Tailpipe emissions from mining machinery and naturally occurring volatile organic compounds (VOCs) in the coal seam accumulate in a semi-closed environment, threatening the health of underground workers. In order to study the pollution characteristics and potentially harmful effects of volatile organic compounds (VOCs) in different working environments in coal mines, a coal mine in Huainan City, Anhui Province, China, was selected for VOC sampling. VOCs concentration levels, composition, and characteristics of the air in the air intake tunnel, the coal mining face, and the air return tunnel were obtained, and the health risks to workers were evaluated.
The findings of the research study indicate that: (1) The mean concentration of volatile organic compounds (VOCs) in the underground coal mine environment was found to be (2066.67±750) μg/m3, which is significantly higher than the background concentration of the ground environment collected on the same day (55.5±20.3) μg/m3. The mean TVOCs value in the air intake tunnel work environment was (1875±541.67) μg/m3, the mean TVOCs value in the coal mining face work environment was (2362.5±454.17) μg/m3, and the mean TVOCs value in the air return tunnel work environment was (1943±626.33) μg/m3. These findings suggest that VOCs affected the coal mining face most severely. (2) The top components in terms of their volume fraction of volatile organic compounds (VOCs) are isopropanol, carbon disulfide, cyclohexane, methyl bromide, cis-1,3-dichloropropene, chlorobenzene, benzyl chloride, trichloroethylene, n-decane, and chlorofluorocarbon-11. Halogenated hydrocarbons constituted the greatest proportion of VOCs in the three working scenarios, representing 41.9%, 40.9%, and 41.2%, respectively. Alkanes and OVOCs accounted for the next largest proportion, ranging from 24.2% to 26.1% and 17.2% to 21.9%, respectively. The concentrations of aromatic hydrocarbons and olefins accounted for 3.1% to 3.7% and 5.3% to 8.11%, respectively, of TVOCs. (3) The results of the health risk assessment indicated that the hazard index (HI) for the non-carcinogenic risk of volatile organic compounds (VOCs) in the underground coal mine environment ranged from 0.077 to 0.279, which did not exceed the threshold value of 1. Consequently, there was no non-carcinogenic health risk. The lifetime carcinogenic risk factor (RISK) ranges from 4.26×10-5 to 2.02×10−4, exceeding the threshold (1.00×10−6) by 42.6 to 202 times, indicating a relatively high carcinogenic risk.