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Radon is a health hazard in 40% of Minnesota homes, but few test for it, say health officials

MinnPost photo by Corey Anderson
The average level of radon in Minnesota’s tested homes is 4.6 pCi/L — more than three times the national average of 1.3 pCi/L.

Not enough Minnesotans are testing their homes for radon, despite the state having some of the highest average levels of the dangerous gas in the country, the Minnesota Department of Health (MDH) warned last week.

According to an MDH analysis of data collected during a recent five-year period, only 1 percent of properties in Minnesota have been tested for radon.  Yet that same data suggests that 2 in 5 (or about 40 percent) of homes in the state have a radon level of 4.0 picocuries per liter of air (pCi/L) or higher. 

MDH officials strongly recommend that buildings with verified radon levels of 4.0 pCi/L or higher have a radon mitigation system installed. 

The average level of radon in Minnesota’s tested homes is 4.6 pCi/L — more than three times the national average of 1.3 pCi/L.

“That has a lot to do with geology in the soil,” said Dan Tranter, supervisor of the Indoor Air Program for MDH, in an interview with MinnPost. “It also has to do with the fact that our houses are closed up much of the year.”

An ‘invisible’ danger

Radon is an odorless, colorless, radioactive gas that is created when uranium breaks down in the soil. The gas then seeps up from the ground, including through pores, cracks or other tiny spaces in a building’s floors or foundation. The gas can accumulate in buildings — and eventually be inhaled by the buildings’ occupants.

Radon is the leading cause of lung cancer among nonsmokers in the United States, and is linked to 21,000 deaths each year, according to the Centers for Disease Control and Prevention. About 600 of those annual radon-related deaths occur here in Minnesota, said Tranter.

“It’s very important to test your home for radon because it’s one of the most significant health problems in homes,” he said.

Winter is a particularly good time to do radon testing because, with windows closed, levels of the gas are likely to be concentrated, giving an accurate assessment of the year-round risk. Radon test kits are inexpensive, easy to use and produce results within three to seven days. Hardware stores carry them (starting at around $10), but Minnesotans can also get a test kit from participating city or county health departments at low or no cost.

Not many options

What is not available free of cost, however, is the mitigation system for reducing radon levels in a home, which usually involves installing a pipe under the house, with a continuously running fan that pulls the radon from the ground and vents it outside.

“Some people cannot afford the $1,500 to $2,000 to fix their house,” said Tranter, “and there aren’t grants out there to help them pay for that.”  

Nor do renters currently have any options — other than to move when their lease is up — if a radon test detects high levels of the gas in their rental house or apartment and their landlord declines to fix the health hazard, said Tranter.

Homebuyers, however, do have some protections. New building code requirements enacted in 2009 has led to fewer radon gas problems in newly constructed homes, said Tranter. And the 2014 Minnesota Radon Awareness Act requires home sellers to tell potential buyers whether their home has been tested for radon gas and, if so, what has been done to fix the problem.

These changes — along with an improved economy and greater awareness about the dangers of radon — may be why there has been a threefold increase in the number of homes tested for radon since 2010, as reported by the MDH. 

Still, with only 1 percent of homes in the state tested — and 40 percent of homes containing potentially dangerous levels of the gas — we still have a long way to go.

FMI: MDH has a host of useful radon-related information on its website, including an interactive map that shows county-by-county radon levels (based on tested homes) and a list of state-certified radon contractors/mitigators. The website also includes important information about when and how to test your house — and how to interpret the results.

Comments (2)

  1. Submitted by Victoria Wilson on 01/05/2017 - 10:15 am.

    radon and houses

    Disclaimer: health issues are terribly important and, to appear insensitive or cavalier about something as horrible as lung cancer is beyond reprimand. So it is with hesitation that one confronts claims of health improving activities.
    However a tie between real estate and lung cancer would seem to imply that if: ‘The average level of radon in Minnesota’s tested homes is 4.6 pCi/L — more than three times the national average of 1.3 pCi/L.’ , Minnesotans should have higher rates of lung cancer. This site claims that rates of lung cancer deaths among MN men and women place us 39th among states.
    Taking the statistic of 600 out of 21000 radon related deaths does not appear to correlate with the claim that we dwell in high risk homes, homes that are said to have three times the exposure to radon, homes that we are confined in for much of the year due to our extreme weather.
    It just seems like there is more research to be done to understand the origination of radon related lung cancer deaths. If we are spending ($1800/home)tracking down the wrong remedy, aren’t we equally liable to our public health?

  2. Submitted by Keith Pickering on 01/05/2017 - 03:48 pm.

    Is household radon dangerous?

    Well I see it’s CDC’s annual Scare-everybody-with-radon Week again. While very large amounts of radon (as used to be seen in uranium miners in the 50s and 60s) can cause lung cancer, epidemiological evidence that radon at the low levels found in homes — even in the most radon-intense areas of the country — causes lung cancer is precisely zero. In fact, the most recent large scale study (Simeonov & Himmelstein 2015) found that the second-leading cause of lung cancer isn’t radon, it’s oxygen: living at low altitude. Radon was a weakly significant *protection* against lung cancer — even after correcting for smoking, elevation, race, education, and overall cancer rate in 2600 US counties.
    But some people’s jobs depend on doing useless & expensive radon mitigation, so I guess mere truth must take a back seat.

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