Coal mine dust exposure and type of pulmonary emphysema in coal workers

The relationship between coal mining and type of emphysema was investigated in 266 autopsied coal miners from Southern West Virginia and 75 nonminer controls. Information on years of mining, cigarette smoking and age was available in all cases. Emphysema was graded for severity on whole lung sections and typed into centriacinar, focal, panacinar, bullous, scar, paraseptal and senile. Pneumoconiosis was graded using standardized protocols. There were significant relationships between coal mining, severity of pneumoconiosis, coal dust in the lungs and grade of emphysema. An additive effect of cigarette smoking and coal mining was evident. The most common type of emphysema in both miners and controls was centriacinar (including focal) emphysema. All types of emphysema, except senile, were more common in miners than nonminers and in smokers compared to nonsmokers. Mineral dust content was greatest in those with centriacinar emphysema, whereas coal and silica were greatest in those with scar and panacinar emphysema. We conclude that all major types of emphysema are associated with coal mine dust exposure and that the composition of the dust and form of the pneumoconiosis may influence the type of emphysema.