Micronucleus frequencies in workers exposed to lead, zinc, and cadmium.

Micronuclei (MN) in blood lymphocytes were determined in 31 male workers occupationally exposed to lead (Pb), zinc (Zn), and cadmium (Cd) and 20 control workers matched for age and smoking habits. Exposed workers have higher MN mean values than control workers (p < 0.01). In exposed workers, blood Pb concentrations were also significantly higher than in control workers (p < 0.001), but the mean concentrations of Zn and Cd in the blood were not statistically significant compared to the controls (p > 0.05). These results suggest that lead may be genotoxic and the human lymphocyte micronucleus test can be used to assess genotoxic effects that result from occupational exposures.