Use of biomarkers for monitoring of waters from the Arara Stream in the city of Rio Brilhante, MS, Brazil

Abstract

This study evaluated the mutagenicity, genotoxicity and cytotoxicity of water samples from the Arara Stream in the city of Rio Brilhante, MS, Brazil, by means of toxicological tests using biomarkers. The micronuclei test was used to evaluate mutagenicity, and the comet assay was used to evaluate genotoxicity; both tests used Astyanax altiparanae. The Allium cepa test was used to analyze cytotoxicity. The collections were performed in April and June, 2013, at three different points (points 1, 2 and 3) of the Arara Stream and at the Irrigation Tank of UFGD (point 4). The results indicated greater frequency of piscine micronucleus in the June collection than in that of April. In the Allium cepa test, the cytotoxic effect was significantly greater in the collection of April, but the genotoxicity of water showed no statistical difference between the months of collection. The greatest amount of damage in the comet assay occurred at point 4, in both collection periods. The chemical analyses revealed that the levels of cadmium, chromium, copper and nickel were higher than the values allowed by legislation. The presence of pollutants above the permitted level in the analyzed samples of the Arara Stream shows possible potential mutagenic, genotoxic and cytotoxic effects to the water bodies due to these pollutants which may or may not be caused by human action. This work may thus contribute an additional tool to the quality control of water of the Arara Stream, considering its use and importance to the city.