Uptake and release of lead and zinc by blue mussels. Experience from transplantation experiments in Greenland

Studies of release and uptake of lead and zinc in blue mussels have been used to assess the environmental impact of a lead-zinc mine in Greenland. Blue mussels were transplanted from a clean area to highly polluted sites near the mine, and also from a highly polluted site to a clean area. The uptake and release of lead were found to be slow processes. After two to three years of accumulation the level in the transplanted mussels reached the level of the resident population. After two to three years in a clean environment the release of lead ceased, and the mussels seem be able to depurate only about half of the lead originally taken up. The pattern of uptake and release of zinc was not as clear as for lead indicating a certain regulation capability of the mussels. When pollution with lead in the environment decreases, resident mussel populations were found not to be useful as monitoring organisms. Transplantation of mussels seems to be a good monitoring tool in that situation.