Chromosomal aberrations in lymphocytes of workers exposed to low levels of styrene.

Chromosomal aberrations were studied in lymphocytes of 15 workers exposed to styrene and 13 controls. The average styrene concentration in the work room air was 24 ppm, and the levels of urinary mandelic acid were below 2 mmol/l. No significant increase in the rates of gaps and breaks was found. However, the rate of micronuclei was significantly increased, which indicates that the mitotic spindle mechanism may be more sensitive to styrene and its metabolites than DNA.