Persistent organochlorine pollutants in surface sediments and economic shellfish of Minjiang Estuary-Mazu and Xiamen-Jinmen sea areas.

Samples of surface sediment and shellfish were collected from Minjiang Estuary-Mazu and Xiamen-Jinmen sea areas and were analyzed for hexachlorocyclohexanes (HCHs), dichlorodiphenyl-trichlorophenyl (DDT) and its degraded derivatives dichloro-diphenyl-dichloroethane (DDT) and dichloro-dichlorophenyl-ethylene (DDE), and polychlorinated biphenyls (PCBs) by gas chromatography. Concentration ranges of HCHs, DDTs, and PCBs in the sediments were 0.03-0.48, 1.10-14.3, and ND to 0.76 ng/g dw, respectively; those for shellfish samples were ND to 1.5, 21.5-892, dw and ND-3.7 ng/g dw, respectively. The results showed that the concentrations of such oganochlorine compounds (OCs) in the sediments were usually low as compared with other sea areas and estuaries, and the organochlorines were accumulated in marine bivalve mollusks, particularly in oyster. With respect to the concentrations of HCHs, DDTs, and PCBs in the samples of either sediment or shellfish, DDTs were higher than HCHs and PCBs. The concentrations of OCs in shellfish samples varied with the sampling locations and organism species but were generally higher than those in the sediments. The concentration distributions, compositions, and residue levels of these OCs are extensively discussed and evaluated.