Chromosome aberrations and sister chromatid exchanges in styrene-exposed workers with reference to their smoking habits.

The incidences of chromosome aberrations and the frequencies of sister chromatid exchanges (SCE) were investigated in cultured lymphocytes of 18 styrene-exposed workers in comparison with six controls. There was a marginal increase in the incidence of structural chromosomal aberrations in first-division metaphases in the styrene-exposed workers, as compared with the nonexposed controls. However, there was no difference in SCE frequencies. When each group was divided into smokers and nonsmokers, styrene-exposed smokers tended to have higher SCE frequencies than styrene-exposed nonsmokers. Furthermore, cell proliferation was inhibited in styrene-exposed workers (both smokers and nonsmokers) and control smokers.