Radon exposure is fueling Iowa’s deadliest cancer

This story first appeared in the Sept. 2 edition of the Iowa Starting Line newsletter. Subscribe to our newsletter to get an exclusive first look at a new story each Tuesday in our The Hot Spot: Investigating Cancer in Iowa series.

Iowa has the highest radon levels in the nation, and doctors say the gas is causing hundreds of lung cancer deaths every year.

Rosemary Geiken didn’t know what radon was, let alone the dangers of it, when she was raising her children in Tripoli, Kesley, and Dumont in Northeast Iowa. So she never thought to test for it, either.

“Growing up, no, we never tested,” Geiken, who now lives in Urbandale, said. “It wasn’t a thing.”

The same thing happened to AnMarie Rodgers, a native of Newton who was surprised to be diagnosed with lung cancer in 2024.

Neither Rodgers nor Geiken’s daughter, Sara, had a history of smoking. Both were told by doctors that radon—an invisible gas caused by the decomposition of radium-226, found in high concentration in the soil across Iowa—was the likely cause behind their lung cancer.

“I don’t think it was that widely known,” Rodgers, now living in Oakland, California, said.

Sara Geiken died in 2024 at the age of 44—one of 400 Iowans estimated to die every year from radon-induced lung cancer. Yet the dangers of radon are only just becoming known.

“[Doctors] said, ‘Have you lived somewhere where it’s high in radon?'” Geiken said. “We hadn’t even heard of radon.”

The hidden carcinogen

Radon gas comes from radium-226, produced by the decay of uranium, a naturally occurring element in the environment. Glaciers that once covered Iowa left behind finely ground rocks containing the element—so much so that the state now has the highest average radon concentration in the United States.

And it’s everywhere: When the Environmental Protection Agency first mapped radon in 1993, it found high levels in all of Iowa’s 99 counties.

It’s only been in the last 20 years, however, that scientists have connected lung cancer to elevated radon levels in homes.

Lung cancer is the third-most common cancer diagnosis in Iowa. Yet it’s by far the deadliest, accounting for around 22% of all Iowa cancer deaths.

Radon is now estimated to be the second-leading cause of lung cancer nationally, behind smoking tobacco. An estimated 12% of all lung cancer diagnoses are caused by radon. It is also the leading cause of environmental lung cancer death in Iowa.

The risks

When AnMarie Rodgers was a child, she developed asthma and allergies so badly that her parents moved the family to a new house in Newton when she was in ninth grade. Her father, an engineer who died in 2001, made sure the home’s indoor air would help alleviate his daughter’s respiratory ailments.

“So from then on we had a really good air purifier system in the house,” Rodgers said. “But it also meant that it was really well sealed up.”

A test she did in her childhood home after her 2024 diagnosis revealed radon gas—which her father never thought to test for—built up in that sealed home. Rodgers believes it caused her lung cancer.

“I think if he’d have known it was a risk … I think he would’ve been able to fix it himself,” Rodgers said. “It just wasn’t done.”

Losing his own father to lung cancer in 2009 drives Kyle Hoylman in his work as CEO at Protect Environmental, the largest radon contractor in the nation.

When he tested his childhood home in Kentucky, where his dad lived, Hoylman found it contained 30 picocuries of radon per liter (pCi/L)—far over the EPA’s threshold of 4 pCi/L. (The EPA notes there is “no safe level of radon.”)

“These things start to come off of the soil through pathways into the home,” Hoylman said, like gaps and cracks in your basement or construction materials. “You and I are breathing it, [and the] radon particle gets trapped in our lung.”

And he knows Iowa’s at an even higher risk.

“You are at the epicenter of radon for the United States—60% of your buildings tested have radon concentrations above the EPA action level,” Hoylman said. “To put that into perspective, at 4 picocuries, that’s a radiation dose equivalent of 200 annual chest x-rays, or half a pack of cigarettes a day.”

What can be done

You can’t tell the story of radon in Iowa without Gail Orcutt.

Just two years after she retired as an Iowa school teacher, Orcutt was diagnosed in 2010 with radon-caused lung cancer. The Altoona woman immediately threw herself into teaching others about radon’s dangers until her death in 2020.

Not long after her death, Iowa passed the Gail Orcutt School Radon Safety Bill, which requires radon testing (and mitigation if necessary) in all public schools at least once every five years. Iowa also requires child care centers to test for radon every two years, and mitigate if levels above 4 pCi/L are found.

Yet we have no requirements for testing or mitigation in homes, something Hoylman recommends.

“In Iowa, you take these new homes—12,000 of them last year—60% of those have a radon problem,” he said. “The industry doesn’t fix 7,000 homes every year in Iowa. We’re going backwards, not forwards, in reducing the occupant risk to radon.”

That could change soon.

Several cities and counties, and the Meskwaki Tribe, now require Radon Resistant New Construction (RRNC), a method of preventing radon gas while building instead of after. It’s something Hoylman said can start to solve the problem.

“We have to draw a line in the sand and say, from this point forward, any new home, any new building, school, whatever it is, must have a passive soil gas control system installed,” he said.

State Rep. Hans Wilz, a Republican from Ottumwa, introduced a bill this spring that would require home builders across Iowa to install such systems in new homes. It would also set up state tax credits of up to $1,000 for Iowans to install mitigation systems in existing homes and buildings.

“Seven out of 10 homes in Iowa have radon levels that pose a health risk,” Wilz told Radio Iowa, noting mitigation would save hundreds of millions of dollars in health care costs.

The bill passed the Iowa House, but didn’t get a vote in the Senate, though no lobbyists registered against it. The Legislative Services Agency estimates the bill would have cost the state around $3 million in the first year.

Wilz told Iowa Starting Line he did plan to bring this bill “and/or a similar bill” back to the Iowa House in 2026.

Anyone can purchase a short-term or long-term radon test kit from local hardware or big-box stores; they can run from $15 up to $120 or more for continuous radon monitoring.

Rosemary Geiken tested her own apartment in Urbandale after her daughter’s death, and found her reading was at 18 pCi/L—more than four times the EPA’s limit.

She said her building manager and owners “did a fantastic job” of immediately correcting the problem. But Geiken had to educate the manager at first, too: “She had no clue what radon even was.”