Maybe you've heard of people who don't smoke but have lung cancer. Can this happen? In fact, besides smoking there are a number of other factors that can increase a person's risk of lung cancer. Smoking is the most common cause of lung cancer. But not all cases of lung cancer occur in active smokers. To avoid this disease, you should know the cause of lung cancer in people who don't smoke. Various Causes of Lung Cancer in People Who Don't Smoke Here are some things that can be causes and risk factors for people who don't smoke but get lung cancer: 1. Exposed to radon gas exposure Radon gas exposure is known to be a cause of lung cancer in nonsmokers. Radon gas is naturally present in the air and is generally harmless. Even so, the level or concentration of radon gas can increase in homes built on land containing natural uranium deposits. In one study, it was found that the risk of developing lung cancer was higher in people who lived for years in radon-...