10(5)mgkg(-1) in those for KC-1000, respectively, while the rest of the PCBs were infiltrated. On the other hand, when a small amount of PCB oil with the volume far smaller than the total porosity in the column was supplied, the original PCBs were not transported via water permeation. However, lower-chlorinated PCB congeners-e.g., di- or tri-chlorinated biphenyls-preferentially dissolved and were infiltrated from the bottom of the column. These propensities on PCB oil infiltration can be explained in conjunction with the degree of PCB saturation in the sand column. PMID:25113184

  12. Polychlorinated Biphenyl (PCB) Bioaccumulation in Fish: A Look at Michigan's Upper Peninsula

    NASA Astrophysics Data System (ADS)

    Sokol, E. C.; Urban, N. R.; Perlinger, J. A.; Khan, T.; Friedman, C. L.

    2014-12-01

    Fish consumption is an important economic, social and cultural component of Michigan's UpperPeninsula, where safe fish consumption is threatened due to polychlorinated biphenyl (PCB)contamination. Despite its predominantly rural nature, the Upper Peninsula has a history of industrialPCB use. PCB congener concentrations in fish vary 50-fold in Upper Peninsula lakes. Several factors maycontribute to this high variability including local point sources, unique watershed and lakecharacteristics, and food web structure. It was hypothesized that the variability in congener distributionscould be used to identify factors controlling concentrations in fish, and then to use those factors topredict PCB contamination in fish from lakes that had not been monitored. Watershed and lakecharacteristics were acquired from several databases for 16 lakes sampled in the State's fishcontaminant survey. Species congener distributions were compared using Principal Component Analysis(PCA) to distinguish between lakes with local vs. regional, atmospheric sources; six lakes were predictedto have local sources and half of those have confirmed local PCB use. For lakes without local PCBsources, PCA indicated that lake size was the primary factor influencing PCB concentrations. The EPA'sbioaccumulation model, BASS, was used to predict PCB contamination in lakes without local sources as afunction of food web characteristics. The model was used to evaluate the hypothesis that deep,oligotrophic lakes have longer food webs and higher PCB concentrations in top predator fish. Based onthese findings, we will develop a mechanistic watershed-lake model to predict PCB concentrations infish as a function of atmospheric PCB concentrations, lake size, and trophic state. Future atmosphericconcentrations, predicted by modeling potential primary and secondary emission scenarios, will be usedto predict the time horizon for safe fish consumption.

  13. Fetal adrenal development: comparing effects of combined exposures to PCB 118 and PCB 153 in a sheep model.

    PubMed

    Zimmer, Karin E; Kraugerud, Marianne; Aleksandersen, Mona; Gutleb, Arno C; Østby, Gunn C; Dahl, Ellen; Berg, Vidar; Skaare, Janneche U; Olsaker, Ingrid; Ropstad, Erik

    2013-03-01

    This study investigated the effects of exposure to the ubiquitous contaminants polychlorinated biphenyls (PCBs) on the fetal adrenal cortex and on plasma cortisol using the domestic sheep (Ovis aries) as a model. Pregnant ewes were intendedly subjected to oral treatment with PCB 153 (98 μg/kg bw/day), PCB 118 (49 μg/kg bw/day) or the vehicle corn oil from mating until euthanasia on gestation day 134 (±0.25 SE). However, because of accidental cross-contamination occurring twice causing a mixed exposure scenario in all three groups, the focus of this paper is to compare three distinct groups of fetuses with different adipose tissue PCB levels (PCB 153high, PCB 118high and low, combined groups) rather than comparing animals exposed to single PCB congeners to those of a control group. When comparing endocrine and anatomical parameters from fetuses in the PCB 153high (n = 13) or PCB 118high (n = 14) groups with the low, combined group (n = 14), there was a significant decrease in fetal body weight (P < 0.05), plasma cortisol concentration (P < 0.001) and adrenal cortex thickness (P < 0.001). Furthermore, adrenal weight was decreased and plasma ACTH was increased only in the PCB 118high group. Expression of several genes encoding enzymes and receptors related to steroid hormone synthesis was also affected and mostly down-regulated in fetuses with high PCB tissue levels. In conclusion, we suggest that mono-and di-ortho PCBs were able to interfere with growth, adrenal development and cortisol production in the fetal sheep model. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013. PMID:21544918

  14. Evidence of elevated levels of polychlorinated biphenyl congeners in commonly consumed fish from Eleyele Reservoir, Southwestern Nigeria.

    PubMed

    Adeogun, Aina O; Adedara, Isaac A; Farombi, Ebenezer O

    2016-01-01

    Environmental pollution of water, which is a source of cheap and affordable protein in the form of fish on which the population depends on, is of great concern globally. The present study assesses the levels of polychlorinated biphenyls (PCBs) congeners in sediments and six commonly consumed cichlid species from Eleyele Reservoir, Southwestern Nigeria. The results indicate that the concentrations of heavier PCB congeners are higher than the lighter congeners in both sediment and fish tissue. The predominant PCB congeners in the sediment samples from this site were PCBs 8, 44, 114, 101, 189, 196, 206 and 209. The concentration of PCB congeners increased with increasing molecular weight from hepta-PCB to deca-PCB in all fish species. The trend in accumulation of total PCBs in fish was as follows: Tilapia guineensis (2,531.1 ± 74.6 ng/g) > Sarotherodon galilaeus (1178.7 ± 68.5 ng/g) > Oreochromis niloticus > (891.8 ± 49.6 ng/g) > Tilapia zillii (832.8 ± 38.2 ng/g) > Hemichromis fasciatus (475.7 ± 28.5 ng/g) > Sarotherodon melanotheron (333.2 ± 26.1 ng/g). In summary, data from this study shows that the levels of PCBs in cichlid species from Eleyele Reservoir are higher than the threshold level of 0.023-0.047 ng g(-1) recommended by United States Environmental Protection Agency. Such elevated PCB levels present significant health implications for human consumers and a threat to the resident fish communities. PMID:23859942

  15. Net trophic transfer efficiencies of polychlorinated biphenyl congeners to lake trout (Salvelinus namaycush) from its prey

    USGS Publications Warehouse

    Madenjian, Charles P.; David, Solomon R.; Rediske, Richard R.; O’Keefe, James P.

    2012-01-01

    Lake trout (Salvelinus namaycush) were fed bloater (Coregonus hoyi) in eight laboratory tanks over a 135-d experiment. At the start of the experiment, four to nine fish in each tank were sacrificed, and the concentrations of 75 polychlorinated biphenyl (PCB) congeners within these fish were determined. Polychlorinated biphenyl congener concentrations were also determined in the 10 lake trout remaining in each of the eight tanks at the end of the experiment as well as in the bloater fed to the lake trout. Each lake trout was weighed at the start and the end of the experiment, and the amount of food eaten by the lake trout was recorded. Using these measurements, net trophic transfer efficiency (γ) from the bloater to the lake trout in each of the eight tanks was calculated for each of the 75 congeners. Results showed that γ did not vary significantly with the degree of chlorination of the PCB congeners, and γ averaged 0.66 across all congeners. However,γ did show a slight, but significant, decrease as logKOW increased from 6.0 to 8.2. Activity level of the lake trout did not have a significant effect on γ.

  16. Cytochrome c adducts with PCB quinoid metabolites.

    PubMed

    Li, Miao; Teesch, Lynn M; Murry, Daryl J; Pope, R Marshal; Li, Yalan; Robertson, Larry W; Ludewig, Gabriele

    2016-02-01

    Polychlorinated biphenyls (PCBs) are a group of 209 individual congeners widely used as industrial chemicals. PCBs are found as by-products in dye and paint manufacture and are legacy, ubiquitous, and persistent as human and environmental contaminants. PCBs with fewer chlorine atoms may be metabolized to hydroxy- and dihydroxy-metabolites and further oxidized to quinoid metabolites both in vitro and in vivo. Specifically, quinoid metabolites may form adducts on nucleophilic sites within cells. We hypothesized that the PCB-quinones covalently bind to cytochrome c and, thereby, cause defects in the function of cytochrome c. In this study, synthetic PCB quinones, 2-(4'-chlorophenyl)-1,4-benzoquinone (PCB3-pQ), 4-4'-chlorophenyl)-1,2-benzoquinone (PCB3-oQ), 2-(3', 5'-dichlorophenyl)-1,4-benzoquinone, 2-(3',4', 5'-trichlorophenyl)-1,4-benzoquinone, and 2-(4'-chlorophenyl)-3,6-dichloro-1,4-benzoquinone, were incubated with cytochrome c, and adducts were detected by liquid chromatography-mass spectrometry (LC-MS) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI TOF). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was employed to separate the adducted proteins, while trypsin digestion and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were applied to identify the amino acid binding sites on cytochrome c. Conformation change of cytochrome c after binding with PCB3-pQ was investigated by SYBYL-X simulation and cytochrome c function was examined. We found that more than one molecule of PCB-quinone may bind to one molecule of cytochrome c. Lysine and glutamic acid were identified as the predominant binding sites. Software simulation showed conformation changes of adducted cytochrome c. Additionally, cross-linking of cytochrome c was observed on the SDS-PAGE gel. Cytochrome c was found to lose its function as electron acceptor after incubation with PCB quinones. These data provide evidence that the covalent

  17. Comparative developmental toxicity of planar polychlorinated biphenyl congeners in chickens, American kestrels, and common terns

    SciTech Connect

    Hoffman, D.J.; Melancon, M.J.; Klein, P.N.; Eisemann, J.D.; Spann, J.W.

    1998-04-01

    The effects of polychlorinated biphenyl (PCB) congeners, PCB 126 (3,3{prime},4,4{prime},5-pentaCB) and PCB 77 (3,3{prime},4,4{prime}-tetraCB), were examined in chicken (Gallus gallus), American kestrel (Falco sparverius), and common tern (Sterna hirundo) embryos through hatching, following air cell injections on day 4. PCB 126 caused malformations and edema in chickens starting at 0.3 ppb, in kestrels at 2.3 to 23 ppb, but in terns only at levels affecting hatching success (44 ppb). Extent of edema was most severe in chickens and least in terns. Defects of the beak were common in all species but with crossed beak most prevalent in terns. Effects on embryo growth were most apparent for PCB 126 in chickens and kestrels. The approximate 50% lethal dose (LD50) for PCB 126 in chickens was 0.4 ppb, in kestrels was 65 ppb, and in terns was 104 ppb. The approximate LD50 for PCB 77 in chickens was 2.6 ppb and in kestrels was 316 ppb. Induction of cytochrome P450 associated monooxygenase activity (ethoxyresorufin-O-dealkylase activity) by PCB 126 in chick embryo liver was about 800 times more responsive than in tern and at least 1,000 times more responsive than in kestrel. High concentrations of PCB 126 found in bald eagle eggs are nearly 20-fold higher than the lowest toxic concentration tested in kestrels. Concentrations of PCB 126 causing low-level toxic effects in common tern eggs are comparable to highest levels in common terns and Forster`s terns in the field, suggesting additional involvement of other compounds in the Great Lakes.

  18. Comparative developmental toxicity of planar polychlorinated biphenyl congeners in chickens, American kestrels, and common terns

    USGS Publications Warehouse

    Hoffman, D.J.; Melancon, M.J.; Klein, P.N.; Eisemann, J.D.; Spann, J.W.

    1998-01-01

    The effects of PCB congeners, PCB 126 (3,3',4,4',5-pentaCB) and PCB 77 (3,3'4,4'-tetraCB), were examined in chicken (Gallus gallus), American kestrel (Falco sparverius), and common tern (Sterna hirundo) embryos through hatching, following air cell injections on day 4. PCB 126 caused malformations and edema in chickens starting at 0.3 ppb, in kestrels at 2.3 ppb, but in terns only at levels affecting hatching success (44 ppb). Extent of edema was most severe in chickens and least in terns. Defects of the beak were common in all species, but with crossed beak most prevalent in terns. Effects on embryo growth were most apparent for PCB 126 in chickens and kestrels. The approximate LD50 for PCB 126 in chickens was 0.4 ppb, in kestrels was 65 ppb, and in terns was 104 ppb. The approximate LD50 for PCB 77 in chickens was 2.6 ppb and in kestrels was 316 ppb. Induction of cytochrome P450 associated monooxygenase activity (EROD activity) by PCB 126 in chick embryo liver was about 800 times more responsive than in tern and at least 1000 times more responsive than in kestrel. High concentrations of PCB 126 found in bald eagle eggs are nearly 20-fold higher than the lowest toxic concentration tested in kestrels. Concentrations of PCB 126 causing low level toxic effects in common tern eggs are comparable to highest levels in common terns and Forster's terns in the field, suggesting additional involvement of other compounds in the Great Lakes.

  19. Electrical Stimulation of Microbial PCB Degradation in Sediment

    PubMed Central

    Chun, Chan Lan; Payne, Rayford B.; Sowers, Kevin R.; May, Harold D.

    2012-01-01

    Bioremediation of polychlorinated biphenyls (PCBs) has been precluded in part by the lack of a cost-effective method to stimulate microbial degradation in situ. A common limitation is the lack of an effective method of providing electron donors and acceptors to promote in situ PCB biodegradation. Application of an electric potential to soil/sediment could be an effective means of providing electron-donors/-acceptors to PCB dechlorinating and degrading microorganisms. In this study, electrical stimulation of microbial PCB dechlorination/ degradation was examined in sediment maintained under simulated in situ conditions. Voltage was applied to open microcosms filled with PCB-impacted (Aroclor 1242) freshwater sediment from a Superfund site (Fox River, WI). The effect of applied low voltages (1.5 to 3.0V) on the microbial transformation of PCBs was determined with: 1) spiked PCBs, and 2) indigenous weathered PCBs. The results indicate that both oxidative and reductive microbial transformation of the spiked PCBs was stimulated but oxidation was dominant and most effective with higher voltage. Chlorobenzoates were produced as oxidation metabolites of the spiked PCBs, but increasing voltage enhanced chlorobenzoate consumption, indicating that overall degradation was enhanced. In the case of weathered PCBs, the total concentration decreased 40–60% in microcosms exposed to electric current while no significant decrease of PCB concentration was observed in control reactors (0 V or sterilized). Single congener analysis of the weathered PCBs showed significant loss of di- to penta-chlorinated congeners, indicating that microbial activity was not limited to anaerobic dechlorination of only higher chlorinated congeners. Degradation was most apparent with the application of only 1.5 V where anodic O2 was not generated, indicating a mechanism of degradation independent of electrolytic O2. Low voltage stimulation of the microbial degradation of weathered PCBs observed in this

  20. TISSUE DISTRIBUTION OF PCBS AND ORGANOCHLORINE PESTICIDES IN ALASKAN NORTHERN FUR SEALS: COMPARISON OF VARIOUS CONGENER CLASSIFICATION SCHEMES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) are believed to adversely affect reproduction and cause health problems in Pinnipeds 1-4. In this study, 145 PCB congeners and OCPs were analyzed in 10 juvenile male northern fur seals, Callorhinus ursinus, collected from Alaskan...

  1. RELATIVE POTENCY VALUES FOR POLYCHLORINATED DIBENZO-P-DIOXIN, DIBENZOFURAN AND BIPHENYL CONGENERS TO INDUCE CYTOCHROME P4501A MRNA IN A ZEBRAFISH LIVER CELL LINE (ZF-L)

    EPA Science Inventory

    Induction of cytochrome P450 (CYPIA) mRNA by polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF) and polychlorinated biphenyl (PCB) congeners was measured in a zebrafish liver cell line (ZF-L). ZF-L cells were far less sensitive to PCDD, PCDF and PCB cong...

  2. A reassessment of the nomenclature of polychlorinated biphenyl (PCB) metabolites.

    PubMed Central

    Maervoet, Johan; Covaci, Adrian; Schepens, Paul; Sandau, Courtney D; Letcher, Robert J

    2004-01-01

    Polychlorinated biphenyls (PCBs) are a widespread class of persistent organic chemicals that accumulate in the environment and humans and are associated with a broad spectrum of health effects. PCB biotransformation has been shown to lead to two classes of PCB metabolites that are present as contaminant residues in the tissues of selected biota: hydroxylated (HO) and methyl sulfone (MeSO2) PCBs. Although these two types of metabolites are related structures, different rules for abbreviation of both classes have emerged. It is important that a standardized nomenclature for the notation of PCB metabolites be universally agreed upon. We suggest that the full chemical name of the PCB metabolite and a shorthand notation should be adopted using the International Union of Pure and Applied Chemistry's chemical name/original Ballschmiter and Zell number of the parent congener, followed by the assignment of the phenyl ring position number of the MeSO2- or HO-substituent. This nomenclature provides a clear, unequivocal set of rules in naming and abbreviating the PCB metabolite structure. Furthermore, this unified PCB metabolite nomenclature approach can be extended to the naming and abbreviation of potential metabolites of structurally analogous contaminants such as HO-polybrominated biphenyls and HO-polybrominated diphenyl ethers. PMID:14998742

  3. Lipid and PCB compositions in water-striders from contaminated streams

    SciTech Connect

    Napolitano, G.E.; Richmond, J.E.; Klasson, K.T.; Hill, W.R.

    1995-12-31

    In a study of hydrophobic substances in stream surface-waters, the authors investigated lipids and polychlorinated biphenyls (PCBs) of water-striders (Gerris remiges). Lipid class, fatty acid, and PCB congener compositions were analyzed in insects from four streams located downstream of the Department of Energy`s facilities near the city of Oak Ridge, Tennessee. Total lipid contents of water-striders varied seasonally, showing maximum concentrations in summer and fall ({approximately} 9.0% of wet weight), and minimum concentrations in winter and spring. Total PCB concentrations of water-striders varied between streams and appeared to parallel PCB concentrations reported for the aquatic fauna of each site. Fatty acids were used as chemical markers to detect differences in the food resources of water-striders. The triacylglycerol fatty acid composition was remarkably similar in all the streams and reflected to a large extent, that of a terrestrial insect. The PCB congener composition of water-striders varied significantly between streams, showing a relative enrichment of the less chlorinated congeners in the less contaminated samples. There was also a positive correlation between PCB burden and average molecular weights. Differences between the chlorine content of the dominant congeners suggest distinct sources of PCBs for the different streams. The apparent similarities in the food resources of the water-striders, as inferred from fatty acid markers, and their distinct PCB congener composition, suggest absorption or ingestion from the surface micro-layer, rather than diet, as a more likely route of uptake of lipophilic contaminants by water-striders.

  4. PCB storage requirements

    SciTech Connect

    1994-12-01

    Polychlorinated biphenyls (PCBs) are a class of organic chemicals that had become widely used in industrial applications due to their practical physical and chemical properties. Historical uses of PCBs include dielectric fluids (used in utility transformers, capacitors, etc.), hydraulic fluids, and other applications requiring stable, fire-retardant materials. Due to findings that PCBs may cause adverse health effects and due to their persistence and accumulation in the environment, the Toxic Substances Control Act (TSCA), enacted on october 11, 1976, banned the manufacture of PCBs after 1978 [Section 6(e)]. The first PCB regulations, promulgated at 40 CFR Part 761, were finalized on February 17, 1978. These PCB regulations include requirements specifying disposal methods and marking (labeling) procedures, and controlling PCB use. To assist the Department of Energy (DOE) in its efforts to comply with the TSCA statute and implementing regulations, the Office of Environmental Guidance has prepared the document ``Guidance on the Management of Polychlorinated Biphenyls (PCBs).`` That document explains the requirements specified in the statute and regulations for managing PCBs, including PCB use, storage, transport, and disposal. The requirements specified at 40 CFR Part 761.65 require most PCB wastes to be stored in a facility that meets the specifications of that section. Additionally, the regulations include rules concerning time limits for PCBs and PCB Items in storage, rules concerning leaking electrical equipment, and rules concerning types of containers used to store PCBs and PCB Items. This Information Brief supplements the PCB guidance document by responding to common questions concerning storage requirements for PCBs. It is one of a series of Information Briefs pertinent to PCB management issues.

  5. Potentially estrogenic polychlorinated biphenyls congeners serum levels and its relation with lung cancer.

    PubMed

    Recio-Vega, Rogelio; Mendez-Henandez, Alejandra; Gabriel, Antonio Padua Y; Jacobo-Avila, Antonio; Portales-Castanedo, Arnulfo; Hernandez-Gonzalez, Sandra; Gallegos-Arreola, Martha Patricia; Ocampo-Gomez, Guadalupe

    2013-09-01

    Lung cancer is the most common cancer in the world. The main cause of lung cancer is cigarette smoke; however, other important genetic and environmental risk factors play a significant role in the development of lung cancer. Among these factors, occupational and accidental exposure to polychlorinated biphenyls (PCBs) has been associated with an increased risk in lung cancer, suggesting that PCBs could be potent carcinogens. The aim of the present study was to investigate the association between PCB exposure levels, CYP1A1 polymorphisms and the risk of lung cancer. This study enrolled newly diagnosed lung cancer patients. Environmental and occupational information related to the patients studied was collected. Blood samples were taken for the measurement of serum levels of 20 PCB congeners and for CYP1A1 polymorphism analysis. The serum levels of two PCB congeners with potential estrogenic activity were higher in lung cancer patients. The risk of lung cancer was found to correlate with age, gender, smoking history and with agricultural workers, as well as with congener 18. No differences were found in the frequency of CYP1A1 polymorphisms. Furthermore, we did not find a correlation between CYP1A1 polymorphisms and PCB serum levels. The high levels of PCB with estrogenic activity found in our cases, could promote lung cancer inducing cell proliferation in non-neoplastic and neoplastic lung cells via ERβ; inducing the formation of DNA adducts, producing oxidative stress with the subsequent DNA damage and increasing the endogenous catechol levels by catechol-O-methyl transferase (COMT) inhibition. PMID:22729568

  6. The shy prefer familiar congeners.

    PubMed

    Benhaïm, David; Ferrari, Sébastien; Chatain, Béatrice; Bégout, Marie-Laure

    2016-05-01

    The shy-bold continuum is both a fundamental aspect of human behavior and a relatively stable behavioral trait for many other species. Here we assessed whether shy individuals prefer familiar congeners, taking the European sea bass, a recently domesticated fish showing similar behavioral responses to wild fish, as a model to better understand the inter-individual variability in social behavior previously observed in this species. In the wild, the link between familiarity i.e., the preference of fish for familiar congeners and boldness could be part of the mechanism underlying shoaling formation in fish. Thirty fish were individually tested in a device designed to assess the preference for a familiar vs. an unfamiliar congener on the basis of visual cues only. An open field test (OFT) with shelter was performed on the same fish 32 days later to assess the boldness of each individual. Variables of interest included the proportion of time spent in the shelter, border and center zone of the arena and variables of activity. Variables measured in OFT were collapsed into first principal component scores using Principal Components Analysis (PCA) which allowed characterizing a shy-bold continuum. Time spent near the familiar congener was negatively correlated with boldness i.e., shy individuals spent most of the time near the familiar congener. We discuss the relevance of these findings to the understanding of the behavior of European sea bass and suggest that the link between familiarity and shyness is a general aspect of both animal and human behavior. PMID:26995491

  7. Effects of PCB contamination on the reproduction of the DAB Limanda limanda L. under laboratory conditions

    NASA Astrophysics Data System (ADS)

    Fonds, Mark; Casal, Elizabeth; Schweizer, Dominik; Boon, Jan P.; Van der Veer, Henk W.

    The effect of PCB contamination on the reproduction of female dab was studied under laboratory conditions. Females were contaminated during gonad maturation by multiple oral administration of capsules containing the technical PCB mixture Clophen A40. PCB contamination resulted in increased levels in the eggs, with concentrations of selected PCB congeners of 35 to 86 μg·g -1 lipid for PCB-exposed fish, 10 μg·g -1 lipid for eggs from fish fed with mussel meat and fish fed with shrimp. A statistically significant dose-effect relationship was found between the PCB content of the eggs and the PCB dose ingested by the fish. For eggs from the PCB-treated fish the mean fertilization rate was 61% and mean hatching 45%, compared to 67% fertilization and 59% hatching for eggs from untreated fish. Rate of development and survival of the eggs and mortality of the larvae after hatching were mainly related to incubation temperature. No statistically significant differences between untreated and PCB-treated fish could be found in egg production, egg quality, fertilization rate, hatching rate and survival of larvae.

  8. Uptake and depuration of PCB-153 in edible shrimp Palaemonetes varians and human health risk assessment.

    PubMed

    Grilo, T F; Cardoso, P G; Pato, P; Duarte, A C; Pardal, M A

    2014-03-01

    A medium-term mesocosm exposure study was conducted to elucidate bioaccumulation and depuration of polychlorinated biphenyl congener 153 (PCB-153) in edible shrimp Palaemonetes varians. Over the 15-day exposure period, shrimp under different exposure concentrations exhibited a significant increase in PCB-153 concentration compared with control organisms. Distinct bioaccumulation patterns and uptake rates were observed depending on the exposure concentrations. For low PCB-153 exposure levels (0.25μgL(-1)), accumulation followed a saturation model, reaching an apparent steady state after fifteen days exposure. For intermediate (2.5μgL(-1)) and high PCB-153 levels (25μgL(-1)), accumulation was faster and linear. In addition, the bioaccumulation rate was not proportional to PCB-153 concentration, and the bioaccumulation was higher at intermediate exposure concentrations. Regarding the depuration phase, P. varians lost up to 30% of PCB-153 after 72h and levels continued slowly to decrease until the end of the 30-d experimental period. However, PCB-153 levels in shrimp did not reach background values, and those exposed to moderate and high PCB-153 concentrations presented contamination levels much higher than the regulatory limit for human food consumption (75ngg(-1) ww for Σ6 PCB). PMID:24507133

  9. Polychlorinated biphenyl congeners in sediment cores from the Upper Mississippi River.

    PubMed

    Martinez, Andres; Schnoebelen, Douglas J; Hornbuckle, Keri C

    2016-02-01

    We determined polychlorinated biphenyls (PCBs) and radionuclide (137)Cs in sediment cores from the Upper Mississippi River (UMR) and the Iowa River, Iowa, at their confluence. Vertical distribution of (137)Cs indicated negligible mixing in the UMR core, while the Iowa River core showed signs of mixing. A clear (137)Cs peak was found in the UMR core, which was correlated to 1963. The PCB vertical distribution in UMR core was similar to the historical trend in Aroclor production observed in Great Lakes cores, with a peak close to the (137)Cs peak, suggesting a date near 1960. In general, PCB congener profiles in both cores resembled the Iowa soil background signal. We concluded that despite evidence of mixing in the Iowa River core, both cores retain the PCB signature of historical and regional environmental exposure. Further, our results indicate that this iconic waterway has a long history of PCBs that reflects national production and use. PMID:26547030

  10. Phytoremediation of polychlorinated biphenyl (PCB)-contaminated sediment: a greenhouse feasibility study.

    PubMed

    Smith, K E; Schwab, A P; Banks, M K

    2007-01-01

    Contaminated sediments dredged from navigable waterways often are placed in confined disposal facilities to prevent further spread of the pollutants. Reducing contaminants to acceptable levels would allow for disposal of the sediments and further dredging activity. A greenhouse study was conducted to evaluate plant treatments and the addition of an organic amendment to decrease the concentration of PCB congeners found in Arochlor 1260. Sediment treated with the amendment and either low transpiring plants or no plants had the greatest removal of the PCB congeners. High-transpiring plants apparently prevented the highly reducing conditions required for reductive dechlorination of highly chlorinated PCBs. Most likely, the amendment provided labile carbon that initiated the reducing conditions needed for dechlorination. The sediment moisture content and moisture-related plant parameters were significant predictors of the PCB loss. Carex aquatalis and Spartina pectinata are predicted to be the most effective plant treatments for phytoremediation of PCBs. PMID:17215232

  11. Toxic potential of non-ortho and mono-ortho coplanar PCBs in commercial PCB preparations: 2,3,7,8-T/sub 4/ CDD Toxicity Equivalence Factors Approach

    SciTech Connect

    Kannan, N.; Tanabe, S.; Tatsukawa, R.

    1988-08-01

    Identification of highly toxic polychlorinated dibenzofurans (PCDFs) in commercial PCBs has contributed to the belief that they play a major role in the PCB toxicity. However, Quantitative Structure Activity Relationship (QSAR) studies have indicated that PCB congeners with chlorine substitution at both para and two or more meta positions resemble 2,3,7,8-tetrachlorodibenzo-p-dioxin (T/sub 4/CDD) in their biologic and toxic effects due to their coplanarity. The relative toxic potential of these PCB isomers in wild animals such as Forster's tern, marine mammals and Snapping turtle has been emphasized. Some members of these toxic congeners were also identified and quantitated in commercial PCBs. However, there is no serious effort to evaluate the toxic potential of these PCB congeners in commercial PCB mixtures. Hence an isomer-specific toxic evaluation was attempted in those mixtures to understand the chemical factors behind their toxicity.

  12. Determination of Atmospheric PCB Level Variations in Continuously Collected Samples.

    PubMed

    Sakin, Ahmet Egemen; Tasdemir, Yücel

    2016-08-01

    Polychlorinated biphenyls (PCBs) were measured in ambient air samples (n = 48) that were collected for a 2- to 3-day period in each season (winter, spring, summer, fall) of 2013. The samples were collected on the Campus of Uludag University, which is in a semirural region. The samples were collected using a high-volume air sampler. The gas and particle phase concentrations of 87 PCB congeners (Σ87PCB) were measured in these samples. The average gas and particle phase concentrations of the Σ87PCB were calculated to be 293 ± 257 and 52 ± 56 ng/m(3), respectively. However, the results of short-term measurements showed that the variation among the measurements in the gas phase was up to 39-fold and up to 84-fold in the particle phase. These results demonstrated that the ambient air PCB concentrations were not stable and changed dramatically on a daily basis. Therefore, it was clear that a small number of samples could not be representative of the entire region. Furthermore, the obtained concentrations showed differences that depended on the meteorological conditions and long distance transportation. The sampling indicated that PCB homologues with 3 or 4 chlorines were dominant. PMID:27290669

  13. PCB recordkeeping and reporting

    SciTech Connect

    1994-12-01

    Polychlorinated biphenyls (PCBs) are a class of organic chemicals that had become widely used in industrial applications due to their practical physical and chemical properties. Historical uses of PCBs include dielectric fluids (used in utility transformers, capacitors, etc.), hydraulic fluids, and other applications requiring stable, fire-retardant materials. Due to findings that PCBs may cause adverse health effects and due to their persistence and accumulation in the environment, the Toxic Substances Control Act (TSCA), enacted on October 11, 1976, banned the manufacture of PCBs after 1978 [Section 6(e)]. The first PCB regulations, promulgated at 40 CFR Part 761, were finalized on February 17, 1978. These PCB regulations include requirements specifying disposal methods and marking (labeling) procedures, and controlling PCB use. To assist the Department of Energy (DOE) in its efforts to comply with the TSCA statute and implementing regulations, the Office of Environmental Guidance has prepared the document ``Guidance on the Management of Polychlorinated Biphenyls (PCBs).`` That document explains the requirements specified in the statute and regulations for managing PCBs including PCB use, storage, transport, and disposal. All generators, disposers, and storers of PCB waste must comply with the recordkeeping and reporting requirements found at 40 CFR 761.180. The regulations include directions for writing and maintaining annual records and annual document logs and for preparing annual reports, exception reports, manifest discrepancy reports, and unmanifested waste reports. This Information Brief supplements the PCB guidance document by responding to common questions concerning recordkeeping and reporting requirements for PCBs. It is one of a series of Information Briefs pertinent to PCB management issues.

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

    PubMed

    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). PMID:24380619

  15. Empirical modeling of an in vitro activity of polychlorinated biphenyl congeners and mixtures.

    PubMed Central

    Svendsgaard, D J; Ward, T R; Tilson, H A; Kodavanti, P R

    1997-01-01

    The goal of this research is to predict an in vitro activity of polychlorinated biphenyl (PCB) congeners and their mixtures and to describe the relationship between this activity and chemical structure. The test system used multiple PCB concentrations on each cell culture plate in a repeated measures design, which improved precision for comparing between concentration levels. A weighted regression that accounted for this experimental design feature was used in fitting a nonlinear dose-response exponential model to the PCB concentration-activity data from an in vitro test system in which 3H-phorbol ester binding was measured in cerebellar granule cells exposed to different PCB congeners to test for their effects on protein kinase C translocation. The model allowed for the minimum level to be less than control, a common slope, and the estimation of the log of the concentration that produces an activity 50% above the control activity (E50) for 36 congeners and 3 commercial mixtures. Next, a weighted logistic regression using a second order response model in the variables Clortho, Clpara, and Clmeta was used to relate the estimated log E50s to indicators of chemical structure. This model was preferred over models that might seem more mechanistically based because in internal validation, it attained a smaller PRESS statistic (the sum of squares between all observed and predicted observations) than other models. Evidently, this second order model makes more efficient use of parameters than other models considered. Plots of the predictions of the logistic second order response model versus log Kow confirm the usual pattern that congeners with intermediate levels of log Kow are the more active. The data of three commercial mixtures were included in this regression by assuming a common combination index (ratio of observed E50 to predicted E50, assuming dose addition). The logistic model suggests that congeners with one, two, or three chlorine substitutions at the ortho

  16. Cell death mechanisms in GT1-7 GnRH cells exposed to polychlorinated biphenyls PCB74, PCB118, and PCB153

    SciTech Connect

    Dickerson, Sarah M.; Guevara, Esperanza; Woller, Michael J.; Gore, Andrea C.

    2009-06-01

    Exposure to endocrine disrupting chemicals (EDCs) such as polychlorinated biphenyls (PCBs) causes functional deficits in neuroendocrine systems. We used an immortalized hypothalamic GT1-7 cell line, which synthesizes the neuroendocrine peptide gonadotropin-releasing hormone (GnRH), to examine the neurotoxic and endocrine disrupting effects of PCBs and their mechanisms of action. Cells were treated for 1, 4, 8, or 24 h with a range of doses of a representative PCB from each of three classes: coplanar (2,4,4',5-tetrachlorobiphenyl: PCB74), dioxin-like coplanar (2',3,4,4',5' pentachlorobiphenyl: PCB118), non-coplanar (2,2',4,4',5,5'-hexachlorobiphenyl: PCB153), or their combination. GnRH peptide concentrations, cell viability, apoptotic and necrotic cell death, and caspase activation were quantified. In general, GnRH peptide levels were suppressed by high doses and longer durations of PCBs, and elevated at low doses and shorter timepoints. The suppression of GnRH peptide levels was partially reversed in cultures co-treated with the estrogen receptor antagonist ICI 182,780. All PCBs reduced viability and increased both apoptotic and necrotic cell death. Although the effects for the three classes of PCBs were often similar, subtle differences in responses, together with evidence that the combination of PCBs acted slightly different from individual PCBs, suggest that the three tested PCB compounds may act via slightly different or more than one mechanism. These results provide evidence that PCB congeners have endocrine disrupting and/or neurotoxic effects on the hypothalamic GnRH cell line, a finding that has implications for environmental endocrine disruption in animals.

  17. Proceedings: 1981 PCB seminar

    SciTech Connect

    Addis, G.; Marks, J.

    1982-09-01

    The EPRI PCB seminar, held in Dallas, Texas, on December 1 to 3, 1981, was the first comprehensive seminar covering PCB problems and solutions of interest to the electric utilities. The purpose of the meeting, attended by 300 participants, was to present emerging technologies and ideas for PCB analysis and removal. The major areas covered were: background and history of the problem, analytic techniques, spill cleanup, destruction of askarels, treatment of capacitors, and decontamination of oil. Both EPRI-sponsored and independently developed projects are included. In addition to the ongoing research on new technologies, some presentations cover processes ready or almost ready for commercialization. Supplementing the proceedings, a videotape of author interviews was prepared and is available for purchase from EPRI (415/855-2286).

  18. Microbial community analysis of switchgrass planted and unplanted soil microcosms displaying PCB dechlorination

    PubMed Central

    Liang, Yi; Meggo, Richard; Hu, Dingfei; Schnoor, Jerald L.; Mattes, Timothy E.

    2015-01-01

    Polychlorinated biphenyls (PCBs) pose potential risks to human and environmental health because they are carcinogenic, persistent and bioaccumulative. In this study we investigated bacterial communities in soil microcosms spiked with PCB 52, 77 and 153. Switchgrass (Panicum virgatum) was employed to improve overall PCB removal and redox cycling (i.e. sequential periods of flooding followed by periods of no flooding) was performed in an effort to promote PCB dechlorination. Lesser chlorinated PCB transformation products were detected in all microcosms, indicating the occurrence of PCB dechlorination. Terminal restriction fragment length polymorphism (T-RFLP) and clone library analysis showed that PCB spiking, switchgrass planting and redox cycling affected the microbial community structure. Putative organohalide-respiring Chloroflexi populations, which were not found in unflooded microcosms, were enriched after two weeks of flooding in the redox-cycled microcosms. Sequences classified as Geobacter sp. were detected in all microcosms, and were most abundant in the switchgrass-planted microcosm spiked with PCB congeners. The presence of possible organohalide-respiring bacteria in these soil microcosms suggests they play a role in PCB dechlorination therein. PMID:25820643

  19. PCB 77 dechlorination products modulate pro-inflammatory events in vascular endothelial cells

    PubMed Central

    Eske, Katryn; Newsome, Bradley; Han, Sung Gu; Murphy, Margaret; Bhattacharyya, Dibakar

    2013-01-01

    Persistent organic pollutants such as polychlorinated biphenyls (PCBs) are associated with detrimental health outcomes including cardiovascular diseases. Remediation of these compounds is a critical component of environmental policy. Although remediation efforts aim to completely remove toxicants, little is known about the effects of potential remediation byproducts. We previously published that Fe/Pd nanoparticles effectively dechlorinate PCB 77 to biphenyl, thus eliminating PCB-induced endothelial dysfunction using primary vascular endothelial cells. Herein, we analyzed the toxic effects of PCB congener mixtures (representative mixtures of commercial PCBs based on previous dechlorination data) produced at multiple time points during the dechlorination of PCB 77 to biphenyl. Compared with pure PCB 77, exposing endothelial cells to lower chlorinated PCB byproducts led to improved cellular viability, decreased superoxide production, and decreased nuclear factor kappa B activation based on duration of remediation. Presence of the parent compound, PCB 77, led to significant increases in mRNA and protein inflammatory marker expression. These data implicate that PCB dechlorination reduces biological toxicity to vascular endothelial cells. PMID:23504249

  20. Tissue Distribution of Polychlorinated Biphenyls and Organochlorine Pesticides and Potential Toxicity to Alaskan Northern Fur Seals Assessed Using PCBs Congener Specific Mode of Action Schemes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concentrations of 145 polychlorinated biphenyl (PCB) congeners were measured using gas chromatography-ion trap mass spectrometry in 8 different tissues (blubber, brain, heart, kidney, liver, lung, muscle, and reproductive tissues) of 10 Alaskan northern fur seals. The mean concentrations of bot...

  1. INCREASED [3H]-PHORBOL ESTER BINDING IN RAT CEREBELLAR GRANULE CELLS BY POLYCHLORINATED BIPHENYL MIXTURES AND CONGENERS: STRUCTURE-ACTIVITY RELATIONSHIPS

    EPA Science Inventory

    Our previous reports indicate that the neuroactivity of polychlorinated biphenyl (PCB) congeners may be associated with perturbations in cellular Ca2-homeostasis, and protein kinase C (PKC) activation/translocation. e have now studied the structure-activity relationship of severa...

  2. Evaluation of Comprehensive 2-D Gas Chromatography-Time-Of-Flight Mass Spectrometry for 209 Chlorinated Biphenyl Congeners in Two Chromatographic Runs

    EPA Science Inventory

    This research evaluates a recently developed comprehensive 2-D GC coupled with a time-of-flight (TOF) mass spectrometer for the potential separation of 209 PCB congeners, using a sequence of 1-D and 2-D chromatographic modes. In two consecutive chromatographic runs, using a 40 m,...

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

    PubMed

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

    2008-06-01

    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 the 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 1260 before and after incubation with microorganisms eluted from PCB-contaminated sediment of the Hudson River. Incubation with microorganisms resulted in a partially dechlorinated mixture (HR1260) dominated by ortho-substituted PCBs with four or fewer chlorines per biphenyl. Aroclor 1260 that had not been incubated with microorganisms had no significant effect on contraction frequency of rat uterine strips (gestation day 10) in vitro, whereas HR1260 dramatically increased contraction frequency to 718+/-134% of the basal rate at a total PCB concentration of 70 microM (p<0.05). The microbial dechlorination increased 2,2',4,4'-tetrachlorobiphenyl and one or more of four congeners that co-eluted during chromatography (2,3,3',5-tetrachlorobiphenyl, 2,3',4,5-tetrachlorobiphenyl, 2,2',4,4',6-pentachlorobiphenyl and 2,2',4,5',6-pentachlorobiphenyl) to 24 and 8 mol%, respectively. However, the uterotonic activities of the latter congeners were modest when evaluated either solely or in a reconstituted mixture and could not fully account for the uterotonic activity of HR1260. Nonetheless, the relative abundance of congeners with three or fewer chlorines increased to 14 mol% as a group in HR1260, suggesting that these congeners collectively contribute to the uterotonic activity even though the abundance of any one congener in this group was less than 5 mol%. PMID:18359014

  4. Indirect Evidence Link PCB Dehalogenation with Geobacteraceae in Anaerobic Sediment-Free Microcosms

    PubMed Central

    Praveckova, Martina; Brennerova, Maria V.; Holliger, Christof; De Alencastro, Felippe; Rossi, Pierre

    2016-01-01

    Although polychlorinated biphenyls (PCBs) production was brought to a halt 30 years ago, recalcitrance to degradation makes them a major environmental pollutant at a global scale. Previous studies confirmed that organohalide-respiring bacteria (OHRB) were capable of utilizing chlorinated congeners as electron acceptor. OHRB belonging to the Phyla Chloroflexi and Firmicutes are nowadays considered as the main PCB-dechlorinating organisms. In this study, we aimed at exploring the involvement of other taxa in PCB dechlorination using sediment-free microcosms (SFMs) and the Delor PCB mixture. High rates of congener dehalogenation (up to 96%) were attained in long-term incubations of up to 692 days. Bacterial communities were dominated by Chloroflexi, Proteobacteria, and Firmicutes, among strictly simplified community structures composed of 12 major phyla only. In a first batch of SFMs, Dehalococcoides mccartyi closely affiliated with strains CG4 and CBDB1 was considered as the main actor associated with congener dehalogenation. Addition of 2-bromoethanesulfonate (BES), a known inhibitor of methanogenic activity in a second batch of SFMs had an adverse effect on the abundance of Dehalococcoides sp. Only two sequences affiliated to this Genus could be detected in two (out of six) BES-treated SFMs, contributing to a mere 0.04% of the communities. BES-treated SFMs showed very different community structures, especially in the contributions of organisms involved in fermentation and syntrophic activities. Indirect evidence provided by both statistical and phylogenetic analysis validated the implication of a new cluster of actors, distantly affiliated with the Family Geobacteraceae (Phylum δ-Proteobacteria), in the dehalogenation of low chlorinated PCB congeners. Members of this Family are known already for their dehalogenation capacity of chlorinated solvents. As a result, the present study widens the knowledge for the phylogenetic reservoir of indigenous PCB dechlorinating

  5. Exposure to mercury and Aroclor 1268 congeners in least terns (Sternula antillarum) in coastal Georgia, USA.

    PubMed

    Robinson, Gabrielle L; Mills, Gary L; Lindell, Angela H; Schweitzer, Sara H; Hernandez, Sonia M

    2015-08-01

    Concentrations of total mercury and the rare PCB mixture Aroclor 1268 in least terns (Sternula antillarum), a colonially-nesting, piscivorous seabird, in the Turtle River estuary and other coastal sites in Georgia, USA, were investigated. The Turtle River estuary is the location of the Linden Chemical Plant (LCP) Superfund site, a site prioritized by USA law for immediate remediation, where industries released effluent containing these contaminants until 1994. Aroclor 1268 is a highly-chlorinated PCB mixture that was used and released exclusively at the LCP site and nowhere else in the south eastern USA. High concentrations of Aroclor 1268 congeners and mercury have been documented in biota local to LCP, but no studies report concentrations in high trophic level, piscivorous birds such as least terns. We collected feathers and feces from chicks, and eggs from adults, at nesting colonies along the Georgia coast to analyze contaminant loads (in dry weight ppb). Mean Aroclor 1268 mixture concentrations in eggs (≤16,329 ppb) were highest at colonies in and just outside LCP, and decreased with increasing distance (up to 110 km) from LCP, but the Aroclor 1268 signature congener mixture was present at all sites. Mercury concentrations in eggs (≤3370 ppb), feathers (≤5950 ppb), and feces (≤417 ppb), were present at all sites, but did not vary significantly among sites. This report confirms the extensive dispersal of Aroclor 1268 congeners (approximately 110 km north and 70 km south of its point source) via bioaccumulation and trophic transfer. PMID:26166752

  6. The Belgian PCB/dioxin incident: analysis of the food chain contamination and health risk evaluation.

    PubMed

    Bernard, Alfred; Broeckaert, Fabrice; De Poorter, Geert; De Cock, Ann; Hermans, Cédric; Saegerman, Claude; Houins, Gilbert

    2002-01-01

    The Belgian PCB incident occurred at the end of January 1999 when a mixture of polychlorinated biphenyls (PCBs) contaminated with dioxins was accidentally added to a stock of recycled fat used in the production of animal feeds. Although signs of poultry poisoning were noticed by February, 1999, the source and the extent of the contamination were discovered only in May 1999, when it appeared that more than 2500 farms could have been supplied with contaminated feeds. This resulted in a major food crisis, which rapidly extended to the whole country and could be resolved only by the implementation of a large PCB/dioxin food monitoring program. Screening for PCB contamination was based on the determination of the seven PCB markers. When PCB concentrations exceeded the tolerance levels of 0.1 (milk), 0.2 (poultry, bovine, and pig meat), or 1 (animal feed) microg/g fat, dioxins (17 PCDD/Fs congeners) were also determined. At the end of December 1999, the database contained the results of more than 55,000 PCB and 500 dioxin analyses. The study of PCB levels and profiles in contaminated feeds delivered to poultry or pig farms confirmed that the Belgian PCB incident was due to a single source of PCB oil introduced into the food chain at the end of January 1999. This PCB oil had a congeners pattern closely matched to a mixture of Aroclor 1260/1254 in the proportion 75/25. The total amount of PCBs added to recycled fats was estimated at 50 kg (sum of the seven markers) or approximately 150 kg total PCBs, which corresponds to about 100 liters of PCB oil. This PCB mixture contained about 1g TEQ dioxins (more than 90- contributed by PCDFs) and about 2g TEQ dioxin-like PCBs. The proportions of PCB 52 and 101 congeners were fairly constant in animal feeds, excluding the possibility of secondary contamination due to fat recycling from contaminated animals. The highest concentrations of PCBs and dioxins were found in poultry and especially in the reproduction animals (hens and chicks

  7. PCB breakdown by anaerobic microorganisms

    SciTech Connect

    Not Available

    1989-03-01

    Recently, altered PCB cogener distribution patterns observed in anaerobic sediment samples from the upper Hudson River are being attributed to biologically mediated reductive dechlorination. The authors report their successful demonstration of biologically mediated reductive dechlorination of an Aroclor mixture. In their investigation, they assessed the ability of microorganisms from PCB-contaminated Hudson River sediments (60-562 ppm PCBs) to dechlorinate Aroclor 1242 under anaerobic conditions by eluting microorganisms from the PCB- contaminated sediments and transferring them to a slurry of reduced anaerobic mineral medium and PCB-free sediments in tightly stoppered bottles. They observed dechlorination to be the most rapid at the highest PCB concentration tried by them.

  8. Diadenosine tetraphosphate (AP{sub 4}A) levels in muscle tissue as a potential biomarker of PCB and TCDD exposure

    SciTech Connect

    Nordone, A.; Grant, T.; Saranko, C.; Pivorun, E.

    1995-12-31

    During the past two decades a group of purine nucleotides, the diadenosine polyphosphates, have gained increasing attention. One of these compounds, diadenosine tetraphosphate (AP{sub 4}A), has been demonstrated to modulate a variety of cellular events, including intracellular signaling during adaptive responses to cellular stress. The authors have recently demonstrated that changes in AP{sub 4}A levels in venous and arterial blood are related to periods of major trauma during corrective spinal surgery. Using Deermice (Peromyscus maniculatus) they investigated whether changes in the concentration of AP{sub 4}A in muscle tissue could be used as a biomarker of chemically induced stress. Using intraperitoneal administration, animals were exposed to either a mixture of PCB congeners (Aroclor 1254), a coplanar PCB (PCB 169), a noncoplanar PCB (PCB 153) or TCDD for a period of 11 days. The coplanar PCB and TCDD decreased AP{sub 4}A concentrations in dose-dependent manner, whereas the noncoplanar PCB increased concentrations in a dose-dependent manner. Aroclor 1254 reduced AP{sub 4}A concentration to a similar level at all doses. These results indicate that PCBs and TCDD modulate AP{sub 4}A concentrations in muscle tissue in a manner that is both dose and structure dependent. It is possible that AP{sub 4}A could be used as a marker of the level of exposure to PCBs and dioxin and as an indicator of the congeners involved.

  9. Toxic cell concentrations of three polychlorinated biphenyl congeners in the green alga, Selenastrum capricornutum

    SciTech Connect

    Mayer, P. |; Halling-Soerensen, B.; Nyholm, N.; Sijm, D.T.H.M.

