Sources Of Polychlorinated Biphenyls Research Articles

Persistent Organic Pollutants: Not Finished Yet

Although polychlorinated biphenyls (PCBs) were banned in the United States in 1977, they persist in the environment. These bioaccumulative chemicals can damage the immune, reproductive, endocrine, and nervous systems. When looking for environmental sources of PCBs, scientists generally measure dietary intake from fish, meat, and milk. However, older wood floor finishes that harbor PCBs may present an underestimated route for exposure, finds Ruthann Rudel, a toxicologist at the nonprofit Silent Spring Institute in Newton, Massachusetts. Animal studies show that PCBs decrease the size of the thymus gland and suppress antibody production and immune responses. People exposed to PCBs can suffer from skin rashes, changes in blood and urine that can indicate liver damage, irregular menstrual cycle, lowered immune response, fatigue, and headache. In children, poor cognitive development is reported. The International Agency for Research on Cancer classifies PCBs as probable human carcinogens. From 1999 to 2001, Rudel and her colleagues monitored 89 indoor pollutants linked to breast cancer in 120 homes on Cape Cod, where breast cancer rates are among the highest in Massachusetts. As reported 13 September 2003 in Environmental Science & Technology, detectable levels of PCBs were found in about a third of the residences, and two houses had exceedingly high levels of PCBs in air and dust. Five years later, Rudel revisited these two houses to measure air and dust concentrations of the congeners PCB52, PCB105, and PCB153 as well as occupants’ blood levels of 10 congeners measured in 1999–2002 as part of the National Health and Nutrition Examination Survey (NHANES). Air and dust levels remained exceptionally high, with dust values ranging from 21 to 190 μg/g—up to 20 times higher than reported in other studies of indoor PCB exposure. Three of the occupants, all of whom had lived in their homes for more than a decade, showed elevated blood levels of PCBs as high as 1,520 ng/g, placing them in the top 5% of people living in the United States. A fourth occupant, who had lived in her house for only six months, had a blood level of 179 ng/g. The study is published as volume 7, article 2 (2008) of the online journal Environmental Health. None of the occupants ate enough fish to account for the high blood levels of PCBs. “We were really stumped,” says Rudel. Then the homeowner with the highest PCB levels recalled that 50 years earlier he had finished his wood floors with high-gloss “Fabulon” varnish. In the 1950s and 1960s, Fabulon was a popular coating sold nationwide to give floors a “bowling-alley shine.” A now-discontinued reference manual, Clinical Toxicology of Commercial Products, confirmed that Fabulon contained PCBs between 1950 and 1969. Before being banned, PCBs were not only added to varnishes but also to caulk, paint, linoleum, and ceiling tiles, where they served as stabilizers, sealants, and adhesives. The same homeowner had sanded one of his floors just before Rudel returned to collect samples for the latest study. However, the floors in the other house had not been refinished in years. Rudel suspects, but has not confirmed, that the floors may be giving off PCBs, with sanding releasing even higher levels of dust packed with PCBs. She hopes to conduct further research—such as whether a peak time for exposure occurs when sanding off PCB-laced finishes, or whether carpets later laid over finished wood floors limit airborne exposure—that might shed light on safer ways to remove PCBs. What can homeowners do, pending further information? “I’m not happy about how little I can tell people,” Rudel admits. Foremost, she advises not sanding old wood floors. PCB analysis is expensive, and Rudel knows of no laboratories that service homeowners. However, some floor-finishing businesses offer a dustless sanding process that pumps toxic dust into outdoor tanks. “Rudel certainly found an unrecognized source of PCBs that underscores the importance of inhalation as an underappreciated but important source of exposure,” says David Carpenter, a public health physician at the University at Albany, State University of New York. The results add to a growing body of awareness that building materials can be a significant source of PCBs indoors. “The assumption that PCBs stay put simply is not true,” Carpenter says.

