Accelerated silicosis in workers exposed to agate dust in Guangzhou, China

Background An investigation of a small private agate mill was prompted by a n agate worker who presented with silicosis in Guangzhou, China, in Decembe r 1998. Methods The work processes and records of dust measurements of the mill wer e examined. The mean total dust concentrations ranged from 3.0 to 9.9 mg/m( 3); 86-88% of the particles' diameter was smaller than 5.0 mum. Free SiO2 c ontent from agate samples was measured. Occupational history was obtained a nd X-ray, chest and lung function was carried out. Results Free SiO2 content of the agate was 90.5%. Thirty-two men involved i n processing agate stone were examined. The mean (+/- SD) age was 29.8 (+/- 4.9) years and the mean (+/- SD) duration of exposure was 3.5 (+/-1.7) year s. Fifteen cases (47%) were diagnosed as accelerated silicosis. Up to Septe mber 1999, three had died from respiratory failure and five were in critica l condition. Conclusion Silicosis is an important problem in primitive work environments. (C) 2001 Wiley-Liss, Inc.