Benzene is an established cause of human
leukemia that is thought to act by producing
chromosomal aberrations and altered in cell differentiation. In several recent studies increased levels of
chromosomal aberrations in peripheral blood lymphocytes were correlated with a heightened risk of
cancer, especially
hematological malignancies. Thus,
chromosomal aberrations may be a predictor of future
leukemia risk. Previous studies exploring whether
benzene exposure induces
chromosomal aberrations have yielded mostly positive results. However, it remains unclear whether the
chromosomal aberrations induced by
benzene occur in a distinct pattern. Here, we thoroughly review the major chromosome studies published to date in
benzene-exposed workers,
benzene-poisoned and
preleukemia patients, and
leukemia cases associated with
benzene expose. Although three cytogenetic markers (
chromosomal aberrations, sister chromatid exchanges, and micronuclei) are commonly examined, our primary focus is on studies of
chromosomal aberrations, because only this marker has so far been correlated with increased
cancer risk. This review surveys the published literature, analyzes the study results, and discusses the characteristics of effects reported. In most studies of currently exposed workers, increases in
chromosomal aberrations were observed. However, due to the relatively small number of affected individuals and variability in the reported aberrations, firm conclusions cannot be made about the involvement of specific chromosomes or chromosome regions. Further, in
leukemia cases associated with
benzene exposure, there is no evidence of a unique pattern of
benzene-induced
chromosomal aberrations in humans.
Leukemia cases associated with
benzene exposure are, however, more likely to contain clonal
chromosome aberrations then those arising de novo in the general population.