Increased cancer risk from radon in schools is low, health official says
Joel Krahn/Yukon News
Yukon’s deputy chief medical officer of health says students in schools with unacceptable levels of radon do not have a substantially increased risk of developing lung cancer.
Earlier this month, an auditor general’s report revealed that the Yukon government failed to monitor four schools — Jack Hulland Elementary, Holy Family Elementary and the Teen Parent Centre in Whitehorse and Nelnah Bessie John School in Beaver Creek — after they were found to have elevated radon levels in 2008.
Radon is a colourless, odourless gas that occurs naturally in certain kinds of soil, but can seep up into buildings and become more concentrated. It is the second-leading cause of lung cancer after smoking, but it is not linked to any other disease.
The Department of Education is now monitoring radon in all Yukon schools, and will have results this spring. But early data suggests that all four original schools still have high radon levels. Remediation has been completed at Jack Hulland and ordered for the other three.
Still, the radon levels in the four schools won’t have a huge impact on students’ risk of developing lung cancer, according to Dr. Catherine Elliott.
“The absolute risk increase that occurred from exposure in schools is small,” she said.
That’s because radon is only dangerous if people are exposed to elevated levels over many years.
Health Canada guidelines state that radon levels above 200 becquerels per cubic metre are unacceptable. In 2008, the highest readings from the four schools in question were above that threshold, but lower than 400 becquerels per cubic metre.
Elliott explained that the risk of developing lung cancer increases from one in 100 to one in 50 for people exposed to 200 becquerels per cubic metre of radon over a lifetime — every hour of every day for 70 years.
But even if someone were exposed to 450 becquerels per cubic metre around the clock for 10 years, their risk would only increase from one per cent to 1.1 per cent, she said.
And even that, she said, is “way more than any child would have been exposed to in the schools.”
Still, she said, the schools are working to bring radon levels below the Health Canada guideline, recognizing that radon exposure can build up over a lifetime.
Elliott said parents “should be concerned about radon exposure if they live in Yukon.” The territory has the third-highest percentage of homes that exceed the radon guideline in Canada.
“Concerned parents should take this as a motivator to also test their homes… where the most exposure occurs,” she said. She also recommended that people quit smoking. The rate of lung cancer increases to one in six for those who smoke and who are exposed to radon over a lifetime.
Yukon Lung Association president Doug MacLean told the News that Yukon Housing still has a limited number of radon test kits available for homeowners, and that kits can also be purchased at Home Hardware.
He said the association hopes to offer free radon test kits in November as part of Radon Awareness Month.