Asbestos
Asbestos is a naturally occurring mineral that was frequently used in commercial construction throughout the 1950's and 1960's. The long, thin fibers of asbestos are fragile and have a tendancy to break down into dust particles. Asbestos particles are easily inhaled into the lungs, where they cause damage to lung tissue that can lead to lung cancer.
Individuals who are exposed to asbestos and tobacco smoke are at a significantly increased risk of lung cancer. Studies suggest that asbestos particles may help deliver concentrated tobacco carcinogens to cells lining the lungs.(8)However the exact mechanism by which asbestos, alone or in combination with tobacco smoke, leads to lung cancer is still uncertain.