Respostas histopatológicas e genotóxicas em peixes de água doce expostos a ambientes antropizados

Abstract

Anthropic activity can be defined as all human action that impacts the environment. Anthropogenic activities have been potentiated in the last decades by economic and social demand, increasing the production of waste through industrial activities, agriculture, livestock and disorderly urbanization of the cities, resulting in the contamination of natural resources, mainly of water bodies considered as ecosystems more fragile. The present study aimed to evaluate the occurrence of environmental contaminants in anthropic areas of the Ijuí River by means of histopathological responses in gills and fish livers captured in five points of the river, as well as to perform genotoxic analysis using the Micronucleus Test (MN) and Nuclear Abnormalities (AN) in peripheral erythrocytes of these organisms. The results obtained through histopathological analysis showed a predominance of moderate changes in gills and severe changes in the liver in all analyzed points, revealing the occurrence of xenobiotics in the waters of the Ijuí River, capable of inducing compromising lesions in organs vital to fish. For the MN test, the results indicated that in only one of the five collection points evaluated, the MN frequencies in fish presented higher than expected, since the AN frequencies were higher than the MNs at all points. In this way the tests used in this research proved to be efficient parameters to evaluate the presence of pollutants in a water body, in addition, it was verified that the contaminants induce genetic and physiological metabolic damages in fish, giving clear evidence that the anthropization in the Ijuí river is affecting eukaryotic organisms.