Skip to main content
PMC home page
British Journal of Industrial Medicine logoLink to British Journal of Industrial Medicine
. 1990 Oct;47(10):656–664. doi: 10.1136/oem.47.10.656

Combined effect of silica dust and tobacco smoking on mortality from chronic obstructive lung disease in gold miners.

E Hnizdo 1
PMCID: PMC1012022  PMID: 2171628

Abstract

A sample of 2209 white South African gold miners aged 45-54 between 1968-71, who started mining exposure during 1936-43, was investigated from 1968-71 to 30 December 1986. The effect of silica dust and tobacco smoking on mortality from chronic obstructive lung disease (COLD) was assessed. The relative risk (RR) for dust exposure before 1950 was estimated as 2.5 (95% confidence interval (CI) 1.5-4.2), for 10 units of 1000 particle-years. The combined effect of dust exposure before 1950 and years of cigarette smoking on mortality from COLD was best estimated by the multiplicative model, indicating that the two exposures act synergistically. All those that died of the disease were smokers. According to the estimates of attributable risk about 5% of the deaths from COLD were from the effect of dust, 34% were from smoking, and 59% were from the combined effect of dust and smoking. In conclusion, the results indicate that workers exposed to silica dust who smoke are at higher risk of dying from COLD than smokers not exposed to silica dust, as the two exposures act synergistically in causing COLD.

Full text

PDF
656

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Armstrong B. K., McNulty J. C., Levitt L. J., Williams K. A., Hobbs M. S. Mortality in gold and coal miners in Western Australia with special reference to lung cancer. Br J Ind Med. 1979 Aug;36(3):199–205. doi: 10.1136/oem.36.3.199. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Becklake M. R., Irwig L., Kielkowski D., Webster I., de Beer M., Landau S. The predictors of emphysema in South African gold miners. Am Rev Respir Dis. 1987 Jun;135(6):1234–1241. doi: 10.1164/arrd.1987.135.6.1234. [DOI] [PubMed] [Google Scholar]
  3. Berry G. Dose-response in case-control studies. J Epidemiol Community Health. 1980 Sep;34(3):217–222. doi: 10.1136/jech.34.3.217. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Breslow N. E., Storer B. E. General relative risk functions for case-control studies. Am J Epidemiol. 1985 Jul;122(1):149–162. doi: 10.1093/oxfordjournals.aje.a114074. [DOI] [PubMed] [Google Scholar]
  5. Bruzzi P., Green S. B., Byar D. P., Brinton L. A., Schairer C. Estimating the population attributable risk for multiple risk factors using case-control data. Am J Epidemiol. 1985 Nov;122(5):904–914. doi: 10.1093/oxfordjournals.aje.a114174. [DOI] [PubMed] [Google Scholar]
  6. Copes R., Thomas D., Becklake M. R. Temporal patterns of exposure and nonmalignant pulmonary abnormality in Quebec chrysotile workers. Arch Environ Health. 1985 Mar-Apr;40(2):80–87. doi: 10.1080/00039896.1985.10545894. [DOI] [PubMed] [Google Scholar]
  7. Davis L. K., Wegman D. H., Monson R. R., Froines J. Mortality experience of Vermont granite workers. Am J Ind Med. 1983;4(6):705–723. doi: 10.1002/ajim.4700040604. [DOI] [PubMed] [Google Scholar]
  8. Finkelstein M., Liss G. M., Krammer F., Kusiak R. A. Mortality among workers receiving compensation awards for silicosis in Ontario 1940-85. Br J Ind Med. 1987 Sep;44(9):588–594. doi: 10.1136/oem.44.9.588. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Frome E. L., Checkoway H. Epidemiologic programs for computers and calculators. Use of Poisson regression models in estimating incidence rates and ratios. Am J Epidemiol. 1985 Feb;121(2):309–323. doi: 10.1093/oxfordjournals.aje.a114001. [DOI] [PubMed] [Google Scholar]
  10. Lubin J. H., Gaffey W. Relative risk models for assessing the joint effects of multiple factors. Am J Ind Med. 1988;13(1):149–167. doi: 10.1002/ajim.4700130110. [DOI] [PubMed] [Google Scholar]
  11. Moolgavkar S. H., Venzon D. J. General relative risk regression models for epidemiologic studies. Am J Epidemiol. 1987 Nov;126(5):949–961. doi: 10.1093/oxfordjournals.aje.a114733. [DOI] [PubMed] [Google Scholar]
  12. Sluis-Cremer G. K., Walters L. G., Sichel H. S. Ventilatory function in relation to mining experience and smoking in a random sample of miners and non-miners in a Witwatersrand Town. Br J Ind Med. 1967 Jan;24(1):13–25. doi: 10.1136/oem.24.1.13. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Whittemore A. S., McMillan A. Lung cancer mortality among U.S. uranium miners: a reappraisal. J Natl Cancer Inst. 1983 Sep;71(3):489–499. [PubMed] [Google Scholar]
  14. Wiles F. J., Faure M. H. Chronic obstructive lung disease in gold miners. Inhaled Part. 1975 Sep;4(Pt 2):727–735. [PubMed] [Google Scholar]
  15. Wyndham C. H., Bezuidenhout B. N., Greenacre M. J., Sluis-Cremer G. K. Mortality of middle aged white South African gold miners. Br J Ind Med. 1986 Oct;43(10):677–684. doi: 10.1136/oem.43.10.677. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from British Journal of Industrial Medicine are provided here courtesy of BMJ Publishing Group

RESOURCES