Assessment of occupational health risk due to inhalation of chemical compounds in an aircraft maintenance, repair, and overhaul company

Abstract

This study was conducted in an aircraft maintenance, repair, and overhaul (MRO) company in 2021 to identify the extent of occupational exposures and quantitative assessment of the health risk due to inhalation of chemical compounds. According to the inspection of different parts of this company, heavy metals including Co, Cd, Ni, Pb, Cr(VI), and Mn and organic compounds including benzene, toluene, ethylbenzene, xylene (BTEX), and methyl ethyl ketone (MEK) were selected for health risk assessment. In total, the air in the inhalation area of active workers was sampled in 51 workstations. Measurement of the above pollutants showed that the average occupational exposure to Cd, Pb, and all organic compounds fell within the acceptable range of occupational exposure standard, while the measured values for Co, Ni, Mn, and Cr(VI) exceeded the standard limit. According to calculations, the highest carcinogenic risk (CR) was seen in the plating (airplane) workshop for exposure to Cr(VI) (7.58E-01), and the lowest CR was observed in the electronic workshop for exposure to Pb (7.75E-08). The highest non-carcinogenic hazard (HQ) was found in the welding workshop for exposure to Co (1.00E + 04), while the lowest HQ was related to toluene in the fabrication workshop (9.10E-03). Considering the high rate of exposure indicators, CR and HQ exceeded the standards set by the American Environmental Protection Agency (EPA) in most workshops. Accordingly, company managers should take the necessary measures to reduce the vulnerability of individuals working in areas with unacceptable CR and HQ.