    1998-09-01

    Algal growth inhibition tests were performed with the unicellular green alga Selenastrum capricornutum and three {sup 14}C-labeled polychlorinated biphenyl (PCB) congeners. Toxicity was related to external aqueous concentrations and additionally to internal algal bound PCB concentrations. Estimates of the concentrations at 50% effectiveness (EC50s) for the three PCB congeners ranged within a factor of 17 when based on measured aqueous concentrations. When based on internal toxicant concentrations the corresponding range was 6.7 to 14.3 mmol/kg wet weight. Thus, changing the basis from external to internal concentrations reduced the range by almost one order of magnitude. Additional toxic cell concentrations of five monoaromatic compounds and S. capricornutum were calculated from literature data to be in the same order of magnitude as the experimental toxic cell concentrations for the PCBs, whereas EC50 values for all substances ranged by more than four orders of magnitude. The experimental and calculated data indicate that observed differences in the estimated EC50 values were mainly due to differences in bioconcentration behavior rather than to different intrinsic toxicities. These findings are in agreement with the concept of baseline toxicity, meaning that a number of hydrophobic organics exerts their acute toxicity by one relatively nonspecific mode of action.

  10. Methyl sulfone PCB and DDE metabolites in the polar bear (Ursus maritimus) food chain

    SciTech Connect

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

    1995-12-31

    An important Arctic marine food chain is polar bear, ringed seal (Phoca hispida) and Arctic cod (Boreogadus saida). The Arctic is relatively uncontaminated by chlorinated hydrocarbon contaminants (CHCs). However, high levels of CHCs are bioaccumulated through the marine food web. Methyl sulfone (MeSO{sub 2})-PCB and -DDE metabolites are major CHCs in polar bear, although the proportion of MeSO{sub 2}-PCBs derived from PCB metabolism and/or MeSO{sub 2}-PCB bioaccumulation from the diet is unknown. For this reason, the structure and concentration of MeSO{sup 2}-PCB and -DDE metabolites, PCBs and DDE were determined in whole body Arctic cod, the liver, adipose, lung and muscle of ringed seal and ten tissues of polar bear from the Resolute Bay area of the Canadian Arctic. Preliminary analysis of the ratios of MeSO{sub 2}-PCBs in bear fat and liver to their parent PCBs in seal blubber suggested that CB-49 and CB-87 result in a higher proportion of metabolites in bear than the other PCB congeners, assuming that the MeSO{sup 2}-PCBs are not themselves accumulated from the diet. Bio-availability of the precursor PCBs for subsequent metabolism may also be a factor. The absence in bears of MeSO{sub 2}-metabolites of other metabolizable PCBs in seal may indicate that some MeSO{sub 2}-PCBs are not formed or that they are formed and further metabolized. The MeSO{sub 2}-PCB and -DDE levels and congener patterns among seal and bear tissues and the difference in tissue distribution between species will also be compared. In polar bear, the s-MeSO{sub 2}-PCB to S-PCB and s-MeSO{sub 2}-DDE to DDE ratios were highest in liver, indicating preferred storage.

  11. PCB-Caulk Replacement Project Johnson Space Center Houston, TX

    NASA Technical Reports Server (NTRS)

    Young, William M.; Stanch, Penney M.; Molenda, William

    2011-01-01

    Wet method reduced exposure by minimizing overall respirable particulate release. Dry method didn't introduce delays for primer/caulk application. Removed caulks came in many forms, from dry powdery to tarry sticky. Varying textures were not sampled or packaged differently. During the course of the project, EPA modified recommended practices to include full containment for exterior caulk removal. Changes are ongoing. Initial recommendations were directed to school buildings. EPA is researching risks due to caulk. Exposure guidance lacking except for 2 of 209 PCB congeners. Work was safely completed on schedule and under budget.

  12. A Method to Simultaneously Improve PCB Radiolysis Rates in Oil and to Close the Chlorine Mass Balance

    SciTech Connect

    Mincher, Bruce Jay; Curry, R. C.; Brey, R.

    2000-06-01

    The addition of alkaline 2-propanol to isooctane and transformer oil solutions of PCBs was found to increase the rate of PCB dechlorination by -radiolysis. Simultaneously, it facilitates the closure of the chlorine mass balance. The chlorine liberated from PCBs irradiated in alkaline 2-propanol-spiked solutions precipitated as an inorganic salt in a stoichiometric amount. This was demonstrated for an individual PCB congener (PCB 155) in isooctane and for Aroclor 1260 in transformer oil. Radiolysis rates are reported in terms of dose constants, d (kGy-1), the exponential rate constant for PCB decomposition with respect to absorbed dose. These are the highest decomposition rates yet reported for the radiolytic treatment of PCB-contaminated transformer oil.

  13. Effects of PCB126 and PCB153 on telomerase activity and telomere length in undifferentiated and differentiated HL-60 cells.

    PubMed

    Xin, Xing; Senthilkumar, P K; Schnoor, Jerald L; Ludewig, Gabriele

    2016-02-01

    PCBs are persistent organic pollutants that are carcinogenic and immunotoxic and have developmental toxicity. This suggests that they may interfere with normal cell maturation. Cancer and stem/progenitor cells have telomerase activity to maintain and protect the chromosome ends, but lose this activity during differentiation. We hypothesized that PCBs interfere with telomerase activity and the telomere complex, thereby disturbing cell differentiation and stem/progenitor cell function. HL-60 cells are cancer cells that can differentiated into granulocytes and monocytes. We exposed HL-60 cells to PCB126 (dioxin-like) and PCB153 (nondioxin-like) 6 days before and during 3 days of differentiation. The differentiated cells showed G0/G1 phase arrest and very low telomerase activity. hTERT and hTR, two telomerase-related genes, were downregulated. The telomere shelterins TRF1, TRF2, and POT1 were upregulated in granulocytes, and TRF2 was upregulated and POT1 downregulated in monocytes. Both PCBs further reduced telomerase activity in differentiated cells, but had only small effects on the differentiation and telomere-related genes. Treatment of undifferentiated HL-60 cells for 30 days with PCB126 produced a downregulation of telomerase activity and a decrease of hTERT, hTR, TRF1, and POT1 gene expression. With PCB153, the effects were less pronounced and some shelterin genes were increased after 30 days of exposure. With each PCB, no differentiation of cells was observed and cells continued to proliferate despite reduced telomerase activity, resulting in shortened telomeres after 30 days of exposure. These results indicate cell-type and PCB congener-specific effects on telomere/telomerase-related genes. Although PCBs do not seem to strongly affect differentiation, they may influence stem or progenitor cells through telomere attrition with potential long-term consequences for health. PMID:26330309

  14. Assays of polychlorinated biphenyl congeners and co-contaminated heavy metals in the transgenic Arabidopsis plants carrying the recombinant guinea pig aryl hydrocarbon receptor-mediated β-glucuronidase reporter gene expression system.

    PubMed

    Shimazu, Sayuri; Ohta, Masaya; Ohkawa, Hideo; Ashida, Hitoshi

    2012-01-01

    The transgenic Arabidopsis plant XgD2V11-6 carrying the recombinant guinea pig (g) aryl hydrocarbon receptor (AhR)-mediated β-glucuronidase (GUS) reporter gene expression system was examined for assay of polychlorinated biphenyl (PCB) congeners and co-contaminated heavy metals. When the transgenic Arabidopsis plants were treated with PCB126 (toxic equivalency factor; TEF: 0.1) and PCB169 (TEF: 0.03), the GUS activity of the whole plants was increased significantly. After treatment with PCB80 (TEF: 0), the GUS activity was nearly the same level as that treated with 0.1% dimethylsulfoxide (DMSO) as a vehicle control. After exposure to a 1:1 mixture of PCB126 and PCB169, the GUS activity was increased additively. However, after exposure to a mixture of PCB126 and PCB80, the GUS activity was lower than that of the treatment with PCB126 alone. Thus, PCB80 seemed to be an antagonist towards AhR. When the transgenic plants were treated with each of the heavy metals Fe, Cu, Zn, Cd and Pb together with PCB126, Cd and Pb increased the PCB126-induced GUS activity. On the other hand, Fe, Cu and Zn did not affect the PCB126-induced GUS activity. In the presence of the biosurfactant mannosylerythritol lipid-B (MEL-B) and the carrier protein bovine serum albumin (BSA), the PCB126-induced GUS activity was increased, but the Cd-assisted PCB126-induced GUS activity was not affected. Thus, MEL-B and BSA seemed to increase uptake and transport of PCB126, respectively. PMID:22938576

  15. Assessment of the Polychlorinated Biphenyl (PCB) Occurrence in Copper Sulfates and the Influential Role of PCB Levels on Grapes

    PubMed Central

    Li, Xiaomin; Su, Xiaoou

    2015-01-01

    Copper sulfates (CuSO4) are widely used as the primary component of fungicides in the grape industry. The agricultural-grade CuSO4 that we collected from Chinese nationwide markets were found to be contaminated by polychlorinated dibenzo-p-dioxins and dibenzofurans and high levels of polychlorinated biphenyls (Σ19PCBs: 0.32~9.51 ng/g). In the following research, we studied the impact of CuSO4 application on PCB levels in grape products through a field experiment, and conducted a national survey to speculate the role that CuSO4 played on the occurrence of PCB in grapes. In the field experiment, an obvious increase of PCBs in grape leaves (from 174 to 250 pg/g fw) was observed after Bordeaux mixture (the main component of which is CuSO4) application. As to the main PCB congener in CuSO4, the most toxic CB 126 (toxic equivalency factor = 0.1) also increased in grape peels (from 1.66 to 2.93 pg/g fw) after pesticide spray. Both the correlation study and the principal component analysis indicated that environmental factors were dominant PCB contributors to grapes, and grapes from e-waste dismantling area containing the highest PCBs also proved the notion. It is worth noting that this report describes the first research examining PCBs in CuSO4 and its influence on agricultural products to date. PMID:26658158

  16. Assessment of the Polychlorinated Biphenyl (PCB) Occurrence in Copper Sulfates and the Influential Role of PCB Levels on Grapes.

    PubMed

    Li, Xiaomin; Su, Xiaoou

    2015-01-01

    Copper sulfates (CuSO4) are widely used as the primary component of fungicides in the grape industry. The agricultural-grade CuSO4 that we collected from Chinese nationwide markets were found to be contaminated by polychlorinated dibenzo-p-dioxins and dibenzofurans and high levels of polychlorinated biphenyls (Σ19PCBs: 0.32~9.51 ng/g). In the following research, we studied the impact of CuSO4 application on PCB levels in grape products through a field experiment, and conducted a national survey to speculate the role that CuSO4 played on the occurrence of PCB in grapes. In the field experiment, an obvious increase of PCBs in grape leaves (from 174 to 250 pg/g fw) was observed after Bordeaux mixture (the main component of which is CuSO4) application. As to the main PCB congener in CuSO4, the most toxic CB 126 (toxic equivalency factor = 0.1) also increased in grape peels (from 1.66 to 2.93 pg/g fw) after pesticide spray. Both the correlation study and the principal component analysis indicated that environmental factors were dominant PCB contributors to grapes, and grapes from e-waste dismantling area containing the highest PCBs also proved the notion. It is worth noting that this report describes the first research examining PCBs in CuSO4 and its influence on agricultural products to date. PMID:26658158

  17. Distribution and uptake of key polychlorinated biphenyl and polybrominated diphenyl ether congeners in benthic infauna relative to sediment organic enrichment.

    PubMed

    Burd, Brenda J; Macdonald, Tara A; Macdonald, Robie W; Ross, Peter S

    2014-10-01

    As part of a broader study of budgets, transport, and bioaccumulation of persistent organic contaminants in the Strait of Georgia, Canada, matching samples of sediment and bulk benthos were collected near two marine sewage outfalls, two large urban harbours, and background areas. Samples were analyzed for polychlorinated biphenyl (PCB) and polybrominated diphenyl ether (PBDE) congeners. We present data for those congeners that fell within the top six rankings by concentration (23 PCBs and 10 PBDEs) within at least one of the environmental media measured in other studies (air, water, sediments, benthos, pelagic biota). Multifactor regression analyses incorporating sediment characteristics (total organic carbon, fines) predicted uptake (r (2) = 0.74 to 0.98, p < 0.04) over the range of congeners and habitats examined. PBDEs were taken up by biota more readily than PCBs, suggesting a large, potentially available biological reservoir of PBDEs in sediments. Dominant congeners in benthos comprised PBDEs 47, 99, 209, and 100 and PCBs 138/163, 153, 101, 118, and 110. PBDE uptake was anomalously high near one wastewater outfall, likely due to selective feeding on PBDE-enriched particulates from that source. Conversely, outfalls supply food and sediments with PCB concentrations similar to ambient sediments. However, organic enrichment of sediments near outfalls clearly enhanced PCB uptake by benthos, probably due to greatly increased biomass turnover near these sources. Data suggest there to be an initial reservoir of PCBs in newly settled juvenile benthos, which is much less evident for PBDEs. This is likely a consequence of the ecosystem-wide distribution of legacy PCBs but not the more current-use PBDEs. Congener-uptake patterns were dependent on source and input dynamics, feeding methods, and contaminant metabolism or debromination, particularly of deca-BDE. PMID:24699838

  18. An assessment of PCB degradation by microogransims including methods for measuring mineralization

    SciTech Connect

    Hadden, C.; Edenborn, H.; Osborne, T.; Holdsworth, G.; Revis, N.

    1990-12-31

    These studies sought to isolate and identify organism(s) from PCB contaminated soil and sediment that degrade PCB; to provide information on the potential of organisms in soil samples taken from a PCB-contaminated area to mineralize or dechlorinate PCB congeners; to assess potential enhancement of PCB biodegradation as a result of nutritional amendment of the samples; and to carry out analyses of successive lysimeter samples to determine whether field treatments have had an effect on the capacity of soil microbes to mineralize PCBS. We have expended considerable effort to validate the fractionation procedure used to assess mineralization and conversion of PCB substrates. The assessment relies on the ability to measure [{sup 14}C]-labeled CO{sub 2} in the presence of potentially volatile [{sup 14}C]-labeled PCB and degradation products to differentiate between volatile and non-volatile [{sup 14}C]-labeled compounds between water-soluble products of metabolism and a mixture of unchanged substrate and other water-insoluble products and between metabolism and loss or non-extractability of the substrate.

  19. Polychlorinated biphenyl source attribution in Green Bay, Wisconsin, USA, using multivariate similarity among congener profiles in sediment samples.

    PubMed

    Cacela, Dave; Beltman, Douglas J; Lipton, Joshua

    2002-08-01

    Polychlorinated biphenyl (PCB) congener concentrations measured in 1,189 sediment samples from Green Bay (MI/WI, USA), Lake Michigan (MI/WI, USA), and the Fox River (WI, USA) were analyzed statistically to evaluate whether PCB congener profiles in outer Green Bay are more similar to those observed in inner Green Bay or Lake Michigan. Similarities among PCB profiles were assessed with complementary multivariate analysis techniques: Principal component analysis (PCA), cluster analysis, and classification trees. The PCA indicated that profiles in outer Green Bay are distinct from those of inner Green Bay or Lake Michigan but are more similar to those of inner Green Bay. The outer bay profiles are dissimilar to profiles that would result from a simple process of mixing contaminated sediments from the inner bay with Lake Michigan sediments and, therefore, support the conclusion that contaminants in outer Green Bay come from discharges of the Fox River. Several classification trees based on small sets of congener proportions defined simple rules that consistently distinguished the regional profiles. Application of these rules to classify the outer bay samples suggests that the profiles of less than 7% of outer bay samples are similar to Lake Michigan profiles. These results are interpreted with respect to physical transport and chemical weathering processes that may account for the observed differences. PMID:12152758

  20. Congener specific determination and enantiomeric ratios of chiral polychlorinated biphenyls in striped dolphins (Stenella coeruleoalba) from the Mediterranean Sea

    SciTech Connect

    Reich, S.; Schurig, V.; Jimenez, B.; Hernandez, L.M.; Gonzalez, M.J.; Marsili, L.

    1999-06-01

    Blubber and liver samples from six striped dolphins (Stenella coeruleoalba) found dead in the Mediterranean Sea in 1989--1990 were tested for 37 coplanar and chiral polychlorinated biphenyls (PCBs), including the enantiomeric ratios of 9 chiral PCBs. The method includes a fractionation step using HPLC (PYE column) for separating the PCBs according to the number of chlorine atoms in the ortho positions. HRGC/ECD and HRGC/LRMS with an a chiral column (DB-5) were used to determine the PCB congeners. The enantiomeric ratios of nine chiral PCBs were determined by HRGC/LRMS (SIM) with a chiral column (Chirasil-Dex) and by MDGC as the confirmatory technique. The total PCB concentration (sum of 37 congeners) ranged from 7.2 to 89.6 {micro}g/g (wet weight) and from 0.52 to 29.2 {micro}g/g (wet weight) for blubber and liver samples, respectively. PCB profiles were dominated by congeners 138, 153, 170, and 180. The toxic equivalent values (TEQ) ranged from 0.17 to 3.93 ng/g (wet weight) and from 0.02 to 0.73 ng/g (wet weight) for blubber and liver samples, respectively. PCBs 95, 132, 135, 149, and 176 revealed an enantiomeric excess of the second eluted enantiomer in almost all of the samples, whereas PCBs 136 and 174 were racemic or almost racemic. PCBs 88 and 91 were under the detection limits of the methodology used.

  1. Congener-specific determination of polychlorinated biphenyls and organochlorine pesticides in human milk from Norwegian mothers living in Oslo

    SciTech Connect

    Johansen, H.R.; Becher, G.; Polder, A.; Skaare, J.U.

    1994-12-31

    Human milk samples from 28 mothers at Oslo City Hospital, Norway, were collected in 1991 and analyzed for individual polychlorinated biphenyl (PCB) congeners, IUPAC numbers 28, 74, 99, 101, 105, 114, 118, 128, 138, 141, 153, 156, 157, 170, 180, 194, and 206, plus selected non-ortho-substituted compounds, IUPAC numbers 77, 126, and 169. Sum DDTs (sum of concentrations of DDT and related compounds), hexachlorobenzene (HCB), oxychlordane, transnonachlor, and sum hexachlorocyclohexanes (HCHs) (sum of concentrations of {alpha}-HCH, {beta}-HCH, and {gamma}-HCH) were also determined. The mean levels of sum DDTs, HCB, oxychlordane, transnonachlor, and sum HCHs were 338, 41, 9, 19, and 36 ng/g, respectively, in human milk fat. p,p{prime}-DDE and {beta}-HCH accounted for 81 and 93% of sum DDTs and sum HCHs, respectively. The mean level of sum PCBs (sum of mean concentrations of 20 individual congeners) was 372 ng/g milk fat. A very good correlation was found between sum PCBs and PCB-153 (r = .97). Sum PCBs determined on a capillary column was found to account for 62-79% of total PCBs calculated by using the packed column method used in previous human milk surveys in Norway. Comparison with previous results revealed that the mean sum PCB, HCB and sum DDT levels were decreased by 70, 65, and 75%, respectively during the past 9 yr. The contribution of individual PCDD/PCDF (earlier Norwegian study) and non- and mono-ortho-substituted PCB congeners to the total calculated toxic equivalent values was assessed, and the PCBs were found to constitute a major part of the TCDD equivalents in human milk, with PCB-126 as the main contributor. 40 refs., 6 figs., 2 tabs.

  2. Cucurbita spp. and Cucumis sativus enhance the dissipation of polychlorinated biphenyl congeners by stimulating soil microbial community development.

    PubMed

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

    2014-01-01

    A number of Cucurbita species have the potential to extract polychlorinated biphenyls (PCBs) from soil, but their impact on the soil microbial communities responsible for PCB degradation remains unclear. A greenhouse experiment was conducted to investigate the effect of three Cucurbita and one Cucumis species on PCB dissipation and soil microbial community structure. Compared to the unplanted control, enhanced losses of PCBs (19.5%-42.7%) were observed in all planted soils. Cucurbita pepo and Cucurbita moschata treatments were more efficient in PCB dissipation, and have similar patterns of soil phospholipid fatty acids (PLFAs) and PCB congener profiles. Cucurbita treatments tend to have higher soil microbial biomass than Cucumis. Gram-negative (G(-)) bacteria were significantly correlated with PCB degradation rates (R(2) = 0.719, p < 0.001), while fungi and G(-) bacteria were correlated with dissipation of the penta homologue group (R(2) = 0.590, p < 0.01). Therefore, Cucurbita related soil microorganisms could play an important role in remediation of PCB contaminated soils. PMID:24077568

  3. Influence of colloids on sediment-water partition coefficients of polychlorobiphenyl congeners in natural waters

    SciTech Connect

    Baker, J.E.; Capel, P.D.; Eisenreich, S.J.

    1986-11-01

    Measurements of sediment-water partitioning of polychlorobiphenyl (PCB) congeners in Lake Superior provide some of the first field evidence demonstrating the importance of colloids to the fates of highly hydrophobic organic pollutants. Laboratory-derived correlations between sediment-water distribution coefficients and properties of both the contaminant (octanol-water partition coefficient) and the suspended solids (organic carbon content, concentration) do not accurately predict PCB speciation in Lake Superior. This failure can be explained by the presence of colloidal matter with which contaminants may associate and the very low solids concentrations in oligotrophic surface waters. A surprising consequence of such colloid associations is that the observed sediment-water distribution coefficients are independent of properties of highly hydrophobic compounds. A three-phase model including nonfilterable microparticles and macromolecular organic matter shows that colloidal-associated contaminants may be the dominant species in most surface waters. Colloidal associations are therefore likely to significantly impact the geochemistry of hydrophobic pollutants.

  4. The dioxin contamination incident in Ireland, 2008: analytical results and congener patterns.

    PubMed

    Tlustos, C; Sheridan, M; O'Sullivan, D; Anderson, W; Flynn, A

    2012-01-01

    A porcine fat sample taken as part of the national residues monitoring programme in 2008 led to the detection of a major feed contamination incidence in the Republic of Ireland. The source of the contamination was traced back to the use of contaminated oil in a direct-drying feed operation system. Congener profiles in animal fat and feed samples showed a high level of consistency and pinpointed the likely source of fuel contamination to be a highly chlorinated commercial PCB mixture. PMID:22035259

  5. In silico predictive studies of mAHR congener binding using homology modelling and molecular docking.

    PubMed

    Panda, Roshni; Cleave, A Suneetha Susan; Suresh, P K

    2014-09-01

    The aryl hydrocarbon receptor (AHR) is one of the principal xenobiotic, nuclear receptor that is responsible for the early events involved in the transcription of a complex set of genes comprising the CYP450 gene family. In the present computational study, homology modelling and molecular docking were carried out with the objective of predicting the relationship between the binding efficiency and the lipophilicity of different polychlorinated biphenyl (PCB) congeners and the AHR in silico. Homology model of the murine AHR was constructed by several automated servers and assessed by PROCHECK, ERRAT, VERIFY3D and WHAT IF. The resulting model of the AHR by MODWEB was used to carry out molecular docking of 36 PCB congeners using PatchDock server. The lipophilicity of the congeners was predicted using the XLOGP3 tool. The results suggest that the lipophilicity influences binding energy scores and is positively correlated with the same. Score and Log P were correlated with r = +0.506 at p = 0.01 level. In addition, the number of chlorine (Cl) atoms and Log P were highly correlated with r = +0.900 at p = 0.01 level. The number of Cl atoms and scores also showed a moderate positive correlation of r = +0.481 at p = 0.01 level. To the best of our knowledge, this is the first study employing PatchDock in the docking of AHR to the environmentally deleterious congeners and attempting to correlate structural features of the AHR with its biochemical properties with regards to PCBs. The result of this study are consistent with those of other computational studies reported in the previous literature that suggests that a combination of docking, scoring and ranking organic pollutants could be a possible predictive tool for investigating ligand-mediated toxicity, for their subsequent validation using wet lab-based studies. PMID:23081860

  6. Sedimentary Records of Non-Aroclor and Aroclor PCB mixtures in the Great Lakes

    PubMed Central

    HU, DINGFEI; MARTINEZ, ANDRES; HORNBUCKLE, KERI C.

    2012-01-01

    Three sediment cores from Lake Ontario, Lake Erie and Indiana Harbor Ship Canal were collected, segmented and analyzed for Aroclor and non-Aroclor polychlorinated biphenyl congeners (PCBs). PCBs associated with the commercially produced Aroclor mixtures 1248 and 1254 dominate the sediment signal and the sum of all congenersPCB) peaks in concentration and accumulation around 1970 in the Great Lakes. This trend is very similar to Aroclor production history. In the Indiana Harbor Ship Canal, PCBs appear around 1935 and remain at very high levels between 1940 and 1980, probably reflecting the history of use at the nearby steel mill. In contrast, the non-Aroclor PCBs in the Lake Ontario and IHSC sediment cores, including PCB11 and heavily chlorinated congeners PCB206, 207, 208 and 209 reach a peak in the 1950s, decline and peak again in the 1970s or in the early 1980s. All five congeners have been previously measured in commercial paint pigment. PCB11 was found to peak about 5 years later than ΣPCBs, and is probably associated with the production or use history of diarylide yellow pigments. The temporal distribution profiles of these non-Aroclor PCBs are well correlated with the production history of paint pigments and dyes. Although it is well known that the production of Aroclor PCBs is preserved in Great Lakes sediments, this study is the first to show that production of non-Aroclors are also preserved in the sediments as a record of long term trends in environmental exposure. PMID:23538476

  7. Sedimentary Records of Non-Aroclor and Aroclor PCB mixtures in the Great Lakes.

    PubMed

    Hu, Dingfei; Martinez, Andres; Hornbuckle, Keri C

    2011-06-01

    Three sediment cores from Lake Ontario, Lake Erie and Indiana Harbor Ship Canal were collected, segmented and analyzed for Aroclor and non-Aroclor polychlorinated biphenyl congeners (PCBs). PCBs associated with the commercially produced Aroclor mixtures 1248 and 1254 dominate the sediment signal and the sum of all congenersPCB) peaks in concentration and accumulation around 1970 in the Great Lakes. This trend is very similar to Aroclor production history. In the Indiana Harbor Ship Canal, PCBs appear around 1935 and remain at very high levels between 1940 and 1980, probably reflecting the history of use at the nearby steel mill. In contrast, the non-Aroclor PCBs in the Lake Ontario and IHSC sediment cores, including PCB11 and heavily chlorinated congeners PCB206, 207, 208 and 209 reach a peak in the 1950s, decline and peak again in the 1970s or in the early 1980s. All five congeners have been previously measured in commercial paint pigment. PCB11 was found to peak about 5 years later than ΣPCBs, and is probably associated with the production or use history of diarylide yellow pigments. The temporal distribution profiles of these non-Aroclor PCBs are well correlated with the production history of paint pigments and dyes. Although it is well known that the production of Aroclor PCBs is preserved in Great Lakes sediments, this study is the first to show that production of non-Aroclors are also preserved in the sediments as a record of long term trends in environmental exposure. PMID:23538476

  8. Congener-specific polychlorinated biphenyls and the prevalence of diabetes in the Saku Control Obesity Program (SCOP).

    PubMed

    Tanaka, Takahisa; Morita, Akemi; Kato, Masayuki; Hirai, Tetsuya; Mizoue, Tetsuya; Terauchi, Yasuo; Watanabe, Shaw; Noda, Mitsuhiko

    2011-01-01

    The prevalence of diabetes is increasing globally. In addition to established risk factors for diabetes, such as diet, inactivity, overweight and obesity, the involvement of persistent organic pollutants, including dioxins and polychlorinated biphenyls (PCBs), has also been suggested to be a possible, but controversial, cause of this epidemic. The present study investigated the association between blood PCB congener levels and the prevalence of diabetes among middle-aged, overweight and obese Japanese participants in the Saku Control Obesity Program. One hundred seventeen participants had their congener-specific PCB levels measured in addition to undergoing routine blood analyses at the time of a medical checkup. Prevalent diabetes was defined according to two methods: definite diabetes was defined as people with an HbA1c level ≥ 6.9% or who were taking medication for diabetes, and all diabetes was defined as people with an HbA1c level ≥ 6.5%, a fasting plasma glucose level ≥ 126 mg/dL, or a history of doctor-diagnosed diabetes. A multiple logistic regression analysis was performed to analyze the association between the PCB levels and the prevalence of diabetes, with adjustments for sex, age, body mass index and total lipids. As a result, PCB 146 and 180 were positively associated and PCB 163/164 and 170 were negatively associated with the prevalence of definite diabetes. The significance of the association of PCB 180 and 163/164 with the prevalence of diabetes persisted regardless of the definition of diabetes or adjustments for total lipids, suggesting the possibility that these parameters may modify the risk of diabetes. PMID:21551956

  9. Historical profiles of PCB in dated sediment cores suggest recent lake contamination through the "halo effect".

    PubMed

    Naffrechoux, Emmanuel; Cottin, Nathalie; Pignol, Cécile; Arnaud, Fabien; Jenny, Jean-Philippe; Perga, Marie-Elodie

    2015-02-01

    We investigated the major sources of polychlorinated biphenyls (PCB) and interpreted the environmental fate processes of these persistent organic pollutants in the past and current PCB contamination of three large, urbanized, French peri-alpine lakes. Dated sediment cores were analyzed in order to reconstruct and compare the historical contamination in all three lakes. Stratigraphic changes of PCB contents and fluxes were considered as revealing the temporal dynamics of PCB deposition to the lakes and the distribution of the seven indicator congeners (further referred to as PCBi) as an indicator of the main contamination origin and pathway. Although located within a single PCB industrial production region, concentration profiles for the three lakes differed in timing, peak concentration magnitudes, and in the PCBi congeners compositions. PCBi fluxes to the sediment and the magnitude of the temporal changes were generally much lower in Lake Annecy (0.05-2 ng·cm(-2)·yr(-1)) as compared to Lakes Geneva (0.05-5 ng·cm(-2)·yr(-1)) and Bourget (5-290 ng·cm(-2)·yr(-1)). For all three lakes, the paramount contamination occurred in the early 1970s. In Lakes Annecy and Bourget, PCB fluxes have declined and plateaued at 0.5 and 8 ng·cm(-2)·yr(-1), respectively, since the early 1990s. In Lake Geneva, PCB fluxes have further decreased by the end of the XX(th) century and are now very low. For the most contaminated lake (Lake Bourget), the high PCBi flux (5-290 ng·cm(-2)·yr(-1)) and the predominance of heavy congeners for most of the time period are consistent with a huge local input to the lake. This still high rate of Lake Bourget is explained by transport of suspended solids from one of its affluents, polluted by an industrial point source. Intermediate historical levels and PCBi distribution over time for Lake Geneva suggest a mixed contamination (urban point sources and distant atmospheric transport), while atmospheric deposition to Lake Annecy explains its lowest

  10. Evaluation of background soil and air polychlorinated biphenyl (PCB) concentrations on a hill at the outskirts of a metropolitan city.

    PubMed

    Kuzu, S Levent; Saral, Arslan; Güneş, Gülten; Karadeniz, Aykut

    2016-07-01

    Air and soil sampling was conducted inside a forested area for 22 months. The sampling location is situated to the north of a metropolitan city. Average atmospheric gas and particle concentrations were found to be 180 and 28 pg m(-3) respectively, while that of soil phase was detected to be 3.2 ng g(-1) on dry matter, The congener pairs of PCB#4-10 had the highest contribution to each medium. TEQ concentration was 0.10 pg m(-3), 0.07 pg m(-3), 21.92 pg g(-1), for gas, particle and soil phases, respectively. PCB#126 and PCB#169 contributed to over 99% of the entire TEQ concentrations for each medium. Local sources were investigated by conditional probability function (CPF) and soil/air fugacity. Landfilling area and medical waste incinerator, located to the 8 km northeast, contributed to ambient concentrations, especially in terms of dioxin-like congeners. The industrial settlement (called Dilovasi being to the east southeast of 60 km distant) contributed from southeast direction. Further sources were identified by potential source contribution function (PSCF). Sources at close proximity had high contribution. Air mass transportation from Aliaga industrial region (being to the southwest of 300 km distant) moderately contributed to ambient concentrations. Low molecular weight congeners were released from soil body. 5-CBs and 6-CBs were close to equilibrium state between soil/air interfaces. PCB#171 was close to equilibrium and PCB#180 was likely to evaporate from soil, which constitute 7-CBs. PCB#199, representing 8-CBs deposited to soil. 9-CB (PCB#207) was in equilibrium between soil and air phases. PMID:27038903

  11. Determination of PCB Elimination Coefficients in Round Goby and Tubenose Goby.

    PubMed

    Sun, Xin; Johnson, Tim B; Drouillard, Ken G

    2016-09-01

    Whole-body elimination coefficients of polychlorinated biphenyls (PCBs) were determined in two Great Lakes invasive fish species, round goby (Neogobius melanostomus) and tubenose goby (Proterorhinus semilunaris). Elimination rates were determined for a set of model PCB congeners (n = 12 congeners) dosed to fish by intraperitoneal injection and allowed to depurate at a temperature of 21.4°C for 90 days. Eight PCBs (PCB 6, 21, 57, 62, 68, 89, 112 and 125) exhibited significant elimination by round goby and had corresponding half lives ranging from 13 to 39.8 days. For tubenose goby, four congeners (PCBs 21, 57, 62 and 68) exhibited significant elimination with half lives in the range from 18.8 to 48.8 days. Whole-body elimination rate coefficients were significantly higher for round gobies compared to tubenose goby. In both cases, PCB elimination rate coefficients were negatively related to chemical log KOW. PMID:27385369

  12. Unintentional PCB in chlorophenylsilanes as a source of contamination in environmental samples.

    PubMed

    Anezaki, Katsunori; Nakano, Takeshi

    2015-04-28

    This paper discusses the concentrations and congener patterns of PCBs unintentionally present in chlorophenylsilanes. Chlorophenylsilanes are used in the production of silicone-based adhesives and phenyl silicones. The concentration of PCBs in adhesives was found to range from not-detectable concentrations to 40mg/kg. The concentrations of PCBs in trichlorophenylsilane, dichlorodiphenylsilane, chlorotriphenylsilane, and diphenylsilanediol were 0.00072-2.7, 6.5-1,500, 0.019-1.1, and 0.12-120mg/kg, respectively. Dichlorodiphenylsilane and diphenylsilanediol, in particular, had high PCB concentrations. The PCB concentration of some specimens exceeded the 50mg/kg limit set by the transportation regulations of the Stockholm Convention. In the adhesives and chlorophenylsilanes, mono- and di-chlorinated biphenyls were detected in high proportions. The congeners detected in dichlorinated biphenyls had a structure in which one chlorine atom was substituted at each of the two aryls of the biphenyl backbone. This indicated that the chlorobenzene used for synthesizing chlorophenylsilanes undergoes dimerization. The congener and homologue patterns of the adhesives containing PCBs were similar to dichlorodiphenylsilane and diphenylsilanediol. It was concluded that the production of the adhesives is based on these substances. In addition, these results indicate that silicone-based products may become a source of PCBs in the environment, leading to irregular PCB values in environmental analysis. PMID:25634145

  13. Morphological and functional deterioration of the rat thyroid following chronic exposure to low-dose PCB118.

    PubMed

    Tang, Jin-Mei; Li, Wen; Xie, Yu-Chun; Guo, Hong-Wei; Cheng, Pei; Chen, Huan-Huan; Zheng, Xu-Qin; Jiang, Lin; Cui, Dai; Liu, Yun; Ding, Guo-Xian; Duan, Yu

    2013-11-01

    Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that can severely disrupt the synthesis and secretion of endocrine hormones. To investigate the effects of 2,3',4,4',5-pentachlorobiphenyl (PCB118) on thyroid structure and function, 40 male Wistar rats were divided into 4 equal treatment groups and administered vehicle or one of three doses of PCB118. The experimental groups received intraperitoneal (i.p.) injection of 10, 100, or 1000μg/kg/day PCB118, 5 days per week for 13 weeks, whereas the control group was injected with corn oil (vehicle). Serum concentrations of free thyroxine (FT4), free triiodothyronine (FT3) and thyroid stimulating hormone (TSH) were measured by radioimmunoassays. Histopathological and ultrastructural changes in the thyroid were observed under light microscopy and transmission electron microscopy (TEM). The mRNA expression levels of the sodium-iodide symporter (NIS) and thyroglobulin (TG) were quantified by real-time PCR. Increasing doses of PCB118 resulted in progressively lower FT3, FT4 and TSH concentrations in serum. Injection of PCB118 at all doses led to histopathological deterioration of the thyroid characterized by follicular hyperplasia and expansion, shedding of epithelial cells and fibrinoid necrosis. Follicle cells exhibited swollen or vacuolated endoplasmic reticula, as revealed by TEM. Exposure to PCB118 also caused significant decreases in NIS and TG mRNA expression levels. Chronic exposure to low-dose PCB118 and other PCB congeners may be a significant risk factor for thyroid diseases. PMID:23557935

  14. Exercise Attenuates PCB-Induced Changes in the Mouse Gut Microbiome

    PubMed Central

    Choi, Jeong June; Eum, Sung Yong; Rampersaud, Evadnie; Daunert, Sylvia; Abreu, Maria T.

    2013-01-01

    Background: The gut microbiome, a dynamic bacterial community that interacts with the host, is integral to human health because it regulates energy metabolism and immune functions. The gut microbiome may also play a role in risks from environmental toxicants. Objectives: We investigated the effects of polychlorinated biphenyls (PCBs) and exercise on the composition and structure of the gut microbiome in mice. Methods: After mice exercised voluntarily for 5 weeks, they were treated by oral gavage with a mixture of environmentally relevant PCB congeners (PCB153, PCB138, and PCB180; total PCB dose, 150 µmol/kg) for 2 days. We then assessed the microbiome by determination of 16S rRNA using microarray analysis. Results: Oral exposure to PCBs significantly altered the abundance of the gut microbiome in mice primarily by decreasing the levels of Proteobacteria. The activity level of the mice correlated with a substantial shift in abundance, biodiversity, and composition of the microbiome. Importantly, exercise attenuated PCB-induced changes in the gut microbiome. Conclusions: Our results show that oral exposure to PCBs can induce substantial changes in the gut microbiome, which may then influence their systemic toxicity. These changes can be attenuated by behavioral factors, such as voluntary exercise. PMID:23632211

  15. The effect of size and sex on PCB and PAH concentrations in crab Portunus pelagicus.

    PubMed

    Abdolahpur Monikh, Fazel; Hosseini, Mehdi; Rahmanpour, Shirin

    2014-03-01

    Polychlorinated biphenyl and polycyclic aromatic hydrocarbon concentrations in the hepatopancreas of blue swimming crab (Portunus pelagicus) from the north Persian Gulf were measured. In addition, the relationships between crab size (carapace width) and polychlorinated biphenyl (PCB) and polycyclic aromatic hydrocarbon (PAH) levels in hepatopancreas were investigated by linear regression analysis. Among the PCBs, congeners 110 and 153 were the most frequent and abundant. The results showed that, except in a few cases, significant relationships between PCB and PAH levels and crab size were positive. Comparison between male and female indicated that the average PCB16, 44, 153, and acenaphthylene, acenaphthene, and anthracene concentrations in hepatopancreas of male crab were found to be significantly higher than those found in the female crab. PMID:24150713

  16. Effects of age, adipose percent, and reproduction on PCB concentrations and profiles in an extreme fasting North Pacific marine mammal.

    PubMed

    Peterson, Sarah H; Hassrick, Jason L; Lafontaine, Anne; Thomé, Jean-Pierre; Crocker, Daniel E; Debier, Cathy; Costa, Daniel P

    2014-01-01

    Persistent organic pollutants, including polychlorinated biphenyls (PCBs), are widely distributed and detectable far from anthropogenic sources. Northern elephant seals (Mirounga angustirostris) biannually travel thousands of kilometers to forage in coastal and open-ocean regions of the northeast Pacific Ocean and then return to land where they fast while breeding and molting. Our study examined potential effects of age, adipose percent, and the difference between the breeding and molting fasts on PCB concentrations and congener profiles in blubber and serum of northern elephant seal females. Between 2005 and 2007, we sampled blubber and blood from 58 seals before and after a foraging trip, which were then analyzed for PCBs. Age did not significantly affect total PCB concentrations; however, the proportion of PCB congeners with different numbers of chlorine atoms was significantly affected by age, especially in the outer blubber. Younger adult females had a significantly greater proportion of low-chlorinated PCBs (tri-, tetra-, and penta-CBs) than older females, with the opposite trend observed for hepta-CBs, indicating that an age-associated process such as parity (birth) may significantly affect congener profiles. The percent of adipose tissue had a significant relationship with inner blubber PCB concentrations, with the highest mean concentrations observed at the end of the molting fast. These results highlight the importance of sampling across the entire blubber layer when assessing contaminant levels in phocid seals and taking into account the adipose stores and reproductive status of an animal when conducting contaminant research. PMID:24755635

  17. Effects of Age, Adipose Percent, and Reproduction on PCB Concentrations and Profiles in an Extreme Fasting North Pacific Marine Mammal

    PubMed Central

    Peterson, Sarah H.; Hassrick, Jason L.; Lafontaine, Anne; Thomé, Jean-Pierre; Crocker, Daniel E.; Debier, Cathy; Costa, Daniel P.

    2014-01-01

    Persistent organic pollutants, including polychlorinated biphenyls (PCBs), are widely distributed and detectable far from anthropogenic sources. Northern elephant seals (Mirounga angustirostris) biannually travel thousands of kilometers to forage in coastal and open-ocean regions of the northeast Pacific Ocean and then return to land where they fast while breeding and molting. Our study examined potential effects of age, adipose percent, and the difference between the breeding and molting fasts on PCB concentrations and congener profiles in blubber and serum of northern elephant seal females. Between 2005 and 2007, we sampled blubber and blood from 58 seals before and after a foraging trip, which were then analyzed for PCBs. Age did not significantly affect total PCB concentrations; however, the proportion of PCB congeners with different numbers of chlorine atoms was significantly affected by age, especially in the outer blubber. Younger adult females had a significantly greater proportion of low-chlorinated PCBs (tri-, tetra-, and penta-CBs) than older females, with the opposite trend observed for hepta-CBs, indicating that an age-associated process such as parity (birth) may significantly affect congener profiles. The percent of adipose tissue had a significant relationship with inner blubber PCB concentrations, with the highest mean concentrations observed at the end of the molting fast. These results highlight the importance of sampling across the entire blubber layer when assessing contaminant levels in phocid seals and taking into account the adipose stores and reproductive status of an animal when conducting contaminant research. PMID:24755635

  18. PCB Exposure and in Vivo CYP1A2 Activity among Native Americans

    PubMed Central

    Fitzgerald, Edward F.; Hwang, Syni-An; Lambert, George; Gomez, Marta; Tarbell, Alice

    2005-01-01

    Cytochrome P-450 1A2 (CYP1A2) is an enzyme involved in the metabolic activation of some carcinogens and is believed to be induced by xenobiotics. Very few studies, however, have investigated the association between environmental exposures and in vivo CYP1A2 activity in humans. To address this issue, a study was conducted of CYP1A2 activity among Native Americans exposed to polychlorinated biphenyls (PCBs) from the consumption of fish from the St. Lawrence River. At the Mohawk Nation at Akwesasne (in New York and in Ontario and Quebec, Canada), 103 adults were interviewed, and they donated blood for serum PCB analysis and underwent the caffeine breath test (CBT), a safe and noninvasive procedure that uses caffeine as a probe for CYP1A2 activity in vivo. The results supported the findings of other studies that CBT values are higher among smokers and men and lower among women who use oral contraceptives. Despite a relatively low average total PCB body burden in this population, the sum of serum levels for nine mono- or di-ortho-substituted PCB congeners showed positive associations with CBT values (p = 0.052 wet weight and p = 0.029 lipid adjusted), as did toxic equivalent quantities (TEQs; p = 0.091 for wet weight and 0.048 for lipid adjusted). Regarding individual congeners, serum levels of PCB-153, PCB-170, and PCB-180 were significantly correlated with CBT values. The results support the notion that CYP1A2 activity may be a marker of an early biological effect of exposure to PCBs in humans and that the CBT may be a useful tool to monitor such effects. PMID:15743714

  19. A cohort study of developmental polychlorinated biphenyl (PCB) exposure in relation to post-vaccination antibody response at 6-months of age

    SciTech Connect

    Jusko, Todd A.; De Roos, Anneclaire J.; Schwartz, Stephen M.; Paige Lawrence, B.; Palkovicova, Lubica; Nemessanyi, Tomas; Drobna, Beata; Fabisikova, Anna; Kocan, Anton; Sonneborn, Dean; Jahnova, Eva; Kavanagh, Terrance J.; Trnovec, Tomas; Hertz-Picciotto, Irva

    2010-05-15

    Background: Extensive experimental data in animals indicate that exposure to polychlorinated biphenyls (PCBs) during pregnancy leads to changes in offspring immune function during the postnatal period. Whether developmental PCB exposure influences immunologic development in humans has received little study. Methods: The study population was 384 mother-infant pairs recruited from two districts of eastern Slovakia for whom prospectively collected maternal, cord, and 6-month infant blood specimens were available. Several PCB congeners were measured in maternal, cord, and 6-month infant sera by high-resolution gas chromatography with electron capture detection. Concentrations of IgG-specific anti-haemophilus influenzae type b, tetanus toxoid, and diphtheria toxoid were assayed in 6-month infant sera using ELISA methods. Multiple linear regression was used to estimate the relation between maternal, cord, and 6-month infant PCB concentrations and the antibody concentrations evaluated at 6-months of age. Results: Overall, there was little evidence of an association between infant antibody concentrations and PCB measures during the pre- and early postnatal period. In addition, our results did not show specificity in terms of associations limited to a particular developmental period (e.g. pre- vs. postnatal), a particular antibody, or a particular PCB congener. Conclusions: At the PCB concentrations measured in this cohort, which are high relative to most human populations today, we did not detect an association between maternal or early postnatal PCB exposure and specific antibody responses at 6-months of age.

  20. RECENT DECLINES IN PAH, PCB, AND TOXAPHENE LEVELS IN THE NORTHERN GREAT LAKES AS DETERMINED FROM HIGH RESOLUTION SEDIMENT CORES. (R825151)

    EPA Science Inventory

    Sediment cores were collected from two sites in Grand Traverse Bay, Lake
    Michigan in May 1998, dated using 210Pb geochronology, and analyzed
    for polychlorinated biphenyl (PCB) congeners, polycyclic aromatic hydrocarbons
    (PAHs), and toxaphene. The extraor...

  1. Local contamination, and not feeding preferences, explains elevated PCB concentrations in Labrador ringed seals (Pusa hispida).

    PubMed

    Brown, Tanya M; Iverson, Sara J; Fisk, Aaron T; Macdonald, Robie W; Helbing, Caren C; Reimer, Ken J

    2015-05-15

    Polychlorinated biphenyls (PCBs) in high trophic level species typically reflect the contributions of myriad sources, such that source apportionment is rarely possible. The release of PCBs by a military radar station into Saglek Bay, Labrador contaminated the local marine food web. For instance, while heavier (higher chlorinated) PCB profiles in some ringed seals (Pusa hispida) were previously attributed to this local source, differences in feeding preferences among seals could not be ruled out as a contributing factor. Herein, similar fatty acid profiles between those seals with 'local' PCB profiles and those with 'long-range' or background profiles indicate little support for the possibility that differential feeding ecologies underlay the divergent PCB profiles. Ringed seals appeared to feed predominantly on zooplankton (Mysis oculata and Themisto libellula), followed by the dusky snailfish (Liparis gibbus), arctic cod (Boreogadus saida), and shorthorn sculpin (Myoxocephalus scorpius). Principal components analysis (PCA) and PCB homolog profiles illustrated the extent of contamination of the Saglek food web, which had very different (and much heavier) PCB profiles than those food web members contaminated by 'long-range' sources. Locally contaminated prey had PCB levels that were higher (2- to 544-fold) than prey contaminated by 'long-range' sources and exceeded wildlife consumption guidelines for PCBs. The application of multivariate analyses to two distinct datasets, including PCB congeners (n=50) and fatty acids (n=65), afforded the opportunity to clearly distinguish the contribution of locally-released PCBs to a ringed seal food web from those delivered via long-ranged transport. Results from the present study strongly suggest that habitat use rather than differences in prey selection is the primary mechanism explaining the divergent PCB patterns in Labrador ringed seals. PMID:25725460

  2. Bioaccumulation profiles of polychlorinated biphenyl congeners and organochlorine pesticides in Ganges River dolphins

    SciTech Connect

    Senthilkumar, K.; Kannan, K.; Sinha, R.K.; Tanabe, S.; Giesy, J.P.

    1999-07-01

    Isomer-specific concentrations of polychlorinated biphenyls (PCBs) including non-, mono-, and di-ortho-substituted congeners, DDT and its metabolites, hexachlorocyclohexane (HCH) isomers, chlordane compounds, and hexachlorobenzene (HCB) were determined in river dolphin blubber and prey fishes collected during 1993 through 1996 from the River Ganges in India. Concentrations of organochlorines were also measured in the milk and liver of dolphins, benthic invertebrates, and sediments. The DDTs and PCBs were the predominant compounds found in dolphin tissues and fish that comprise the diet of dolphins. Concentrations of DDTs and PCBs in the blubber of dolphins were in the range of 30 to 120 and 1.5 to 25 {micro}g/g, lipid weight, respectively. Penta- and hexachlorobiphenyls collectively accounted for 68 to 80% of the total PCB concentrations in river dolphins. Hexachlorobiphenyl congener 138 (2.2{prime}, 3,4,4{prime},5{prime}-) was the most abundant in dolphin blubber and prey fishes. The isomer/congener pattern of PCBs and organchlorine pesticides suggested that there is less metabolism due to cytochrome P450 enzymes in Ganges river dolphins than in marine or terrestrial mammals. The mean 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) estimated in river dolphin blubber was greater than those that can cause adverse effects in mink. Comparison of organochlorine concentrations in river dolphins with those of the values reported for samples analyzed during 1988 through 1992 suggested that the contamination by these compounds has increased in the River Ganges.