Emissions of polychlorinated biphenyls (PCBs) from sludge drying beds to the atmosphere in Chicago

Ambient air PCB concentrations in the Lake Calumet region in Southeast Chicago have been found to be significantly higher than in nearby non-urban areas. This area is highly industrialized and also contains municipal sludge drying facilities and landfills. In an effort to quantify the importance of the sludge drying facilities to the elevated concentrations, upwind/downwind air samples from the Calumet East sludge drying bed were obtained between April and October 2002. For these samples, the downwind minus upwind (downwind–upwind) concentration varied from 0.33 to 1.27 ng m −3 for non-northeast (NE) direction winds suggesting sludge drying is a source of PCBs to the atmosphere. However, the upwind concentrations were higher than the downwind for winds from the NE of the sampling site suggesting more significant source(s), possibly Lake Calumet or the so called “Cluster site” NE of the sludge drying beds. Flux chamber experiments carried out during the sampling period measured average PCB fluxes of 210 ng m −2 h −1 (range 43–910 ng m −2 h −1) which resulted in an overall flux of 0.005 kg day (d) −1 (∼2 kg yr −1). A developed regression equation between moisture content and sludge concentration estimated higher PCB losses of 0.26 kg d −1 (∼95 kg yr −1). Although these two approaches yielded different values, they both indicate that the emission from the Calumet East sludge drying beds were of minimal importance when compared to the total estimated amount of 2–70 kg d −1 (700–2100 kg yr −1) of PCBs entering the Chicago atmosphere.

PCB-containing wood floor finish is a likely source of elevated PCBs in residents' blood, household air and dust: a case study of exposure

BackgroundPolychlorinated biphenyls (PCBs) are persistent pollutants identified worldwide as human blood and breast milk contaminants. Because they bioaccumulate, consumption of meat, fish, and dairy products predicts human blood concentrations. PCBs were also used widely in building materials, including caulks and paints, but few studies have evaluated the contribution of these exposures to body burden.MethodsIn an earlier study, we detected PCBs in indoor air in 31% of 120 homes on Cape Cod, MA. Two of the homes had much higher concentrations than the rest, so we retested to verify the initial finding, evaluate blood PCB concentrations of residents, and identify the PCB source.ResultsAir and dust concentrations remained elevated over 5 years between initial and follow-up sampling. Blood serum concentrations of PCBs in residents of the homes were generally elevated above the 95th percentile of a representative sample of the US population. Serum concentrations in residents and air and dust concentrations were especially high in a home where a resident reported use of PCB-containing floor finish in the past, and where the floor of one room was sanded and refinished just prior to sample collection.ConclusionThis case-study suggests that PCB residues in homes may be more significant contributors to overall exposure than diet for some people, and that use of a commercially-available PCB-containing wood floor finish in residences during the 1950s and 1960s is an overlooked but potentially important source of current PCB exposure in the general population.

Passive Air Sampler (PAS)와 기체/입자 분배모델을 이용한 대기 중 PCB 농도 산정

Polyurethane foam-disk passive air samplers (PAS) were deployed in a southern area of Korea for three months. The target compounds were 12 coplanar polychlorinated biphenyls (PCBs). The congener profiles measured in this study were the same as those in ambient air and emission gas from the incinerator. A gradient of the total PCBs in different regions (industrial>residential>rural) was observed, suggesting the industrial complex may be an important source of coplanar PCBs. In general, only gas-phase compounds are mainly sequestrated by PAS. In order to estimate the concentration of particle-phase PCBs, a gas/particle partition model was used. A combined result (gas+particle-phase PCBs) was compared with previous results, indicating that the level of coplanar PCBs in our study area is comparable to those in other urban sites in the world. The validation of this method for estimating the total concentration is required through additional backup studies.

Monitoring of polychlorinated biphenyl contamination and estrogenic activity in water, commercial feed and farmed seafood

We evaluated the concentration and congener distribution of seven "target" polychlorinated biphenyls (PCBs) present in water collected in different aquaculture farms of the Mediterranean area, commercial feeds, and farmed seafood. PCBs were present in feed and in tissues of all the analysed organisms at levels ranging from 1.96 ng g(-1) to 124.00 ng g(-1) wet weight, and in 10.5% of the water samples, at levels from under detection limit to 33.0 ng l(-1) with total PCB concentrations significantly higher in samples from the Tyrrhenian Sea than the Adriatic Sea. PCB congener distribution in tissues resembled that of feed, suggesting that commercial feed is an important source of PCBs. The estrogenicity of organic extracts of the samples was also evaluated by using an in vitro yeast reporter assay. Estrogenic activity higher than 10% of the activity induced by 10 nM 17 beta-estradiol was observed in 20.0% of seafood samples and 15.8% of water samples. Seafood and water samples from the Tyrrhenian Sea were more frequently estrogenic than the Adriatic ones (16.45 versus 4.08%). A significant correlation of total PCB concentrations on biological activity was observed for sea bass and mussels from the Adriatic Sea (p < 0.045 and p < 0.04, respectively), and for sea bass of the Tyrrhenian Sea (p = 0.05). These results indicate the need of an integral approach in the exposure assessment to potential toxic compounds for human via food.

