February is National Cancer Prevention Month and more than half of Iowa homes are contaminated by a gas which can lead to lung cancer. Radon is a colorless, odorless, tasteless gas, that causes no immediate health issues but prolonged exposure can lead to lung cancer. Jennine Wolf, Director of Washington County Environmental Health says, more than half of homes in Iowa have elevated radon levels. This is believed to be the highest levels in the country. She says it is important to have your home tested. Wolf says you can buy a test for $8 to see if your home has high radon levels. If your house does test positive for elevated levels, contractors can retrofit your home with a system to ventilate the gas outside where it is harmless.