Background:

Air pollution have led to severe problem of adverse health effect in the world. This study aimed to conduct the health risk assessment, cancer risk analysis, and non-cancer risk for exposure to volatile organic compounds (VOCs) and hydrogen sulfide (H ₂ S) in petrochemical industry.

Methods:

In this cross-sectional research, 123 samples were collected in the ambient air in Iran during winter 2016. For sampling and analysis of VOCs and H ₂ S, 3 methods (numbers 1500, 1501, and 6013) presented by the National Institute of Occupational Safety and Health (NIOSH) were used. For determination of risk assessment of chemical pollutants, semi-quantitative method presented by the Occupational Safety and Health Division, Singapore was used. Finally, for calculation of cancer risk analysis, Chronic Daily Intake (CDI) and calculation of non-cancer risk, Exposure Concentration (EC) were used.

Results:

Average concentration of benzene (2.12±0.95) in breathing zone of workers were higher than the Threshold Limit Values-Time Weighted Average (TLV-TWA) (P<0.05). Among chemical substance, benzene had very high rank of risk in petrochemical industry. Rank of risk for H ₂S, toluene, and xylene present in the breathing zone of workers was low. The mean cancer risk for workers exposed to benzene was estimated 8.78×10^−3, in other words, 8.7 cancer per 1000 i.e. higher than the acceptable standard of 10⁻⁶. In our study, non-cancer risk for BTX was higher than the acceptable standard of 1.</p> <h3 id="sec-4title">Conclusion:</h3> <p>In particular, overall cancer and toxic risk can be associated with long term exposure to benzene.</p>