[Occupational Health Risk Assessment of Low Concentrations Benzene Toluene and Xylenes]

Objective: To Assess occupational health risks of exposuring to low concentrations (lower than occupational exposure limit, OEL) benzene, toluene and Xylenes. Methods: Qualitative evaluation, semi-quantitative evaluation and quantitative evaluation from guidelines for occupational health risk assessment of chemicals in the workplace were conducted to assess occupational health risks exposure to benzene compounds in different workplaces of 5 manufacturing enterprises, respectively. Results: Concentrations of benzene, toluene and Xylenes in all workplaces were lower than OEL. Qualitative evaluation showed that occupational health risk level was 4 exposure to benzene and Xylenes in all workpalces, while 2 exposure to toluene. Semi-quantitative evaluation showed low level (2 of 5) risks in all workplaces exposured to benzene compounds excepted 4 workpalces exposured to benzene, the latter was moderate (3 of 5) . Quantitative evaluation gave unacceptable carcinogenic risk (higher than 10(-4)) of benzene in the wood toy manufactory, and the highest risk was (1.48~5.26) ×10(-4). The occupational health risks of benzene and Xylenes were all unacceptable (HQ>1) in 9 workplaces. Conclusion: There still need more attention to occupational health risks exposure to benzene, toluene and Xylenes lower than OEL.