Mineralogical and exposure determinants of pulmonary fibrosis among Québec chrysotile miners and millers

  • Ataollah Nayebzadeh
  • Bruce W. Case
  • Janick Massé
  • André Dufresne
Original Article


Objectives: Lung fibre content was determined for 86 former chrysotile miners and millers in two Québec mining regions: Thetford mines (TM) and the Asbestos region (AR). Methods: Fibres were assessed using transmission electron microscopy (TEM) and energy dispersive X-ray spectrometry (EDS). Asbestos body (AB) concentrations were assessed by microscopy of tissue digests. Corresponding histological lung tissue sections were quantitatively graded for the severity of interstitial fibrosis on a 12-point scale. Fibrosis score and its associations with (1) fibre concentrations and fibre dimensions within three fibre length intervals (less than 5 μm, 5–10 μm, and over 10 μm), and (2) several exposure variables were evaluated using correlation coefficients and regression techniques. Results: Concentration of short (<5 μm) tremolite fibres was the best predictor of fibrosis grade in both mining groups (r=0.44, P<0.01 and r=0.39, P<0.01 for TM and AR, respectively). Chrysotile fibre concentration showed a lower correlation with the fibrosis grade for subjects from TM only. Long (>10 μm) amosite fibre concentration showed a linear relationship with the fibrosis score in miners and millers from AR. Exposure variables, including smoking, had no predictive value for fibrosis grade. Within fibre length categories, fibre dimension was not related to the fibrosis score. Conclusion: Lung fibre concentration as measured by TEM/EDS, especially that of short (<5 μm) tremolite fibres, is a better predictor of fibrosis grade in these two groups of chrysotile miners than either the concentration of ABs or the duration of exposure. Due to the limitation of our counting method, almost all fibres longer than 10 μm observed in this study were shorter than 14 μm. Thus, if length plays a role in fibrogenesis, it may be related to fibres of greater length than those covered in this study.


Tremolite Chrysotile Pulmonary fibrosis Asbestosis 



This study was funded in part by National Science Engineering Research Council (NSERC Canada, grant # IOR 191695) and by Medical Research Council (MRC Canada, grant # 13739).


