Story updated 2:02 p.m. Friday, Feb. 5.
There is an odorless, colorless and tasteless risk lurking in around 40 percent of Minnesota homes, responsible for over 21,000 lung cancer deaths each year.
Radon is the leading cause of lung cancer in nonsmokers, even above second-hand smoke, and there are more deaths caused by radon than drunk driving deaths per year, according to the Environmental Protection Agency.
The radioactive gas is a subtle health hazard, existing naturally in the ground and air. The gas seeps into homes through cracks, pores or exposed soil, and once inside, it becomes trapped, breaking down further.
Richard Lively, geologic information scientist with the University of Minnesota, Minneapolis, has dedicated years to studying the gas.
“Health departments keep trying to point out that this is a big problem, that this is a large cause of lung cancers and deaths, but it doesn't really resonate with people,” Lively said.
Part of the public apathy toward radon is because it’s natural and intangible. If it does cause lung cancer later in life, people aren’t likely to attribute their disease to radon exposure in the way they would attribute it to a habit like smoking, he said.
A daughter product of uranium, the gas forms in rock and soil as uranium decays. Small bits of uranium are present in every rock, but some types of rock, like granites, metamorphic and sedimentary rocks, contain higher levels of the element.
Radon was thrust into the public’s eye in the 1980s when a Pennsylvania man who worked at a nuclear power plant set off the radiation alarms each time he entered his work site.
“The Reading Prong,” Lively said. He knows the story well. The Pennsylvania man lived in a geological region of New England known as the Reading Prong that has abnormally high levels of uranium in the rocks. His home, along with many others, was built directly on top of the area.
Radon has been found in every state, however, a map of the U.S. reflects higher levels of radon in the northern parts of the country, including Minnesota and North Dakota. This is partially due to glacial sediment in the region, Lively said.
Lawrence Livermore National Laboratory conducted a study on radon in the Red River Valley and found the levels to be high due to clay soils, Lively said.
Radon does not discriminate by the age, architecture or sturdiness of a home. It can exist in brand new homes, old homes, drafty homes, insulated homes and homes with and without basements, according to the EPA.
The only way to know a home’s radon levels is to test it, the Minnesota Department of Health stated.
“Radon testing and mitigation increased from 2010-2015, and it has held steady in the last five years,” said Dan Tranter, supervisor of the Indoor Air Program at MDH. “Unfortunately, many people are still being exposed to high levels of radioactive radon who don’t know it. With more people working and schooling from home, it’s especially important now to test your home.”
Nationally, the average radon level is 1.3 pCi/L. No level of radon exposure is considered safe, but the World Health Organization sets the recommended radon level for homes at 2.7 pCi/L.
Dosing is still largely misunderstood, Lively said. As a gas, radon gets breathed in and out all the time. The danger comes from the byproducts of radon as it begins to break down into small particles like lead and plutonium. Those particles are what attach to the lungs or other things in the atmosphere like dust, he said. Keeping a dusty home may actually be protecting him from radon, Lively joked.
The particles cannot be detected and dosed, which is why the benchmark surrounds radon gas levels.
“The reality is, it’s very complex, which is another reason nobody can really come up with a good dose estimate because there’s a lot of complications going on,” Lively said.
The average radon level in Minnesota homes is 4.5 pCi/L. Two out of every five Minnesotan homes tested have radon levels that are a major health risk, according to MDH.
There are an average of 13 homes tested per year in Wilkin County, Minnesota. Out of the homes tested in the county, 44.8 percent had radon levels equal to or above 4 pCi/L.
There are short-term (two to seven days) and long-term (up to one year) radon tests. Radon test kits range from $5-40 depending on the brand and type.
Maggie Wiertzema of Wilkin County Public Health said testing has slowed in the county due to COVID-19. The county offers testing kits for around $10, but Wiertzema said if an individual is unable to pay, they can receive the test for free.
“You want to put (the test) in the lowest level of living space. So if you’re not in your basement very often, you wouldn’t want to put it there, but if you have bedrooms in your basement, you should test there,” Wiertzema said.
If a home test reflects hazardous levels of radon, residents should seek a radon mitigation professional. Radon mitigation may involve installing pipes near the radon’s entry source and pulling the air outside.
“Fortunately, the risk is largely preventable through testing homes and fixing radon problems,” MDH stated.