Organochlorine pesticides (HCHs and DDTs) in soils along the north coastal areas of the Bohai Sea, China

Abstract

A systematic survey of organochlorine pesticides (OCPs) including hexachlorocyclohexane isomers (-HCH, -HCH, -HCH, -HCH and sigma HCH) and dichlorodiphenyltrichloroethane metabolites (p,p'-DDT, p,p'-DDE, o,p'-DDT, p,p'-DDD and Sigma DDT) in soils along the north coastal areas of the Bohai Sea, China, has been lacking. In this study, 31 representative surface soil samples were collected along the north coastal and riverine areas of the Bohai Sea to characterise the potential for adverse effects of Sigma HCH, Sigma DDT and their individual isomers and transformation products. Concentrations of sigma HCH and sigma DDT in soils ranged from less than the limit of detection (LOD) to 3.0x101ng center dot g-1dw (mean: 3.5ng center dot g-1dw) andLOD to 2.6x102ng center dot g-1dw (mean: 1.7x101ng center dot g-1dw), respectively. Compared with studies of OCPs in soils from other locations, concentrations of HCHs and DDTs observed in this study were moderate. Concentrations of OCPs observed in soils were generally less than proposed reference values. HCH residues were a mixture of historical technical HCH and current lindane sources. The pattern of DDTs was consistent with historical releases of technical DDTs. Selected soil physicochemical properties did not explain the sorption and/or partitioning of HCHs or DDTs.