  1. Adamson IYR, Bowden DH (1987a) Response of mouse lung to crocidolite. 1. Minimal fibrotic reaction to short fibres. J Pathol 152:99–107CrossRefPubMedGoogle Scholar
  2. Adamson IYR, Bowden DH (1987b) Response of mouse lung to crocidolite asbestos. 2. Pulmonary fibrosis after long fibres. J Pathol 152:109–117CrossRefPubMedGoogle Scholar
  3. Albin M, Johansson L, Pooley FD, Jakobsson K, Attewell R, Mitha R (1990) Mineral fibres, fibrosis, and asbestos bodies in lung tissue of deceased asbestos cement workers. Br J Ind Med 47:767–774PubMedGoogle Scholar
  4. Case BW (1994) Biological indicators of chrysotile exposure. Ann Occup Hyg 38(4):503–518PubMedCrossRefGoogle Scholar
  5. Case BW, Dufresne A (1997) Asbestos, asbestosis and lung cancer: observations in Québec chrysotile workers. Environ Health Perspect 105(Suppl 5):1113–1119PubMedCrossRefGoogle Scholar
  6. Case BW, Dufresne A, McDonald AD, McDonald JC, Sébastien P (2000) Asbestos fibre type and length in lungs of chrysotile textile and production workers: fibres longer than 18 μm. Inhal Toxicol 12(9 Suppl 3):411–418CrossRefGoogle Scholar
  7. Churg A (1983) Asbestos content of the lung in patients with and without airways disease. Am Rev Respir Dis 127:470–473PubMedGoogle Scholar
  8. Churg A, Vedal S (1994) Fibre burden and pattern of asbestos-related disease in workers with heavy mixed amosite and chrysotile exposure. Am J Respir Crit Care Med 150:663–669PubMedGoogle Scholar
  9. Churg A, Wiggs B, Depaoli L, Kampe B, Stevens B (1984) Lung asbestos content in chrysotile workers with mesothelioma. Am Rev Res Dis 130:1042–1045Google Scholar
  10. Churg A, Wright JL, Depaoli L, Wiggs B (1989) Mineralogic correlates of fibrosis in chrysotile miners and millers. Am Rev Respir Dis 139:891–896PubMedGoogle Scholar
  11. Churg A, Wright J, Wiggs B, Deapooli L (1990) Mineralogical parameters related to amosite asbestos-induced fibrosis in humans. Am Rev Respir Dis 142:1331–1336PubMedGoogle Scholar
  12. Churg A, Wright JL, Vedel S (1993) Fibre burden and patterns of asbestos-related diseases in chrysotile miners and millers. Am Rev Respir Dis 148:25–31PubMedGoogle Scholar
  13. Craighead JE, Abraham JL, Churg A, Green FH, Kleinerman J, Pratt PC, Seemayer PC, Vallyathan V, Weill H (1982) The pathology of asbestos associated diseases of the lungs and pleural cavities. Diagnostic criteria and proposed grading scheme (Report of the pneumoconiosis committee of the College of American Pathologists and the National Institute for Occupational Safety and Health). Arch Pathol Lab Med 106:544–596PubMedGoogle Scholar
  14. Dufresne A, Case B, Fraser R, Siemiatycki J, Takahashi K, Perrault G (1994) Decoding occupational exposure history from total lung tissue analysis: concordance between physico-chemical analysis and occupational histories. Ann Occup Hyg 38(Suppl 1):469–482PubMedGoogle Scholar
  15. Finkelstein MM, Dufresne A (1999) Inferences on the kinetics of asbestos deposition and clearance among chrysotile miners and millers. Am J Ind Med 35(4):401–412CrossRefPubMedGoogle Scholar
  16. Gibbs GW, Lachance M (1972) Dust exposure in the chrysotile asbestos mines and mills in Québec. Arch Environ Health 24:189–197PubMedGoogle Scholar
  17. Green FHY, Harley R, Vallyathan V, Althouse R, Fick G, Dement J, Mitha R, Pooly F (1997) Exposure and mineralogical correlates of pulmonary fibrosis in chrysotile asbestos workers. Occup Environ Med 54:549–559PubMedCrossRefGoogle Scholar
  18. Liddell D (1991) Mineral fibres and health. CRC Press, Boca Raton, FLGoogle Scholar
  19. McDonald JC, Liddell FDK, Gibbs GW, Eyssen GE, McDonald AD (1980) Dust exposure and mortality in chrysotile mining 1910–1975. Br J Ind Med 37:11–24PubMedGoogle Scholar
  20. McDonald JC, Liddell FDK, Dufresne A, McDonald AD (1993) The 1891–1920 birth cohort of Québec chrysotile miners and millers mortality 1976–88. Br J Ind Med 50:1073–1081PubMedGoogle Scholar
  21. McDonald AD, Case BW, Churg A, Dufresne A, Gibbs GW, Sebastien P, McDonald JC (1997) Mesothelioma in Québec chrysotile miners and millers: epidemiology and aetiology. Ann Occup Hyg 41(6):707–719CrossRefPubMedGoogle Scholar
  22. McDonald JC, McDonald AD, Hughes JM (1999) Chrysotile, tremolite and fibrogenicity. Ann Occup Hyg 43(7):439–442CrossRefPubMedGoogle Scholar
  23. Miller BG, Jones AD, Searl A, Buchanan D, Cullen RT, Soutar CA, Davis JM, Donalldson K (1999a) Influence of characteristics of inhaled fibres on development of tumors in rat lung. Ann Occup Hyg 43(3):167–179CrossRefPubMedGoogle Scholar
  24. Miller BG, Searl A, Davis JMG, Donaldson K, Cullen RT, Botton RE, Buchanan D, Soutar CA (1999b) Influence of length, dissolution and biopersistence on the production of mesothelioma in the rat peritoneal cavity. Ann Occup Hyg 43(3):155–165CrossRefPubMedGoogle Scholar
  25. Minitab Inc. (1995) Minitab user’fibres guide Release 10 XtraGoogle Scholar
  26. Nayebzadeh A, Dufresne A, Case BW, Vali H, Williams-Jones AE, Martin R, Normand C, Clarck J (2001) Lung mineral fibres of former miners and millers from Thetford-mines and Asbestos regions: a comparative study of concentration and dimension. Arch Environ Health 56:65–76PubMedCrossRefGoogle Scholar
  27. Roggli VL (1989) Pathology of human asbestosis: a critical review. Advances in pathology, vol 2. Year Book, Chicago, ILGoogle Scholar
  28. Roggli VL (1990) Human diseases consequences of exposures: a review of human lung pathology and burden. Environ Health Prespect 88:295–303CrossRefGoogle Scholar
  29. Roggli VL, Pratt PC, Brody AR (1986) Asbestos content of lung tissue in asbestos associated diseases: a study of 110 cases. Br J Ind Med 43:18–28PubMedGoogle Scholar
  30. Sprent P (1993) Applied non-parametric statistical methods, 2nd edn. Chapman & Hall, LondonGoogle Scholar
  31. Timbrell V, Ashcroft T, Goldstein B, Heyworth F, Meurman LO, Rendall REG, Reynolds JA, Shilkin KB, Whitaker D (1988) Relationships between retained amphiboles fibres and fibrous in human lung tissue specimens. Ann Occup Hyg 32(Suppl 1):323–340Google Scholar
  32. Vorwald AJ, Durkan TM, Pratt PC (1951) Experimental studies of asbestosis. Arch Ind Hyg Occup Med 3(1):1–43Google Scholar
  33. Wagner JC, Pooley FD, Berry G, Seal RM, Munday DE, Morgan J, Clark NJ (1982) A pathological and mineralogical study of asbestos related death in the United Kingdom in 1977. Am Occup Hyg 26(1):423–431CrossRefGoogle Scholar
  34. Wagner JC, Moncrieff CB, Coles R, Griffiths DM, Munday DE (1986) Correlation between content of the lungs and disease in naval dockyard workers. Br J Ind Med 43:391–395PubMedGoogle Scholar
  35. Wagner JC, Newhouse ML, Corrin B, Seal RM, Munday DE, Morgan J, Clark NJ (1988) Correlation between content of the lung and disease in east London asbestos factory workers. Br J Ind Med 45:305–308PubMedGoogle Scholar
  36. Warnock ML, Kuwahara TJ, Wolery G (1983) The relation of asbestos burden to asbestosis and lung cancer. Pathol Ann 18(2):109–145Google Scholar
  37. Wright JL, Churg A (1984) Morphology of small airways lesions in patients with asbestos exposure. Hum Pathol 15:68–74PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Ataollah Nayebzadeh
    • 1
  • Bruce W. Case
    • 2
  • Janick Massé
    • 3
  • André Dufresne
    • 4
  1. 1.McGill University Health CentreMontréal General HospitalMontréalCanada
  2. 2.Department of PathologyMcGill UniversityMontrealCanada
  3. 3.Department of PathologyCité de la Santé LavalLavalCanada
  4. 4.Department of Epidemiology, Biostatistics, and Occupational HealthMcGill UniversityMontréalCanada

Personalised recommendations