High Concentrations Of Polychlorinated Biphenyls Research Articles

Perinatal polychlorinated biphenyls and polychlorinated dibenzofurans exposure are associated with DNA methylation changes lasting to early adulthood: Findings from Yucheng second generation

Epigenome-wide DNA methylation has not been studied in men perinatally exposed to PCBs and dioxins. Therefore, we examined whether perinatal exposure to polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs) induces sustained methylation changes lasting to early adulthood. We used the Illumina HumanMethylation450 BeadChip to assess DNA methylation in whole blood among Yucheng second generation (people perinatal exposed to high PCBs and PCDFs) compared with referents. Thirty male offspring from the Yucheng cohort were randomly selected and matched with 30 male offspring from the Yucheng’ neighborhood referents with similar backgrounds. Methylation differences between the Yucheng second generation and non-exposed referents were identified using a P value < 1.06 × 10−7. Differential DNA methylation with epigenome-wide statistical significance was observed for 20 CpGs mapped to 11 genes, and 19 CpGs were correlated with gestational levels of PCBs or PCDF toxic equivalency (PCDF-TEQ) with the same direction of effect. Among the 11 genes, AHRR and CYP1A1 are involved in the aryl hydrocarbon receptor signaling pathway known to mediate dioxin toxicity. MYO1G, FRMD4A, ARL4C, OLFM1, and WWC3 were previously reported to be related to carcinogenesis. This is the first study examining genome-wide DNA methylation among people perinatally exposed to high concentrations of PCBs and PCDFs. We observed novel differential methylation of several genes, indicating that modifications of DNA methylation associated with perinatal PCB and PCDF exposure may persist in exposed offspring for more than 20 years. Furthermore, involvement of several carcinogesis-related genes suggested a potential in utero epigenetic mechanisms.

Polycyclic aromatic hydrocarbons and polychlorinated biphenyls in soils and atmosphere of Western Canadian mountains: The role of source proximity, precipitation, forest cover and mountain cold-trapping

Abstract Soil was sampled and XAD-2 based passive air samplers were deployed for one year at several locations on four mountains and a mountain pass in British Columbia (BC), Canada. The mountains, ranging between ca. 1100–1500 m in altitude, varied in their proximity to likely sources of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). Considered mountain-by-mountain, proximity to sources determines the concentrations of PCBs: Grouse Mountain, immediately to the North of Vancouver, had the highest PCB concentrations in both atmospheric gas phase and soil, while three other mountains in southern BC had levels approximately a factor of three lower. PCB concentrations along the Chilkoot Trail in remote Northern BC were more than an order of magnitude lower. While Grouse Mountain also had the highest PAH concentrations, gas phase concentrations of PAHs elsewhere were only slightly lower and varied little between the different mountains. Soil concentrations of PAHs were highly elevated on urban Grouse Mountain and lowest on Blue Grouse Mountain, which stands out by having the driest climate. On a site-by-site basis, PCB concentrations in the atmospheric gas phase decreased with increasing elevation but show indication of upslope enrichment in the soils of three of the mountains. These include the most urban mountain and two rural mountains, which have more precipitation and forest coverage than the remaining two mountains. There was no difference between congeners in the extent of upslope enrichment, indicating that the temperature gradient along the mountains was not sufficiently large to cause fractionation. Atmospheric gas phase and soil concentrations of PAHs on a mountain decrease with distance from likely sources. Although sources of PAHs are too widespread to observe any trends of mountain cold-trapping, PCBs are clearly experiencing cold-trapping in Western Canadian mountains.

