Radon gas is a risk factor for developing lung cancer. However, smoking is the greatest risk factor for lung cancer. The risk of lung cancer is increased for people who smoke, are exposed to secondhand smoke, and also have radon contact. The risk of radon-related lung cancer is 12 times higher for smokers than nonsmokers.¹

Everyone has some contact to radon. Radon is a gas that is released from rock and soil and is present in the air. In closed spaces, such as caves, mines, and energy-efficient homes, radon levels can increase because the gas cannot freely exchange with outdoor air.

Radon levels can be measured in enclosed spaces. Better ventilation can lower radon levels. Local, state, and federal environmental offices have information on radon.