Radon Health Risks
Is Radon Dangerous? Iowa Radon Health Risks
Radon is invisible, but the health risk is well documented. Here is a calm, factual look at what radon is, why it harms the lungs, and why Iowa homes deserve special attention.
Yes. Radon is dangerous. It is the second leading cause of lung cancer in the United States after smoking, linked to about 21,000 deaths a year according to the EPA. It is invisible and odorless, so the only way to know your home is safe is to test. Iowa has among the highest radon levels in the country.
What Radon Actually Is
Radon is a naturally occurring radioactive gas. It forms when uranium, which is present in soil and rock across much of the planet, breaks down over time. As uranium decays, it produces radium, and radium decays into radon. Because radon is a gas, it moves up through soil and can seep into homes through foundation cracks, sump pits, crawl spaces, and gaps around pipes.
Outdoors, radon disperses into the open air and stays at low concentrations. The problem starts when it enters an enclosed building and accumulates. Modern, well-sealed homes can actually trap radon more effectively than drafty older ones, so a newer house is not automatically a safer house when it comes to radon.
Radon levels are measured in picocuries per liter of air, written as pCi/L. That single number is the basis for nearly every decision a homeowner makes about radon, from whether to act to how a system is designed.
Why Radon Harms the Lungs
The danger is not the radon gas itself so much as what it leaves behind. As radon decays, it produces tiny radioactive particles often called radon decay products, or radon progeny. When you breathe air that contains radon, some of these particles lodge in the lining of your lungs.
Once they are in the lungs, those particles continue to break down and release small bursts of radiation right against sensitive lung tissue. Over years of exposure, that radiation can damage the cells and the DNA inside them. Damaged cells can eventually develop into lung cancer. This is a slow, cumulative process, which is exactly why radon is easy to ignore. There is no cough, no irritation, and no warning at the moment of exposure.
The Headline Facts
- Radon is the second leading cause of lung cancer in the United States after smoking, according to the EPA.
- The EPA attributes about 21,000 lung cancer deaths in the United States to radon each year.
- Roughly 400 Iowans die from radon-related lung cancer each year, according to the American Cancer Society Cancer Action Network.
Smoking Raises the Stakes, but Nonsmokers Are at Risk Too
Radon and tobacco smoke each damage the lungs, and together the risk is considerably higher than either one alone. A person who smokes and lives in a home with elevated radon faces a much greater chance of developing lung cancer than a nonsmoker in the same home. If you smoke and your home has high radon, reducing both exposures matters.
That said, radon is a serious risk for people who have never smoked. Among nonsmokers, radon is a leading cause of lung cancer, and many of those cases are tied to long-term exposure inside the home. The takeaway is simple. Radon is a risk worth managing whether or not anyone in the household smokes.
You Cannot See, Smell, or Taste Radon
Radon gives no signal at all. It has no color, no odor, and no taste, and breathing it causes no immediate symptoms. A home with a dangerously high level feels exactly like a home with a low level. Two houses on the same street can have very different readings depending on their soil, their foundation, and how they were built.
Because there are no warning signs, testing is the only way to know your home's level. A short-term test kit can give you a first reading in a few days, and a longer test gives a more representative picture across seasons.
The EPA action level is 4.0 pCi/L. At or above that reading, the EPA recommends taking steps to reduce radon in the home. It is important to understand that there is no completely risk-free level. Lower is always better, and the EPA notes homeowners may consider acting even between 2.0 and 3.9 pCi/L.
Why Iowa Is Especially Affected
Iowa sits on glacial soils rich in uranium, which is part of why the state consistently records some of the highest indoor radon levels in the nation. The numbers tell the story clearly.
- The Iowa state average indoor radon level is around 8.5 pCi/L, compared with a US average near 1.3 pCi/L, according to Iowa HHS.
- Roughly 71.6% of Iowa homes that have been tested came back above the 4.0 pCi/L action level, per Iowa HHS.
- All 99 Iowa counties are designated EPA Radon Zone 1, the highest-potential category.
In short, an elevated result is common in Iowa, not the exception. That is a reason to test sooner rather than later, no matter where in the state you live.
The Good News: Radon Is Fixable
Radon is a manageable problem. The danger comes from long-term exposure, which means reducing your level meaningfully lowers your risk going forward. The path has two clear steps.
First, find out where you stand with a radon test. You can start with our radon action level calculator to understand what a given pCi/L reading means.
Second, if your level is elevated, the answer is radon mitigation. Properly installed systems typically reduce radon by 50 to 99% according to the EPA. A mitigation system vents radon from beneath the foundation to the outdoors before it can build up inside, and a well-designed system usually brings a home well below the action level.
We are a marketing service that connects Iowa homeowners with NRPP-certified, Iowa HHS-credentialed radon mitigation specialists. If your test result is elevated, you can request a free, no-obligation quote and an independent specialist will follow up.
Frequently Asked Questions
Is radon actually dangerous, or is the risk overstated?
The risk is real and well documented. The EPA identifies radon as the second leading cause of lung cancer in the United States after smoking, linked to about 21,000 deaths each year. The danger builds slowly over years of exposure, which is why it is easy to underestimate.
Can radon harm you if you do not smoke?
Yes. Smokers face the highest radon risk because smoking and radon damage the lungs in ways that compound each other, but nonsmokers are also at risk. Many radon-related lung cancer cases in nonsmokers trace back to long-term exposure at home.
How would I know if my home has dangerous radon levels?
You cannot. Radon has no color, no smell, and no taste, and it causes no immediate symptoms. Testing is the only way to know your level. The EPA action level is 4.0 pCi/L, and there is no completely risk-free level.
Why is radon such a big concern in Iowa?
Iowa has some of the highest indoor radon levels in the country. The state average is around 8.5 pCi/L compared with a US average near 1.3 pCi/L per Iowa HHS, roughly 71.6% of Iowa homes test above the action level, and all 99 counties are designated EPA Radon Zone 1.
If my level is high, can the danger be reduced?
Yes. Properly installed systems typically reduce radon by 50 to 99% according to the EPA. The path is to test first, then connect with an NRPP-certified, Iowa HHS-credentialed specialist for a mitigation quote if your level is elevated.
Worried About Radon in Your Home?
The only way to know is to test. If your level is elevated, connect with an NRPP-certified, Iowa HHS-credentialed specialist for a free, no-obligation quote.