Accumulation and tolerance to cadmium, copper, lead and zinc by the green mussel Perna viridis

The green mussel Perna viridis (Bivalvia: Mytilacea) was exposed to a range of dissolved concentrations of Cd, Cu, Pb and Zn for 21 d.Accumulation of Zn has been interpreted in terms of a regulation mechanism to maintain constant body concentrations at ca 100 ~g Zn g-' dry wt at external dissolved Zn levels up to a threshold concentration (between 178 and 362 pg Zn I-').Beyond this threshold, net accumulation of body Zn continued until body Zn concentration reached a plateau at 200 pg Cadmium, Cu and Pb were linearly accumulated by P. viridis in proportion to ambient metal concentrations over 7 d.Toxicity of Cd, Cu, Pb and Zn was evaluated in 96 h bioassays; LC-50 values in pg 1-' were 620 for Cu, 1570 for Cd, 6090 for Zn, and 8820 for Pb.