According to CBS Atlanta, lung cancer kills thousands of Americans each year. Smoking, radon and secondhand smoke have all been linked to the development of lung cancer. While treatable, the survival rates of lung cancer are one of the lowest. Between 11 and 15 percent of those diagnosed will live beyond five years. However, in many cases lung cancer is preventable.

The EPA estimates that 20,000 lung cancer deaths each year are radon-related. Radon is a form of ionizing radiation and is a proven carcinogen. Approximately 85% of radon-induced lung cancer patients die within 4-5 years of diagnosis.

Two studies have shown definite evidence of association between residential radon exposure and lung cancer. One study in North America combined data from several previous residential studies. Both studies confirmed the radon health risks predicted by occupational studies of underground miners who breathed radon for several years. Some researchers had questioned earlier whether occupational studies could be used to calculate risks from exposure to exposure to radon in the home environment.

The EPA’s former director of Indoor Environment Division said that the studies’ findings effectively end doubt about the risks of having radon in the home. Breathing even low levels of radon could lead to lung cancer, said Tom Kelly.

Dr. Michael Repacholi, coordinator of WHO’s Radiation and Environmental Health Unit said that radon poses a health risk to populations all over the world, but that the risk can be reduced. While radon health risks have received widespread attention, the carcinogen is the main source of exposure to ionizing radiation, and accounts to 50% of the public’s exposure to naturally-occurring sources of radiation, said Repacholi.