Silica, silicosis and lung-cancer: results from a cohort study in the stone and quarry industry

  • K. UlmEmail author
  • P. Gerein
  • J. Eigenthaler
  • S. Schmidt
  • H. Ehnes
Original Article



Workers compensated for silicosis outside the mining industry are at an increased risk of developing lung cancer. In the meta-analyses no data from Germany are involved. Furthermore, exposure data are necessary if a threshold value is to be assessed in order to reduce the risk for silicosis and also for lung cancer.


A cohort study among workers compensated for silicosis between 1988 and 2000 from the stone and quarry industry in Germany has been initiated. The cohort was followed up until the end of 2001. From all workers a detailed description of their jobs was assessed.


Four hundred and forty workers were enrolled in the study. During the follow-up 144 workers died, compared with 74.35 expected cases based on the mortality rates of the general population from Germany, leading to a standard mortality ratio (SMR) of 1.94 (95% CI 1.63–2.28). Lung cancer was the cause of death in 16 cases (SMR 2.40; 95% CI 1.37–3.90). All workers had a peak exposure above 0.15 mg/m3, the current threshold value. The cumulative exposure was above 2 mg/m3·years and the average exposure was 0.10 mg/m3 or larger. No association between the exposure and the risk of developing lung cancer could be observed.


Workers from the stone and quarry industry compensated for silicosis are at an increased risk of developing lung cancer. In order to reduce that risk, the exposure has to be lowered, with a peak exposure below 0.15 mg/m3 and an average exposure below 0.10 mg/m3.


Silicosis Lung cancer Cohort-study Silica exposure 


  1. 1.
    Silicosis and Silicate Disease Committee (1988) Diseases associated with exposure to silica and nonfibrous silicate minerals. Arch Pathol Lab Med 112:673–720PubMedGoogle Scholar
  2. 2.
    International Agency for Research on Cancer (1997) IARC monographs on the evaluation of carcinogenic risks to humans, silica, some silicates, coal dust and para-aramide fibrils, p 68Google Scholar
  3. 3.
    American Conference of Governmental Industrial Hygienists (ACGIH) (1999) Silica, CrystallineGoogle Scholar
  4. 4.
    Greim H (ed) (1999) Gesundheitsschädliche Arbeitsstoffe. SilicumdioxidGoogle Scholar
  5. 5.
    Smith AH, Lopipero PA, Barroga VR (1995) Meta-analysis of studies of lung cancer among silicotics. Epidemiology 6:617–624PubMedGoogle Scholar
  6. 6.
    Steenland K, Stayner L (1997) Silica, asbestos, man-made mineral fibers, and cancer, Cancer Causes Control 8:491–503Google Scholar
  7. 7.
    Mehnert WH, Staneczek W, Mohner M, Konetzke G, Muller W, Ahlendorf W, Beck B, Winkelmann R, Simonato L (1990) A mortality study of a cohort of slate quarry workers in the German Democratic Republic, IARC Sci Publ 97:55–64Google Scholar
  8. 8.
    Dong D, Xu G, Sun Y, Hu P (1995) Lung cancer among workers exposed to silica dust in Chinese refractory plants. Scand J Work Environ Health 21 [Suppl 2]:69–72Google Scholar
  9. 9.
    Ulm K, Waschulzig B, Ehnes H, Guldner K, Thomasson B, Schwebig A, Nuss H (1999) Silica dust and lung cancer in the German stone, quarrying, and ceramics industries: results of a case–control study. Thorax 54:347–351PubMedGoogle Scholar
  10. 10.
    Checkoway H, Hughes JM, Weill H, Seixas NS, Demers PA (1999) Crystalline silica exposure, radiological silicosis, and lung cancer mortality in diatomaceous earth industry workers. Thorax 54:56–59PubMedGoogle Scholar
  11. 11.
    Steenland K, Mannetje A, Boffetta P, et al (2001) Pooled exposure-response and risk assessment for lung cancer in 10 cohorts of silica-exposed workers: an IARC multi-centric study. Cancer Causes Controls 12:773–784CrossRefGoogle Scholar
  12. 12.
    Checkoway H, Franzblau A (2000) Is silicosis required for silica-associated lung cancer? Am J Ind Med 37:252–259CrossRefPubMedGoogle Scholar
  13. 13.
    Finkelstein MM (2000) Silica, silicosis, and lung cancer: a risk assessment. Am J Ind Med 38:8–18CrossRefPubMedGoogle Scholar
  14. 14.
    Rice FL, Park R, Stayner L, Smith R, Gilbert S, Checkoway H (2001) Crystalline silica exposure and lung cancer mortality in diatomaceous earth industry workers: a quantitative risk assessment. Occup Environ Med 58:38–45CrossRefPubMedGoogle Scholar
  15. 15.
    Checkoway H, Rice CH (1992) Time-weighted averages, peaks, and other indices of exposure in occupational epidemiology. Am J Ind Med 21:25–33PubMedGoogle Scholar
  16. 16.
    Breslow NE, Day NE (1987) Statistical methods in cancer research: volume II—the design and analysis of cohort studies. In: Heseltine E (ed) IARC Scientific Publications No. 82Google Scholar
  17. 17.
    Ulm K (1990) A simple method to calculate the confidence interval of a standardized morality ratio (SMR). Am J Epidemiol 131:373–375PubMedGoogle Scholar
  18. 18.
    Cox DR (1972) Regression models and life-tables. J R Stat Soc 34:187–220Google Scholar
  19. 19.
    Hastie TJ, Tibshirani RJ (1995) Generalized additive models for medical research. Stat Methods Med Res 4:187–196PubMedGoogle Scholar
  20. 20.
    Royston P, Altman DG (1994) Regression using fractional polynomials of continuous covariates: parsimonious parametric modeling. Appl Stat 43:429–467Google Scholar
  21. 21.
    Axelson O, Steenland K (1988) Indirect methods of assessing the effects of tobacco use in occupational studies. Am J Ind Med 13:105–118PubMedGoogle Scholar
  22. 22.
    Finkelstein MM (2000) Silica, silicosis, and lung cancer: a risk assessment. Am J Ind Med 38:8–18CrossRefPubMedGoogle Scholar
  23. 23.
    Greaves IA (2000) Not-so-simple silicosis: a case for public health action. Am J Ind Med 37:245–251CrossRefPubMedGoogle Scholar
  24. 24.
    Ulm K (2002) Risk assessment between silica dust and lung cancer. Cancer Causes Controls 13:779–780CrossRefGoogle Scholar
  25. 25.
    Rice FL (2001) Crystalline silica exposure and lung cancer mortality in diatomaceous earth industry workers. Occup Environ Med 58:38–45CrossRefPubMedGoogle Scholar
  26. 26.
    Buchanan D, Miller BG, Soutar CA (2003) Quantitative relations between exposure to respirable quartz and risk of silicosis. Occup Environ Med 60:159–164CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  • K. Ulm
    • 1
    Email author
  • P. Gerein
    • 1
  • J. Eigenthaler
    • 2
  • S. Schmidt
    • 2
  • H. Ehnes
    • 2
  1. 1.Institute for Medical Statistics and EpidemiologyTechnical University of MunichMunichGermany
  2. 2.Steinbruchs-BGLangenhagenGermany

Personalised recommendations