Occupational respiratory diseases. Merchant JA, Bochlecke BA, Taylor G, eds. Morgantown, WV: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 86-102, 1986 Sep; :243-285
The literature on silicosis was reviewed and occupational exposures to silicate minerals and resulting health consequences were discussed according to a mineralogical classification scheme. Island structures included: olivine minerals, which were not associated with pneumoconiosis; and kyanite minerals, which were associated with mild fibrosis or pneumoconiosis. Exposure to isolated group structures including, beryl (1302529), cordierite (1302881), and tourmaline (1317937) were not associated with human disease. Chain structures, pyroxenes and amphiboles, were not associated with human disease, and the population at risk for occupational exposure was small. Sheet structures, which comprised the bulk of soil constituents, included: kaolin (1332587), serpentines, pyrophyllite (12269782), talc (14807966), bentonite (1302789), fuller's earth, sepiolite (61180583), mica (12001262), sericite (12174537), and vermiculite (1318009). Among these, occupational exposures to kaolin, pyrophyllite, talc, fuller's earth, sepiolite, mica, or sericite were associated with pneumoconosis. Nearly two thirds of the rocky crust of the earth was composed of framework structures, which included: silica minerals, feldspar, nepheline (12251273), and zeolites. No recognized disease entities were associated with exposure to feldspar or nepheline. Environmental exposure to zeolites was associated with pleural thickening and calcification, and pleural mesotheliomas, but there was no know medical problem related to industrial exposures. The sources of occupational and industrial exposure of each of the silicates, and the epidemiology, pathology, clinical manifestations, diagnostic criteria, and preventive methods for associated lung disease were discussed. Areas in need of research were identified.