Tehran University of Medical Sciences International Journal of Occupational Hygiene 2008-5109 17 1 2025 03 03 19 25 Jamal Biganeh 2. Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Mohammad Javad SheikhMozafari Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Mohammad Hossein Ebrahimi 1. Environmental and Occupational Health Research Center, Shahroud University of Medical Sciences, Shahroud, Iran Mobina Gholipour 1. Environmental and Occupational Health Research Center, Shahroud University of Medical Sciences, Shahroud, Iran Soqrat Omari Shekaftik 2. Department of Occupational Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 2024 10 14 2024 11 11 BACKGROUND: Welding is a process to connect different parts using various techniques. In industrial settings, shielded metal arc welding (SMAW), gas metal arc welding (GMAW), and tungsten inert gas welding (TIG) are the most common types of electric arc welding. In all these procedures, welders are exposed to a range of hazards such as gases and fumes that may affect their pulmonary function and oxidative stress status. This case-control study was conducted to investigate lipid peroxidation, oxidative stress, and pulmonary function status in industrial welders. Method: Case participants worked in one of three types of welding (SMAW, GMAW, TIG) (52 men), and control participants (40 men) were not exposed to welding hazards. Blood biomarkers MDA and TAC were evaluated to determine antioxidant levels, and FVC, FEV1, and FEV1/FVC indices were considered for pulmonary function. Results: The results showed that there was a significant difference in the levels of MDA, FVC, and FEV1 between the welders and the control group, but no significant difference was observed in the levels of TAC. It seems that among welder groups, the mean levels of MDA, FVC, and FEV1 in SMAW welders were significantly different compared to the other groups. Finally, MDA had a significant relationship with all pulmonary indices, and FVC had a significant relationship with all biomarkers of oxidative stress and other pulmonary functions. Conclusion: The findings show that occupational exposure to welding hazards in different types of welding may affect oxidative stress and pulmonary function indices. https://ijoh.tums.ac.ir/index.php/ijoh/article/view/650 https://ijoh.tums.ac.ir/index.php/ijoh/article/download/650/816