Quantification and particle size distribution of inhaled fibres in the lung

The number and size distribution of fibres in the lungs of 11 asbestos-exposed and 10 nonexposed individuals were determined. For fibre isolation, low-temperature incineration of lung tissue was used. The mean numbers of fibres per gram of dry lung, based on light microscopy, were 141.9 X 10(6) and 1.5 X 10(6) in the asbestos-exposed and nonexposed lungs, respectively. The fibre length found most frequently ranged between 3-5 micrometers in both groups. Asbestos, either chrysotile or amphibole, was found only in the group occupationally exposed to asbestos. No correlation between number of fibres and lung pathology could be established.