  3. Accumulation of polychlorinated biphenyl congeners from Lake Champlain sediments by Mysis relicta

    SciTech Connect

    Lester, D.C.; McIntosh, A. . Vermont Water Resources and Lake Studies Center)

    1994-11-01

    Polychlorinated biphenyl (PCB) levels in lake trout (Salvelinus namaycush) from Lake Champlain often exceed the F.D.A. tolerance level of 2 [mu]g/g (wet weight). Of added concern are recent studies that suggest a relationship between the dioxin-like properties of non-ortho-substituted PCB congeners and impaired lake trout egg hatchability. Dietary accumulation of PCBs is thought to be an important exposure route for fish. The epibenthic freshwater shrimp Mysis relicta is an integral part of the benthic and pelagic food web in lake Champlain and may act as a link between PCBs in sediments and lake trout. Previous investigations have shown that diurnal migrations of mysids enhance the movement and distribution of toxic contaminants, effectively coupling the benthic and pelagic zones. The objective of this research was to examine the role contaminated sediments play in the transfer of PCBs to mysids. Bioaccumulation was assessed by exposing mysids to such sediments in two ways: (a) with organisms screened from sediments; and (b) with organisms in direct contact with sediments. Accumulation of PCBs over the course of the 24-day exposure period was examined on the following days: 0, 3, 6, 12, 21, and 24. Eighty-nine individual PCB congeners were measured in tissue and sediment. Mysids in direct contact with sediments accumulated significantly higher levels of PCBs than did organisms screened from sediments. Mysids accumulated substantial levels of PCBs, suggesting they may play an important part in the transfer of PCBs from sediments into the Lake Champlain food web. It is clear from this research that sediments can play a critical role in the accumulation of PCBs by mysids.

  4. BIOACCUMULATION OF PCB CONGENERS BY BLUE MUSSELS DEPLOYED IN NEW BEDFORD HARBOR, MA

    EPA Science Inventory

    Blue mussels (Mytilus edulis) were deployed to monitor the levels of bioavailable contaminants during a pilot dredging project in New Bedford Harbor (NBH), Massachusetts. issolved and particulate seawater samples also were collected periodically during these deployments. olychlor...

  5. The Mass Spectrometric Ortho Effect Studied for All 209 PCB Congeners

    EPA Science Inventory

    A method for the determination of polychlorinated biphenyls (PCBs) in caulk was developed; with application to a set of caulk and window glazing material samples. This method was evaluated by analyzing a combination of 47 samples of caulk, glazing materials, and including quality...

  6. PARTITIONING, DESORPTION, AND DECHLORINATION OF A PCB CONGENER IN SEDIMENT SLURRY SUPERNATANTS

    EPA Science Inventory

    Partitioning and desorption played specific roles in the dechlorination of 2-chlorobiphenyl (2-ClBP) in sediment slurry supernatants, which are suspensions of disssolved organic matter(DOM). In short-term experiments, the partition coefficient (Kp) was related to the a...

  7. Polychlorinated biphenyl (PCB) congeners in Mussel and other mollusc from Da Chen Island, East China Sea

    SciTech Connect

    Chu, S.G.; Xi, Z.Q.; Xu, X.B

    1995-11-01

    Polychlorinated biphenyls (PCBs) are among the most persistent and toxic pollutants in environment. Determination of these contaminants in fish, shellfish and other mollusc is very important, not only because these aquatics are important food for mankind, but also because they can bioconcentrate contaminants preferentially in their adipose tissue, and serve as biomarker of the aquatic pollution. Mussels and oysters have been widely used to monitor the pollution in the coastal environment. The aim of the study was to investigate the concentrations and the main source of PCBs in mussels and other mollusca from the coastal areas of East China Sea. 10 refs., 3 figs., 2 tabs.

  8. PCB Congener Sorption To Carbonaceous Sediment Components: Macroscopic Comparison And Characterization Of Sorption Kinetics And Mechanism

    EPA Science Inventory

    Sorption of polychlorinated biphenyls (PCBs) to sediment is a key process in determining their mobility, bioavailability, and chemical decomposition in aquatic environments. In order to examine the validity of currently used interpretation approaches for PCBs sorption, comparati...

  9. Organochlorine pesticides and polychlorinated biphenyl congeners in lanner Falco biarmicus feldeggli Schlegel chicks and lanner prey in Sicily, Italy.

    PubMed

    Movalli, Paola; Lo Valvo, Mario; Pereira, M Glória; Osborn, Daniel

    2008-09-01

    This paper reports on research conducted to elucidate the risk posed to the Sicilian population of the endangered lanner falcon Falco biarmicus feldeggii Schlegel by organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs), as part of a wider study on contaminant risk to the lanner. Seventeen lanner nest sites were studied in northern and central Sicily. Sampling (in 2005) and analysis were carried out for selected OC pesticides and PCB congeners in lanner chick blood (15 chicks from 6 nest sites) and in two of the main lanner prey species, magpie Pica pica (36 individuals from 6 lanner nest sites) and rock dove Columba livia (10 individuals from 2 lanner nest sites). No OC and PCB residues were found in lanner chick blood above the detection limits, except for one solitary congener PCB153 (21.8 ng g(-1) wet weight), suggesting that these contaminants do not pose a significant risk to lanner chicks in the study area. Magpie and dove appeared mostly free of contamination with OC pesticides, though contamination levels were significantly higher in magpie than in dove. The presence of exceptional DDE and HEOD values in approximately 8% of the P. pica sample, and one P. pica sample showing recent DDT contamination, may indicate a local OC pesticide hazard to some lanner. Future research to further elucidate the contaminant risk to lanner in Sicily is suggested. PMID:18833798

  10. Examination of the estrogenicity of 2,4,6,2',6'-pentachlorobiphenyl (PCB 104), its hydroxylated metabolite 2,4,6,2',6'-pentachloro-4-biphenylol (HO-PCB 104), and a further chlorinated derivative, 2,4,6,2',4',6'-hexachlorobiphenyl (PCB 155).

    PubMed Central

    Fielden, M R; Chen, I; Chittim, B; Safe, S H; Zacharewski, T R

    1997-01-01

    Several studies have reported that polychlorinated biphenyls (PCBs) exhibit estrogenic activity; however, it is not clear if these responses are associated with the polychlorinated hydrocarbon or its hydroxylated metabolite. In order to further test this hypothesis, a battery of in vitro and in vivo assays were used to investigate the estrogenic and antiestrogenic activities of 2,4,6,2',6'-pentachlorobiphenyl (PCB 104), its para-hydroxylated derivative 2,4,6,2',6'-pentachloro-4-biphenylol (HO-PCB 104), and its para-chlorinated derivative 2,4,6,2',4',6'-hexachlorobiphenyl (PCB 155). PCB 104 was found to 1) compete with tritiated 17beta-estradiol (E2) for binding to the mouse uterine estrogen receptor (ER); 2) induce gene expression in MCF-7 human breast cancer cells transiently transfected with the Gal4-human ER chimeric construct (Gal4-HEGO) and the Gal4-regulated luciferase reporter gene (17m5-G-Luc); and 3) increase MCF-7 cell proliferation in a dose-dependent manner. HO-PCB 104 exhibited greater estrogenic activity than PCB 104 in the in vitro assays examined. However, gas chromatographic-mass spectrophotometric analysis of extracts prepared from MCF-7 cells incubated with PCB 104 failed to detect the presence of the expected major metabolite HO-PCB 104. The estrogenic activity of the para-chlorinated derivative, PCB 155, was minimal compared to PCB 104 and HO-PCB 104, but it did exhibit significant antiestrogenic activity following co-treatment with 1 nM E2. Co-treatment of PCB 104 with 1 nM E2 had no effect on reporter gene expression compared to E2 alone, while 10 microM HO-PCB 104 exhibited additivity with 1 nM E2. At a dose of 202 mg/kg,PCB 104 increased uterine wet weight in ovariectomized CD-1 mice and induced vaginal epithelial cell cornification at 202, 16, and 1.7 mg/kg in a dose-dependent manner. These studies demonstrate that in addition to the hydroxylated metabolites, selected parent PCB congeners may also exhibit estrogenic and antiestrogenic

  11. Isomer-specific accumulation and toxic assessment of polychlorinated biphenyls, including coplanar congeners, in cetaceans from the North Pacific and Asian coastal waters.

    PubMed

    Minh, T B; Nakata, H; Watanabe, M; Tanabe, S; Miyazaki, N; Jefferson, T A; Prudente, M; Subramanian, A

    2000-10-01

    To elucidate the global distribution and toxicological impacts of polychlorinated biphenyls (PCBs) on cetaceans, the present study determined the concentrations of individual PCB congeners, including toxic non-ortho (IUPAC Nos. 77, 126, 169) and mono-ortho (IUPAC Nos. 105, 118, 156) coplanar congeners, in the blubber of 10 species of adult male odontocetes collected from several locations in the North Pacific Ocean and along coastal waters of Japan, Hong Kong, the Philippines, and India during 1985-1997. Total PCB concentrations in cetaceans from temperate and cold waters were higher than those in cetaceans from tropical regions. Residue levels were found to be the highest in Fraser's dolphins collected off Kii Peninsula, Japan, and hump-backed dolphins from Hong Kong, reflecting serious marine pollution by PCBs in industrialized Asian countries. Penta- and hexa-chlorobiphenyls were the predominant PCB congeners, accounting for about 70% of the total PCBs. 2,3,7,8-Tetrachlorodibenzo-p-dioxin equivalents (TEQs) of non- and mono-ortho coplanar PCBs in the blubber of cetaceans ranged from 36 (in spinner dolphins from the Philippines) to 510 pg/g wet weight (in hump-backed dolphins from Hong Kong). Toxic evaluation of coplanar PCBs using the TEQ concept indicates an greater impact on cetaceans from mid-latitudes. Toxicity contribution of mono-ortho congener IUPAC 118 was prominent in species from high latitude oceans, such as the Bering Sea and the North Pacific, whereas non-ortho congener IUPAC 126 accounted for the highest contribution in cetaceans from lower latitude regions, such as the Philippines and India. The estimated TEQ concentrations in the blubber of some cetacean species, such as northern right whale dolphin and Pacific white-sided dolphin from the northern North Pacific, Dall's porpoise from the Japan Sea, striped dolphin off Sanriku and Fraser's dolphin off Kii Peninsula, Japan, hump-backed dolphin and finless porpoise from Hong Kong, exceeded the

  12. Acute alteration of cardiac ECG, action potential, I{sub Kr} and the human ether-a-go-go-related gene (hERG) K{sup +} channel by PCB 126 and PCB 77

    SciTech Connect

    Park, Mi-Hyeong; Park, Won Sun; Jo, Su-Hyun

    2012-07-01

    Polychlorinated biphenyls (PCBs) have been known as serious persistent organic pollutants (POPs), causing developmental delays and motor dysfunction. We have investigated the effects of two PCB congeners, 3,3′,4,4′-tetrachlorobiphenyl (PCB 77) and 3,3′,4,4′,5-pentachlorobiphenyl (PCB 126) on ECG, action potential, and the rapidly activating delayed rectifier K{sup +} current (I{sub Kr}) of guinea pigs' hearts, and hERG K{sup +} current expressed in Xenopus oocytes. PCB 126 shortened the corrected QT interval (QTc) of ECG and decreased the action potential duration at 90% (APD{sub 90}), and 50% of repolarization (APD{sub 50}) (P < 0.05) without changing the action potential duration at 20% (APD{sub 20}). PCB 77 decreased APD{sub 20} (P < 0.05) without affecting QTc, APD{sub 90}, and APD{sub 50}. The PCB 126 increased the I{sub Kr} in guinea-pig ventricular myocytes held at 36 °C and hERG K{sup +} current amplitude at the end of the voltage steps in voltage-dependent mode (P < 0.05); however, PCB 77 did not change the hERG K{sup +} current amplitude. The PCB 77 increased the diastolic Ca{sup 2+} and decreased Ca{sup 2+} transient amplitude (P < 0.05), however PCB 126 did not change. The results suggest that PCB 126 shortened the QTc and decreased the APD{sub 90} possibly by increasing I{sub Kr}, while PCB 77 decreased the APD{sub 20} possibly by other modulation related with intracellular Ca{sup 2+}. The present data indicate that the environmental toxicants, PCBs, can acutely affect cardiac electrophysiology including ECG, action potential, intracellular Ca{sup 2+}, and channel activity, resulting in toxic effects on the cardiac function in view of the possible accumulation of the PCBs in human body. -- Highlights: ► PCBs are known as serious environmental pollutants and developmental disruptors. ► PCB 126 shortened QT interval of ECG and action potential duration. ► PCB 126 increased human ether-a-go-go-related K{sup +} current and I{sub Kr}. ► PCB

  13. Levels, congener profile and inventory of polychlorinated biphenyls in sediment from the Songhua River in the vicinity of cement plant, China: a case study.

    PubMed

    Cui, Song; Fu, Qiang; Li, Yi-Fan; Li, Wen-Long; Li, Tian-Xiao; Wang, Min; Xing, Zhen-Xiang; Zhang, Lu-Ji

    2016-08-01

    This study investigated the contamination levels, homologue, and congener profiles and evaluated the residue inventory of polychlorinated biphenyls (PCBs) in sediment of the Songhua River in the vicinity of cement plant. The total concentration of detected 35 PCB congeners ranged from 1.12 to 2.19 ng/g dry weight (dw) in sediment, with a mean value of 1.56 ng/g dw, and the concentration of PCBs decreased in the following order: the downstream > cement plant > upstream. The results of total organic carbon (TOC)-normalized PCB concentrations indicate that the sediments have low potential ecological risk in this area. The study results on homologue and congener of PCBs show that the emissions from cement production could be the major sources of PCBs in sediment, and the low-chlorinated PCBs will be exchanged among air, water, and sediment with increasing temperature during summer and flow to downstream with water during the wet season. The spatial density and total burden of PCBs in the surface sediments were 17.2 ng/cm(2) and 1.2 kg, respectively. To our knowledge, this study is the first to explore the pollution characteristics of unintentionally produced PCB emissions from cement industry by means of monitoring sediment samples. PMID:27146527

  14. Can polychlorinated biphenyl (PCB) signatures and enantiomer fractions be used for source identification and to age date occupational exposure?

    PubMed

    Megson, David; Focant, Jean-Françios; Patterson, Donald G; Robson, Matthew; Lohan, Maeve C; Worsfold, Paul J; Comber, Sean; Kalin, Robert; Reiner, Eric; O'Sullivan, Gwen

    2015-08-01

    Detailed polychlorinated biphenyl (PCB) signatures and chiral Enantiomer Fractions (EFs) of CB-95, CB-136 and CB-149 were measured for 30 workers at a transformer dismantling plant. This was undertaken to identify sources of exposure and investigate changes to the PCB signature and EFs over different exposure periods. Approximately 1.5 g of serum was extracted and PCB signatures were created through analysis by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS) and EFs calculated following analysis by gas chromatography with high resolution mass spectrometry (GC-HRMS). A total of 84 PCBs were identified in the serum samples with concentrations of the 7 indicator PCBs ranging from 11-350 ng g(-1) of serum (1.2-39 μg g(-1) lipid). The PCB signatures were interpreted using principal component analysis (PCA) which was able to distinguish workers with background or recent minimal exposure from those with prolonged occupational exposure. Occupationally exposed individuals had a similar PCB profile to Aroclor A1260. However, individuals with prolonged exposure had depleted proportions of several PCB congeners that are susceptible to metabolism (CB-95, CB-101 and CB-151) and elevated proportions of PCBs that are resistant to metabolism (CB-74, CB-153, CB-138 and CB-180). The results also identified a third group of workers with elevated proportions of CB-28, CB-60, CB-66, CB-74, CB-105 and CB-118 who appeared to have been exposed to an additional source of PCBs. The results show near complete removal of the CB-95 E2 enantiomer in some samples, indicating that bioselective metabolism or preferential excretion of one enantiomer occurs in humans. By considering PCB concentrations along with detailed congener specific signatures it was possible to identify different exposure sources, and gain an insight into both the magnitude and duration of exposure. PMID:25916940

  15. Effects of thiol antioxidants on the atropselective oxidation of 2,2',3,3',6,6'-hexachlorobiphenyl (PCB 136) by rat liver microsomes.

    PubMed

    Wu, Xianai; Lehmler, Hans-Joachim

    2016-02-01

    Chiral polychlorinated biphenyl (PCB) congeners, such as PCB 136, are atropselectively metabolized to various hydroxylated PCB metabolites (HO-PCBs). The present study investigates the effect of two thiol antioxidants, glutathione and N-acetyl-cysteine (NAC), on profiles and chiral signatures of PCB 136 and its HO-PCB metabolites in rat liver microsomal incubations. Liver microsomes prepared from rats pretreated with phenobarbital were incubated with PCB 136 (5 μM) in the presence of the respective antioxidant (0-10 mM), and levels and chiral signatures of PCB 136 and its HO-PCB metabolites were determined. Three metabolites, 5-136 (2,2',3,3',6,6'-hexachlorobiphenyl-5-ol), 4-136 (2,2',3,3',6,6'-hexachlorobiphenyl-4-ol), and 4,5-136 (2,2',3,3',6,6'-hexachlorobiphenyl-4,5-diol), were detected in all incubations, with 5-136 being the major metabolite. Compared to microsomal incubations without antioxidant, levels of 4,5-136 increased with increasing antioxidant concentration, whereas levels of PCB 136 and both mono-HO-PCBs were not affected by the presence of either antioxidant. PCB 136, 4-136, and 5-136 displayed significant atropisomeric enrichment; however, the direction and extent of the atropisomeric enrichment was not altered in the presence of an antioxidant. Because 4,5-136 can either be conjugated to a sulfate or glucuronide metabolite that is readily excreted or further oxidized a potentially toxic PCB 136 quinone, the effect of both thiol antioxidants on 4,5-136 formation suggests that disruptions of glutathione homeostasis may alter the balance between both metabolic pathways and, thus, PCB 136 toxicity in vivo. PMID:26155892

  16. Subchronic inhalation exposure study of an airborne polychlorinated biphenyl mixture resembling the Chicago ambient air congener profile.

    PubMed

    Hu, Xin; Adamcakova-Dodd, Andrea; Lehmler, Hans-Joachim; Hu, Dingfei; Hornbuckle, Keri; Thorne, Peter S

    2012-09-01

    Although inhalation of atmospheric polychlorinated biphenyls (PCBs) is the most universal exposure route and has become a substantial concern in urban areas, research is lacking to determine the body burden of inhaled PCBs and consequent health effects. To reflect the Chicago airshed environment and mimic the PCB profile in Chicago air, we generated vapors from a Chicago air mixture (CAM). Sprague-Dawley rats were exposed to the CAM vapor for 1.6 h/day via nose-only inhalation for 4 weeks, 520 ± 10 μg/m(3). Congener-specific quantification in tissue and air samples was performed by gas chromatography-tandem mass spectrometry (GC/MS/MS). In contrast to the lower-chlorinated congener-enriched vapor, body tissues mainly contained tri- to hexachlorobiphenyls. Congener profiles varied between vapor and tissues and among different organs. The toxic equivalence (TEQ) and neurotoxic equivalence (NEQ) were also investigated for tissue distribution. We evaluated a variety of end points to catalogue the effects of long-term inhalation exposure, including immune responses, enzyme induction, cellular toxicity, and histopathologic abnormalities. Glutathione oxidized/reduced ratio (GSSG/GSH) was increased in the blood of exposed animals, accompanied by elevation of hematocrit. This study demonstrated that inhalation contributed to the body burden of mostly tri- to hexachlorobiphenyls and produced a distinct profile of congeners in tissue, yet minimal toxicity was found at this exposure dose, estimated at 134 μg/rat. PMID:22846166

  17. Evaluation of PCB sources and releases for identifying priorities to reduce PCBs in Washington State (USA).

    PubMed

    Davies, Holly; Delistraty, Damon

    2016-02-01

    Polychlorinated biphenyls (PCBs) are ubiquitously distributed in the environment and produce multiple adverse effects in humans and wildlife. As a result, the purpose of our study was to characterize PCB sources in anthropogenic materials and releases to the environment in Washington State (USA) in order to formulate recommendations to reduce PCB exposures. Methods included review of relevant publications (e.g., open literature, industry studies and reports, federal and state government databases), scaling of PCB sources from national or county estimates to state estimates, and communication with industry associations and private and public utilities. Recognizing high associated uncertainty due to incomplete data, we strived to provide central tendency estimates for PCB sources. In terms of mass (high to low), PCB sources include lamp ballasts, caulk, small capacitors, large capacitors, and transformers. For perspective, these sources (200,000-500,000 kg) overwhelm PCBs estimated to reside in the Puget Sound ecosystem (1500 kg). Annual releases of PCBs to the environment (high to low) are attributed to lamp ballasts (400-1500 kg), inadvertent generation by industrial processes (900 kg), caulk (160 kg), small capacitors (3-150 kg), large capacitors (10-80 kg), pigments and dyes (0.02-31 kg), and transformers (<2 kg). Recommendations to characterize the extent of PCB distribution and decrease exposures include assessment of PCBs in buildings (e.g., schools) and replacement of these materials, development of Best Management Practices (BMPs) to contain PCBs, reduction of inadvertent generation of PCBs in consumer products, expansion of environmental monitoring and public education, and research to identify specific PCB congener profiles in human tissues. PMID:26071980

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

    SciTech Connect

    Cocchi, Daniela; Tulipano, Giovanni; Colciago, Alessandra; Sibilia, Valeria; Pagani, Francesca; Vigano, Daniela; Rubino, Tiziana; Parolaro, Daniela; Bonfanti, Patrizia; Colombo, Anita; Celotti, Fabio

    2009-06-01

    Polychlorinated biphenyls (PCBs) are pollutants detected in animal tissues and breast milk. The experiments described in the present paper were aimed at evaluating whether the four PCB congeners most abundant in animal tissues (PCB-138, -153, -180 and -126), administered since fetal life till weaning, can induce long-term alterations of GH-axis activity and bone mass in the adult rat. We measured PCB accumulation in rat brain and liver, somatic growth, pituitary GH expression and plasma hormone concentrations at different ages. Finally, we studied hypothalamic somatostatin expression and bone structure in adulthood, following long-term PCB exposure. Dams were treated during pregnancy from GD15 to GD19 and during breast-feeding. A constant reduction of the growth rate in both male and female offspring from weaning to adulthood was observed in exposed animals. Long-lasting alterations on hypothalamic-pituitary GH axis were indeed observed in PCB-exposed rats in adulthood: increased somatostatin expression in hypothalamic periventricular nucleus (both males and females) and lateral arcuate nucleus (males, only) and decreased GH mRNA levels in the pituitary of male rats. Plasma IGF-1 levels were higher in PCB-exposed male and female animals as compared with controls at weaning and tended to be higher at PN60. Plasma testosterone and thyroid hormone concentrations were not significantly affected by exposure to PCBs. In adulthood, PCBs caused a significant reduction of bone mineral content and cortical bone thickness of tibiae in male rat joint to increased width of the epiphyseal cartilage disk. In conclusion, the developmental exposure to the four selected PCB compounds used in the present study induced far-reaching effects in the adult offspring, the male rats appearing more sensitive than females.

  19. Chemical and microbiological characterization of an aged PCB-contaminated soil.

    PubMed

    Stella, T; Covino, S; Burianová, E; Filipová, A; Křesinová, Z; Voříšková, J; Větrovský, T; Baldrian, P; Cajthaml, T

    2015-11-15

    This study was aimed at complex characterization of three soil samples (bulk soil, topsoil and rhizosphere soil) from a site historically contaminated with polychlorinated biphenyls (PCB). The bulk soil was the most highly contaminated, with a PCB concentration of 705.95 mg kg(-1), while the rhizosphere soil was the least contaminated (169.36 mg kg(-1)). PCB degradation intermediates, namely chlorobenzoic acids (CBAs), were detected in all the soil samples, suggesting the occurrence of microbial transformation processes over time. The higher content of organic carbon in the topsoil and rhizosphere soil than in the bulk soil could be linked to the reduced bioaccessibility (bioavailability) of these chlorinated pollutants. However, different proportions of the PCB congener contents and different bioaccessibility of the PCB homologues indicate microbial biotransformation of the compounds. The higher content of organic carbon probably also promoted the growth of microorganisms, as revealed by phospholipid fatty acid (PFLA) quantification. Tag-encoded pyrosequencing analysis showed that the bacterial community structure was significantly similar among the three soils and was predominated by Proteobacteria (44-48%) in all cases. Moreover, analysis at lower taxonomic levels pointed to the presence of genera (Sphingomonas, Bulkholderia, Arthrobacter, Bacillus) including members with reported PCB removal abilities. The fungal community was mostly represented by Basidiomycota and Ascomycota, which accounted for >80% of all the sequences detected in the three soils. Fungal taxa with biodegradation potential (Paxillus, Cryptococcus, Phoma, Mortierella) were also found. These results highlight the potential of the indigenous consortia present at the site as a starting point for PCB bioremediation processes. PMID:26156136

  20. PCB cycling in marine plankton

    SciTech Connect

    Ashizawa, D.; Brownawell, B.; Fisher, N.

    1995-12-31

    Ecosystem-scale models of contaminant bioaccumulation and toxicity are often sensitive to quantification of uptake and trophic transfer at the base of aquatic food chains. Significant uncertainty remains in assessing the rates and routes of transfer of hydrophobic contaminants by phytoplankton and zooplankton. Using radio-labeled 2,2{prime},4,4{prime}-tetrachlorobiphenyl (PCB), the authors have conducted experiments to measure the transfer of PCB from seawater to phytoplankton to copepods. Uptake, equilibration, and release of PCB onto/from algal cells were found to be rapid and not appreciably affected by the algal growth phase. Initial experiments indicate that when PCB-contaminated diatoms were fed to calanoid copepods, the assimilation efficiencies in the grazers ranged from 30--50%. Ongoing experiments are investigating this process further and quantitatively comparing copepod uptake of PCB from food and from the dissolved phase. These parameters of uptake and release are essential in the development and application of contaminant bioaccumulation models for marine and aquatic food chains.

  1. Polychlorinated biphenyl (PCBs) in rice grains and straw; risk surveillance, congener specific analysis, distribution and source apportionment from selected districts of Punjab Province, Pakistan.

    PubMed

    Mumtaz, Mehvish; Mehmood, Andleeb; Qadir, Abdul; Mahmood, Adeel; Malik, Riffat Naseem; Sabir, Arshed Makhdoom; Li, Jun; Zhang, Gan

    2016-02-01

    The current study presents health risk surveillance by investigating the levels of polychlorinated biphenyls (PCBs) in rice (Oryza sativa L.) grains and rice straw. Samples were collected from four districts (Okara, Sahiwal, Lahore and Sheikhpura) of Punjab Province, Pakistan for congener specific analysis of PCBs, and to observe the spatial distribution pattern and point sources. Level of Σ30 PCB (ng g(-1)) in rice grains and rice straw ranged from 4.31 to 29.68 and 6.11-25.35, respectively. Tetra-CBs were found predominant in rice straw (49%) and grains (38%) over other PCB homologs. No significant variation (P>0.005) was observed for most of the screened PCBs congeners except, PCB-66, -77, -60, -101, -74, -138, -153 and -105 in rice grains and PCB-66 in rice straw. Reported toxicity equivalency (TEQ) values for dioxin like PCBs in rice grains were found lower than the previously published reports from Asian countries, however higher TEQ values are reported for rice straw in this study. Health was found at risk of cancer among one in million by consumption of the study area food stuffs, though no considerable carcinogenic risks to human health was found. PMID:26613515

  2. Dietary Selenium as a Modulator of PCB 126–Induced Hepatotoxicity in Male Sprague-Dawley Rats

    PubMed Central

    Lai, Ian K.; Chai, Yingtao; Simmons, Donald; Watson, Walter H.; Tan, Rommel; Haschek, Wanda M.; Wang, Kai; Wang, Bingxuan; Ludewig, Gabriele; Robertson, Larry W.

    2011-01-01

    Homeostasis of selenium (Se), a critical antioxidant incorporated into amino acids and enzymes, is disrupted by exposure to aryl hydrocarbon receptor (AhR) agonists. Here we examined the importance of dietary Se in preventing the toxicity of the most toxic polychlorinated biphenyl congener, 3,3′,4,4′,5-pentachlorobiphenyl (PCB 126), a potent AhR agonist. Male Sprague-Dawley rats were fed a modified AIN-93 diet with differing dietary Se levels (0.02, 0.2, and 2 ppm). Following 3 weeks of acclimatization, rats from each dietary group were given a single ip injection of corn oil (vehicle), 0.2, 1, or 5 μmol/kg body weight PCB 126, followed 2 weeks later by euthanasia. PCB exposure caused dose-dependent increases in liver weight and at the highest PCB 126 dose decreases in whole body weight gains. Hepatic cytochrome P-450 (CYP1A1) activity was significantly increased even at the lowest dose of PCB 126, indicating potent AhR activation. PCB exposure diminished hepatic Se levels in a dose-dependent manner, and this was accompanied by diminished Se-dependent glutathione peroxidase activity. Both these effects were partially mitigated by Se supplementation. Conversely, thioredoxin (Trx) reductase activity and Trx oxidation state, although significantly diminished in the lowest dietary Se groups, were not affected by PCB exposure. In addition, PCB 126–induced changes in hepatic copper, iron, manganese, and zinc were observed. These results demonstrate that supplemental dietary Se was not able to completely prevent the toxicity caused by PCB 126 but was able to increase moderately the levels of several key antioxidants, thereby maintaining them roughly at normal levels. PMID:21865291

  3. Organochlorine pesticides and polychlorinated biphenyl congeners in wild terrestrial mammals from Croatia: Interspecies comparison of residue levels and compositions.

    PubMed

    Herceg Romanić, Snježana; Klinčić, Darija; Kljaković-Gašpić, Zorana; Kusak, Josip; Reljić, Slaven; Huber, Đuro

    2015-10-01

    In this pilot study, we investigated levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in the adipose tissues of two free-ranging terrestrial carnivores from Croatia sampled in 2010 and 2011: the brown bear (Ursus arctos; N=32) and the grey wolf (Canis lupus; N=29). Concentrations of ∑OCPs and ΣPCBs ranged from 0.45 to 4.09 ng g(-1) lipid mass (lm) and from 0.93 to 8.52 ng g(-1) lm in brown bear, and from 1.18 to 5.67 ng g(-1) lm and 2.68 to 48.9 ng g(-1) lm in grey wolf adipose tissues, respectively. PCBs were dominant accounting for over 72% of total analyzed persistent organic pollutants (POPs). The sum of six indicator non-dioxin-like PCBs (Σ6IndNDL PCBs) made up 60-93% and 58-85% of the total congener concentrations in brown bears and wolves, respectively. Although the levels of the measured parameters were significantly higher in grey wolves than in bears, the contaminant profiles of the two species were similar, with γ-HCH, HCB, β-HCH and DDE as major OCP contaminants, and PCB-153>PCB-180≈PCB-170>PCB-138 as the dominant congeners. The sum of hexachlorocyclohexanes (ΣHCHs) and 8 toxicologically relevant dioxin-like PCBs (Σ8ToxDL PCBs) was higher in the males than in the females of the brown bear. Concentrations of ΣDDTs, HCB, ΣOCP, ΣPCBs, Σ6IndNDL PCBs, and toxicologically relevant non-dioxin-like PCBs (ΣToxNDL PCBs) were significantly positively correlated with lipid content in the grey wolf. Concentrations of OCPs and PCBs in brown bears and wolves from Croatia were low and normal for large terrestrial mammals. PMID:26002287

  4. Aerobic and anaerobic PCB biodegradation in the environment

    SciTech Connect

    Abramowicz, D.A.

    1995-06-01

    Studies have identified two distinct biological processes capable of biotransforming polychlorinated biphenyls (PCBs): aerobic oxidative processes and anaerobic reductive processes. It is now known that these two complementary activities are occurring naturally in the environment. Anaerobic PCB dechlorination, responsible for the conversion of highly chlorinated PCBs to lightly chlorinated ortho-enriched congeners, has been documented extensively in the Hudson River and has been observed at many other sites throughout the world. The products from this anaerobic process are readily degradable by a wide range of aerobic bacteria, and it has now been shown that this process is occurring in surficial sediments in the Hudson River. The widespread anaerobic dechlorination of PCBs that has been observed in many river and marine sediments results in reduction of both the potential risk from and potential exposure to PCBs. The reductions in potential risk include reduced dioxin like toxicity and reduced carcinogenicity. The reduced PCB exposure realized upon dechlorination is manifested by reduced bioaccumulation in the food chain and by the increased anaerobic degradability of these products. 27 refs., 1 fig., 1 tab.

  5. Burial, incineration solve Alaskan PCB contamination

    SciTech Connect

    Ives, J.A. ); Young, D.T. )

    1989-10-01

    Polychlorinated biphenyl (PCB) remediation at Alaska's Swanson River has excavated more than 80,000 tons of PCB-contaminated soil and isolated it in bermed and lined stock-piles. In addition, incineration of other PCB-contaminated materials has been carried out safely. This article on the site reviews its history and part of its remediation approaches.

  6. PCB exposure in sea otters and harlequin ducks in relation to history of contamination by the Exxon Valdez oil spill.

    PubMed

    Ricca, Mark A; Keith Miles, A; Ballachey, Brenda E; Bodkin, James L; Esler, Daniel; Trust, Kimberly A

    2010-06-01

    Exposure to contaminants other than petroleum hydrocarbons could confound interpretation of Exxon Valdez oil spill effects on biota at Prince William Sound, Alaska. Hence, we investigated polychlorinated biphenyls (PCBs) in blood of sea otters and harlequin ducks sampled during 1998. PCB concentrations characterized by lower chlorinated congeners were highest in sea otters from the unoiled area, whereas concentrations were similar among harlequin ducks from the oiled and unoiled area. Blood enzymes often elevated by xenobiotics were not related to PCB concentrations in sea otters. Only sea otters from the unoiled area had estimated risk from PCBs, and PCB composition or concentrations did not correspond to reported lower measures of population performance in sea otters or harlequin ducks from the oiled area. PCBs probably did not influence limited sea otter or harlequin duck recovery in the oiled area a decade after the spill. PMID:20132952

  7. [Analysis of toxaphene and its eight congeners in sediment and fish tissue by gas chromatography-negative ion mass spectrometry].

    PubMed

    Lao, Wenjian

    2013-07-01

    Toxaphene quantification incorporating gas chromatography/negative chemical ionization mass spectrometry (GC/NCI-MS) offers improved sensitivity and specificity. The U. S. Environmental Protection Agency (USEPA) recently released a GC/NCI-MS method (Method 8276) for the measurement of technical toxaphene and eight specific congeners (Hx-Sed, Hp-Sed, P26, P41, P40, P44, P50 and P62). However, there is still lack of a practical and complete analytical method including sample extraction, clean up, instrumental analysis, and data analysis. The goal of this work was to develop a ready-to-use method for the quantification of total toxaphene and the eight congeners. Sediment and salmon fish tissue were selected as sample matrices and extracted with methylene chloride using an accelerated solvent extraction system. The sample extracts were cleaned up with active copper powder or gel permeation chromatography, and finally silica/alumina combination column. Separation was performed on a DB-XLB column. GC/NCI-MS was operated under selected ion monitoring mode with an identical set of confirmation and quantitation ions for total toxaphene and the eight congeners. Oxygen reaction of polychlorinated biphenyls (PCB) was monitored by PCB204, an internal calibration standard, and the reaction level was kept below 1%. Average relative response factors were used in quantitation. Quantitation of total toxaphene employed the sum of all detectable (S/N > or = 3) 6-C1 to 10-Cl homolog peak areas, while the individual congeners were quantified followed the standard procedures for single analytes. Multi-point calibration solutions ranged from 0. 5 (5 for P62) to 500 microg/L for the individual congeners, and 50 to 500 microg/L for technical toxaphene, with the lowest calibration levels as lower limits of quantitation. Average congener recovery was (90.8 +/- 17.4)% (n =10) in spiked sediment with relative standard deviations of 5.4% - 12.8% (n =10), underscoring an excellently accurate and

  8. Potency of 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB 126), alone and in combination with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), to produce lake trout early life-stage mortality

    SciTech Connect

    Zabel, E.W.; Peterson, R.E.; Cook, P.M.

    1995-12-01

    Newly fertilized lake trout (Salvelinus namaycush) eggs were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB 126), or their combination, and sac fry mortality was used to determine toxic potencies. The toxic equivalency factor (TEF) for PCB 126 was 0.0030. The dose-response curve for the PCB 126/TCDD mixture based on TCDD toxic equivalents was not significantly different from that for TCDD alone, suggesting additivity between the two congeners in causing sac fry mortality.

  9. Population dynamics of dechlorinators and factors affecting the level and products of PCB dechlorination in sediments

    SciTech Connect

    Kim, J.S.; Sokol, R.C.; Liu, X.; Bethoney, C.M.; Rhee, G.Y.

    1996-12-31

    Microbial dechlorination of polychlorinated biphenyls (PCBs) often stops although a significant number of removable chlorines remain. To determine the reason for the cessation, we investigated the limitation of organic carbon, PCB bioavailability, and inhibition by metabolic products. Enrichment with carbon sources did not induce additional chlorination, indicating the plateau was not due to depletion of organic carbon. The bioavailability was not limiting, since a subcritical micelle concentration of the surfactant, which enhanced desorption without inhibiting dechlorinating microorganisms, failed to lower the plateau. Neither was it due to accumulation of metabolites, since no additional dechlorination was detected when plateau sediments were incubated with fresh medium. Similarly, dechlorination was not inhibited in freshly spiked sediment slurries. Dechlorination ended up at the same level with nearly identical congener profiles, regardless of treatment. These results indicate that cessation of dechlorination was due to the accumulation of daughter congeners, which cannot be used as electron acceptors by microbes. To determine whether the decreasing availability affected the microorganisms, we determined the population dynamics of dechlorinators using the most probable number technique. The growth dynamics of the dechlorinators mirrored the time course of dechlorination. It started when the population increased by two orders of magnitude. Once dechlorination stopped the dechlorinating population also began to decrease. When dechlorinators were inoculated into PCB-free sediments, the population decreased over time. The decrease of the population as dechlorination ceased confirms that the diminishing availability of congeners was the reason for the incomplete dechlorination. Recent findings have shown that a second phase of dechlorination of certain congeners can occur after a long lag. 45 refs., 8 figs.

  10. A dynamic and mechanistic model of PCB bioaccumulation in the European hake ( Merluccius merluccius)

    NASA Astrophysics Data System (ADS)

    Bodiguel, Xavier; Maury, Olivier; Mellon-Duval, Capucine; Roupsard, François; Le Guellec, Anne-Marie; Loizeau, Véronique

    2009-08-01

    Bioaccumulation is difficult to document because responses differ among chemical compounds, with environmental conditions, and physiological processes characteristic of each species. We use a mechanistic model, based on the Dynamic Energy Budget (DEB) theory, to take into account this complexity and study factors impacting accumulation of organic pollutants in fish through ontogeny. The bioaccumulation model proposed is a comprehensive approach that relates evolution of hake PCB contamination to physiological information about the fish, such as diet, metabolism, reserve and reproduction status. The species studied is the European hake ( Merluccius merluccius, L. 1758). The model is applied to study the total concentration and the lipid normalised concentration of 4 PCB congeners in male and female hakes from the Gulf of Lions (NW Mediterranean sea) and the Bay of Biscay (NE Atlantic ocean). Outputs of the model compare consistently to measurements over the life span of fish. Simulation results clearly demonstrate the relative effects of food contamination, growth and reproduction on the PCB bioaccumulation in hake. The same species living in different habitats and exposed to different PCB prey concentrations exhibit marked difference in the body accumulation of PCBs. At the adult stage, female hakes have a lower PCB concentration compared to males for a given length. We successfully simulated these sex-specific PCB concentrations by considering two mechanisms: a higher energy allocation to growth for females and a transfer of PCBs from the female to its eggs when allocating lipids from reserve to eggs. Finally, by its mechanistic description of physiological processes, the model is relevant for other species and sets the stage for a mechanistic understanding of toxicity and ecological effects of organic contaminants in marine organisms.

  11. Alterations in DRH and DRL performance in rats developmentally exposed to an environmental PCB mixture.

    PubMed

    Sable, Helen J K; Powers, Brian E; Wang, Victor C; Widholm, John J; Schantz, Susan L

    2006-01-01

    Schedule-controlled responding was examined in offspring of rats exposed to a PCB mixture formulated to mimic the PCB congener profile in fish from the Fox River in Green Bay, WI. Female rats were administered 0, 1, 3, or 6 mg/kg/day of the PCB mixture beginning four weeks prior to breeding until weaning on postnatal day 21. When offspring were approximately 235 days old, they were tested on three different schedules of a differential reinforcement of high rate (DRH) operant task (DRH 2:1, DRH 4:2, and DRH 8:4). DRH testing was followed by testing on the differential reinforcement of low rate (DRL) operant task in which rats had to inhibit responding until 15 s had elapsed (DRL 15) from the previous response in order to obtain a food reinforcer. After completion of DRL 15 testing, 3 days of extinction testing were conducted (DRL EXT) during which no reinforcers were delivered. Developmental exposure to the higher PCB doses resulted in shorter inter-response times (IRTs) and shorter response durations during DRH 8:4, which translated into a greater percentage of reinforced trials. For DRL 15, no significant exposure-related effects were observed on the number of responses or reinforcers earned, or the number or proportion of responses with long or short inter-response times during acquisition or steady state performance. However, during DRL EXT, rats developmentally exposed to the highest PCB dose responded more than controls, produced significantly more short IRT responses, and had a significantly lower proportion of long IRT responses. Overall, exposure to this PCB mixture resulted in increased responding which was suggestive of a deficit in inhibitory control. PMID:16930942

  12. PCB contamination in soils of the Pearl River Delta, South China: levels, sources, and potential risks.

    PubMed

    Zhang, Haibo; Luo, Yongming; Teng, Ying; Wan, Hongfu

    2013-08-01

    Polychlorinated biphenyls (PCBs) contamination in tropical and sub-tropical areas and the associated risks have attracted great concern. A total of 69 samples representing five distinct land types were collected to assess PCB concentrations in the Pearl River Delta (PRD), South China, including spatial distributions in soils of the area, the probable anthropogenic sources, and related potential risks. PCBs concentrations in soils of the PRD ranged from 0.3 to 202 ng g(-1). More severe PCBs contamination was presented in the western part than in the eastern part of the PRD region. The PCBs were dominated by low-chlorinated biphenyls; however, the proportion of higher-chlorinated biphenyls was elevated with the influence of industrial activities. Principal component analysis indicated that PCBs contamination in soils of the PRD region was mainly associated with 1#PCBs, while 2#PCB and e-waste emission in South China also accounted for it partly, especially to the industrial activity severely impacted areas. Toxic equivalent (TEQ) of the dioxin-like PCBs in the soils indicated that higher risk of PCB contamination was presented in the Dongjiang River Valley (55 ng TEQ kg(-1), on average) than in the Xijiang River Valley, and were mostly contributed by the congener of PCB126. PMID:23354616

  13. How much do PCB toxic equivalents account for PHAH toxicity in predatory birds?

    PubMed

    Pereira, M Glória; Murk, A J; Van den Berg, H; Walker, Lee A; Shore, Richard F

    2014-10-01

    Various diffuse polyhalogenated aromatic hydrocarbons (PHAHs) exert common toxicity through the aryl hydrocarbon receptor (AhR). Apex predators spatially and temporally integrate diffuse contamination and simultaneous exposure can cause additive toxicity. We investigated the extent to which PCBs, still amongst the most prevalent PHAHs accumulated by predators, accounted for total PHAH toxicity in raptors and fish eating birds from Britain. We analysed egg or liver extracts from six species and compared chemically determined ΣPCB-TEQs concentrations with total AhR-mediated toxicity determined using the chemical-activated luciferase gene expression bioassay (CALUX-TEQ). Dioxin-like PCB profiles in eggs and livers were dominated by congeners 118, 105 and 167. ΣPCB-TEQ and CALUX-TEQ concentrations were positively associated but not in a 1:1 relationship. ΣPCB-TEQ were broadly similar to CALUX-TEQ concentrations in eggs and livers with CALUX-TEQ concentrations >50-80 and 160-320 pg g(-1) lipid respectively, but were lower than CALUX-TEQ concentrations in less contaminated samples. PMID:25062280

  14. Clapper rails as indicators of mercury and PCB bioavailability in a Georgia saltmarsh system.

    PubMed

    Cumbee, J C; Gaines, K F; Mills, G L; Garvin, N; Stephens, W L; Novak, J M; Brisbin, I L

    2008-08-01

    Clapper rails (Rallus longirostris) were used as an indicator species of estuarine marsh habitat quality because of their strong site fidelity and predictable diet consisting of mostly benthic organisms. Mercury (Hg) and the polychlorinated biphenyl (PCB) Aroclor 1268 concentrations were determined for sediments, crabs, as well as clapper rail adults and chicks collected from salt marshes associated with the LCP Superfund site in Brunswick, Georgia. Home ranges were established for adult rails, and sediment and crab samples were taken from each individual's range. The study was designed to minimize the spatial variability associated with trophic transfer studies by choosing an endpoint species with a potentially small home range and specifically sampling its foraging range. The mean home range for clapper rails was 1.2 ha with a median of 0.28 ha. Concentrations of Hg and Aroclor 1268 were shown to increase with each trophic level. Transfer factors between media followed the same pattern for both contaminants with the highest between fiddler crabs and clapper rail liver. Hg and PCB transfer factors were similar between sediment to fiddler crab and fiddler crab to muscle, however the PCB transfer factor from fiddler crabs to liver was over twice as large as for Hg. PCB congener profiles did not significantly differ between media types. PMID:18389370

  15. Continuous coculture degradation of selected polychlorinated biphenyl congeners by Acinetobacter spp. in an aerobic reactor system

    SciTech Connect

    Adriaens, P.; Focht, D.D. )

    1990-07-01

    A coculture of two Acinetobacter spp. was applied to degrade polychlorinated biphenyls during a 42-day incubation study in a continuous aerobic fixed-bed reactor system, filled with polyurethane foam boards as support for bacterial biofilm development. The reactor was supplied with mineral medium containing 500 ppm sodium benzoate as a growth (primary) substrate, while the incoming airstream was saturated with biphenyl vapors to induce for PCB cometabolism in Acinetobacter sp. strain P6. The chlorobenzoates thus generated from 4,4{prime}-dichlorobiphenyl (4,4{prime}-DCBP), 3,4-dichlorobiphenyl (3,4-DCBP), and 3,3{prime},4,4{prime}-tetrachlorobiphenyl were further metabolized by Acinetobacter sp. strain 4-CB1. The chlorobenzoate metabolites, as well as ring-fission product ({lambda}{sub max} = 442 nm) from the PCB congeners, accounted for the degradation of 63% (2.8 mM) of the 4,4{prime}-DCBP, 100% (0.5 mM) of the 3,4-DCBP, and 32% (0.12 mM) of the 3,3{prime},4,4{prime}-TCBP, the biofilm responded with a concurrent higher release of chlorobenzoates and chloride through cosubstrate utilization.

  16. Specific non-coplanar PCB-mediated modulation of bottlenose dolphin and beluga whale phagocytosis upon in vitro exposure.

    PubMed

    Levin, Milton; Morsey, Brenda; Mori, Chiharu; Guise, Sylvain

    2004-10-01

    Contaminant-induced immunosuppression by organochlorines (OC), particularly polychlorinated biphenyls (PCBs), has been suspected as a cofactor in the deaths of thousands of marine mammals. One important innate defense mechanism is phagocytosis, the ability of cells to ingest extracellular macromolecules. The present study was aimed at characterizing the immunomodulatory potential of representative OCs on phagocytosis in bottlenose dolphins and beluga whales. The ability of peripheral blood leukocytes to engulf fluorescent microspheres was evaluated using flow cytometry. The immunomodulatory effects of three non-coplanar PCB congeners, 138, 153, and 180, one coplanar PCB, 169, and 2,3,7,8-TCDD and all possible mixtures (26) were tested upon in vitro exposure. In both species, all mixtures containing at least two non-coplanar PCBs significantly reduced both neutrophil and monocyte phagocytosis, with effects more marked in dolphins than in belugas. Coplanar OCs, on their own or when added to non-coplanar congeners, did not further modulate phagocytosis, suggesting an Ah receptor-independent mechanism. Concentration-response experiments with individual congeners further demonstrated a non-coplanar PCB-induced suppression of phagocytosis, while coplanar congeners produced no consistent effects. Our results suggest simple additive interactions of chemicals in a mixture. However, calculation of toxic equivalency (TEQs) failed to predict the experimentally induced immunomodulatory effects of OCs on dolphin and beluga phagocytosis, confirming the Ah receptor-independent nature of the effects on phagocytosis. Overall, our results suggest that non-AhR mechanisms may explain one facet of immunotoxicity (phagocytosis), something that is not captured using the TEQ approach. This is the first report demonstrating the immunomodulatory effects of OCs on dolphin and beluga phagocytosis, and the first overall demonstration of immunomodulatory effects on phagocytosis mediated

  17. Hepatic Metabolism Affects the Atropselective Disposition of 2,2′,3,3′,6,6′-Hexachlorobiphenyl (PCB 136) in Mice

    PubMed Central

    2015-01-01

    To understand the role of hepatic vs extrahepatic metabolism in the disposition of chiral PCBs, we studied the disposition of 2,2′,3,3′,6,6′-hexachlorobiphenyl (PCB 136) and its hydroxylated metabolites (HO-PCBs) in mice with defective hepatic metabolism due to the liver-specific deletion of cytochrome P450 oxidoreductase (KO mice). Female KO and congenic wild type (WT) mice were treated with racemic PCB 136, and levels and chiral signatures of PCB 136 and HO-PCBs were determined in tissues and excreta 3 days after PCB administration. PCB 136 tissue levels were higher in KO compared to WT mice. Feces was a major route of PCB metabolite excretion, with 2,2′,3,3′,6,6′-hexachlorobiphenyl-5-ol being the major metabolite recovered from feces. (+)-PCB 136, the second eluting PCB 136 atropisomers, was enriched in all tissues and excreta. The second eluting atropisomers of the HO-PCBs metabolites were enriched in blood and liver; 2,2′,3,3′,6,6′-hexachlorobiphenyl-5-ol in blood was an exception and displayed an enrichment of the first eluting atropisomers. Fecal HO-PCB levels and chiral signatures changed with time and differed between KO and WT mice, with larger HO-PCB enantiomeric fractions in WT compared to KO mice. Our results demonstrate that hepatic and, possibly, extrahepatic cytochrome P450 (P450) enzymes play a role in the disposition of PCBs. PMID:25420130

  18. Swimming against the PCB tide

    SciTech Connect

    Stone, R.

