A homebuyer's concern is RADON, which is an odorless, colorless, radioactive gas that can be found in some homes. RADON is a naturally occurring gas that is produced by the breakdown of uranium in soil, rock, and water. It can enter a home through cracks in the foundation or other openings, and it can accumulate to dangerous levels if not properly ventilated. RADON exposure has been linked to an increased risk of lung cancer, so it is important for homebuyers to have their homes tested for RADON before purchasing.