Hepatic metabolite profiling of polychlorinated biphenyl (PCB)-resistant and sensitive populations of Atlantic killifish (Fundulus heteroclitus)

Atlantic killifish inhabiting polluted sites along the east coast of the U.S. have evolved resistance to toxic effects of contaminants. One such contaminated site is the Acushnet River estuary, near New Bedford Harbor (NBH), Massachusetts, which is characterized by very high PCB concentrations in the sediments and in the tissues of resident killifish. Though killifish at this site appear to be thriving, the metabolic costs of survival in a highly contaminated environment are not well understood. In this study we compared the hepatic metabolite profiles of resistant (NBH) and sensitive populations (Scorton Creek (SC), Sandwich, MA) using a targeted metabolomics approach in which polar metabolites were extracted from adult fish livers and quantified. Our results revealed differences in the levels of several metabolites between fish from the two sites. The majority of these metabolites are associated with one-carbon metabolism, an important pathway that supports multiple physiological processes including DNA and protein methylation, nucleic acid biosynthesis and amino acid metabolism. We measured the gene expression of DNA methylation (DNA methyltransferase 1, dnmt1) and demethylation genes (Ten-Eleven Translocation (TET) genes) in the two populations, and observed lower levels of dnmt1 and higher levels of TET gene expression in the NBH livers, suggesting possible differences in DNA methylation profiles. Consistent with this, the two populations differed significantly in the levels of 5-methylcytosine and 5-hydroxymethylcytosine nucleotides. Overall, our results suggest that the unique hepatic metabolite signatures observed in NBH and SC reflect the adaptive mechanisms for survival in their respective habitats.

Quantitative analyses of selected polychlorinated biphenyl (PCB) congeners in water, soil, and sediment during winter and spring seasons from Msunduzi River, South Africa.

The lack of information and the need for knowledge on the organic pollutants within the area of KwaZulu-Natal together with the global problem of water supply have prompted our investigation into the analyses of eight polychlorinated biphenyl (PCB) congeners in the Msunduzi River of KwaZulu-Natal, South Africa. Soil, sediment, and water samples were collected at ten different sites along the river during winter and spring seasons. Soil and sediment samples were extracted using ultra sonication with dichloromethane while water samples were liquid-liquid extracted using dichloromethane. All sample extracts were cleaned-up using a multi-layer silica gel column and analyzed with gas chromatography-mass spectrometry. Quality assurance measures were also determined. The percentage recoveries for water were 53-128 for all the PCBs analyzed, while sediment recoveries ranged between 69 and 105%. The highest total concentrations of the PCBs in sediment were 214.21-610.45ng/g dw at the Du Toit sampling site and 30.86-444.43ng/g dw basis at the wastewater treatment inlet for winter and spring, respectively. Soil PCB concentrations were 76.53-397.75ng/g dw at the Msunduzi Town sampling site and 20.84-443.49ng/g (dry weight) at the Du Toit sampling site for winter and spring, respectively. In addition, high PCB concentrations were found in effluent of the wastewater treatment inlet compared to other sampling sites, which ranged between 0.68-22.37 and 2.53-35.69ng/mL for winter and spring seasons, respectively. In all the sampling sites selected for this study, Du Toit afforded the highest PCB concentration levels and the lowest was after chlorination at the Darvill wastewater treatment plant. The results presented are new and it is the first study of organic pollutants such as PCBs that has been carried out on this river.

PCB—still a problem

Persistent Chemicals![Figure][1] Killer whales are still being damaged by PCBs in the environment. CREDIT: PHOTO: AUDUN RIKARDSEN Until they were recognized as highly toxic and carcinogenic, polychlorinated biphenyls (PCBs) were once used widely. Their production was banned in the United States in 1978, though they are still produced globally and persist in the environment. Persistent organic compounds, like PCBs, magnify across trophic levels, and thus apex predators are particularly susceptible to their ill effects. Desforges et al. looked at the continuing impact of PCBs on one of the largest marine predators, the killer whale. Using globally available data, the authors found high concentrations of PCBs within killer whale tissues. These are likely to precipitate declines across killer whale populations, particularly those that feed at high trophic levels and are the closest to industrialized areas. Science , this issue p. [1373][2] [1]: pending:yes [2]: /lookup/doi/10.1126/science.aat1953

Predicting global killer whale population collapse from PCB pollution.

