BIVALVES AND HEAVY-METALS IN POLLUTED SEDIMENTS - A CHEMOMETRIC APPROACH

Copper, lead, cadmium, zinc, chromium, manganese, iron and nickel were determined in near-shore sediments in the harbour of Trieste (Norther n Adriatic), in an area highly exposed to urban and industrial wastes, where severe alteration of benthic population was observed. A typical bivalve of this area, Corbula gibba, was used as bioindicator of sea- bottom pollution. Multivariate statistical analysis of the chemical da ta interpret concentrations and distributions of heavy metals in these sediments, attesting anthropogenic source for Cu, Pb, Cd and Zn Using labile fractions of heavy metals in sediments as 'predictors', and le ngth or biomass of the bivalve as dependent variables, we obtained, by a multiple regression procedure, a predictive model showing the influ ence of metals on this benthic organism of this polluted area.