Lung cancer is the leading cause of cancer deaths in the United States, according to the National Institutes of Health. Most people who get lung cancer are over the age of 65. While some risk factors such as family history are beyond an individual's control, certain steps can decrease, or eliminate, the most common and well-established risks associated with this form of the disease.
Smoking
Cigarette smoking is by far the most common cause of lung cancer. An estimated 85 percent of lung cancers are directly attributed to this behavior, Merck Manuals Medical Library cites. The more a person smokes, the greater the risk of lung cancer. Secondhand smoke also poses a danger. Secondhand smoke, or passive smoke, is smoke streaming directly from burning tobacco, or smoke exhaled from someone who is smoking. According to the American Cancer Association, secondhand smoke is classified as a carcinogen and may account for up to 3,400 lung cancer deaths each year in non-smoking adults.
Asbestos
Asbestos is a mineral once commonly used in materials such as insulation, fireproof materials, drywall and in shipbuilding. Its tiny fibers can travel through the air and embed in the lungs, increasing one's chances of developing cancer. Low levels of asbestos are found around people constantly, but most people will not become ill from this exposure. Those most commonly affected are generally those who work with it regularly. Safety measures enacted in the 1970s have strictly curtailed the use of asbestos so that exposure has dropped dramatically. Still, according to the National Institutes of Health, millions of Americans have been exposed to the carcinogen since the 1940s.
Radon
Radon is a naturally occurring gas from decaying uranium. As it breaks down, it emits radioactive particles that can damage the lungs and promote the growth of cancer. It comes from rock and soil under and around foundations and can build to dangerous levels in homes and other buildings. Radon is associated with about 21,000 deaths each year, and 2,900 of these deaths occur in people who have never smoked.
Occupation
Work-related exposures, especially in the chemical and construction fields, raise the risk for lung cancer. Tar, soot, nickel, arsenic, chromates and mustard gas are some of the substances that can be breathed in, elevating the risk of lung cancer.
Family History
Those with a parent or sibling who have had lung cancer are at slightly increased risk for developing the disease, even if a person has never smoked. According to Merck Manuals, 15 percent of those with lung cancer have never smoked.
Tuberculosis
Tuberculosis and other diseases that cause significant scarring of the lungs are associated with an increased risk of developing lung cancer.