Record high peaks in PCB concentrations in the Arctic atmosphere due to long-range transport of biomass burning emissions

Abstract. Soils and forests in the boreal region of the Northern Hemisphere are recognised as having a large capacity for storing air-borne Persistent Organic Pollutants (POPs), such as the polychlorinated biphenyls (PCBs). Following reductions of primary emissions of various legacy POPs, there is an increasing interest and debate about the relative importance of secondary re-emissions on the atmospheric levels of POPs. In spring of 2006, biomass burning emissions from agricultural fires in Eastern Europe were transported to the Zeppelin station on Svalbard, where record-high levels of many air pollutants were recorded (Stohl et al., 2007). Here we report on the extremely high concentrations of PCBs that were also measured during this period. 21 out of 32 PCB congeners were enhanced by more than two standard deviations above the long-term mean concentrations. In July 2004, about 5.8 million hectare of boreal forest burned in North America, emitting a pollution plume which reached the Zeppelin station after a travel time of 3–4 weeks (Stohl et al., 2006). Again, 12 PCB congeners were elevated above the long-term mean by more than two standard deviations, with the less chlorinated congeners being most strongly affected. We propose that these abnormally high concentrations were caused by biomass burning emissions. Based on enhancement ratios with carbon monoxide and known emissions factors for this species, we estimate that 130 and 66 μg PCBs were released per kilogram dry matter burned, respectively. To our knowledge, this is the first study relating atmospheric PCB enhancements with biomass burning. The strong effects on observed concentrations far away from the sources, suggest that biomass burning is an important source of PCBs for the atmosphere.

The use of leeches and logit log-linear contingency models to assess and monitor aquatic PCB contamination originating from mid-Canada radar line site 050

Abandoned military sites in northern North America are relics of the Cold War and sources of polychlorinated biphenyls (PCBs). In the late 1990s, the Canadian federal and provincial governments began the cleanup of the mid-Canada radar line in Ontario, Canada. The first site to be remediated was Site 050 (Fort Albany First Nation) in 2001; however, the community remains concerned that contaminants may have moved prior to, during, and after remediation into the Albany River directly adjacent to Site 050. Thus, the Albany River was monitored (1999, 2001, 2002) during the remediation process to determine if the cleanup itself further contaminated the aquatic compartment, using leeches (Haemopis spp.) as bioindicators. Few organochlorines were found in leeches at levels higher than the detection limit, aside from PCBs. Leech data from the present study indicated that PCB levels were significantly higher near Site 050 than the control site upstream, indicating point source contamination from Site 050. The temporal trend in leech contaminant data indicated an increase in PCB contaminant load from 1999 (pre-remediation) to 2001 (immediately post-remediation), but this difference was not statistically significant due to high variances. Nevertheless, logit log-linear contingency modeling did reveal that immediately after cleanup (2001), contaminants (CBs 99, 118, 128, 156, 170, 183) in leeches were detected significantly more frequent than expected. When taken together, leech body burden and frequency of detection data suggest that the remediation process itself further contaminated the aquatic environment, if only temporarily. Lastly, the removal of the terrestrial source of PCBs during remediation did remove the source of aquatic contaminants in that body burden of contaminants in leeches were significantly lower a year after cleanup.

