High Concentrations Of Polychlorinated Biphenyls Research Articles

Feed Ingredients Mainly Contributing to Polycyclic Aromatic Hydrocarbon and Polychlorinated Biphenyl Residues

Animal nutrition constitutes an important issue for the animal production industry. Products intended for animal feed may contain undesirable substances which could endanger animal health or, because of their presence in livestock products, human health or the environment. In this sense, several incidents related with the presence of persistent organic pollutants, particularly with polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs), have happen in food and feed additives. Simple, fast, quantitative, and economic methods for determining PAHs and PCBs in potentially polluting feed ingredients were developed and evaluated. The methods involved liquid-liquid extraction (LLE), clean-up, and detection by liquid chromatography with fluorescence detection (LC-FD) for PAHs and gas chromatography (GC) coupled to electron capture detection (ECD) for PCBs, using tandem mass spectrometry (MS/MS) as confirmatory technique. The overall method quantification limits range from 0.020– 4.0 μg/Kg for PAHs and from 0.20–0.75 μg/Kg for PCBs, analyte recoveries are between 70 and 105% with relative standard deviations (RSD) lower than 20%. Once the method was optimized, it was applied to 25 feed ingredients considered as potential candidates for feedstuff. As expected, the samples of animal origin as shell powder and fish oil showed the highest PCB concentrations of 56 and 29 ng/g, which are equivalent to toxicological concentrations of 123 and 18 ng WHO-TEQDL-PCBs/Kg, respectively. Opposite results were obtained with PAHs and the highest PAH4 levels were detected alfalfa (47 μg/Kg), calcium phosphate (27 μg/Kg), and palm oil (23 μg/Kg) used as feed ingredients.

Polychlorinated Biphenyl Congeners in River Sediments: Distribution and Source Identification Using Multivariate Factor Analysis

To assess the level of polychlorinated biphenyl (PCB) contamination and identify their sources, surface sediments were collected from selected locations along Nakdong River, Korea, and analyzed for 209 PCB congeners using high-resolution gas chromatography/high-resolution mass spectroscopy. PCB levels ranged from 0.124 to 79.2ng/g dry weight (coplanar PCBs 0.295 to 5720pg/g dry), which were similar to those of three other major rivers (Han, Geum, and Youngsan rivers) in Korea but slightly lower than those in neighboring countries. Regarding homologue composition, tetra-CBs were most abundant in most samples, but some samples with much higher PCBs concentrations had relatively lower proportions of tetra-CBs and higher proportions of penta- to hepta-CBs. To identify the sources of PCBs in sediment samples, principal component analysis/absolute principal component scores (PCA/APCS), positive matrix factorization (PMF), and multiple linear regression (MLR) were used with the congener composition of aroclors (1242, 1248, 1254, and 1260) and the flue gas of waste incinerators (data obtained from a previous article) as source profiles. Results showed that the three models showed similar source apportionments. Most sediment samples with lower PCB concentrations had higher proportions of incineration-derived materials, and some sediment samples with much higher PCB concentrations had higher proportions of aroclor 1260. This occurred because many industrial facilities, such as landfill leachate-treatment facilities, were gathered around sampling points with high PCB concentrations, and high-chlorinated PCBs are more stable in the elution process of landfill leachate than the incineration process. PCB concentrations estimated by APCS, PMF, and MLR were similar to the measured values with coefficients of determination ranging from 0.77 to 0.99.

