Total Polychlorinated Biphenyls Concentrations Research Articles

Determination of Polychlorinated Biphenyls in Aegean Fish and Seafood

ABSTRACTNon-dioxin-like polychlorinated biphenyls (PCBs) are toxic, may cause neurological and reproductive disorders, and are carcinogenic. Human exposure to PCBs is mainly from food. Six non-dioxin-like PCBs congeners have been selected by the European Food Safety Authority as indicator PCBs. In previous studies on PCBs in food, the highest concentrations were observed in fish and fish products. The concentrations of non-dioxin-like PCBs were determined in ten species of fish and shellfish from the Aegean Sea. The concentrations of mono-ortho PCBs were also determined. Analyses were conducted in raw, fried, and grilled fish. Total indicator PCB and total mono-ortho PCB concentrations were above the detection limit in all samples with values from 0.21 to 32.4 ng g−1 wet weight and 0.001 to 0.217 toxic equivalent pg g−1 wet weight, respectively. The effects of cooking on PCB concentrations and the dietary intake were evaluated.

Measuring the bioavailability of polychlorinated biphenyls to earthworms in soil enriched with biochar or activated carbon using triolein-embedded cellulose acetate membrane

Polychlorinated biphenyls (PCBs) are persistent soil contaminants that resist biodegradation and present serious risks to living organisms. The presence of biochar in soils can lower the availability of PCBs to biota. In this study, the effect of biochar enrichment in soils on bioaccumulation of PCBs was investigated. We applied two types of biochar including pine needle biochar (PC) and wheat straw biochar (WC), and an activated carbon (AC) to soil (2 % w/w) and employed two alternative methods to quantified rates of bioaccumulation: a living bioassay (using earthworm, Eisenia fetida, as a model organism) and a triolein-embedded cellulose acetate membrane (TECAM). Our results show that the application of biochar or AC greatly reduced the uptake of PCBs (particularly less-chlorinated PCBs) by earthworms (the reduction in total PCBs concentration was up to 40.0 and 49.0 % for PC and WC treatments, while 71.6 % for AC application). We found that the bioaccumulation factors (BAFs) for PCBs in the earthworms in biochar/AC-enriched soils were strongly correlated with O:C ratio of the biochar/AC (R 2 = 0.998, p < 0.05). We observed that BAFs increased at log K OW below 6.3 and decreased at log K OW values greater than 6.3. We demonstrated that the concentration of PCBs in TECAM membranes were positively correlated with the concentration of PCBs earthworms in soil. TECAM offers an efficient and cost-effective method for predicting the bioavailability of PCBs in field-contaminated soils undergoing sorbent-based remediation.

Persistent organic pollutants carried on plastic resin pellets from two beaches in China

Microplastics provide a mechanism for the long-range transport of hydrophobic chemical contaminants to remote coastal and marine locations. In this study, plastic resin pellets were collected from Zhengmingsi Beach and Dongshan Beach in China. The collected pellets were analyzed for PAHs, PCBs, HCHs, DDTs, chlordane, heptachlor, endosulfan, aldrin, dieldrin and endrin. The total concentration of PCBs ranged from 34.7–213.7ngg−1 and from 21.5–323.2ngg−1 in plastic resin pellets for Zhengmingsi Beach and Dongshan Beach respectively. The highest concentrations of PCBs were observed for congeners 44, 110, 138, 155 and 200. The total concentration of PAHs ranged from 136.3–1586.9ngg−1 and from 397.6–2384.2ngg−1 in the plastic pellets, whereas DDTs concentration ranged from 1.2–101.5ngg−1 and from 1.5–127.0ngg−1 for the two beaches. The elevated concentrations of pollutants appear to be related to extensive industrial development, agricultural activity and the use of coal in the area.

Distribution of polychlorinated biphenyl residues in several tissues of fish from the North End Lake, Port Elizabeth, South Africa

