Effects of talc dust on respiratory health: results of a longitudinal survey of 378 French and Austrian talc workers
- 1 INRS, Vandoeuvre, France
- 2 AUVA, Graz, Austria
- 3 Rio Tinto Minerals, Toulouse, France
- 4 Rio Tinto Minerals, Graz, Austria
- Pascal Wild, INRS, Département Epidemiologie en Entreprise, BP 27, 54501 Vandoeuvre cedex, France;
- Accepted 20 September 2007
- Published Online First 10 October 2007
Objectives: The aim of this longitudinal study was to investigate the effects on respiratory health of talc dust, free of asbestiform fibres, at or below airborne concentrations of 2 mg/m3.
Methods: The respiratory health and dust exposure of all workers with at least 5 years of employment at two talc producing facilities in France and Austria were surveyed between 1988 and 2003. Standard forced expiratory volumes and standard chest x rays were obtained on repeated occasions and recorded using strict quality control procedures. Of a target population of 430 subjects, 378 (88%) were examined at least twice. A quantitative exposure matrix was set up based on 4602 personal exposure measurements of respirable dust and qualitative descriptions of the industrial processes and individual protection devices.
Results: The mean duration of follow-up was 14.5 years with a mean estimated talc dust concentration during follow-up of 1.46 mg/m3. The prevalence of small radiological opacities and lung function parameters were significantly related to cumulative exposure at inclusion but not to exposure during the study period. Overall, the forced expiratory volume in 1 s decreased by 66 ml per 100 years.mg/m3, which is less than that reported for other types of mineral dusts.
Conclusions: Although early exposure levels to talc as assessed at inclusion were associated with decreased lung function and an increased prevalence of small radiological opacities, there was no evidence of detrimental effects of talc exposure, as assessed within the study period, on lung function and small radiological opacities.
Funding: The study was funded by INRS and AUVA. The Rio Tinto Minerals Company (formerly the Luzenac Group) provided funding for travel expenses, quality checking of the lung function measurements and quality checking of some of the x ray measurements and data input. Most of the data were generated as part of the occupational health assessment of employees. The company did not influence the design of the study, its analysis or discussion. Publication was guaranteed, whatever the results, as part of the study protocol officially approved by the company.
Competing interests: None