Killer whales (Orcinus orca) are among the most highly polychlorinated biphenyl (PCB)-contaminated mammals in the world, raising concern about the health consequences of current PCB exposures. Using an individual-based model framework and globally available data on PCB concentrations in killer whale tissues, we show that PCB-mediated effects on reproduction and immune function threaten the long-term viability of >50% of the world's killer whale populations. PCB-mediated effects over the coming 100 years predicted that killer whale populations near industrialized regions, and those feeding at high trophic levels regardless of location, are at high risk of population collapse. Despite a near-global ban of PCBs more than 30 years ago, the world's killer whales illustrate the troubling persistence of this chemical class.

A Bayesian assessment of polychlorinated biphenyl contamination of fish communities in the Laurentian Great Lakes

Polychlorinated biphenyl (PCB) contamination has historically posed constraints on the recreational and commercial fishing industry in the Great Lakes. Empirical evidence suggests that PCB contamination represents a greater health risk from fish consumption than other legacy contaminants. The present study attempts a rigorous assessment of the spatio-temporal PCB trends in multiple species across the Canadian waters of the Great Lakes. We applied a Bayesian modelling framework, whereby we initially used dynamic linear models to delineate PCB levels and rates of change, while accounting for the role of fish length and lipid content as covariates. We then implemented Bayesian hierarchical modelling to evaluate the temporal PCB trends during the dreissenid pre- and post-invasion periods, as well as the variability among and within the water bodies of the Great Lakes system. Our analysis indicates that Lake Ontario is characterized by the highest PCB levels among nearly all of the fish species examined. Historically contaminated local areas, designated as Areas of Concern, and embayments receiving riverine inputs displayed higher concentrations within each of the water bodies examined. The general temporal trend across the Great Lakes was that the high PCB concentrations during the early 1970s followed a declining trajectory throughout the late 1980s/early 1990s, likely as a result of the reductions in industrial emissions and other management actions. Nonetheless, after the late 1990s/early 2000s, our analysis provided evidence of a decline in the rate at which PCB concentrations in fish were dropping, accompanied by a gradual establishment of species-specific, steady-state concentrations, around which there is considerable year-to-year variability. The overall trends indicate that reduced contaminant emissions have brought about distinct beneficial changes in fish PCB concentrations, but past historical contamination along with other external or internal stressors (e.g., invasive species, climate change) continue to modulate the current levels, thereby posing potential risks to humans through fish consumption.

Enhanced biochars can match activated carbon performance in sediments with high native bioavailability and low final porewater PCB concentrations

A bench scale study was conducted to evaluate the effectiveness of in situ amendments to reduce the bioavailability of pollutants in sediments from a site impacted with polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and cadmium. The amendments tested included fine and coarse coal-based activated carbons (AC), an enhanced pinewood derived biochar (EPB), organoclay, and coke dosed at 5% of sediment dry weight. Strong reductions in total PCB porewater concentrations were observed in sediments amended with the fine AC (94.9–99.5%) and EPB (99.6–99.8%). More modest reductions were observed for the coarse AC, organoclay, and coke. Strong reductions in porewater PCB concentrations were reflected in reductions in total PCB bioaccumulation in fresh water oligochaetes for both the fine AC (91.9–96.0%) and EPB (96.1–96.3%). Total PAH porewater concentrations were also greatly reduced by the fine AC (>96.1%) and EPB (>97.8%) treatments. EPB matched or slightly outperformed the fine AC throughout the study, despite sorption data indicating a much stronger affinity of PCBs for the fine AC. Modeling EPB and fine AC effectiveness on other sediments confirmed the high effectiveness of the EPB was due to the very low final porewater concentrations and differences in the native bioavailability between sediments. However, low bulk density and poor settling characteristics make biochars difficult to apply in an aquatic setting. Neither the EPB nor the fine AC amendments were able to significantly reduce Cd bioavailability.