The concentrations and distribution of 6 PCB indicator congeners (IUPAC nos. 28, 52, 101, 138, 153, and 180) were measured in 236 organ samples of fish ( Cyprinus carpio and Oreochromis mossambicus ) from the North End Lake in Port Elizabeth, South Africa. Polychlorinated biphenyls (PCBs) were extracted from the fish muscles, gills, gonads and livers using USEPA method 8082, followed by a clean-up using concentrated sulphuric acid and florisil column chromatography. Analysis was achieved by gas chromatography–mass spectrometry (GC/MS) using the internal standard method. The concentrations of total PCBs in the liver, gonads, gills and muscle were 95.69, 57.49, 44.63, 34.14 ng∙g -1 lipid weight (lw) in C. carpio and 119.73, 59.21, 49.78, 34.63 ng∙g -1 (lw) in O. mossambicus , respectively. These values were relatively low compared to those reported in the literature. PCB levels were predictably highest in the lipid-rich livers. Individual congeners were not distributed homogeneously within the investigated organs. PCBs 153 and 138 were present at higher concentrations than other PCB congeners for both species. PCB contaminants in fish act as indicators of pollution in aquatic ecosystems and are a potential threat to human health when consumed. Keywords : PCBs, tissues, fish, GC/MS, biomagnification, North End Lake

Effects of in utero exposure to polychlorinated biphenyls, methylmercury, and polyunsaturated fatty acids on birth size

The adverse effects of in utero exposure to polychlorinated biphenyls (PCBs) or methylmercury (MeHg), and the beneficial effects of nutrients from maternal fish intake might have opposing influences on fetal growth. In this study, we assessed the effects of in utero exposure to PCBs and MeHg on birth size in the Japanese population, which is known to have a high frequency of fish consumption. The concentrations of PCBs and polyunsaturated fatty acids in maternal blood, and the total mercury in hair (as a biomarker of MeHg exposure) were measured during pregnancy and at delivery. Maternal intakes of fish (subtypes: fatty and lean) and shellfishes were calculated from a food frequency questionnaire administered at delivery. Newborn anthropometric measurement data were obtained from birth records. The associations between chemical exposures and birth size were analyzed by using multiple regression analysis with adjustment for confounding factors among 367 mother–newborn pairs. The birth weight was 3073±37g (mean±SD). The incidence of babies small for gestational age (SGA) by weight was 4.9%. The median concentrations of total PCBs and hair mercury were 108ng/g lipid and 1.41μg/g, respectively. There was no overall association between mercury concentrations and birth weight, birth length, chest circumference, and head circumference. We observed that the risk of SGA by weight decreased with increasing mercury concentration in regression analyses with adjustment for polyunsaturated fatty acids. Our results suggest that the beneficial effect of essential nutrition may mask the adverse effects of MeHg on birth size. The concentrations of PCBs had no association with birth size.

Divergent PCB organohalide-respiring consortia enriched from the efflux channel of a former Delor manufacturer in Eastern Europe

Polychlorinated biphenyl (PCB) organohalide-respiring communities from the efflux channel of a former Delor manufacturer in Eastern Slovakia were assessed using metagenomic, statistical and cultivation-adapted approaches. Multivariate analysis of environmental factors together with terminal restriction fragment length polymorphisms of the bacterial communities in the primary sediments revealed both temporal and spatial heterogeneity in the distribution of microbial populations, which reflects the dynamic pattern of contamination and altered conditions for biodegradation activity along the channel. Anaerobic microcosms were developed from eight sediments sampled along the channel, where high concentrations of PCBs – from 6.6 to 136mg/kg dry weight, were measured. PCB dehalorespiring activity, congruent with changes in the microbial composition in all microcosms, was detected. After 10 months of cultivation, the divergently evolved consortia achieved up to 35.9 percent reduction of the total PCB concentration. Phylogenetic-analysis of the active Chloroflexi-related organohalide-respiring bacteria by partial sequencing of 16S rRNA genes in cDNA from microcosms with the highest PCB dechlorination activity revealed diverse and unique complexity of the populations. The predominant organohalide respirers were either affiliated with Dehalococcoides sp. and Dehalococcoides-like group (DLG) organisms or were composed of currently unknown distant clades of DLG bacteria. The present study should encourage researchers to explore the full potential of the indigenous PCB dechlorinating populations to develop effective bioremediation approaches that can perform the complete mineralization of PCBs in polluted environments.

Polychlorobenzenes and polychlorinated biphenyls in ash and soil from several industrial areas in North Vietnam: residue concentrations, profiles and risk assessment.