Source identification of atmospheric PCBs in Philadelphia/Camden using positive matrix factorization followed by the potential source contribution function

The concentrations of gas-phase polychlorinated biphenyls (PCBs) in the atmosphere of the Camden, NJ, USA are elevated by as much as 20 times over regional background. These high PCB levels are a concern because they lead to atmospheric deposition loadings of PCBs to the tidal Delaware River that exceed the entire total maximum daily load (TMDL). Two models were applied to the atmospheric PCB concentration data from Camden in an attempt to identify the PCB source types and regions. Positive matrix factorization (PMF) was used to identify the source types. Four factors were identified which are thought to represent sources such as volatilized Aroclors and particle-phase PCBs. The potential source contribution function (PSCF) model was then used to identify the geographic source regions by examining the origination points for air parcels that result in high PCB concentrations at the Camden receptor site. The PSCF model for ΣPCBs indicates PCB source regions throughout the Philadelphia–Camden metro area, including portions of both Pennsylvania and New Jersey. The PSCF plots for the resolved PMF factors suggest that factors 1–4 show fewer distinct source regions, indicating that their sources are diffuse and/or lie very close to the receptor site. The PSCF plots for factors 2 and 3 reveal very different source regions. Factor 2 primarily arises from the city of Philadelphia, whereas factor 3 originates in southern New Jersey and south of Philadelphia. This study demonstrates the utility of the combined PMF/PSCF approach in identifying atmospheric PCB source types and regions.

Chiral Source Apportionment of Polychlorinated Biphenyls to the Hudson River Estuary Atmosphere and Food Web

The New York/New Jersey Harbor Estuary is subject to significant contamination of polychlorinated biphenyls (PCBs) from numerous sources, including the historically contaminated Upper Hudson River, stormwater runoff and sewer overflows, and atmospheric deposition from PCBs originating from the surrounding urban area. However, the relative importance of these sources to the estuary's food web is not fully understood. Sources of PCBs to the estuary were apportioned using chiral signatures of PCBs in air, water, total suspended matter, phytoplankton, and sediment. PCBs 91, 95, 136, and 149 were racemic in the atmosphere of the estuary. However, the other phases contained nonracemic PCB 95 and to a lesser extent PCB 149. Thus, the predominant atmospheric source of these congeners is likely unweathered local pollution and not volatilization from the estuary. The similarity in chiral signatures in the other phases is consistent with dynamic contaminant exchange among them. Chiral signatures in the dissolved phase and total suspended matter were correlated with Upper Hudson discharge, suggesting thatthe delivery of nonracemic contaminated sediment from the Upper Hudson, not the atmosphere, controls phytoplankton uptake of some PCBs. Thus, measures to control PCB contamination in the Upper Hudson should be effective in reducing loadings to the estuary's aquatic ecosystem.

Ambient concentrations and source apportionment of PCBs and trace elements around an industrial area in Izmir, Turkey

Atmospheric concentrations of polychlorinated biphenyls (PCBs) and trace elements were measured at two sites (Industrial and Urban) located around the Aliaga industrial region, Izmir, Turkey. Average ∑ 36PCB concentrations were 3136 ± 824 and 1371 ± 642 pg m −3 for summer and winter periods, respectively in the Industrial site and they were 314 ± 129 and 847 ± 610 pg m −3 in the Urban site. The elemental content showed that the PM 10 measured at the Industrial site was dominated by terrestrial elements and trace elements emitted by the iron–steel plants (Fe, Zn and Pb). The elemental profile at the Urban site was typical for Aegean Region that was dominated by terrestrial elements (Ca, Al, Mg) and sea salt (Na). Sources of particle-phase PCBs and trace elements were identified using factor analysis (FA) and were apportioned by chemical mass balance (CMB) model. FA suggested that the steel industry, fuel oil combustion, or the nearby vinyl chloride process in the petrochemical plant, and soil were significant PCB sources. CMB results showed that at the Industrial site, the contribution of steel industry and soil to particle-phase PCBs were 71% and 22%, respectively, while at the Urban site, the contributions were 33% and 49%, respectively. Steel industry was also the dominant contributor for trace elements around the site. Fugacity calculations in air and soil showed that the soil acts as a secondary source to the atmosphere for low molecular weight PCBs especially in summer and as a sink for the higher molecular weight ones.

