• Posted February 28, 2024

Radon a Bigger Threat to Rural Homes

Rural homeowners face a greater threat from odorless, radioactive radon gas than people living in urban areas, and it's likely due to the wells they rely on for their water supply, a new study shows.

On average, people living in rural communities are exposed to 30% higher residential radon levels than people in cities and suburbs, researchers found.

This radon appears to be seeping into homes because of deep wells dug on the property for water, according to results published Feb. 26 in the journal Scientific Reports.

“It's the water wells,” said senior researcher Aaron Goodarzi, an associate professor with the University of Calgary in Canada. “Not the water, but the wells themselves, appear to be acting as unintended straws for radon gas deep in the ground.”

“Thankfully, lowering radon levels in a home is fixable,” Goodarzi added.

Radon is an invisible, tasteless gas naturally released by decaying radioactive elements in rocks, soil and water, according to the U.S. Centers for Disease Control and Prevention.

Radon causes an estimated 21,000 lung cancer deaths in the United States each year, and it is the second leading cause of lung cancer deaths after cigarette smoke, the CDC says.

For the study, researchers analyzed more than 42,000 Canadian residential properties in more than 2,000 distinct communities.

They assessed radon levels in the homes, as well as the geology of the property, the style of the home and unique features on or near the house.

They found that rural residents are exposed to higher radon levels, on average, and that the majority of the effect is attributed to proximity to groundwater wells. 

Researchers tested well water for radon and found there wasn't enough to significantly contribute to high radon in indoor air.

Instead, the radon appears to be seeping up from the drill hole space around the pipes that bring well water into the rural homes, researchers said.

“We know that methane gas bubbles up around the outside of some oil and gas wells,” said co-lead researcher Cathy Ryan, a professor at the University of Calgary in Canada. “This caused us to wonder if 'unintended' or 'fugitive' radon gas migration might also be occurring along water wells.”

The higher rural radon effect was consistent in homes across Canada, researchers said.

The results underscore the importance of regular radon testing, particularly in rural homes that rely on well water, they added.

High radon levels in indoor air can be addressed through a radon reduction system, the CDC says. Vent pipes can be installed to pull radon from beneath the house and expel it outdoors.

These findings also should be taken into account when designing future homes, they added.

“In order to design safe and healthy buildings, it's imperative to understand the environment in which they exist,” said co-lead researcher Josh Taron, associate dean of research and innovation at the University of Calgary's School of Architecture, Planning and Landscape.

“While soil gas has often been overlooked in North American homes, this work gives us important insights into the geological issues that building designs must be able to safely address,” Taron added in a university news release.

The study received funding by the Alberta Real Estate Foundation.

More information

The U.S. Centers for Disease Control and Prevention has more about radon.

SOURCE: University of Calgary, news release, Feb. 26, 2024