Biomarcadores genéticos para avaliação dos efeitos do herbicida 2,4-D (ácido 2,4-diclorofenoxiacético) sobre o peixe nativo Rhamdia quelen

Abstract

Before the commercial release of 2,4-D (2,4-dichlorophenoxy acid) resistant agricultural cultivars, the present study sought to analyze the biomarkers comet assay, micronucleus/erythrocytic nuclear abnormalities and vitellogenin, to evaluate if the concentration of this substance allowed by Brazilian legislation can trigger genotoxic, mutagenic effects or acting as an endocrine disruptor on the native fish species Rhamdia quelen. For this, a laboratory test was performed, where male specimens were submitted to acute water exposure (24, 48, 96 and 192 hours) at concentrations 0, 15, 30 and 60 μg of 2,4-D/L. Analyzes of these biomarkers did not reveal significant toxic effects, probably due to the low dosages employed. However definitive conclusions about the action of this compound on animal and human sanity still needs further investigation. It is therefore suggested to evaluate for longer periods of exposure using other contamination pathways (trophic example), considering the analysis of other biomarkers, embryo and in vitro cell cultures, and other species.