Organochlorine and Metal Contaminants in Traditional Foods from St. Lawrence Island, Alaska

Marine mammals (bowhead whale, walrus, and various seals) constitute the major component of the diet of the Yupik people of St. Lawrence Island, Alaska. St. Lawrence Island residents have higher serum concentrations of polychlorinated biphenyls (PCB) than in the general U.S. population. In order to determine potential sources, traditional food samples were collected from 2004 to 2009 and analyzed for PCBs, three chlorinated pesticides, and seven heavy metals (mercury, copper, zinc, arsenic, selenium, cadmium, and lead). Concentrations of PCB in rendered oils (193–421 ppb) and blubber (73–317 ppb) from all marine mammal samples were at levels that trigger advisories for severely restricted consumption, using U.S. Environmental Protection Agency (EPA) fish consumption advisories. Concentrations of pesticides were lower, but were still elevated. The highest PCB concentrations were found in polar bear (445 ppb) and the lowest in reindeer adipose tissue (2 ppb). Marine mammal and polar bear meat in general have PCB concentrations that were 1–5% of those in rendered oils or adipose tissue. PCB concentrations in organs were higher than meat. Concentrations of metals in oils and meats from all species were relatively low, but increased levels of mercury, cadmium, copper, and zinc were present in some liver and kidney samples. Mercury and arsenic were found in lipid-rich samples, indicating organometals. These results show that the source of the elevated concentrations of these contaminants in the Yupik population is primarily from consumption of marine mammal blubber and rendered oils.

Effects of hydrodynamics on the distribution of trace persistent organic pollutants and macrobenthic communities in Bohai Bay

In recent years, the rapid economic development along Bohai Bay, has brought out continuous increasing of the pollution loads in the Bohai Sea, especially by the large coastal reclamation project, Tianjin Binhai New Area. In the period of 2007–2009, we collected the sediments of the main rivers, estuaries, intertidal zone, and near-shore area of Bohai Bay, and Macrobenthos associated with the marine sediments to assess the influence of hydrodynamics in the coastal environment on the pattern of trace contaminants and the macrobenthic community. Based on data derived from these samples, the levels of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) in sediments followed the order PAHs > OCPs > PCBs > PBDEs. The higher concentrations of PCBs, OCPs, PAHs and PBDEs were found in the estuarine and near-shore environment of the Dagu Drainage River. The spatial distribution of OCPs was different to that of PCBs due to the direction of the velocity field of Bohai Bay in its old and new topography, and the higher water-solubility of OCPs than that of PCBs. The results of the Pearson correlation and the PCA indicate that the medium diameter (MD) of sediments was the predominant factor influencing the distribution of PCBs and OCPs, most sampling sites were characterized mainly by TOC of sediments and biomass of macrobenthos. The results indicate that the distribution of trace contaminants and macrobenthic community in Bohai Bay are mainly affected by the hydrodynamic conditions.

Marine Food Pollutants as a Risk Factor for Hypoinsulinemia and Type 2 Diabetes

Some persistent environmental chemicals are suspected of causing an increased risk of type 2 diabetes mellitus, a disease particularly common after the age of 70. This concern was examined in a cross-sectional study of elderly subjects from a fishing population with elevated contaminant exposures from seafood species high in the food chain. Clinical examinations of 713 Faroese residents aged 70-74 years (64% of eligible population) included fasting plasma concentrations of glucose and insulin, and glycosylated hemoglobin. Lifetime exposure to persistent environmental chemicals from pilot whale and other traditional food was estimated from a dietary questionnaire and by analysis of blood samples for polychlorinated biphenyls (PCBs) and related food contaminants. Septuagenarians with type 2 diabetes or impaired fasting glycemia tended to have higher PCB concentrations and higher past intake of traditional foods, especially during childhood and adolescence. In nondiabetic subjects, the fasting insulin concentration decreased by 7% (95% CI = -12% to -2%) for each doubling of the PCB concentration after adjustment for sex and body mass index at age 20. Conversely, the fasting glucose concentration increased by 6% (-1% to 13%) for each doubling in PCB. Similar associations were seen in subjects without impaired fasting glycemia, while further adjustment for current body mass index and lipid metabolism parameters attenuated some of the associations. Impaired insulin secretion appears to constitute an important part of the type 2 diabetes pathogenesis associated with exposure to persistent lipophilic food contaminants.

