More than 40 percent of Minnesota homes have levels of radioactive radon gas that could increase chances of lung cancer, according to an estimate by the state Health Department. Indoor Air Unit Supervisor Daniel Tranter says, “As a broad generalization, the southern third and the western third have higher radon levels. It has to do with the geology of the soil. It kind of lines up with the agricultural region of our state.”

Tranter says for example an estimated 80 percent of homes in Rock County have radon levels above the health threshold — but even in counties like Isanti and Anoka with the lowest numbers, 16 percent of homes are still estimated to have high radon levels.

Radon the number one cause of lung cancer for non-smokers and the second leading cause of lung cancer in smokers. Your risk for lung cancer increases with higher levels of radon and longer periods of exposure. If you smoke, the combined risk of smoking and radon exposure is much higher.

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