Radon is the number one cause of lung cancer among non-smokers, according to EPA estimates. Overall, radon is the second leading cause of lung cancer. Radon is responsible for about 21,000 lung cancer deaths every year. About 2,900 of these deaths occur among people who have never smoked.
See: Health risks of radon
- A Citizen's Guide to Radon (PDF) (16 pp, 730 K, May 2012, EPA 402/K-12/002)
- National Cancer Institute Fact Sheet on Radon & Cancer