Comparative study of toxicity, uptake and distribution of cadmium and mercury in the sea water adapted eel Anguilla anguilla

There is no evidence whether Cd and Hg are biologically essential but their toxicity for organisms is well known (FRIBERG et al., 1974; FRIBERG and VOSTAL, 1972). One of their main properties regarding biological effects is their ability to bind to organic substances, principally to sulfhydryl groups. Data about Cd and Hg toxicity for fish are rather extensive (DOUDOROFF and KATZ, 1953; BOEETIUS, 1960; BALL, 1967; EISLER, 1971; PICKERING and GAST, 1972). Some informations describing the distribution of these metals in tissues of experimentally intoxicated fishes are also available (BAECKSTROEM, 1967; MIETTINEN et al. 1972; BOUQUEGNEAU, 1973; EISLER, 1974; ROWE and MASSARO, 1974). However no comparative study of the effects generated by Cd and Hg on the same species of fish has been reported. This is the aim of the present paper. In the experiments, Cd and Hg are directly added to sea water. Data seem to indicate that for both metals, uptake from water would be much more important than from food (HANNERZ, 1968; JERNELOEV and LANDNER, 1969; BOUQUEGNEAU et al., 1976).