Exploring the clastogenic effects of air pollutants in Sao Paulo (Brazil) using the Tradescantia micronuclei assay

This study was designed to determine the clastogenicity of particulate matt er (aerodynamic diameter smaller than 10 mu m) in the urban polluted air in the city of Sao Paulo, The Tradescantia-micronucleus (Trad-MCN) assay was used throughout this study to evaluate the clastogenicity of the extracts o f the particulate matter. Tradescantia pallida (Rose) Hunt. cv, purpurea, a n indigenous cultivar, was used in the Trad-MCN assay. The efficacy of this plant material for the Trad-MCN assay was validated with dose-response stu dies using formaldehyde and beta radiation, Dose-response curves were estab lished with these known mutagens. The extracts of the PM,, particles at con centrations between 5 and 50 ppm induced a dose-related increase in MCN fre quencies. The results indicate that T. pallida is equally sensitive to muta gens as the standard Tradescantia clone 4430 or 03 and the particulate matt er in the urban air are clastogenic to the chromosomes of this plant. Inhal ation of these particles by urban dwellers may affect their health by induc ing similar genetic damage. (C) 1999 Elsevier Science B.V. All rights reser ved.