The U.S. Environmental Protection Agency (EPA) reports that an estimated 1 in 15 homes in the country have high radon levels. The agency also warns that high radon levels can be a risk across the entire nation and that radon is the leading cause of lung cancer deaths among nonsmokers, claiming the lives of about 21,000 Americans each year., , , , Radon is a naturally occurring radioactive gas that is released in rock, soil, and water. In homes and buildings, it can accumulate to dangerous leve...