Chromosome changes and benzene exposure. A review.

Benzene exposure can induce chromosome aberrations in somatic cells (lymphocytes and bone marrow cells) of man and of experimental animals in vivo, as well as in some in vitro systems. Numerical and structural chromosome changes in bone marrow cells have been described in subjects with benzene haemopathy. Increased rates of structural chromosomal aberrations both of the "unstable" and of the "stable" type in cultured peripheral blood lymphocytes have been observed not only in subjects with chronic benzene poisoning, but also in individuals with past benzene haemopathy and in subjects with past benzene exposure without signs of poisoning; these findings persisted for years or decades after cessation of exposure. In some cases of benzene-induced leukaemias the cytogenetic pattern was variable, as it is true also for the "spontaneous" acute leukaemias. The possible implications of the finding of chromosome damage from benzene to bone marrow cells for the occurence of leukaemias are discussed. The possibilities and limitations of cytogenetic studies in the biological monitoring of subjects exposed to benzene are commented on.