BTEX concentration and health risk assessment in automobile workshops

Abstract

This study focused on the measurement of BTEX (benzene, toluene, ethylbenzene, and xylene) concentrations in the air of indoor and outdoor environments of automobile workshops in Damghan, Iran. Air samples from twenty-five workshops were actively collected and analyzed using Gas Chromatography-Flame Ionization Detection (GC-FID). The results showed that the concentrations of BTEX were higher in the indoor air compared to the outdoor air. The highest mean concentration of benzene (153.22 ± 34.21 μg m⁻³), toluene (94.41 ± 25.25 μg m⁻³), and xylenes (385.38 ± 34.21 μg m⁻³) was found in auto paint (AP) workshops, while the highest mean concentration of ethylbenzene (43.39 ± 12.57 μg m⁻³) was observed in auto body (AB) workshops. The significant negative correlations between benzene, ethylbenzene, xylene isomers, and relative humidity (RH) indicated that controlling humidity is an effective strategy. The mean inhalation lifetime cancer risk (LTCR) for benzene in both indoor and outdoor air of all automobile workshops exceeded the EPA (Environmental Protection Agency) recommended limits. The highest mean LTCR values for benzene and ethylbenzene were observed in the AP (3.24E10-4) and AB (2.95E10-5) workshops, respectively. The hazard quotient (HQ) of benzene and Xylene in the indoor air of the AP and AB workshops was >1, which indicates that the non-carcinogenic risks associated with exposure to these compounds are considerable. This study underscores the need for international attention to BTEX pollution in automobile workshops, highlighting the global health risks. The findings provide crucial data for developing strategies to mitigate these risks and protect workers’ health.