Emphysema, coal dust directly linked

ATLANTA, July 24 (UPI) -- Coal dust exposure is directly linked to severity of emphysema in smokers and nonsmokers alike, U.S. researchers found.

The study findings, reported in the Journal of Respiratory and Critical Care Medicine, said cumulative exposure to coal mine dust was a highly significant predictor of emphysema severity after accounting for cigarette smoking, age at death and race.

Lung tissue analysis corroborated these findings -- the greater the concentration of coal dust in the lungs, the more severe the emphysema.

Not surprisingly, the researchers said, emphysema was also more severe among smokers than never smokers in both miners and non-miners and mine dust exposure and cigarette smoking had similar, additive effects on emphysema severity.

"In this study we have shown that coal mine dust exposure is a significant predictor of emphysema severity," study lead author Eileen Kuempel of the National Institute for Occupational Safety and Health, part of the Centers for Disease Control and Prevention, said in a statement.