CONCENTRATIONS AND SPATIAL VARIATIONS OF CYCLODIENES AND OTHER ORGANOCHLORINES IN HERRING AND PERCH FROM THE BALTIC-SEA

Herring (Clupea harengus) and perch (Perca fluviatilis) were collected in the northern and southern Baltic Sea and analyzed for the presence of the cyclodiene pesticides chlordane (CHL), heptachlor, aldrin, die ldrin, endrin, isodrin, endosulfan and mirex, as well as other organoc hlorine contaminants, hexachlorocyclohexanes (HCHs), DDTs, hexachlorob enzene (HCBz) and polychlorinated biphenyls (PCBs) in order to investi gate concentrations, accumulation and differences in geographical dist ribution. In the northern part of the Baltic Sea, Gulf of Bothnia, her ring were collected at two pelagic stations, one in the Bothnian Bay ( BB) and the other in the Bothnian Sea (BS), respectively; perch were c ollected at four coastal locations along the Swedish coast. All these locations were selected to represent background areas except one in th e vicinity of an industrialised and contaminated area. Both specimens were also caught in the southern part of the Baltic Sea, in the Gulf o f Gdansk (GG), Poland, a potentially highly polluted area. From the ei ght cyclodiene pesticides analyzed, three were detected in herring and perch samples, including 12 different CHL-related compounds, dieldrin and mirex. To our knowledge, it is the first time that mirex has been detected in samples from the Baltic Sea. Neither heptachlor, aldrin, endrin, isodrin nor endosulfan were found. However, HCHs, DDTs, HCBz a nd PCBs were found in every sample investigated, and the concentration s ranged e.g. for the cyclodiene chemicals dieldrin and CHL-related co mpounds from 30 to 170 ng/g lipid and for PCBs from 360 to 5400 ng/g l ipid, both fish species included. Differences in contamination burden between the sites can be seen, e.g. for herring the BE and GG locals w ere similar, and generally lower than BS for all chemicals except that of DDT where GG was the highest. For the perch samples the industrial ised location had markedly higher concentrations of HCBz and PCBs than the other locations. This species also identifies GG as the most DDT contaminated site among the three studied areas. (C) 1998 Elsevier Sci ence B.V.