Asbestos fibers are microscopic and therefore easily inhaled or swallowed. Once inhaled, they get lodged in the pulmonary tissues (as shown in this image) and peritoneal lining. Asbestos exposure has been linked to a number of lung and respiratory conditions including, asbestosis, lung cancer, and mesothelioma. About 2000 to 3000 mesothelioma cases are diagnosed yearly in the US. Peritoneal mesothelioma makes up about 20% of these cases.