Residues, Sources And Ecological Risk Of Organochlorine Pesticides In Economic Seafoods Of Ningbo And Zhoushan Islands

The organochlorine pesticides (OCPs), including hexachlorocyclohexanes(HCHs) and dichlorodiphenyl trichloroethanes (DDTs) are typical persistent organicpollutants (POPs). They are of worldwide concerning owing to their environmentalpersistence, long-distance transport properities, trend in bioaccumulation through thefood chain and adverse effects on human and other animals.In this study, concentrations of OCPs in ten kinds of economic seafoods(including fve fsh and five mollusk species) collected from the local markets inNingbo City and Zhoushan islands were measured. Then, the possible origins of theOCPs in seafoods were analyzed based on the compositional and metaboliccharacteristics. Moreover, bioaccumulation and ecological risk of OCPs in fishes andmollusks were discussed. This study is propitious for OCPs pollution control andmanagement, and has great significance for protecting human health and safety. Themain conclusions in the study are as follows:(1) The concentrations of OCPs measured by GC-μECD were ranged from3.41to45.65ng/g wet weight (wt), with a mean value of22.76ng/g wet wt. Theconcentrations of OCPs in mackerel (Pneumatophorus japonicus) were all highest insix sites, while the ones in Bullacta (Bullacta exarata) were lowest in all samplingsites but Zhenhai and Putuo.(2) OCPs in fishes were relatively greater than the ones in mollusks and theconcentrations of DDTs were obviously greater than those of HCHs.(3) The-HCH/γ-HCH ratios and the predominance of β-HCH and γ-HCH bothimplied a cocktail input pattern of technical HCH and lindane. DDTs in fshes and mollusks mainly originated from the past agricultural usage in the study area, whilesporadic sources of DDTs may attribute to the current use of DDTs in certain placesnear Beilun and Dinghai.(4) Obvious bioconcentration and biomagnification of OCPs in fishes andmollusks is subsistent for the studied places. OCPs concentrations show significantlypositive correlation with the fat ratios.(5) EDI estimate showed that it is safe to consume fishes and mollusks fromNingbo and Zhoushan islands in terms of the effects of OCPs at present.