CONCENTRATIONS AND GEOCHEMICAL ASSOCIATIONS OF Pb AND Zn IN SEDIMENTS OF THE RIVER SAO FRANCISCO IMPACTED BY WASTES FROM INDUSTRIAL ZINC PRODUCTION

摘要

CONCENTRATIONS AND GEOCHEMICAL ASSOCIATIONS OF Pb AND Zn IN SEDIMENTS OF THE RIVER SAO FRANCISCO IMPACTED BY WASTES FROM INDUSTRIAL ZINC PRODUCTION. Surface sediments from the River Sao Francisco were analyzed to investigate the impact, due to the presence of metals (Cd, Cu, Pb, Zn) in wastes from a metallurgical industry in the city of Tres Marias/MG, Brazil. The concentrations and geochemical associations of Pb, Zn and trace metals associated with the minerals employed in zinc production were measured. Sediments close to discharge locations were highly contaminated with Pb (332-512 mu g g(-1)) and Zn (7872-10780 mu g g(-1)), with values decreasing rapidly due to dilution and hydraulic sorting. Evaluation of toxicity according to the Consensus-based Sediment Quality Guidelines indicated for Cd, Pb and Zn a high probability of adverse effects on aquatic biota at these sites.