ORGANOCHLORINE COMPOUNDS IN MARINE ORGANISMS FROM THE INTERNATIONAL NORTH-SEA INCINERATION AREA

Samples were taken in January and May 1988, May 1989 and in January 19 90 to analyse organochlorine residues in organisms from an incineratio n area northwest of the Dutch coast, which had been active since 1979, and from reference areas in its vicinity. The samples consisted of da b (Limanda limanda), whiting (Merlangius merlangus) and the benthic or ganisms hermit crab (Pagurus bernhardus), swimming crab (Linocarcinus holsatus), whelk (Buccinum undatum), helmet crab (Corystes cassivelaun us), sea mouse (Aphrodite aculeata) and sea urchin (Psammechinus milia ris). Tissues of these organisms were analysed using capillary gas chr omatography. The predominant residues were congeners of polychlorinate d biphenyls (PCBs) and the second largest proportion was represented b y the sum of p,p'-DDT and its metabolites. Concentrations of DDT were below the detection limit. Furthermore, residues of the following subs tances were found: pentachlorobenzene (QCB, formerly PeCB), hexachloro benzene (HCB), octachlorostyrene (OCS) and isomers of hexachlorocycloh exane (alpha-HCH and gamma-HCH = lindane). Elevated concentrations of OCS from the incineration area were found in dab and benthic organisms in 1988, 1989 and 1990, and also in whiting in 1989. When comparisons were made throughout the North Sea, significantly elevated concentrat ions of OCS were detected only in the livers of dab from the incinerat ion area. Three of the five invertebrate species from the 1988 samplin g showed significantly elevated concentrations of HCB. In 1989 contami nation of HCB in benthic organisms, dab and whiting in the incineratio n area was significantly higher compared with the reference area. Regi onal differences for HCB in organisms were less consistent than for OC S, which was regularly found in higher concentrations in organisms fro m the incineration area compared with those from neighbouring stations . It is therefore discussed whether elevated levels of OCS in organism s from the North Sea incineration area can be taken as an indication o f incomplete combustion resulting in the accumulation of chlorinated h ydrocarbons in marine organisms. The incineration was terminated in Fe bruary 1991.