Maps can encourage home radon testing in the right settings

(Press-News.org) Risk maps for the cancer-causing gas radon can encourage people to test their homes for the substance, but only if homeowners live in known, higher-risk areas, new University of Oregon research finds.

For those living in low-risk areas, maps seem to not affect, or may even decrease, people’s intent to test for radon.

“It might be the case that a household is exposed to radon for many, many years and they don't actually know about it, especially if they're not testing for radon,” said Cathy Slavik, the study’s lead author, who did the work as a Banting Postdoctoral Fellow at the UO. “That exposure can become really problematic,” regardless of the risk level in the area.

Slavik and her colleagues published their findings Dec. 19 in the journal Public Health.

Radon exposure is the second-leading cause of lung cancer after smoking. But it’s an “invisible risk,” said Slavik, now an assistant professor at Simon Fraser University in British Columbia, Canada, and a researcher at Legacy for Airway Health.

The radioactive gas is odorless, colorless and tasteless, and thus can lurk in homes without occupants knowing.

Radon forms when uranium, which occurs naturally in most soil, decays over time. As it rises in the air, it can enter buildings through cracks in the foundation. Certain geographic areas are at higher risk due to the uranium content of the bedrock and soil.

But any home can accumulate radon, even if it is newer or well-sealed. The gas is also relatively simple to mitigate, if people know it’s there.

As a public health communicator, Slavik was interested in how to raise awareness about something posing a significant risk but that relatively few people know about. She discovered that British Columbia had ample data about residential radon exposure risk and decided to zero in on the province as her study area.

Slavik and her colleagues collaborated with researchers at the British Columbia Centre for Disease Control to design nine radon exposure risk maps. Each map had a slightly different way of presenting radon risk levels.

For example, one simply stated low, medium or high risk, while another listed the average radon concentrations of homes in an area. The team’s aim was to determine if a map’s features influenced whether a reader would be likely to test for radon.

The team disseminated the maps through an online survey to 2,000 participants in British Columbia. Each person answered questions about their radon knowledge and testing experience, then viewed a randomly assigned map.

Another factor the study considered was smoking status. People who smoke are at higher risk from lung cancer already, and that risk compounds when exposed to radon. After looking at the map, participants reported their radon testing intentions.

“The type of map didn't matter so much as just seeing the map,” Slavik said.

In medium-high- and high-risk areas, seeing the map significantly increased participants' testing intentions, regardless of which map they saw or whether they smoked. In low-to-medium-risk areas, however, the maps didn’t seem to make a difference in testing intentions. And in the lowest-risk areas, testing intentions of nonsmokers even decreased slightly.

One reason for the divide might be that people interpret low-risk as meaning they don’t need to take action, suggests Ellen Peters, director of the Center for Science Communication Research at the UO, Philip H. Knight Chair, and a professor of both psychology and communications.

“Those low-risk people, and particularly nonsmokers who are at even lower risk, they found meaning in the maps that was unintended,” she said.

Communicators need to think about both intended and unintended takeaways from their messaging, she said.

Maps might not be a catch-all solution to raising awareness about radon risk levels, and perhaps different approaches should be used to target areas depending on their risk level, Slavik said.

She’s eager to test the same framework with other environmental risks, particularly wildfire smoke. The challenges of risk awareness from wildfire smoke overlap with those of radon, she said, in that air quality can be poor even when smoke isn’t visible or detectable by smell. And, also like radon, even low levels of smoke can carry health risks.

“At the end of the day, we know we can’t sway everyone,” Slavik said. “But if maps can encourage at least some people to take action on radon, that incremental increase in risk reduction is still meaningful.”

— By Jude Coleman

This research was funded by the Canadian Institutes of Health Research through the Banting Postdoctoral Fellowship, the University of Oregon's Center for Science Communication Research, the U.S. National Science Foundation, and the Herbert Kariel Fund.

About the University of Oregon School of Journalism and Communication  
Founded in 1916, the University of Oregon School of Journalism and Communication is a national leader in scholarship and education in the fields of advertising, journalism, media studies, public relations and strategic communication. The school offers doctoral, master’s and undergraduate degree programs that challenge students to become ethical communicators, critical thinkers, productive scholars and responsible citizens in a global society. The School of Journalism and Communication’s award-winning faculty contribute innovative research and professional projects that lead the field in an evolving media landscape.

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