Characterization of polychlorinated biphenyls in surface sediments of the North End Lake, Port Elizabeth, South Africa

The distribution and concentrations of 6 indicator polychlorinated biphenyl (PCB) congeners, nos. 28, 52, 101, 138, 153 and 180, were determined in surface sediments from the North End Lake in Port Elizabeth, South Africa. Forty-two surficial sediment samples were collected from different locations covering the region that receives the majority of the industrial waste, urban effluents and runoff and thus expected to be contaminated with different degrees of contamination. The analysis was achieved by gas chromatography-mass spectrometry (GC/MS) using the internal standard method. The total PCB concentrations in the samples ranged from 1.60 to 3.06 ng·g -1 dry weight (dw). The concentrations of congener profiles showed significant differences. Generally, the highest PCB concentrations were associated with high organic matter contents and small grain size. The highly chlorinated PCBs dominated with regards to the levels in sediments. PCB 138 was the major contributor to the total PCBs and was detected at 100% of sites. This study provided a snapshot of the PCB contamination status in the North End Lake sediments, and allowed for a comparison between the investigated system and other systems worldwide. Keywords : PCBs, sediments, organic matter, particle size, North End Lake

The effect of follicullar fluid pesticides and polychlorinated biphenyls concentrations on intracytoplasmic sperm injection (ICSI) embryological and clinical outcome

ObjectivesThe present study evaluated the correlation between the concentrations of polychlorinated biphenyls (PCBs) and pesticides in the follicular fluid (FF) obtained during intracytoplasmic sperm injection (ICSI) with the ovarian response, endometrial thickness, and embryological and clinical outcomes. DesignCross-sectional observational study. Materials and methodsWomen aged 20 to 38 years (300 infertile couples) presenting to a university-affiliated fertility center were approached to participate in the study. Only 150 couples that underwent ICSI for male factor infertility agreed to participate, and 94 of them had retrieved enough FF samples suitable for laboratory testing. The FF sample was obtained, centrifuged, and stored in liquid nitrogen. Two organochlorine pesticides (OCPs), Lindane and DDT;three organophosphates (OPs);chlorpyrifos;Diazinon; malathion; one Chloroacetanilide (Pretilachlor);two pyrethroids(Bioallethrin and β-cyfluthrin); and the concentrations of four PCBs, 28, 52, 138, 180, were estimated in the obtained FF samples by using gas chromatography/mass spectrometry. SPSS statistical analysis program (version 17) was used for analysis. Multiple regression analysis was used to correlate the PCBs and pesticides with ICSI outcomes. ResultsThere were significant negative correlations between FF concentrations of the eight examined pesticides and the four PCBs on the endometrial thickness. However, Pretilachlor, chlorpyrifos, β-cyfluthrin, and Diazinon were the only toxic agents that negatively correlated with the number of the oocytes retrieved. Fertilization and early embryo cleavage rates were negatively correlated with Pretilachlor and β-cyfluthrin. Moreover, high concentrations of Lindane,DDT, Diazinon,and chlorpyrifos were significantly associated lower implantation rate. PCB 28 and 180 concentration in the FF was associated with a lower number of retrieved oocytes and fertilization rate, respectively. The number of implanted embryos was negatively correlated with PCB 52 FF concentration. However, the clinical pregnancy rate did not reach the level of significance. ConclusionHigher concentrations of any studied PCBs and pesticides are associated with thinner endometrial thickness. The higher the level of Pretilachlor, β-cyfluthrin, PCB 28 and 180, the lower the retrieval, fertilization, and embryo cleavage rates. High PCB and pesticide concentrations in the FF adversely affected embryological ICSI outcomes. However, more data are needed to evaluate their effect on the clinical outcome.

Updated Polychlorinated Biphenyl Mass Budget for Lake Michigan.

