Asbestos Body Formation in the Human Lung: Distinctions, by Type and Size

Abstract The fraction of fibers coated in a total of 3 800 asbestos fibers from 38 patients with disease related to asbestos (100 fibers per patient) was determined, according to asbestos fiber type and size parameters. Among the 3 800 fibers, 638 (16.8%) were coated and 3 162 were uncoated. All fibers were analyzed at 2 000x magnification (lower limit of detection: 2 μm for length and 0.06 μm for diameter). The diameter of the totally coated fibers (28.4% of total bodies; 181/638) was not measured. The percentage of coated fibers varied with the asbestos type; it was 27.1% (335/1235) for amosite fibers, 16.0% (228/1423) for crocidolite, 6.6% (60/908) for tremolite or actinolite, 6.5% (14/214) for anthophyllite, and 5% (1/20) for chrysotile fibers. Most coated fibers were longer than 10 μm and had an aspect ratio (length/diameter) of more than 20. Approximately 60% of coated fibers had an aspect ratio of more than 100. The longer the fiber, the greater the percentage of coated fibers, regardless of diamet...