RESUMO
The present work has been accomplished in the basin of the Sangão River (Criciúma, South Brazil), which receives the rejects from coal washing, mainly heavy metals. In the tobacco cultures at the river banks several agrotoxics are used. We tried to detect and estimate the possible action of this environmental pollution on rodents directly exposed to it through the study of chromosome aberration frequency in the bone marrow. The same methodology was applied to rodents collected from a nonpolluted area of the same state (Florianópolis, 190 km from Criciúma). The results obtained showed significant differences in total chromosome aberrations at the different sites. There is therefore a suggestion that this methodology could be applied to detect the action of environmental pollution on organisms.