Workers exposed to styrene in the reinforced plastics industry show a significant increase of chromosome aberrations, mainly chromosome breaks, in peripheral blood lymphocytes. The high incidence of aberrant lymphocytes (mean 15.1 +/- 4.8%; referents 2.0 +/- 1.3 %) was retained when the same men were reexamined one year later (mean 16.2 +/- 2.9 %). However, the frequency of sister chromatid exchanges (SCE), a newly developed sensitive parameter for the detection of recombinational exchanges linked with DNA repair, was not significantly increased (mean 5.3 +/- 1.0 SCE/cell) in comparison to the referents (mean 4.4 +/- 0.6 SCE/cell). This finding suggests a specific role of styrene or its metabolites in inducing genetic lesions mainly manifesting themselves as chromosomal breaks.

Key terms chromosome aberration; exposure; lymphocyte; sister chromatid exchange; styrene; styrene exposure; worker