Effects of embryonic exposure to polychlorinated biphenyls on zebrafish (Danio rerio) retinal development

Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that affect embryonic development. The purpose of this study was to examine the effects of embryonic exposure to PCBs on early retinal development in zebrafish, Danio rerio. Zebrafish embryos were immediately exposed to different concentrations (0, 0.125, 0.25, 0.5, 1.0 and 2.0 mg) of PCBs per liter of medium at 28.5 °C. Embryos were assessed at 30, 48, 72 and 96 h post-fertilization (hpf) for changes in embryonic survival rate, development, larval retinal morphology and ultrastructure of the retina. The results show that PCB exposure decreased the survival rate of embryos in a time- and dose-dependent manner. Embryos exposed to the higher concentrations of PCBs (0.5, 1.0 and 2.0 mg l(-1) ) displayed obvious gross morphological deformities. At 72 hpf, the retinal layer development of zebrafish was delayed at higher PCB concentrations (1.0 mg l(-1) ). At 96 hpf, irregularity of photoreceptor cells arrangement and thickening of photoreceptor and ganglionic layers were observed in PCB-treated larvae at concentrations of 0.25-1 mg l(-1) . Ultrastructural examination showed signs of growth inhibition of the photoreceptor outer segment at 0.25-1 mg l(-1) PCB exposure at 72 hpf, as well as the appearance of massive vacuoles and holes inside the outer segments in the PCB exposure group at 96 hpf. These results suggest that embryonic exposure to moderate and high levels of PCBs induced developmental deficits in zebrafish retinas, particularly in photoreceptor cells.

Maternal and early postnatal polychlorinated biphenyl exposure in relation to total serum immunoglobulin concentrations in 6-month-old infants

Animal data indicate that developmental tetrachlorodibenzo-p-dioxin exposure alters immune function; however, the potential immunotoxicity of dioxin-like and non-dioxin-like polychlorinated biphenyls (PCBs) in the developing infant is an understudied area. The aim of the current study is to examine the association between maternal and early postnatal PCB concentrations in relation to total infant serum immunoglobulin concentrations determined at 6-months-of-age. We selected 384 mother-infant pairs participating in a birth cohort study in Eastern Slovakia. PCB concentrations of several congeners were determined in maternal and cord serum samples and in infant serum samples collected at 6-months-of-age using gas chromatography with electron capture detection. Total immunoglobulin (Ig) G, A, and M concentrations were determined by nephelometry, and IgE concentrations were determined by enzyme-linked immunoassay. Linear regression models with adjustment for potential confounding factors were used to estimate the associations between maternal, cord, and 6-month infant PCB concentrations and total serum immunoglobulins. The median maternal serum concentration of PCB-153 was 140 ng/g lipid, ≈10-fold higher than concentrations in childbearing-age women in the United States during the same period. Maternal, cord, or 6-month infant PCB concentrations were not associated with total serum immunoglobulin levels at 6 months, regardless of the timing of PCB exposure, PCB congener, or specific immunoglobulin. In this population, which has high PCB concentrations relative to most populations in the world today, we did not observe any association between maternal and early postnatal PCB concentrations and total immunoglobulin measures of IgG, IgA, IgM, or IgE.

Evidence for Major Emissions of PCBs in the West African Region

In previous studies unexpectedly high air concentrations of polychlorinated biphenyls (PCBs) were observed in ship-based measurements made ∼400 km off parts of the West African coast. To investigate further (i) samples were taken on board the RV Polarstern during a cruise from Germany to South Africa in October-November 2007; (ii) samples were obtained on Cape Verde Island during the same period to monitor airflows from Africa; and (iii) passive samplers were deployed in four West African countries to try to characterize potential sources on land. Results were as follows: on Cape Verde and on the ship air masses came predominantly (∼ 95%) from the African continent; the shipboard Σ29PCB concentrations off West Africa ranged from 10 to 360 pg m(-3) and from 6 to 99 pg m(-3) in Cape Verde; the highest land-based concentrations were observed in Ivory Coast and the Gambia (up to 300 pg m(-3)) and the lowest was observed in Ghana (9 pg m(-3)). Taken together, these and previous studies indicate there are more major emission(s) of PCBs and different source types in parts of West Africa than accounted for in current global atmospheric emissions estimates. Results from the FLEXPART model and PAH measurements show that emission inventories and biomass burning cannot fully explain the high PCB concentrations. Potential sources of the high PCB levels to the African regions are discussed, namely illegal dumping of PCB containing waste with release via volatilization and uncontrolled burning, and the storage and breakup of old ships.

