THE BIOACCUMULATION PATTERN OF ORGANOCHLORINE RESIDUES IN LANICE CONCHILEGA (POLYCHAETA) AND ITS GEOGRAPHICAL VARIATION BETWEEN THE ENGLISH-CHANNEL AND THE GERMAN BIGHT

PCBs, p,p'-DDE, HCB, alpha-HCH and gamma-HCH were analysed in Lanice c onchilega from the French, Dutch and German coasts. The annelid exhibi ted a species-specific PCB pattern. It showed lower and higher chlorin ated congeners in more balanced quantities than the polychaete Nereis diversicolor and also the bivalve Mytilus galloprovincialis used in th e French mussel watch programme RNO. The PCB pattern in L. conchilega was influenced by the geographical location, probably by changes of th e environmental PCB composition from SW to NE. Riverine influences cou ld be distinguished from regional ones. Contributions of higher chlori nated PCB congeners increasing from western to eastern river-related p ositions are explained by fractionation of PCBs during atmospheric tra nsport. Concentrations of PCBs and p,p'-DDE in L. conchilega based on extractable organic matter were highest in the Seine Bay indicating a substantial input of these pollutants by the river Seine. No enhanced PCB and p,p'-DDE values were measured in the German Eight. Levels of g amma-HCH and ratios of gamma-HCH/alpha-HCH were elevated near the mout hs of Rance and Seine, which drain areas of intensive agriculture with apparent lindane application. Balanced levels of HCB point to fast at mospheric transport and homogenous deposition of this compound into th e sea. - (C) 1998 Elsevier Science Ltd. All rights reserved.