Polychlorinated biphenyls (PCBs) in San Francisco Bay

San Francisco Bay is facing a legacy of polychlorinated biphenyls (PCBs) spread widely across the land surface of the watershed, mixed deep into the sediment of the Bay, and contaminating the Bay food web to a degree that poses health risks to humans and wildlife. In response to this persistent problem, water quality managers are establishing a PCB total maximum daily load (TMDL) and implementation plan to accelerate the recovery of the Bay from decades of PCB contamination. This article provides a review of progress made over the past 15 years in managing PCBs and understanding their sources, pathways, fate, and effects in the Bay, and highlights remaining information needs that should be addressed in the next 10 years. The phaseout of PCBs during the 1970s and the 1979 federal ban on sale and production led to gradual declines from the 1970s to the present. However, 25 years after the ban, PCB concentrations in some Bay sport fish today are still more than ten times higher than the threshold of concern for human health. Without further management action it appears that the general recovery of the Bay from PCB contamination will take many more decades. PCB concentrations in sport fish were, along with mercury, a primary cause of a consumption advisory for the Bay and the consequent classification of the Bay as an impaired water body. Several sources of information indicate that PCB concentrations in the Bay may also be high enough to adversely affect wildlife, including rare and endangered species. The greater than 90% reduction in food web contamination needed to meet the targets for protection of human health would likely also generally eliminate risks to wildlife. PCB contamination in the Bay is primarily associated with industrial areas along the shoreline and in local watersheds. Strong spatial gradients in PCB concentrations persist decades after the release of these chemicals to Bay Area waterways. Through the TMDL process, attention is being more sharply focused on the PCB sources that are controllable and contributing most to PCB impairment in the Bay. Urban runoff from local watersheds is a particularly significant pathway for PCB entry into the Bay. Significant loads also enter the Bay through Delta outflow (riverine input). Recent studies have shown that erosion of buried sediment is occurring in large regions of the Bay, posing a significant problem with respect to recovery of the Bay from PCB contamination because the sediments being eroded and remobilized are from relatively contaminated buried sediment deposits. In-Bay contaminated sites are likely also a major contributor of PCBs to the Bay food web. Dredged material disposal, wastewater effluent, and atmospheric deposition are relatively minor pathways for PCB loading to the Bay. Priority information needs at present relate to understanding the sources, magnitude of loads, and effectiveness of management options for urban runoff; the regional influence of in-Bay contaminated sites; remobilization of PCBs from buried sediment; historic and present trends; in situ degradation rates of PCBs; reliable recovery forecasts under different management scenarios; the spatial distribution of PCBs in soils and sediments; and the biological effects of PCBs in interaction with other stressors. The slow release of pollutants from the watershed and the slow response of the Bay to changes in inputs combine to make this ecosystem very slow to recover from pollution of the watershed. The history of PCB contamination in the Bay underscores the importance of preventing persistent, particle-associated pollutants from entering this sensitive ecosystem.

Distribution of Chlorinated Organic Pollutants in a Wide Variety of Soils from Europe and Asia: A Multivariate Statistical Approach

Principal component analysis was used to interpret the levels of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) previously determined in a wide variety of soils from Europe and Asia to (1) examine the interdependencies among them and chosen soil charaeteristics and (2) reveal PCB- and OCP-soil patterns throughout Europe and Asia. Loading values suggested correlations between the levels of certain compounds and soil characteristics, revealing the underlying structure of analyzed data; humus content, pH, and density correlated with the contents of p,p'-DDT, beta-hexachlorocyclohexane (HCH) and gamma-HCH, and clay content correlated with the concentrations of alpha-HCH and PCB 28. Component scores reflected relatively low concentrations of six "marker" PCBs in most of the soils, pointing out the outliers in the proximity of the local PCB sources. PCB loads in the 1990s and early 2000s were lower than the ones in 1980 and 1956, and they coincided with the soil levels in 1944. PCBs 138, 153, and 180 had the greatest influence of the six investigated congeners on soil-pattern differences. In relation to the OCP soil loads, the score plot revealed regions with recent and/or enhanced application of DDT and HCH.

