Groves, Phillip a. creator Carrasco-Letelier, Leonidas Eguren, Gabriela Teixera de Mello, Franco text ag 2006 continuing eng 8 páginas The implementation of eco-toxicological assessment in South America is presently limited due to significant scientific information gaps concerning native species and their potential use as biomarkers. Recently, a common southern hemisphere fish species, Astyanax fasciatus, has been pointed out as a potential bio-indicator to anthropogenic pollution. This is a small, abundant, Neotropical characid, which is widely distributed from Central America south, to the Rio de la Plata Basin of western Uruguay. Our study found a statistically significant increase of coproporphyrin, uroporphyrin and protoporphyrin concentrations in hepatic tissues of A. fasciatus collected from a stream segment with high anthropogenic disturbance (due mainly to agricultural derivatives and motor vehicle transportation activities). Although the area studied showed differences in up and downstream limno-chemical parameters, these differences were not related to the increase of hepatic porphyrin concentrations. Based on the results of our study, we conclude that A. fasciatus is a good bio-indicator of exposure to environmental contaminants, and we propose that this abundant fish species be considered as a sentinel organism for monitoring potential disturbances to freshwater ecosystems. Disponible en caja 17 no 4 de INICNE Astyanax Fasciatus Toxicología Toxicity Contaminantes Ambientales Pollution Peces de Agua Dulce Inland Waters Freshwater Fish Argentina Uruguay 234694 v. 62 n. 8 (2006) AR-ReUNN 260630 20260702003057.0 234695 spa