HEAVY-METALS (HG, CD, CU, PB, ZN) IN LIVER AND MUSCLE-TISSUE OF FRESHWATER PERCH (PERCA-FLUVIATILIS) OF THE LAKE BIEL AND THE WALENSEE

Liver and muscle tissue from fish caught between 1973 and 1975 in two Swiss lakes, namely the Lake of Biel and the Walensee, were analyzed for the heavy metals Hg, Cd, Cu, Pb and Zn. The research project was carried out within the framework of an international OECD programme. The mean of the heavy metal concentrations in mg/kg undried material lay within the following ranges:[Figure not available: see fulltext.] The comparison of metal concentrations in fish originating from the two lakes revealed for the Lake of Biel higher Hg values throughout and higher Cu and Zn values in the livers, whereas for the Walensee the Cd values were found to be higher in the livers. The Pb concentrations did not differ significantly. With regard to the examined organs (livers and muscles) the comparison showed higher Hg concentrations in the muscles than in the livers. The Cd, Cu, Pb and Zn concentrations, however, were found to be higher in the livers. Not a sigle fish sample exceeded Switzerland's admissible tolerance level for Hg, namely 0.5 mg/kg in fish meat. © 1979 Birkhäuser Verlag.