Mutagenicity of sediment and biomarkers of oxidative stress in fish from aquatic environments under the influence of tanneries.

The mutagenicity of interstitial water and organic extracts from the sediments in the Cadeia and Feitoria Rivers, RS, Brazil, were evaluated by Salmonella microsuspension bioassay using TA97a, TA98, TA100 and TA102 strains, in the absence and presence of S9 mix. At the contaminated site, the mutagenic responses for interstitial water, suggested the presence of frameshift and base pair substitution mutagens, including oxidative substances. Organic extracts presented direct or indicative mutagenesis to the TA97a, TA98 and TA100 strains.

Oxidative stress damage in the liver of fish and rats receiving an intraperitoneal injection of hexavalent chromium as evaluated by chemiluminescence.

The livers fractions of Oreochromis niloticus (Tilapia) and Wistar rats taken from treated animals to single intraperitoneal doses of hexavalent chromium (K(2)Cr(2)O(7)), were analyzed for tert butyl hydroperoxide-initiated chemiluminescence (CL), lipid peroxidation using thiobarbituric acid reactive substances (TBARS), enzymes superoxide dismutase (SOD) and catalase activities, and the quantification of cytochromes P450 and b5. The CL time course curve was significantly higher in O. niloticus treated with Cr(VI) at all times studied.