The retention and clearance of inhaled glass fibre and different varieties of asbestos by the lung

Abstract

The inhalation of fibrous dusts draws many millions of fibres into the lung where they may cause damage and disease. Some fibres enter the lung more easily than others and some are more readily removed than others. In this study the lungs of baboons which had been exposed to different types of fibre were examined and the build up of fibres in the lung after different periods of exposure plotted. Similarly the clearance of fibres from the lung after exposure was determined. Significant differences between glass fibres and asbestos fibres were found. The clearance of the fibres was expressed in terms of a 'half life'. The half lives varied from 6 months for glass fibre to 50 months for crocidolite asbestos. This is a possible factor in the development of lung disease following extended exposure to fibrous dust.