This study revisits and updates the Lake Michigan Mass Balance Project (LMMBP) for polychlorinated biphenyls (PCBs) that was conducted in 1994-1995. This work uses recent concentrations of PCBs in tributary and open lake water, air, and sediment to calculate an updated mass budget. Five of the 11 LMMBP tributaries were revisited in 2015. In these five tributaries, the geometric mean concentrations of ∑PCBs (sum of 85 congeners) ranged from 1.52 to 22.4 ng L-1. The highest concentrations of PCBs were generally found in the Lower Fox River and in the Indiana Harbor and Ship Canal. The input flows of ∑PCBs from wet deposition, dry deposition, tributary loading, and air to water exchange, and the output flows due to sediment burial, volatilization from water to air, and transport to Lake Huron and through the Chicago Diversion were calculated, as well as flows related to the internal processes of settling, resuspension, and sediment-water diffusion. The net transfer of ∑PCBs is 1240 ± 531 kg yr-1 out of the lake. This net transfer is 46% lower than that estimated in 1994-1995. PCB concentrations in most matrices in the lake are decreasing, which drove the decline of all the individual input and output flows. Atmospheric deposition has become negligible, while volatilization from the water surface is still a major route of loss, releasing PCBs from the lake into the air. Large masses of PCBs remain in the water column and surface sediments and are likely to contribute to the future efflux of PCBs from the lake to the air.

Persistent threats need persistent counteraction: Responding to PCB pollution in marine mammals

Polychlorinated biphenyls (PCBs) are a type of persistent organic pollutant (POP) that continues to pose a significant environmental threat to humans and wildlife. Recent scientific evidence shows that very high PCB concentrations are still major causes of contemporary declines in European cetacean populations, and potentially other marine apex predators globally. Currently, controls on PCBs are insufficient, on their own, to fully protect human health or to conserve wildlife. Although the Stockholm Convention provides a global framework to address PCBs, there appears to be a systemic shortfall of many parties of the Convention to provide sufficient prioritisation and resources for effective implementation. A 2015 United Nations Environment Programme assessment estimates that the vast majority of PCB-contaminated equipment and materials, around 14 million tonnes, still requires elimination. At present rates of PCB elimination or mitigation, many countries, including some European countries, will not achieve the 2025 and 2028 targets of the Stockholm Convention. It is imperative that the Conference of the Parties for the Stockholm Convention conclude article 17 negotiations on a compliance mechanism for the Convention as soon as possible. To help mobilise global efforts towards eliminating the threat from PCBs, an enforceable, effective and robust compliance mechanism should be established, along with capacity building support for developing countries. In Europe, renewed action is needed to reduce PCB contamination, in order to prevent some killer whale (Orcinus orca) and other dolphin populations from continuing to slowly decline, potentially towards extinction.

Polychlorinated biphenyls in the surrounding of an e-waste recycling facility in North-Rhine Westphalia: Levels in plants and dusts, spatial distribution, homologue pattern and source identification using the combination of plants and wind direction data

During this study the occurrence of polychlorinated biphenyls (PCBs) in the surrounding of an e-waste recycling facility in North-Rhine Westphalia was analysed. PCB levels were analysed in curly kale, spruce needles, street dusts and dusts. Conspicuously high PCB concentrations in curly kale and spruce needles were found directly northwards of the industrial premises. Furthermore a concentration gradient originating from the industrial premises to the residential areas in direction southwest to northeast was evident. Homologue patterns of highly PCB contaminated dusts and street dusts were comparable to the homologue patterns of PCB in curly kale and spruce needles. This corroborates the suspicion that the activities at the e-waste recycling facility were responsible for the elevated PCB levels in curly kale and spruce needles. The utilization of multiple linear regression of wind direction data and analysed PCB concentrations in spruce needles proved that the e-waste recycling facility caused the PCB emissions to the surrounding. Additionally, this evaluation enabled the calculation of source specific accumulation constants for certain parts of the facility. Consequently the different facility parts contribute with different impacts to the PCB levels in bioindicators.

