PATTERNS OF COAL WORKERS' PNEUMOCONIOSIS IN APPALACHIAN FORMER COAL M INERS Roscoe C. Young, Jr, MD, Raylinda E. Rachal, MD, Peggy G. Carr, PhD, and Harry C. Press, MD New Orleans, Louisiana and Washington, DC
To aid in diagnostic chest film interpretation of coal workers' pneumoconiosis, a composite profile of common radiologic patterns was developed in 98 Appalachian former coal miners who were diagnosed as having coal miner's pneumoconiosis and who applied for black lung benefits. The mean age was 61 years, with a lifetime coal mine dust exposure of 18.7 years. Results showed that chest radiographs of coal workers' simple pneumoconiosis contained small irregular linear opacities more frequently (47%) than small rounded opacities. Sparse profusion of all small opacities was the rule. Small opacities involved two out of six lung zones simultaneously 39% of the time while other combinations occurred less frequently. Lower zones were involved more frequently than upper ones. Thickened pleura occurred in 18% of radiographs. Other frequent radiographic abnormalities were parenchymal calcifications (19%), marked emphysema (12%), and inactive tuberculosis (12%). Calcification of the aortic knob, a degenerative process reflecting age, occurred in 9%. Only one instance of complicated coal workers' pneumoconiosis (progressive massive fibrosis) was encountered (0.7%). Many of From the College of Pharmacy, Xavier University of Louisiana, New Orleans, Louisiana and the Departments of Psychology and Radiology, Howard University, Washington, DC. Presented as a scientific poster exhibit at the 95th Annual Convention and Scientific Assembly of the National Medical Association, July 28-August 2, 1990, Las Vegas, Nevada. Requests for reprints should be addressed to Dr Roscoe C. Young, Jr, College of Pharmacy, Xavier University of Louisiana, 7325 Palmetto St, New Orleans, LA 70119. JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION, VOL. 84, NO. 1
the descriptive features of coal workers' pneumoconiosis noted in the literature were not observed in this study. Only one instance of complicated pneumoconiosis was encountered. (J NatI Med Assoc. 1992;84:41-48.) Key words * coal miners * pneumoconiosis * chest radiology A uniform international descriptive radiologic classification of pneumoconioses became necessary early in the 20th century, inspired largely by workman's compensation legislation enacted for the protection of disabled or deceased coal miners and their families.' The tendency of asbestos and insulation workers to develop pleural plaques, thickening and calcification of the pleura, "ground glass" pulmonary infiltrates, is a radiologic hallmark of asbestosis. The relationship of asbestos exposure in the development of mesothelioma and bronchogenic carcinoma has been recognized for more than 30 years. Similarly, rock quarry workers, stonecutters, and sandblasters are known to be susceptible to silicosis. Silicosis is characterized by small rounded opacities, large conglomerate nodules, so-called progressive massive fibrosis (PMF), and eggshell nodes on the chest radiograph. Also notable is the tendency of workers with silicosis to develop tuberculosis. On the other hand, the radiologic pattern of coal workers' pneumoconiosis (CWP), although similar in many respects to that of silicosis, has differed sufficiently to be confusing and poorly understood, as the numerous synonyms for the condition would suggest, eg, spurious melanosis,2 coal miners' lung,3 anthracosis,3 silicosis,4 black lung5'6 anthracosilicosis,7 and coal miners' pneu-
moconiosis.8412 41
PATTERNS OF COAL WORKERS' PNEUMOCONIOSIS
1i
Figure 1. Map showing coal mining work sites by state and the approximate number of miners who worked there. In addition to the bituminous mines of western Pennsylvania, Maryland, Virginia, West Virginia, Ohio, Kentucky, Tennessee, and Alabama, miners also worked in southern Illinois, as well as in the anthracite mines of eastern Pennsylvania and in the lignite mines of North Dakota.
Figure 2. Pie chart showing the distribution of small opacities according to type in the lungs of 98 former coal miners with coal workers' pneumoconiosis. Small round opacities up to 10 mm diameter in size or small irregular opacities may be present. Both types may occur together.
developed.
METHODS A retrospective study
was conducted on 98 former coal miners with CWP. They represented 69% of 142 consecutive former coal miners who applied for black
*Available
from ILO Publications Center, 49 Sheridan
42
*q
*--1s
lung benefits in accordance with the Federal Coal Mine Health and Safety Act of 1969 (as amended'3). Miners were seen between 1972 and 1981. They mined coal mainly in Central Appalachian states (Figure 1). Occupational and medical histories were taken. Chest radiographs that conformed with accepted medical standards for interpretation of pneumoconosis were taken.'4"15 Chest radiographs were used to establish the existence of CWP. They were classified in accordance with the International Labor Office/Union Internationale Contra Cancer/Cincinnati 1971 Classification (ILO/ UC) for pneumoconioses.16"17 Each film was interpreted by dual "N' and "B" readers who used ILO/UC standard films* for side-by-side comparison.'2"18
RESULTS
The purpose of this study was to develop a composite profile of common radiologic patterns of CWP. Former coal miners' radiographic studies were used. A percentage aid to diagnostic film interpretation has thus been
Albany, NY 12210; telephone (518) 436-9686.
S.