Spatial distribution of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs) in an e-waste dismantling region in Southeast China: Use of apple snail ( Ampullariidae) as a bioindicator

Fengjiang is a large e-waste dismantling site located in southeast China. In this paper, apple snail and soil samples were collected from this e-waste dismantling site and 25 vicinal towns to investigate the contamination status, spatial distributions and congener patterns of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs). Total PCB concentrations in apple snails (3.78–1812 ng g −1 dry weight (dw)) were significant higher than that in soil samples (0.48–90.1 ng g −1 dw). PBDE (excluding BDE 209) concentrations in apple snail and soil samples ranged from 0.09 to 27.7 ng g −1 dw and 0.06 to 31.2 ng g −1 dw, respectively. Concentrations of PCBs and PBDEs in snails and soils correlated negatively with the distance from Fengjiang. Both the concentrations and profiles of the pollutants were significantly correlated ( p < 0.05) between the snail and soil samples, indicating the suitability of apple snail as a reliable bioindicator for PCBs and PBDEs contamination in this region. Relatively high concentrations of PCBs and PBDEs at locations far from e-waste dismantling sites implied that these pollutants have been transported to surrounding regions.

Relationships between occupational history and serum concentrations of organochlorine compounds in exocrine pancreatic cancer

BackgroundPrevious studies investigating associations between occupational history and risk of exocrine pancreatic cancer (EPC) did not use biomarkers of exposure. The only two studies that measured internal concentrations of organochlorine...

Spatial and seasonal variation of polychlorinated biphenyls in Songhua River, China

The spatial and seasonal variation of polychlorinated biphenyls (PCBs) were investigated in water and sediment samples collected from Songhua River, China, from 2007 to 2008. The total concentration of PCB congeners ranged from 1.1 to 14 ng/l in water and 0.26-9.7 ng/g dry weight (dw) in sediment. The results of seasonal variation may suggest an impact to PCB concentration in water from its atmospheric input, the dilution to PCBs concentrations of high stream in summer, and a general trend towards increased volatilization in warmer conditions. From PCBs concentrations comparison between upstream and downstream of industrial urban cities, it was obvious that industrial urban cities reflect an important pollutant source for PCBs in our study, also with the evidences of high concentrations of PCBs occurring in high development industry and residential areas. Meanwhile, the homologue profile of PCBs in Songhua was analyzed, whose comparison with published data indicates that the sources of PCBs accumulated in the sediment may also came from the residue of PCBs production in China. Total five dioxin-like PCBs (CB-77, 81, 105, 114, and 126) and nine (CB-77, 81, 105, 114, 118, 123, 126, 156, and 167) were found in Songhua water and sediment.

