DISTRIBUTION OF HEAVY-METALS IN THE ECHINOID PARACENTROTUS-LIVIDUS FROM THE MEDITERRANEAN POSIDONIA-OCEANICA ECOSYSTEM - SEASONAL AND GEOGRAPHICAL VARIATIONS

The concentrations of Zn, Pb, Cd, Fe, Cr, Cu, and Ti were measured in specimens of the echinoid Paracentrotus lividus from three Posidonia o ceanica meadows in the NW Mediterranean (Marseille, France; Ischia, It aly; Calvi, Corsica). Investigated metals were selectively distributed among the echinoid body compartments (i.e. body wall, Aristotle's lan tern, digestive wall, and gonads); their concentrations were influence d by season. The present work emphasises the need to consider both bod y compartment and sampling period as important factors in studies inte nding to use P. lividus as a biomonitor species. In particular, digest ive wall and, secondarily, body wall and gonads are recommended for us e in biomonitoring programmes, though with some restrictions for gonad s. Concentrations of most metals differed significantly in the echinoi d body compartments according to the seagrass meadow considered. Howev er, these differences were generally of low amplitude, except for Fe a nd Ti (contaminations by these two metals showed significant departure s from background concentrations in echinoids from Ischia). Results su ggest that the meadows of Calvi and Marseille, although subject to dif ferent pollution status (the meadow of Calvi is considered as a refere nce meadow while the Marseille meadow is exposed to intense domestic a nd industrial discharges), showed similar patterns of metal contaminat ion. (C) 1998 Elsevier Science B.V. All rights reserved.