Polychlorinated benzenes (PCBzs) including penta- and hexachlorobenzene can be unintentionally formed from thermal processes in different industrial activities, and very little information is available on the contamination and emission characteristics of these new persistent organic pollutants from industries in Vietnam. In this study, contamination of PCBzs (including penta- and hexachlorobenzene, named PeCBz and HCB, respectively) and PCBs (including CB-28, 52, 101, 153, 138, 180) in fly ash, bottom ash and soil from combustion processes of waste incineration, metallurgy (steel making and zinc production) and cement production from several provinces in the Northern Vietnam, including Hai Duong, Hanoi, Bac Ninh, Hai Phong and Thai Nguyen, was preliminary investigated. The PCBzs concentrations in fly ash, bottom ash and soil ranged from 2.7 to 100ngg(-1), from 2.7 to 159ngg(-1) and from 0.28 to 33.9ngg(-1), respectively. Relatively high residues of PeCBz in fly ash and bottom ash from municipal waste incinerators in some provinces from the Northern Vietnam were encountered. Total PCBs concentrations ranged from 18.0 to 8260ngg(-1), from 1.0 to 10600ngg(-1) and from 14.5 to 130ngg(-1) for the fly ash, bottom ash and soil, respectively. Daily intakes of PeCBz, HCB and PCBs through soil ingestion and dermal exposure estimated for children ranged 0.33-9.93 (mean 3.14), 0.39-21.1 (mean 4.9) and 6.09-1530ng/kgbw/day (mean 346), respectively; and these intakes were about 4.7-5.4 times higher than those estimated for adult. The intakes of PeCBz and HCB were relatively low, while those for PCBs exceeded WHO TDI for some samples.

Chicago’s Sanitary and Ship Canal sediment: Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, brominated flame retardants, and organophosphate esters

The Chicago Sanitary and Ship Canal (CSSC) links the Great Lakes to the Mississippi River starting in downtown Chicago. In addition to storm water, the CSSC receives water from Chicago’s wastewater treatment plants (WWTP). Such effluents are known to be sources of organic pollutants to water and sediment. Therefore in 2013, we collected 10 sediment samples from the CSSC and measured the concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), brominated flame retardants, and organophosphate esters (OPEs). Geometric mean concentrations of the summed concentrations of 16 PAHs ranged from 11,000 to 420,000ng/gdw, with the highest concentrations located at each end of the canal. Total PCB concentrations had a geometric mean of 1400±500ng/gdw. Brominated flame retardants were separated into two groups: polybrominated diphenyl ethers (PBDEs) and non-PBDEs. Concentrations of PBDEs and those of the non-PBDE flame retardants had a geometric average of 83±19 and 7.0±5.8ng/gdw, respectively. The summed concentrations of 8 OPEs ranged from 470 to 2800ng/gdw, with the highest concentration detected at a site located downstream of the Stickney water reclamation plant. Using ANOVA results, some hypotheses on sources to the CSSC could be formulated: downtown Chicago is probably a source of PAHs, the Cal-Sag Channel may be a source of PCBs, and neither the WWTP nor the Cal-Sag Channel seem to be significant sources of brominated flame retardants or OPEs.

Impacts of PCB analytical interpretation uncertainties on dechlorination assessment and remedial decisions

Laboratory analyses of polychlorinated biphenyls (PCBs) often do not quantitate the 209 individual PCB congeners, thereby requiring analyst interpretation to determine individual congener concentrations. Error introduced during this interpretation is subsequently propagated to calculated surrogate variables, such as the number of chlorines per biphenyl (CPB), and the molar dechlorination product ratio (MDPR), which are used to assess the extent of dechlorination and inform remedial decisions. The present work applies a Monte Carlo (MC) analysis to assess current methods for quantitating co-eluting congeners and the errors that could occur in individual congeners and derived CPB and MDPR estimates. Synthetic chromatograms, which were created using two alternative methods (random assignment and assignment based on relative proportions in Aroclors) for assigning mass to co-eluting congeners, were compared to their fully-quantitated counterparts. The percent error introduced in total PCB (∑PCB) concentration ranges from approximately −60% to +50%. Similarly, the errors associated with CPB and MDPR estimates range from approximately −20% to +20% and −120% to +30%, respectively. Uncertainties introduced during congener analysis and propagated to surrogate variables can thus be substantial, and should be considered in assessments of the extent of dechlorination and associated remedial decisions.

