• High concentrations of PCBs were found at locations near Jinja Municipality.• The PCB and HCH levels were low to moderate compared to other locations worldwide.• The fish from the Napoleon Gulf was fit for consumption in regard to PCBs and HCHs.• The ratios of α-/γ-HCH were low suggesting past input of lindane. a b s t r a c t a r t i c l e i n f o Polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs) were analyzed in surface sediments (b30 cm depth) and two fish species: Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus). The samples were collected from the Napoleon Gulf on the northern shore of Lake Victoria. The analysis was done using a gas chromatograph (GC) coupled to a high resolution mass spectrometer for PCBs and a GC equipped with an electron capture detector for HCHs. Total (Σ) PCBs in the muscles of fish varied widely with mean values ranging from 41 to 670 pg g −1 lipid weight (lw). The PCB levels in L. niloticus were significantly greater than those in O. niloticus. The large variability observed in the data was attributed to differences in feeding habits and trophic levels. While O. niloticus is a filter-eating fish species feeding mainly on phytoplankton and zooplankton, L. niloticus have predatory feeding behaviors and prefer a diet of live fish and, therefore, are more prone to bioaccumulate contaminants. The mean PCB concentrations in the sediments varied from 362 to 848 pg g −1 dry weight. Variations in PCB levels were observed from one study site to another, this was attributed to the nature and particle size of the sediments. HCH isomers were detected in fish at mean concentrations of up to 45,900 pg g −1 lw. The PCB and HCH concentrations were lower than those from previous studies elsewhere in literature and were below the maximum residue limits set by the European Commission and FAO/WHO Codex Alimentarius Commission, implying that the fish was fit for human consumption.

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Polychlorinated naphthalene (PCN) concentrations in the soil at an e-waste recycling area in Guiyu, China, were measured and the associated human cancer risk due to e-waste-related exposures was investigated. We quantified PCNs in the agricultural soil and used these concentrations with predictive equations to calculate theoretical concentrations in outdoor air. We then calculated theoretical concentrations in indoor air using an attenuation factor and in the local diet using previously published models for contaminant uptake in plants and fruits. Potential human cancer risks of PCNs were assessed for multiple exposure pathways, including soil ingestion, inhalation, dermal contact, and dietary ingestion. Our calculations indicated that local residents had a high cancer risk from exposure to PCNs and that the diet was the primary pathway of PCN exposure, followed by dermal contact as the secondary pathway. We next repeated the risk assessment using concentrations for other carcinogenic contaminants reported in the literature at the same site. We found that polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) and PCNs caused the highest potential cancer risks to the residents, followed by polychlorinated biphenyls (PCBs). The relative importance of different exposure pathways depended on the physicochemical properties of specific chemicals.

a Eight aquatic biota species were collected from an e-waste dismantling area in East China to investigate bioconcentration and trophic transfer of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-pdioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The mean concentrations of PCBs varied widely from 6.01 Â 10 4 to 2.27 Â 10 6 pg per g dry weight (dw). The P 25 PCB concentrations in eels were significantly higher than those in other species. The levels of PCDD/Fs changed from 8.13 pg per g dw in toads to 617 pg per g dw in stone snails. World Health Organization-toxic equivalents (WHO 2005 -TEQs) ranged from 2.57 to 2352 pg WHO-TEQ per g dw with a geometric mean value of 64.7 pg WHO-TEQ per g dw, which greatly exceeded the maximum levels of 4 pg per g ww set by the European Commission. The log-transferred bioconcentration factors (BCFs) of 25 PCB congeners ranged from 1.0 to 6.6, with the highest value for CB-205 in crucian carp and the lowest value for CB-11 in frog. A parabolic correlation was observed between log BCF and log K ow (R 2 ¼ 0.53, p < 0.001), where the maximum value occurred at a log K ow of approximately 7. A similar correlation was also found in the plot of log BCF against the number of chlorine atoms of PCBs (R 2 ¼ 0.57, p < 0.001), indicating that mediumhalogenated congeners of PCBs are more easily accumulated by aquatic biota species. There were no significant correlations between the log-transferred concentrations and trophic levels of aquatic species, suggesting that trophic magnification for PCBs and PCDD/Fs was not observed in this study. Environmental impactE-waste dismantling regions have been the subject of great concern in recent years due to the serious environmental contamination associated with e-waste dismantling activities. As a notorious e-waste recycling area in East China, Taizhou has been a hot spot for persistent organic pollutant (POP) research. The present study was conducted to investigate the bioconcentration and trophic transfer tendencies of PCBs and PCDD/Fs in various aquatic biota species in this ewaste area. The high concentrations of POPs in these species reected the lasting impact of e-waste recycling activities on the local environment over more than three decades. Bioconcentration of PCBs was ubiquitously observed in all the species, and signicant parabolic relationships were found between log BCFs and the number of chlorine atoms of PCB congeners as well as their log K ow s. The present results provided important information about the bioaccumulation tendency of POPs in aquatic biota species.

a b s t r a c tAntarctica is considered as a final sink of many persistent organic pollutants (POPs). This work aims to investigate the levels, distributions and potential sources of organochlorine pesticides (OCPs) with HRGC/ HRMS technique. Twenty-three OCPs were measured in various environmental matrices from King George Island, west Antarctica. The total concentrations (S 23 OCPs) were at quite low levels, ranging 93.6 e1260 pg g À1 dry weight (dw) in soil and sediment, 223e1053 pg g À1 dw in moss and 373e812 pg g À1 dw in lichen. Hexachlorobenzene (HCB), dichloro-diphenyl-trichloroethane (DDT) and its metabolites (especially p,p 0 -DDE) and hexachlorocyclohexanes (HCHs) were the main contaminants in all samples.Lower a-HCH/g-HCH and higher p,p 0 -DDE/p,p 0 -DDT ratios compared with the technical products indicated long-range atmospheric transport (LRAT) of recent lindane and aged technical DDT. Significant dependence of many OCPs concentrations on total organic carbon (TOC) was observed. Apart from LRAT, local biotic activities could also contribute and influence the spatial distribution of the contaminants.