Chromosome aberrations and sister chromatid exchanges in lead-exposed workers

Chromosomal aberrations and sister chromatid exchanges (SCEs) were studied in peripheral blood lymphocytes of 18 workers exposed to lead in a smeltery and 12 unexposed controls. Chromosome aberrations were analysed from cells cultured for both 50 and 72 hours. No increase was detected in the frequency of aberrant cells in men occupationally exposed to lead as compared with the control group. However, among the lead-exposed men, the 72-h cultures yielded aberration rates significantly higher than at 50 h. Both among the exposed workers and the control men, smokers showed an increase (P<0.05) in SCEs as compared with non-smoking referents. Furthermore, smokers exposed to lead had higher (P<0.05) SCE frequencies (mean 11.7±0.4) than unexposed control smokers (mean 10.4±0.4).