What does fiber size have to do with asbestos-related lung disease?
Depending on their shape and size, asbestos fibers deposit in different areas of the lung. Fibers less than 3 mm easily move into the lung tissue and the lining surrounding the lung (pleura). Long fibers, greater than 5 mm (1/5 inch), cannot be completely broken down by scavenger cells (macrophages) and remain in the lung tissue. These asbestos fibers can cause inflammation. Substances damaging to the lungs are then released by the cells of inflammation that are responding to the foreign asbestos material. The persistence of these long fibers in the lung tissue and the resulting inflammation seem to initiate the process of cancer formation. As inflammation and damage to tissue around the asbestos fibers continues, the resulting scarring can extend from the small airways to the larger airways and the tiny air sacs (alveoli) at the end of the airways. Some of these fibers can move to the surface of the lung where they form plaques (white-gray regions of scarred tissue) in the tissue lini
