Patterns of heavy metals and Microtox toxicity in sediments from a polluted lagoon (Pialassa Baiona, Italy).

Microtox toxicity bioassays were performed on superficial sediments collected from selected stations throughout a polluted lagoon connected to the North Adriatic Sea, in Italy. At most stations, there was no distinct pattern between Cr, Cu, Ni, and Zn concentrations in sediments and the sediment toxicity, and consequently, the concordance in estimates of toxicity with ERM quotients was very small. Hg content in sediments exceeded ERL (0.15 ug/g) and ERM (0.71 ug/g) values at all channel and wetland stations, except at one wetland station, which reported the lowest toxicity with Microtox bioassay. These results are indicative at best and contemporaneous chemical/biological/ecotoxicological studies are needed to verify the applicability of SQG developed in the U.S. for use outside North America and determine the toxicity of sediments in Pialassa Baiona.