CHROMOSOME ABERRATION, SISTER-CHROMATID EXCHANGE, PROLIFERATIVE RATE INDEX, AND SERUM THIOCYANATE CONCENTRATION IN SMOKERS EXPOSED TO LOW-DOSE BENZENE

Cytogenetical endpoints, i.e., chromosome aberration (CA), sister-chro matid exchange (SCE), and proliferative rate indexes (PRI), were measu red in peripheral blood lymphocytes (PBL) of 42 workers exposed occupa tionally to low-dose benzene, and of 42 controls. The role of smoking habit as a confounding factor of genotoxic effects caused by occupatio nal low-dose benzene exposure was also studied. The benzene concentrat ions in the ambient air samples varied from 3 to 20 mg/m3 (mean: 7 mg/ m3). The continuous low-dose benzene exposure significantly increased the CA and SCE frequencies, but did not influence PRI. Smoking levels were characterized by subjective accounts and by serum thiocyanate con centrations (SCN). CA and SCE were not significantly increased in smok ers compared to nonsmokers, but the differences were expressed to a gr eater extent in the case of measurement of SCN concentrations. Determi nation of SCN proved to be more objective in the assessment of genotox ic effects of smoking as a confounding factor of occupational low-dose benzene exposure. (C) 1994 Wiley-Liss, Inc.