The Wisconsin Department of Health Services (DHS) is encouraging Wisconsinites to check their homes and businesses for radon, the second leading cause of lung cancer nationally. Of the estimated 21,000 lung cancer deaths each year from radon, around 962 are in Wisconsin, according to the DHS. They said radon is an odorless, radioactive gas that’s naturally present in the ground and seeps through the foundations of buildings. A state health officer, said one in 10 homes in the state have elevated radon levels.