Identification of mutagen exposures in the rubber industry by the sister chromatid exchange method

The rubber industry is known to use a large and expanding array of chemicals, some of which are experimentally proven mutagens or carcinogens. An association with cancer risk has been shown in several epidemiological studies carried out in the rubber industry. Sister chromatid exchanges were studied in blood lymphocytes of 54 workers from various job categories in two rubber plants and 34 control subjects mainly from office jobs. The highest numbers of SCEs were observed among rubber workers who smoked, but smokers in the control group also differed significantly from non-smokers by their incidence of SCEs. In both rubber plants the highest incidence of SCEs was observed among workers employed in the mixing operations of the rubber chemicals.