Distribution and temporal variation of PCBs and PAHs in soils and sediments from an e-waste dismantling site in China

Temporal and geographical changes in the concentrations of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in soils and sediments around a typical e-waste dismantling area in China were systematically investigated. Dated soils and sediments from contaminated sites in the e-waste dismantling area were analyzed for PCBs congeners (1983–2012) and total PAHs (2004–2012). The results showed that the total concentration of PCBs ranged from 20.22 to 491.92 μg/kg dry weight (dw); the total concentration of PAHs ranged from 77.4 to 20,167.7 μg/kg dw; the sum of 6-dioxin-like (CB-28, 52, 101, 118, 138 and 180) and ∑PCBs in all the soils increased gradually from the early stage of pollution to the peak of pollution (317.85 and 927.30 μg/kg dw, respectively), but decreased after the control period of pollution (166.3 and 458 μg/kg dw, respectively). This work can provide information on pollution sources and evidence for short-range transport of POPs in e-waste dismantling areas, and useful data for e-waste recycling in China and other countries in the world.

Abundance and distribution of polychlorinated biphenyls (PCBs) in breast tissue

Many environmental chemicals accumulate in human tissues and may contribute to cancer risk. Polychlorinated biphenyls (PCBs) are associated with adverse health effects, but relationships between PCB exposure and breast cancer are unclear. In this study, we sought to determine whether bioaccumulation of PCBs differs within regions of the human breast and whether PCB levels are associated with clinical and pathological characteristics in breast cancer patients. Tissue sections (n=245) were collected from breast quadrants from 51 women with a diagnosis ranging from disease-free to metastatic breast cancer. Ninety-seven PCB congeners were assayed by high resolution gas chromatography. ANOVA was used to examine PCB distribution within the breast and relationships with clinical/pathological variables. Pearson product-moment correlations assessed relationships between age at mastectomy and PCB levels. PCBs were abundant in breast tissues with a median concentration of 293.4ng/g lipid (range 15.4–1636.3ng/g). PCB levels in breast tissue were significantly different (p<0.001) among functional groupings of congeners defined by structure-activity properties: Group I (28.2ng/g), Group II (96.6ng/g), Group III (166.0ng/g). Total PCB concentration was highly correlated with age at mastectomy, but the distribution of PCBs did not differ by breast quadrant. PCB levels were not associated with patient status or tumor characteristics. In conclusion, PCB congeners with carcinogenic potential were present at high levels in the human breast, but were not associated with clinical or pathological characteristics in breast cancer patients.

Increased levels of dioxin-like substances in adipose tissue in patients with deep infiltrating endometriosis.

Are the levels of biologically active and the most toxic dioxin-like substances in adipose tissue of patients with deep infiltrating endometriosis (DIE) higher than in a control group without endometriosis? DIE patients have higher levels of dioxins and polychlorinated biphenyls (PCBs) in adipose tissue compared with controls without endometriosis. Some studies have investigated the levels of dioxin-like substances, in serum samples, in patients with endometriosis, with inconsistent results. Case-control study including two groups of patients. The study group (DIE group) consisted of 30 patients undergoing laparoscopic surgery because of DIE. In all patients, an extensive preoperative work-up was performed including clinical exploration, magnetic resonance imaging (MRI) and transvaginal sonography. All patients with DIE underwent a confirmatory histological study for DIE after surgery. The non-endometriosis control group (control group), included the next consecutive patient undergoing laparoscopic surgery in our center due to adnexal benign gynecological disease (ovarian or tubal procedures other than endometriosis) after each DIE patient, and who did not present any type of endometriosis. During the surgical procedure 1-2 g of adipose tissue from the omentum were obtained. Dioxin-like substances were analyzed in adipose tissue in DIE patients and controls without endometriosis. The total toxic equivalence and concentrations of both dioxins and PCBs were significantly higher in patients with DIE in comparison with the control group (P < 0.05), mainly due to the significantly higher values of the two most toxic dioxins (2,3,7,8-tetrachlorodibenzo-p-dioxin [2,3,7,8-TCDD] and 1,2,3,7,8-pentachlorodibenzo-p-dioxin [1,2,3,7,8-PeCDD]) (P < 0.01 for each compound). The levels of furan 2,3,4,7,8-PeCDF were statistically higher in the DIE group compared with controls. Only four congeners of PCBs had toxic equivalence values and concentrations that were statistically higher in patients with DIE, but these included the most toxic and carcinogenic PCB-126 (PCB-114 P < 0.05; PCB-156 P < 0.05; PCB-189 P = 0.04; PCB-126 P < 0.01). Since few patients were recruited, the study is only exploratory. Our results need to be confirmed in larger and more heterogeneous population studies since environmental and even genetic factors involved in determining dioxins and PCBs widely vary in different countries. Furthermore, the strict eligibility criteria used may preclude generalization of the results to other populations and the surgery-based sampling frame may induce a selection bias. Finally, adipose tissue was obtained only from the omentum, and not from other adipose tissue of the body. Our results suggest a potential role of dioxin-like substances in the pathogenesis of DIE. Further studies are warranted to confirm our findings. None. Not applicable.

Polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs) in environmental samples from Ny-Ålesund and London Island, Svalbard, the Arctic

Polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs) were determined in environmental samples collected from Ny-Ålesund and London Island, Svalbard, the Arctic. Total PCB concentrations (∑25PCBs) varied from 0.57 to 2.52ngg−1 dry weight (dw) in soil, 0.30 to 1.16ngg−1dw in plants and 0.56 to 0.98ngg−1dw in reindeer dung. The non-Aroclor congener of CB-11 was predominant in most samples compared to other congeners, accounting for 16.0±9.8% to the ∑25PCBs. The ∑13PBDEs concentrations were 1.7–416, 36.7–495 and 28.1–104pgg−1dw in soil, plants and reindeer dung, respectively. The signature of enantioselective biotransformation was observed in all samples for chiral CB-95, whereas in parts of samples for other chiral PCBs. Bioaccumulation factors (BAFs) in six plant species varied within individual contaminant congeners and plant species, with BAFs less than 1 for ∑PCBs and higher than 1 for ∑PBDEs. BAF values decreased with increasing soil concentrations, suggesting that high background levels in soil restricted the accumulation of these contaminants by plants.

Occurrence, distribution and risk assessment of polychlorinated biphenyls and polybrominated diphenyl ethers in nine water sources

Water quality of water sources is a critical issue for human health in South China, which experiences rapid economic development and is the most densely populated region in China. In this study, the pollution of organohalogen compounds in nine important water sources, South China was investigated. Twenty six organohalogen compounds including seventeen polychlorinated biphenyls (PCBs) and nine polybrominated diphenyl ethers (PBDEs) were detected using gas chromatograph analysis. The concentrations of total PCBs ranged from 0.93 to 13.07ngL−1, with an average value of 7.06ngL−1. The total concentrations of nine PBDE congeners were found in range not detected (nd) to 7.87ngL−1 with an average value of 2.59ngL−1. Compositions of PCBs and PBDEs indicated the historical use of Aroclors 1248, 1254 and 1260, and commercial PBDEs may be the main source of organohalogen compounds in water sources in South China. The nine water sources could be classified into three clusters by self-organizing map neural network. Low halogenated PCBs and PBDEs showed similar distribution in the nine water sources. Cancer risks of PCBs and PBDEs via water consumption were all below 10−6, indicating the water quality in the nine water sources, South China was safe for human drinking.

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

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.

Dioxin-like PCB levels in maternal and umbilical cord sera of people living near dump sites in southern Italy: a pilot study of biomonitoring.

The "Triangle of Death" is an area of southern Italy highly polluted due to the presence of numerous illegal waste sites. To assess whether environmental contamination could produce an increased intake of harmful chemicals, we determined the serum levels of the 12 polychlorinated biphenyls (PCBs) indicated as "dioxin like" by the World Health Organization (WHO) in both maternal blood serum and umbilical cord blood serum of people residing in that area. The study was performed on 32 pregnant women and cord serum of their 32 newborn babies. Maternal serum concentrations ranged from 0.019 to 10.426ng/mL (mean 1.590 ± 2.002ng/mL), while umbilical serum concentrations ranged from 0.018 to 16.980ng/mL (mean 1.858 ± 3.558ng/mL). To normalize the toxic impact of the different congeners, the levels were expressed as WHO-TEQ, i.e., toxic equivalent concentrations. Total PCB concentrations (ΣPCBs WHO-TEQ 1998) were 0.297TEQ-ng/mL in maternal serum and 0.663TEQ-ng/mL in cord blood. These levels are significantly higher not only than those found in subjects resident in other areas but also in comparison to those reported in other published studies. This suggests that the exposure of both pregnant mothers and their fetuses to environmental pollution could produce a high intake of PCBs. The study may be important for the public health authorities to evaluate the level of exposure to environmental pollutants in human residents in the Triangle of Death.

Characterization and risk assessment of polychlorinated biphenyls in city park soils of Xi'an, China.