    1992-02-14

    Although no PCBs have been manufactured in the US and other industrialized countries for years, the chemicals are still very much with us; they are extremely long-lived. And only about 1% of the total PCBs produced have reached the oceans so far. PCBs and related organohalogens that have entered the oceans are making their way through the food chain into marine animals. As a result the animals are becoming more prone to a variety of ailments, including reproductive abnormalities and immune suppression that makes them more susceptible to disease. Unless something is done to prevent further contamination by organohalogens such as PCB, many species of ocean mammals might become extinct and some species of fish inedible. Several scientists officially launched a campaign to solicit funds for a 3-year research project aimed at determining just how serious PCB and other organohalogen problems are in the oceans.

  19. Time-Trends and Congener Profiles of PBDEs and PCBs in California Peregrine Falcons (Falco peregrinus)

    PubMed Central

    Park, June-Soo; Holden, Arthur; Chu, Vivian; Kim, Michele; Rhee, Alexandra; Patel, Puja; Shi, Yating; Linthicum, Janet; Walton, Brian J.; Mckeown, Karen; Jewell, Nicholas P.; Hooper, Kim

    2010-01-01

    High levels (µg/g lw) of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in peregrine falcon eggs from California (n = 90 eggs from 52 birds, 38 nest sites, collected 1986–2007, ΣPBDEs median = 4.53, range = 0.08–53.1). Over the past 22 years, PBDE levels more than tripled each decade in the eggs, whereas PCB levels had no significant changes. PBDE levels were highest in eggs from major California cities (“Big Cities”), whereas PCBs showed no difference across the regions. For PBDEs, Big City eggs had markedly different patterns from Coastal eggs:BDE-209 and the higher brominated PBDEs (hexa–nona) were dominant congeners in Big City eggs, while BDE-47 and -99 were dominant in Coastal eggs. In many of the birds that gave multiple eggs over time (“time series”), PBDE patterns changed over time: the high proportions of BDE-209 and higher brominated PBDEs (short half-lives) in young birds contrasted with increasingly higher proportions of BDE-153 (long half-life) and other lower brominated PBDEs as the birds aged. These data are consistent with metabolic debromination of BDE-209 (t1/2 = 1–2 weeks) to the lower brominated PBDEs, with accumulation over time of BDE-153 (t1/2 = 3–4 years). In contrast, PCB patterns showed no differences by locations, and did not change over time. Diet (prey birds) may explain the urban PBDE pattern, as the patterns in urban pigeons and peregrines were similar, with high proportions of BDE-209 and the higher-brominated PBDEs. Also, our prey data (feathers from peregrine nests) showed urban peregrines having a higher proportion (>2 fold) of granivorous/opportunistic birds (e.g., “introduced feral” pigeons, mourning doves, starlings) in their diet than coastal peregrines. In summary, these data indicate that BDE-209 exits consumer products as an environmental contaminant to be taken up by wildlife (particularly in urban locations), and undergoes metabolic debromination to the

  20. Time-trends and congener profiles of PBDEs and PCBs in California peregrine falcons (Falco peregrinus).

    PubMed

    Park, June-Soo; Holden, Arthur; Chu, Vivian; Kim, Michele; Rhee, Alexandra; Patel, Puja; Shi, Yating; Linthicum, Janet; Walton, Brian J; McKeown, Karen; Jewell, Nicholas P; Hooper, Kim

    2009-12-01

    High levels (microg/g lw) of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in peregrine falcon eggs from California (n = 90 eggs from 52 birds, 38 nest sites, collected 1986-2007, SigmaPBDEs median = 4.53, range = 0.08-53.1). Over the past 22 years, PBDE levels more than tripled each decade in the eggs, whereas PCB levels had no significant changes. PBDE levels were highest in eggs from major California cities ("Big Cities"), whereas PCBs showed no difference across the regions. For PBDEs, Big City eggs had markedly different patterns from Coastal eggs: BDE-209 and the higher brominated PBDEs (hexa-nona) were dominant congeners in Big City eggs, while BDE-47 and -99 were dominant in Coastal eggs. In many of the birds that gave multiple eggs over time ("time series"), PBDE patterns changed over time: the high proportions of BDE-209 and higher brominated PBDEs (short half-lives) in young birds contrasted with increasingly higher proportions of BDE-153 (long half-life) and other lower brominated PBDEs as the birds aged. These data are consistent with metabolic debromination of BDE-209 (t(1/2) = 1-2 weeks) to the lower brominated PBDEs, with accumulation over time of BDE-153 (t(1/2) = 3-4 years). In contrast, PCB patterns showed no differences by locations, and did not change over time. Diet (prey birds) may explain the urban PBDE pattern, as the patterns in urban pigeons and peregrines were similar, with high proportions of BDE-209 and the higher-brominated PBDEs. Also, our prey data (feathers from peregrine nests) showed urban peregrines having a higher proportion (>2 fold) of granivorous/opportunistic birds (e.g., "introduced feral" pigeons, mourning doves, starlings) in their diet than coastal peregrines. In summary, these data indicate that BDE-209 exits consumer products as an environmental contaminant to be taken up by wildlife (particularly in urban locations), and undergoes metabolic debromination to the banned lower

  1. Maternal transfer of contaminants: case study of the excretion of three polychlorinated biphenyl congeners and technical-grade endosulfan into eggs by white Leghorn chickens (Gallus domesticus).

    PubMed

    Bargar, T A; Scott, G I; Cobb, G P

    2001-01-01

    Reported avian maternal transfer rates of organochlorine contaminants range from 1% to as much as 20% of maternal body burdens. However, to our knowledge, no investigation of factors governing maternal transfer has been reported. Here, we report an investigation of maternal transfer of 2,3,3',4,4'-pentachlorinated biphenyl (PCB 105), 2,3,3',4,4',5-hexachlorinated biphenyl (PCB 156), 2,3,3',4,4',5,5'-heptachlorinated biphenyl (PCB 189), and technical-grade endosulfan into eggs by white leghorn chickens (Gallus domesticus). Two experiments were performed to evaluate individual chemical excretion into eggs when hens were injected with each chemical individually (experiment one) or with a mixture of all four chemicals (experiment two). Each hen was injected subcutaneously every 4 d during a 21-d period with 100 microliters of the dosing solution during both experiments. The mass of each chemical excreted into the egg was compared among eggs and with the mass injected into hens to determine the influence of chemical structure (experiment one) and interaction (experiment two) on maternal transfer of those chemicals into eggs. Maternal transfer of PCBs was inversely related to congener chlorination. The congener mass in eggs, as a percentage of the mass injected into hens, was 0.42% for PCB 189, 0.54% for PCB 156, and 0.61% for PCB 105. In experiment two, absolute excretion of only PCB 189 and alpha-endosulfan into eggs was affected by the presence of other chemicals. Excretion of PCB 189 (0.51%) and alpha-endosulfan (0.03%) increased and decreased, respectively, compared with when they were individually injected into hens during experiment one. Lastly, much less of the more metabolically susceptible endosulfan (0.04-0.12% of the mass injected) was excreted into the egg relative to PCBs, despite being injected into the hens at concentrations comparable with those of PCBs, suggesting, at least in avian species, lower maternal transfer of more metabolically susceptible

  2. Levels and distribution patterns of polychlorinated biphenyl congeners in surface sediments from Galicia coast (Northwestern, Spain) according to granulometric characteristics.

    PubMed

    Carro, N; García, I; Ignacio, M; Moureira, A

    2002-08-01

    In order to know distribution patterns of polychlorinated biphenyl congeners in the marine environment from Galida, PCBs n degrees 31, 28, 52, 101, 118, 153, 105, 138, 156 and 180 were isolated by Soxhlet extraction from three fractions of different particle size (<0.063 mm, 0.063-0.2 mm and >0.2 mm) in surface marine sediments; the quantification was performed using GC-MS and GC-ECD. Distribution of PCB congeners was shifted in favour of higher chlorinated compounds (CBs 138,153 and 180) and highly correlated to TOC content. In general, the finest fractions (<0.063 mm) of sediment presented the highest loadings of PCBs, only the sediment from As Pías zone exhibited the highest concentration of chlorinated congeners in the coarsest fraction. CB 52 concentration, slightly volatile compound, was related to water temperature. By means of multivariate techniques of data exploration as hierarchical duster analysis and principal components analysis, sediment samples from un-contaminated and slightly contaminated areas were clearly separated; groupings between samples from nearby zones appeared. PMID:12211452

  3. PCB (Polychlorinated Biphenyls) retrofill: Fact or fiction

    SciTech Connect

    Seifert, G.D.

    1990-01-01

    PCB transformers changes form the fire safety engineers friend to the environmental engineers worst nightmare, when it became apparent that PCB filled devices are a source of highly toxic chemicals when they are burned improperly. This concern, combined with new regulations, is prompting engineers worldwide to actively plan and design PCB replacements. The two most commonly used PCB mitigation methods are retrofill and retrofit. This report will address retrofill only and is directed toward environmental concerns, facility interfaces, outage requirements, and application questions. This information is offered to help engineers make informed decisions regarding the best way to replace PCB transformers. This overview also addresses whether PCB retrofill is a viable fact'' or is it fiction'' without merit. 3 figs.

  4. PCB Analysis Plan for Tank Archive Samples

    SciTech Connect

    NGUYEN, D.M.

    2001-03-22

    This analysis plan specifies laboratory analysis, quality assurance/quality control (QA/QC), and data reporting requirements for analyzing polychlorinated biphenyls (PCB) concentrations in archive samples. Tank waste archive samples that are planned for PCB analysis are identified in Nguyen 2001. The tanks and samples are summarized in Table 1-1. The analytical data will be used to establish a PCB baseline inventory in Hanford tanks.

  5. PCB153-Elicited Hepatic Responses in the Immature, Ovariectomized C57BL/6 Mice: Comparative Toxicogenomic Effects of Dioxin and Non-Dioxin-Like Ligands”

    PubMed Central

    Kopec, Anna K.; Burgoon, Lyle D.; Ibrahim-Aibo, Daher; Mets, Bryan D.; Tashiro, Colleen; Potter, Dave; Sharratt, Bonnie; Harkema, Jack R.; Zacharewski, Timothy

    2010-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitous contaminants found as complex mixtures of coplanar and non-coplanar congeners. The hepatic temporal and dose-dependent effects of the most abundant non-dioxin-like congener, 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB153), were examined in immature, ovariectomized C57BL/6 mice, and compared to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the prototypical aryl hydrocarbon receptor (AhR) ligand. Animals were gavaged once with 300 mg/kg PCB153 or sesame oil vehicle and sacrificed 4, 12, 24, 72 or 168 h post dose. In the dose-response study, mice were gavaged with 1, 3, 10, 30, 100 or 300 mg/kg PCB153 or sesame oil for 24 h. Significant increases in relative liver weights were induced with 300 mg/kg PCB153 between 24 and 168 h, accompanied by slight vacuolization and hepatocellular hypertrophy. The hepatic differential expression of 186 and 177 genes was detected using Agilent 4 x 44 K microarrays in the time course (|fold change|≥1.5, P1(t)≥0.999) and dose-response (|fold change|≥1.5, P1(t)≥0.985) studies, respectively. Comparative analysis with TCDD suggests that the differential gene expression elicited by PCB153 was not mediated by the AhR. Furthermore, constitutive androstane and pregnane X receptor (CAR/PXR) regulated genes including Cyp2b10, Cyp3a11, Ces2, Insig2 and Abcc3 were dose-dependently induced by PCB153. Collectively, these results suggest that the hepatocellular effects elicited by PCB153 are qualitatively and quantitatively different from TCDD and suggestive of CAR/PXR regulation. PMID:20005886

  6. PCB153-elicited hepatic responses in the immature, ovariectomized C57BL/6 mice: Comparative toxicogenomic effects of dioxin and non-dioxin-like ligands

    SciTech Connect

    Kopec, Anna K.; Burgoon, Lyle D.; Ibrahim-Aibo, Daher; Mets, Bryan D.; Tashiro, Colleen; Potter, Dave; Sharratt, Bonnie; Harkema, Jack R.; Zacharewski, Timothy R.

    2010-03-15

    Polychlorinated biphenyls (PCBs) are ubiquitous contaminants found as complex mixtures of coplanar and non-coplanar congeners. The hepatic temporal and dose-dependent effects of the most abundant non-dioxin-like congener, 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153), were examined in immature, ovariectomized C57BL/6 mice, and compared to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the prototypical aryl hydrocarbon receptor (AhR) ligand. Animals were gavaged once with 300 mg/kg PCB153 or sesame oil vehicle and sacrificed 4, 12, 24, 72 or 168 h post dose. In the dose-response study, mice were gavaged with 1, 3, 10, 30, 100 or 300 mg/kg PCB153 or sesame oil for 24 h. Significant increases in relative liver weights were induced with 300 mg/kg PCB153 between 24 and 168 h, accompanied by slight vacuolization and hepatocellular hypertrophy. The hepatic differential expression of 186 and 177 genes was detected using Agilent 4 x 44 K microarrays in the time course (|fold change| >= 1.5, P1(t) >= 0.999) and dose-response (|fold change| >= 1.5, P1(t) >= 0.985) studies, respectively. Comparative analysis with TCDD suggests that the differential gene expression elicited by PCB153 was not mediated by the AhR. Furthermore, constitutive androstane and pregnane X receptor (CAR/PXR) regulated genes including Cyp2b10, Cyp3a11, Ces2, Insig2 and Abcc3 were dose-dependently induced by PCB153. Collectively, these results suggest that the hepatocellular effects elicited by PCB153 are qualitatively and quantitatively different from TCDD and suggestive of CAR/PXR regulation.

  7. Genetic variation in the CYP1A1 gene is related to circulating PCB118 levels in a population-based sample

    SciTech Connect

    Lind, Lars; Penell, Johanna; Syvänen, Anne-Christine; Axelsson, Tomas; Ingelsson, Erik; Morris, Andrew P.; Lindgren, Cecilia; Salihovic, Samira; Bavel, Bert van; Lind, P. Monica

    2014-08-15

    Several of the polychlorinated biphenyls (PCBs), i.e. the dioxin-like PCBs, are known to induce the P450 enzymes CYP1A1, CYP1A2 and CYP1B1 by activating the aryl hydrocarbon receptor (Ah)-receptor. We evaluated if circulating levels of PCBs in a population sample were related to genetic variation in the genes encoding these CYPs. In the population-based Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study (1016 subjects all aged 70), 21 SNPs in the CYP1A1, CYP1A2 and CYP1B1 genes were genotyped. Sixteen PCB congeners were analysed by high-resolution chromatography coupled to high-resolution mass spectrometry (HRGC/ HRMS). Of the investigated relationships between SNPs in the CYP1A1, CYP1A2 and CYP1B1 and six PCBs (congeners 118, 126, 156, 169, 170 and 206) that captures >80% of the variation of all PCBs measured, only the relationship between CYP1A1 rs2470893 was significantly related to PCB118 levels following strict adjustment for multiple testing (p=0.00011). However, there were several additional SNPs in the CYP1A2 and CYP1B1 that showed nominally significant associations with PCB118 levels (p-values in the 0.003–0.05 range). Further, several SNPs in the CYP1B1 gene were related to both PCB156 and PCB206 with p-values in the 0.005–0.05 range. Very few associations with p<0.05 were seen for PCB126, PCB169 or PCB170. Genetic variation in the CYP1A1 was related to circulating PCB118 levels in the general elderly population. Genetic variation in CYP1A2 and CYP1B1 might also be associated with other PCBs. - Highlights: • We studied the relationship between PCBs and the genetic variation in the CYP genes. • Cross sectional data from a cohort of elderly were analysed. • The PCB levels were evaluated versus 21 SNPs in three CYP genes. • PCB 118 was related to variation in the CYP1A1 gene.

  8. PCB Food Web Dynamics Quantify Nutrient and Energy Flow in Aquatic Ecosystems.

    PubMed

    McLeod, Anne M; Paterson, Gordon; Drouillard, Ken G; Haffner, G Douglas

    2015-11-01

    Measuring in situ nutrient and energy flows in spatially and temporally complex aquatic ecosystems represents a major ecological challenge. Food web structure, energy and nutrient budgets are difficult to measure, and it is becoming more important to quantify both energy and nutrient flow to determine how food web processes and structure are being modified by multiple stressors. We propose that polychlorinated biphenyl (PCB) congeners represent an ideal tracer to quantify in situ energy and nutrient flow between trophic levels. Here, we demonstrate how an understanding of PCB congener bioaccumulation dynamics provides multiple direct measurements of energy and nutrient flow in aquatic food webs. To demonstrate this novel approach, we quantified nitrogen (N), phosphorus (P) and caloric turnover rates for Lake Huron lake trout, and reveal how these processes are regulated by both growth rate and fish life history. Although minimal nutrient recycling was observed in young growing fish, slow growing, older lake trout (>5 yr) recycled an average of 482 Tonnes·yr(-1) of N, 45 Tonnes·yr(-1) of P and assimilated 22 TJ yr(-1) of energy. Compared to total P loading rates of 590 Tonnes·yr(-1), the recycling of primarily bioavailable nutrients by fish plays an important role regulating the nutrient states of oligotrophic lakes. PMID:26437236

  9. Reductive dechlorination of PCB-contaminated Raisin River sediments by anaerobic microbial granules

    SciTech Connect

    Natarajan, M.R.; Nye, J.; Wu, W.M.; Wang, H.; Jain, M.K.

    1997-07-05

    A polychlorinated biphenyl (PCB)-dechlorinating anaerobic microbial consortium, developed in a granular form, demonstrated extensive dechlorination of PCBs present in Raisin River sediments at room (20 to 22 C) and at a relatively low (12 C) temperature. Highly chlorinated PCB congeners were dechlorinated and less chlorinated compounds were produced. The homolog comparison showed that tri-, tetra-, penta-, hexa-, and heptachlorobiphenyl compounds decreased significantly, and mono- and dichlorobiphenyl compounds increased. After 32 weeks of incubation at 12 C, the predominant less chlorinated products included 2-, 4-, 2-2/26-, 24-, 2-4-, 24-2-, 26-2-, and 26-4-CB. Among these, 24- and 24-2-CB did not accumulate at room temperature, suggesting a further dechlorination of these congeners. Predominantly meta dechlorination (i.e., pattern M) was catalyzed by the microbial consortium in the granules. Dechlorination in the control studies without granules was not extensive. This study is the first demonstration of enhanced reductive dechlorination of sediment PCBs by an exogenous anaerobic microbial consortium.

  10. PCB and PBDE levels in a highly threatened dolphin species from the Southeastern Brazilian coast.

    PubMed

    Lavandier, Ricardo; Arêas, Jennifer; Quinete, Natalia; de Moura, Jailson F; Taniguchi, Satie; Montone, Rosalinda; Siciliano, Salvatore; Moreira, Isabel

    2016-01-01

    In the Northern coast of Rio de Janeiro State is located the major urban centers of the oil and gas industry of Brazil. The intense urbanization in recent decades caused an increase in human use of the coastal areas, which is constantly impacted by agricultural, industrial and wastewater discharges. Franciscana dolphin (Pontoporia blainvillei) is a small cetacean that inhabits coastal regions down to a 30 m depth. This species is considered the most threatened cetacean in the Western South Atlantic Ocean. This study investigated the levels of 52 PCB congeners and 9 PBDE congeners in liver of nine individuals found stranded or accidentally caught between 2011 and 2012 in the Northern coast of Rio de Janeiro. PCB mean levels ranged from 208 to 5543 ng g(-1) lw and PBDEs mean concentrations varied between 13.84 and 36.94 ng g(-1) lw. Contamination patterns suggest the previous use of Aroclor 1254, 1260 and penta-BDE mixtures in Brazil. While still few studies have assessed the organic contamination in cetaceans from the Southern Hemisphere, including Brazil, the levels found in this study could represent a health risk to these endangered species. PMID:26552541

  11. Developmental toxicity of PCB 126 (3,3',4,4',5-pentachlorobiphenyl) in nestling American kestrels (Falco sparverius)

    USGS Publications Warehouse

    Hoffman, D.J.; Melancon, M.J.; Klein, P.N.; Rice, C.P.; Eisemann, J.D.; Hines, R.K.; Spann, J.W.; Pendleton, G.W.

    1996-01-01

    Planar PCB congeners are embryotoxic and teratogenic to birds including American kestrels. The developmental toxicity of 3,3',4,4',5-pentachlorobiphenyl (PCB 126) was studied in the post-hatching kestrel as a model for the eagle. Nestlings were orally dosed for 10 days with 5 ul/g body weight of corn oil (controls) or the planar PCB 126 at concentrations of 50, 250, or 1000 ng/g body weight. Dosing with 50 ng/g of PCB 126 resulted in a hepatic concentration of 156 ng/g w.w., liver enlargement and mild coagulative necrosis, and over ten-fold increases in hepatic microsomal ethoxyresorufin-O-dealkylase (EROD) and benzyloxyresorufin-O-dealkylase (BROD), and approximately a 5-fold increase in methoxyresorufin-O-dealkylase (MROD). At this dose, mild to moderate lymphoid depletion of the spleen was apparent, and decreased follicle size and content of the thyroid. At 250 ng/g, concentration of PCB 126 in the liver was 380 ng/g with increasing multifocal coagulative necrosis, decreased bone growth, decreased spleen weight with lymphocyte depletion of the spleen and bursa, and degenerative lesions of the thyroid. At 1000 ng/g, the liver concentration was 1098 ng/g, accompanied by decreased bursa weight, decreased hepatic thiol concentration and increased plasma enzyme activities (ALT, AST, and LDH-L) in addition to the previous effects. Highly significant positive correlations were noted between liver concentrations of PCB 126 and the ratio of oxidized to reduced glutathone. These findings indicate that nestling kestrels are more susceptible to PCB 126 toxicity than adults, but less sensitive than embryos, and that planar PCBs are of potential hazard to nestling birds.

  12. Serum PCB levels in a representative sample of the Spanish adult population: the BIOAMBIENT.ES project.

    PubMed

    Huetos, O; Bartolomé, M; Aragonés, N; Cervantes-Amat, M; Esteban, M; Ruiz-Moraga, M; Pérez-Gómez, B; Calvo, E; Vila, M; Castaño, A

    2014-09-15

    This manuscript presents the levels of six indicator polychlorinated biphenyl (PCB) congeners (IUPAC nos. 28, 52, 101, 138, 153 and 180) in the serum of 1880 individuals from a representative sample of the Spanish working population recruited between March 2009 and July 2010. Three out of the six PCBs studied (180, 153 and 138) were quantified in more than 99% of participants. PCB 180 was the highest contributor, followed by PCBs 153 and 138, with relative abundances of 42.6%, 33.2% and 24.2%, respectively. In contrast, PCBs 28 and 52 were detected in only 1% of samples, whereas PCB 101 was detectable in 6% of samples. The geometric mean (GM) for ΣPCBs138/153/180 was 135.4 ng/g lipid (95% CI: 121.3-151.2 ng/g lipid) and the 95th percentile was 482.2 ng/g lipid. Men had higher PCB blood concentrations than women (GMs 138.9 and 129.9 ng/g lipid respectively). As expected, serum PCB levels increased with age and frequency of fish consumption, particularly in those participants younger than 30 years of age. The highest levels we found were for participants from the Basque Country, whereas the lowest concentrations were found for those from the Canary Islands. The Spanish population studied herein had similar levels to those found previously in Greece and southern Italy, lower levels than those in France and central Europe, and higher PCB levels than those in the USA, Canada and New Zealand. This paper provides the first baseline information regarding PCB exposure in the Spanish adult population on a national scale. The results will allow us to establish reference levels, follow temporal trends and identify high-exposure groups, as well as monitor implementation of the Stockholm Convention in Spain. PMID:25000579

  13. Measurement and modeling of urban atmospheric PCB concentrations on a small (8 km) spatial scale

    NASA Astrophysics Data System (ADS)

    Totten, Lisa A.; Stenchikov, Georgiy; Gigliotti, Cari L.; Lahoti, Nilesh; Eisenreich, Steven J.

    Atmospheric transport and deposition of polychlorinated biphenyls (PCBs) is an important problem for ecosystems around the world. Data from several monitoring networks demonstrate that atmospheric PCB concentrations are dramatically elevated in urban areas compared to rural or background regions, such that these urban emissions of PCBs support the regional and global transport and deposition of PCBs to more remote areas. Identifying and controlling the sources of urban atmospheric PCBs is thus essential in minimizing the regional and global transport and deposition of these compounds. From December 1999 to November 2000, gas-phase PCB concentrations were measured at two monitoring locations, ˜8 km apart, within the New York City metropolitan area, at Jersey City and Bayonne, NJ. Concentrations, congener patterns, and temporal patterns of PCBs differ dramatically at the two sites, suggesting that a significant source of atmospheric PCBs exists within 8 km of the Bayonne site, resulting in spikes in gas-phase PCB concentration at Bayonne that are not observed at Jersey City. The Regional Atmospheric Model System (RAMS) coupled with the Hybrid Particle and Concentration Transport model (HYPACT) was used to estimate that the PCB source near Bayonne emits a flux of ΣPCBs on the order of 100 g d -1. Extrapolation of this source magnitude to the area of New York City suggests that this urban area emits at least 300 kg yr -1ΣPCBs to the regional atmosphere, similar in magnitude to the flow of ΣPCB out of the Upper Hudson River into the New York/New Jersey Harbor.

  14. ENVIROGARD™ PCB TEST KIT, MILLIPORE, INC. - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    The Envirogard™ polychlorinated biphenyl (PCB) immunoassay test kit rapidly analyzes for PCB concentrations in soils. Soils samples are extracted using methanol; extracts and calibration solutions are added to test tubes coated with antibodies that bind PCB molecules. The soil ex...

  15. An assessment of PCB and PBDE contamination in two tropical dolphin species from the Southeastern Brazilian coast.

    PubMed

    Lavandier, Ricardo; Arêas, Jennifer; Dias, Patrick S; Taniguchi, Satie; Montone, Rosalinda; de Moura, Jailson Fulgencio; Quinete, Natalia; Siciliano, Salvatore; Moreira, Isabel

    2015-12-30

    PCBs and PBDEs were determined in two dolphin species, Sotalia guianensis and Steno bredanensis, from an upwelling system off the Central-northern coast of Rio de Janeiro, Brazil. PCB levels varied from 0.040 to 0.75 μg g(-1) lw in muscles and from 0.022 to 1.32 μg g(-1)lw in liver samples from S. guianensis. In S. bredanensis, values varied from 0.085 to 11.3 μg g(-1) lw in muscles and from 0.024 to 18.6 μg g(-1) lw in livers. PCB-138, -153 and -180 were the major PCB congeners detected in both species, while BDE-47 was the predominant PBDE congener found in both species. Higher concentrations in S. bredanensis were possibly related to the different feeding habits for both delphinid species. These results contribute to extend the database on organic contamination in cetaceans from the southern hemisphere, understanding their distribution and environmental fate in Southeastern Brazil. PMID:26506024

  16. Management of PCB laboratory wastes

    SciTech Connect

    1995-11-01

    Regulations promulgated by the US Environmental Protection Agency (EPA) under the Toxic Substances Control Act (TSCA) govern the management of polychlorinated biphenyls (PCBs), including use, storage, and disposal. Under TSCA, PCBs can only be used if the use is authorized under the TSCA regulations in 40 CFR 761; otherwise, the use of PCBs is prohibited and the PCBs must be disposed as PCB waste. 40 CFR 761.30(j) authorizes the use of PCBs in ``small quantities for research and development.`` Research and development activities are defined to include activities associated with laboratory analysis.

  17. DYNAMIC MASS BALANCE OF PCB (POLYCHLORINATED BIPHENYLS)

    EPA Science Inventory

    In Saginaw Bay, Lake Huron, about 3.7 metric tons of PCB remain in the active sediment and inputs from the Saginaw River and atmospheric deposition contribute about 1.4 kg PCB per day. In 1977 the U.S. E.P.A. initiated a research effort on Saginaw Bay which was chosen because of ...

  18. PCB intake from sport fishing along the Northern Illinois shore of Lake Michigan

    SciTech Connect

    Pellettieri, M.B.; Hallenbeck, W.H.; Brenniman, G.R.; Cailas, M.; Clark, M.

    1996-12-31

    Polychlorinated biphenyls (PCBs) are chlorinated hydrocarbons with an empirical formula of C{sub 12}H{sub 10-x}Cl{sub x}. The biphenyl can have from one to 10 chlorine substitutions resulting in 209 theoretical congeners. Commercial formulations of PCBs are complex mixtures of congeners; 125 congeners have been identified in commercial formulations. PCBs have entered the aquatic environment by industrial discharge, airborne deposition, and release from sediments. The most likely route of non-occupational human exposure to PCBs is from consumption of contaminated fish. PCBs are considered to be the most important contaminants in fish from the Great Lakes. Hence, in 1993 the Great Lakes Fish and Advisory Task Force developed a fish consumption advisory for the Great Lakes which incorporated a Health Protection Value (HPV) of 3.5 {mu}g of PCBs/day. This study combines the creel species, weight, and length distribution data with PCB monitoring data to quantitate the theoretical intake of PCBs by sport fishermen in the Chicago area. 6 refs., 3 tabs.

  19. Polychlorinated biphenyl (PCB) anaerobic degradation in marine sediments: microcosm study and role of autochthonous microbial communities.

    PubMed

    Matturro, Bruna; Ubaldi, Carla; Grenni, Paola; Caracciolo, Anna Barra; Rossetti, Simona

    2016-07-01

    Polychlorobiphenyl (PCB) biodegradation was followed for 1 year in microcosms containing marine sediments collected from Mar Piccolo (Taranto, Italy) chronically contaminated by this class of hazardous compounds. The microcosms were performed under strictly anaerobic conditions with or without the addition of Dehalococcoides mccartyi, the main microorganism known to degrade PCBs through the anaerobic reductive dechlorination process. Thirty PCB congeners were monitored during the experiments revealing that the biodegradation occurred in all microcosms with a decrease in hepta-, hexa-, and penta-chlorobiphenyls (CBs) and a parallel increase in low chlorinated PCBs (tri-CBs and tetra-CBs). The concentrations of the most representative congeners detected in the original sediment, such as 245-245-CB and 2345-245-CB, and of the mixture 2356-34-CB+234-245-CB, decreased by 32.5, 23.8, and 46.7 %, respectively, after only 70 days of anaerobic incubation without any bioaugmentation treatment. Additionally, the structure and population dynamics of the microbial key players involved in the biodegradative process and of the entire mixed microbial community were accurately defined by Catalyzed Reporter Deposition Fluorescence In Situ Hybridization (CARD-FISH) in both the original sediment and during the operation of the microcosm. The reductive dehalogenase genes of D. mccartyi, specifically involved in PCB dechlorination, were also quantified using real-time PCR (qPCR). Our results demonstrated that the autochthonous microbial community living in the marine sediment, including D. mccartyi (6.32E+06 16S rRNA gene copy numbers g(-1) sediment), was able to efficiently sustain the biodegradation of PCBs when controlled anaerobic conditions were imposed. PMID:26162439

  20. PCB dechlorination in anaerobic soil slurry reactors

    SciTech Connect

    Klasson, K.T.; Evans, B.S.

    1993-11-29

    Many industrial locations, including the US Department of Energy`s, have identified needs for treatment of polychlorinated biphenyl (PCB) wastes and remediation of PCB-contaminated sites. Biodegradation of PCBs is a potentially effective technology for the treatment of PCB-contaminated soils and sludges, including mixed wastes; however, a practical remediation technology has not yet been demonstrated. In laboratory experiments, soil slurry bioreactors inoculated with microorganisms extracted from PCB-contaminated sediments from the Hudson River have been used to obtain anaerobic dechlorination of PCBS. The onset of dechlorination activity can be accelerated by addition of nutritional amendments and inducers. After 15 weeks of incubation with PCB-contaminated soil and nutrient solution, dechlorination has been observed under several working conditions. The best results show that the average chlorine content steadily dropped from 4.3 to 3.5 chlorines per biphenyl over a 15-week period.

  1. Effects of Great Lakes fish consumption on brain PCB pattern, concentration, and progressive-ratio performance

    SciTech Connect

    Stewart, P.; Pagano, J.; Sargent, D.; Darvill, T.; Lonky, E.; Reihman, J.

    2000-01-01

    This study investigated the effects of consumption of Great Lakes fish on progressive ratio performance, and on the pattern and concentrations of brain polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethene (DDE), and mirex in the rat. Adult, male Sprague-Dawley rats were fed a 30% diet of either Lake Ontario salmon (LAKE), Pacific Ocean salmon, or lab chow control for 20 or 65 days. Following the treatment regimen, half the rats from each group were sacrificed immediately for gas chromatographic analysis of organochlorine contaminants, and the other half were tested on a multiple fixed-ratio-progressive-ratio reinforcement schedule and then sacrificed for analysis. Consumption of Lake Ontario fish resulted in significantly higher levels of brain PCBs, DDE, and mirex relative to controls, but still well within human exposure ranges. Consumption of Lake Ontario fish for 20 or 65 days produced an average brain PCB concentration of 457 and 934 ng/g fat, respectively. Consumption of laboratory rat chow or Pacific Ocean salmon for 20 or 65 days produced an average brain PCB concentration of 240, 464, and 441 ng/g fat, respectively. Moreover, both LAKE-fed groups showed a much more heavily chlorinated pattern of brain PCBs than all control groups, as evidenced by both significant increases in the most heavily chlorinated PCB congeners and significant increases in the average chlorine biphenyl.

  2. Development of a probabilistic PCB-bioaccumulation model for six fish species in the Hudson River

    SciTech Connect

    Stackelberg, K. von; Menzie, C.

    1995-12-31

    In 1984 the US Environmental Protection Agency (USEPA) completed a Feasibility Study on the Hudson River that investigated remedial alternatives and issued a Record of Decision (ROD) later that year. In December 1989 USEPA decided to reassess the No Action decision for Hudson River sediments. This reassessment consists of three phases: Interim Characterization and Evaluation (Phase 1); Further Site Characterization and Analysis (Phase 2); and, Feasibility study (Phase 3). A Phase 1 report was completed in August, 1991. The team then completed a Final Work Plan for Phase 2 in September 1992. This work plan identified various PCB fate and transport modeling activities to support the Hudson River PCB Reassessment Remedial Investigation and Feasibility Study (RI/FS). This talk provides a description of the development of a Probabilistic bioaccumulation models to describe the uptake of PCBs on a congener-specific basis in six fish species. The authors have developed a framework for relating body burdens of PCBs in fish to exposure concentrations in Hudson River water and sediments. This framework is used to understand historical and current relationships as well as to predict fish body burdens for future conditions under specific remediation and no action scenarios. The framework incorporates a probabilistic approach to predict distributions in PCB body burdens for selected fish species. These models can predict single population statistics such as the average expected values of PCBs under specific scenarios as well as the distribution of expected concentrations.

  3. Partitioning and removal of dioxin-like congeners in flue gases treated with activated carbon adsorption.

    PubMed

    Chi, Kai Hsien; Chang, Shu Hao; Huang, Chia Hua; Huang, Hung Chi; Chang, Moo Been

    2006-08-01

    Activated carbon adsorption is commonly used to control dioxin-like congener (PCDD/Fs and PCBs) emissions. Partitioning of PCDD/Fs and PCBs between vapor and solid phases and their removal efficiencies achieved with existing air pollution control devices (APCDs) at a large-scale municipal waste incinerator (MWI) and an industrial waste incinerator (IWI) are evaluated via intensive stack sampling and analysis. Those two facilities investigated are equipped with activated carbon injection (ACI) with bag filter (BF) and fixed activated carbon bed (FACB) as major PCDD/F control devices, respectively. Average PCDD/F and PCB concentrations of stack gas with ACI+BF as APCDs are 0.031 and 0.006ng-TEQ/Nm(3), and that achieved with FACB are 1.74 and 0.19ng-TEQ/Nm(3) in MWI and IWI, respectively. The results show that FACB could reduce vapor-phase PCDD/Fs and PCBs concentrations in flue gas, while the ACI+BF can effectively adsorb the vapor-phase dioxin-like congener and collect the solid-phase PCDD/Fs and PCBs in the meantime. Additionally, the results of the pilot-scale adsorption system (PAS) experimentation indicate that each gram activated carbon adsorbs 105-115ng-PCDD/Fs and each surface area (m(2)) of activated carbon adsorbs 10-25ng-PCDD/Fs. Based on the results of PAS experimentation, this study confirms that the surface area of mesopore+macropore (20-200A) of the activated carbon is a critical factor affecting PCDD/F adsorption capacity. PMID:16488462

  4. PCB126 Inhibits Adipogenesis of Human Preadipocytes

    PubMed Central

    Gadupudi, Gopi; Gourronc, Francoise A.; Ludewig, Gabriele; Robertson, Larry W.; Klingelhutz, Aloysius J.

    2014-01-01

    Emerging evidence indicates that persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), are involved in the development of diabetes. Dysfunctional adipocytes play a significant role in initiating insulin resistance. Preadipocytes make up a large portion of adipose tissue and are necessary for the generation of functional mature adipocytes through adipogenesis. PCB126 is a dioxin-like PCB and a potent aryl hydrocarbon receptor (AhR) agonist. We hypothesized that PCB126 may be involved in the development of diabetes through disruption of adipogenesis. Using a newly developed human preadipocyte cell line called NPAD (Normal PreADipocytes), we found that exposure of preadipocytes to PCB126 resulted in significant reduction in their subsequent ability to fully differentiate into adipocytes, more so than when the cells were exposed to PCB126 during differentiation. Reduction in differentiation by PCB126 was associated with downregulation of transcript levels of a key adipocyte transcription factor, PPARγ, and late adipocyte differentiation genes. An AhR antagonist, CH223191, blocked this effect. These studies indicate that preadipocytes are particularly sensitive to the effects of PCB126 and suggest that AhR activation inhibits PPARγ transcription and subsequent adipogenesis. Our results validate the NPAD cell line as a useful model for studying the effects of POPs on adipogenesis. PMID:25304490

  5. Effects of point-source PCB contamination on breeding performance and post-fledging survival in the dipper Cinclus cinclus.

    PubMed

    Ormerod, S J; Tyler, S J; Jüttner, I

    2000-12-01

    Despite widespread information on the incidence and biochemical effects of polychlorinated biphenyls (PCBs) in birds, field studies of effects on population processes are still scarce. This is particularly so in passerines. We therefore assessed breeding performance and post-fledging survival in dippers, Cinclus cinclus, breeding along the Afon Mule, a Welsh river where previous work indicated locally elevated PCB concentrations. We hypothesised that marked toxicological effects, including endocrine disruption, would be detectable as altered clutch-size, hatching success, nest success, brood-size, post-fledging survival or recruitment to the breeding population. Congener-specific analysis of PCBs in failed and deserted dipper eggs during 1990-93 revealed that geometric mean concentrations were four to 20 times higher along the Mule than elsewhere in Wales, UK. PCB signatures also varied highly significantly from other locations, with congeners 138, 153 and 180 dominant at the contaminated site, but 118 or 170 more frequent in eggs elsewhere. Subsequent analysis of surface runoff confirmed a small breaker's yard as a point source. Neither laying dates, clutch-sizes, brood-sizes, nest failure nor hatching failure along the contaminated Mule (n=46 breeding attempts and 218 eggs) differed significantly from dippers along adjacent reference rivers (n=82 breeding attempts and 315 eggs) or Welsh rivers as a whole (n=332 breeding attempts and 1534 eggs). Subsequent recaptures of breeding dippers ringed initially as nestlings were nearly identical between the Mule (7.7% of 182 nestlings), the reference set (7.5% of 323 nestlings) and all other Welsh rivers (7.3% of 2821 nestlings). These data illustrate the value of congener-specific analysis of bird's eggs in indicating local PCB sources. The data show also that PCBs can occur in dipper eggs at total concentrations of 0.49 (geometric mean)-1.29 (upper quartile) microg g(-1) wet mass without effects on breeding performance

  6. DEMONSTRATION BULLETIN: CLOR-N-SOIL PCB TEST KIT L2000 PCB/CHLORIDE ANALYZER - DEXSIL CORP.

    EPA Science Inventory

    DEXSIL CORP(Environmental Test Kits)The Dexsil Corporation (Dexsil) produces two test kits that detect polychlorinated biphenyls (PCB) in soil: the Dexsil Clor-N-Soil PCB Screening Kit, and the Dexsil L2000 PCB/Chloride Analyzer. The Dexsil Clor-N-Soil PCB Screening Kit extr...

  7. PCB and DDE methyl sulfones in mammals from Canada and Sweden

    SciTech Connect

    Bergman, A.; Kuroki, Hiroaki . Environmental Chemistry); Norstrom, R.J. . Environment Canada); Haraguchi, Koichi ); Beland, P. )

    1994-01-01

    Levels of PCB methyl sulfones (MeSO[sub 2]-CBs) and DDE methyl sulfones (MeSO[sub 2]-DDEs) have been determined in tissues from polar bear (Ursus martimus), beluga whale (Delphinapterus leucas), and false killer whale (Pseudorca crassidens) from the Canadian environment, and grey seal (Halichoerus grypus), otter (Lutra lutra), and wild mink (Mustela vison) from the Swedish environment. Up to 30 MeSO[sub 2]-CB congeners and three MeSO[sub 2]-DdE isomers were shown to be present in the analyzed tissues. The concentration of total MeSO[sub 2]-CBs ranged from 0.1 to 21 [mu]g/g extracted lipids. 3-MeSO[sub 2]-2,5,2[prime],4[prime],5[prime]-penta-CB is the dominating MeSO[sub 2]-CB congener in all the analyzed samples, but the corresponding 4-MeSO[sub 2]-CB also is present in high concentrations. A smaller number of MeSO[sub 2]-CBs, always dominated by the meta-substituted MeSO[sub 2]-CBs, were present in livers of grey seal, otter, and mink than in adipose tissue or muscle. In all studied mammals the concentration of MeSO[sub 2]-CBs were higher in liver than in blubber or muscle. Seven PCB congeners were identified as precursors of the PCB methyl sulfones: 2,4,2[prime],5[prime]-tetra-CB (CB-49),2,5,3[prime],4[prime]-tetra-CB (CB-70), 2,4,5,2[prime],5[prime]-penta-CB (CB-101),2,3,4,5,2[prime],5[prime]-penta-CB (CB-87),2,3,6,2[prime],4[prime],5[prime]-hexa-CB (CB-149),2,3,4,2[prime],3[prime],6[prime]-hexa-CB (CB-132), and 2,3,4,2[prime],5[prime]-hexa-CB (CB-141). All species except beluga whale contained 3-MeSO[sub 2]-4,4[prime]-DDE, but at a much lower concentration in mink and otter than in the other mammals. Polar bear and grey seal liver also contained 2-MeSO[sub 2]-4,4[prime]-DDE. The concentration of 2- and 3-MeSo[sub 2]-DDE ranged from 0.01 to 1.3 [mu]g/g extracted lipids.

  8. Dioxins and congener-specific polychlorinated biphenyls in three avian species from the Wisconsin River, Wisconsin

    USGS Publications Warehouse

    Custer, T.W.; Custer, Christine M.; Hines, Randy K.

    2002-01-01

    Sediments from the Wisconsin River, WI, USA are contaminated with 2,3,7,8-tetrachloro-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs). Wet weight concentrations of TCDD and PCBs in eggs were at background levels and highest in the piscivorous hooded merganser (Lophodytes cucullatus; geometric MEAN=7 pg/g TCDD and 0.92 I?g/g PCBs) and lowest in the omnivorous wood duck (Aix sponsa) (<1 pg/g and 0.07 I?g/g); concentrations in eggs of the insectivorous tree swallow (Tachycineta bicolor) were intermediate (<1 pg/g and 0.33 I?g/g). Positive accumulation rates of TCDD (8a??19 pg/day) and PCBs (0.4a??0.7 I?g/day) in tree swallow nestlings suggest that the Wisconsin River is the source of these contaminants for tree swallow nestlings. The lower representation of trichlorobiphenyls and tetrachorobiphenyls in hooded merganser eggs compared to wood duck or tree swallow eggs suggests that the hooded merganser or its diet has a greater ability to metabolize lower-numbered PCB congeners than wood ducks or tree swallows.

  9. Dioxins and congener-specific polychlorinated biphenyls in three avian species from the Wisconsin River, Wisconsin.

    PubMed

    Custer, T W; Custer, C M; Hines, R K

    2002-01-01

    Sediments from the Wisconsin River. WI. USA are contaminated with 2,3,7,8-tetrachloro-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs). Wet weight concentrations of TCDD and PCBs in eggs were at background levels and highest in the piscivorous = 7 pg/g TCDD a hooded merganser (Lophodytes cucullatus; geometric m ean nd 0.92 microg/g PCBs) a nd lowest in the omnivorous wood duck (Aix sponsa) (< 1 pg/g and 0.07 microg/g); concentrations in eggs of the insectivorous tree swallow (Tachycineta bicolor) were intermediate (< 1 pg/g and 0.33 pg/g). Positive accumulation rates of TCDD (8-19 pg/day) and PCBs (0.4-0.7 microg/day) in tree swallow nestlings suggest that the Wisconsin River is the source of these contaminants for tree swallow nestlings. The lower representation of trichlorobiphenyls and tetrachorobiphenyls in hooded merganser eggs compared to wood duck or tree swallow eggs suggests that the hooded merganser or its diet has a greater ability to metabolize lower-numbered PCB congeners than wood ducks or tree swallows. PMID:12166666

  10. Congenital PCB poisoning: a reevaluation

    SciTech Connect

    Miller, R.W.

    1985-05-01

    A review of the literature reveals a need to clarify the pathologic physiology of congenital polychlorinated biphenyl (PCB) poisoning, which is characterized by intrauterine growth retardation, brown staining of the skin and mucous membranes as in Addison's disease, natal teeth, widely open fontanelles and sagittal suture and apparent overgrowth of the gingiva. The skull abnormalities may represent irregular calcification, with natal teeth appearing because the bone of the mandible is penetrated more easily than usual. Some fetuses were poisoned at the time the mothers ingested the oil; others were affected in the subsequent years from residual contamination in the mothers' bodies. The misadventure in Japan was repeated in Taiwan in 1979. The seven congenital cases in Taiwan reported thus far seem to differ from those in Japan. In Taiwan the noses were somewhat black, two of the infants did not have low birth weight and the osseous abnormalities of the skull and gingival hyperplasia were not observed. Systematic followup studies should be made in Taiwan of the children born within 2 years of maternal poisoning with PCBs. Special attention should be given to age at first dentition and skull-X-rays for spotty calcification, among other measures of physical, neurologic and intellectual development.

  11. Reactivity Of Substituted Chlorines And Ensuing Dechlorination Pathways Of Select PCB Congeners With Pd/Mg Bimetallics

    EPA Science Inventory

    Conflicting accounts occur on the reactivity of substituted chlorines and the ensuing dechlorination pathway of PCBs undergoing catalytic hydrodechlorination (HDCl). In order to understand these relationships, intermediates and dechlorination pathways of carefully selected 17 co...

  12. Integrated Forensics Approach To Fingerprint PCB Sources In Sediments Using Immunoassays And GC/MS Congener Analyses

    EPA Science Inventory

    Determining the original source of contamination to a heterogeneous matrix such as sediments is a requirement for both clean-up and compliance programs within the military. Understanding the source of contaminants to sediment in industrial settings is a prerequisite to implement...

  13. Electrocatalytic Dechlorination Of A PCB Congener At A Palladized Granular Graphite-Packed Electrode: Reaction Equilibrium And Mechanism

    EPA Science Inventory

    Our previous study on the electrocatalytic dechlorination of 2-chlorobiphenyl at a Pd-loaded granular graphite-packed electrode demonstrated that the process did not follow the first order kinetics. The rate constant varied with the applied potential at the beginning, but later b...

  14. PCB trial burn in a modular, movable incinerator

    SciTech Connect

    Acharya, P. ); Reiter, B.A. )

    1987-01-01

    The authors discuss a trial burn conducted from March 11-13, 1986, in El Dorado, Arkanasas, of an MWP-2000 Modular Incinerations system to destroy PCB liquids, PCB items and PCB-contaminated solids in conformance with TSCA requirements. MWP-2000 has 4 main process modules--Rotary kiln, capable of destroying liquid PCBs and PCB-contaminated dirt; secondary combustor, capable of destroying high-level PCB liquids; heat recovery system, generating steam to drive the system's prime mover; and pollution control system that removes acid gases and fine particulates from the gas stream. The trial burn consisted of 5 separate tests. The first 3 tests were replicate tests. In these tests PCB-contaminated soils, having a PCB content of 1.8%, and PCB-contaminated fuel, having a content of 60%, were burned simultaneously in the secondary combustor. In the fourth test, PCB liquids, having a PCB content of 61%, were burned in the secondary combustor while the kiln was not operated. In the fifth test, pre-shredded capacitors having a PCB content of 18% were fed to the kiln and PCB liquids having a PCB concentration of 64% were fed to the secondary combustor. Trial burn results clearly demonstrate that a DREs of 99.999999% were achieved. HCl removal efficiencies of 99.9% were achieved. Total particulate emissions of 0.01-0.02 gr/DSCF were achieved. PCB contamination in the kiln ash and effluent residuals of <2 ppm were achieved.

