CHRONIC DIFFUSE INTERSTITIAL FIBROSIS OF THE LUNG IN URANIUM MINERS

\Many uranium miners have been disabled by and died of pulmonary fibro sis that was not recognized as an occupational disease. A review of an imal studies, complications from whole body irradiation, pulmonary fun ction, and mortality studies of uranium miners led us to suspect radia tion-induced chronic diffuse interstitial fibrosis in miners who had i nhaled excessive radon progeny. A selected group of uranium miners (22 ) with severe respiratory disease (but no rounded nodules in chest fil ms) were studied. Lung tissue from five disclosed severe diffuse inter stitial fibrosis, with ''honeycomb lung'' in. all. Some also had small anthrasilicotic nodules and birefringent crystal. Although quartz cry stals probably contributed, we concluded that the predominant injuriou s agent in these cases was alpha particles from radon progeny. This di sease, after a long latent period usually results in pulmonary hyperte nsion, shortness of breath, and death by cardiopulmonary failure.