Concentrations and Chiral Signatures of Polychlorinated Biphenyls in Outdoor and Indoor Air and Soil in a Major U.K. Conurbation

Concentrations and chiral signatures of polychlorinated biphenyls (PCBs) were measured in outdoor air (using polyurethane foam (PUF)--disk passive samplers) and surface soil samples taken at approximately monthly intervals over 1 year at 10 locations on a rural-urban transect across the West Midlands of the U.K. In both air and soil, concentrations clearly decrease with increasing distance from the city center, supporting the existence of an urban "pulse", that indicate the West Midlands conurbation to be a source of PCBs to the wider environment. Concentrations of PCBs in outdoor air samples in this study are well below those reported previously for indoor air in the West Midlands. This, combined with comparison of chiral signatures in outdoor air and soil with those in samples of indoor air taken in the West Midlands, suggest strongly that the principal contemporary source of PCBs in this conurbation is ventilation of indoor air and not volatilization from soil. Future reductions in PCB concentrations in outdoor air and ultimately human exposure appear best achieved by action to remove remaining sources of PCBs from existing structures.

Polycyclic aromatic hydrocarbons and polychlorinated biphenyls in urban soils from Kathmandu, Nepal

Kathmandu, the capital of Nepal, faces increasing environmental problems such as heavy air pollution and lack of proper waste management. The aim of this study was to examine if the soils are also affected by pollution, with the focus on polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The sum of 20 PAHs in surface soils ranged between 184 and 10279 μg kg −1. The most abundant PAHs were perylene (14.6%), benzo( b+ j+ k)flouranthene (10.7%), naphthalene (10.7%) and phenanthrene (9.8%), with perylene concentrations varying strongly. The significantly more positive δ 13C values of perylene in samples with elevated concentrations indicate biological production, possibly by anaerobic degradation of perylene quinones. PAH ratios also indicate the influence of petrogenic PAH sources, especially at petrol stations and some street samples. The sum of 12 PCBs ranged from 356 to 44710 ng kg −1. The most abundant were congeners 52 (19.4%), 101 (14.3%), 118 (13.4%) and 138 (11.7%). The low PCB concentrations and pattern were interpreted as a diffuse background contamination being the main PCB source in the urban soils. Indications for recent contamination were found in river sediments from the inner city, as well as in industrial and street samples. Classified by land use, the samples taken from the gutter contained the highest PAH and PCB concentrations as a result of accumulation. The lowest values were found in surface soils from Swayambunath (a park) and a garden area. A gradual decrease in concentration with depth was present for both compound classes in the profiles sampled at Swayambunath. No trend was visible in the garden profiles as a result of soil disturbance of the soil by agricultural treatment. Enhanced microbial degradation and volatilization in the warm/humid monsoon climate is probably the main cause for low pollutant concentrations. Increased photodegradation and the short accumulation period might be other important factors. Concerning its state of soil pollution, Kathmandu fits rather well into a global distribution pattern of persistent organic pollutants, with high concentrations in temperate (higher latitude) regions and very low ones in the tropics (lower latitude regions) due to global distillation.

Receptor modeling for analyzing PCDD/F and dioxin-like PCB sources in Hong Kong

A total of 96 ambient air samples were collected from January 2004 to December 2004 for the investigation of dioxins (polychlorinated dibenzo-para-dioxins and polychlorinated dibenzofurans [PCDD/Fs]) and dioxin-like profile for polychlorinated biphenyls (PCBs) in the atmosphere of Hong Kong. Two-day back-trajectories were obtained using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model from National Oceanic and Atmospheric Administration (NOAA) Air Resources Laboratory. Receptor models – potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) – were built based on the measured PCDD/Fs and dioxin-like PCBs total toxic equivalent (TEQ) concentrations. Both models were modified in this study so as to integrate the information obtained from three sampling sites in Hong Kong. The PSCF modeling resolved two main PCDD/F and dioxin-like PCB polluting paths from Mainland China. In line with previous studies, the northerly path around the Pearl River Delta might be one of the pollution sources of Hong Kong air. On the other hand, the receptor models also indicated another potential northeasterly source from Yangtze River Delta, which was seldom mentioned as the source region of Hong Kong air. Results from the CWT modeling suggested that the most toxic air mass affecting Hong Kong is probably attributable to the northeast path rather than the north path.