  15. Identification of Sulfated Metabolites of 4-Chlorobiphenyl (PCB3) in the Serum and Urine of Male Rats

    PubMed Central

    Dhakal, Kiran; He, Xianran; Lehmler, Hans-Joachim; Teesch, Lynn M.; Duffel, Michael W.; Robertson, Larry W.

    2012-01-01

    Polychlorinated biphenyls (PCBs) are legacy pollutants that exert toxicities through various mechanisms. In the recent years exposure to PCBs via inhalation has been recognized as a hazard. Those PCBs with lower numbers of chlorine atoms (LC-PCBs) are semi-volatile, and have been reported in the urban air, as well as in the indoor air of older buildings. LC-PCBs are bioactivated to phenols and further to quinone electrophiles with genotoxic/carcinogenic potential. We hypothesized that phenolic LC-PCBs are subject to conjugation and excretion in the urine. PCB3, often present in high concentrations in air, is a prototypical congener for the study of the metabolism and toxicity of LC-PCBs. Our objective was to identify metabolites of PCB3 in urine that could be potentially employed in the estimation of exposure to LC-PCBs. Male Sprague Dawley rats (150–175 g) were housed in metabolism cages and received a single intraperitoneal injection of 600 µmol/kg body weight of PCB3. Urine was collected every four hours; rats were euthanized at 36 h and serum was collected. LC-MS analysis of urine before and after incubation with β-glucuronidase and sulfatase showed that sulfate conjugates were in higher concentrations than glucuronide conjugates and free phenolic forms. At least two major metabolites, and two minor metabolites were identified in urine that could be attributed to mercapturic acid metabolites of PCB3. Quantitation by authentic standards confirmed that approximately 3% of the dose was excreted in the urine as sulfates over 36 hours; with peak excretion occurring at 10–20 h after exposure. The major metabolites were 4’PCB3 sulfate, 3’PCB3 sulfate, 2’PCB3 sulfate, and presumably a catechol sulfate. The serum concentration of 4’PCB3 sulfate was 6.18±2.16 µg/mL. This is the first report that sulfated metabolites of PCBs are formed in vivo. These findings suggest a prospective approach for exposure assessment of LC- PCBs by analysis of phase II

  16. Microbial dehalogenation of a hexachlorinated PCB at low redox potential. Final report

    SciTech Connect

    Nuefeld, R.D.; Pedersen, S.F.

    1991-08-01

    In three studies using a single PCB congener, 2,2',4,4',5,5'-hexachlorobiphenyl degradation was observed at soil concentrations between 1000 and 1500 mg HCB/KG soil, but not in a fourth study conducted at 100 mg HCB/KG soil. Degradation did not occur in controls poisoned by 0.1% mercuric chloride; however, it was enhanced by the addition of a nutrient solution at approximate ratios of 100TOC:2N:1P. The degradation was observed in both soil and sand matrices. A study of different reducing agents revealed mixed effects on the degradation process; addition of equal parts of 1-cystine hydrochloride and sodium dithionite appeared to enhance degradation, while the use of 2 parts of sodium dithionite alone had little effect. Inoculating the HCB contaminated soil with an inoculum of chlorobenzoate dechlorinating bacteria from the University of Michigan resulted in degradation of the HCB.

  17. Accumulation of polychlorinated biphenyls (PCBs) and evaluation of hematological and immunological effects of PCB exposure on turtles.

    PubMed

    Yu, Shuangying; Halbrook, Richard S; Sparling, Donald W

    2012-06-01

    Concentrations of total polychlorinated biphenyls (PCBs), Aroclor 1260, and 26 congeners were measured in liver, fat, and eggs of red-eared slider turtles (Trachemys scripta elegans) collected from ponds near or on the Paducah Gaseous Diffusion Plant (PGDP), Kentucky, USA. Concentrations of total PCBs (wet mass) ranged from 0.002 to 0.480 mg/kg, 0.028 to 0.839 mg/kg, and 0.001 to 0.011 mg/kg in liver, fat, and eggs, respectively. Concentrations of Arochlor 1260 did not exceed 0.430, 0.419, and 0.007 mg/kg in liver, fat, and eggs, respectively. Exposure to PCBs in red-eared sliders collected from the PGDP is characterized by low concentrations of moderately chlorinated mono-ortho and di-ortho congeners (PCB 153, 180, and 118). Although PCB concentrations measured in the current study were low, chronic exposure to PCBs may have altered hematology and immunity of the turtles examined. Total white blood cell count and number of heterophils were negatively correlated with concentrations of total PCBs and Arochlor 1260, respectively. However, disease and other contaminants in the study area may influence the results. Because little is known regarding the influence of PCBs on hematology and immune function in turtles, additional study is needed to better evaluate results observed in the current study. PMID:22430883

  18. Polychlorinated biphenyls PCB 52, PCB 180, and PCB 138 impair the glutamate-nitric oxide-cGMP pathway in cerebellar neurons in culture by different mechanisms.

    PubMed

    Llansola, Marta; Montoliu, Carmina; Boix, Jordi; Felipo, Vicente

    2010-04-19

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants that accumulate in the food chain and are present in human blood and milk. Children born to mothers exposed to PCBs show cognitive deficits, which are reproduced in rats perinatally exposed to PCBs. It has been proposed that PCB-induced cognitive impairment is due to impairment of the glutamate-nitric oxide (NO)-cGMP pathway. The aim of the present work was to assess whether chronic exposure to the nondioxin-like PCB52, PCB138, or PCB180 alters the function of this pathway in primary cultures of rat cerebellar neurons and to assess whether different PCBs have similar or different mechanisms of action. PCB180 and PCB138 impair the function of the glutamate-NO-cGMP pathway at nanomolar concentrations, and PCB52 impairs the function of the glutamate-NO-cGMP pathway at micromolar concentrations. The mechanisms by which different PCBs impair the function of the glutamate-NO-cGMP pathway are different. Each PCB affects the pathway at more than one step but with different potency and, for some steps, in opposite ways. Exposure to the PCBs alters the basal concentrations of intracellular calcium, NO, and cGMP. The three PCBs increase NO; however, PCB52 and PCB138 increase basal cGMP, while PCB180 decreases it. PCB52 and PCB138 decrease the activation of soluble guanylate cyclase by NO, and PCB180 increases it. Long-term exposure to PCB52, PCB180, or PCB138 reduces the activation of NO synthase and the whole glutamate-NO-cGMP pathway in response to activation of N-methyl-d-aspartate receptors. The EC(50) was 300 nM for PCB52 and 2 nM for PCB138 or PCB180. These results show that chronic exposure to nondioxin like PCBs impairs the function of the glutamate-NO-cGMP pathway in cerebellar neurons by different mechanisms and with different potencies. Impaired function of this pathway would contribute to the cognitive alterations induced by perinatal exposure to PCBs in humans. PMID:20297801

  19. Bayesian Monte Carlo updating of Hudson River PCB model using water column PCB measurements

    SciTech Connect

    Zhang, S.; Toll, J.; Cothern, K.

    1995-12-31

    The authors have developed prior probability distributions for model parameters and terms describing physico-chemical processes in sediment and water column models of PCB fate in a segment of the lower Hudson River, and performed importance analyses to identify the key uncertainties affecting the models` predictive power. In this work, the authors employ field measurements of the mean total water column PCB concentration from nearby river segments to refine the prior probability distributions for the important parameters and terms in the water column PCB model, using Bayesian Monte Carlo analysis. The principal objectives of the current work are (1) to implement Bayesian Monte Carlo analysis, to demonstrate the technique and evaluate its potential benefits, and (2) to improve the parameterization of the water column PCB model on the basis of site-specific PCB concentration data. The Bayesian updating procedure resulted in improved estimates of PCB mass loading and re-suspension velocity terms, but posteriors for three other key parameters -- settling velocity and particulate PCB fractions in the water column and surface sediments -- were unaffected by the information extracted from the new field data. In addition, the authors found that some of the high posterior probability parameter vectors, though mathematically plausible, were physically implausible, as a consequence of the unrealistic (but common) Monte Carlo assumption that the model`s parameters are independently distributed. The implications of this and other findings are discussed.

  20. Similarity analysis of PAH and PCB bioaccumulation patterns in sediment-exposed Chironomus tentans larvae

    SciTech Connect

    Wood, L.W.; O`Keefe, P.; Bush, B.

    1997-02-01

    Larvae of the aquatic insect Chironomus tentans were exposed at the third or fourth instar stage to sediments collected near the outfalls of two aluminum foundries and an aluminum fabrication plant. Biota and sediment bioaccumulation factors (BFs), based on wet tissue weights and dry sediment weights, ranged from 0.07 to 0.27 for polycyclic aromatic hydrocarbons (PAHs) and from 0.22 to 1.42 for polychlorinated biphenyls (PCBs). A higher rate of metabolism of PAHs compared with PCBs could explain the differences in BF values for the two groups of chemicals. It was found, using community similarity procedures from the field of ecology, that the congener patterns for PAHs and PCBs bioaccumulated by the larvae differed from the pattern of the same compounds in the sediments to which they were exposed. Affinity analysis indicated that the larvae favored the higher molecular weight PAH and PCB congeners. Preferential ingestion of sediments with defined particle size ranges, metabolism, and octanol/water partition coefficients (log K{sub ow}) are factors that may have influenced the bioaccumulation patterns. However, no single factor could adequately account for the differences between the larval and sediment patterns.

  1. PCB biodegradation: Laboratory studies transitioned into the field

    SciTech Connect

    Abramowicz, D.A.

    1993-12-31

    Two distinct bacterial systems are known to be involved in PCB biotransformations. Both aerobic PCB biodegradation (Oxidative attack) and anaerobic PCB dechlorination (reductive attack) have been demonstrated in the laboratory. These results have been successfully reproducted in recent experiments performed in aquatic sediments. In 1991, GE performed a large scale test of in situ aerobic PCB biodegradation in the Upper Hudson River. The experiments involved six sealed caissons (six feet in diameter) lowered into Aroclor 1242 contaminated sediments that had already undergone extensive anaerobic PCB dechlorination. Stimulation of indigenous PCB-degrading microorganisms resulted in >50% biodegradation over 10 weeks. A large scale stimulation of in situ anaerobic PCB dechlorination in Housatonic River sediments contaminated with untransformed Aroclor 1260 was initiated in 1992. The experiments similarly involve six sealed caissons (six feet in diameter) lowered into contaminated sediments to investigate new methods developed to accelerate PCB dechlorination in the field. Preliminary results from this ongoing field test will be discussed.

  2. Polychlorinated biphenyl (PCB) and dichlorodiphenyl dichloroethylene (DDE) concentrations in the breast milk of women in Quebec.

    PubMed Central

    Dewailly, E; Ayotte, P; Laliberté, C; Weber, J P; Gingras, S; Nantel, A J

    1996-01-01

    OBJECTIVES: This study documented the concentration of polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethylene (DDE) in the breast milk of women from Quebec, Canada, and assessed the impact of various sociodemographic and lifestyle factors on these levels. METHODS: From 1988 to 1990, milk samples were obtained from 536 Quebec women and analyzed for seven PCB congeners and p,p'-DDE. Information was obtained on subjects' physical, sociodemographic, and lifestyle characteristics. RESULTS: Mean concentrations were 0.52 mg/kg lipids (95% confidence interval [CI] = 0.50, 0.54) and 0.34 mg/kg lipids (95% CI = 0.32, 0.35) for PCBs (Aroclor 1260) and DDE, respectively. Age and history of breast-feeding showed statistically significant correlations with PCB and DDE concentrations. CONCLUSIONS: Concentrations of PCBs and DDE measured in this study are at the lower end of the concentration range recently reported for women living in industrialized countries. The modulating factors identified here should be considered when conducting studies on organochlorine exposure and disease. PMID:8806375

  3. Evaluation of PCB dechlorination pathways in anaerobic sediment microcosms using an anaerobic dechlorination model.

    PubMed

    Demirtepe, Hale; Kjellerup, Birthe; Sowers, Kevin R; Imamoglu, Ipek

    2015-10-15

    A detailed quantitative analysis of anaerobic dechlorination (AD) pathways of polychlorinated biphenyls (PCBs) in sediment microcosms was performed by applying an anaerobic dechlorination model (ADM). The purpose of ADM is to systematically analyze changes in a contaminant profile that result from microbial reductive dechlorination according to empirically determined dechlorination pathways. In contrast to prior studies that utilized modeling tools to predict dechlorination pathways, ADM also provides quantification of individual pathways. As only microbial reductive dechlorination of PCBs occurred in the modeled laboratory microcosms, extensive analysis of AD pathways was possible without the complicating effect of concurrent physico-chemical or other weathering mechanisms. The results from this study showed: (1) ninety three AD pathways are active; (2) tetra- to hepta-chlorobiphenyl (CB) congeners were common intermediates in several AD pathways, penta-CBs being the most frequently observed; (3) the highest rates of dechlorination were for penta-CB homologs during the initial 185 days; (4) the dominant terminal products of AD were PCB 32(26-4), 49(24-25), 51(24-26), 52(25-25), 72(25-35), 73(26-35) and 100(246-24), (5) potential toxicity of the sediment was reduced. ADM serves as a powerful tool not only for a thorough analysis of AD pathways, but also for providing necessary input for numerical fate models (as a degradation term) that investigate dechlorination products or outcome of natural attenuation, or bioremediation/bioaugmentation of PCB-impacted sediments. PMID:25913678

  4. Bare PCB test method based on AI

    NASA Astrophysics Data System (ADS)

    Li, Aihua; Zhou, Huiyang; Wan, Nianhong; Qu, Liangsheng

    1995-08-01

    The shortcomings of conventional methods used for developing test sets on current automated printed circuit board (PCB) test machines consist of overlooking the information from CAD, historical test data, and the experts' knowledge. Thus, the generated test sets and proposed test sequence may be sub-optimal and inefficient. This paper presents a weighting bare PCB test method based on analysis and utilization of the CAD information. AI technique is applied for faults statistics and faults identification. Also, the generation of test sets and the planning of test procedure are discussed. A faster and more efficient test system is achieved.

  5. Printed Circuit Board Design (PCB) with HDL Designer

    NASA Technical Reports Server (NTRS)

    Winkert, Thomas K.; LaFourcade, Teresa

    2004-01-01

    Contents include the following: PCB design with HDL designer, design process and schematic capture - symbols and diagrams: 1. Motivation: time savings, money savings, simplicity. 2. Approach: use single tool PCB for FPGA design, more FPGA designs than PCB designers. 3. Use HDL designer for schematic capture.

  6. 40 CFR 761.274 - Reporting PCB concentrations in samples.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Reporting PCB concentrations in... COMMERCE, AND USE PROHIBITIONS Cleanup Site Characterization Sampling for PCB Remediation Waste in Accordance with § 761.61(a)(2) § 761.274 Reporting PCB concentrations in samples. (a) Report all...

  7. 40 CFR 761.274 - Reporting PCB concentrations in samples.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Reporting PCB concentrations in... COMMERCE, AND USE PROHIBITIONS Cleanup Site Characterization Sampling for PCB Remediation Waste in Accordance with § 761.61(a)(2) § 761.274 Reporting PCB concentrations in samples. (a) Report all...

  8. 40 CFR 761.274 - Reporting PCB concentrations in samples.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Reporting PCB concentrations in... COMMERCE, AND USE PROHIBITIONS Cleanup Site Characterization Sampling for PCB Remediation Waste in Accordance with § 761.61(a)(2) § 761.274 Reporting PCB concentrations in samples. (a) Report all...

  9. 40 CFR 761.125 - Requirements for PCB spill cleanup.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Requirements for PCB spill cleanup..., AND USE PROHIBITIONS PCB Spill Cleanup Policy § 761.125 Requirements for PCB spill cleanup. (a... minimize reporting burdens on governments as well as the regulated community. (i) Where a spill...

  10. 40 CFR 761.125 - Requirements for PCB spill cleanup.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Requirements for PCB spill cleanup..., AND USE PROHIBITIONS PCB Spill Cleanup Policy § 761.125 Requirements for PCB spill cleanup. (a... minimize reporting burdens on governments as well as the regulated community. (i) Where a spill...

  11. 40 CFR 761.125 - Requirements for PCB spill cleanup.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Requirements for PCB spill cleanup..., AND USE PROHIBITIONS PCB Spill Cleanup Policy § 761.125 Requirements for PCB spill cleanup. (a... minimize reporting burdens on governments as well as the regulated community. (i) Where a spill...

  12. 40 CFR 761.125 - Requirements for PCB spill cleanup.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Requirements for PCB spill cleanup..., AND USE PROHIBITIONS PCB Spill Cleanup Policy § 761.125 Requirements for PCB spill cleanup. (a... minimize reporting burdens on governments as well as the regulated community. (i) Where a spill...

  13. 40 CFR 761.125 - Requirements for PCB spill cleanup.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Requirements for PCB spill cleanup..., AND USE PROHIBITIONS PCB Spill Cleanup Policy § 761.125 Requirements for PCB spill cleanup. (a... minimize reporting burdens on governments as well as the regulated community. (i) Where a spill...

  14. DEMONSTRATION BULLETIN: ENVIROGARD™ PCB TEST KIT - MILLIPORE, INC.

    EPA Science Inventory

    The EnviroGard™ polychlorinated biphenyl (PCB) immunoassay test kit rapidly analyzes for PCB concentrations in soils. Soil sample extracts are added to test tubes coated with antibodies that bind PCB molecules. The excess soil extracts are washed out of the tubes after incubat...

  15. Proof of concept for the use of macroinvertebrates as indicators of polychlorinated biphenyls (PCB) contamination in Lake Hartwell.

    PubMed

    Lazorchak, James M; Griffith, Michael B; Mills, Marc; Schubauer-Berigan, Joseph; McCormick, Frank; Brenner, Richard; Zeller, Craig

    2015-06-01

    The US Environmental Protection Agency (USEPA) develops methods and tools for evaluating risk management strategies for sediments contaminated with polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and other legacy pollutants. Monitored natural recovery is a risk management alternative that relies on existing physical, chemical, and biological processes to contain, destroy, and/or reduce the bioavailability or toxicity of in-place contaminants. These naturally occurring processes are monitored to ensure that management and recovery are progressing as expected. One approach frequently used to evaluate the recovery of contaminated sediments and associated biota is the assessment of contaminant tissue levels, or body burden concentrations, in top trophic level fish. In the present study, aquatic invertebrates were examined as an indicator of recent exposure to PCBs. The approach aimed to determine whether invertebrates collected using artificial substrates (i.e., Hester-Dendy samplers) could be used to discriminate among contaminated sites through the analyses of PCBs in whole homogenates of macroinvertebrates. Macroinvertebrates were sorted, preserved, and analyzed for total PCBs (t-PCBs), by summing 107 PCB congeners. Macroinvertebrate body burden concentrations showed similar trends to sediment t-PCB concentrations at the sites sampled. The results indicate that macroinvertebrates can be used to assess sediment contamination among sites that have different PCB contamination levels. PMID:25663426

  16. In utero exposure to environmentally relevant concentrations of PCB 153 and PCB 118 disrupts fetal testis development in sheep.

    PubMed

    Krogenæs, Anette K; Ropstad, Erik; Gutleb, Arno C; Hårdnes, Nina; Berg, Vidar; Dahl, Ellen; Fowler, Paul A

    2014-01-01

    Polychlorinated biphenyls (PCB) are environmental pollutants linked to adverse health effects including endocrine disruption and disturbance of reproductive development. This study aimed to determine whether exposure of pregnant sheep to three different mixtures of PCB 153 and PCB 118 affected fetal testis development. Ewes were treated by oral gavage from mating until euthanasia (d 134), producing three groups of fetuses with distinct adipose tissue PCB levels: high PCB 153/low PCB 118 (n = 13), high PCB 118/low PCB 153 (n = 14), and low PCB 153/low PCB 118 (n = 14). Fetal testes and blood samples were collected for investigation of testosterone, testis morphology, and testis proteome. The body weight of the offspring was lower in the high PCB compared to the low PCB group, but there were no significant differences in testis weight between groups when corrected for body weight. PCB exposure did not markedly affect circulating testosterone. There were no significant differences between groups in number of seminiferous tubules, Sertoli cell only tubules, and ratio between relative areas of seminiferous tubules and interstitium. Two-dimensional (2D) gel-based proteomics was used to screen for proteomic alterations in the high exposed groups relative to low PCB 153/low PCB 118 group. Twenty-six significantly altered spots were identified by liquid chromatography (LC)-mass spectroscopy (MS)/MS. Changes in protein regulation affected cellular processes as stress response, protein synthesis, and cytoskeleton regulation. The study demonstrates that in utero exposure to different environmental relevant PCB mixtures exerted subtle effects on developing fetal testis proteome but did not significantly disturb testis morphology and testosterone production. PMID:24754397

  17. REMEDIATION OF PCB IN CONTAMINATED SOIL

    EPA Science Inventory

    A pilot-scale study will be conducted to evaluate the bioremedial techniques of natural attenuation, sequenced anaerobic/aerobic treatment, and addition of a commercially available microbial amendment product for use in treating PCB contaminated soils at Air Force Base sites. Th...

  18. Potency of PCDD, PCDF, PCB mixture to produce salmonid developmental mortality compared to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

    SciTech Connect

    Walker, M.K.; Zabel, E.W.; Peterson, R.E.; Butterworth, B.C.; Cook, P.M.

    1994-12-31

    The combined presence of TCDD-like polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) in feral fish eggs can be expressed as TCDD equivalents (TEQs), assuming congeners interact additively. To test this assumption, early life stage (ELS) mortality was assessed following exposure of lake trout and rainbow trout eggs to control, 7 graded doses of TCDD, or 14 graded doses of a mixture containing 11 TCDD-like PCDDs, PCDFs, PCBs, and 3 nonTCDD-like PCBs, mimicking congener ratios in Lake Michigan lake trout eggs. Lake trout eggs were exposed to waterborne TCDD or mixture and egg congener concentrations determined by GC/MS. Rainbow trout eggs were injected with a known dose of TCDD or mixture. Egg TEQs were calculated as the sum of egg congener concentration multiplied by fish-specific toxic equivalency factors. For both species, dose response curves for ELS mortality versus egg TCDD dose and egg TEQ dose were parallel. However, the mixture dose-response curve was shifted to the right of that for TCDD by 1.5--1.8 fold. LD{sub 50}S for lake trout were 200 pg TCDD/g and 362 pg TEQ/g. Based on TEQs, developmental toxicity of the PCDD, PCDF, PCB mixture was less than additive.

  19. Toxic effect of PBDE-47 on thyroid development, learning, and memory, and the interaction between PBDE-47 and PCB153 that enhances toxicity in rats.

    PubMed

    He, Ping; Wang, Aiguo; Niu, Qiang; Guo, Lijuan; Xia, Tao; Chen, Xuemin

    2011-04-01

    Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) are widespread environmental contaminants. There are potential interactive effects between PBDEs and PCBs, as these compounds share similar structures. The developmental neurotoxicity of 2, 2', 4, 4'-tetrabromodiphenyl ether (PBDE-47) and the interaction of PBDE-47 with 2, 2', 4, 4', 5, 5'-hexachlorobipheny (PCB153) were investigated herein, as the dominant congener forms of PBDEs and PCBs, respectively. SD rats were exposed to a single oral dose of PBDE-47 (1, 5, and 10 μg/g) and/or PCB153 (5 μg/g) on post-natal day (PND) 10. Concentrations of PBDE-47, triiodothyronine (T(3)), thyroxine (T(4)), and thyroid-stimulating hormone (TSH) in serum; organ-to-body weight ratios; as well as long-term learning and memory were measured in 2-month-old rats. The present study found that some doses of PBDE-47 decreased the organ-to-body weight ratios of the thyroid and uterus, decreased the concentration of T(4) in serum, and increased the organ-to-body weight ratio of the ovaries (p < 0.05). PCB153 could increase the action of PBDE-47 during combined exposure, but this interaction was not found between PBDE-47 and PCB153. In a Morris water maze experiment, the latency periods were significantly prolonged and time ratios were obviously depressed in all PBDE-47-treated groups compared to the control (p < 0.05); furthermore, significant interactions between PBDE-47 and PCB153 were observed (p < 0.05). In conclusion, PBDE-47 may depress thyroid development as well as the long-term learning and memory capabilities in adult rats exposed to PBDE-47 on PND 10. PCB153 can interact with PBDE-47, resulting in an increase in developmental neurotoxicity. PMID:20947653

  20. Environmental and health hazards from recycling PCB sources

    SciTech Connect

    Greichus, Y.A.; Dohman, B.A.

    1980-06-01

    Soil, corn plants, foliage, earthworms, and small rodents from areas surrounding two electrical salvage companies involved in reconditioning old transformers had unusually high levels of PCB's. Levels decreased as distance from the factories increased. PCB's were dispersed into the air through incineration of waste oils; water and soil contamination was caused by runoff from the factories. PCB's found to be present in the contaminated areas and in the waste oil closely resembled Aroclor 1260. Soil samples taken from depths of 2-4 in showed degradation of some PCB isomers. PCB concentrations in corn cobs and kernels were 0.05 ppm, whereas leaves contained PCB levels of up to 2.2 ppm. PCB levels in earthworms and small rodents collected near the factories were considerably higher than levels in the same types of animals collected from other areas. (10 references, 2 tables)

  1. Chemical contamination of the Rybinsk Reservoir, northwest Russia: relationship between liver polychlorinated biphenyls (PCB) content and health indicators in bream (Abramis brama)

    USGS Publications Warehouse

    Chuiko, Grigorii M.; Tillitt, Donald E.; Zajicek, James L.; Flerov, Boris A.; Stepanova, Vera M.; Zhelnin, Yuri Y.; Podgornaya, Vera A.

    2007-01-01

    The Rybinsk Reservoir (Russia) is the largest artificial waterbody in Europe (4550 km2) and provides drinking water for population of the cities located along the coast line. Industrialization in Cherepovets at the northeastern portion of the reservoir, including one of the largest metallurgical facilities in Europe, has resulted in chemical contamination of the reservoir. The extent of polychlorinated biphenyls (PCB) contamination in bream liver, a common fish species, taken from six locations in the Rybinsk Reservoir and Volga River, and biochemical and morphometric biomarkers of fish health were investigated. Liver PCB concentrations ranged from non-detected to 3.4 μg/g wet wt of liver, with the greatest concentrations found in fish taken near the industrialized area in Sheksna Reach of Rybinsk Reservoir. The source of the bream contamination is the PCB pollution of bottom organisms and sediments conditioned with industrialization facilities of Cherepovets. The patterns of the PCB congeners in the livers of bream taken near Cherepovets were similar at all of the stations that were sampled around the reservoir and Volga River. Among the common fish health biomarkers used only liver total ChE activity and liver-somatic index in bream near Cherepovets can reflect environmental pollution. Other morphometric (FCF, Clark’s condition factors, and spleen-somatic index) and biochemical (protein content and acetylcholinesterase activity in the brain) biomarkers related with fish health varied among locations, but were not correlated to the concentrations of PCBs in the bream livers.

  2. Chemical contamination of the Rybinsk Reservoir, northwest Russia: Relationship between liver polychlorinated biphenyls (PCB) content and health indicators in bream (Abramis brama)

    USGS Publications Warehouse

    Chuiko, G.M.; Tillitt, D.E.; Zajicek, J.L.; Flerov, B.A.; Stepanova, V.M.; Zhelnin, Y.Y.; Podgornaya, V.A.

    2007-01-01

    The Rybinsk Reservoir (Russia) is the largest artificial waterbody in Europe (4550 km2) and provides drinking water for population of the cities located along the coast line. Industrialization in Cherepovets at the northeastern portion of the reservoir, including one of the largest metallurgical facilities in Europe, has resulted in chemical contamination of the reservoir. The extent of polychlorinated biphenyls (PCB) contamination in bream liver, a common fish species, taken from six locations in the Rybinsk Reservoir and Volga River, and biochemical and morphometric biomarkers of fish health were investigated. Liver PCB concentrations ranged from non-detected to 3.4 ??g/g wet wt of liver, with the greatest concentrations found in fish taken near the industrialized area in Sheksna Reach of Rybinsk Reservoir. The source of the bream contamination is the PCB pollution of bottom organisms and sediments conditioned with industrialization facilities of Cherepovets. The patterns of the PCB congeners in the livers of bream taken near Cherepovets were similar at all of the stations that were sampled around the reservoir and Volga River. Among the common fish health biomarkers used only liver total ChE activity and liver-somatic index in bream near Cherepovets can reflect environmental pollution. Other morphometric (FCF, Clark's condition factors, and spleen-somatic index) and biochemical (protein content and acetylcholinesterase activity in the brain) biomarkers related with fish health varied among locations, but were not correlated to the concentrations of PCBs in the bream livers. ?? 2006 Elsevier Ltd. All rights reserved.

  3. Synthesis of Am80 (tamibarotene) prodrug candidates, congeners and metabolites.

    PubMed

    Muratake, Hideaki; Amano, Yohei; Toda, Takahiro; Sugiyama, Kiyoshi; Shudo, Koichi

    2013-01-01

    Compound 1 (IT-M-07000) was previously reported as a candidate prodrug of Am80 (Tamibarotene; used to treat acute promyelocytic leukemia), and shown to be efficiently metabolized to Am80 via β-oxidation. Here, we describe in detail the synthesis of 1, together with another tetradeuterated candidate prodrug, IT-YA-00616 (2), as well as two congeners, and several metabolic intermediates of 1 previously detected in mouse plasma. PMID:23902867

  4. PCB concentrations of lake whitefish (Coregonus clupeaformis) vary by sex

    USGS Publications Warehouse

    Madenjian, Charles P.; Ebener, Mark P.; Sepulveda, Maria S.

    2015-01-01

    We determined whole-fish polychlorinated biphenyl (PCB) concentrations in 26 female lake whitefish (Coregonus clupeaformis) and 34 male lake whitefish from northern Lake Huron. In 5 of the 26 female lake whitefish, we also determined PCB concentrations in the somatic tissue and ovaries. In addition, bioenergetics modeling was used to determine the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 60 ng/g and 80 ng/g, respectively; thus males were 34% higher in PCB concentration compared with females. Based on the PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 2.5%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain, to any degree, the higher PCB concentrations observed in males compared with females. Bioenergetics modeling results indicated that the growth dilution effect could account for males being only 0.7% higher in PCB concentration compared with females. Thus, the growth dilution effect contributed very little to the observed difference in PCB concentrations between the sexes. We conclude that males were higher than females in PCB concentration most likely due to a higher rate of energy expenditure, stemming from greater activity and a greater resting metabolic rate. A higher rate of energy expenditure leads to a higher rate of food consumption, which, in turn, leads to a higher PCB accumulation rate.

  5. PCB levels in human fluids: Sheboygan cohort study, Sheboygan maternal/infant PCB study

    SciTech Connect

    Smith, B.J.

    1983-01-01

    The PCB problem in the United States today has been raised to national concern with the discovery of PCBs in human breast milk above the highest recommended level for any commercially sold flood. This study, done in Sheboygan, Wisconsin in 1980-81, was to determine if (1) there were high levels of PCBs in mother's serum and breast milk in the vicinity of a PCB spill, (2) if these levels could be linked to the women's consumption of local fish, and (3) if the infants born to these women in the study showed signals of impaired health, growth, and development. Seventy-three women participated in the study, 62 who were breast-feeding their children, and 11 who were bottle-feeding their children. The serum PCB levels for the study population ranged from 1.29 to 14.90 ppb with a mean of 5.76 ppb. The breast milk PCB levels for the women who were breast feeding was 0.29 to 4.04 ppm with a mean of 1.13 ppm. The infants showed signs of impaired health as a result of in utero exposure to PCBs. No negative effects from exposure to breast milk PCB could be discerned up to 4 months postpartum.

  6. Bioaccumulation of toxaphene congeners in the lake superior food web

    USGS Publications Warehouse

    Muir, D.C.G.; Whittle, D.M.; De Vault, D. S.; Bronte, C.R.; Karlsson, H.; Backus, S.; Teixeira, C.

    2004-01-01

    The bioaccumulation and biotransformation of toxaphene was examined in the food webs of Lake Superior and Siskiwit Lake (Isle Royale) using congener specific analysis as well as stable isotope ratios of carbon and nitrogen to characterize food webs. Toxaphene concentrations (calculated using technical toxaphene) in lake trout (Salvelinus namaycush) from the western basin of Lake Superior (N = 95) averaged (±SD) 889 ± 896 ng/g wet wt and 60 ± 34 ng/g wet wt in Siskiwit Lake. Major congeners in lake trout were B8-789 (P38), B8-2226 (P44), B9-1679 (P50), and B9-1025 (P62). Toxaphene concentrations were found to vary seasonally, especially in lower food web organisms in Lake Superior and to a lesser extent in Siskiwit Lake. Toxaphene concentrations declined significantly in lake herring (Coregonus artedii), rainbow smelt (Omerus mordax), and slimy sculpin (Cottus cognatus) as well as in zooplankton (> 102 &mn;m) and Mysis (Mysis relicta) between May and October. The seasonal variation may reflect seasonal shifts in the species abundance within the zooplankton community. Trophic magnification factors (TMF) derived from regressions of toxaphene congener concentrations versus δ15N were > 1 for most octa- and nonachlorobornanes in Lake Superior except B8-1413 (P26) and B9-715. Log bioaccumulation factors (BAFs) for toxaphene congeners in lake trout (ng/g lipid/ng/L dissolved) ranged from 4.54 to 9.7 and were significantly correlated with log octanol-water partition coefficients. TMFs observed for total toxaphene and congener B9-1679 in Lake Superior were similar to those in Arctic lakes, as well as to previous studies in the Great Lakes, which suggests that the bioaccumulation behavior of toxaphene is similar in pelagic food webs of large, cold water systems. However, toxaphene concentrations were lower in lake trout from Siskiwit Lake and lakes in northwestern Ontario than in Lake Superior possibly because of shorter food chains and greater reliance on zooplankton or

  7. PCB's in Suburban Watershed, Reston, Va

    USGS Publications Warehouse

    Martell, J.M.; Rickert, D.A.; Siegel, F.R.

    1975-01-01

    Polychlorinated biphenyl concentrations in Lake Anne basin increased from water (<0.05-0.2 ppb), to bed sediment (<2.5-105 ppb), to fish (140-700 ppb) in an average ratio of 1:500:3000. The highest concentrations were observed in the lake, which is 10 years old, and receives no sewage or industrial waste discharges. Evidence indicates that the polvchlorinated biphenyls (PCB's) originate from diffuse sources associated with urban development and living.

  8. Decontamination and disposal of PCB wastes.

    PubMed Central

    Johnston, L E

    1985-01-01

    Decontamination and disposal processes for PCB wastes are reviewed. Processes are classed as incineration, chemical reaction or decontamination. Incineration technologies are not limited to the rigorous high temperature but include those where innovations in use of oxident, heat transfer and residue recycle are made. Chemical processes include the sodium processes, radiant energy processes and low temperature oxidations. Typical processing rates and associated costs are provided where possible. PMID:3928363

  9. PCB-Based Break-Out Box

    NASA Technical Reports Server (NTRS)

    Lee, Jason H.

    2011-01-01

    Break-out boxes (BOBs) are necessary for all electrical integration/cable checkouts and troubleshooting. Because the price of a BOB is high, and no work can be done without one, often the procedure stops, simply waiting for a BOB. A less expensive BOB would take less time in the integration, testing, and troubleshooting process. The PCB-based BOB works and looks the same as a standard JPL BOB, called Gold Boxes. The only differences between the old BOB and the new PCB-based BOB is that the new one has 80 percent of its circuitry in a printed circuit board. This process reduces the time for fabrication, thus making the BOBs less expensive. Moreover, because of its unique design, the new BOBs can be easily assembled and fixed. About 80 percent of the new PCB-based BOB is in a $22 (at the time of this reporting) custom-designed, yet commercially available PCB. This device has been used successfully to verify that BOB cables were properly made. Also, upon completion, the BOB was beeped out via a multimeter to ensure that all sockets on the connectors were properly connected to the respective banana jack. When compared to the Gold Box BOBs, the new BOB has many advantages. It is much more cost efficient, it delivers equal usability at substantially lower cost of the BOB, and the Gold Box is much heavier when compared to the new BOB. The new BOB is also a bit longer and much more versatile in that connectors are easily changeable and if a banana jack is broken, it can be replaced instead of throwing away an entire BOB.

  10. PCB with fully integrated optical interconnects

    NASA Astrophysics Data System (ADS)

    Langer, Gregor; Satzinger, Valentin; Schmidt, Volker; Schmid, Gerhard; Leeb, Walter R.

    2011-01-01

    The increasing demand for miniaturization and design flexibility of polymer optical waveguides integrated into electrical printed circuit boards (PCB) calls for new coupling and integration concepts. We report on a method that allows the coupling of optical waveguides to electro-optical components as well as the integration of an entire optical link into the PCB. The electro-optical devices such as lasers and photodiodes are assembled on the PCB and then embedded in an optically transparent material. A focused femtosecond laser beam stimulates a polymerization reaction based on a two-photon absorption effect in the optical material and locally increases the refractive index of the material. In this way waveguide cores can be realized and the embedded components can be connected optically. This approach does not only allow a precise alignment of the waveguide end faces to the components but also offers a truly 3-dimensional routing capability of the waveguides. Using this technology we were able to realize butt-coupling and mirror-coupling interface solutions in several demonstrators. We were also manufacturing demonstrator boards with fully integrated driver and preamplifier chips, which show very low power consumption of down to 10 mW for about 2.5 Gbit/s. Furthermore, demonstrators with interconnects at two different optical layers were realized.

  11. PCB augments LH-induced progesterone synthesis

    SciTech Connect

    Fuller, G.B.; Knauf, V.; Mueller, W.; Hobson, W.C.

    1980-07-01

    A great deal of attention has been focused on various environmental contaminants and their toxic effects on mammalian systems. Important among the compounds studied are the organochlorine pesticides and the polychlorinated biphenyls (PCB). The accumulation and persistence of these contaminants in the biosphere has accentuated their public health significance and limited their widespread commercial utilization. Changes in reproductive function have proven to be one of the more detrimental effects of chronic exposure to PCB or hexachlorobenzene (HCB). Reports in the literature have implicated potential target tissues such as the ovary, steroid-hydroxylating enzymes in the liver, and hypothalamus. The present experiment was designed to study the effect of acute in-vivo exposure to PCB (Clophen A-30) and HCB on LH-induced progesterone synthesis in-vitro. In order to obtain large amounts of luterin tissue relatively uniform in nature, the PMS-HCG primed immature rat model was utilized. This priming procedure, as described by Parlow (1958), results in a pronounced capacity for progesterone synthesis by the excessive numbers of induced corpora.

  12. Evaluating alleged drinking after driving--the hip-flask defence. Part 2. Congener analysis.

    PubMed

    Iffland, R; Jones, A W

    2003-01-01

    The second part of this review describes the principles and practice of forensic congener analysis as an alternative way to evaluate claims of drinking alcohol after driving. Congener analysis was developed, perfected and practised in Germany as a way to evaluate hip-flask defences. This kind of defence challenge arises frequently when the drunk driving suspect is not apprehended at the wheel and especially after hit-and-run incidents. Besides ethanol and water, alcoholic beverages contain trace amounts of many other low-molecular substances, known collectively as the congeners, which impart the characteristic smell and taste to the drink. Importantly, the congener profile can be used to identify a particular kind of alcoholic beverage. Forensic congener analysis entails making a qualitative and quantitative analysis of ethanol, methanol, n-propanol and the isomers of butanol in blood and urine from the apprehended driver and comparing the results with the known congener profile of the alcoholic beverage allegedly consumed after driving. Interpreting the results of congener analysis requires knowledge about the absorption, distribution and elimination pattern of the congener alcohols, including their oxidation and conjugation reactions, and any metabolic interactions with ethanol. Complications arise if drinks with widely different congener profiles are consumed or if the same beverage was ingested both before and after driving. Despite these limitations, congener analysis can furnish compelling evidence to challenge or support claims of drinking alcohol after driving. PMID:12627679

  13. Evidence for the use of organic carbon as the sorbing matrix in the modeling of PCB accumulation in phytoplankton

    SciTech Connect

    Skoglung, R.S.; Swackhamer, D.L.

    1999-05-01

    This report presents empirical evidence for the use of organic carbon as the sorbing matrix in the kinetic modeling of PCB accumulation in phytoplankton. A kinetic-based model was used to predict congener-specific bioaccumulation factors of PCBs in phytoplankton samples collected from Green Bay, Lake Michigan. These values were compared to the measured bioaccumulation factors, and the sum of the residuals was used to evaluate the model`s predictive quality. The sorbing matrix fraction (F{sub M}) that minimized the sum of residuals of the model was then solved by iteration. The appropriateness of using dry weight, organic carbon fraction, or lipid fractions as the sorbing matrix fraction was determined by measuring their correlation to the optimum F{sub M}. It was determined that the F{sub M} correlated best with the organic carbon fraction, and this correlation appeared to be independent of both the spatial and seasonal differences of the field samples.

  14. Potency of 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB 126) and 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD), to produce lake trout early life stage mortality

    SciTech Connect

    Zabel, E.W.; Peterson, R.E.; Cook, P.M.

    1995-12-31

    Toxic equivalency factors (TEFs) relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) have been determined in rainbow trout for certain polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) using endpoints of early life stage mortality. Rainbow trout are a convenient model fish species. However, one of the major species at risk in the Great Lakes, and the fish species most sensitive to TCDD, is lake trout. The current study sought to (1) determine in lake trout the toxic potency of 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB 126) in order to test the validity of generalizing TEFs across related species and (2) determine whether PCB 126 and TCDD act in an additive manner at a ratio similar to that found in feral lake trout eggs from the Great Lakes. Newly fertilized lake trout (Salvelinus namaycush) eggs were exposed to TCDD, PCB 126, or their combination at a ratio of 75:1, and sac fry mortality was used to determine toxic potencies. Signs of PCB 126 toxicity in lake trout early life stages were yolk-sac edema, multifocal hemorrhages, craniofacial malformations and mortality, identical to toxicity caused by TCDD. The TEF for PCB 126 was 0.003, which is similar to the TEF of 0.005 determined for rainbow trout early life stage mortality, suggesting that TEFs for the same endpoint are similar across related fish species. The dose-response curve for the congener mixture based on TCDD toxic equivalence was not significantly different from TCDD alone, suggesting that the congener combination acted additively to produce lake trout early life stage mortality.

  15. Regulation of pregnane-X-receptor, CYP3A and P-glycoprotein genes in the PCB-resistant killifish (Fundulus heteroclitus) population from New Bedford Harbor1

    PubMed Central

    Gräns, Johanna; Wassmur, Britt; Fernández-Santoscoy, María; Zanette, Juliano; Woodin, Bruce R.; Karchner, Sibel I.; Nacci, Diane E.; Champlin, Denise; Jayaraman, Saro; Hahn, Mark E.; Stegeman, John J.; Celander, Malin C.

    2015-01-01

    Killifish survive and reproduce in the New Bedford Harbor (NBH) in Massachusetts (MA), USA, a site severely contaminated with polychlorinated biphenyls (PCBs) for decades. Levels of 22 different PCB congeners were analyzed in liver from killifish collected in 2008. Concentrations of dioxin-like PCBs in liver of NBH killifish were ~400 times higher, and the levels of non-dioxin-like PCBs ~3000 times higher than in killifish from a reference site, Scorton Creek (SC), MA. The NBH killifish are known to be resistant to the toxicity of dioxin-like compounds and to have a reduced aryl hydrocarbon receptor (AhR) signaling response. Little is known about the responses of these fish to non-dioxin-like PCBs, which are at extraordinarily high levels in NBH fish. In mammals, some non-dioxin-like PCB congeners act through nuclear receptor 1I2, the pregnane-X-receptor (PXR). To explore this pathway in killifish, a PXR cDNA was sequenced and its molecular phylogenetic relationship to other vertebrate PXRs was determined. Killifish were also collected in 2009 from NBH and SC, and after four months in the laboratory they were injected with a single dose of either the dioxin-like PCB 126 (an AhR agonist) or the non-dioxin-like PCB 153 (a mammalian PXR agonist). Gills and liver were sampled three days after injection and transcript levels of genes encoding PXR, cytochrome P450 3A (CYP3A), P-glycoprotein (Pgp), AhR2 and cytochrome P450 1A (CYP1A) were measured by quantitative PCR. As expected, there was little effect of PCB exposure on mRNA expression of AhR2 or CYP1A in liver and gills of NBH fish. In NBH fish, but not in SC fish, there was increased mRNA expression of hepatic PXR, CYP3A and Pgp upon exposure to either of the two PCB congeners. However, basal PXR and Pgp mRNA levels in liver of NBH fish were significantly lower than in SC fish. A different pattern was seen in gills, where there were no differences in basal mRNA expression of these genes between the two populations

  16. Gender difference in walleye PCB concentrations persists following remedial dredging

    USGS Publications Warehouse

    Madenjian, Charles P.; Jude, David J.; Rediske, Richard R.; O'Keefe, James P.; Noguchi, George E.

    2009-01-01

    Eleven male walleyes (Sander vitreus) and 10 female walleyes from the Saginaw Bay (Lake Huron) population were caught during the spawning run at Dow Dam (Midland, Michigan) in the Tittabawassee River during April 1996, and individual whole-fish polychlorinated biphenyl (PCB) determinations were made. Total PCB concentrations averaged 7.95 and 3.17??mg/kg for males and females, respectively. As part of the Natural Resource Damage Assessment remediation process, contaminated sediments from the Saginaw River, the main tributary to Saginaw Bay, were removed during 2000 and 2001. Total PCB concentrations of 10 male and 10 female walleyes caught at Dow Dam during April 2007 averaged 1.58 and 0.55??mg/kg, respectively. Thus, dredging of the Saginaw River appeared to be effective in reducing PCB concentrations of Saginaw Bay adult walleyes, as both males and females decreased in PCB concentration by more than 80% between 1996 and 2007. However, the ratio of male PCB concentration to female PCB concentration did not decline between 1996 and 2007. This persistent gender difference in PCB concentrations was apparently due to a gender difference in habitat utilization coupled with a persistent spatial gradient in prey fish PCB concentrations from the Saginaw River to Lake Huron.

  17. Estimating whole-body fish PCB concentrations from fillet data

    SciTech Connect

    Rigg, D.; Hohreiter, D.; Strause, K.; Brown, M.; Barnes, C.

    1995-12-31

    A study was designed to assess a potentially cost-effective method for generating both types of data from single fish specimens. The method is based on the testable hypothesis that whole-body PCE concentrations are predictable from fillet PCB concentrations and fillet and whole-body lipid concentrations. The study involved the collection of small-mouth bass (Micropterus dolomieui) and carp (Cyprinus carpio) from several locations in the Kalamazoo River (Michigan) watershed to represent a range in PCB exposure. PCB and lipid concentrations were determined in aliquots of homogenized fillets and remaining carcasses. Wet-weight total PCB concentrations in carp ranged from 0.06 to 17 mg/kg in fillets, and from 0.11 to 14 mg/kg for remaining carcass; small-mouth bass ranged from 0.08 to 5.8 mg/kg in fillets, and from 0.21 to 13.2 mg/kg for remaining carcass. Whole-body PCB concentrations predicted using fillet PCB concentrations and fillet and carcass lipid concentrations accounted for 94% and 88% of the variability in measured whole-body small-mouth and whole-body carp concentrations, respectively. Predicted and measured whole-body PCB concentrations had a correlation of 91% for small-mouth bass, and 84% for carp. These results demonstrate that value of the lipid-based model in predicting whole-body PCB concentrations from measured fillet PCB concentrations and lipid concentrations in fillet and remaining carcass.

  18. Functionalized Congeners of P2Y1 Receptor Antagonists:

    SciTech Connect

    de Castro, Sonia; Maruoka, Hiroshi; Hong, Kunlun; Kilbey, II, S Michael; Costanzi, Stefano; Hechler, Béatrice; Gachet, Christian; Harden, T. Kendall; Jacobson, Kenneth A.

    2010-01-01

    The P2Y{sub 1} receptor is a prothrombotic G protein-coupled receptor (GPCR) activated by ADP. Preference for the North (N) ring conformation of the ribose moiety of adenine nucleotide 3',5'-bisphosphate antagonists of the P2Y{sub 1} receptor was established by using a ring-constrained methanocarba (a bicyclo[3.1.0]hexane) ring as a ribose substitute. A series of covalently linkable N{sup 6}-methyl-(N)-methanocarba-2'-deoxyadenosine-3',5'-bisphosphates containing extended 2-alkynyl chains was designed, and binding affinity at the human (h) P2Y{sub 1} receptor determined. The chain of these functionalized congeners contained hydrophilic moieties, a reactive substituent, or biotin, linked via an amide. Variation of the chain length and position of an intermediate amide group revealed high affinity of carboxylic congener 8 (K{sub i} 23 nM) and extended amine congener 15 (K{sub i} 132 nM), both having a 2-(1-pentynoyl) group. A biotin conjugate 18 containing an extended {epsilon}-aminocaproyl spacer chain exhibited higher affinity than a shorter biotinylated analogue. Alternatively, click coupling of terminal alkynes of homologous 2-dialkynyl nucleotide derivatives to alkyl azido groups produced triazole derivatives that bound to the P2Y{sub 1} receptor following deprotection of the bisphosphate groups. The preservation of receptor affinity of the functionalized congeners was consistent with new P2Y{sub 1} receptor modeling and ligand docking. Attempted P2Y{sub 1} antagonist conjugation to PAMAM dendrimer carriers by amide formation or palladium-catalyzed reaction between an alkyne on the dendrimer and a 2-iodopurine-derivatized nucleotide was unsuccessful. A dialkynyl intermediate containing the chain length favored in receptor binding was conjugated to an azide-derivatized dendrimer, and the conjugate inhibited ADP-promoted human platelet aggregation. This is the first example of attaching a strategically functionalized P2Y receptor antagonist to a PAMAM dendrimer to

  19. Multivariate modeling of PCB bioaccumulation in three-spined stickleback (Gasterosteus aculeatus)

    SciTech Connect

    Bavel, B. van; Andersson, P.; Wingfors, H.; Bergqvist, P.A.; Rappe, C.; Tysklind, M.; Aahgren, J.; Norrgren, L.

