Bioaccumulation and toxicity of four dissolved metals in Paracentrotus lividus sea-urchin embryo

The bioaccumulation of four metals (Cd, Cu, ph, Zn) dissolved in water was assessed measuring the concentrations recorded within sea-urchin larvae (Pa racentrotus lividus, Lmk.) after a 48-h exposure period. Concurrently, the frequencies of abnormalities were evaluated at the 48-h pluteus stage to ch eck the actual toxicity of such contaminants with regards to larval develop ment. Maximum metal concentrations in the larvae reached 43.8+/-6.7 mug Cd g(-1) dry weight (d.w.), 1269 +/- 392 mug Cu g(-1) d.w., 3106 +/- 679 mug P b g(-1) d.w., 534 +/- 62 mug Zn g(-1) d.w. Bioconcentration factors (BCFs) reached very high values for Pb (maximum value: 16,282+/-973) and indicated that the concentrations of Pb and Cd were directly related to the water co ncentration at least in the range of concentrations tested. Zn appeared to be partially regulated above a certain threshold concentration (between 5 a nd 25 mug l(-1)). Cu was accumulated with an active uptake at least below l ethal threshold level (100 mug l(-1)). Nevertheless, above these thresholds , high mortality of embryos prevent any interpretation of Zn and Cu bioconc entration factors. Concurrent studies carried out on embryotoxicity confirm ed the high toxicity of Cu towards sea-urchin pluteus larvae and highlighte d the different behaviour of Cd. The internal Cd concentrations were direct ly related to the external ones, comparable to other non-essential metals, but Cd had little toxic effect on the initial larval development. (C) 2001 Elsevier Science Ltd. All rights reserved.