CONICET | Buscador de Institutos y Recursos Humanos

Worldwide freshwater bodies that cross agricultural or urban areas are exposed to mixtures of xenobiotics.In particular, pesticides are usually part of these mixtures and could come into direct or indirectcontact with biota and therefore, organisms have to cope with this altered scenario and the detrimentaleffects of these substances. Commercial formulations of chlorpyrifos and glyphosate, and their mixtureswere evaluated using a set of biomarkers in the native fish C. decemmaculatus exposed to relevantenvironmentally pesticides concentrations. The biomarkers measured were: histopathological indicesand tissue ultrastructure in liver and nuclear abnormalities and micronuclei in erythrocytes. During 42days adult females were exposed to the following concentrations of Clorfox and Roundup Max (chlorpyrifosand glyphosate, respectively): 0.84 nl/l and 8.4 nl/l of Clorfox (CF), 0.2 and 2mg/l of Roundup Max(RM) and all the combinations of these concentrations. Being the low concentrations of both pesticidesenvironmentally relevant. Nuclear abnormalities of erythrocytes were registered under CF, RM and onlyone mixture. Histological inflammatory alterations increased in individuals exposed to CF and twomixtures. Finally, some pesticide combinations increased the circulatory alterations in liver. Ultrastructuralchanges in hepatocytes were registered at all the pesticide treatments. The different biomarkerresponses showed in the mixtures treatments reflected complex interactions, showing the mixture of thelow concentrations of both pesticides (the environmentally relevant), potentiated effects. According toour results the presence of these substances in freshwaters could impose important risks for naturalpopulations by causing deleterious effects on the native fish species C. decemmaculatus.