Accumulation of radionuclides by common mussel Mytilus edulis and purplish bifurcate mussel Septifer virgatus

The accumulation of 60Co, 59Fe, 54Mn and 65Zn by common mussel Mytilus edulis and purplish bifurcate mussel Septifer virgatus from seawater was investigated. High accumulation of 59Fe in Mytilus and 54Mn in Septifer was observed in the uptake experiments. Differences in biological half-lives between the two species was observed for 54Mn and 59Fe. The organ-specific concen-tration of radionuclides observed in the mussels was high accumulation of 60Co in kidney andviscera, 59Fe in kidney and viscera, 65Zn in kidney but was not observed for 54Mn although the accumulation of 54Mn in mantle was different between the species. Autoradiography was applied to examine the details of the distribution of 59Fe in the soft parts of the mussels.