Multiple Toxicity and Accumulation of Heavy Metals in Two Bivalve Mollusc Species

Abstract

Single and combined additions of copper (0.2 mg/l), zinc (0.4 mg/l) and manganese (2 mg/l) were used to examine the multiple accumulation and toxicity of these metals in sessile blue mussel Mytilus edulis L. and burrowing clam Macoma baltica (L.) in a 23-factorial experiment. Concentrations of metals were analysed with atom absorption spectrometry. The accumulation of metals and their toxicity were determined by regression analyses. The presence of copper ions stimulated the accumulation of zinc and manganese in mussels so that the concentration of manganese was 100 % and zinc 25 % higher than without copper additions. In accumulation of manganese and copper in clams, other metals did not have any effect and zinc did not accumulate at all. The values of lethality (LC50) were 127/µg Cu/l for mussels in 8 days and 54 µg Cu/l for clams in 10 days.