Diminished Protection?: Early Childhood PCB Exposure and Reduced Immune Response to Vaccinations

Vol. 118, No. 10 NewsOpen AccessDiminished Protection?: Early Childhood PCB Exposure and Reduced Immune Response to Vaccinations Julia R. BarrettMS, ELS Julia R. Barrett Search for more papers by this author Published:1 October 2010https://doi.org/10.1289/ehp.118-a445aCited by:2AboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit Polychlorinated biphenyls (PCBs) constitute a class of persistent organic pollutants suspected or known to cause adverse health effects. Among these effects are immune system dysfunctions that may hinge on both the magnitude and the timing of PCB exposure. A new study uses the backdrop of routine childhood immunizations to explore the developmental immunotoxicity of PCBs and finds that higher PCB exposure in toddlerhood is associated with reduced antibodies against diphtheria and tetanus later in childhood [EHP118(10):1434–1438; Heilmann et al.].The study took place in the Faroe Islands, midway between the Shetland Islands and Iceland in the North Atlantic, and involved 587 children from a 1999–2001 birth cohort. A traditional diet including pilot whale blubber, consumed by some but not all Faroese, creates a wide range of PCB exposures for this population. To assess the transfer of PCB from a mother to her child, maternal blood samples were taken in week 32 of pregnancy. The mothers also provided milk samples at 4–5 days after birth.Based on the routine vaccination schedule, children were immunized against diphtheria and tetanus at 3, 5, and 12 months, with a booster at 5 years. Approximately one-fifth of the children had blood drawn at 18 months, and blood samples were drawn before the booster shots at age 5 years for 532 children and 7 years for 464 children. PCB concentrations were assessed in blood and milk samples, and diphtheria and tetanus antibodies were measured in children’s blood at ages 5 and 7.Analysis revealed inverse relationships between PCB concentrations at different time points and antibody concentrations. The associations between concomitant measurements were not significant at either 5 or 7 years. However, higher PCB concentrations in mother’s milk samples collected after birth and in children’s blood samples at 18 months were clearly associated with lower levels of diphtheria antibodies in the children at age 5. When PCB concentrations at 18 months were estimated for the entire cohort based on known levels at birth and at 5 years paired with breastfeeding duration and PCB concentrations measured in blood samples from a subset of children at 18 months, this relationship became even stronger for diphtheria at both 5 and 7 years, and a similar relationship for tetanus antibody concentration at age 7 became significant.The authors point out that early-life PCB exposure may increase the risk of incomplete protection against diphtheria and possibly tetanus even if a child receives a full schedule of vaccinations. But the implications of the results extend beyond vaccination because diphtheria and tetanus immune response reflects the efficacy of the immune system against a broad array of infections.FiguresReferencesRelatedDetailsCited by Cao J, Xu X, Hylkema M, Zeng E, Sly P, Suk W, Bergman Å and Huo X (2016) Early-life Exposure to Widespread Environmental Toxicants and Health Risk: A Focus on the Immune and Respiratory Systems, Annals of Global Health, 10.1016/j.aogh.2016.01.023, 82:1, (119-131), Online publication date: 1-Jan-2016. Lin Y, Pessah I and Puschner B (2013) Simultaneous determination of polybrominated diphenyl ethers and polychlorinated biphenyls by gas chromatography–tandem mass spectrometry in human serum and plasma, Talanta, 10.1016/j.talanta.2013.04.001, 113, (41-48), Online publication date: 1-Sep-2013. Vol. 118, No. 10 October 2010Metrics About Article Metrics Publication History Originally published1 October 2010Published in print1 October 2010 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.

Major Pollutants in Soils of Abandoned Agricultural Land Contaminated by e-Waste Activities in Hong Kong

Polycyclic aromatic hydrocarbon (PAH), polychlorinated biphenyl (PCB), polybrominated diphenyl ether (PBDE) compounds and five heavy metals (cadmium, copper, chromium, lead, and zinc) were determined in soil samples collected from six sites of abandoned agricultural land affected by electronic-waste: e-waste dismantling workshop [EW (DW)], e-waste open burning site [EW (OBS)], e-waste storage [EW (S)], and agricultural (A) in the New Territories, Hong Kong. Persistent organic pollutants (POPs) and heavy metals were detected in all soil samples. EW (DW) contained the highest concentrations of PAHs, Cr, Cu, and Zn, whereas EW (OBS) had the highest concentrations of PCBs, PBDEs, Cd, and Pb. PAH at EW (DW) and EW (OBS) and PCB concentrations at EW (OBS) exceeded the target values of the New Dutch list, whereas Cd, Cu, Cr, Pb, and Zn levels exceeded the Chinese legislation for the protection of agricultural production and safeguarding of human health, by 3-11 times at EW (OBS) and 5-8 times at EW (DW). Lead at EW (OBS) and EW (DW) and Cr at EW (DW) greatly exceeded the Canadian Soil Quality Guidelines by 46 and 20 times and 27 times, respectively. Concentrations of POPs and heavy metals at EW (DW) and EW (OBS) were significantly higher than at EW (S) and A. It was concluded that e-waste activities led to increases of toxic chemicals at these abandoned agricultural land, which would hinder the redevelopment of the land.

