Diffusing Capacity in Bituminous Coal Miners

¹ Appalachian Laboratory for Occupational Respiratory Diseases, National Institute for Occupational Safety and Health and the Department of Medicine, West Virginia School of Medicine, Morgantown

Pulmonary diffusing capacity (D_L) was measured in 133 underground bituminous coal miners at rest and during moderate exercise by the steady state end tidal sampling method. The average D_L among cigarette smoking miners was lower than among nonsmoking miners of comparable age and years of underground mining. In contrast to the smoking miners a large majority of nonsmoking miners had normal D_L. This Difference in D_L could not be explained by the presence of bronchitis, airway obstruction, or rediographic evidence of coal workers' pneumoconiosis (CWP), although bronchitis and CWP were more frequent among the smoking miners. It is doubtful that the measurement of D_L would be a useful screening test for occupational disease among cigarette smoking coal miners, since it is significantly affected by smoking.