title: Accelerated silicosis in workers exposed to agate dust in Guangzhou, China.
abstract: BACKGROUND
  An investigation of a small private agate mill was prompted by an agate worker who presented with silicosis in Guangzhou, China, in December 1998.
  
  
  METHODS
  The work processes and records of dust measurements of the mill were examined. The mean total dust concentrations ranged from 3.0 to 9.9 mg/m3; 86-88% of the particles' diameter was smaller than 5.0 microm. Free SiO2 content from agate samples was measured. Occupational history was obtained and X-ray chest and lung function was carried out.
  
  
  RESULTS
  Free SiO2 content of the agate was 90.5%. Thirty-two men involved in 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) years. Fifteen cases (47%) were diagnosed as accelerated silicosis. Up to September 1999, three had died from respiratory failure and five were in critical condition.
  
  
  CONCLUSIONS
  Silicosis is an important problem in primitive work environments.
authors: Guangzhou Occupational Diseases Prevention and Treatment Centre, Guangzhou, People's Republic of China. jcqiang@21cn.com
authors: C Q
authors: CQ
authors: Jiang
authors: L W
authors: LW
authors: Xiao
authors: T H
authors: TH
authors: Lam
authors: N W
authors: NW
authors: Xie
authors: C Q
authors: CQ
authors: Zhu
mesh_terms: D000328:Adult; D002681:China / Q000453:epidemiology; D004391:Dust / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008906:Mining; D011791:Quartz / Q000009:adverse effects*; D015656:Respiratory Mechanics; D012306:Risk; D012829:Silicosis / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D013997:Time Factors
chemical_list: D004391:Dust; D011791:Quartz