Radiographical appearance of talcosis and composition of talc.
Zhao-J; Li-Z; Liu-J; Du-Y; Wang-R
NIOSH 1990 Nov; :846-851
The results of a study of talcosis in workers exposed to talc (14807966) were discussed. Industrial hygiene monitoring data for a facility in the China consisting of a talc mine, mill, and talc carving factory were summarized. Dust concentrations at the facility ranged from 68 to 5561mg/m3 in the 1950s and 1960s. Although dust control measures were implemented in the 1970s dust concentrations on the order of 50 to 395mg/m3 still occur at the facility. Most of the dusts consisted of particles having diameters below 5 microns. The free silica (14808607) content of the dust ranged from 0.95 to 2.87%. A mineralogical analysis of the ore processed indicated that it was essentially pure talc containing small amounts of serpentine, phosphorite, and quartz as impurities. No fibrous or asbestiform minerals were detected. Ninety seven cases of talcosis (70 in males) were diagnosed at the facility since 1958. Eighty occurred in the miners and 17 in employees at the talc carving factory. Twenty four cases were complicated by tuberculosis. Irregular small opacities were the typical radiographic features of the cases. Reticulate and nodular opacities predominated in early stage talcosis. Large shadows in the lung fields were seen in late stage talcosis. Enlarged hilar lung nodes were usually not observed. The authors conclude that the studied worker population was exposed to pure talc. The X-ray manifestations of talcosis resemble those of silicosis.
Epidemiology; Respiratory-system-disorders; Mining-industry; Mineral-dusts; Occupational-exposure; Chemical-analysis; Chest-X-rays
Infectious Diseases; Disease and Injury; Asthma and Chronic Obstructive Pulmonary Disease; Respiratory-system-disorders;
Proceedings of the VIIth International Pneumoconioses Conference