Lung diseases caused by the inhalation of mineral particles, fibers, and fumes present a changing problem for modern industry. Dust controls, industrial hygiene, and government regulations in the industrialized nations have decreased exposures to the materials, such as silica, asbestos, coal, or talc that cause the traditional pneumoconioses. Lung diseases caused by beryllium, cobalt, and other metals may be increasing in modern industry. These metal diseases are caused by sensitization and a subsequent T-lymphocyte-mediated immune response to the metals, and strike a minority of exposed workers who carry specific genetically determined HLA class II and T-cell antigen receptor alleles. Substantial or slightly increased risks for lung cancer have been associated with exposure to virtually all of these minerals. The pneumoconioses represent an increasing problem in developing countries where the extraction and processing of raw materials are growing but industrial hygiene measures are not in place.