Respiratory function and bronchial responsiveness among industrial workers exposed to different classes of occupational agents: a study from Algeria

The study group totalled 546 male subjects of whom 114 were exposed to welding fumes, 106 to solvents, 107 to mineral dust, 97 to organic dust and 123 without known exposure to airway irritants. A questionnaire was administered and spirometry and bronchial responsiveness to histamine were assessed by one observer, in the morning before work to prevent effects of acute exposure.The mean (SD) age of the participants was 39.3 (7.8) years, with a mean duration of employment of 13.8 (6.6) years. Both before and after adjustment for smoking status, forced expiratory volume in 1 second (FEV1, expressed as % predicted) was lower in welders -4.0% (95% confidence interval [CI], -6.3 to -1.8; p = 0.01) and workers exposed to solvents -5.6% (CI: -7.9 to -3.3; p = 0.0009) than in control subjects. Furthermore, solvent workers had an odds ratio of 3.43 (95% CI: 1.09–11.6; p = 0.037) for bronchial hyperresponsiveness compared with the reference group.The higher prevalence of bronchial hyperresponsiveness in solvent workers adds to the growing body of evidence of adverse respiratory effects of occupational solvent exposure. These results point to the necessity of preventive measures in solvent workers to avoid these adverse respiratory effects.Although the dominant cause of chronic obstructive pulmonary disease (COPD) is cigarette smoking, there is little doubt that chronic occupational exposures to various agents contribute to the incidence and the severity of chronic airways disease, including COPD [1-4]. The quantitative contribution of occupational factors to the burden of COPD morbidity or mortality has been recently estimated at about 15% [5]. This value corresponds to the median of the attributable fractions of occupation to the occurrence of COPD, as derived from published population studies or occupational cohort studies.These studies have been mainly concerned with occupational exposures to mineral dusts (in mines, metal industries or construction) or to organic dusts (in