Silicosis and pulmonary tuberculosis in stone-grinding factories in Saraburi, Thailand.

The stone-grinding industry is well known to place its workforce at higher risk for silicosis. In addition, workers who are exposed to silica fibers are at a higher risk for pulmonary tuberculosis. This study was conducted to determine the prevalence levels of silicosis and pulmonary tuberculosis among workers in 33 factories in 3 subdistricts of Saraburi, Thailand and the associated risk factors. Thirty-one of the factories (93.9%) had amounts of either total dust or respirable dust exceeding threshold limit values with the average levels of total dust and respirable dust of 24.3 +/- 34.6 and 2.4 +/- 1.6 mg/m3 respectively. Radiologic patterns indicated that 61 workers (9.0%) had silicosis and 13 workers (1.9%) had pulmonary tuberculosis. The prevalence of silicosis and pulmonary tuberculosis was significantly associated with years of work. This study demonstrated the need for developing and supporting potential primary preventive intervention, periodic medical screening as a part of a medical surveillance system and a national occupational medical services program.