Polychlorinated biphenyl (PCB) concentrations in surface soil samples (0-10 cm) from 23 city parks (8 urban and 15 suburban) from Xi'an, China were presented. The average concentration of Σ7 PCBs among all the sites was 1.68 ng g(-1) dry weight. High detection frequency (100 %) of PCB 28 and PCB 52 suggested wide occurrence of PCB contaminations in Xi'an. Among these PCBs, PCB 28, 52 and 153 were the most dominant compounds (14.9 %, 39.3 % and 9.5 % of the Σ7 PCBs on average, respectively). "Urban fractionation effect" was found in Xi'An. In other words, PCB concentrations were higher in the urban city park soils than those in suburban park soils. The PCB contamination in Xi'an city park soils were at a low level based on the Dutch guideline. However, dioxin-like PCB congeners were detected from 12 parks, which indicated further investigation was urgently required in future. Furthermore, total PCB concentrations were used to evaluate the cancer risk via ingestion, dermal and inhalation and the results showed that the total cancer risk was at the very low level in this area.

Assessment of contaminant levels in fish from the Toronto waterfront area

The Toronto waterfront area of Lake Ontario is part of the Toronto and Region Area of Concern (AOC), partly due to elevated contaminant levels in fish and the resulting restrictive fish consumption advisories. Data collected by the Province of Ontario were used to investigate long-term (1975–2011) temporal trends of mercury, polychlorinated biphenyls (PCBs), mirex, and toxaphene levels in multiple fish species collected from the Toronto waterfront area. Recent (2000–2012) mercury and total PCB levels in fish from the Toronto waterfront area were compared to those for other regions, including other AOCs, of the Canadian waters of the Great Lakes. A similar comparison of fish PCB levels was also conducted for the Canadian AOCs for a historical scenario. Mercury and PCB levels in fish from the Toronto waterfront area demonstrated significant decreasing trends over time in multiple species, and recent mercury levels are well below the current consumption advisory benchmarks. In some cases, PCB levels remain above the current consumption advisory benchmarks and above the levels observed in fish from other AOC and non-AOC regions of the Canadian Great Lakes. Half-life calculations for these species indicate that it may take 8–26 years for total PCB concentrations in certain fish species to decrease below the current consumption advisory benchmarks. Sustained monitoring of PCBs in fish from the Toronto waterfront area is recommended to aid in ensuring that recovery continues.

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

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.

Seasonal Variation and Gas/Particle Partitioning of PCBs in Air from Central Urban Area of an Industrial Base and Coastal City -Tianjin, China

ABSTRACTThe 26 air samples were collected from Tianjin urban areas from July 2010 to May 2011 for the analysis of 86 PCB congeners to investigate the gas/particle partitioning of PCBs. The total PCBs concentration (in pg/m3) ranged from 31.28 to 650.33 (mean: 273.77) and showed a significantly seasonal variation as summer > autumn > spring > winter. Gas PCBs accounted for 80.79% of total PCBs. The fraction of each gas PCB homolog increased with the decreasing chlorine atoms. The contribution of gas PCBs to total PCBs showed a strong seasonal variation with summer (94.07%) > autumn (78.91%) > spring (78.19%) > winter (56.02%). Tri-, tetra- and penta-PCBs were the predominantly homologs in Tianjin atmosphere. The natural logarithm of partial pressure of PCBs were well correlated with the inverse absolute environmental temperature (R = 0.79). The steep slope of –4933.64 obtained from Clausius–Clapeyron (C.C) plot indicated the influence of local PCBs sources. In generally, the C.C slopes and the surface-air exchange enthalpy (∆HSA) for different PCB homologs increased with the increasing chlorine atoms. The fraction of particle bound PCBs were underestimated for PCBs with PL0 > 10–3.85 Pa and overestimated for PCB congeners with PL0 < 10–3.85 Pa by Junge-Pankow model. The logarithm of particle/gas partitioning coefficients (log KP) of PCBs were well correlated with the logarithm of respective sub-cooled vapor pressures (log PL0) (R = 0.72) and the octanol-air partition coefficient (log KOA) (R = 0.77). The slopes for log KP against log PL0 and log KOA plots were –0.44 and 0.48, deviated significantly from the expected –1 and +1 for the equilibrium state of gas/particle partitioning, possibly explained by the emission of PCBs and particles from the local industries and other sources. The TEQ concentrations (fg/m3) for 12 dioxin-like PCB congeners ranged from 35.628 to 612.796 with the mean value as 144.878.