[Research on the short-term effects of welding fumes on workers' lung function: a panel study]

Objective: To explore the short-term effects of welding fumes on workers' lung function in the welding environment preliminarily, and provide reference for future research. Methods: In October 2020, the lung function of the subjects was repeatedly measured before and after the working shift with a panel study. The paired t test was used to compare the lung function before and after the shift, and the linear mixed effects model was used to analyze the short-term changes of lung function. Results: 36 male welders were included, and the average age was (30.72±5.21) years, average employed year was (4.36±2.17) years. And the average concentration of welding fume was (1.27±0.49) mg/m(3). The forced vital capacity (FVC) , forced expiratory volume in the first second (FEV1) and peak expiratory flow (PEF) of welders after the shift were significantly lower than those before the shift (t=19.52, 48.13, 62.03, P<0.05) . After adjusting the workers' age, BMI and employed years, the changes of FVC% and FEV1% with the concentration of welding fume were statistically significant (β=-1.02, 95%CI: -1.54--0.52; β=-1.56, 95%CI: -1.95--1.16; P<0.01) . In another word, for the 1 mg/m(3) increase of welding fume in the working environment, compared with the baseline, the FVC decreases by 1.02%, and FEV1 decreases by 1.56%. Conclusion: Short-term exposure to welding fumes in workplace can reduce the lung function of welders.