Release of Airborne Polychlorinated Biphenyls from New Bedford Harbor Results in Elevated Concentrations in the Surrounding Air.

Qualitatively and quantitatively, we have demonstrated that airborne polychlorinated biphenyl (PCB) concentrations in the air surrounding New Bedford Harbor (NBH) are caused by its water PCB emissions. We measured airborne PCBs at 18 homes and businesses near NBH in 2015, with values ranging from 0.4 to 38 ng m–3, with a very strong Aroclor 1242/1016 signal that is most pronounced closest to the harbor and reproducible over three sampling rounds. Using U.S. Environmental Protection Agency (U.S. EPA) water PCB data from 2015 and local meteorology, we predicted gas-phase fluxes of PCBs from 160 to 1200 μg m–2 day–1. Fluxes were used as emissions for AERMOD, a widely applied U.S. EPA atmospheric dispersion model, to predict airborne PCB concentrations. The AERMOD predictions were within a factor of 2 of the field measurements. PCB emission from NBH (110 kg year–1, average 2015) is the largest reported source of airborne PCBs from natural waters in North America, and the source of high ambient air PCB concentrations in locations close to NBH. It is likely that NBH has been an important source of airborne PCBs since it was contaminated with Aroclors more than 60 years ago.

Spatial distribution and bioaccumulation of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in snails (Bellamya aeruginosa) and sediments from Taihu Lake area, China

Taihu Lake area is one of the densest metropolitan areas in the world including diverse industrial activity. In the present study, the snail (Bellamya aeruginosa) and sediment were collected from the Taihu Lake area to investigate the contamination status, congener pattern, spatial distribution, and bioaccumulation effect of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). The samples underwent liquid extraction, lipid removal by sulfuric acid, and acidic silica gel column, and subsequently analyzed by gas chromatography-electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS). Concentration of ∑22PCBs ranged between 90 and 680 ng g−1 lipid weight in the snails and between 0.018 and 0.82 ng g−1 dry weight in the sediments. Concentration of ∑24PBDEs varied from 25 to 200 ng g−1 lipid weight in the snails and from 0.62 to 67 ng g−1 dry weight in the sediments. The levels of PCBs and PBDEs observed were in the medium to low range compared with other studies in the world. CB-153 was the predominant PCB congener in both snails and sediments whereas BDE-209 showed a low bioavailability in the snails, even if it contributed up to 70% of ∑24PBDEs in the sediments. The spatial distribution showed that the highest concentration of PCBs and PBDEs were detected in samples from Zhushan Lake. East Taihu Lake and Dianshan Lake showed lower concentration of PCBs and PBDEs than the other sampling sites. Biota-sediment accumulation was found between snails and sediments of most of PCB and PBDE congeners except for the highly brominated BDEs (i.e., BDE-209). Therefore, sediment is suggested to be an appropriate matrix to monitor BDE-209 while aquatic species such as the snail could be good for monitoring of PCBs and lower brominated BDE congeners. No significant correlation (Spearman correlation test, two-tailed) of CB-153 (r = 0.54, p = 0.27) or BDE-47 (r = 0.60, p = 0.21) was found between snails and sediments.

Factors influencing the atmospheric concentrations of PCBs at an abandoned e-waste recycling site in South China

The diurnal atmospheric concentrations of polychlorinated biphenyls (PCBs) were investigated at an abandoned e-waste recycling site in South China during winter and summer. Total PCB concentrations during winter and summer were 27.6–212 and 368–1704pg/m3 in the particulate phase and 270–697 and 3000–15,500pg/m3 in the gaseous phase, respectively. Both gaseous and particulate PCB concentrations and compositions exhibited significant difference between winter and summer samples, but no diurnal variations during the measurement period. The correlation analysis between PCB concentrations and meteorological conditions, including atmospheric temperature, humidity, and mixing layer height, suggested that the seasonal variability of atmospheric PCB concentrations was strongly temperature-dependent, while the diurnal variability was probably source-dependent. The temperature-driven variations can also be proved by the significant linear correlation between ln P and 1/T in the Clausius-Clapeyron plot. Although government has implemented controls to reduce e-waste pollution, both the relatively high concentrations of PCBs and the diurnal variation in the air suggested that emissions from occasional e-waste recycling activities may still exist in this recycling area. These results underline the importance of continuing e-waste recycling site management long after abandonment.

