Bioaccumulation and human health risks of OCPs and PCBs in freshwater products of Northeast China.

The levels and spatial distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in freshwater products from Northeast China were investigated by gas chromatography coupled to isotope dilution high-resolution mass spectrometry. All samples were on-spot sampled from main production regions of freshwater products in Northeast China, and these samples were used to systematically assess the potential health risks of OCPs and PCBs associated with consumption of these fishery products. Dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexane (HCHs), hexachlorobenzene (HCB) and PCBs were the major pollutants with 100% detection rates, and their levels ranged from 0.086 to 58, 0.038-3.3, 0.093-4.5 and 0.032-1.4 ng g wet weight, respectively. The estimated dietary intakes of these contaminants were all below their corresponding acceptable daily intakes. Significant regional differences in the levels of OCPs and PCBs (P ≦ 0.001) were found in samples from Liaoning and Inner Mongolia. The results showed that the concentrations of targeted contaminants in aquatic products had species-specific characteristics, and the levels of targeted pollutants in Oncorhynchus mykiss and Eriocheir sienesis were significantly higher than those in other aquatic product species. Advisories on ten species of aquatic products suggested that consumption of Eriocheir sinensis, Oncorhynchus mykiss and Cyprinus carpio at a rate exceeding 15 meals per month would pose a cancer risk. A health risk assessment indicated that exposure to these pollutants through freshwater products consumption would cause a non-ignorable potential carcinogenic risk to humans.