Cytogenetic changes in subjects occupationally exposed to benzene.

Humans are exposed to benzene from various occupational and environmental sources. The genotoxic effects of benzene were assessed in peripheral blood lymphocytes of 36 workers employed in the shoe industry for a period extending from seven months to over 30 years. Chromosomal aberrations and sister chromatide exchanges were used as indicators of genotoxic effects. The incidence of dicentric chromosomes in the exposed group was significantly higher than in the control group (P < 0.05). No significant increase was detected between the working period in the exposed group and chromosomal aberrations. Sister chromatide exchange (SCE) frequency was not significantly increased in the exposed group.