The South Carolina Department of Health and Environmental Control has produced a map showing that radon levels in upstate South Carolina homes are higher than other parts of the state.  Nicole Martinez  is an expert in radiological health sciences, and Lindsey Shuller-Nichols is a material scientist — both in Clemson's Department of Environmental Engineering and Earth Sciences. They're going to help us understand what causes radon, why it's higher in the upstate, its potential health effects and resources for testing and mitigation.