Lung volumes in working coal miners.
Morgan WK; Seaton A; Burgess DB; Lapp NL; Reger R
Ann NY Acad Sci 1972 Dec; 200(1):478-493
Since pulmonary overdistension may play a role in producing respiratory disability in coal miners, the effect of increasing radiographic category, according to the UICC classification of pneumoconiosis, on lung volumes was investigated. After ascertaining that Barnhard's radiographic method gave acceptable results in the determination of lung volumes, regression equations were used for determining predicted residual volume (RV), total lung capacity (TLC), and the ratio RV/TLC. More than 2000 working anthracite and bituminous coal miners were studied. The subjects were divided into six groups based on presence or absence of airway obstruction and of radiographic categorization of their simple coal workers pneumoconiosis (CWP). RV increased with radiographic category regardless of the presence of obstructive airway disease. The presence of obstruction had an additional effect, so that the largest increases in RV were found in miners with both obstruction and pneumoconiosis. Several possible explanations are presented for the significantly greater than predicted observed mean RV in nonobstructed miners; the authors favor the explanation that CWP is associated with an increase in resistance in flow in the distal airways. The upward trend of RV with radiographic category was not related to smoking habits, except that the ratio of observed to predicted RV in each category was higher for smokers than for nonsmokers.
NIOSH-Author; Radiographic-analysis; Coal-miners; Coal-dust; Coal-workers-pneumoconiosis; Airway-obstruction; Chest-X-rays; X-ray-diagnosis; Occupational-respiratory-disease; Air-flow; Lung-disorders; Pulmonary-function-tests; Pulmonary-function
Selikoff IJ; Key MM; Lee DH
Annals of the New York Academy of Sciences, Vol. 200, Coal Workers' Pneumoconiosis