Geochemical and ecotoxicological assessment for estuarine surface sediments from Southern Brazil

Sediments from Guaratuba Bay (PR, Brazil), a marine protected area, were collected and evaluated for geochemistry and toxicity. High levels of P and acute toxicity were observed in some samples. Concentrations of Cu, Cd, Pb and Zn were relatively low; however, Cd levels eventually exceeded Threshold Effect Level. Toxicities were associated to nutrients and metals enrichment. Results suggest that impacts are incipient and occur only at specific sites, associated to multiple contamination sources. Despite sediments quality seems to range between good and fair, attention is required to land-use planning around Guaratuba Bay and controlling local pollution sources.

► Guaratuba Bay sediments exhibited organic enrichment and toxicity.
► Toxicities associated to Cu and Zn and nutrients concentrations in GB sediments.
► Degradation is due to inputs from localized multiple contamination sources.
► In GB, contaminants accumulate close to the sources, affecting local biota.