Respiratory functions and health risk assessment in inhalational exposure to vinyl acetate in the process of carpet manufacturing using Monte Carlo simulations

Vinyl acetate (VA) is a volatile compound and the main compound of the carpenter's glue. VA causes upper respiratory tract irritation, cough, and hoarseness in occupational exposure. As Iran is one of the biggest carpet producers in the world, this study was carried out to determine the inhalational health risk for employees exposed to VA. To the best of our knowledge, this was the first health risk assessment and the first evaluation of the lung functions and respiratory symptoms in employees exposed to VA. In the six finishing shops of carpet manufacturing industry in Kashan city, Iran the cross-sectional studies were conducted in 2022. The subjects comprised of forty male employees exposed to VA and of forty non-exposed employees in the reference group. VA analyses in the workers' breathing zones were performed based on the National Institute for Occupational Safety and Health (NIOSH) 1453 Method. VA concentrations were measured using Gas Chromatography-Mass Spectrometry (GC-MS). Inhalational risk assessment to VA was performed using the United States Environmental Protection Agency method and the Monte Carlo simulations. Respiratory functions were determined using the spirometry indices. In the exposed employees, considerably higher prevalence rates of pulmonary symptoms were observed in comparison with the control group. Statistical analysis showed a remarkable difference between lung function parameters measured in the case and the control groups. The VA Hazard Quotient (HQ) values for all working posts, except the quality control unit, were > 1 indicating the substantial inhalational non-cancerogenic risk. The sensitivity analysis revealed that the VA concentrations and exposure time had the most significant contribution in the uncertainty assessment. Therefore, it is recommended to decrease exposure to VA concentrations and to reduce the working time of exposed employees.