Figure 3. Graph depicting the frequency of subtypes of small opacities in simple coal workers' pneumoconiosis. Nodules are classified according to the diameter of the predominant opacities: "p" type-round,
To aid in diagnostic chest film interpretation of coal workers' pneumoconiosis, a composite profile of common radiologic patterns was developed in 98 Appalachian former coal miners who were diagnosed as having coal miner's pneumoconiosis and who applied for black lung benefits. The mean age was 61 years, with a lifetime coal mine dust exposure of 18.7 years. Results showed that chest radiographs of coal workers' simple pneumoconiosis contained small irregular linear opacities more frequently (47%) than small rounded opacities. Sparse profusion of all small opacities was the rule. Small opacities involved two out of six lung zones simultaneously 39% of the time while other combinations occurred less frequently. Lower zones were involved more frequently than upper ones. Thickened pleura occurred in 18% of radiographs. Other frequent radiographic abnormalities were parenchymal calcifications (19%), marked emphysema (12%), and inactive tuberculosis (12%). Calcification of the aortic knob, a degenerative process reflecting age, occurred in 9%. Only one instance of complicated coal workers' pneumoconiosis (progressive massive fibrosis) was encountered (0.7%). Many of From the College of Pharmacy, Xavier University of Louisiana, New Orleans, Louisiana and the Departments of Psychology and Radiology, Howard University, Washington, DC. Presented as a scientific poster exhibit at the 95th Annual Convention and Scientific Assembly of the National Medical Association, July 28-August 2, 1990, Las Vegas, Nevada. Requests for reprints should be addressed to Dr Roscoe C. Young, Jr, College of Pharmacy, Xavier University of Louisiana, 7325 Palmetto St, New Orleans, LA 70119. JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION, VOL. 84, NO. 1
the descriptive features of coal workers' pneumoconiosis noted in the literature were not observed in this study. Only one instance of complicated pneumoconiosis was encountered. (J NatI Med Assoc. 1992;84:41-48.) Key words * coal miners * pneumoconiosis * chest radiology A uniform international descriptive radiologic classification of pneumoconioses became necessary early in the 20th century, inspired largely by workman's compensation legislation enacted for the protection of disabled or deceased coal miners and their families.' The tendency of asbestos and insulation workers to develop pleural plaques, thickening and calcification of the pleura, "ground glass" pulmonary infiltrates, is a radiologic hallmark of asbestosis. The relationship of asbestos exposure in the development of mesothelioma and bronchogenic carcinoma has been recognized for more than 30 years. Similarly, rock quarry workers, stonecutters, and sandblasters are known to be susceptible to silicosis. Silicosis is characterized by small rounded opacities, large conglomerate nodules, so-called progressive massive fibrosis (PMF), and eggshell nodes on the chest radiograph. Also notable is the tendency of workers with silicosis to develop tuberculosis. On the other hand, the radiologic pattern of coal workers' pneumoconiosis (CWP), although similar in many respects to that of silicosis, has differed sufficiently to be confusing and poorly understood, as the numerous synonyms for the condition would suggest, eg, spurious melanosis,2 coal miners' lung,3 anthracosis,3 silicosis,4 black lung5'6 anthracosilicosis,7 and coal miners' pneu-
moconiosis.8412 41
PATTERNS OF COAL WORKERS' PNEUMOCONIOSIS
1i
Figure 1. Map showing coal mining work sites by state and the approximate number of miners who worked there. In addition to the bituminous mines of western Pennsylvania, Maryland, Virginia, West Virginia, Ohio, Kentucky, Tennessee, and Alabama, miners also worked in southern Illinois, as well as in the anthracite mines of eastern Pennsylvania and in the lignite mines of North Dakota.
Figure 2. Pie chart showing the distribution of small opacities according to type in the lungs of 98 former coal miners with coal workers' pneumoconiosis. Small round opacities up to 10 mm diameter in size or small irregular opacities may be present. Both types may occur together.
developed.
METHODS A retrospective study
was conducted on 98 former coal miners with CWP. They represented 69% of 142 consecutive former coal miners who applied for black
*Available
from ILO Publications Center, 49 Sheridan
42
*q
*--1s
lung benefits in accordance with the Federal Coal Mine Health and Safety Act of 1969 (as amended'3). Miners were seen between 1972 and 1981. They mined coal mainly in Central Appalachian states (Figure 1). Occupational and medical histories were taken. Chest radiographs that conformed with accepted medical standards for interpretation of pneumoconosis were taken.'4"15 Chest radiographs were used to establish the existence of CWP. They were classified in accordance with the International Labor Office/Union Internationale Contra Cancer/Cincinnati 1971 Classification (ILO/ UC) for pneumoconioses.16"17 Each film was interpreted by dual "N' and "B" readers who used ILO/UC standard films* for side-by-side comparison.'2"18
RESULTS
The purpose of this study was to develop a composite profile of common radiologic patterns of CWP. Former coal miners' radiographic studies were used. A percentage aid to diagnostic film interpretation has thus been
Albany, NY 12210; telephone (518) 436-9686.
S.
Figure 3. Graph depicting the frequency of subtypes of small opacities in simple coal workers' pneumoconiosis. Nodules are classified according to the diameter of the predominant opacities: "p" type-round,
