Occupational Exposures

Increased respiratory symptoms and airflow obstruction have been suggested as resulting from general exposure to dust at work. Several specific occupational exposures, including coal mining, gold mining, and cotton textile dust, have been suggested as risk factors for chronic airflow obstruction. However, although nonsmokers in these occupations developed some reductions in FEV1, the importance of dust exposure as a risk factor for COPD, independent of cigarette smoking, is not certain. Among workers exposed to cadmium (a specific chemical fume), FEV1, FEV1/FVC, and DLCO were significantly reduced (FVC, forced vital capacity; DLCO, carbon monoxide diffusing capacity of the lung; Chap. 246), consistent with airflow obstruction and emphysema. Although several specific occupational dusts and fumes are likely risk factors for COPD, the magnitude of these effects appears to be substantially less important than the effect of cigarette smoking.