THE STUDY OF DNA OXIDATIVE DAMAGE IN BENZENE-EXPOSED WORKERS

Peripheral blood lymphocyte 8-hydroxy-2-deoxyguanosine (8-OHdG), were detected in 87 benzene-exposed and 30 control subjects by high perform ance liquid chromatograph coupled with an electrochemical detector sys tem (HPLC-EC). The air concentration of benzene and its homologes in t he workplace, urinary trans,trans-muconic acid (TTMA) as an internal d ose of benzene exposure, were examined. The lymphocyte micronuclei (MN ) as genotoxic and white blood cell (WBC) count as well as the myeloto xic markers of benzene were examined. Exposure to low, medium and high concentrations of benzene resulted in increased levels of 8-OHdG, whi ch were 4.67, 26.12 and 29.89/10(5) dG, respectively, However, the 8-O HdG level observed in the control group was 3.738/10(5) dG). A good co rrelation between 8-OHdG formation and the groups exposed to external and internal benzene was observed (r = 0.77, 0.64, respectively). Ther e was also a correlation between 8-OHdG and MN formation (r = 0.50). W BC levels were within normal range in all benzene-exposed subjects. It may be concluded that: benzene induced DNA oxidative damage in occupa tional exposure workers. The major factors influencing blood the 8-OHd G level were sex and toluene.