Organic pollutants in microplastics from two beaches of the Portuguese coast

Microplastics pose a threat to coastal environments due to their capacity to adsorb persistent organic pollutants (POPs). These particles (less than 5mm in size) are potentially dangerous to marine species due to magnification risk over the food chain. Samples were collected from two Portuguese beaches and sorted in four classes to relate the adsorption capacity of pollutants with color and age. Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and DDTs were analysed on pellets through gas chromatography mass spectrometry (GC-MS), and types of plastic were identified using Fourier transformed infra-red spectroscopy (micro-FTIR). Microplastics were mostly polyethylene and polypropylene. Regarding sizes, some fibres ranged from 1 to 5μm in diameter and were 500μm in length. The majority of samples collected had sizes above 200μm. Black pellets, unlike aged pellets, had the highest concentrations of POPs except for PAHs in Fonte da Telha beach. PAHs with higher concentrations were pyrene, phenantrene, chrysene and fluoranthene. Higher concentrations of PCBs were found for congeners 18, 31, 138 and 187. Further investigation is necessary to understand the relationship between plastic degradation and adsorption for different pollutants.

High concentrations of persistent organic pollutants including PCBs, DDT, PBDEs and PFOS in little brown bats with white-nose syndrome in New York, USA

White-nose syndrome (WNS) is a condition associated with white fungal growth on ears, wings, and nose of hibernating bats; this condition has recently resulted in high bat mortality in the northeastern United States. Nevertheless, the pathogenesis of morbidity and mortality are still unknown. Elevated exposure to toxic contaminants could be a contributing factor via the consequent immunosuppression and endocrine disruption. In this study, diseased little brown bats ( Myotis lucifugus) were collected from several hibernacula in eastern New York State in 2008. Fat tissues of bats were analyzed for polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), and organochlorine pesticides (OCPs; DDT, chlordanes, HCB, and HCH), and liver was analyzed for perfluorinated compounds (PFCs). A reference population of little brown bats, not affected by WNS, was also collected from a cave in Kentucky for the analysis of trace organic contaminants. Concentration of PCBs in fat tissues of bats from New York ranged from 1900 ng g −1 to 35 000 ng g −1, lipid wt, with the highest concentrations found in bats collected from caves in Albany County. High concentrations of PCBs were also found in bats from Kentucky (17 100–18 400 ng g −1, lipid wt). Total PBDE concentrations in fat tissues ranged from 520 ng g −1 to 10 900 ng g −1, lipid wt, in bats from New York and from 4300 ng g −1 to 13 000 ng g −1, lipid wt, in bats from Kentucky. High concentrations of DDT (26 900 ng g −1, lipid wt), chlordanes (6350 ng g −1, lipid wt), and HCB (260 ng g −1, lipid wt) were found in bats from New York. Concentrations of hexabromobiphenyl congener 153 (PBB 153) in bats from New York ranged from 8.6 ng g −1 to 12 4000 ng g −1, lipid wt. Concentrations of PFCs were on the order of a few tens to a few hundreds of nanograms per gram liver, on a wet weight basis. Overall, high concentrations of PCBs, PBDEs, DDT, and chlordanes were found in fat tissues of diseased bats from New York, although the concentrations in bats from non-diseased, reference population, from Kentucky were also high.

