Chest
Small Airways Disease Induced by Asbestos and Nonasbestos Mineral Dusts
Section snippets
Materials and Methods
We selected 15 asbestos-exposed subjects and 7 nonasbestos dust-exposed subjects in which the lung contained fibrotic and pigmented lesions of the respiratory bronchioles, a change which has been documented early after asbestos exposure in animals. These subjects were matched by age, sex, and smoking history to controls who had no occupational dust exposure. All membranous bronchioles (MB), respiratory bronchioles (RB), and alveolar ducts (AD) were graded for fibrosis, inflammation, and pigment
Results
Of the 22 test patients, 5 were chrysotile miners, 10 were predominantly exposed to amphiboles, 5 were hard-rock miners, 1 worked in a foundry, and 1 as a metal tool fabricator. Morphologically, essentially identical changes were seen with asbestos or nonasbestos dust exposure. Figure 1 illustrates the typical mineral dust-induced lesion of the respiratory bronchiole/alveolar duct. This consists of mural fibrosis with a variable amount of accompanying pigment; the nature of the pigment varies
Discussion
In this study, we have shown that, in workers exposed to a variety of mineral dusts, there exist lesions of small airways which differ morphologically from those seen in pure cigarette smokers. These lesions consist of fibrosis of the respiratory bronchioles and alveolar ducts, often accompanied by pigment. It should be appreciated that in selecting cases for the study, we picked those in which we could find just one such airway, but the grading analysis makes it clear that the lesions are in
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Cited by (5)
Occupationally induced airways obstruction
1996, Medical Clinics of North AmericaChronic obstructive pulmonary disease mortality ir railroad workers
2009, Occupational and Environmental MedicineChronic obstructive pulmonary disease mortality in diesel-exposed railroad workers
2006, Environmental Health PerspectivesExposure and mineralogical correlates of pulmonary fibrosis in chrysotile asbestos workers
1997, Occupational and Environmental MedicineRespiratory disease in non-smoking Western Australian goldminers
1992, British Journal of Industrial Medicine
Supported by grants MT6907 and MA7820 from the Medical Research Council of Canada, and a grant from the National Cancer Institute of Canada.