DISSOLVED ZINC, CADMIUM AND LEAD IN TWO PORTIONS OF THE CANANÉIA-IGUAPE ESTUARINE-LAGOON COMPLEX AND ITS POTENTIAL EXPORTATION TO THE ADJACENT SYSTEMS

Abstract

The southern and northern sectors ofCananeia-Iguape estuarine-lagoon complex (São Paulo,Brazil) were studied in autumn-2007 (CNPq-INCTTMCOcean-VAGRA Projects) to evaluate theirhydrochemical characteristics considering theconcentrations of dissolved zinc, cadmium and lead. Themethodology used was anodic stripping voltammetry. In thesouthern sector the zinc concentrations ranged from 0.134 to0.341   μg L-1, the cadmium from 0.006 to 0.020 μg L-1 andthe lead from 0.036 to 0.100   μg L-1. In the northern sectorthe zinc concentrations ranged from 0.115 to 0.389   μg L-1,the cadmium from 0.012 to 0.024   μg L-1 and the lead rangedfrom 0089 to 0.236   μg L-1. These concentrations were belowthe limits proposed by the Brazilian environmental law(CONAMA) although revealing anthropic impact in thenorth region with exporting potential to the southern regionand to the continental shelf. Higher trace metalconcentrations were observed in the bottom waters near tothe sediment.Index Terms ⎯ Atrophic environmental impacts, dissolvedtrace metals, estuarine system.