Levels of Polychlorinated Biphenyls in Human Adipose Tissue Samples from Southeast China

This paper presents a comprehensive study of polychlorinated biphenyl (PCB) levels and homologue profiles in human adipose tissues among residents of Southeast China. A large number of samples (n = 303) were selected for a number of PCB congeners (n = 62) which were analyzed by highly sensitive gas chromatography-tandem mass spectrometry (GC-MS/MS). The total mean PCB concentrations were 27.2 microg/kg fat (n = 159) in Anhui Province and 17.2 microg/kg fat (n = 144) in Jiangsu Province. A significant correlation was observed between age and PCB levels but not found between gender and PCB levels. The relationship between the environmental contaminant levels and the PCB concentration in adipose tissue was also investigated. It was found that the higher PCB concentrations in human adipose tissue were associated with the higher environmental PCB levels in the corresponding regions. The PCB homologue profiles of the human adipose tissue in China are different from those in the world, similarly to the different PCB homologue pattern between Chinese and global soils. The concept of the urban fractionation effect in the environment may be applicable to explain the PCB homologue profiles and PCB levels in the human adipose tissues collected from different provinces in China. The data presented in this study can provide useful information on human exposures to PCBs in the general population of Southeast China.

Composition, distribution, and potential toxicity of organochlorine mixtures in bed sediments of streams

Mixtures of organochlorine compounds have the potential for additive or interactive toxicity to organisms exposed in the stream. This study uses a variety of methods to identify mixtures and a modified concentration-addition approach to estimate their potential toxicity at 845 stream sites across the United States sampled between 1992 and 2001 for organochlorine pesticides and polychlorinated biphenyls (PCBs) in bed sediment. Principal-component (PC) analysis identified five PCs that account for 77% of the total variance in 14 organochlorine compounds in the original dataset. The five PCs represent: (1) chlordane-related compounds and dieldrin; (2) p,p′-DDT and its degradates; (3) o,p′-DDT and its degradates; (4) the pesticide degradates oxychlordane and heptachlor epoxide; and (5) PCBs. The PC analysis grouped compounds that have similar chemical structure (such as parent compound and degradate), common origin (in the same technical pesticide mixture), and(or) similar relation of concentrations to land use. For example, the highest concentrations of chlordane compounds and dieldrin occurred at urban sites, reflecting past use of parent pesticides for termite control. Two approaches to characterizing mixtures—PC-based mixtures and unique mixtures—were applied to all 299 samples with a detection of two or more organochlorine compounds. PC-based mixtures are defined by the presence (in the sample) of one or more compounds associated with that PC. Unique mixtures are defined as a specific combination of two or more compounds detected in a sample, regardless of how many other compounds were also detected in that sample. The simplest PC-based mixtures (containing compounds from 1 or 2 PCs) commonly occurred in a variety of land use settings. Complex mixtures (containing compounds from 3 or more PCs) were most common in samples from urban and mixed/urban sites, especially in the Northeast, reflecting high concentrations of multiple chlordane, dieldrin, DDT-related compounds, and(or) PCBs. The most commonly occurring unique mixture ( p,p′-DDE, p,p′-DDD) occurred in both simple and complex PC-based mixtures, and at both urban and agricultural sites. Mean Probable Effect Concentration Quotients (PEC-Q) values, which estimate the potential toxicity of organochlorine contaminant mixtures, were highest for complex mixtures. Mean PEC-Q values were highest for urban sites in the Northeast, followed by mixed/urban sites in the Northeast and agricultural sites in cotton growing areas. These results demonstrate that the PEC-Q approach can be used in combination with PC-based and unique mixture analyses to relate potential aquatic toxicity of contaminant mixtures to mixture complexity, land use, and other surrogates for contaminant sources.

