Comparaison de plusieurs supports analytiques inertes et biologiquespour apprécier la contamination métallique de la retenue du siteélectronucléaire de Cattenom, France

Abstract

The trace metals Cd, Cu, Pb and Zn were analyzed in the following inert and biological compartments of the ecosystemof the Mirgenbach reservoir: the water, the suspended solids, the settling particulate matter, a bryophyte, a mollusc and three organs of two dominant fish species. This man-made lake receives the warmed waters from the nuclear power plant in Cattenom (Northeastern France). The Lindre pond and an upper section of the Meuse River were chosen as reference sites. All the analyzed substrata showed that the Mirgenbach reservoir is strongly contaminated with copper and moderately with lead and zinc. High burdens of cadmium were only detected in the sediment samples. The trace metals entering the reservoir partition between two different phases: the water column and the sediments. The elevated concentrations observed in the settling particulate matter indicate that a large amount of each metal is eliminated from the water. In the particular case of copper, estimations of fluxes showed that two thirds of the discharged metal were trapped in the sediments. The good agreement of metal detection in the mussel Dreissena polymorpha Pallas and in the moss Fontinalis antipyretica Hedw. emphasizes the suitability of both organisms to be used as biological indicators for water pollution. The two fish species, the roach Rutilus rutilus L. and the perch Perca fluviatilis L., exhibited low metal concentrations in their muscle flesh. Although accumulation occurred in the target tissues, e.g. copper in the liver and lead in the kidney, fish cannot be considered as adequate sentinel organisms. © Gauthier-Villars, 1993.