Integrating Monitoring and Genetic Methods To Infer Historical Risks of PCBs and DDE to Common and Roseate Terns Nesting Near the New Bedford Harbor Superfund Site (Massachusetts, USA).

Common and roseate terns are migratory piscivorous seabirds with major breeding colonies within feeding range of the polychlorinated biphenyl (PCB)-contaminated New Bedford Harbor (NBH, MA, USA) Superfund site. Our longitudinal study shows that before PCB discharges into NBH ceased (late 1970s), tern eggs had very high but variable PCB concentrations. However, egg concentrations of PCBs as well as DDE (1,1-bis(p-chlorophenyl)-2,2-dichloroethene), the degradation product of the ubiquitous global contaminant DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl) ethane), have since declined. Rate constants for temporal decline of PCB congeners in tern eggs varied inversely with log10KOW (n-octanol-water partition coefficient), shifting egg congener patterns away from those characterizing NBH sediment. To estimate the toxic effects on tern eggs of PCB dioxin-like congener (DLC) exposures, we extrapolated published laboratory data on common terns to roseate terns by characterizing genetic and functional similarities in species aryl hydrocarbon receptors (AHRs), which mediate DLC sensitivity. Our assessment of contaminant risks suggests that terns breeding near NBH were exposed historically to toxic levels of PCBs and DDE; however, acute effects on tern egg development have become less likely since the 1970s. Our approach demonstrates how comparative genetics at target loci can effectively increase the range of inference for chemical risk assessments from tested to untested and untestable species.

Polychlorinated biphenyls in agricultural soils from the Yangtze River Delta of China: Regional contamination characteristics, combined ecological effects and human health risks

The current contamination status of polychlorinated biphenyls (PCBs) was studied in the agricultural soils of the Yangtze River Delta (YRD), one of the largest economic zones in China. The concentrations of PCBs ranged from <0.1 to 130 ng/g dry weight. Higher concentrations of PCBs were observed in the 0–30 cm surface layers relative to the subsurface soils. A distinct spatial distribution was observed with a declining concentration gradient from the northwest to the southeast of the region. The composition of PCBs in the soils was consistent with the Chinese commercial PCB mixtures, but different from the compositions in global background soil. Local sources including large-scale use and disposal of PCB-containing products were the main potential sources to soil. The ecological effects and human health risks associated with combined persistent organic pollutants, including PCBs, organochlorine pesticides (OCPs), phthalate esters (PAEs) and polybrominated diphenyl ethers (PBDEs), were further estimated. The four toxic organic compounds and seven physicochemical parameters together could only explain 12.7% of the variation in microbial community composition, suggesting the soil ecosystem function was not strongly influenced by the combined pollution at low concentrations. However, the potential health risks to residents via multiple pathways were notably higher for PCBs than other chemicals. The potential risks were mainly derived from PCB-126, 81, and 169.

