Efeitos mutagênicos da poluição atmosférica em Tradescantia pallida no distrito de Moreira César, em Pindamonhangaba, SP Mutagenic effects of the atmospheric pollution on Tradescantia pallida in the district of Moreira César, in Pindamonhangaba, SP

The human species, along its history of occupation of the Earth, has been changing the environment to ensure better sur vival conditions. The consequences of its actions result in the environmental unbalance, and has serious implications for the ecosystems and to men’s own health. This study had the purpose to assess the mutagenic effects of urban environmental pollution by using the micronucleus test in Tradescantia pallida. Homes approximately 100, 1000 and 7000 meters apart, around a paper industry in the district of Moreira Cesar (Pindamonhangaba-SP) were chosen. For 11 months, at every 15 days young inflorescences were collected and fixed in ethanol/acetic acid (3:1), stored in alcohol 70% under refrigeration until the slides were prepared. The inflorescences were submitted to maceration along with the carmin acetic dye and the number of micronucleus in 300 tetrads for each slide was quantified. 10 slides were prepared per month, from each study location. According to the Kruskal-Wallis variance analysis, there was a significant difference between the three study locations, when compared among themselves (H = 21.94; p = 0.00). The average number of micronucleus in the three locations ranged from 0.00 to 1.87. The lowest value was observed in the control point (7000 m), with average and standard deviation of 0.03 ± 0.03. The highest average value was 1.87 ± 0.51, found in the location closest a paper industry (100 m), and 1.73 ± 0.48 micronucleus in the location 1000 m away from the plant. This result raises a concern with the quality of the air around polluting areas, and the need of try to determine limits of a safety margin for the propagation of these pollutants, in order to preserve the health of the population that lives around these regions.