Article Text

Download PDFPDF

Original article
A 37-year observation of mortality in Chinese chrysotile asbestos workers
  1. Xiaorong Wang1,
  2. Eiji Yano2,
  3. Hong Qiu1,
  4. Ignatius Yu1,
  5. Midori N Courtice1,
  6. L A Tse1,
  7. Sihao Lin1,
  8. Mianzhen Wang3
  1. 1Division of Occupational and Environmental Health, School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China
  2. 2School of Public Health, Teikyo University School of Medicine, Tokyo, Japan
  3. 3Department of Occupational Health, Huaxi School of Public Health, Sichuan University, Chengdu, China
  1. Correspondence to Professor Xiaorong Wang, School of Public Health and Primary Care, The Chinese University of Hong Kong, 4/F School of Public Health, Prince of Wales Hospital, Shatin, N.T., Hong Kong SAR, China; xrwang{at}


Objectives This 37-year prospective cohort study was undertaken to provide additional evidence for mortality risks associated with exposure to chrysotile asbestos.

Methods 577 asbestos workers and 435 control workers in original cohorts were followed from 1972 to 2008, achieving a follow-up rate of 99% and 73%, respectively. Morality rates were determined based on person-years of observation. Cox proportional hazard models were constructed to estimate HRs of cause-specific mortality, while taking into account age, smoking and asbestos exposure level.

Results There were 259 (45%) deaths identified in the asbestos cohort, and 96 died of all cancers. Lung cancer (n=53) and non-malignant respiratory diseases (n=81) were major cause-specific deaths, in contrast to nine lung cancers and 11 respiratory diseases in the controls. Age and smoking-adjusted HRs for mortality by all causes and all cancers in asbestos workers were 2.05 (95% CI 1.56 to 2.68) and 1.89 (1.25 to 2.87), respectively. The risks for lung cancer and respiratory disease deaths in asbestos workers were over threefold that in the controls (HR 3.31(95% CI 1.60 to 6.87); HR 3.23 (95% CI 1.68 to 6.22), respectively). There was a clear exposure–response trend with asbestos exposure level and lung cancer mortality in both smokers and non-smokers.

Conclusion Data from this prospective cohort provide strong evidence for increased mortality risks, particularly from lung cancer and non-malignant respiratory diseases, associated with exposure to chrysotile asbestos, while taking into account of the smoking effect.

  • Chrysotile asbestos
  • asbestos textile workers
  • mortality
  • lung cancer
  • China
  • prospective cohort
  • asbestos-induced lung disease
  • mesothelioma
  • occupational lung disease
  • tuberculosis
  • asthma epidemiology
  • COPD epidemiology

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • See Editorial, p 98

  • Funding This study was funded by the Pneumoconiosis Compensation Funding Board, Hong Kong SAR, China.

  • Competing interests None declared.

  • Ethics approval Ethics approval was provided by the Research Ethics Committee of the Chinese University of Hong Ko.

  • Provenance and peer review Not commissioned; externally peer reviewed.

Linked Articles