MINNEAPOLIS (WCCO) — You can’t see, smell or taste radon in your home. But that doesn’t mean it isn’t there, according to Dr. Jon Cole of the Minnesota Poison Control System.

“You have no symptoms while it’s happening, and then later on, eventually you … develop lung cancer,” Cole said.

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Radon is the leading environmental cause of lung cancer deaths in the U.S., which kills 21,000 people each year. The Minnesota Department of Health says 40 percent of homes in Minnesota have elevated levels of the gas.

Dan Tranter is with the Indoor Air Unit of the Minnesota Department of Health.

“Any home can have a radon problem,” Tranter said. “That radon gas moves around in the soil and comes up underneath the foundation of our homes and then it gets sucked into our homes.”

With January being National Radon Action Month, the city of Minneapolis is giving out free radon test kits to the first 200 people who apply.

“You can place this on a shelf or you can hang it from a light fixture, and after three to seven days you take it down, take the sponge out, toss that, seal it up, fill out the information,” Tranter said.

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You put the self-addressed kit in the mail to be sent to a lab where they’ll test your radon level for you. If a test comes back with high radon levels, it can be fixed.

Health officials say you should test a home for radon levels before you buy, and test every two years after that.

The only symptoms of radon poisoning come years after exposure. Testing for radon is the best preventative medicine.

“The symptoms would be symptoms of developing lung cancer,” Cole said. “This is where prevention is everything.”

The free radon test kits are available at the City of Minneapolis Development Review. You can also check with your county to find test kits.

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Kate Raddatz