Temporal and Spatial Trends of Atmospheric Polychlorinated Biphenyl Concentrations near the Great Lakes

Polychlorinated biphenyl (PCB) concentrations were measured in the atmosphere at six regionally representative sites near the five Great Lakes from 1990 to 2003 as part of the Integrated Atmospheric Deposition Network (IADN). Concentration data for several individual PCB congeners and for total PCBs were analyzed for temporal and spatial trends after correcting for the temperature dependency of the partial pressures. Atmospheric PCB concentrations are decreasing relatively slowly for tetra- and pentachlorinated congeners, an observation that is in agreement with primary emissions modeling. Relatively rapid decreases in PCB concentrations at the sites near Lakes Michigan and Ontario may reflect successful reduction efforts in Chicago and Toronto, respectively. Atmospheric PCB concentrations near Lakes Superior and Huron are now so low that the air and water concentrations may be close to equilibrium. Atmospheric PCB concentrations at sites near Lakes Michigan, Erie, and Ontario are relatively higher than those measured at sites near Lakes Superior and Huron. The highest PCB level was observed at the site near Lake Erie, most likely due to nearby urban activity. However, this relatively higher concentration is still 6-10 times lower than that previously reported at the Chicago site. A correlation between average gas-phase PCB concentration with local population indicates a strong urban source of PCBs. The temperature dependence of gas-phase PCB concentrations is similar at most sites except at Burnt Island on Lake Huron, where very low concentrations, approaching virtual elimination, prevent reliable temperature correlation calculations.

Air−Water Exchange of Polychlorinated Biphenyls in the Delaware River

The air-water exchange of polychlorinated biphenyls (PCBs) often results in net volatilization, which is thought to be the most important loss process for PCBs in many systems. Previous investigations of the air-water exchange of PCBs have been hampered by difficulties in treatment of the uncertainty in the calculation of air/water fugacity ratios. This work presents a new framework for the treatment of uncertainty, where uncertainty in physical constants is handled differently from random measurement uncertainty associated with random samples, and it further investigates the sorption of PCBs to colloids (dissolved organic carbon). Simultaneous measurements of PCBs in the air and water of five water quality management zones of the Delaware River were taken in 2002 in support of the total maximum daily load (TMDL) process. Gas-phase concentrations of IPCBs ranged from 110 to 1350 pg m(-3), while dissolved water concentrations were between 420 and 1650 pg L(-1). Shallow slopes of log Koc vs. log Kow plots indicated a colloidal contribution to the apparent dissolved-phase concentrations, such that a three-phase partitioning model was applied. Fugacity ratios for individual congeners were calculated under the most conservative assumptions, and their values (log-transformed) were examined via a single-sample T-test to determine whether they were significantly less than 1 at the 95% confidence level. This method demonstrated that air-water exchange resulted in net volatilization in all zones over all cruises for all but seven high molecular weight congeners. Calculated net fluxes ranged from +360 to +3000 ng m(-2) d(-1) for sigma PCBs. The colloidal correction decreased the volatilization flux of sigma PCBs by approximately 30%. The decachlorinated congener (PCB 209), exhibited unusually high concentrations in the suspended solids, especially in the southern portions of the river, indicating that there is a distinct source of PCB 209 in the Delaware River.

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

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 −1 ΣPCBs 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.

PCBs, PCNs and PBDEs in sediments and mussels from Qingdao coastal sea in the frame of current circulations and influence of sewage sludge

Influence of current circulation and sewage sludge on spatial distributions of polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and polybrominated diphenyl ethers (PBDEs) in sediments and mussels from the Qingdao coastal sea were investigated. Total concentrations of PCBs, PCNs and PBDEs in sediments ranged 6.5–32.9, 0.2–1.2, and 0.1–5.5 ng g −1 dry wt, respectively. The maximum concentrations were all found near the Haibo River mouth, affected by sewage sludge input from the river. Under the current system in Jiaozhou Bay the organic pollutants were subject to deposit on the east side of the bay and trapped inside the bay. Sewage sludge was an important source of PCBs, PCNs and PBDEs in the bay and exponentially magnified the enrichment of PCBs. On the other hand, the congener profiles of PCBs in sediments outside the bay may signify an atmospheric source of PCBs. Total Concentrations of PCBs, PCNs and PBDEs in mussels were 61.4–88.6, 9.0, and 13.8 ng g −1 lipid, respectively. Mussels enriched significantly PCBs, PCNs and PBDEs relative to the sediments. The total toxicity equivalent quantities (TEQs) of PCNs in mussels were generally lower than that of PCBs. The fluxes of the total PCBs and their TEQs have been decreased steadily since 1950s. The lower chlorinated/brominated congeners of PCNs and PBDEs may exhibit a greater tendency due to less lipophilic and thus a greater probability of being affected by the current circulation in the bay.

