micronucleus, nucleoplasmic bridge, and nuclear budding in peripheral blood cells of workers exposed to low level benzene

background: benzene is one of the important occupational pollutants. there are some reports about the leukemogenic effects related to low-level exposure to benzene. objective: to study the frequency of micronucleus (mn), nucleoplasmic bridge (nb), and nuclear budding (nbud) in the peripheral blood lymphocytes of petrochemical workers with low level exposure to benzene. methods: we enrolled 50 workers exposed to low-level benzene and 31 unexposed workers of a petrochemical industry. after exclusion of 3 samples, peripheral blood lymphocytes of the remaining 47 exposed and 31 unexposed workers were analyzed for the frequency of mn, nb, and nbud by cytochalasin-blocked mn technique. results: mn was present in 28 (60%) exposed and 18 (58%) unexposed workers. nb was observed in 6 (13%), and 2 (7%) exposed and unexposed workers, respectively; the frequency for nbud was 20 (43%), and 13 (42%), respectively. no significant difference was found in the observed frequencies of mn, nb, and nbud in the peripheral blood lymphocytes between the exposed and unexposed group workers. conclusion: occupational exposure to low-level benzene does not increase the frequency of mn, nb, and nbud in the peripheral blood lymphocytes, biomarkers for dna damage.