Chromosomal aberrations and sister chromatid exchanges in workers exposed to lead

The frequencies of chromosomal aberration (CA) and sister chromatid exchange (SCE) in the peripheral blood lymphocytes of 21 lead-exposed workers from a battery factory were studied, and their blood lead (Pb-B) levels were determined. The results demonstrated that when the mean Pb-B level reached 50 micrograms/dl, the CA percentage increased significantly compared with that of the nonexposed controls. The CA percentage increased as the mean Pb-B level increased, showing a dose-effect relationship. When the mean Pb-B level was as high as 80 micrograms/dl, the rate of SCE in the lymphocyte was also increased significantly, but no correlation was observed between these two parameters. On the basis of such results, lead should be considered an agent harmful to the human chromosome.