U of C researchers look at home radon exposure before, during and after pandemic

Cancer researchers at the University of Calgary are asking Canadians to measure how much time they are spending at home before, during and eventually after the pandemic to see whether their exposure to radon — the second leading cause of lung cancer in Canada — has increased.

The survey is limited to participants in an ongoing national Evict Radon study, led by the University of Calgary in partnership with Health Canada.

It's meant to raise awareness about the presence of the naturally occurring radioactive gas, measure it and teach people how to mitigate high levels.

But because people can still sign up for the Evict Radon study, they would then be eligible to participate in the current pandemic-related survey.

So far, nearly 20,000 online surveys have been delivered, mostly in Alberta. 

"What we're doing is one of the largest COVID-related analyses of shifting radon exposure, so we launched it on Tuesday [and] it's going strong," said Aaron Goodarzi, associate professor in the department of biochemistry and molecular biology at the University of Calgary.

Goodarzi said the trend toward working from home has been slowly increasing over the past several years.

But those numbers spiked when the pandemic hit, prompting him and his colleagues to look at the impact of this change, as well the demographics, occupations and locations in this shift. He said this will influence scientists' ability to estimate long-term radon-induced lung cancer burdens for Canada.

Radon is a radioactive gas naturally emitted from the earth through the breakdown of uranium in soil. It enters homes by seeping in through cracks, pipes, windows and foundations.

Radon exposure is the leading cause of lung cancer in non-smokers and it's estimated that in Canada there are more than 3,300 lung cancer deaths related to radon each year.

"And what we don't want is to underestimate or even overestimate those burdens with poor information," said Goodarzi.

Early results

Prior to launching the survey, approved by the University of Calgary's conjoint health research ethics board, Goodarzi and his team conducted a preliminary study involving 100 homes.

He said the results showed that the pandemic, thus far, has led to a 35 per cent increase in the annual residential radon exposure for that test group.

"Whether the 35 per cent increase remains true remains to be seen, but so far, yeah, it looks like a one-third increase in our net radon exposure, which is substantial," said Goodarzi.

Goodarzi said radon exposure is more concerning if it's happening over many years, not a few months. Children and young people are more at risk.

The Canadian guideline for radon in indoor air is 200 becquerels per cubic metre (200 Bq/m3).

Goodarzi said they've clocked levels as high as 11,000 Bcq in Regina.

"And if you're in that house and working from home, you need to know about it and do something about it," said Goodarzi.

Serious but fixable

Goodarzi said radon is serious but fixable. 

For example, he said people can install a sub-slab depressurization, wherein a little hole is drilled through the foundation into the soil underneath. An airtight fan then vents the radon up and outside.

Chelsea Montgomery is a participant in both the Evict Radon study and the pandemic-related survey.

She had her home in southwest Calgary tested in 2018. She said her home's radon levels were about twice the Canadian guideline, so she installed a sub-slab depressurization in 2019. She said her levels quickly dropped to well below the guidelines.

When the pandemic hit, she started working full-time from her home and has continued to since.

"I am so happy that we tested and had the opportunity … to remediate, because had we not known, we wouldn't have known otherwise, until potentially it's too late," she said.

Montgomery said it's not just work — because of travel and social restrictions, everyone is spending more time at home.

"Now, more than ever … it's important that people are testing and understanding what their levels are in their home."

Of the nearly 20,000 surveys sent out this week, Goodarzi said they've already received 1,700 back. 

"So we hope that everyone else will take that seven minutes or so to respond to us. And it will be an extremely statistical, powerful study," he said.

He expects initial results to be released sometime in 2021.