Uptake of cadmium by eggs and alevins of Atlantic salmon (Salmo salar) as influenced by acidic conditions.

Abstract

The toxicity of Cd to salmonid eggs and alevins, its uptake by them and distribution in them have been the subject of several studies. In a study of Zn absorption onto the salmoid chorion, it was suggested that the Zn/sup + +/ ions were bound to anionic sites of the chorion. Lowering the incubation pH could affect heavy metal binding to the chorion by neutralization of these anionic sites. It is important, in view of the acidification problem, to know the pH range at which chlorionic binding of metals is reduced and whether metal uptake by the embryo is affected. In this study the authors have examined the uptake of Cd by chorion, embryo and yolk of Atlantic salmon eggs and of alevins resulting from three levels of Cd exposure, at each of four incubation pH's.