    1996-06-01

    Three-spined sticklebacks were exposed to 20 polychlorinated biphenyls (PCBs) through gastrointestinal intake. The PCBs, viz. 2,2{prime},3,4-TeCB, 2,2{prime},4,6{prime}-TeCB, 2,3,3{prime},5{prime}-TeCB, 2,3,4,4{prime}-TeCB, 2,3{prime},4,5{prime}-TeCB, 3,3{prime},4,5-TeCB, 2,2{prime},3,4{prime},6-PeCB, 2,2{prime},4,4{prime},5-PeCB, 2,2{prime},4,6,6{prime}-PeCB, 2,3,3{prime},5,6-PeCB, 2,3,4,4{prime},6-PeCB, 3,3{prime}4,4{prime}5-PeCB, 2,2{prime},3,4,5,6{prime}-HxCB, 2,2{prime},4,4{prime},5,5{prime}-HxCB, 3,3{prime},4,4{prime},5,5{prime}-HxCB, 2,2{prime},3,3{prime},4,5,6-HpCB, 2,2{prime},3,4,4{prime},6,6{prime}-HpCB, 2,2{prime},3,4{prime},5,6,6{prime}-HpCB, 2,3,3{prime},4,4{prime},5,6-HpCB, and 2,3,3{prime},4{prime},5,5{prime},6-HpCB, were selected by means of a full factorial design in combination with principal component analyses based on several physicochemical properties of tetra- through hepta-PCBs. After exposure to the training set, pooled samples of the sticklebacks were analyzed by GC-MS after lipid determination and cleanup using Florisil open-column chromatography. Bioaccumulation factors (BAFs) were calculated on a lipid basis by dividing the PCB concentrations in the fish by the respective concentrations in the feed. Higher chlorinated PCBs showed, in general, higher bioaccumulation than the lower chlorinated congeners. Polychlorinated biphenyls with vicinal hydrogens in the meta- and para-positions exhibited low bioaccumulation. Finally, 18 of the 20 measured BAFs were used to calculate a multivariate quantitative structure-activity relationship (QSAR) by means of partial least squares fitting to latent structures. By applying this QSAR, the bioaccumulation potentials of 136 nontested tetra- through hepta-PCB congeners were predicted.

  20. Direct Evidence for PCB Destruction in the Subtropical Troposphere by OH Radicals

    NASA Astrophysics Data System (ADS)

    Mandalakis, M.; Berresheim, H.; Stephanou, E.

    2003-04-01

    Although polychlorinated biphenyls (PCBs) production and use were banned by the mid-1970s, PCBs are ubiquitous pollutants in nearly all environmental compartments. Because of their high persistence and toxicity PCBs can pose toxic effects on animals and humans, decades after their release into the environment. It has been supported that warm temperatures at the tropical and subtropical regions of the earth favor the volatilization of PCBs, which are subsequently transported to colder areas of high latitude. This process, known as "global distillation effect", could cause an enhancement of PCB concentrations in the plant biomass and the marine mammals of Earth's polar regions. It has been experimentally established, that chemical reactions of PCBs with OH radicals might be the dominant loss processes in the atmosphere1. Nevertheless, PCBs atmospheric removal by OH radicals has never been positively demonstrated under real atmospheric conditions, mainly due to the difficulties to measure simultaneously the concentration of OH radicals and PCBs in the atmosphere. By applying elaborated sampling and analytical techniques2,3, under real atmospheric conditions, we achieved the simultaneous determination of OH radicals and PCBs congeners and demonstrated for the first time that PCB removal from the troposphere of subtropical regions is due to a large extent to reactions with OH radicals. References 1. Anderson, P. N. &Hites, R. A. OH radical reactions: The major removal pathway for polychlorinated biphenyls from the atmosphere. Environ. Sci. Technol. 30, 1756-1763 (1996). 2. Berresheim, H., Elste, T., Plass-Dülmer, C., Eisele, F. L. &Tanner, D. J. Chemical ionization mass spectrometer for long-term measurements of atmospheric OH and H2SO4. Int. J. Mass Spectrom. 202, 91-109 (2000). 3. Mandalakis, M., M. Tsapakis, and E.G. Stephanou, Optimization and application of high-resolution gas chromatography with ion trap tandem mass spectrometry to the determination of

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

    SciTech Connect

    Colciago, A.; Casati, L.; Mornati, O.; Vergoni, A.V.; Santagostino, A.; Celotti, F. Negri-Cesi, P.

    2009-08-15

    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. Impacts from PCB accumulation on amphibians inhabiting streams flowing from the Paducah Gaseous Diffusion Plant.

    PubMed

    DeGarady, C J; Halbrook, R S

    2003-11-01

    Contamination at the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky, has been under evaluation for many years. We studied amphibians in selected outfalls (drainage ditches) flowing from the PGDP to determine if PCBs were accumulating in their tissues and how this might affect local populations. We determined relative amphibian species richness and abundance among seven outfalls and three reference streams by listening to their calls during audio surveys. We also captured amphibians from each study site during the summers of 2000 and 2001 and analyzed their carcasses for PCBs (Aroclor 1260 and 34 congeners) and livers for ethoxyresorufin O-deethylase (EROD) activity, a biomarker of PCBs and other organic contamination. Ten species were heard across study sites, and abundance and richness at outfalls were similar to those observed at reference sites. However, there were significant differences in abundance (p = 0.001) and richness (p = 0.048) of amphibians between continuously flowing and intermittent outfalls. There were no significant differences in PCB concentrations (p = 0.113) in amphibians captured from study sites, although Aroclor 1260 concentrations tended to be higher in amphibians collected from one outfall (outfall 12) on the east side of the plant (x = 1260 microg/kg) compared with all other study sites (x = 489 microg/kg). EROD activity measured in the liver was not indicative of Aroclor 1260 concentrations in amphibians at the PGDP, and EROD did not differ by study site, species, age class, or gender. PCB concentrations measured in amphibians at the PGDP were similar to concentrations measured at reference sites and did not appear to negatively affect individual amphibians or abundance and richness. PMID:14708669

  3. PCDD/Fs, PCBs and PBDEs in zooplankton in the Baltic Sea - spatial and temporal shifts in the congener-specific concentrations.

    PubMed

    Peltonen, Heikki; Ruokojärvi, Päivi; Korhonen, Markku; Kiviranta, Hannu; Flinkman, Juha; Verta, Matti

    2014-11-01

    In the marine food-webs, zooplankton is a key element in the transfer of persistent organic pollutants to higher trophic levels. We determined the congener-specific concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in offshore zooplankton (size from 0.2 to 20mm) collected in 2001, 2002 and 2010 in the northern and central Baltic Sea. Of the PCDD/Fs, the concentrations of 2378-TCDF were from 18 to 47 and of 23478-PeCDF from 7.9 to 29 pg g(-1)fat and showed little temporal differences. However, 1234678-HpCDF and OCDF were abundant in 2001-2002 especially in the eastern Gulf of Finland (average concentrations 50 and 89 pg g(-1)fat, respectively). In 2010 the concentrations of these two congeners were lower, 29 and 30 pg g(-1)fat, respectively, but still substantially higher than in the other surveyed areas. The principal components analysis (PCA) supported that area-specific patterns in pollution strongly contributed to the congener profiles particularly in surface sediment and in sediment trap material, but even in zooplankton. The concentrations of the PCBs were highest in the Gulf of Finland and in the Bothnian Bay. The concentrations of most PCBs were somewhat lower in 2010 than in 2001-2002. Of the dioxin-like PCBs, the concentrations of PCB-77 were highest (271-572 pg g(-1)fat) but PCB-126 (32-113 pg g(-1)fat) contributed from 85% to 91% of the total toxicity of PCBs due to its higher toxic potency. Of the PBDEs, the BDE47 and BDE99 were the most abundant (concentrations from 1.2 to 4.6 and from 0.4 to 3.3 ng g(-1) fat, respectively). The concentrations of most PBDEs were lower in 2010 than in 2001/2002 except in the eastern Gulf of Finland. PMID:25113199

  4. Polychlorinated biphenyls PCB 153 and PCB 126 impair the glutamate-nitric oxide-cGMP pathway in cerebellar neurons in culture by different mechanisms.

    PubMed

    Llansola, Marta; Piedrafita, Blanca; Rodrigo, Regina; Montoliu, Carmina; Felipo, Vicente

    2009-08-01

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants present in human blood and milk. Exposure to PCBs during pregnancy and lactation leads to cognitive impairment in children. Perinatal exposure to PCB 153 or PCB 126 impairs the glutamate-nitric oxide-cGMP pathway in cerebellum in vivo and learning ability in adult rats. The aims of this work were: (1) to assess whether long-term exposure of primary cultures of cerebellar neurons to PCB 153 or PCB 126 reproduces the impairment in the function of the glutamate-nitric oxide-cGMP pathway found in rat cerebellum in vivo; (2) to provide some insight on the steps of the pathway affected by these PCBs; (3) to assess whether the mechanisms of interference of the pathway are different for PCB 126 and PCB 153. Both PCB 153 and PCB 126 increase basal levels of cGMP by different mechanisms. PCB 126 increases the amount of soluble guanylate cyclase while PCB 153 does not. PCB 153 reduces the amount of calmodulin while PCB 126 does not. Also both PCBs impair the function of the glutamate-nitric oxide-cGMP pathway by different mechanisms, PCB 153 impairs nitric oxide-induced activation of soluble guanylate cyclase and increase in cGMP while PCB 126 does not. PCB 126 reduces NMDA-induced increase in calcium while PCB 153 does not. When PCB 153 and PCB 126 exhibit the same effect, PCB 126 was more potent than PCB 153, as occurs in vivo. PMID:19526286

  5. 40 CFR 766.27 - Congeners and LOQs for which quantitation is required.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... substances containing predominantly chlorine atoms, only congeners totally chlorinated at the numbered positions need be quantified; for chemical substances containing predominantly bromine atoms, only...

  6. 40 CFR 766.27 - Congeners and LOQs for which quantitation is required.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... substances containing predominantly chlorine atoms, only congeners totally chlorinated at the numbered positions need be quantified; for chemical substances containing predominantly bromine atoms, only...

  7. 40 CFR 766.27 - Congeners and LOQs for which quantitation is required.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... substances containing predominantly chlorine atoms, only congeners totally chlorinated at the numbered positions need be quantified; for chemical substances containing predominantly bromine atoms, only...

  8. 40 CFR 766.27 - Congeners and LOQs for which quantitation is required.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... substances containing predominantly chlorine atoms, only congeners totally chlorinated at the numbered positions need be quantified; for chemical substances containing predominantly bromine atoms, only...

  9. 40 CFR 766.27 - Congeners and LOQs for which quantitation is required.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... substances containing predominantly chlorine atoms, only congeners totally chlorinated at the numbered positions need be quantified; for chemical substances containing predominantly bromine atoms, only...

  10. 40 CFR 761.274 - Reporting PCB concentrations in samples.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Reporting PCB concentrations in... Accordance with § 761.61(a)(2) § 761.274 Reporting PCB concentrations in samples. (a) Report all sample concentrations for non-liquid PCBs on a dry weight basis as micrograms of PCBs per gram of sample (ppm by...

  11. 40 CFR 761.274 - Reporting PCB concentrations in samples.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Reporting PCB concentrations in... Accordance with § 761.61(a)(2) § 761.274 Reporting PCB concentrations in samples. (a) Report all sample concentrations for non-liquid PCBs on a dry weight basis as micrograms of PCBs per gram of sample (ppm by...

  12. PCB (polychlorinated biphenyls) concentrations in Wilson Reservoir catfish, 1985

    SciTech Connect

    Dycus, D.L.; Lowery, D.R.

    1986-09-01

    TVA conducted a study during autumn 1984 to determine concentrations of a variety of contaminants in biota from Wilson and upper Pickwick Reservoirs. Several contaminants were detected, with polychlorinated biphenyls (PCB) levels in catfish from Wilson Reservoir of greatest interest. PCB concentrations in twenty-two of 45 catfish from Wilson equaled or exceeded the Food and Drug Administration (FDA) tolerance of 2.0 ..mu..g/g and the average of all 45 was 2.6 ..mu..g/g. Contamination was widespread and did not show any geographical relationship to an embayment on Wilson Reservoir (Fleet Hollow) known to have PCBs in the sediments. As a result of these findings, the Northwest Alabama Regional Health Department issued an official notice to retail markets in June 1985 to discontinue selling catfish from Wilson Reservoir. TVA initiated studies to determine if there were other areas on Wilson with PCB contaminated sediments or PCB discharges, and an annual catfish collection was started in autumn 1985 to determine the year-to-year trend in PCB levels. As a follow-up to earlier studies, analyses of catfish collected during autumn 1985 indicated substantial reductions in PCB concentrations. Only 4 of 36 catfish had PCB concentrations which equaled or exceeded 2.0 ..mu..g/g and the overall average was 1.0 ..mu..g/g. Statistical analyses indicated PCB concentrations decreased with increased distance from Fleet Hollow. Further monitoring is recommended for 2 more years.

  13. 40 CFR 761.269 - Sampling liquid PCB remediation waste.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sampling liquid PCB remediation waste... with § 761.61(a)(2) § 761.269 Sampling liquid PCB remediation waste. (a) If the liquid is single phase... liquid is multi-phasic, separate the phases, and collect and analyze a sample from each liquid...

  14. 40 CFR 761.269 - Sampling liquid PCB remediation waste.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sampling liquid PCB remediation waste... with § 761.61(a)(2) § 761.269 Sampling liquid PCB remediation waste. (a) If the liquid is single phase... liquid is multi-phasic, separate the phases, and collect and analyze a sample from each liquid...

  15. 40 CFR 761.269 - Sampling liquid PCB remediation waste.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Sampling liquid PCB remediation waste... with § 761.61(a)(2) § 761.269 Sampling liquid PCB remediation waste. (a) If the liquid is single phase... liquid is multi-phasic, separate the phases, and collect and analyze a sample from each liquid...

  16. 40 CFR 761.269 - Sampling liquid PCB remediation waste.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Sampling liquid PCB remediation waste... with § 761.61(a)(2) § 761.269 Sampling liquid PCB remediation waste. (a) If the liquid is single phase... liquid is multi-phasic, separate the phases, and collect and analyze a sample from each liquid...

  17. 40 CFR 761.269 - Sampling liquid PCB remediation waste.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Sampling liquid PCB remediation waste... with § 761.61(a)(2) § 761.269 Sampling liquid PCB remediation waste. (a) If the liquid is single phase... liquid is multi-phasic, separate the phases, and collect and analyze a sample from each liquid...

  18. 40 CFR 761.2 - PCB concentration assumptions for use.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... assume that a capacitor manufactured prior to July 2, 1979, whose PCB concentration is not established contains ≥500 ppm PCBs. Any person may assume that a capacitor manufactured after July 2, 1979, is non-PCB (i.e., <50 ppm PCBs). If the date of manufacture is unknown, any person must assume the...

  19. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... FOOD-PACKAGING MATERIAL Tolerances for Unavoidable Poisonous or Deleterious Substances § 109.30...-contaminated animal feed. In addition, a significant percentage of paper food-packaging materials contain PCB's which may migrate to the packaged food. The source of PCB's in paper food-packaging materials...

  20. Investigating links between polychlorinated biphenyl (PCB) exposure and thymic involution and thymic cysts in harbour porpoises (Phocoena phocoena).

    PubMed

    Yap, Xinli; Deaville, Rob; Perkins, Matthew W; Penrose, Rod; Law, Robin J; Jepson, Paul D

    2012-10-01

    The associations between polychlorinated biphenyls (PCBs) exposure and involution of lymphoid tissue and development of epithelial-lined cysts in the thymus of UK-stranded harbour porpoises (Phocoena phocoena) (n=170) were tested. Percentage of thymic lymphoid tissue (%TLT) was histologically quantified. Multiple regression analyses (n=169) demonstrated significant positive correlation between %TLT and nutritional status (p<0.001) and significant negative association between %TLT and onset of sexual maturity (p<0.001). However, in a subgroup of porpoises with total PCB levels above a proposed threshold of toxicity (>17mg/kg lipid weight) (n=109), the negative association between %TLT (as dependent variable) and summed blubber concentrations of 25 chlorobiphenyl congeners (∑25CBs) remained significant (p<0.01) along with nutritional status (p<0.001) and onset of sexual maturity (p<0.001). These results suggest PCB-induced immuno suppression may be occurring in harbour porpoises in UK waters but only at concentrations that exceed proposed toxicity thresholds for marine mammals. In contrast, development of thymic cysts appears predominantly age-related. PMID:22917837

  1. PCDD/F and PCB water column partitioning examination using natural organic matter and black carbon partition coefficient models.

    PubMed

    Howell, Nathan L; Rifai, Hanadi S

    2016-04-01

    A 9-year water dataset from the Houston Ship Channel (HSC) was analyzed to understand partitioning in polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/Fs). Total PCBs had more mass as dissolved (74%) whereas total PCDD/Fs did not (11%). Generally, the limited number of PCDD/Fs (only 2378 substituted) explained these differences though differences in chemical behavior beyond log K ow also likely influence partitioning. The particular fractionation seen in the HSC also seemed related to a wide variation in particulate organic carbon (POC)/dissolved organic carbon (DOC) ratio (0.42-180%). Published and unaltered linear free energy and linear solvation energy relationships for DOC, POC, and particulate black carbon (BC) resulted in predictions that were at best 27% (PCB) and 25% root-mean-square error (RMSE) (PCDD/F) partition fraction compared to observed (using estimated BC/POC fractions of 10 and 25%, respectively). These results show, at least in light of the uncertainties in this data (e.g., precise fraction of BC), that a 25% accuracy in model prediction of operationally dissolved or suspended fraction for any one PCB or PCDD/F congener is the best prediction that may be expected. It is therefore recommended that site-specific data be used to calibrate most any water column-partitioning model if it is to be expected to describe what actually occurs in field conditions. PMID:26614453

  2. Photocatalytic dechlorination of PCB 138 using leuco-methylene blue and visible light; reaction conditions and mechanisms.

    PubMed

    Izadifard, Maryam; Langford, Cooper H; Achari, Gopal

    2010-09-15

    A study of dechlorination of PCB 138, under visible light employing methylene blue (MB) and triethylamine (TEA) in acetonitrile/water has been conducted to investigate the details of the mechanism of dechlorination and to determine the efficiency of the process for this representative congener. Two other amines, N-methyldiethanolamine (MEDA) and (triethanolamine) TEOA also replaced TEA and two other solvents, methanol and ethanol replacing acetonitrile were examined for effects on reaction rates. The results show that PCB 138 can be dechlorinated efficiently in this photocatalytic reaction. Clarifying ambiguities in several previous reports, the reduced form of MB, leuco-methylene blue (LMB) was identified as responsible for the photoreaction with its excited state transferring an electron to PCBs; oxidized LMB (i.e. MB) is reduced back to LMB by the excess amine present. The reaction depends on a cycle driven by the amine as a sacrificial electron donor. MEDA proved to be the most efficient electron donor; apparently in consequence of the most favourable steady state concentration of LMB. Methanol and ethanol may be used to replace acetonitrile with little change in the efficiency of the reaction. PMID:20542375

  3. Persistent organic pollutants (PCB, DDT, HCH, HCB & BDE) in eels (Anguilla anguilla) in Scotland: current levels and temporal trends.

    PubMed

    Macgregor, Kenneth; Oliver, Ian W; Harris, Lynsay; Ridgway, Ian M

    2010-07-01

    Eels are an ideal biomonitor for persistent organic pollutants (POPs) because of their high lipid content, longevity and tendency to remain within a defined range during their freshwater life phase. This study investigated concentrations of POPs in eels (Anguilla anguilla) from 30 sites across Scotland, including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (BDEs), DDT (and metabolites), hexachlorocyclohexanes (alpha, beta, gamma-HCH), hexachlorobenzene (HCB), hexachlorobutadiene (HCBD) and pentachlorobenzene. Despite its EU-wide ban approximately 30 years ago, DDT and its derivatives were detected in almost all samples. PCB 153 and 138 were the most widely detected PCB congeners, while BDE 47 was the dominant BDE. Pentachlorobenzene was not detected, while HCBD was detected once only. alpha-HCH, beta-HCH and HCB concentrations were very low (generally <3 microg/kg or below detection). When compared with 1986 and 1995 data, the results revealed considerable decreases in p,p'-DDE concentrations. More drastic reductions were evident for gamma-HCH, reflecting the tightening restrictions on pesticide use imposed over the previous decades. PMID:20471146

  4. Expression and function of ryanodine receptor related pathways in PCB tolerant Atlantic killifish (Fundulus heteroclitus) from New Bedford Harbor, MA, USA

    PubMed Central

    Fritsch, Erika B.; Stegeman, John J.; Goldstone, Jared V.; Nacci, Diane E.; Champlin, Denise; Jayaraman, Saro; Connon, Richard E.; Pessah, Isaac N.

    2015-01-01

    Atlantic killifish (Fundulus heteroclitus) thrive in New Bedford Harbor (NBH), MA, highly contaminated with polychlorinated biphenyls (PCBs). Resident killifish have evolved tolerance to dioxin-like (DL) PCBs, whose toxic effects through the aryl hydrocarbon receptor (AhR) are well studied. In NBH, non-dioxin like PCBs (NDL PCBs), which lack activity toward the AhR, vastly exceed levels of DL congeners yet how killifish counter NDL toxic effects has not been explored. In mammals and fish, NDL PCBs are potent activators of ryanodine receptors (RyR), Ca2+ release channels necessary for a vast array of physiological processes. In the current study we compared the expression and function of RyR related pathways in NBH killifish with killifish from the reference site at Scorton Creek (SC, MA). Relative to the SC fish, adults from NBH displayed increased levels of skeletal muscle RyR1 protein, and increased levels of FK506-binding protein 12 kDa (FKBP12), an accessory protein essential for NDL PCB-triggered changes in RyR channel function. In accordance with increased RyR1 levels, NBH killifish displayed increased maximal ligand binding, increased maximal response to Ca2+ activation and increased maximal response to activation by the NDL PCB congener PCB 95. Compared to SC, NBH embryos and larvae had increased levels of mtor and ryr2 transcripts at multiple stages of development, and generations, while levels of serca2 were decreased at 9 days post-fertilization in the F1 and F2 generations. These findings suggest that there are compensatory and heritable changes in RyR mediated Ca2+ signaling proteins or potential signaling partners in NBH killifish. PMID:25546006

  5. Comparison of PCB and trace metal bioaccumulation in the blue mussel, Mytilus edulis, and the ribbed mussel, Modiolus demissus, in New Bedford Harbor, Massachusetts

    SciTech Connect

    Nelson, W.G.; Bergen, B.J.; Cobb, D.J.

    1995-03-01

    The accumulation of PCBs and trace metals was compared at 14-d intervals between two filter-feeding bivalves, the blue mussel, Mytilus edulis, and the ribbed mussel, Modiolus demissus, after deployment in New Bedford Harbor, Massachusetts, for up to 56 d. Contaminant uptake in deployed organisms also was compared with indigenous ribbed mussels. Significant mortality occurred in blue mussels after 28 d, when water temperatures exceeded 25 C. Therefore, tissue-residue comparisons between species are presented only up to day 28, while those between deployed and indigenous ribbed mussels continue to day 56. Results indicated that total PCB tissue residues and congener distributions were not statistically different in the two mussel species on day 28. Total PCB concentrations in both deployed mussel species reached approximately 30 {mu}g g{sup {minus}1} dry weight by day 28. Additionally, total PCB concentrations and congener distributions in the deployed ribbed mussels were not statistically different from the indigenous ribbed mussels on day 28, demonstrating that steady state was attained within 28 d. With respect to metal uptake, no single accumulation pattern occurred for the eight metals quantified. After 28 d, lead, cadmium, and iron concentrations in deployed blue and ribbed mussels were statistically similar. However, nickel and zinc accumulations were significantly greater in the blue mussels, and copper, chromium, and manganese were accumulated to significantly higher concentrations in the ribbed mussels. The comparison between the ribbed mussels indicated that cadmium and lead concentrations were significantly higher in indigenous than in deployed mussels after 28 d.

  6. PCB remediation in schools: a review.

    PubMed

    Brown, Kathleen W; Minegishi, Taeko; Cummiskey, Cynthia Campisano; Fragala, Matt A; Hartman, Ross; MacIntosh, David L

    2016-02-01

    Growing awareness of polychlorinated biphenyls (PCBs) in legacy caulk and other construction materials of schools has created a need for information on best practices to control human exposures and comply with applicable regulations. A concise review of approaches and techniques for management of building-related PCBs is the focus of this paper. Engineering and administrative controls that block pathways of PCB transport, dilute concentrations of PCBs in indoor air or other exposure media, or establish uses of building space that mitigate exposure can be effective initial responses to identification of PCBs in a building. Mitigation measures also provide time for school officials to plan a longer-term remediation strategy and to secure the necessary resources. These longer-term strategies typically involve removal of caulk or other primary sources of PCBs as well as nearby masonry or other materials contaminated with PCBs by the primary sources. The costs of managing PCB-containing building materials from assessment through ultimate disposal can be substantial. Optimizing the efficacy and cost-effectiveness of remediation programs requires aligning a thorough understanding of sources and exposure pathways with the most appropriate mitigation and abatement methods. PMID:25994266

  7. Interim Basis for PCB Sampling and Analyses

    SciTech Connect

    BANNING, D.L.

    2001-01-18

    This document was developed as an interim basis for sampling and analysis of polychlorinated biphenyls (PCBs) and will be used until a formal data quality objective (DQO) document is prepared and approved. On August 31, 2000, the Framework Agreement for Management of Polychlorinated Biphenyls (PCBs) in Hanford Tank Waste was signed by the US. Department of Energy (DOE), the Environmental Protection Agency (EPA), and the Washington State Department of Ecology (Ecology) (Ecology et al. 2000). This agreement outlines the management of double shell tank (DST) waste as Toxic Substance Control Act (TSCA) PCB remediation waste based on a risk-based disposal approval option per Title 40 of the Code of Federal Regulations 761.61 (c). The agreement calls for ''Quantification of PCBs in DSTs, single shell tanks (SSTs), and incoming waste to ensure that the vitrification plant and other ancillary facilities PCB waste acceptance limits and the requirements of the anticipated risk-based disposal approval are met.'' Waste samples will be analyzed for PCBs to satisfy this requirement. This document describes the DQO process undertaken to assure appropriate data will be collected to support management of PCBs and is presented in a DQO format. The DQO process was implemented in accordance with the U.S. Environmental Protection Agency EPA QAlG4, Guidance for the Data Quality Objectives Process (EPA 1994) and the Data Quality Objectives for Sampling and Analyses, HNF-IP-0842, Rev. 1 A, Vol. IV, Section 4.16 (Banning 1999).

  8. Interim Basis for PCB Sampling and Analyses

    SciTech Connect

    BANNING, D.L.

    2001-03-20

    This document was developed as an interim basis for sampling and analysis of polychlorinated biphenyls (PCBs) and will be used until a formal data quality objective (DQO) document is prepared and approved. On August 31, 2000, the Framework Agreement for Management of Polychlorinated Biphenyls (PCBs) in Hanford Tank Waste was signed by the U.S. Department of Energy (DOE), the Environmental Protection Agency (EPA), and the Washington State Department of Ecology (Ecology) (Ecology et al. 2000). This agreement outlines the management of double shell tank (DST) waste as Toxic Substance Control Act (TSCA) PCB remediation waste based on a risk-based disposal approval option per Title 40 of the Code of Federal Regulations 761.61 (c). The agreement calls for ''Quantification of PCBs in DSTs, single shell tanks (SSTs), and incoming waste to ensure that the vitrification plant and other ancillary facilities PCB waste acceptance limits and the requirements of the anticipated risk-based disposal approval are met.'' Waste samples will be analyzed for PCBs to satisfy this requirement. This document describes the DQO process undertaken to assure appropriate data will be collected to support management of PCBs and is presented in a DQO format. The DQO process was implemented in accordance with the U.S. Environmental Protection Agency EPA QA/G4, Guidance for the Data Quality Objectives Process (EPA 1994) and the Data Quality Objectives for Sampling and Analyses, HNF-IP-0842, Rev. 1A, Vol. IV, Section 4.16 (Banning 1999).

  9. EMC in power electronics and PCB design

    NASA Astrophysics Data System (ADS)

    Zhu, Chentian

    This dissertation consists of two parts. Part I is about Electromagnetic Compatibility (EMC) in power electronics and part II is about the Maximum Radiated Electromagnetic Emissions Calculator (MREMC), which is a software tool for EMC in printed circuit board (PCB) design. Switched-mode power converters can be significant sources of electromagnetic fields that interfere with the proper operation of nearby circuits or distant radio receivers. Part I of this dissertation provides comprehensive and organized information on the latest EMC developments in power converters. It describes and evaluates different technologies to ensure that power converters meet electromagnetic compatibility requirements. Chapters 2 and 3 describe EMC noise sources and coupling mechanisms in power converters. Chapter 4 reviews the measurements used to characterize and troubleshoot EMC problems. Chapters 5 -- 8 cover passive filter solutions, active filter solutions, noise cancellation methods and reduced-noise driving schemes. Part II describes the methods used, calculations made, and implementation details of the MREMC, which is a software tool that allows the user to calculate the maximum possible radiated emissions that could occur due to specific source geometries on a PCB. Chapters 9 -- 13 covers the I/O coupling EMI algorithm, Common-mode EMI algorithm, Power Bus EMI algorithm and Differential-Mode EMI algorithm used in the MREMC.

  10. Predicting and controlling downwind concentrations of PCB from surface impoundments

    SciTech Connect

    Angiola, A.J.; Soden, J.M.

    1982-01-01

    Over 227,000 kv of PCB were discharged into the Hudson River from two capacitor manufacturing plants at Fort Edward and Hudson Falls, New York. Much of the discharged PCB was absorbed by the bottom sediments of the river and accumulated behind the Fort Edward Dam. A large amount of the contaminated sediments migrated dowstream when the dam was removed. An effort has been made to dredge PCB-contaminated sediments from the Upper Hudson River and to deposit those sediments in a secure containment site. Part of this project was an air quality impact analysis which addressed the effect of PCB volatilization from the proposed containment site on ambient 24-hour concentrations of PCB downwind of the site. An estimate of the volatilization rate was made and a dispersion modeling analysis was performed in order to calculate the potential impact on residences. 4 references, 1 table.

  11. Egg incubation position affects toxicity of air cell administered PCB 126 (3,3?4,4?,5- pentachlorobiphenyl) in chicken (Gallus domesticus) embryos

    USGS Publications Warehouse

    McKernan, M.A.; Rattner, B.A.; Hale, R.C.; Ottinger, M.A.

    2007-01-01

    The avian egg is used extensively for chemical screening and determining the relative sensitivity of species to environmental contaminants (e.g., metals, pesticides, polyhalogenated compounds). The effect of egg incubation position on embryonic survival, pipping, and hatching success was examined following air cell administration of polychlorinated biphenyl (PCB) congener 126 (3,3',4,4',5-pentachlorobiphenyl [PCB 126]; 500?2,000 pg/g egg) on day 4 of development in fertile chicken (Gallus gallus) eggs. Depending on dose, toxicity was found to be up to nine times greater in vertically versus horizontally incubated eggs. This may be due to enhanced embryonic exposure to the injection bolus in vertically incubated eggs compared to more gradual uptake in horizontally incubated eggs. Following air cell administration of PCB 126, horizontal incubation of eggs may more closely approximate uptake and toxicity that has been observed with naturally incorporated contaminants. These data have implications for chemical screening and use of laboratory data for ecological risk assessments.

  12. PCB in tissue concentrations in great blue heron occupying a Superfund site: Risk assessment implications

    SciTech Connect

    Halbrook, R.S.; Brewer, R.; Mitchell, J.M.

    1994-12-31

    Using existing ambient concentrations of chemicals and conservative assumptions, preliminary risk assessment has indicated that piscivorous wildlife along the Clinch River adjacent to the Oak Ridge Reservation (ORR), Oak Ridge, TN are potentially at risk from exposure to PCBs. Total PCB concentrations in great blue heron egg and chick liver tissue (7.69 {mu}g/g and 1.91 {mu}g/g, respectively) collected from a tributary to the Clinch River passing through the ORR, were significantly greater than concentrations in egg and chick liver tissue (1.24 {mu}g/g and 0.71 {mu}g/g, respectively) collected off the ORR. Mono and non-ortho CB congeners also were greater in heron tissues collected on the ORR compared to those collected off the ORR. Reproductive parameters (eggs/nest and chicks/nest) were not significantly different between locations. These data indicate that herons nesting on the ORR are exposed to PCBs, however, concentrations are insufficient to illicit a detectable adverse reproductive response in this species. Risk assessment implications are that piscivorous species utilizing habitats on the ORR are accumulating environmental contaminants greater than back ground concentrations for this region, however, only the most sensitive species are probably adversely effected. Continued monitoring will provide base-line data for evaluating natural resource damages and remediation decisions.

  13. Toxicity and fetotoxicity of TCDD, TCDF and PCB isomers in rhesus macaques (Macaca mulatta)

    SciTech Connect

    McNulty, W.P.

    1985-05-01

    In rhesus macaques (Macaca mulatta), consumption of food containing commercial polychlorinated biphenyl (PCB) mixtures, some pure polychlorobiphenyl congeners, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and 2,3,7,8-tetrachlorodibenzofuran (TCDF) caused the same clinical toxic manifestations and histopathologic lesions, although the potencies of the toxicants covered a range of five orders of magnitude. Recovery from poisoning by 3,4,3',4'-tetrachlorobiphenyl (34TCB) or TCDF was rapid, whereas recovery from poisoning by Aroclor 1242, 3,4,5,3',4',5'-hexachlorobiphenyl (345HCB), or TCDD was protracted, if it occurred at all. 34TCB did not appreciably accumulate in body fat, but the level of 345HCB in fat rose steadily during ingestion. Among the symmetrical tetra- and hexachlorobiphenyl isomers tested, subacute oral toxicity could be demonstrated only for those without ortho chlorine substitutions. The principal demonstrable histopathological lesions, bone marrow excepted, were metaplasias in some specialized epithelial structures, such as sebaceous glands, nail beds, gastric mucosa, ameloblast, and thymic corpuscles. These changes were interpreted as toxicant-induced, reversible redirection of differentiation. this aberration was wholly reversible. TCDD and 34TCB caused abortions when given in one or a few oral doses early in pregnancy. At the total doses used (1 or 5 g/kg of body weight for TCDD, 3 or 0.6 mg/kg of body weight for 34TCB), maternal toxicity was frequently apparent subsequent to the abortion.

  14. Waste incineration: estimation of the workers' internal exposure to PCB, PAH chlorophenols and other relevant agents

    NASA Astrophysics Data System (ADS)

    Angerer, Juergen; Heinzow, B.; Reimann, D. O.; Knorz, W.; Lehnert, G.

    1993-03-01

    Fifty-four persons occupied in a municipal waste incinerator were examined with respect to their internal exposure to organic substances which are possibly produced during pyrolysis of organic matter. For this purpose the levels of benzene of blood, polychlorinated biphenyls (PCB) and hexachlorobenzene (HCB) in plasma as well as mono- (MCP), di- (DCP), tri- (TCP), tetra- (TECP) and pentachlorophenols (PCP) and hydroxypyrene in urine have been determined. Four hundred thirty-one men and women were examined for control purposes. Statistical significantly higher values for the workers were found for the excretion of hydroxypyrene 2,5/2,4-DCP, 2,4,5 TCP, and for the HCB level in plasma. For the concentrations of 4-MCP and 2,3,4,6-2,3,5,6-TECP the controls had significantly higher concentrations in urine than the workers in the incineration plant. No significant differences between workers and controls were detected with respect to benzene in blood, 2,4,6-TCP and PCP in urine, and to the levels of PCP congeners in plasma. The elevated levels of hydroxypyrene, 2,4-/2,5 DCP, 2,4,5-TCP, and HCB in biological material may be related to the incineration of the waste. These elevations, however, are very small and attract attention more from the environmental than from the occupational point of view.

  15. Analytical approaches for the determination of PCB metabolites in blood: a review.

    PubMed

    Quinete, Natalia; Schettgen, Thomas; Bertram, Jens; Kraus, Thomas

    2014-10-01

    Polychlorinated biphenyls (PCBs) are among the most ubiquitous pollutants in the environment, and their metabolism leads to the formation of hydroxylated PCBs (OH-PCBs) and methyl sulfone PCBs (MeSO2-PCBs). These metabolites are generally more hydrophilic than the parent compound, and therefore are more easily eliminated from the body. However, some congeners have been shown to be strongly retained in human blood, binding to transthyretin with an affinity that is, in general, greater than that of the natural ligand thyroxin itself, which could result in toxicological effects, particularly on the thyroid system. Currently available analytical methods require, in general, extensive sample preparation, which includes a series of time-consuming and low-throughput liquid-liquid and back extractions, evaporations, several cleanup steps, and in some cases, derivatization prior to analysis by gas chromatography (GC) or liquid chromatography (LC) coupled with mass spectrometry (MS). Recent developments in the use of LC coupled with tandem MS (MS/MS) have brought some improvements in terms of sample preparation for the determination of PCB metabolites in blood, although there are still possibilities for continued development. The selected literature has evidenced few studies of LC-MS/MS-based methods, a lack of analytical standards, nonassessment of lower-chlorinated OH-PCBs, and scarce attention to MeSO2-PCBs in blood. This review aims to evaluate critically the currently available analytical methods for determination of OH-PCBs and MeSO2-PCBs in blood. PMID:24908411

  16. Congener specific biotransformation and bioaccumulation of PCDDs and PCDFs from fly ash in fish

    SciTech Connect

    Sijm, D.T.H.M.; Opperhuizen, A. . Research Inst. of Toxicology, Environmental Chemistry Group); Wever, H. . Dept. of Environmental and Toxicological Chemistry)

    1993-10-01

    Biotransformation may be responsible for the lack of bioaccumulation of a number of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Goldfish (Carassius auratus) that were exposed to PCDDs and PCDFs, and piperonylbutoxide (PBO) in water bioconcentrated significantly more congeners than goldfish exposed to PCDDs and PCDFs only. Monooxygenase activity, which is responsible for the oxidation of specific PCDD and PCDF congeners in untreated fish, was inhibited by fish treated with PBO. In the PBO-treated group and in the control group, congeners with all lateral positions substituted were found. Congeners that lack chlorine substitution on one or more of the lateral positions substituted were found. Congeners that lack chlorine substitution on one or more of the lateral (2,3,7,8) positions and congeners that have all lateral positions chlorinated were found only in PBO-treated fish. Congeners that have at least one free lateral position were therefore assumed to be biotransformed. There was no relationship between the octanol/water partition coefficient and biotransformed. There was no relationship between the octanol/water partition coefficient and biotransformation of the PCDDs and PCDFs. No limitation of uptake for higher chlorinated PCDD and PCDF congeners was found.

  17. Toxicokinetics of Polybrominated Diphenyl Ether Congeners 47, 99, 100, and 153 in Mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The congener profiles of polybrominated diphenyl ethers (PBDEs) in biota samples are dominated by PBDE congeners 47, 99, 100, 153, and 154; all of which are components of the commercial pentaBDE mixtures commonly used in a variety of flammable consumer products. Very little information is available...

  18. ELECTRONIC ELASTICITY-TOXICITY RELATIONSHIPS FOR POLYCHLORINATED DIBENZO-P-DIOXIN CONGENERS. (R826166)

    EPA Science Inventory

    SCF-MO computations have been performed on tetra- to octa-chlorinated dibenzo-p-dioxin congeners (PCDD) using an MNDO-PM3 Hamiltonian. Qualitative relationships were developed between empirical, international-toxic equivalence factors for PCDD congeners and their relati...

  19. SENSITIVITY OF ADENOSINE TRIPHOSPHATASE IN DIFFERENT BRAIN REGIONS TO POLYCHLORINATED BIPHENYL CONGENERS

    EPA Science Inventory

    Polychlorinated biphenyl (PCBs) mixtures contain a number of different congeners, some of which have been proposed to be neuroactive. Recent studies have suggested that ortho-substituted PCBs may be neuroactive, while "dioxin-like" non-ortho-substituted congeners are not. This st...

  20. Sexual difference in PCB concentrations of coho salmon (Oncorhynchus kisutch)

    USGS Publications Warehouse

    Madenjian, Charles P.; Schrank, Candy S.; Begnoche, Linda J.; Elliott, Robert F.; Quintal, Richard T.

    2010-01-01

    We determined polychlorinated biphenyl (PCB) concentrations in 35 female coho salmon (Oncorhynchus kisutch) and 60 male coho salmon caught in Lake Michigan (Michigan and Wisconsin, United States) during the fall of 1994 and 1995. In addition, we determined PCB concentrations in the skin-on fillets of 26 female and 19 male Lake Michigan coho salmon caught during the fall of 2004 and 2006. All coho salmon were age-2 fish. These fish were caught prior to spawning, and therefore release of eggs could not account for sexual differences in PCB concentrations because female coho salmon spawn only once during their lifetime. To investigate whether gross growth efficiency (GGE) differed between the sexes, we applied bioenergetics modeling. Results showed that, on average, males were 19% higher in PCB concentration than females, based on the 1994–1995 dataset. Similarly, males averaged a 20% higher PCB concentration in their skin-on fillets compared with females. According to the bioenergetics modeling results, GGE of adult females was less than 1% higher than adult male GGE. Thus, bioenergetics modeling could not explain the 20% higher PCB concentration exhibited by the males. Nonetheless, a sexual difference in GGE remained a plausible explanation for the sexual difference in PCB concentrations.

  1. Inhalation of Polychlorinated Biphenyls (PCB) Produces Hyperactivity in Rats.

    PubMed

    Lombardo, John P; Berger, David F; Hunt, Anne; Carpenter, David O

    2015-01-01

    Attention deficit hyperactivity disorder (ADHD) is a serious behavioral syndrome seen in children, and more common in males than females. There is increasing evidence that prenatal and/or early life exposure to persistent organic pollutants (POP) such as polychlorinated biphenyls (PCB) is associated with increased risk of ADHD occurrence. While PCB exposure is usually attributed to ingestion of contaminated food, recent reports of elevated PCB concentrations in indoor air, especially in schools, raised concern regarding inhalation as an important route of exposure to PCB with consequent effects on neurobehavior. The effects of exposure to air contaminated with Aroclor 1248 or contaminated sediment (SED) from the St. Lawrence River were examined on operant behavior of male and female Sprague-Dawley rats. Data showed that relative to controls, vapor-phase inhalation of PCB, whether from blowing air over Aroclor 1248 or from blowing air over sediment contaminated with PCB, resulted in hyperactivity and impatience in rats, more pronounced in males than females. These results are consistent with the hypothesis that inhalation of PCB may contribute to behavioral abnormalities in children. PMID:26398098

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

    PubMed

    Fujiwara, K

    1975-09-01

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

  3. Spatial patterns in PCB concentrations of Lake Michigan lake trout

    USGS Publications Warehouse

    Madenjian, Charles P.; DeSorcie, Timothy J.; Stedman, Ralph M.; Brown, Edward H., Jr.; Eck, Gary W.; Schmidt, Larry J.; Hesselberg, Robert J.; Chernyak, Sergei M.; Passino-Reader, Dora R.

    1999-01-01

    Most of the PCB body burden in lake trout (Salvelinus namaycush) of the Great Lakes is from their food. PCB concentrations were determined in lake trout from three different locations in Lake Michigan during 1994–1995, and lake trout diets were analyzed at all three locations. The PCB concentrations were also determined in alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax), bloater (Coregonus hoyi), slimy sculpin (Cottus cognatus), and deepwater sculpin (Myoxocephalus thompsoni), five species of prey fish eaten by lake trout in Lake Michigan, at three nearshore sites in the lake. Despite the lack of significant differences in the PCB concentrations of alewife, rainbow smelt, bloater, slimy sculpin, and deepwater sculpin from the southeastern nearshore site near Saugatuck (Michigan) compared with the corresponding PCB concentrations from the northwestern nearshore site near Sturgeon Bay (Wisconsin), PCB concentrations in lake trout at Saugatuck were significantly higher than those at Sturgeon Bay. The difference in the lake trout PCB concentrations between Saugatuck and Sturgeon Bay could be explained by diet differences. The diet of lake trout at Saugatuck was more concentrated in PCBs than the diet of Sturgeon Bay lake trout, and therefore lake trout at Saugatuck were more contaminated in PCBs than Sturgeon Bay lake trout. These findings were useful in interpreting the long-term monitoring series for contaminants in lake trout at both Saugatuck and the Wisconsin side of the lake.

  4. Health effects of chronic exposure to polychlorinated dibenzo-P-dioxins (PCDD), dibenzofurans (PCDF) and coplanar PCB (Co-PCB) of municipal waste incinerator workers.

    PubMed

    Kitamura, K; Kikuchi, Y; Watanabe, S; Waechter, G; Sakurai, H; Takada, T

    2000-07-01

    A national survey of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in emission gases from the municipal waste incinerators in 1997 revealed that the Nose Bika Center was heavily contaminated by PCDF. Ninety-four workers underwent a physical examination, and blood biochemistry, lymphocyte marker, and NK activity studies were carried out, along with blood dioxin measurements. Information on working history, life-style, and dietary habits was obtained by questionnaire and interview. The blood dioxin levels were as follows. The median TEQ of dioxins was 39.7 pg I-TEQ/g lipid, and the range was 13.3 to 805.8. The median 2,3,7,8-TCDD concentration was 3.9 pg TEQ/g lipid, and the range was <1 pg TEQ/g lipid (one case) to 13.4 pg TEQ/g lipid. The median TEQ of coplanar PCB was 10.8 pg I-TEQ/g lipid, and the range was 3.1 to 54.2 pg TEQ/g lipid. The congener-specific distribution was quite similar to that in soil around incinerator and waste in the factory. The relationship between dioxin concentrations and work history in the factory showed that the fluidized incinerator and fly ash treatment areas were high-risk work areas. Correlation analyses between body burden, PCDD/PCDF TEQ, Co-PCB TEQ and various laboratory data showed significant positive correlations between dioxin levels and GGT, total protein, uric acid and calcium, and a negative correlation with Fe. However, these correlations disappeared as a result of multivariate analysis adjusted for age, smoking status, and alcohol drinking. Increased NK activity and lower response to PHA stimulation remained significant even after adjusting for age. History of hyperlipidemia and allergy had significantly increased odds ratios. A study on the risk to other workers in the same type of incinerators is under way. Health effects of chronic exposure mainly to PCDF will be clarified by follow-up. PMID:10959609

  5. 40 CFR 761.358 - Determining the PCB concentration of samples of waste.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Determining the PCB concentration of..., DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB...

  6. 40 CFR 761.359 - Reporting the PCB concentrations in samples.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Reporting the PCB concentrations in... COMMERCE, AND USE PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for...

  7. 40 CFR 761.358 - Determining the PCB concentration of samples of waste.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Determining the PCB concentration of..., DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB...

  8. 40 CFR 761.358 - Determining the PCB concentration of samples of waste.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Determining the PCB concentration of..., DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB...

  9. 40 CFR 761.359 - Reporting the PCB concentrations in samples.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Reporting the PCB concentrations in... COMMERCE, AND USE PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for...

  10. 40 CFR 761.359 - Reporting the PCB concentrations in samples.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Reporting the PCB concentrations in... COMMERCE, AND USE PROHIBITIONS Sampling Non-Liquid, Non-Metal PCB Bulk Product Waste for Purposes of Characterization for PCB Disposal in Accordance With § 761.62, and Sampling PCB Remediation Waste Destined for...

  11. Laboratory study of PCB transport from primary sources to settled dust

    EPA Science Inventory

    Transport of house dust and Arizona Test Dust on polychlorinated biphenyl (PCB)-containing panels and PCB-free panels was investigated in a 30-m3 stainless steel chamber. The PCB-containing panels were aluminum sheets coated with a PCB-spiked, oil-based primer or two-part polysul...

  12. Pesticide and PCB levels in fish from Alberta (Canada)

    SciTech Connect

    Chovelon, A.; George, L.; Gulayets, C.; Hoyano, Y.; McGuinness, E.; Moore, J.; Ramamoorthy, S.; Ramamoorthy, S.; Singer, P.; Smiley, K.

    1984-01-01

    Pesticide and PCB analyses were completed on fat and muscle samples of 750 fish collected from 11 major lakes and rivers in Alberta. Although phenoxy and organophosphate residues were always below detectable limits, traces of chlorinated pesticides and their derivatives, particularly DDE, DDD and chlordane, were detected in most fat samples. PCB levels exceeded 25 mg/kg in the fat of several species from the North Saskatchewan River but were generally lower in the other systems. Analysis of 160 sediment samples from the North Saskatchewan River revealed no point source of PCB contamination.

