Avaliação preliminar da genotoxicidade de filtro solar comercial em Astyanax sp

Abstract

The increase in production and consumption, in the last decades, of products containing compounds responsible for absorbing and/or reflecting UV radiation, has raised concerns about the impacts of these compounds in the environment, especially the aquatic environment. Therefore, it is of fundamental importance to study the effects of sunscreens in this environment, allowing measures to be taken to maintain the quality and biodiversity of water resources. Previous studies aimed at the quantification of sunscreens in water bodies, and their toxic effects on aquatic organisms, but their genotoxic effects are still poorly understood. For this reason, this study aimed to evaluate the genotoxic potential of a commercial sunscreen containing sunscreens benzophenone -3 and ethylhexyl methoxycinnamate, using fishes Astyanax sp as test organisms. The genotoxicity was assessed by comet assay, which detects DNA damage in organisms exposed to pollutants which, in long term, may cause mutagenicity, carcinogenicity or lead to lethality. There were two bioassays, an acute and subchronic, lasting 4 and 21 days, respectively. Then, the fish specimens were divided into five tanks and exposed to sunscreen by dissolving it in water. Each tank received a different concentration of sunscreen, as follows: 10, 100 and 1000μg/L of ethylhexyl methoxycinnamate and 23, 233 and 2333 μg/L of benzophenone-3 (Tank 1, 2 and 3). Two tanks were used for control, one of it containing filter water and another containing only the base of the sunscreen dissolved in water, without the UV-filters. After the exposure time, the fishes were anesthetized and sacrificed and the comet assay was held with their erythrocytes. Through statistical analysis by Kruskal-Wallis test, the acute bioassay showed significant differences between the control group and the Tanks 1, 2 e 3. In subchronic bioassay was observed mortality of 11 individuals during the twenty-one days of exposure, which occurred in the group exposed to the highest concentration, Tank 3. Statistical analysis of the subchronic bioassay showed significant difference between the control groups and Tanks 1, 2 e 3, as well as between the control and the different gel concentrations. These results suggest that sunscreen may cause DNA damage in Astyanax sp, both in acute exposure, as in the subchronic.