Asbestos fiber content of the lungs in patients with and without asbestos airways disease.

Abstract

I analyzed the total pulmonary asbestos burden in the lungs of 9 chrysotile miners who had asbestos airways disease (so-called "early asbestosis") but no evidence of classic asbestosis (interstitial fibrosis) on pathologic examination. The results were compared with values found for 9 miners matched for age, sex, smoking, and work length who had no histologic evidence of asbestosis or asbestos airways disease. The mean value for chrysotile fibers in the airway disease group was 47 X 10(6)/g dried lung, compared with 23 X 10(6) in the group without lesions (p less than 0.04). For contaminant amphiboles, probably derived from the chrysotile ore (tremolite, actinolite, anthophyllite), the corresponding values were 106 X 10(6) versus 58 X 10(6) (p less than 0.06), and for total asbestos fibers, 153 X 10(6) versus 81 X 10(6) (p less than 0.06). There was a strong correlation between amount of chrysotile and amphibole for each case, suggesting that the amphibole was probably a good measure of the original (but no longer present) chrysotile burden. No differences were seen between the 2 groups with regard to fiber size distribution, aspect ratios, or fiber widths. I conclude that the overall differences in fiber concentration between the 2 groups, although significant, are sufficiently small enough to suggest that other factors may be involved in the genesis of small airway lesions.