  13. FIELD ANALYTICAL SCREENING PROGRAM PCB METHOD: INNOVATIVE TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    This innovative technology evaluation report (ITER) presents information on the demonstration of the U.S. Environmental Protection Agency (EPA) Region 7 Superfund Field Analytical Screening Program (FASP) method for determining polychlorinated biphenyl (PCB) contamination in soil...

  14. PCB's in fish from selected waters of New York State.

    PubMed

    Spagnoli, J J; Skinner, L C

    1977-09-01

    PCB residues in fish from 41 stations throughout New York State were monitored in 1975. Nearly all fish contained PCB's in detectable amounts although the levels of contamination and specific Aroclor varied. The Hudson River contained the highest known PCB concentrations within the United States; levels often exceeded 100 ppm. Other waters and fish which were significantly contaminated include Lake Ontario salmonids and Cayuga Lake lake trout. Onondaga Lake, previously closed to fishing because of mercury contamination, also appears to have abnormally high levels of PCB's approaching in some instances the action level of the Food and Drug Administration, U.S. Department of Health, Education, and Welfare. Samples from marine waters generally have contaminant levels substantially below 5.0 ppm. PMID:414199

  15. ENANTIOMERIC RATIOS OF CHIRAL PCB ATROPISOMERS IN RADIODATED SEDIMENT CORES

    EPA Science Inventory

    Enantiomeric ratios (ERs)) of chiral polychlorinated biphenyl (PCB) atropisomers were quantified in radiodated sediment cores of Lake Hartwell SC, a reservoir heavily impacted by PCBS, to study spatial and temporal changes in chirality. A chiral analysis of cores showed accumulat...

  16. FIELD ANALYTICAL SCREENING PROGRAM: PCB METHOD - INNOVATIVE TECHNOLOGY REPORT

    EPA Science Inventory

    This innovative technology evaluation report (ITER) presents information on the demonstration of the U.S. Environmental Protection Agency (EPA) Region 7 Superfund Field Analytical Screening Program (FASP) method for determining polychlorinated biphenyl (PCB) contamination in soil...

  17. The Belgian PCB and dioxin incident of January-June 1999: exposure data and potential impact on health.

    PubMed Central

    van Larebeke, N; Hens, L; Schepens, P; Covaci, A; Baeyens, J; Everaert, K; Bernheim, J L; Vlietinck, R; De Poorter, G

    2001-01-01

    In January 1999, 500 tons of feed contaminated with approximately 50 kg of polychlorinated biphenyls (PCBs) and 1 g of dioxins were distributed to animal farms in Belgium, and to a lesser extent in the Netherlands, France, and Germany. This study was based on 20,491 samples collected in the database of the Belgian federal ministries from animal feed, cattle, pork, poultry, eggs, milk, and various fat-containing food items analyzed for their PCB and/or dioxin content. Dioxin measurements showed a clear predominance of polychlorinated dibenzofuran over polychlorinated dibenzodioxin congeners, a dioxin/PCB ratio of approximately 1:50,000 and a PCB fingerprint resembling that of an Aroclor mixture, thus confirming contamination by transformer oil rather than by other environmental sources. In this case the PCBs contribute significantly more to toxic equivalents (TEQ) than dioxins. The respective means +/- SDs and the maximum concentrations of dioxin (expressed in TEQ) and PCB observed per gram of fat in contaminated food were 170.3 +/- 487.7 pg, 2613.4 pg, 240.7 +/- 2036.9 ng, and 51059.0 ng in chicken; 1.9 +/- 0.8 pg, 4.3 pg, 34.2 +/- 30.5 ng, and 314.0 ng in milk; and 32.0 +/- 104.4 pg, 713.3 pg, 392.7 +/- 2883.5 ng, and 46000.0 ng in eggs. Assuming that as a consequence of this incident between 10 and 15 kg PCBs and from 200 to 300 mg dioxins were ingested by 10 million Belgians, the mean intake per kilogram of body weight is calculated to maximally 25,000 ng PCBs and 500 pg international TEQ dioxins. Estimates of the total number of cancers resulting from this incident range between 40 and 8,000. Neurotoxic and behavioral effects in neonates are also to be expected but cannot be quantified. Because food items differed widely (more than 50-fold) in the ratio of PCBs to dioxins, other significant sources of contamination and a high background contamination are likely to contribute substantially to the exposure of the Belgian population. PMID:11333188

  18. Effects of an environmentally relevant polychlorinated biphenyl (PCB) mixture on embryonic survival and cardiac development in the domestic chicken.

    PubMed

    Carro, Tiffany; Dean, Karen; Ottinger, Mary Ann

    2013-06-01

    A 58-congener polychlorinated biphenyl (PCB) mixture based on contaminant analysis of spotted sandpiper eggs collected along the upper Hudson River, New York, USA, in 2004 was used to study in ovo PCB effects on cardiac development in the domestic chicken. Fertile eggs were injected prior to incubation with the following doses of the PCB mixture: untreated, sham, 0, 0.03, 0.08, 0.3, 0.5, 0.7, and 2.06 µg PCBs/g egg weight (toxic equivalent quotient [TEQ] range of 0.004-0.266 ng/g). In addition, there were untreated and sham-control groups. Embryonic development was monitored throughout incubation and chicks were necropsied at hatch. Hatchability followed a dose-dependent curve with significant (p < 0.05) mortality above the 0.5 µg PCBs/g egg weight treatment compared with controls. The median lethal dose (LD50) of this PCB mixture in hatchling chicks was estimated as 0.4 µg/g egg weight (0.052 ng TEQ/g egg wt) based on the lethality curve. Cardiac arrhythmia was observed at embryonic day 14 of development in embryos treated at concentrations of 0.5 µg/g egg weight and above. Histological analysis was utilized to characterize any cardiac abnormalities. Cardiomyopathies increased across treatments in a dose-dependent manner compared with control groups. Identified abnormalities included the absence of the trabeculated layer of the ventricular wall, ventricular dilation, thinning of the ventricular walls, malformation of the septal wall, and most commonly, absence of the compact layer of the ventricular wall. Chick heart width, depth, total area, compact layer depth, septal width, chamber area, and ventricular wall dimensions did not differ across treatments. The present study supports prior reports of adverse developmental effects of PCBs on cardiovascular systems in birds. Although the eggs hatched, measured cardiomyopathies suggest potential deleterious long-term impacts on individual health and fitness. PMID:23418095

  19. A Birth Cohort Study of Maternal and Infant Serum PCB-153 and DDE Concentrations and Responses to Infant Tuberculosis Vaccination

    PubMed Central

    Jusko, Todd A.; De Roos, Anneclaire J.; Lee, Sue Y.; Thevenet-Morrison, Kelly; Schwartz, Stephen M.; Verner, Marc-André; Murinova, Lubica Palkovicova; Drobná, Beata; Kočan, Anton; Fabišiková, Anna; Čonka, Kamil; Trnovec, Tomas; Hertz-Picciotto, Irva; Lawrence, B. Paige

    2015-01-01

    Background: Reasons for the highly variable and often poor protection conferred by the Mycobacterium bovis bacille Calmette–Guérin (BCG) vaccine are multifaceted and poorly understood. Objectives: We aimed to determine whether early-life exposure to PCBs (polychlorinated biphenyls) and DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] reduces 6-month infant BCG vaccine response. Methods: Data came from families participating in a prospective birth cohort in eastern Slovakia. At birth, maternal and cord blood were collected for chemical analyses, and infants were immunized with BCG. Blood was collected from infants for chemical analyses and to determine 6-month BCG-specific immunoglobulin (Ig) G and IgA levels. Multivariable linear regression models were fit to examine chemical–BCG associations among approximately 500 mother–infant pairs, with adjustment for confounders. Results: The median 6-month infant concentration of the prevalent congener PCB-153 was 113 ng/g lipid [interquartile range (IQR): 37–248], and 388 ng/g lipid (IQR: 115–847) for DDE. Higher 6-month infant concentrations of PCB-153 and DDE were strongly associated with lower 6-month BCG-specific antibody levels. For instance, BCG-specific IgG levels were 37% lower for infants with PCB-153 concentrations at the 75th percentile compared to the 25th percentile (95% CI: –42, –32; p < 0.001). Results were similar in magnitude and precision for DDE. There was also evidence of PCB–DDE additivity, where exposure to both compounds reduced anti-BCG levels more than exposure to either compound alone. Conclusions: The associations observed in this study indicate that environmental exposures may be overlooked contributors to poorer responses to BCG vaccine. The overall association between these exposures and tuberculosis incidence is unknown. Citation: Jusko TA, De Roos AJ, Lee SY, Thevenet-Morrison K, Schwartz SM, Verner MA, Palkovicova Murinova L, Drobná B, Kočan A, Fabišiková A, Čonka K

  20. Brown Norway chromosome 1 congenic reduces symptoms of renal disease in fatty Zucker rats.

    PubMed

    Warden, Craig H; Slupsky, Carolyn; Griffey, Stephen M; Bettaieb, Ahmed; Min, Esther; Le, Anh; Fisler, Janis S; Hansen, Susan; Haj, Fawaz; Stern, Judith S

    2014-01-01

    We previously reported that a congenic rat with Brown Norway (BN) alleles on chromosome 1 reduces renal disease of 15-week old fatty Zucker rats (ZUC). Development of renal disease in fatty BN congenic and fatty ZUC rats from 9 through 28 weeks is now examined. Analysis of urine metabolites by (1)H nuclear magnetic resonance (NMR) spectroscopy revealed a significantly increased urinary loss of glucose, myo-inositol, urea, creatine, and valine in ZUC. Food intake was lower in the BN congenic rats at weeks 9-24, but they weighed significantly more at 28 weeks compared with the ZUC group. Fasting glucose was significantly higher in ZUC than congenic and adiponectin levels were significantly lower in ZUC, but there was no significant genotype effect on Insulin levels. Glucose tolerance tests exhibited no significant differences between ZUC and congenic when values were normalized to basal glucose levels. Quantitative PCR on livers revealed evidence for higher gluconeogenesis in congenics than ZUC at 9 weeks. Plasma urea nitrogen and creatinine were more than 2-fold higher in 28-week ZUC. Twelve urine protein markers of glomerular, proximal and distal tubule disease were assayed at three ages. Several proteins that indicate glomerular and proximal tubular disease increased with age in both congenic and ZUC. Epidermal growth factor (EGF) level, a marker whose levels decrease with distal tubule disease, was significantly higher in congenics. Quantitative histology of 28 week old animals revealed the most significant genotype effect was for tubular dilation and intratubular protein. The congenic donor region is protective of kidney disease, and effects on Type 2 diabetes are likely limited to fasting glucose and adiponectin. The loss of urea together with a small increase of food intake in ZUC support the hypothesis that nitrogen balance is altered in ZUC from an early age. PMID:24498189

  1. Stir-bar supported micro-solid-phase extraction for the determination of polychlorinated biphenyl congeners in serum samples.

    PubMed

    Sajid, Muhammad; Basheer, Chanbasha

    2016-07-15

    In present work, a new configuration of micro-solid phase extraction was introduced and termed as stir-bar supported micro-solid-phase extraction (SB-μ-SPE). A tiny stir-bar was packed inside the porous polypropylene membrane along with sorbent material and the edges of membrane sheet were heat sealed to secure the contents. The packing of stir-bar inside the μ-SPE device does not allow the device to stick with the wall or any corner of the sample vial during extraction, which is, however, a frequent observation in routine μ-SPE. Moreover, it enhances effective surface area of the sorbent exposed to sample solution through continuous agitation (motion and rotation). It also completely immerses the SB-μ-SPE device in the sample solution even for non-polar sorbents. Polychlorinated biphenyls (PCBs) were selected as model compounds and the method performance was evaluated in human serum samples. After extraction, samples were analyzed by gas chromatography mass spectrometry (GC-MS). The factors that affect extraction efficiency of SB-μ-SPE were optimized. Under optimum conditions, a good linearity (0.1-100ngmL(-1)) with coefficients of determinations ranging from 0.9868 to 0.9992 was obtained. Limits of detections were ranged between 0.003 and 0.047ngmL(-1). Acceptable values for inter-day (3.2-9.1%) and intra-day (3.1-7.2%) relative standard deviations were obtained. The optimized method was successfully applied to determine the concentration of PCB congeners in human serum samples. PMID:27291862

  2. Different carbon sources affect PCB accumulation by marine bivalves.

    PubMed

    Laitano, M V; Silva Barni, M F; Costa, P G; Cledón, M; Fillmann, G; Miglioranza, K S B; Panarello, H O

    2016-02-01

    Pampean creeks were evaluated in the present study as potential land-based sources of PCB marine contamination. Different carbon and nitrogen sources from such creeks were analysed as boosters of PCB bioaccumulation by the filter feeder bivalve Brachidontes rodriguezii and grazer limpet Siphonaria lessoni. Carbon of different source than marine and anthropogenic nitrogen assimilated by organisms were estimated through their C and N isotopic composition. PCB concentration in surface sediments and mollusc samples ranged from 2.68 to 6.46 ng g(-1) (wet weight) and from 1074 to 4583 ng g(-1) lipid, respectively, reflecting a punctual source of PCB contamination related to a landfill area. Thus, despite the low flow of creeks, they should not be underestimated as contamination vectors to the marine environment. On the other hand, mussels PCB bioaccumulation was related with the carbon source uptake which highlights the importance to consider this factor when studying PCB distribution in organisms of coastal systems. PMID:26606107

  3. Neurobehavioral and somatic effects of perinatal PCB exposure in rats

    SciTech Connect

    Overmann, S.R.; Kostas, J.; Wilson, L.R.; Shain, W.; Bush, B.

    1987-10-01

    Developing rats were exposed to TCBs via provision of diets containing 0.02 (no PCB added), 2.4, 26, or 269 ppm Aroclor 1254 to sperm-positive female rats from mating to weaning of their pups. Provision of the 269 ppm diet decreased the number of impregnated rats that delivered a litter and lowered pup birth weight, and most pups died within 7 days of birth. Preweaning pup growth was reduced in the 26 ppm condition and slightly reduced in the 2.5 ppm condition. The ontogeny of negative geotaxis, auditory startle, and air righting was delayed in pups from the 26 ppm condition. Pups in the 2.5 ppm condition had slightly delayed development of auditory startle. Maximal electroshock seizure tests on postweaning rats showed that perinatal PCB exposure decreased seizure severity of both the 2.5 and 26 ppm groups. PCB exposure increased pup liver weights at birth and dam and pup liver weights at weaning. Spleen and thymus weights were lower in PCB-exposed pups, while brain weights were unaffected. Analytical determination of PCB levels in brain showed greater maternal transfer of PCBs during lactation than during gestation. Elevated PCB levels were detectable in brains of perinatally exposed adult rats.

  4. Pharmacokinetics of furagin, a new nitrofurantoin congener, on human volunteers.

    PubMed

    Männistö, P; Karttunen, P

    1979-06-01

    The human pharmacokinetics of a nitrofurantoin congener furagin was studied after a single oral dose of 200 mg and during a 9-day continuous treatment with a dose of 100 mg t.i.d. The same dose of nitrofurantoin served as a reference medication. In the acute cross-over phase food greatly speeded up and atropine somewhat retarded the absorption of furagin, but the total absorption remained virtually unchanged as judged from the unchanged AUC values. The furagin concentrations in serum remain several hours above the MIC concentrations of many pathogenic bacteria. Despite the high concentrations in serum, the urine levels of furagin were generally lower than those of nitrofurantoin. The 24 hr recoveries in urine were 8--13% for furagin and about 36% for nitrofurantoin. In the prolonged trial furagin was absorbed and excreted in the same way as in the acute trial. On the 9th day the concentrations in serum and urine were higher than on the first day. The urinary concentrations of both furagin and nitrofurantoin always remained well above the MIC values of the most susceptible bacteria. Several volunteers complained of nightly cramps in their calves after taking furagin for some days, otherwise the side effects were minimal. PMID:468451

  5. Adenosine Amine Congener as a Cochlear Rescue Agent

    PubMed Central

    Vlajkovic, Srdjan M.; Chang, Hao; Paek, Song Yee; Chi, Howard H.-T.; Sreebhavan, Sreevalsan; Telang, Ravindra S.; Tingle, Malcolm; Housley, Gary D.; Thorne, Peter R.

    2014-01-01

    We have previously shown that adenosine amine congener (ADAC), a selective A1 adenosine receptor agonist, can ameliorate noise- and cisplatin-induced cochlear injury. Here we demonstrate the dose-dependent rescue effects of ADAC on noise-induced cochlear injury in a rat model and establish the time window for treatment. Methods. ADAC (25–300 μg/kg) was administered intraperitoneally to Wistar rats (8–10 weeks old) at intervals (6–72 hours) after exposure to traumatic noise (8–16 kHz, 110 dB sound pressure level, 2 hours). Hearing sensitivity was assessed using auditory brainstem responses (ABR) before and 12 days after noise exposure. Pharmacokinetic studies investigated ADAC concentrations in plasma after systemic (intravenous) administration. Results. ADAC was most effective in the first 24 hours after noise exposure at doses >50 μg/kg, providing up to 21 dB protection (averaged across 8–28 kHz). Pharmacokinetic studies demonstrated a short (5 min) half-life of ADAC in plasma after intravenous administration without detection of degradation products. Conclusion. Our data show that ADAC mitigates noise-induced hearing loss in a dose- and time-dependent manner, but further studies are required to establish its translation as a clinical otological treatment. PMID:25243188

  6. The greening of PCB analytical methods

    SciTech Connect

    Erickson, M.D.; Alvarado, J.S.; Aldstadt, J.H.

    1995-12-01

    Green chemistry incorporates waste minimization, pollution prevention and solvent substitution. The primary focus of green chemistry over the past decade has been within the chemical industry; adoption by routine environmental laboratories has been slow because regulatory standard methods must be followed. A related paradigm, microscale chemistry has gained acceptance in undergraduate teaching laboratories, but has not been broadly applied to routine environmental analytical chemistry. We are developing green and microscale techniques for routine polychlorinated biphenyl (PCB) analyses as an example of the overall potential within the environmental analytical community. Initial work has focused on adaptation of commonly used routine EPA methods for soils and oils. Results of our method development and validation demonstrate that: (1) Solvent substitution can achieve comparable results and eliminate environmentally less-desirable solvents, (2) Microscale extractions can cut the scale of the analysis by at least a factor of ten, (3) We can better match the amount of sample used with the amount needed for the GC determination step, (4) The volume of waste generated can be cut by at least a factor of ten, and (5) Costs are reduced significantly in apparatus, reagent consumption, and labor.

  7. Congener Profiles and Source-Wise Phase Partitioning Analysis of PCDDs/Fs and PCBs in Gyeonggi-Do Ambient Air, South Korea

    PubMed Central

    Heo, Jongwon; Kim, Donggi; Lee, Gangwoong

    2014-01-01

    The atmospheric concentrations and gas–particle partitioning of polychlorinated dibenzo-p-dioxins and furans (PCDDs/Fs) and polychlorinated biphenyls (PCBs) were investigated at two sites (Suwon and Ansan) in Gyeonggi-do, a heavily industrialized area of Korea, during the year 2010. The sum level (Σ17) of PCDDs/Fs and dioxin-like PCBs (dl-PCBs) in the ambient air at Suwon and Ansan ranged from 0.04 to 0.30 pg-TEQ·m−3 (geometric mean: 0.09 pg-TEQ·m−3) and 0.17 to 0.63 pg-TEQ·m−3 (geometric mean: 0.36 pg-TEQ·m−3), respectively. Moreover, the geometric mean concentrations of Σ180 PCBs at Suwon and Ansan were 233.6 pg·m−3 and 274.2 pg·m−3, respectively, and di-chlorinated biphenyls and tri-chlorinated biphenyls were the predominant homologs. Among the PCB congeners, 3,3'-dichlorobiphenyl (PCB-11) was the dominant species at both sites during all sampling periods, comprising up to 15.1% of Σ180 PCBs at Ansan and 24.6% at Suwon. We evaluated their gas-to-particle equilibriums by conducting regression between the particle–gas partition coefficient Kp (m3·ug−1) and the corresponding subcooled liquid vapor pressure (PL°). The slope (m) values for log–log plots of Kp vs. PL° were steeper in industrial areas owing to local source proximity. Moreover, owing to enhanced emissions from combustion-related sources at low temperatures, PCDD/Fs exhibited the largest deviation from the regression line of the particle–gas partition coefficient. Incinerators were found to be the primary emission source of atmospheric PCDDs/Fs, whereas re-evaporation from pre-existing environmental loads (e.g., storage areas or spilled soil and water bodies) was the dominant source for PCBs. PMID:25347194

  8. Bioaccumulation of dioxin-like substances and selected brominated flame retardant congeners in the fat and livers of black pigs farmed within the Nebrodi Regional Park of Sicily.

    PubMed

    Brambilla, Gianfranco; De Filippis, Stefania Paola; Iamiceli, Anna Laura; Iacovella, Nicola; Abate, Vittorio; Aronica, Vincenzo; Di Marco, Vincenzo; di Domenico, Alessandro

    2011-02-01

    An observational study was designed to assess the bioaccumulation of polychlorodibenzodioxins (PCDD) and polychlorodibenzofurans (PCDF), dioxin-like polychlorobiphenyls (DL-PCB), and 13 selected polybromodiphenylethers (PBDE) in autochthonous pigs reared in the Nebrodi Park of Sicily (Italy). Perirenal fat and liver samples were drawn from animals representative of three different outdoor farming systems and from wild pigs and then analyzed for the chemicals mentioned previously. The highest concentrations of PCDD + PCDF and DL-PCB were detected in the fat (0.45 and 0.35 pg World Health Organization toxicity equivalents [WHO-TE] per g of fat base [FB], respectively) and livers (12.7 and 3.28 pg WHO-TE per g FB) of the wild group, whereas the free-ranging group showed the lowest levels (0.05 and 0.03 pg WHO-TE per g FB in fat and 0.78 and 0.27 pg WHO-TE per g FB in livers). The sum of PBDE congeners was highest in wild pigs (0.52 ng/g FB in fat and 5.64 ng/g FB in livers) and lowest in the farmed group (0.14 ng/g FB in fat and 0.28 ng/g FB in livers). The contamination levels in fat and livers of outdoor pigs had mean concentration values lower than those levels reported for intensively indoor-farmed animals. In wild pigs, bioaccumulation was associated with their free grazing in areas characterized by bush fires. The results of this study aid to emphasize the quality of the environment as a factor to guarantee food safety in typical processed pig meat products, specifically from outdoor and extensive Nebrodi farming systems. PMID:21333146

  9. The Identification of Congeners and Aliens by Drosophila Larvae

    PubMed Central

    Del Pino, Francisco; Jara, Claudia; Pino, Luis; Medina-Muñoz, María Cristina; Alvarez, Eduardo; Godoy-Herrera, Raúl

    2015-01-01

    We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b) mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b), Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles. PMID:26313007

  10. Use of herbarium data to evaluate weediness in five congeners

    PubMed Central

    Hanan-A., Ana M.; Vibrans, Heike; Cacho, N. Ivalú; Villaseñor, José L.; Ortiz, Enrique; Gómez-G., Vinicio A.

    2016-01-01

    It is often desirable to quantify a plant's relative weediness or synanthropy, that is, the degree to which a species associates with human-caused disturbance, in order to study and understand the biology, ecology and evolution of weeds and invasive plants. Herbarium specimens are among the most accessible and verifiable sources of data on distribution and habitat. However, the habitat distribution of species may not be reflected accurately by herbarium specimen data, due to well-known biases in plant collection. Here, we assess how well herbarium specimens reflect species' weediness, when compared with direct field surveys. We used five species of Melampodium (Asteraceae) and classified their degree of weediness with a modification of Nuorteva's synanthropy index, based on herbarium specimens. We then modelled the distribution of our focal species in Mexico using MaxEnt and identified a polygon of ∼3000 km2 in the state of Nayarit, Mexico, where there was a high probability of finding all five species. Systematic field searches in the target area documented all visible populations of four species along major and minor roads. Then we, again, classified their degree of weediness with the synanthropy index, based now on field data, and compared. We found that herbarium data were an accurate predictor of a species' weediness relative to its congeners despite the well-documented skew of herbarium data towards natural areas, which our data reflected as well. So, herbarium data can be used to classify species' weediness relative to each other, but not in absolute terms, if the specimens were correctly identified and none of the species were subject to particular collection bias. This study is the first attempt to compare herbarium and field data on this subject and may be relevant for other types of investigations based on herbarium data. Our work also highlights the usefulness of distribution models based on herbarium specimens. PMID:26672076

  11. The Identification of Congeners and Aliens by Drosophila Larvae.

    PubMed

    Del Pino, Francisco; Jara, Claudia; Pino, Luis; Medina-Muñoz, María Cristina; Alvarez, Eduardo; Godoy-Herrera, Raúl

    2015-01-01

    We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b) mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b), Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles. PMID:26313007

  12. Organic anion transporting polypeptides in the hepatic uptake of PBDE congeners in mice

    SciTech Connect

    Pacyniak, Erik; Hagenbuch, Bruno; The University of Kansas Cancer Center, Kansas City, KS ; Klaassen, Curtis D.; Lehman-McKeeman, Lois; Guo, Grace L.

    2011-11-15

    BDE47, BDE99 and BDE153 are the predominant polybrominated diphenyl ether (PBDE) congeners detected in humans and can induce drug metabolizing enzymes in the liver. We have previously demonstrated that several human liver organic anion transporting polypeptides (humans: OATPs; rodents: Oatps) can transport PBDE congeners. Mice are commonly used to study the toxicity of chemicals like the PBDE congeners. However, the mechanism of the hepatic PBDE uptake in mice is not known. Therefore, the purpose of the current study was to test the hypothesis that BDE47, BDE99, and BDE153 are substrates of mouse hepatic Oatps (Oatp1a1, Oatp1a4, Oatp1b2, and Oatp2b1). We used Human Embryonic Kidney 293 (HEK293) cells transiently expressing individual Oatps and quantified the uptake of BDE47, BDE99, and BDE153. Oatp1a4, Oatp1b2, and Oatp2b1 transported all three PBDE congeners, whereas Oatp1a1 did transport none. Kinetic studies demonstrated that Oatp1a4 and Oatp1b2 transported BDE47 with the greatest affinity, followed by BDE99 and BDE153. In contrast, Oatp2b1 transported all three PBDE congeners with similar affinities. The importance of hepatic Oatps for the liver accumulation of BDE47 was confirmed using Oatp1a4-, and Oatp1b2-null mice. -- Highlights: Black-Right-Pointing-Pointer PBDE congeners are substrates of OATPs expressed in human hepatocytes. Black-Right-Pointing-Pointer Mice are commonly used to study the toxicity of chemicals like the PBDE congeners. Black-Right-Pointing-Pointer Oatp1a4, Oatp1b2, and Oatp2b1 transported all three PBDE congeners in vitro. Black-Right-Pointing-Pointer In vivo Oatp1a4 plays a minor and Oatp1b2 a major role in BDE47 liver accumulation.

  13. Assessing human polychlorinated biphenyl contamination for epidemiologic studies: lessons from patterns of congener concentrations in Canadians in 1992.

    PubMed Central

    Gladen, Beth C; Doucet, Josée; Hansen, Larry G

    2003-01-01

    Humans are always exposed to mixtures of polychlorinated biphenyls (PCBs), so assessment of their health effects is complicated. Because the original sources are relatively standard mixtures that change in predictable ways while traversing the environment, there is substantial uniformity in the congener mixtures people carry. To the extent that concentrations are highly correlated, measuring multiple congeners within correlated groups would be unnecessary and estimation of separate biologic effects would be impossible. We examined correlation patterns in previously collected data on 38 congeners (and 14 other organochlorines) from 497 human milk samples from Canada from 1992. Congeners 138, 153, 156, 157, 170, 183, 187, 194, 199, and 203 were highly intercorrelated; 180 had slightly lower correlations with this group. Congeners 74, 105, and 118 were highly intercorrelated and moderately to highly correlated with the first group. Congener 99 had moderate correlations with both these groups, and congener 66 had lesser correlations with the primary group. In contrast, congeners 28, 44, 49, 60, 90/101, 128, 137, and 193 showed little correlation with any other congeners. The remaining 14 congeners were uninformative; they were quantified in fewer than 30% of samples, and varying lipid concentrations meant that those quantified were not necessarily at higher concentrations than those not quantified. In study of human health effects of PCBs, the congener pattern present in the population under study should be examined when deciding which congeners to measure; instead of solely redundant or uninformative congeners, attention should be given to other congeners that may be more useful in addressing the question of interest. PMID:12676596

  14. Trait responses of invasive aquatic macrophyte congeners: colonizing diploid outperforms polyploid

    PubMed Central

    Grewell, Brenda J.; Skaer Thomason, Meghan J.; Futrell, Caryn J.; Iannucci, Maria; Drenovsky, Rebecca E.

    2016-01-01

    Understanding traits underlying colonization and niche breadth of invasive plants is key to developing sustainable management solutions to curtail invasions at the establishment phase, when efforts are often most effective. The aim of this study was to evaluate how two invasive congeners differing in ploidy respond to high and lowresource availability following establishment from asexual fragments. Because polyploids are expected to have wider niche breadths than diploid ancestors, we predicted that a decaploid species would have superior ability to maximize resource uptake and use, and outperform a diploid congener when colonizing environments with contrasting light and nutrient availability. A mesocosm experiment was designed to test the main and interactive effects of ploidy (diploid and decaploid) and soil nutrient availability (low and high) nested within light environments (shade and sun) of two invasive aquatic plant congeners. Counter to our predictions, the diploid congener outperformed the decaploid in the early stage of growth. Although growth was similar and low in the cytotypes at low nutrient availability, the diploid species had much higher growth rate and biomass accumulation than the polyploid with nutrient enrichment, irrespective of light environment. Our results also revealed extreme differences in time to anthesis between the cytotypes. The rapid growth and earlier flowering of the diploid congener relative to the decaploid congener represent alternate strategies for establishment and success. PMID:26921139

  15. Functionalized Congener Approach to the Design of Ligands for G Protein–Coupled Receptors (GPCRs)

    PubMed Central

    Jacobson, Kenneth A.

    2009-01-01

    Functionalized congeners, in which a chemically functionalized chain is incorporated at an insensitive site on a pharmacophore, have been designed from the agonist and antagonist ligands of various G protein–coupled receptors (GPCRs). These chain extensions enable a conjugation strategy for detecting and characterizing GPCR structure and function and pharmacological modulation. The focus in many studies of functionalized congeners has been on two families of GPCRs: those responding to extracellular purines and pyrimidines—i.e., adenosine receptors (ARs) and P2Y nucleotide receptors. Functionalized congeners of small-molecule as ligands for other GPCRs and non-G protein coupled receptors have also been designed. For example, among biogenic amine neurotransmitter receptors, muscarinic acetylcholine receptor antagonists and adrenergic receptor ligands have been studied with a functionalized congener approach. Adenosine A1, A2A, and A3 receptor functionalized congeners have yielded macromolecular conjugates, irreversibly binding AR ligands for receptor inactivation and crosslinking, radioactive probes that use prosthetic groups, immobilized ligands for affinity chromatography, and dual-acting ligands that function as binary drugs. Poly(amidoamine) dendrimers have served as nanocarriers for covalently conjugated AR functionalized congeners. Rational methods of ligand design derived from molecular modeling and templates have been included in these studies. Thus, the design of novel ligands, both small molecules and macromolecular conjugates, for studying the chemical and biological properties of GPCRs have been developed with this approach, has provided researchers with a strategy that is more versatile than the classical medicinal chemical approaches. PMID:19405524

  16. Residual congener pattern of dioxins in human breast milk in southern Vietnam.

    PubMed

    Tawara, Kenji; Nishijo, Muneko; Maruzeni, Shoko; Nakagawa, Hideaki; Kido, Teruhiko; Naganuma, Rie; Suzuki, Hiroyuki; Nhu, Dang Duc; Hung, Nguyen Ngoc; Thom, Le Thi Hong

    2011-08-01

    This study evaluated residual congener patterns of dioxin/furan (=PCDD/DF) related to tactical herbicides aerially sprayed over the regions of southern Vietnam through Operation Ranch Hand. The study focused on Cam Chinh (CC) commune, Quang Tri province (an area sprayed with tactical herbicides), and the Cam Phuc (CP) commune, Ha Tinh province (a non-sprayed area). Breast milk samples for analysis were collected in September 2002 and July 2003 from lactating primiparous and multiparous mothers born after the war (<31 years old). We found the levels of each congener in the CC commune were higher than in the CP commune, and determined specificity in the PCDD/DF congener pattern in CC commune samples by cluster analysis. The congener pattern is characterized by higher (the hexa-, the hepta-, and the octa-) chlorinated PCDD/DFs; this appears to be the same profile as that presented by pentachlorophenol (PCP), rather than 2,4,5-trichlorophenoxy acid (2,4,5-T) contaminated with 2,3,7,8-TCDD. A GC/MS study in the 1970s detected the chlorophenols 2,4-di and 2,4,6-trichlorophenol in some Agent Orange samples, which contained, like PCP, a wide variety of PCDD/DF congeners. In this context, it may be expected that certain tactical herbicides contaminated with various chlorophenol impurities, have a unique congener pattern when compared with pure 2,4,5-T formulations. PMID:21680010

  17. Trait responses of invasive aquatic macrophyte congeners: colonizing diploid outperforms polyploid.

    PubMed

    Grewell, Brenda J; Skaer Thomason, Meghan J; Futrell, Caryn J; Iannucci, Maria; Drenovsky, Rebecca E

    2016-01-01

    Understanding traits underlying colonization and niche breadth of invasive plants is key to developing sustainable management solutions to curtail invasions at the establishment phase, when efforts are often most effective. The aim of this study was to evaluate how two invasive congeners differing in ploidy respond to high and lowresource availability following establishment from asexual fragments. Because polyploids are expected to have wider niche breadths than diploid ancestors, we predicted that a decaploid species would have superior ability to maximize resource uptake and use, and outperform a diploid congener when colonizing environments with contrasting light and nutrient availability. A mesocosm experiment was designed to test the main and interactive effects of ploidy (diploid and decaploid) and soil nutrient availability (low and high) nested within light environments (shade and sun) of two invasive aquatic plant congeners. Counter to our predictions, the diploid congener outperformed the decaploid in the early stage of growth. Although growth was similar and low in the cytotypes at low nutrient availability, the diploid species had much higher growth rate and biomass accumulation than the polyploid with nutrient enrichment, irrespective of light environment. Our results also revealed extreme differences in time to anthesis between the cytotypes. The rapid growth and earlier flowering of the diploid congener relative to the decaploid congener represent alternate strategies for establishment and success. PMID:26921139

  18. Developmental exposure to polychlorinated biphenyls PCB153 or PCB126 impairs learning ability in young but not in adult rats.

    PubMed

    Piedrafita, Blanca; Erceg, Slaven; Cauli, Omar; Monfort, Pilar; Felipo, Vicente

    2008-01-01

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants present in the food chain and in human blood and milk. Exposure to PCBs during pregnancy and lactation leads to cognitive impairment in children. The underlying mechanisms remain unclear. Some PCBs are endocrine disrupters. The aim of this work was to assess whether exposure of rats to PCB126 (dioxin-like) or PCB153 (non-dioxin-like) during pregnancy and lactation affects the ability of the pups to learn a Y maze conditional discrimination task and/or the function of the glutamate-nitric oxide (NO)-cGMP pathway in brain in vivo when the rats are young (3 months) or adult (7-8 months). After finishing the learning experiments, the function of the pathway was analysed in the same rats by in vivo brain microdialysis. The results obtained show that perinatal exposure to PCB153 or PCB126: (1) impairs learning ability in young but not in adult rats, (2) impairs the glutamate-NO-cGMP pathway function in cerebellum in vivo in young but not in adult rats and (3) affect these parameters in males and females similarly. PCB126 is around 10 000-fold more potent than PCB153. In control rats the function of the glutamate-NO-cGMP pathway and learning ability are lower in adult than in young rats. These age-related differences are not present in rats exposed to PCBs. The impairment of the glutamate-NO-cGMP pathway function induced at young age by developmental exposure to the PCBs could be one of the mechanisms contributing to the cognitive impairment found in children whose mothers ingested PCB-contaminated food during pregnancy and lactation. PMID:18093177

  19. Dioxin, dibenzofuran, and polychlorinated biphenyl (PCB) levels in food from Agent Orange-sprayed and nonsprayed areas of Laos.

    PubMed

    Schecter, Arnold; Pavuk, Marian; Malisch, Rainer; Ryan, John Jake

    2003-11-28

    During the Vietnam War, a phenoxy-herbicide mixture called Agent Orange, which was contaminated with 2,3,7,8-tetrachlorodibenzodioxin, or TCDD, was used primarily for destruction of forest and other foliage in order to prevent enemy troop movement and protect American and allied troops and military bases in the south of Vietnam. Smaller areas of Laos and Cambodia were also sprayed with Agent Orange between 1962 and 1971 from fixed-wing aircraft. In 2001, 28 food samples consisting of meat, fish, and dairy products were collected in sprayed and nonsprayed areas of Laos and analyzed for dioxins, dioxinlike dibenzofurans, and selected polychlorinated biphenyl (PCB) congeners by high-resolution gas chromatography/high-resolution mass spectrometry at laboratories in Germany and Canada. Low levels of dioxin and other dioxinlike substances were found in Laotian food, similar to levels present in recent exported Vietnamese food to United States. Vietnam is geographically adjacent to Laos. Total dioxin toxic equivalent (TEQ) levels were similar in samples from sprayed and non-sprayed areas, ranging from 0.009 to 0.851 pg/g or parts per trillion (ppt) in sprayed Sepone, and from 0.022 to 0.537 pg/g or ppt wet weight in non sprayed Vientiane. However, the Laotian fish samples from the Agent Orange-sprayed area had, on average, a higher proportion of total TEQ from TCDD (31.7% vs. 9.4%) compared to the nonsprayed area. Some other food items, duck eggs and pork liver from Sepone, also had severalfold higher TCDD levels than similar food samples from Vientiane, 0.029 vs. 0.011 pg/g and 0.070 vs. 0.004 pg/g wet weight, respectively. There were no substantial differences in levels of dibenzofuran and PCB congeners. In general, elevated TCDD levels were not found in Laotian food samples. It is possible that dioxin-contaminated areas, or "hot spots," exist in Laos as they do in Vietnam, although they have not yet been identified. PMID:14710598

  20. Assimilation of selected PAH and PCB congeners sorbed to sediment by benthic invertebrates. Annual report, 15 Oct 90-14 Oct 91

    SciTech Connect

    Lydy, M.J.

    1991-08-29

    Methods have been developed for removing and manipulating fecal pellets, and techniques for measuring organic carbon in sediment and fecal pellets and lipid content in Diporeia have been learned. A simple and time efficient extraction procedure has been developed to extract 14C-B(a)P and 51Cr from sediment, Diporeia and fecal pellets. In addition, experiments have shown that 51Cr can be used as a conservative tracer for Diporeia and sediment. Good progress has been made in developing the basic methods involved in determining assimilation efficiencies and preliminary data have been collected for the direct measurement and dual-labeled approaches independent of one another.

  1. Survey of persistent organochlorine contaminants (PCDD, PCDF, and PCB) in fish collected from the Polish Baltic fishing areas.

    PubMed

    Piskorska-Pliszczynska, Jadwiga; Maszewski, Sebastian; Warenik-Bany, Malgorzata; Mikolajczyk, Szczepan; Goraj, Lukasz

    2012-01-01

    Concentrations and congener-specific profiles of PCDDs, PCDFs, dl-PCBs, and ndl-PCBs were determined in five species of edible fish from the Baltic Sea (ICES 24-27): salmon (Salmo salar), Baltic herring (Clupea harengus membras), sprat (Sprattus sprattus balticus), sea trout (Salmo trutta m.trutta), and cod (Gadus morhua callarias). Marker PCBs were the dominant compounds (0.07-60.84 ng/g w.w.), followed by dl-PCBs (0.64-6.07 pg WHO-TEQ/g w.w.) and PCDD/PCDFs (0.22-5.67 pg WHO-TEQ w.w). The concentration levels of contaminants varied between species. Salmon possessed the highest concentrations (up to 14.11 ± 2.36 pg WHO-TEQ/g w.w.) and cod the lowest ones (0.84 ± 0.14 pg WHO-TEQ/g w.w.). Congener profile in the fish tested had similar pattern. The largest contribution to the dioxin toxicity was caused successively by PCB 126, 118, 156, furans (2,3,4,7,8-PeCDF and 2,3,7,8-TCDF), and two dioxins: 1,2,3,7,8-PeCDD and 2,3,7,8-TCDD. Although the dietary consumption of fish from southwest region of the Baltic Sea did not represent a risk for human health (because of very low consumption of marine fish), the excessive eating of some of them may be of significance importance for health of various subgroups of consumers (fishermen). PMID:22593715

  2. Survey of Persistent Organochlorine Contaminants (PCDD, PCDF, and PCB) in Fish Collected from the Polish Baltic Fishing Areas

    PubMed Central

    Piskorska-Pliszczynska, Jadwiga; Maszewski, Sebastian; Warenik-Bany, Malgorzata; Mikolajczyk, Szczepan; Goraj, Lukasz

    2012-01-01

    Concentrations and congener-specific profiles of PCDDs, PCDFs, dl-PCBs, and ndl-PCBs were determined in five species of edible fish from the Baltic Sea (ICES 24–27): salmon (Salmo salar), Baltic herring (Clupea harengus membras), sprat (Sprattus sprattus balticus), sea trout (Salmo trutta m.trutta), and cod (Gadus morhua callarias). Marker PCBs were the dominant compounds (0.07–60.84 ng/g  w.w.), followed by dl-PCBs (0.64–6.07 pg WHO-TEQ/g w.w.) and PCDD/PCDFs (0.22–5.67 pg WHO-TEQ w.w). The concentration levels of contaminants varied between species. Salmon possessed the highest concentrations (up to 14.11 ± 2.36 pg WHO-TEQ/g  w.w.) and cod the lowest ones (0.84 ± 0.14 pg WHO-TEQ/g  w.w.). Congener profile in the fish tested had similar pattern. The largest contribution to the dioxin toxicity was caused successively by PCB 126, 118, 156, furans (2,3,4,7,8-PeCDF and 2,3,7,8-TCDF), and two dioxins: 1,2,3,7,8-PeCDD and 2,3,7,8-TCDD. Although the dietary consumption of fish from southwest region of the Baltic Sea did not represent a risk for human health (because of very low consumption of marine fish), the excessive eating of some of them may be of significance importance for health of various subgroups of consumers (fishermen). PMID:22593715

  3. Remediation of PCB contaminated soils using iron nano-particles.

    PubMed

    Varanasi, Patanjali; Fullana, Andres; Sidhu, Sukh

    2007-01-01

    In this study, iron nano-particles were used to remediate PCB contaminated soil and an attempt was made to maximize PCB destruction in each treatment step. The results show that nano-particles do aid in the dechlorination process and high PCB destruction efficiencies can be achieved. The destruction efficiency during the preliminary treatment (mixing of soil and iron nano-particles in water) can be increased by increasing the water temperature. The maximum thermal destruction (pyrolysis/combustion of soil after preliminary treatment) of soil-bound PCBs occurs at 300 degrees C in air. A minimum total PCB destruction efficiency of 95% can be achieved by this process. The effect of changing treatment parameters such as type of mixing, time of mixing and mixing conditions and application of other catalysts like iron oxide and V(2)O(5)/TiO(2) was also investigated. It was found that at 300 degrees C in air, iron oxide and V(2)O(5)/TiO(2) are also good catalysts for remediating PCB contaminated soils. PMID:16962632

  4. Lack of data drives uncertainty in PCB health risk assessments.

    PubMed

    Cogliano, Vincent James

    2016-02-01

    Health risk assessments generally involve many extrapolations: for example, from animals to humans or from high doses to lower doses. Health risk assessments for PCBs involve all the usual uncertainties, plus additional uncertainties due to the nature of PCBs as a dynamic, complex mixture. Environmental processes alter PCB mixtures after release into the environment, so that people are exposed to mixtures that might not resemble the mixtures where there are toxicity data. This paper discusses the evolution of understanding in assessments of the cancer and noncancer effects of PCBs. It identifies where a lack of data in the past contributed to significant uncertainty and where new data subsequently altered the prevailing understanding of the toxicity of PCB mixtures, either qualitatively or quantitatively. Finally, the paper identifies some uncertainties remaining for current PCB health assessments, particularly those that result from a lack of data on exposure through nursing or on effects from inhalation of PCBs. PMID:26347413

  5. Temporal trends toward stability of Hudson River PCB contamination

    SciTech Connect

    Sloan, R.J.; Simpson, K.W.; Schroeder, R.A.; Barnes, C.R.

    1983-10-01

    PCB was used in the manufacture of electrical equipment at two General Electric Company (GE) facilities located on the upper Hudson River about 1 km apart in Fort Edward and Hudson Falls (Washington Co.) New York. Discharges of PCB from these plants resulted in concentrations in bottom sediments of the Hudson River which now exceed those of other major rivers by about two orders of magnitude and those of small remote streams by more than three orders of magnitude. Intensive monitoring was initiated in 1977 by the New York State Department of Environmental Conservation (DEC) to ascertain the magnitude of and trends in contaminant conditions of biotic and physical strata. The paper summarizes PCB trends from 1977 to 1981 in three major monitoring components - water, multiplate residues and fish.

  6. PCB Drill Path Optimization by Combinatorial Cuckoo Search Algorithm

    PubMed Central

    Lim, Wei Chen Esmonde; Kanagaraj, G.; Ponnambalam, S. G.

    2014-01-01

    Optimization of drill path can lead to significant reduction in machining time which directly improves productivity of manufacturing systems. In a batch production of a large number of items to be drilled such as printed circuit boards (PCB), the travel time of the drilling device is a significant portion of the overall manufacturing process. To increase PCB manufacturing productivity and to reduce production costs, a good option is to minimize the drill path route using an optimization algorithm. This paper reports a combinatorial cuckoo search algorithm for solving drill path optimization problem. The performance of the proposed algorithm is tested and verified with three case studies from the literature. The computational experience conducted in this research indicates that the proposed algorithm is capable of efficiently finding the optimal path for PCB holes drilling process. PMID:24707198

  7. PCB drill path optimization by combinatorial cuckoo search algorithm.

    PubMed

    Lim, Wei Chen Esmonde; Kanagaraj, G; Ponnambalam, S G

    2014-01-01

    Optimization of drill path can lead to significant reduction in machining time which directly improves productivity of manufacturing systems. In a batch production of a large number of items to be drilled such as printed circuit boards (PCB), the travel time of the drilling device is a significant portion of the overall manufacturing process. To increase PCB manufacturing productivity and to reduce production costs, a good option is to minimize the drill path route using an optimization algorithm. This paper reports a combinatorial cuckoo search algorithm for solving drill path optimization problem. The performance of the proposed algorithm is tested and verified with three case studies from the literature. The computational experience conducted in this research indicates that the proposed algorithm is capable of efficiently finding the optimal path for PCB holes drilling process. PMID:24707198

  8. Single and multiple congenic strains for hydrocephalus in the H-Tx rat

    PubMed Central

    Jones, Hazel C.; Chen, Gin-Fu; Yehia, Baligh R.; Carter, Barbara J.; Akins, Elizabeth J.; Wolpin, Logan C.

    2010-01-01

    The H-Tx rat has fetal-onset hydrocephalus with a complex mode of inheritance. Previously, quantitative trait locus mapping using a backcross with Fischer F344 rats demonstrated genetic loci significantly linked to hydrocephalus on Chromosomes 10, 11, and 17. Hydrocephalus was preferentially associated with heterozygous alleles on Chrs 10 and 11 and with homozygous alleles on Chr 17. This study aimed to determine the phenotypic contribution of each locus by constructing single and multiple congenic strains. Single congenic rats were constructed using Fischer F344 as the recipient strain and a marker-assisted protocol. The homozygous strains were maintained for eight generations and the brains examined for dilated ventricles indicative for hydrocephalus. No congenic rats had severe (overt) hydrocephalus. A few pups and a significant number of adults had mild disease. The incidence was significantly higher in the C10 and C17 congenic strains than in the nonhydrocephalic F344 strain. Breeding to F344 to make F.H-Tx C10 or C11 rats heterozygous for the hydrocephalus locus failed to produce progeny with severe disease. Both bicongenic and tricongenic rats of different genotype combinations were constructed by crossing congenic rats. None had severe disease but the frequency of mild hydrocephalus in adults was similar to congenic rats and significantly higher than in the F344 strain. Rats with severe hydrocephalus were recovered in low numbers when single congenic or bicongenic rats were crossed with the parental H-Tx strain. It is concluded that the genetic and epigenetic factors contributing to severe hydrocephalus in the H-Tx strain are more complex than originally anticipated. PMID:15965786

  9. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: IMMUNOASSAY KIT, ENVIROLOGIX, INC., PCB IN SOIL TUBE ASSAY

    EPA Science Inventory

    In July 1997, the U.S. Environmental Protection Agency (EPA) conducted a demonstration of polychlorinated biphenyl (PCB) field analytical techniques. The purpose of this demonstration was to evaluate field analytical technologies capable of detecting and quantifying PCB's in soi...

