• mesothelioma
• asbestos induced lung disease
• lung cancer
• occupational lung disease

The paper by Thomsen et al 1 is a significant contribution to the now-substantial body of literature on the relationship between asbestos-related diseases and vehicle repair work. It is a large study, inclusive of all registered vehicle mechanics in the country for the designated years, with a mean follow-up time of 20 years and a maximum of 45 years. Several comprehensive administrative databases were linked for exposure and disease outcomes. The numbers of outcomes for the three main diseases of interest produced relatively narrow CIs.

The authors present data indicating that reliance on administrative databases for health outcomes was unlikely to be a problem for mesothelioma and lung cancer; however, it is reasonable to question the validity of the diagnoses of asbestosis based on administrative data alone. As the authors point out, the statistically significant elevation in asbestosis mortality and morbidity is somewhat puzzling given the relatively high exposures required for asbestosis and the relatively low asbestos exposures experienced by vehicle mechanics. The existing literature does not support a positive relationship between asbestosis and vehicle repair work.2–5 The authors suggested that diagnostic bias may have played a role, but this is speculative.

The result warrants further examination, possibly a nested case–control study with documentation of the diagnostic criteria supporting the database entries, blinded re-evaluation of the available diagnostic material, and further exploration of complete occupational histories.

The investigators observed a slight elevation in lung cancer risk. The results are consistent with those from an earlier meta-analysis6 and are unremarkable.

Studies of potential asbestos-related diseases among vehicle mechanics have focused primarily on risk of …