Abstract 3456: Polychlorinated biphenyls and relative telomere length in the Anniston Community Health Survey: A cross-sectional study

Abstract Background: Polychlorinated biphenyls (PCBs) exposure is associated with increased risk of melanoma and non-Hodgkin lymphoma in some, but not all, epidemiologic studies. Although the carcinogenic mechanisms of specific PCB congeners remain to be fully explained, PCBs have been demonstrated to induce oxidative stress and inflammation and therefore may have deleterious impacts on telomere length. We investigated the association between serum concentrations of PCBs and telomere length in a highly exposed population. Methods: The Anniston Community Health Survey (ACHS) is a cross-sectional study of 766 residents of Anniston, Alabama conducted between 2005 and 2007. We measured relative telomere length (RTL) with telomere/single copy gene ratio, in DNA extracted from peripheral blood samples in a subset of 57 African-American and 46 white participants, using monochrome multiplex quantitative polymerase chain reaction. We used multiple linear regression to estimate the association between 27 individual PCB congeners, and sum PCBs, adjusting for age, plate, and total lipids. All analyses were stratified by race. PCBs and RTL were log-transformed. Results: ACHS participants had high serum concentrations of PCBs (mean sum PCBs among African-Americans = 14,687.69 ppt whole weight, SD = 23,515.46; mean sum PCBs white participants 6,088.32 ppt whole weight, SD = 8,750.57). RTL did not differ by race (mean RTL African-Americans = 0.94 SD = 0.08; mean RTL whites = 0.94, SD = 0.09). Among African-American participants, sum serum PCBs was not associated with RTL (0.70% per 100 ppt; 95% confidence interval = -9.43, 19.70). However, PCB 167 was weakly associated with higher RTL (2.35%, 95%CI = -8.56, 14.55), while PCB 157 was associated with shorter RTL (-4.36%; 95%CI = -15.63, 8.40). Among white participants, a 100 ppt increase in sum serum PCBs was associated with a 10.20% increase in RTL (95% CI = -7.10, 30.72). PCB 138, in particular, was associated with increased RTL among white participants (16.29%; 95% CI = 1.34, 33.46). Conversely, PCB 189 was associated with shorter RTL among white participants (-10.48%; 95%CI = -29.82, 14.19). Conclusions: We did not observe consistent associations between serum concentrations of PCBs and RTL, suggesting that the association may vary by race and be congener specific. Our results are necessarily preliminary and are limited by the small number of participants. Additional measurements of RTL among ACHS participants are on-going. Citation Format: Catherine Callahan, Marian Pavuk, Xuefeng Ren, James R. Olson, Matthew R. Bonner. Polychlorinated biphenyls and relative telomere length in the Anniston Community Health Survey: A cross-sectional study. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3456.

Polychlorinated biphenyls (PCBs) in adult and juvenile mallards (Anas platyrhynchos) from the Hudson River, New York, USA

The Hudson River, NY, USA is contaminated for over 300 km with polychlorinated biphenyls (PCBs) released from two General Electric (GE) capacitor plants. We collected adult and juvenile mallards (Anas platyrhynchos) from four different areas of the river; an area upstream of the GE plants (n = 38), two areas directly downstream of the GE plants (n = 41, n = 38), and an area more than 100 km downstream in the freshwater tidal river (n = 20). Collections occurred during July and August (2008) when ducks were flightless to ensure ducks were “resident” and exposures were local. Fat and muscle tissue were analyzed for PCBs. PCBs were detected in all samples, and mallards below the GE plant sites on the Hudson River had orders of magnitude higher concentrations of PCBs than those above the plants. Juvenile mallards from areas directly downstream of the GE plant sites tended to have higher PCB concentrations in fat than adults. The patterns of PCB congeners and homolog groups varied across the study areas, with areas directly downstream of the GE plants dominated by tetra-chloro biphenyls whereas samples from upstream and the freshwater tidal river tended towards higher chlorinated congeners. Congener patterns between male and female and juvenile and adult mallards were generally similar within study areas, with the exception of one area downstream of the GE plants where adult birds exhibited different patterns than juveniles. Evidence of PCBs from the GE plant sites was detected in the tidal Hudson River, more than 100 km downstream of the plant sites. More than 90% of the ducks collected in areas downstream of the GE plants but above the tidally influenced river exceed the USFDA tolerance level for PCBs in poultry, which should be a concern for consumers of waterfowl taken in proximity to the upper Hudson River.