Metal concentrations in bivalves living in and around copper mine tailings released after a tailings dam breach

Samples of the common blue mussel Mytilus edulis, the soft-shell clam Mya arenaria, and sediment were collected from Little Bay Arm in Notre Dame Bay, NF, Canada, in September 1999 following the breach of a wooden-crib and rubble tailings dam, and concentrations of metals were measured. Concentrations of copper, vanadium, manganese, cobalt, and iron were significantly higher in both bivalve species at the study site compared to samples from a control site, but mussels had higher concentrations than clams of all metals except copper and nickel. Analysis of the sediment indicated that the animals were accumulating excess metals from the tailings. For human consumption, the greatest concern was noted for lead, but the overall risk was determined to be quite low.