Cytogenotoxicity of urban fluvial waters in Presidente Prudente (SP), Brazil, using the Allium cepa test

Abstract

Several health problems can arise from the interaction of people with polluted environment. Many of the contaminants thrown in the environment can have toxic and mutagenic properties. Detection of these agents can be performed through bioassays with higher plants, such as common onion (Allium cepa L.), which is widely used, because of its low cost and high sensitivity. This work evaluated the water quality of the Limoeiro stream in Presidente Prudente (SP), Brazil, by analyzing the cytotoxic and mutagenic potential, using the Allium cepa test system in five different points of the stream and in two periods of the year (rainy and dry seasons). By calculating and comparing mitotic index and chromosomal abnormalities with a negative control, we observed that all the evaluated points presented some level of contamination. These data were analyzed together with the results of the physical-chemical and biological analyzes, which were also carried out in the same places. The springs were the only place that did not present cytotoxicity or genotoxicity, but some chemical values ​​were relevant. The Balneário da Amizade (a recreational area located within the urban area) and the effluent place of Limoeiro Sewage Treatment Station (STS) were the points that were most impacted by pollution, since they presented significant values ​​in several analyzed parameters and in both periods of the year. The other sample collection points showed significant values, however, in a smaller number of parameters or less frequently. Other factors should be evaluated in order to have a better understanding of the agents that cause these changes, and obtaining more data on the polluting sources will enable the identification of other compounds that may have influenced the results obtained in this work.