Because individual asbestos fibers are so tiny that they can only be seen with a microscope, they are very lightweight and stay in the air for a long time. Friable asbestos is especially dangerous. The term friable means that the asbestos crumbles easily, releasing asbestos fibers into the breathable air. An example of friable asbestos is acoustical ceiling and wall spray. Once inhaled, the asbestos fibers can cause many respiratory problems, including the development of mesothelioma.
Asbestos fibers are very strong - too strong for the human body to break down.
Asbestos fibers can also be swallowed, lodging themselves in the digestive tract. This may also lead to disease. Usually it takes at least 15 years from the time a person is exposed to asbestos until they develop mesothelioma. This is called the latent period.