Bioaccumulation markers and biochemical responses in European sea bass ( Dicentrarchus labrax) raised under different environmental conditions

Site- and season-specific biochemical responses and bioaccumulations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were analysed in tissues from sea bass raised under four different environmental conditions and sampled in April and July. Samples were analysed for condition factor (CF), liver somatic index (LSI), glutathione S-transferase (GST) activity, and glycogen and lactate contents. Results showed the presence of PCBs and DDTs, with site- and season-specific variations in its concentrations. CFs did not differ significantly, while LSIs in samples from two of the four sites decreased between April and July. GST activities were lower in samples with higher concentrations of PCBs and DDTs. Lactate and glycogen contents were influenced to a greater extent by the season than by levels of contamination. The study demonstrated that farming methods could play a crucial role in both health status and bioaccumulation of OC compounds in farmed sea bass.

PCBs and DDE in Tree Swallow (Tachycineta bicolor) Eggs and Nestlings from an Estuarine PCB Superfund Site, New Bedford Harbor, MA, U.S.A.

While breeding tree swallows (Tachycineta bicolor) have been used as biomonitors for freshwater sites, we report the first use of this species to assess contaminant bioaccumulation from estuarine breeding grounds into these aerial insectivores. Eggs and nestlings were collected from nest boxes in a polychlorinated biphenyl (PCB) contaminated estuary, the New Bedford Harbor Superfund site (NBH, Massachusetts, USA), and a reference salt marsh, Fox Hill (FH, Jamestown, Rhode Island, USA). Sediments, eggs, and nestlings were compared on a ng g(-1) wet weight basis for total PCBs and DDE (1,1-bis-(4-chlorophenyl)-2,2-dichloroethene), metabolite of DDT (1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane). NBH samples contained high concentrations of PCBs compared to FH for sediment (36,500 and 0.2), eggs (11,200 and 323), and nestlings (16,800 and 26). PCB homologue patterns linked tree swallow contamination to NBH sediment. NBH samples were also contaminated with DDE compared to FH for sediment (207 and 0.9) and nestlings (235 and 30) but not for eggs (526 and 488), suggesting both NBH and nonbreeding ground sources for DDE. The relationships between sediment and tree swallow egg and nestling PCBs were similar to those reported for freshwater sites. Like some highly contaminated freshwater sites, NBH PCB bioaccumulation had little apparent effect on reproductive success.

Polycyclic aromatic hydrocarbons, polychlorinated biphenyls and organochlorine pesticides in urban air of Konya, Turkey

Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in urban air samples of Konya, Turkey between August 2006 and May 2007. The concentrations of pollutants in both the gas and particulate phase were separately analysed. The average total (gas + particulate) concentrations of PAHs, PCBs and OCPs were determined as 206 ng m − 3 , 0.106 ng m − 3 , 4.78 ng m − 3 respectively. All of the investigated target compounds were dominantly found in the gas phase except OCPs. Higher air concentrations of PAHs were found at winter season while the highest concentrations of PCBs were determined in September. The highest OCPs were detected in October and in March. In urban air of Konya, PCB 28 and PCB 52 congeners represent 46% and 35% of total PCBs while Phenanthrene, Fluoranthene, Pyrene accounted for 29%, 13%, 10% of total PAHs. HCH compounds (α + β + γ + δ-HCH), total DDTs ( p, p′-DDE, p, p′-DDD, p, p′-DDT), Endosulfan compounds (Endosulfan I, Endosulfan II, Endosulfan sulfate) were dominantly determined as 30%, 21%, 20% of total OCPs respectively. Considering the relation between these compounds with temperature, there was no significant correlation observed. Despite banned/restricted use in Turkey, some OCPs were determined in urban air. These results demonstrated that they are either illegally being used in the course of agricultural activity and gardens in Konya or they are residues of past use in environment. According to these results, it can be suggested that Konya is an actively contributing region to persistent organic pollutants in Turkey.