Radiographic findings from the National Institute for Occupational Safety and Health (NIOSH), Enhanced Coal Workers' Health Surveillance Program (ECWHSP)--2005-2009

Objective: Geographic clustering of a rapidly progressing form of coal workers' pneumoconiosis (CWP) was recently reported. NIOSH sought to better define the scope and magnitude of the problem, and identify plausible causes to facilitate prevention of occupational respiratory disease among coal miners.

Methods: Between 2005 and 2009, the NIOSH-administered ECWHSP utilized a mobile examination unit to obtain chest radiographs (CXRs) from US coal miners. NIOSH B Readers interpreted the CXRs according to the International Labour Office Classification of Radiographs of Pneumoconioses.

Results: A total of 6,658 miners from 15 states provided CXRs. The prevalence of CWP was higher in a three state region (Kentucky: 9.0%, Virginia: 8.0%, and West Virginia: 4.8%), compared to the 12 other coal mining states (RR=4.1; 95% CI=3.0¨C5.5). Miners in these three states had high rates of r-type opacities on their CXRs (RR=7.3; 95% CI=3.7¨C14.6), advanced CWP (small opacity profusion ≥2/1, RR=7.7; 95% CI=3.7¨C16.0), and progressive massive fibrosis (PMF, the most severe form of CWP, RR=10.0; 95% CI=3.6¨C27.8). Irrespective of mining region, workers currently at mines with fewer than 100 employees had a higher prevalence of CWP, PMF, r-type opacities, and advanced CWP, compared to mines with 100 or more employees.

Conclusion: Results from the NIOSH ECWHSP confirm the ongoing elevated prevalence of severe forms of CWP among Appalachian bituminous coal miners, and also the increased burden of disease among miners currently working in smaller mines. Coal miner dust exposures must be reduced to address the continuing problem of occupational lung disease.