Beyond the lungs: New research links radon exposure to brain and ovarian cancer

Two new studies link radon exposure to brain and ovarian cancer, and Utah homes have more of it than most.

For decades, the warning about radon has been simple and specific: it causes lung cancer. The EPA calls it the second leading cause of lung cancer in the United States, behind only smoking. But two major studies published in 2026 suggest this invisible, odorless gas may pose health risks well beyond the lungs.

Utah residents can request a free radon test kit at utahradon.org/cancer-research.

Here is what the latest research found.

The brain cancer finding

A September 2026 study in the journal Neuroepidemiology, drawing on data from more than 159,000 women followed for nearly 18 years, found a significant association between residential radon levels and malignant brain and central nervous system cancers.

Women living in homes with the highest radon concentrations had a 49% higher risk of CNS cancer compared to those in the lowest radon homes (hazard ratio 1.49, 95% CI 1.12 to 1.99).

The researchers, from Oregon State University, UNC Chapel Hill, Harvard, and other institutions, estimated that radon exposure may account for roughly 20% of CNS cancer cases in the population they studied, cases currently attributed to unknown causes.

"These findings add to growing evidence suggesting that radon may exert carcinogenic effects beyond lung cancer, particularly in non-occupational, general populations," the authors wrote. Notably, the study observed elevated risk even at radon concentrations below the EPA's current action level of 4.0 pCi/L.

The ovarian cancer finding

Six months earlier, in April 2026, a JAMA Network Open study followed more than 127,000 postmenopausal women for 31 years.

It found that women living in homes with high radon had a 31% higher risk of ovarian cancer, and a 38% higher risk of serous ovarian cancer specifically, which is the most lethal subtype. Ovarian cancer mortality was also significantly elevated in homes with high radon.

Together, the two studies make something clear that lung cancer researchers have suspected for years: Radon's radioactive decay products don't just damage lung tissue. They enter the bloodstream, reach other organs, and may contribute to a far wider range of cancers than public health guidance has acknowledged.

Why Utah homes matter here

Utah sits atop uranium-rich geology. According to data from Alpha Energy Laboratories, which has analyzed more than 115,000 Utah radon tests, nearly half of Utah homes test above the World Health Organization's recommended mitigation threshold of 2.7 pCi/L. Some Utah cities, including Beaver, Wellsville and parts of Wasatch County regularly produce test results more than three times the WHO threshold.

Yet only an estimated 18% of American homes have ever been tested. Most families have no idea what their radon level is.

What families can do

The good news: radon is one of the most preventable environmental cancer risks. A radon test takes about three days of passive measurement and shows whether a home increases the cancer risk for everyone who lives there.

For families in the highest risk zones, mitigation systems, typically installed in a single day, can reduce indoor radon by up to 99%.

Given what the research now shows about radon's reach beyond the lungs, testing is a simple step any Utah family can take this year.

UtahRadon.org, a 501(c)(4) nonprofit, provides one free test kit per household at utahradon.org/cancer-research. The kit, shipping, and certified lab analysis are all free.