State and Freeborn County health officials this week advised all homes in the state be tested for radon.

According to a Freeborn County Public Health news release, 66 percent of the homes in Freeborn County that were tested for radon in 2012 had levels higher than what is advised. The county is the 12th highest in the state for average radon concentration.

Radon exposure is the second leading cause of lung cancer among nonsmokers across the country, and more than 21,000 deaths are attributed to it each year, the release states.

The Department of Health estimates one in three homes in the state has radon levels that pose large health risks over many years of exposure.

Freeborn County Public Health Director Sue Yost said high radon levels can be found in both new and old homes.

Free radon testing kits are available at the Freeborn County Public Health Office in the Freeborn County Courthouse. Testing takes between three and five days.

In homes with levels over what is advised, homeowners should consider verification testing and possibly install a radon mitigation system.

The release states testing for radon is the only way people can find out if their homes have an elevated level of radon.

The radioactive gas is odorless, colorless and tasteless and can occur naturally in Minnesota soils. It can enter homes through cracks and openings in the basement or foundation floors and walls.