Multianalyte voltammetric determination of traffic-linked metals in marine organisms employed as pollution bio-monitors

A new procedure is proposed for the voltammetric determination of ultra-trace cadmium(II), copper(II), lead(II), platinum(II), palladium(II), rhodium(III) and zinc(II) by a single run of square wave adsorptive catalytic stripping voltammetry. The voltammetric cell was based on a typical three-electrodes set-up: working electrode (stationary hanging mercury drop), reference electrode (Ag|AgCl|KClsat) and auxiliary electrode (platinum). The supporting electrolyte contained the formazone complex together with dimethylglyoxime and the disodium salt of ethylenediaminetetraacetic acid. Validation of the analytical procedure was obtained by the analysis of standard reference materials (Mussel Tissue BCR-CRM 278, Oyster Tissue NIST-SRM 1566a). Comparison with spectroscopic measurements was performed. Good accuracy was achieved. The analytical procedure was finally applied to mussels and clams sampled on the mouth of Po river, employed as bio-monitors.