January is National Radon Action Month, and Teton County Health Department is reminding you to test your residence, office, or rental for radon. Short-term radon test kits are available for $10 at the Teton County Health Department. Radon is a radioactive gas that naturally occurs from the breakdown of uranium in rocks, soil, and groundwater. Radon gas enters homes and buildings from the soil beneath and can build up to high levels indoors. When people breathe radon, the radioactive decay products damage lung tissue, which can increase the likelihood of developing lung cancer. The Surgeon General of the United States has warned that radon is the second leading cause of lung cancer in the country today.