Effects of Simultaneous Exposure to Smoking and Welding Fume on Pulmonary Function Tests in Spot Welders

Background: The respiratory effects of fume exposure during spot welding may aggravate some environmental risk factors such as tobacco smoking. Fume exposure and smoking have negative effects on pulmonary function tests (PFTs). This study assessed the simultaneous effects of smoking and welding fume on spirometry tests in spot welders. Materials and Methods: This cross-sectional study was conducted on 667 spot welders and 1000 assemblers in an automotive manufacturing plant. Spirometry was carried out on all the participants under standard conditions and according to the American Thoracic Society Clinical Practice Guidelines and indices including FEV1, FVC, FEV1/FVC, FEF 25-75, and PEF were measured and compared between two groups of the study population including workers of spot welding and assembling. Results: It was found that the effect of simultaneous exposure to smoking and welding fume was aggravated on the PFT indices including the FEV1 percent, FEV1/FVC, the FEV1/FVC percent, the PEF percent, FEF25-75, and the FEF25- 75 percent, but not on indices such as FVC, the FVC percent, and PEF. Conclusion: Simultaneous exposure to smoking and welding fume resulted in a reduction in some spirometry indices, causing respiratory airway obstruction in the spot welders. Occupational safety and regular medical examinations with shorter intervals in smoking spot welders can prevent acute respiratory effects of exposure to smoking and welding fume.