Pulmonary diseases associated with exposure to silica (7631869) and nonfibrous silicate minerals were reviewed by the Silicosis and Silicate Disease Committee, National Institute for Occupational Safety and Health. Topics included the history of silicosis, the mineralogy of silica and the silicates, pathogenesis of silicosis, accelerated silicosis, chronic silicosis, silicotic nodules, pleural and subpleural lesions, intrapulmonary lesions, interstitial fibrosis, rheumatoid pneumoconiosis (Caplan's lesion), silicotic nodules in lymph nodes and nonpulmonary tissues, vascular changes in silicotic lungs, emphysema and its relationship to silicosis, radiologic features of silicosis, clinical features of chronic silicosis, silicate induced lung disease (silicatosis), mixed dust fibrotic nodule, radiologic features of silicatosis, relationship between silica and bronchogenic carcinoma, the relationship between scleroderma and rheumatoid arthritis in occupational populations exposed to silica, and the occurrence of nephropathy in workers exposed to silica. Morphological studies of pulmonary lesions utilizing light and polarized light microscopy were described. Analytical methods for examining pulmonary lesions were summarized. Regulating exposure to silica and nonfibrous silicates was discussed.