occupational risk assessment of benzene in rubber tire manufacturing workers

tire manufacturing industry has a history of more than half a century in iran, where 14 thousand workers are employed. the old and semi-automated processes equipment, backward technology, and raw materials impurity lead to significant exposures to occupational carcinogens such as benzene. this study was to assessment of benzene exposures and evaluation the resulting cancer risk in two tire-manufacturing factories. one hundred workers in  two  target  tire-manufacturing factories  selected  as  ―exposed  group‖.  personal  monitoring was conducted in all process units according to niosh 1501 method. inhalation health risk of benzene exposure was estimated via two assessment models. data were analyzed using spss and quantitative values were reported as mean ± standard error. occupational exposure to benzene in 68 percent of workers has exceeded the current exposure limit. the highest level of benzene (5.06 ppm) found in cement making unit. the odds ratio of leukemia was 2.06 times the working population without benzene exposure, as well; the cancer incidence was 16.14 cases per 1000 workers. this study as screening approach is first on addressing the risk assessment of iranian tire manufacturing workers. the levels of personal exposures and cancer risk were unacceptable and this may provide a basis for developing the control measures in future.