Women’s Health: Endometriosis and PCB Exposure

Vol. 114, No. 7 EnvironewsOpen AccessWomen’s Health: Endometriosis and PCB Exposure Carol Potera Carol Potera Search for more papers by this author Published:1 July 2006https://doi.org/10.1289/ehp.114-a404aCited by:2AboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit Endometriosis may be related to exposure to persistent pollutants such as polychlorinated biphenyls (PCBs), according to research published in the May 2006 issue of Chemosphere. This gynecological disorder linked to infertility afflicts 10% of U.S. women of reproductive age. Researchers measured blood PCB levels in women undergoing laparoscopy for suspected endometriosis or other gynecological conditions. Higher levels of PCBs were detected in women with histologically confirmed endometriosis compared with controls.Toxicologist Elena De Felip of the Istituto Superiore di Sanità in Rome and her colleagues measured 11 PCB congeners that are most abundant in human tissue. In 80 women aged 20 to 40, the sum of all congeners was 1.6 times higher in the 40 women diagnosed with endometriosis than in controls. Three congeners, PCBs 138, 153, and 180, were particularly higher in women with endometriosis. These three congeners have been reported to have estrogenic activity and to interfere with hormone-regulated processes.PCBs have been used since the 1930s, mainly in electrical equipment. Although no longer manufactured, these persistent chemicals accumulate in the food chain; today meat, fish, eggs, and milk are chief sources of PCBs. But diet seems unable to explain the difference in PCB levels detected in the two groups of women, since “the dietary habits of the women were basically the same,” says De Felip.De Felip suspects that differences in how women detoxify and eliminate PCBs from the body may explain the disparity. These processes are mediated by polymorphic enzymes; therefore, she says, differences in toxicokinetic activity may represent the basis for the higher concentrations detected in women with endometriosis and may also be related to higher or lower susceptibility to that condition.Studies of PCBs and endometriosis face several limitations. Researchers typically measure only a few widespread congeners that are selected because of their toxicological activities, including an association with cancer shown in animal models. “So we’re only getting part of the picture,” says Germaine Buck Louis, chief of the Epidemiology Branch at the National Institute of Child Health and Human Development.In a study described in the January 2005 issue of Human Reproduction, Buck’s team measured 62 congeners in 84 women undergoing laparoscopy. Levels of 4 antiestrogenic congeners were 3.77 times higher in women diagnosed with endometriosis than in controls. “We don’t fully understand the role of estrogenic and antiestrogenic PCBs,” she says, but complex interactions of many PCBs as well as other chemicals may be involved in developing endometriosis.Recent advances in PCB detection methods allow more congeners to be measured at lower concentrations. “Women with endometriosis may have low levels of a particular congener not found in [other women],” says Louis. Moreover, breastfeeding reduces PCB levels in women, so women without endometriosis may have lower blood levels because they become pregnant and breastfeed more often. “There’s no ideal comparison group for endometriosis studies,” says Louis, and “there are no easy answers.”FiguresReferencesRelatedDetailsCited By Wang J, Hülck K, Hong S, Atkinson S and Li Q (2011) Accumulation and maternal transfer of polychlorinated biphenyls in Steller Sea Lions ( Eumetopias jubatus ) from Prince William Sound and the Bering Sea, Alaska, Environmental Pollution, 10.1016/j.envpol.2010.09.022, 159:1, (71-77), Online publication date: 1-Jan-2011. Trenck K, Schilling F and Schmidt D (2007) Bioindikation mit WanderfalkenBioindication with peregrine falcons: New results from Baden-Wuerttemberg, Umweltwissenschaften und Schadstoff-Forschung, 10.1065/uwsf2007.03.187, 19:2, (75-82), Online publication date: 1-Apr-2007. Vol. 114, No. 7 July 2006Metrics About Article Metrics Publication History Originally published1 July 2006Published in print1 July 2006 Financial disclosuresPDF download License information EHP is an open-access journal published with support from the National Institute of Environmental Health Sciences, National Institutes of Health. All content is public domain unless otherwise noted. Note to readers with disabilities EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.