Cadmium in edible crabs (Cancer pagurus L.) from Scottish coastal waters

Concentrations of cadmium in the hepatopancreas (0.1-61.3 mg kg-1), gonad (0.15-11.0 mg kg-1) and gills (0.2-10.7 mg kg-1) of the edible crab Cancer pagurus L. from 16 sampling sites round the Scottish coast are reported, and compared with published elevated concentrations in crabs from the Orkney Islands. Geographical variations in the distribution of cadmium between organs indicate that the dietary uptake of cadmium is predominant in northern mainland and Orkney crabs, but that uptake from the water is more important in the south of Scotland. Mean dissolved cadmium concentrations in eastern coastal water increase from approximately 10 ng dm-3 in northern waters to approximately 25 ng dm-3 in the south. It seems likely that a regional contamination of the environment by cadium of geological origin occurs in the extreme north coast of Scotland, and in the Orkney and Shetland areas.