The inhalation of asbestos fibers can cause serious illnesses that are strongly associated with exposure to asbestos.  Airborne asbestos fibers are a significant health threat because asbestos fibers are microscopic and invisible to the human eye. In addition, they have the physical characteristics to bypass the ability of the human lung to filter air contaminants. As a result, exposure to asbestos allow the fibers to reach deep within the lungs, and may irritate and scar lung tissues. Long-term chronic and acute exposure to asbestos fibers may cause respiratory diseases such as lung cancer, asbestosis and mesothelioma.