LEAD (PB) IN ARCTIC CHAR (SALVELINUS-ALPINUS) FROM OLIGOTROPHIC ALPINE LAKES - GILLS VERSUS DIGESTIVE-TRACT

We studied Arctic char (Salvelinus alpinus) from two oligotropic high mountain lakes in Northern Tyrol, Austria, that differed in pH (5.4 an d 7.1) and alkalinity (1.3 and 100.3 mu eq L-1). Concentrations of Pb in gills, liver, kidney, gut and contents of stomach and gut were inve stigated during winter and summer to elucidate pathways for Pb uptake in these fish. Our study illustrates ratios of Pb concentrations of gi lls to stomach or gills to intestine (G/S and G/l ratios) to be a valu able tool for evaluating the relative contributions of different pathw ays of metal uptake in fish. In both sampling periods (winter, summer) the gills appear to represent a major route pf Pb uptake in fish from low alkalinity lakes. However, during the ice-covered period the diet becomes an increasingly important additional source of Pb contaminati on.