Radon is a cancer-causing radioactive gas. You cannot see, smell, or taste radon but it may be a problem in your home. When you breathe air-containing radon, you increase your risk of getting lung cancer. Testing is the only way to know your home’s radon levels. There are no immediate symptoms that will alert you to the presence of radon. The Board of Health does not test for radon. Learn more with the Environmental Protection Agency.