[Regional and recent trends in the chlorinated hydrocarbon levels in eels from Berlin waters]

During the five year period from early 1982 to 1986, we engaged in research concerning the chlorinated hydrocarbon content of eels (Anguilla anguilla L.) in the limnic water ecosystem of Berlin (West). The total count of analytical samples, taken at 11 different sampling points, comprised 370 samples, divided up into 41 collectives. Each fish was checked individually for the patterns of contamination with chlorinated hydrocarbons, especially DDT-, BHC-, and PCB-related compounds. The various areas of the Berlin water system develop different particularities as regards pollution. The northern part, consisting mainly of the Tegeler See and the Niederneuendorfer See above the Spree river junction, is in near-neutral condition as shown by rather low levels of chlorinated hydrocarbons in the eels. The Teltowkanal, as it is heavily affected by industrial and urban wastewater, shows considerable contamination of its fish population. Main pollutants are the BHC-isomers, including delta-BHC and the DDT-metabolites 4.4-DDD and 4.4-DDE, as well as higher and lower chlorinated biphenyls (PCB). The lower part of the Havel river, a lake system represented in this study by the fishing stations Stössensee, Pichelsdorfer Gemünd, Schwanenwerder and Pfaueninsel, is limnologically a changing zone characterized by the influx of Spree and Havel rivers and in part by the Teltowkanal, which is reflected in the composition of the organochlorine contamination as well. Three main fishing stations were chosen to represent typical conditions of the ecosystem (Niederneuendorfer See, Pfaueninsel, Teltowkanal) and the trends of concentration of organochlorines in eels were monitored.(ABSTRACT TRUNCATED AT 250 WORDS)