  10. Estimating Time-Varying PCB Exposures Using Person-Specific Predictions to Supplement Measured Values: A Comparison of Observed and Predicted Values in Two Cohorts of Norwegian Women

    PubMed Central

    Nøst, Therese Haugdahl; Breivik, Knut; Wania, Frank; Rylander, Charlotta; Odland, Jon Øyvind; Sandanger, Torkjel Manning

    2015-01-01

    Background Studies on the health effects of polychlorinated biphenyls (PCBs) call for an understanding of past and present human exposure. Time-resolved mechanistic models may supplement information on concentrations in individuals obtained from measurements and/or statistical approaches if they can be shown to reproduce empirical data. Objectives Here, we evaluated the capability of one such mechanistic model to reproduce measured PCB concentrations in individual Norwegian women. We also assessed individual life-course concentrations. Methods Concentrations of four PCB congeners in pregnant (n = 310, sampled in 2007–2009) and postmenopausal (n = 244, 2005) women were compared with person-specific predictions obtained using CoZMoMAN, an emission-based environmental fate and human food-chain bioaccumulation model. Person-specific predictions were also made using statistical regression models including dietary and lifestyle variables and concentrations. Results CoZMoMAN accurately reproduced medians and ranges of measured concentrations in the two study groups. Furthermore, rank correlations between measurements and predictions from both CoZMoMAN and regression analyses were strong (Spearman’s r > 0.67). Precision in quartile assignments from predictions was strong overall as evaluated by weighted Cohen’s kappa (> 0.6). Simulations indicated large inter-individual differences in concentrations experienced in the past. Conclusions The mechanistic model reproduced all measurements of PCB concentrations within a factor of 10, and subject ranking and quartile assignments were overall largely consistent, although they were weak within each study group. Contamination histories for individuals predicted by CoZMoMAN revealed variation between study subjects, particularly in the timing of peak concentrations. Mechanistic models can provide individual PCB exposure metrics that could serve as valuable supplements to measurements. Citation Nøst TH, Breivik K, Wania F

  11. Comparison of PCDD/F and dl-PCB levels in Turkish foodstuffs: industrial versus rural, local versus supermarket products, and assessment of dietary intake.

    PubMed

    Kilic, Devrim; Çakıroğulları, Gül Çelik; Uçar, Yunus; Theelen, Rob; Traag, Wim

    2011-01-01

    Polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) and dioxin-like and non-dioxin-like (indicator) polychlorinated biphenyls (PCBs) were monitored in various foodstuffs of animal origin and edible oil samples obtained from two different cities in Turkey both rural and industrial. Total dioxin+dioxin-like PCBs and indicator PCB concentrations of pooled samples ranged 0.20-4.19 pg World Health Organization-Toxic Equivalency (WHO-TEQ)(1998)/g fat and 57.2-1710 pg/g fat, respectively. The dominant congeners were 2,3,4,7,8-PeCDF, 1,2,3,7,8-PeCDD, 2,3,7,8-TCDD and PCB126. Dietary intake of dioxin+dioxin-like PCBs and indicator PCBs from fish, dairy products, edible oil, egg and meat was 0.509 pg WHO-TEQ1998/kg bw (body weight)/day and 839 pg/kg bw/day in Afyon and 0.588 pg WHO-TEQ1998/ kg bw/day and 1070 pg/kg bw/day in Kocaeli, respectively. The major contributors to total exposure were dairy products and fish. Despite the unexplained high contamination level in an individual egg sample from Kocaeli, average concentration levels in Turkey, even in industrialized regions, were low compared to reported concentrations in Western Europe. Exposure levels were well below the tolerable daily intake (TDI) of 2 pg WHO-TEQ1998/kg body weight. PMID:21547797

  12. Study on the plasma treatment of waste oil containing PCB

    NASA Astrophysics Data System (ADS)

    Park, H. S.; Lukashov, V. P.; Vashchenko, S. P.; Morozov, S. V.

    2009-12-01

    The paper presents the results of treatment of transformer oil containing less than 2 ppm polychlorinated biphenyls (PCB) in a plant of high-temperature plasma melting of ash residues after the municipal waste incineration. The content of undecomposed PCBs, dioxins, and other hazardous waste in all secondary products of treatment (off gases; slag; secondary fly ash; process water used for slag granulation) was analyzed by different methods. Performed analytical investigations showed high ecological degree of PCB decomposition in the plant of plasma-thermal treatment of ashes after incinerators.

  13. Immunity of PCB transplacental Yu-Cheng children in Taiwan

    SciTech Connect

    Lan, Shou Jen; Yen, Yea Yin; Chen, Eng Rin; Ko, Ying Chin ); Lan, Joung Liang )

    1990-02-01

    Up to now, there has been no studies about the immune status of PCB transplacental Yu-Cheng babies. In an earlier study, Yu-Cheng babies were reported to have a high infant mortality rate. It was reported that these babies would easily catch cold, experience diarrhea and abdominal pains. Recently, it was found that the bronchitis rate of Yu-Cheng babies is higher than in control babies. Because of high risk of infection, it is presumed that these babies might suffer immunosuppression to a certain extent. According to these findings, investigations into the immune functions of PCB transplacental Yu-Cheng babies are needed.

  14. Environmental projects. Volume 1: Polychlorinated biphenyl (PCB) abatement program

    NASA Technical Reports Server (NTRS)

    Kushner, L.

    1987-01-01

    Six large parabolic dish antennas are located at the Goldstone Deep Space Communications Complex north of Barstow, California. Some of the ancillary electrical equipment of thes Deep Space Stations, particularly transformers and power capicitors, were filled with stable, fire-retardant, dielectric fluids containing substances called polychlorobiphenyls (PCBs). Because the Environmental Protection Agency has determined that PCBs are environmental pollutants toxic to humans, all NASA centers have been asked to participate in a PCB-abatement program. Under the supervision of JPL's Office of Telecommunications and Data Acquisition, a two-year long PCB-abatement program has eliminated PCBs from the Goldstone Complex.

  15. 40 CFR 761.62 - Disposal of PCB bulk product waste.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Disposal of PCB bulk product waste..., AND USE PROHIBITIONS Storage and Disposal § 761.62 Disposal of PCB bulk product waste. PCB bulk product waste shall be disposed of in accordance with paragraph (a), (b), or (c) of this section....

  16. 40 CFR 761.62 - Disposal of PCB bulk product waste.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Disposal of PCB bulk product waste..., AND USE PROHIBITIONS Storage and Disposal § 761.62 Disposal of PCB bulk product waste. PCB bulk product waste shall be disposed of in accordance with paragraph (a), (b), or (c) of this section....

  17. 40 CFR 761.62 - Disposal of PCB bulk product waste.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Disposal of PCB bulk product waste..., AND USE PROHIBITIONS Storage and Disposal § 761.62 Disposal of PCB bulk product waste. PCB bulk product waste shall be disposed of in accordance with paragraph (a), (b), or (c) of this section....

  18. 40 CFR 761.298 - Decisions based on PCB concentration measurements resulting from sampling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Decisions based on PCB concentration... Cleanup and On-Site Disposal of Bulk PCB Remediation Waste and Porous Surfaces in Accordance With § 761.61(a)(6) § 761.298 Decisions based on PCB concentration measurements resulting from sampling. (a)...

  19. 40 CFR 261.8 - PCB wastes regulated under Toxic Substance Control Act.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 false PCB wastes regulated under Toxic... (CONTINUED) SOLID WASTES (CONTINUED) IDENTIFICATION AND LISTING OF HAZARDOUS WASTE General § 261.8 PCB wastes regulated under Toxic Substance Control Act. The disposal of PCB-containing dielectric fluid and...

  20. 40 CFR 761.298 - Decisions based on PCB concentration measurements resulting from sampling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Decisions based on PCB concentration... Cleanup and On-Site Disposal of Bulk PCB Remediation Waste and Porous Surfaces in Accordance With § 761.61(a)(6) § 761.298 Decisions based on PCB concentration measurements resulting from sampling. (a)...

  1. 40 CFR 761.295 - Reporting and recordkeeping of the PCB concentrations in samples.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Reporting and recordkeeping of the PCB... On-Site Disposal of Bulk PCB Remediation Waste and Porous Surfaces in Accordance With § 761.61(a)(6) § 761.295 Reporting and recordkeeping of the PCB concentrations in samples. (a) Report all...

  2. 40 CFR 761.295 - Reporting and recordkeeping of the PCB concentrations in samples.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Reporting and recordkeeping of the PCB... On-Site Disposal of Bulk PCB Remediation Waste and Porous Surfaces in Accordance With § 761.61(a)(6) § 761.295 Reporting and recordkeeping of the PCB concentrations in samples. (a) Report all...

  3. 40 CFR 261.8 - PCB wastes regulated under Toxic Substance Control Act.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 false PCB wastes regulated under Toxic... (CONTINUED) SOLID WASTES (CONTINUED) IDENTIFICATION AND LISTING OF HAZARDOUS WASTE General § 261.8 PCB wastes regulated under Toxic Substance Control Act. The disposal of PCB-containing dielectric fluid and...

  4. 40 CFR 761.316 - Interpreting PCB concentration measurements resulting from this sampling scheme.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Interpreting PCB concentration... § 761.79(b)(3) § 761.316 Interpreting PCB concentration measurements resulting from this sampling... composite is 20 µg/100 cm2, then the entire 9.5 square meters has a PCB surface concentration of 20...

  5. 40 CFR 761.295 - Reporting and recordkeeping of the PCB concentrations in samples.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Reporting and recordkeeping of the PCB... On-Site Disposal of Bulk PCB Remediation Waste and Porous Surfaces in Accordance With § 761.61(a)(6) § 761.295 Reporting and recordkeeping of the PCB concentrations in samples. (a) Report all...

  6. 40 CFR 761.298 - Decisions based on PCB concentration measurements resulting from sampling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Decisions based on PCB concentration... Cleanup and On-Site Disposal of Bulk PCB Remediation Waste and Porous Surfaces in Accordance With § 761.61(a)(6) § 761.298 Decisions based on PCB concentration measurements resulting from sampling. (a)...

  7. 40 CFR 761.63 - PCB household waste storage and disposal.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false PCB household waste storage and..., AND USE PROHIBITIONS Storage and Disposal § 761.63 PCB household waste storage and disposal. PCB... to manage municipal or industrial solid waste, or in a facility with an approval to dispose of...

  8. 40 CFR 261.8 - PCB wastes regulated under Toxic Substance Control Act.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false PCB wastes regulated under Toxic... (CONTINUED) SOLID WASTES (CONTINUED) IDENTIFICATION AND LISTING OF HAZARDOUS WASTE General § 261.8 PCB wastes regulated under Toxic Substance Control Act. The disposal of PCB-containing dielectric fluid and...

  9. 40 CFR 261.8 - PCB wastes regulated under Toxic Substance Control Act.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false PCB wastes regulated under Toxic... (CONTINUED) SOLID WASTES (CONTINUED) IDENTIFICATION AND LISTING OF HAZARDOUS WASTE General § 261.8 PCB wastes regulated under Toxic Substance Control Act. The disposal of PCB-containing dielectric fluid and...

  10. 40 CFR 761.63 - PCB household waste storage and disposal.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false PCB household waste storage and..., AND USE PROHIBITIONS Storage and Disposal § 761.63 PCB household waste storage and disposal. PCB... to manage municipal or industrial solid waste, or in a facility with an approval to dispose of...

  11. 40 CFR 761.63 - PCB household waste storage and disposal.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false PCB household waste storage and..., AND USE PROHIBITIONS Storage and Disposal § 761.63 PCB household waste storage and disposal. PCB... to manage municipal or industrial solid waste, or in a facility with an approval to dispose of...

  12. 40 CFR 761.316 - Interpreting PCB concentration measurements resulting from this sampling scheme.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Interpreting PCB concentration... § 761.79(b)(3) § 761.316 Interpreting PCB concentration measurements resulting from this sampling... composite is 20 µg/100 cm2, then the entire 9.5 square meters has a PCB surface concentration of 20...

  13. 40 CFR 761.316 - Interpreting PCB concentration measurements resulting from this sampling scheme.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Interpreting PCB concentration... § 761.79(b)(3) § 761.316 Interpreting PCB concentration measurements resulting from this sampling... composite is 20 µg/100 cm2, then the entire 9.5 square meters has a PCB surface concentration of 20...

  14. 77 FR 11533 - Anniston PCB Superfund Site, Anniston, Calhoun County, Alabama; Notice of Amended Settlement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-27

    ... AGENCY Anniston PCB Superfund Site, Anniston, Calhoun County, Alabama; Notice of Amended Settlement... Agency has entered into a settlement for past response costs concerning the Anniston PCB Superfund Site... available from Ms. Paula V. Painter. Submit your comments by Site name Anniston PCB by one of the...

  15. 40 CFR 761.265 - Sampling bulk PCB remediation waste and porous surfaces.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Sampling bulk PCB remediation waste..., DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Cleanup Site Characterization Sampling for PCB Remediation Waste in Accordance with § 761.61(a)(2) § 761.265 Sampling bulk PCB remediation waste and porous...

  16. 40 CFR 761.63 - PCB household waste storage and disposal.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false PCB household waste storage and..., AND USE PROHIBITIONS Storage and Disposal § 761.63 PCB household waste storage and disposal. PCB... to manage municipal or industrial solid waste, or in a facility with an approval to dispose of...

  17. 40 CFR 761.298 - Decisions based on PCB concentration measurements resulting from sampling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Decisions based on PCB concentration....61(a)(6) § 761.298 Decisions based on PCB concentration measurements resulting from sampling. (a) For grid samples which are chemically analyzed individually, the PCB concentration applies to the area...

  18. 40 CFR 761.298 - Decisions based on PCB concentration measurements resulting from sampling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Decisions based on PCB concentration....61(a)(6) § 761.298 Decisions based on PCB concentration measurements resulting from sampling. (a) For grid samples which are chemically analyzed individually, the PCB concentration applies to the area...

  19. 40 CFR 761.63 - PCB household waste storage and disposal.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false PCB household waste storage and..., AND USE PROHIBITIONS Storage and Disposal § 761.63 PCB household waste storage and disposal. PCB household waste, as defined at § 761.3, managed in a facility permitted, licensed, or registered by a...

  20. 210Pb-derived history of PAH and PCB accumulation in sediments of a tropical inner lagoon (Las Matas, Gulf of Mexico) near a major oil refinery

    NASA Astrophysics Data System (ADS)

    Ruiz-Fernández, Ana Carolina; Sprovieri, Mario; Piazza, Rossano; Frignani, Mauro; Sanchez-Cabeza, Joan-Albert; Feo, Maria Luisa; Bellucci, Luca Giorgio; Vecchiato, Marco; Pérez-Bernal, Libia Hascibe; Páez-Osuna, Federico

    2012-04-01

    Concentrations of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were measured in a sediment core from the tropical freshwater inner lagoon of Las Matas, near the petroleum industrial area of Minatitlán-Coatzacoalcos, in the Gulf of Mexico. A 210Pb-derived chronology was used to reconstruct the historical PAH and PCB accumulation in the site during one century (1906-2005). Both geochemical and sedimentological data indicated that a major change occurred in 1947 ± 4, including a shift to coarser sediments and a significant decrease of Al, Li, Fe, organic C and total N contents. This was likely due to the changes in hydrology caused by the confinement of Las Matas Lagoon due to the construction of the Trans-Isthmus road in 1946. PAHs in these samples show relatively low concentrations (259-1176 ng g-1), and the congener relative abundances indicate the influence of pyrogenic (petroleum combustion) sources. Total PCB concentrations in the sediments ranged from 24 to 77 ng g-1, and are composed by low chlorinated PCBs, with 3- and 4-CB as the prevalent species (51-65% and 29-40%, respectively). PAHs and PCBs were detected at depths corresponding to the early 1900s, when Minatitlán refinery started operations, although their time evolution appears to be influenced by different accumulation processes. The PCB background is most likely produced by the combustion of natural organic matter, and an industrial contribution can be recognized when normalizing with OC contents. We concluded that atmospheric deposition is the most significant source of PAHs and PCBs for this water body. This study also provided evidence of the alteration of the wetlands surrounding this industrial area due to urbanization; the fragmentation and alteration of Las Matas Lagoon hydrology contributes to the gradual loss of the wetlands in the zone.

  1. Delayed effects of developmental exposure to low levels of the aryl hydrocarbon receptor agonist 3,3',4,4',5-pentachlorobiphenyl (PCB126) on adult zebrafish behavior.

    PubMed

    Glazer, Lilah; Hahn, Mark E; Aluru, Neelakanteswar

    2016-01-01

    Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants. The most toxic PCBs are the non-ortho-substituted ("dioxin-like") congeners that act through the aryl hydrocarbon receptor (AHR) pathway. In humans, perinatal exposure to dioxin-like PCBs is associated with neurodevelopmental toxicity in children. Yet, the full potential for later-life neurobehavioral effects that result from early-life low level exposure to dioxin-like PCBs is not well understood. The objective of this study was to determine the effects of developmental exposure to low levels of dioxin-like PCBs on early- and later-life behavioral phenotypes using zebrafish as a model system. We exposed zebrafish embryos to either vehicle (DMSO) or low concentrations of PCB126 (0.3, 0.6, 1.2nM) for 20h (4-24h post fertilization), and then reared them to adulthood in clean water. Locomotor activity was tested at two larval stages (7 and 14 days post fertilization). Adult fish were tested for anxiety-related behavior using the novel tank and shoaling assays. Adult behavioral assays were repeated several times on the same group of fish and effects on intra- and inter-trial habituation were determined. While there was no effect of PCB126 on larval locomotor activity in response to changes in light conditions, developmental exposure to PCB126 resulted in impaired short- and long-term habituation to a novel environment in adult zebrafish. Cyp1a induction was measured as an indicator for AHR activation. Despite high induction at early stages, cyp1a expression was not induced in the brains of developmentally exposed adult fish that showed altered behavior, suggesting that AHR was not activated at this stage. Our results demonstrate the effectiveness of the zebrafish model in detecting subtle and delayed behavioral effects resulting from developmental exposure to an environmental contaminant. PMID:26616910

  2. FACILITIES EVALUATION OF HIGH EFFICIENCY BOILER DESTRUCTION PCB WASTE

    EPA Science Inventory

    The report gives results of an evaluation of destruction in two different high-efficiency boilers (as an alternative to landfill disposal) of waste (a rendering plant byproduct, yellow grease) found to be contaminated by PCBs from a transformer leak. (The PCB content--under 500 p...

  3. Polymer multimode waveguide optical and electronic PCB manufacturing

    NASA Astrophysics Data System (ADS)

    Selviah, David R.

    2009-02-01

    The paper describes the research in the Â#1.3 million IeMRC Integrated Optical and Electronic Interconnect PCB Manufacturing (OPCB) Flagship Project in which 8 companies and 3 universities carry out collaborative research and which was formed and is technically led by the author. The consortium's research is aimed at investigating a range of fabrication techniques, some established and some novel, for fabricating polymer multimode waveguides from several polymers, some formulations of which are being developed within the project. The challenge is to develop low cost waveguide manufacturing techniques compatible with commercial PCB manufacturing and to reduce their alignment cost. The project aims to take the first steps in making this hybrid optical waveguide and electrical copper track printed circuit board disruptive technology widely available by establishing and incorporating waveguide design rules into commercial PCB layout software and transferring the technology for fabricating such boards to a commercial PCB manufacturer. To focus the research the project is designing an optical waveguide backplane to tight realistic constraints, using commercial layout software with the new optical design rules, for a demonstrator into which 4 daughter cards are plugged, each carrying an aggregate of 80 Gb/s data so that each waveguide carries 10 Gb/s.

  4. Recovery of a PCB-Contaminated Creek Fish Community

    EPA Science Inventory

    Polychlorinated Biphenyls (PCBs) from the Sangamo-Weston Superfund Site near Clemson, South Carolina, USA, were released into the Twelvemile Creek until the early 1990s. PCB concentrations in fish in this creek have remained elevated: levels in six target fish species are still a...

  5. EVALUATION OF PROTOCOLS FOR PESTICIDES AND PCB'S IN RAW WASTEWATER

    EPA Science Inventory

    The general EPA protocol for screening industrial effluents for priority pollutants (Federal Register 38, No. 75, Part II), has been tested for its applicability to the analysis of the priority pollutant pesticides and PCB's in raw wastewater. Raw wastewater from the municipal se...

  6. The Effect of Intrauterine PCB Exposure on Visual Recognition Memory.

    ERIC Educational Resources Information Center

    Jacobson, Sandra W.; And Others

    1985-01-01

    Measures of prenatal exposure in 123 infants to polychlorinated biphenyls (PCBs), cord serum PCB level, and maternal report of contaminated fish consumption predicted less preference for a novel stimulus on Fagan's test of visual recognition memory (VRM) at 7 months. Preference for novelty decreased in a dose-dependent fashion and postnatal…

  7. ENVIRONMENTAL PCB AND PESTICIDE EXPOSURE AND RISK OF ENDOMETRIOSIS

    EPA Science Inventory

    Environmental PCB and Pesticide Exposure and Risk of Endometriosis

    Germaine M. Buck1, John M. Weiner2, Hebe Greizerstein3, Brian Whitcomb1, Enrique Schisterman1, Paul Kostyniak3, Danelle Lobdell4, Kent Crickard5, and Ralph Sperrazza5

    1Epidemiology Branch, Division o...

  8. 40 CFR 761.61 - PCB remediation waste.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false PCB remediation waste. 761.61 Section 761.61 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT POLYCHLORINATED BIPHENYLS (PCBs) MANUFACTURING, PROCESSING, DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Storage and Disposal § 761.61...

  9. 40 CFR 761.61 - PCB remediation waste.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false PCB remediation waste. 761.61 Section 761.61 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT POLYCHLORINATED BIPHENYLS (PCBs) MANUFACTURING, PROCESSING, DISTRIBUTION IN COMMERCE, AND USE PROHIBITIONS Storage and Disposal § 761.61...

  10. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Tolerances for polychlorinated biphenyls (PCB's). 109.30 Section 109.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION UNAVOIDABLE CONTAMINANTS IN FOOD FOR HUMAN CONSUMPTION...

  11. 21 CFR 109.30 - Tolerances for polychlorinated biphenyls (PCB's).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Tolerances for polychlorinated biphenyls (PCB's). 109.30 Section 109.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION UNAVOIDABLE CONTAMINANTS IN FOOD FOR HUMAN CONSUMPTION AND FOOD-PACKAGING MATERIAL Tolerances...

  12. 40 CFR 761.2 - PCB concentration assumptions for use.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... must assume that a capacitor manufactured prior to July 2, 1979, whose PCB concentration is not established contains ≥500 ppm PCBs. Any person may assume that a capacitor manufactured after July 2, 1979, is... capacitor contains ≥500 ppm PCBs. Any person may assume that a capacitor marked at the time of...

  13. 40 CFR 761.2 - PCB concentration assumptions for use.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... must assume that a capacitor manufactured prior to July 2, 1979, whose PCB concentration is not established contains ≥500 ppm PCBs. Any person may assume that a capacitor manufactured after July 2, 1979, is... capacitor contains ≥500 ppm PCBs. Any person may assume that a capacitor marked at the time of...

  14. 40 CFR 761.2 - PCB concentration assumptions for use.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... must assume that a capacitor manufactured prior to July 2, 1979, whose PCB concentration is not established contains ≥500 ppm PCBs. Any person may assume that a capacitor manufactured after July 2, 1979, is... capacitor contains ≥500 ppm PCBs. Any person may assume that a capacitor marked at the time of...

  15. 40 CFR 761.2 - PCB concentration assumptions for use.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... must assume that a capacitor manufactured prior to July 2, 1979, whose PCB concentration is not established contains ≥500 ppm PCBs. Any person may assume that a capacitor manufactured after July 2, 1979, is... capacitor contains ≥500 ppm PCBs. Any person may assume that a capacitor marked at the time of...

  16. Vapor-phase and particulate-associated pesticides and PCB concentrations in eastern North Dakota air samples

    SciTech Connect

    Hawthorne, S.B.; Miller, D.J.; Louie, P.K.K.

    1996-05-01

    Vapor-phase and suspended particulate (<50 {mu}m) samples were collected on polyurethane foam (PUF) and quartz fiber filters in rural North Dakota to determine the air concentrations of pesticides in an area where agriculture is a primary source of semivolatile pollutants. Samples were collected at two sites from 1992 to 1994 that were at least 0.4 km from the nearest farmed fields and known application of pesticides, and analyzed for 22 different organochlorine, triazine, and acid herbicide pesticides. Fourteen pesticides were found above the detection limits (typically <1 pg/m{sup 3}). Concentrations of polychlorinated biphenyl (PCB) congeners were much lower (<50 pg/m{sup 3} in all cases) than many of the pesticides. These results demonstrate that pesticides are among the most prevalent chlorinated semivolatile pollutants present in rural North Dakota, that significant transport of pesticides occurs both in the vapor-phase and on suspended particulate matter, and that blown soil may be a significant mechanism for introducing pesticides into surface and ground waters. 32 refs., 2 figs., 4 tabs.

  17. Field Metabolic Rate and PCB Adipose Tissue Deposition Efficiency in East Greenland Polar Bears Derived from Contaminant Monitoring Data

    PubMed Central

    Pavlova, Viola; Nabe-Nielsen, Jacob; Dietz, Rune; Svenning, Jens-Christian; Vorkamp, Katrin; Rigét, Frank Farsø; Sonne, Christian; Letcher, Robert J.; Grimm, Volker

    2014-01-01

    Climate change will increasingly affect the natural habitat and diet of polar bears (Ursus maritimus). Understanding the energetic needs of polar bears is therefore important. We developed a theoretical method for estimating polar bear food consumption based on using the highly recalcitrant polychlorinated biphenyl (PCB) congener, 2,2′,4,4′,55-hexaCB (CB153) in bear adipose tissue as an indicator of food intake. By comparing the CB153 tissue concentrations in wild polar bears with estimates from a purposely designed individual-based model, we identified the possible combinations of field metabolic rates (FMR) and CB153 deposition efficiencies in East Greenland polar bears. Our simulations indicate that if 30% of the CB153 consumed by polar bear individuals were deposited into their adipose tissue, the corresponding FMR would be only two times the basal metabolic rate. In contrast, if the modelled CB153 deposition efficiency were 10%, adult polar bears would require six times more energy than that needed to cover basal metabolism. This is considerably higher than what has been assumed for polar bears in previous studies though it is similar to FMRs found in other marine mammals. An implication of this result is that even relatively small reductions in future feeding opportunities could impact the survival of East Greenland polar bears. PMID:25101837

  18. Field metabolic rate and PCB adipose tissue deposition efficiency in East Greenland polar bears derived from contaminant monitoring data.

    PubMed

    Pavlova, Viola; Nabe-Nielsen, Jacob; Dietz, Rune; Svenning, Jens-Christian; Vorkamp, Katrin; Rigét, Frank Farsø; Sonne, Christian; Letcher, Robert J; Grimm, Volker

    2014-01-01

    Climate change will increasingly affect the natural habitat and diet of polar bears (Ursus maritimus). Understanding the energetic needs of polar bears is therefore important. We developed a theoretical method for estimating polar bear food consumption based on using the highly recalcitrant polychlorinated biphenyl (PCB) congener, 2,2',4,4',55-hexaCB (CB153) in bear adipose tissue as an indicator of food intake. By comparing the CB153 tissue concentrations in wild polar bears with estimates from a purposely designed individual-based model, we identified the possible combinations of field metabolic rates (FMR) and CB153 deposition efficiencies in East Greenland polar bears. Our simulations indicate that if 30% of the CB153 consumed by polar bear individuals were deposited into their adipose tissue, the corresponding FMR would be only two times the basal metabolic rate. In contrast, if the modelled CB153 deposition efficiency were 10%, adult polar bears would require six times more energy than that needed to cover basal metabolism. This is considerably higher than what has been assumed for polar bears in previous studies though it is similar to FMRs found in other marine mammals. An implication of this result is that even relatively small reductions in future feeding opportunities could impact the survival of East Greenland polar bears. PMID:25101837

  19. The Transcriptional Effects of PCB118 and PCB153 on the Liver, Adipose Tissue, Muscle and Colon of Mice: Highlighting of Glut4 and Lipin1 as Main Target Genes for PCB Induced Metabolic Disorders

    PubMed Central

    Mesnier, Aurélia; Champion, Serge; Louis, Laurence; Sauzet, Christophe; May, Phealay; Portugal, Henri; Benbrahim, Karim; Abraldes, Joelle; Alessi, Marie-Christine; Amiot-Carlin, Marie-Josephe; Peiretti, Franck; Piccerelle, Philippe; Nalbone, Gilles; Villard, Pierre-Henri

    2015-01-01

    Epidemiological studies have associated environmental exposure to polychlorinated biphenyls (PCBs) with an increased risk of type 2 diabetes; however, little is known about the underlying mechanisms involved in the metabolic side-effects of PCB. Our study evaluated the transcriptional effects of a subchronic exposure (gavage at Day 0 and Day 15 with 10 or 100 μmol/Kg bw) to PCB118 (dioxin-like PCB), PCB153 (non-dioxin-like PCB), or an equimolar mixture of PCB118 and PCB153 on various tissues (liver, visceral adipose tissue, muscle, and colon) in mice. Our results showed that a short-term exposure to PCB118 and/or PCB153 enhanced circulating triglyceride levels but did not affect glycemia. Among the studied tissues, we did not observe any modification of the expression of inflammation-related genes, such as cytokines or chemokines. The main transcriptional effects were observed in visceral adipose and liver tissues. We found a downregulation of lipin1 and glut4 expression in these two target organs. In adipose tissue, we also showed a downregulation of Agpat2, Slc25a1, and Fasn. All of these genes are involved in lipid metabolism and insulin resistance. In muscles, we observed an induction of CnR1 and Foxo3 expression, which may be partly involved in PCB metabolic effects. In summary, our results suggest that lipin1 and glut4, notably in adipose tissue, are the main targeted genes in PCB-induced metabolic disorders, however, further studies are required to fully elucidate the mechanisms involved. PMID:26086818

  20. The Transcriptional Effects of PCB118 and PCB153 on the Liver, Adipose Tissue, Muscle and Colon of Mice: Highlighting of Glut4 and Lipin1 as Main Target Genes for PCB Induced Metabolic Disorders.

    PubMed

    Mesnier, Aurélia; Champion, Serge; Louis, Laurence; Sauzet, Christophe; May, Phealay; Portugal, Henri; Benbrahim, Karim; Abraldes, Joelle; Alessi, Marie-Christine; Amiot-Carlin, Marie-Josephe; Peiretti, Franck; Piccerelle, Philippe; Nalbone, Gilles; Villard, Pierre-Henri

    2015-01-01

    Epidemiological studies have associated environmental exposure to polychlorinated biphenyls (PCBs) with an increased risk of type 2 diabetes; however, little is known about the underlying mechanisms involved in the metabolic side-effects of PCB. Our study evaluated the transcriptional effects of a subchronic exposure (gavage at Day 0 and Day 15 with 10 or 100 μmol/Kg bw) to PCB118 (dioxin-like PCB), PCB153 (non-dioxin-like PCB), or an equimolar mixture of PCB118 and PCB153 on various tissues (liver, visceral adipose tissue, muscle, and colon) in mice. Our results showed that a short-term exposure to PCB118 and/or PCB153 enhanced circulating triglyceride levels but did not affect glycemia. Among the studied tissues, we did not observe any modification of the expression of inflammation-related genes, such as cytokines or chemokines. The main transcriptional effects were observed in visceral adipose and liver tissues. We found a downregulation of lipin1 and glut4 expression in these two target organs. In adipose tissue, we also showed a downregulation of Agpat2, Slc25a1, and Fasn. All of these genes are involved in lipid metabolism and insulin resistance. In muscles, we observed an induction of CnR1 and Foxo3 expression, which may be partly involved in PCB metabolic effects. In summary, our results suggest that lipin1 and glut4, notably in adipose tissue, are the main targeted genes in PCB-induced metabolic disorders, however, further studies are required to fully elucidate the mechanisms involved. PMID:26086818

  1. Congenic mapping and candidate sequencing of susceptibility genes for Type 1 diabetes in the NOD mouse.

    PubMed

    Ikegami, Hiroshi; Fujisawa, Tomomi; Makino, Susumu; Ogihara, Toshio

    2003-11-01

    Inheritance of type 1 diabetes is polygenic with a major susceptibility gene located in the major histocompatibility complex (MHC). In addition to MHC-linked susceptibility, a number of susceptibility genes have been mapped outside the MHC in both humans and animal models. In order to localize and identify susceptibility genes for type 1 diabetes, we have developed a series of congenic strains in which either susceptibility intervals from the NOD mouse, a mouse model of type 1 diabetes, were introgressed onto control background genes or protective intervals from control strains were introgressed onto NOD background genes. NOD. CTS-H-2 congenic mice, which possess recombinant MHC with NOD alleles at class II A and E genes, which are candidates for Idd1, revealed that Idd1 consists of multiple components, one in class II (Idd1) and the other adjacent to, but distinct from, Idd1 (Idd16). Phenotypes of NOD. IIS-Idd3 congenic mice, which share the same alleles at both Il2 and Il21 as the NOD mouse, were indistinguishable from the NOD parental strain, indicating that both Il2 and Il21 are candidates for Idd3. In contrast, NOD. IIS-Idd10 congenic mice, which share the same alleles at Fcgr1, a previous candidate for Idd10, as the NOD mouse, were protected from type 1 diabetes, suggesting that Fcgr1 may not be responsible for the Idd10 effect. These data suggest that the use of strain colony closely related to a disease model to find the same candidate mutation on different haplotypes and make congenic strains with this recombinant chromosome, termed ancestral haplotype congenic mapping, is an effective strategy for fine mapping and identification of genes responsible for complex traits. PMID:14679059

  2. The potential of PCB photochemistry at Moccasin Bend

    SciTech Connect

    Hinton, M.M.; Beck, M.J.

    1993-03-30

    The TVA/EPRI Tailored Collaborative Project {open_quotes}Biotransformation of Polychlorinated Biphenyls (PCBS) in Contaminated Soils{close_quotes}, has as its objective biotransformation of PCB contaminated soils at utility sites (Phase I Report March 1992). However, there is recognition of the existence of other types of nonmetabolic alterations of PCBs in the contaminated soils. Of these nonmetabolic alterations, photoalteration is of special interest to the project. Photoalteration has the potential for enhancing PCB transformation with little intervention and little harm to the microbial community. PCBs have pervaded the environment, and the paucity of knowledge about their chemistry is becoming readily apparent. Although PCBs are quite resistant to degradation, photolysis, which is a chemical decomposition process that is induced by radiant energy, may be important in the environmental chemistry of PCBS. The photochemical degradation of PCBs may affect atmospheric levels of contaminants and photolabile chemicals that reside in water bodies or on surfaces, as for example, on leaves and vegetation. Chemicals present in the environment can undergo direct or indirect phototransformation which includes photosensitized degradation and oxygenation as well as photoinduced degradation. Photoalteration is produced by either artificial light or by light from the sun. Ultraviolet radiation (UV) is known to induce chemical reactions in many chlorinated hydrocarbons under laboratory conditions. To determine whether PCB alterations are the result of light-catalyzed reactions, it is necessary to verify PCB photolysis, to define the products of photolysis, and to explain the conditions and mechanisms necessary to produce such reactions. It is the purpose of this report to review the literature concerning photoalteration of PCBs and the potential role of this mechanism to facilitate PCB remediation at the research site.

  3. Acute hepatotoxicity of ethylene and halogenated ethylenes after PCB pretreatment.

    PubMed

    Conolly, R B; Jaeger, R J

    1977-12-01

    Previous studies from our laboratory have shown that ethylene, vinyl fluoride monomer (VFM), vinyl chloride monomer (VCM), and vinyl bromide monomer (VBM) are all acutely hepatotoxic in rats pretreated with polychlorinated biphenyl (PCB). The time course of hepatic injury development after exposure and several parameters, environmental and chemical, affecting this toxicity were evaluated in the work reported here. Liver injury, as measured by serum alanine-alpha-ketoglutarate transaminase (SAKT) or sorbitol dehydrogenase (SDH), develops progressively over a 24-hr period following a 4-hr inhalation exposure of PCB-pretreated rats to ethylene or VCM. Environmental temperature during exposure to VCM does not affect hepatotoxicity or mortality below 30.3 degrees C. At 33.8 degrees C, however, mortality and SAKT are dramatically increased. Overnight fasting, which depletes hepatic glutathione (GSH) of PCB-pretreated rats before exposure to ethylene or VCM, significantly increases the hepatotoxicity of these compounds as measured by SDH. The combined effects of fasting and of trichloropropane epoxide (TCPE), an inhibitor of epoxide hydrase (EH), were also examined. TCPE treatment of fasted PCB-pretreated rats immediately before exposure was synergistic in increasing the acute toxicity of ethylene and VCM. TCPE increased mortality in fed or fasted rats exposed to VFM, but there was no effect of fasting alone. Both fasting and TCPE increased the sensitivity of PCB-pretreated rats to VBM, but there was not a clearly synergistic effect of fasting plus TCPE. These data suggest that the acute toxicity of these compounds is mediated through epoxide intermediates. PMID:417916

  4. PCB bioavailability control in Lumbriculus variegatus through different modes of activated carbon addition to sediments

    SciTech Connect

    Xueli Sun; Upal Ghosh

    2007-07-01

    PCB bioavailability to a freshwater oligochaete (Lumbriculus variegatus) was studied using sediments from a PCB-impacted river that was treated with different modes of granular activated carbon (GAC) addition. The GAC used was bituminous coal-based type TOP. For sediment treated with 2.6% GAC and mixed for 2 min prior to L. variegatus addition, the reduction in total PCB biouptake was 70% for 75-300 {mu}m size carbon, and 92% for the 45-180 {mu}m size carbon. For the case where the GAC was placed as a thin layer on top of the sediments without mixing, the reduction in total PCB uptake was 70%. PCB biouptake kinetics study using treated and untreated sediment showed that the maximum PCB uptake in tissue was achieved at 28 days and decreased after that time. Although the absolute uptake of PCB changed over time, the percent reduction in total PCB uptake upon GAC amendment remained constant after the first few days. Our results indicated that PCB bioavailability was reduced upon the addition and little or no mixing of GAC into sediments. PCB aqueous equilibrium concentration and desorption rates were greatly reduced after GAC amendment, indicating reductions in the two primary mechanisms of PCB bioavailability in sediments: chemical activity and chemical accessibility. 29 refs., 5 figs., 1 tab.

  5. CEREBROVASCULAR TOXICITY OF PCB153 IS ENHANCED BY BINDING TO SILICA NANOPARTICLES

    PubMed Central

    Zhang, Bei; Chen, Lei; Choi, Jeong June; Hennig, Bernhard; Toborek, Michal

    2012-01-01

    Environmental polychlorinated biphenyls (PCBs) are frequently bound onto nanoparticles (NPs). However, the toxicity and health effects of PCBs assembled onto nanoparticles are unknown. The aim of this study was to study the hypothesis that binding PCBs to silica NPs potentiates PCB-induced cerebrovascular toxicity and brain damage in an experimental stroke model. Mice (C57BL/6, males, 12-week-old) were exposed to PCB153 bound to NPs (PCB153-NPs), PCB153, or vehicle. PCB153 was administered in the amount of 5 ng/g body weight. A group of treated animals was subjected to a 40 min ischemia, followed by a 24 h reperfusion. The blood-brain barrier (BBB) permeability, brain infarct volume, expression of tight junction (TJ) proteins, and inflammatory mediators were assessed. As compared to controls, a 24 h exposure to PCB153-NPs injected into cerebral vasculature resulted in significant elevation of the BBB permeability, disruption of TJ protein expression, increased proinflammatory responses, and enhanced monocyte transmigration in mouse brain capillaries. Importantly, exposure to PCB153-NPs increased stroke volume and potentiated brain damage in mice subjected to ischemia/reperfusion. A long-term (30 days) oral exposure to PCB153-NPs resulted in a higher PCB153 content in the abdominal adipose tissue and amplified adhesion of leukocytes to the brain endothelium as compared to treatment with PCB153 alone. This study provides the first evidence that binding to NPs increases cerebrovascular toxicity of environmental toxicants, such as PCB153. PMID:23081707

  6. Determinations of PCB within a project to develop cleanup methods for PCB-containing elastic sealant used in outdoor joints between concrete blocks in buildings.

    PubMed

    Sundahl, M; Sikander, E; Ek-Olausson, B; Hjorthage, A; Rosell, L; Tornevall, M

    1999-08-01

    Determinations of PCB were carried out as part of a project aimed at developing cleanup methods for PCB-containing elastic sealant used in outdoor joints between concrete blocks. The goals of the project were to develop methods, which minimise the spread of PCB to the outdoor environment and to indoor air, and which keep the PCB levels as low as reasonably possible in the workplace environment whilst removing the elastic sealant. The following PCB determinations were carried out: (1) concentration in the elastic sealant; (2) concentration in the concrete close to the sealant; (3) concentration in soil; (4) concentration in the indoor air; and (5) concentration in the air in the workplace environment. The cleanup process consisted of a number of different steps: (1) cutting the elastic sealant with an oscillating knife; (2) grinding the concrete with a mechanical machine; (3) sawing the concrete with a mechanical saw and (4) cutting the concrete with a mechanical chisel. In all these different steps a high capacity vacuum cleaner connected to the machines was used. The elastic sealant contained 4.7 to 8.1% total PCB of a technical product with a composition most similar to Clophene A40. The concrete close to the sealant (first 2 mm) contained 0.12 and 1.7% total PCB at two different places. The pattern of the PCB in the concrete resembled that of the sealant. PCB concentrations in the soil from the ground close to the building were 0.1 and 0.3 ppm at two different places before the remedial action. The source of the PCB in the soil is most likely the sealant as the PCB pattern is similar for the two materials. The PCB levels in the workplace air at the beginning of the project, when the techniques were not fully developed, were generally above the occupational exposure limit of 10 micrograms m-3 (up to 120 micrograms m-3). Later when the techniques were optimised to better take care of dust and gases produced during the cutting and grinding etc., the levels were

  7. DIFFERENTIAL EFFECTS OF TWO LOTS OF AROCLOR 1254R: CONGENER ANALYSIS AND NEUROCHEMICAL ENDPOINTS.

    EPA Science Inventory

    Introduction
    Polychlorinated biphenyls (PCBs) are widely used in industry as heat transfer and dielectric fluids for transformers and capacitors1. PCBs were commercially produced as AroclorR mixtures in USA by the chlorination of biphenyl. Although all 209 congeners can be syn...

  8. Trait responses of invasive aquatic Ludwigia congeners (Onagraceae): effects of ploidy and resource availability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding traits underlying colonization and niche breadth of invasive plants is key to developing sustainable management solutions to curtail invasions at the establishment phase, when efforts are often most effective. The aim of this study was to evaluate how two invasive congeners differing i...

  9. MODELLING OF POLYCHLORINATED-DIOXIN AND -FURAN CONGENER PROFILES FROM MUNICIPAL WASTE COMBUSTION

    EPA Science Inventory

    The paper discusses a model, based on experimental data, that was developed to describe the profile of polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) congeners formed in the duct region of a pilot-scale combustor simulating large-scale municipal w...

  10. Thiophene congeners of morpholine and allylamine type antifungals--syntheses and biological activities.

    PubMed

    Bracher, F; Papke, T

    1995-08-01

    A thiophene analogue 8 of the antifungal drug amorolfine (1) was prepared starting from the alcohol 5. In addition, congeners of naftifine, terbinafine and butenafine, in which the naphthalene ring is replaced by a branched thienylalkyl group, wee synthesized. Of the four drug analogues only compound 9, related to terbinafine, showed significant antifungal activity. PMID:7568314

  11. CONGENER-SPECIFIC DETECTION OF DIOXINS USING JET-REMPI. (R827927)

    EPA Science Inventory

    Although 210 chemically different polychlorinated dibenzo-p-dioxin and dibenzofuran congeners can be produced during combustion, it is currently believed that fewer than 20 are toxic enough to warrant monitoring. SRI is developing a continuous emissions monitor to study...

  12. Comparison of PBDE congeners as inducers of oxidative stress in zebrafish.

    PubMed

    Usenko, Crystal Y; Abel, Erika L; Kudela, Molly; Janise, Annie; Bruce, Erica D

    2015-05-01

    A proposed primary pathway through which polybrominated diphenyl ethers (PBDEs) disrupt normal biological functions is oxidative stress. In the present study, 4 PBDE congeners were evaluated for their potential to initiate oxidative stress in zebrafish during development: BDE 28, BDE 47, BDE 99, and BDE 100. N-acetylcysteine (NAC) was used to increase intracellular glutathione concentrations and only decreased the effects of BDE 28 at 10 ppm and 20 ppm and BDE 47 at 20 ppm. N-acetylcysteine coexposure did not alter the rates of mortality or curved body axis compared with PBDE exposure alone. The activity of glutathione-S-transferase (GST) was not altered at 24 h postfertilization (hpf), but increased following 10 ppm BDE 28 exposure at 120 hpf. Transcription of several genes associated with stress was also evaluated. At 24 hpf, cytochrome c oxidase subunit 6a (COX6a) transcription was up-regulated in embryos exposed to BDE 99, and BDE 28 exposure up-regulated the transcription of Glutathione-S-transferase-pi (GSTpi). At 24 hpf, glutamate-cysteine ligase (GCLC) was slightly down-regulated by all congeners evaluated. At 120 hpf, TNF receptor-associated protein 1 (TRAP1) and COX6A were up-regulated by all congeners, however GSTpi was down-regulated by all congeners. The results of quantitative real-time transcription polymerase chain reaction are mixed and do not strongly support a transcriptional response to oxidative stress. According to the authors' data, PBDEs do not induce oxidative stress. Oxidative stress may occur at high exposure concentrations; however, this does not appear to be a primary mechanism of action for the PBDE congeners tested. PMID:25663549

  13. A High-Speed Congenic Strategy Using First-Wave Male Germ Cells

    PubMed Central

    Ogonuki, Narumi; Inoue, Kimiko; Hirose, Michiko; Miura, Ikuo; Mochida, Keiji; Sato, Takahiro; Mise, Nathan; Mekada, Kazuyuki; Yoshiki, Atsushi; Abe, Kuniya; Kurihara, Hiroki; Wakana, Shigeharu; Ogura, Atsuo

    2009-01-01

    Background In laboratory mice and rats, congenic breeding is essential for analyzing the genes of interest on specific genetic backgrounds and for analyzing quantitative trait loci. However, in theory it takes about 3–4 years to achieve a strain carrying about 99% of the recipient genome at the tenth backcrossing (N10). Even with marker-assisted selection, the so-called ‘speed congenic strategy’, it takes more than a year at N4 or N5. Methodology/Principal Findings Here we describe a new high-speed congenic system using round spermatids retrieved from immature males (22–25 days of age). We applied the technique to three genetically modified strains of mice: transgenic (TG), knockin (KI) and N-ethyl-N-nitrosourea (ENU)-induced mutants. The donor mice had mixed genetic backgrounds of C57BL/6 (B6)∶DBA/2 or B6∶129 strains. At each generation, males used for backcrossing were selected based on polymorphic marker analysis and their round spermatids were injected into B6 strain oocytes. Backcrossing was repeated until N4 or N5. For the TG and ENU-mutant strains, the N5 generation was achieved on days 188 and 190 and the proportion of B6-homozygous loci was 100% (74 markers) and 97.7% (172/176 markers), respectively. For the KI strain, N4 was achieved on day 151, all the 86 markers being B6-homozygous as early as on day 106 at N3. The carrier males at the final generation were all fertile and propagated the modified genes. Thus, three congenic strains were established through rapid generation turnover between 41 and 44 days. Conclusions/Significance This new high-speed breeding strategy enables us to produce congenic strains within about half a year. It should provide the fastest protocol for precise definition of the phenotypic effects of genes of interest on desired genetic backgrounds. PMID:19333383

  14. PCB concentration in fish in a river system after remediation of contaminated sediment

    SciTech Connect

    Bremle, G.; Larsson, P.

    1998-11-15

    An 1991 investigation of PCB concentrations in water and fish along a river was repeated in 1996 after the completion of a remediation of PCB-containing sediment in a lake within the river system. The PCB concentrations in the lake water decreased significantly, and the concentrations in fish was halved (significantly lower) after remediation. PCB still remaining in littoral sediment was probably the cause for a recorded gradient of PCB concentrations in fish from the lake and downstream. The PCB concentrations in water and fish was lower in 1996 compared to 1991 in all locations studied. The decreased levels of PCB in fish between the years for the two upstream locations, probably results from a decline in background PCB exposure. Monitoring data from 30 years back, recorded in a south Swedish lake, has shown a 5% decline per year in the PCB concentration in pike. The data on PCB concentration in fish from the two upstream locations were recalculated on the basis of this yearly decline and resulted in concentrations close to those measured in 1996. The results indicated, that changes in background exposure must be taken into account when evaluating the success of remedial actions measures carried out over several years.

  15. Differences in Energy Expenditures and Growth Dilution Explain Higher PCB Concentrations in Male Summer Flounder.

    PubMed

    Madenjian, Charles P; Jensen, Olaf P; Rediske, Richard R; O'Keefe, James P; Vastano, Anthony R; Pothoven, Steven A

    2016-01-01

    Comparison of polychlorinated biphenyl (PCB) concentrations between the sexes of mature fish may reveal important behavioral and physiological differences between the sexes. We determined whole-fish PCB concentrations in 23 female summer flounder Paralichthys dentatus and 27 male summer flounder from New Jersey coastal waters. To investigate the potential for differences in diet or habitat utilization between the sexes, carbon and nitrogen stable isotope ratios were also determined. In 5 of the 23 female summer flounder, PCB concentrations in the somatic tissue and ovaries were determined. In addition, we used bioenergetics modeling to assess the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 87 and 124 ng/g, respectively; thus males were 43% higher in PCB concentration compared with females. Carbon and nitrogen stable isotope ratios did not significantly differ between the sexes, suggesting that diet composition and habitat utilization did not vary between the sexes. Based on PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 0.6%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain the higher PCB concentrations observed in males. Bioenergetics modeling results indicated that the growth dilution effect could account for males being 19% higher in PCB concentration compared with females. Thus, the bulk of the observed difference in PCB concentrations between the sexes was not explained by growth dilution. We concluded that a higher rate of energy expenditure in males, stemming from greater activity and a greater resting metabolic rate, was most likely the primary driver for t