Cytogenetic and molecular biomonitoring of agricultural workers exposed to pesticides in Brazil

The use of agricultural chemicals without correct protection may lead to alterations in the genetic material of cells and the possible development of several types of tumors. The individual genetic variability in the enzymes which metabolize agricultural chemicals is also involved in this process, such as when the enzymes are not efficient in the detoxifying process of the organism, the metabolic subproducts accumulate, contributing to the tumorigenic process. Cytogenetic monitoring was carried out on a group of 20 male workers occupationally exposed to a mixture of pesticides in the town of Sao Jeronimo da Serra, PR (Brazil). Student's t = test and Wilcoxon's test showed, respectively, that there was no significant difference between the chromosome aberration frequencies between the exposed and control groups and between the paired individuals. However, there was a significant difference in the two analyses regarding the mitotic index of the sampled individuals. Smoking and time of exposure to agricultural chemicals did not influence the cytogenetic responses obtained, but the mitotic index of the control individuals was higher than that of the exposed individuals from the different age groups. The GSTM1 gene polymorphism was 33% null. When statistical tests were carried out to assess the relationship of the GSTM1 genotypes with the chromosome aberrations and mitotic indexes, there was no significant difference. The CA frequencies found in this study were low, making it difficult to associate it with the GSTM1 gene polymorphism. (C) 2000 Wiley-Liss,Inc.