Despite state and federal recommendations, state officials say only 53 of 331 school districts in Minnesota reported that they have tested classrooms for radon since 2012.

Mankato Area Public Schools Facilities Director Scott Hogen told the school board that the district tests regularly for the naturally occurring, radioactive, cancer-causing gas. “Every five years we do radon testing, and every five years we do lead and water testing,” he said, and added, “We have not deviated from that plan.”

He explained that, “We divide the district into fifths; so, one fifth of our buildings are done, for instance, this school year. One fifth next year, the following year…. So, every year we are testing but we’re testing different facilities and every facility will fall into the five-year span.”

In Minnesota, 80 percent of counties are rated as radon “hot zones.” In Blue Earth County, more than 82 percent of homes tested in 2016 had elevated radon levels, and in over 60 percent the levels were high enough to be considered dangerous.

Hogen said they haven’t measured any levels that were cause for concern but, “We’ve had some elevated levels, slightly, but not that they are a hazard and we’ve been able to just make some adjustments in our ventilation systems to bring in more fresh air, flush it out of the building.”

The American Lung Association in Minnesota said that, after tobacco use, exposure to radon is the second leading cause of lung cancer.