PM05 Aquatic Vertebrate/Invertebrate Toxicology
Exhibit Hall
8:00 AM - Monday, 10 November 2003
(PM103) OXIDATIVE STRESS IN A FISH SPECIES EXPOSED IN SITU TO EFFLUENTS OF A BRAZILIAN PULP AND PAPER INDUSTRY.
Rosa, Alexandre1, Lima, Patricia1, Sell, Fabiola1, Ferreira, Fabiula 1, Soares, Carlos1, Wilhelm Filho, Danilo1, 1 Universidade Federal de Santa Catarina, Brazil, Florianopolis, SC, Brazil
ABSTRACT- Effluents related to the bleaching process of pulps are quite problematic considering their high content of chlorophenol, resin acid, organic acids and other substances of high toxicity. Adult male fish from a local species (Pimelodus sp; n=10) were caught in Rio Canoas, a polluted river from South Brazil, in three different sites in relation to a pulp mill industry existent in that river: site A, localized 5 km upstream (reference site), site B 4 km downstream, and site C localized 35 km downstream. After fish were killed, the liver were examined for enzymatic and non-enzymatic antioxidants. No significant differences were found in hepatic TBARS and GSH concentrations, and in the activites of glutathione S-transferase and superoxide dismutase. Nevertheless, the activities of glutathione peroxidase, catalase and glutathione reductase were higher in fish caught dwonstream to the effluent emission (site B), in relation to site A (reference site), but were not different from the actitivies found in site C. It is concluded that Pimelodus sp sampled near the emission of pulp mill effluents are facing a moderate oxidative stress, in agreement with data obtained in fish exposed sub-chronically in laboratory (tilapia exposed to four weeks). Apparently, fish sampled in site C are not under heavy influence of xenobiotics from that industry.
Key words: tilapia, pulp and paper, oxidative stress, enzyme