Pulmonary function and symptoms of welders.

OBJECTIVE As the findings on changes in pulmonary function of welders have been inconsistent, this study aimed to analyze respiratory symptoms and pulmonary function among welders and controls with particular emphasis on small airways dysfunction. METHODS Cross-sectional analysis, using spirometry and a standardized questionnaire, was used to evaluate 521 participants, 166 of whom (64 welders and 102 controls) were evaluated for pulmonary symptoms, occupational inhalative exposures, leisure time activities, and anamnestic data. RESULTS The welders reported more pulmonary symptoms than the controls. They exhibited a decreased mean expiratory flow (MEF) at 25% and 50% of vital capacity (MEF25, MEF50) while the other parameters tested (forced vital capacity, forced expiratory volume in 1 s) were unchanged compared with the controls. Multivariate regression analysis revealed that smoking explained the observed variance; only in MEF25 the duration of welding exposure had a significant influence on this parameter. CONCLUSIONS The significantly reduced flow values among the welders compared with the controls indicates the presence of small airways disease. Differences in smoking habits accounted for more than double the differences in MEF25 than did chronic welding fume exposure, confirming the role of the former as the main risk factor leading to the decline in lung function. Longitudinal studies are needed to evaluate the long-term effects of chronic welding fume exposure, in particular with a view to identifying especially susceptible workers.