Evaluation of the genotoxic, mutagenic, and histopathological hepatic effects of polyoxyethylene amine (POEA) and glyphosate on Dendropsophus minutus tadpoles

Herbicides improve the productivity of a monoculture by eliminating weeds, although they may also be toxic and have negative effects on non-target organisms, such as amphibians. The present study evaluated the genotoxic, mutagenic, and histopathological hepatic responses of Dendropsophus minutus tadpoles to acute exposure (96 h) to the herbicide glyphosate (GLY, 65, 130, 260 and 520 mu g/L) and the surfactant polyoxyethylene amine (POEA, 1.25, 2.5, 5 and 10 mu g/L). On average, 174 % more genomic damage was observed in the tadpoles exposed to all concentrations of POEA in comparison with the control, while up to seven times more micronuclei were recorded, on average, at a concentration of 5 mu g/L of POEA. All the individuals exposed to 10 mu g/L of POEA died. The tadpoles exposed to GLY presented 165 % more DNA damage than the control, on average, at the highest concentrations (260 and 520 mu g/L), and up to six times more micronuclei at 520 mu g/L. The Erythrocyte Nuclear Abnormality test (ENA) detected a relatively high frequency of cells with lobed nuclei in the tadpoles expose to POEA at 5 mu g/L and binucleated cells in those exposed to GLY at 520 mu g/L. The hepatic histopathological observations revealed several types of lesions in the tadpoles exposed to both GLY and POEA. Overall, then, the results of the study indicate that both GLY and POEA have potential genotoxic, mutagenic, and hepatotoxic effects in D. minutus tadpoles. We emphasize the need for further studies to monitor the amphibian populations, such as those of D. minutus, which breed in aquatic environments associated with agricultural areas. The release of pollutants into natural habitats may have significant long-term impacts on the survival of anuran tadpoles.

Automated summary

The study evaluated the genotoxic, mutagenic, and histopathological hepatic responses of Dendropsophus minutus tadpoles to acute exposure to the herbicide glyphosate and the surfactant polyoxyethylene amine. Results showed that both glyphosate and polyoxyethylene amine have potential genotoxic, mutagenic, and hepatotoxic effects in the tadpoles, with polyoxyethylene amine showing a higher impact. Findings emphasize the need for continued monitoring of amphibian populations in agricultural areas to mitigate the long-term impacts of pollutants on anuran tadpoles.