Fish biomarkers as tools for assessing water quality

CAZENAVE J.

BIOCELL

INST HISTOL EMBRIOL-CONICET

Lugar: Mendoza; Año: 2011 vol. 35 p. 202 - 202

0327-9545

In recent years, the levels of xenobiotics in aquatic environments have increased due to anthropogenic activities, which could lead to a decrease in natural resources. For this reason, there has been a growing awareness to develop methods for the early detection and assessment of adverse effects of pollutants on the biota. Particularly, fish are affected by all impacts on the water body, reflecting early environmental stress situations. Our work is aimed at evaluating the use of biological responses (biomarkers) in fish to evaluate water quality changes. Thus, we carried out both laboratory and field studies, using a set of biomarkers (morphological indexes, haematological and biochemical parameters, detoxification and oxidative stress markers, histopathological analyses). In fact, we assessed biomarkers responses in 3 fish species (Prochilodus lineatus, Cichlasoma dimerus y Piaractus mesopotamicus) exposed to the organochlorate insecticide endosulfan, under experimental conditions. Results showed that low pesticide concentrations are able to bring about immunological disorders as well as oxidative stress induction. On the other hand, we assessed water quality of the Salado river basin by using biomarkers in Prochilodus lineatus. The measured biological responses revealed differences in fish health status at different sampling sites, which may reflect unfavorable environmental conditions for fish life. Summarizing, our experience demonstrates that biochemical, physiological and histological markers are sensitive tools for assessing the sublethal effects of pollutants and environmental quality; so we suggest the use of biomarkers in future freshwater aquatic systems monitoring. In order to continue identifying the most effective tools, we are currently studying the effects of toxic mixtures on fish health and biomarkers responses of fish exposed in situ to point sources of pollution.