A countrywide study says radioactive radon exposure is on the rise and continues to be a critical public health concern.

The report, released Wednesday, is the first update on radon exposure in Canada since 2012.

B次元官网网址淲eB次元官网网址檙e more than a dozen years out from understanding how the Canadian residential radon problem has changed, and indeed it has changed,B次元官网网址� said the scientific lead on the report, Aaron Goodarzi, a professor of biochemistry and molecular biology at the University of CalgaryB次元官网网址檚 Cumming School of Medicine.

Radon is a colourless, odourless, radioactive gas that forms naturally when uranium, thorium or radium B次元官网网址� radioactive metals B次元官网网址� break down in rocks, soil and groundwater. Exposure comes from breathing radon in air that comes through cracks and gaps in buildings and homes.

ItB次元官网网址檚 the second-leading cause of lung cancer in Canadians, especially for those who donB次元官网网址檛 smoke.

Goodarzi said that in 2012, about seven per cent of homes in Canada were found to have above Health CanadaB次元官网网址檚 safe level of radon B次元官网网址� 200 becquerels per cubic metre.

In 2024, 75,000 readings were taken from urban and rural residential buildings across Canada. Data from the 2021 census was also used.

B次元官网网址淭his is now 17.8 per cent, so thatB次元官网网址檚 up more than double, 2 1/2 times greater, in terms of a property exceeding CanadaB次元官网网址檚 guideline,B次元官网网址� he said.

B次元官网网址淔rom my perspective as a researcher studying this over the past 10 years, itB次元官网网址檚 no surprise. As a lung cancer prevention advocate, of course it is alarming.B次元官网网址�

Goodarzi said there are an estimated 10.3 million Canadians living in houses with high radon, increasing their risk of developing lung cancer.

The study says one in five Canadian residential buildings are at or above Health CanadaB次元官网网址檚 safe level.

In Atlantic Canada, the B.C. Interior and Yukon, itB次元官网网址檚 one in three.

B次元官网网址淭hereB次元官网网址檚 no area in Canada that is risk-free,B次元官网网址� Goodarzi said. B次元官网网址淐anada is amongst the highest that has been mapped globally in the world.B次元官网网址�

Goodarzi said the rise in radon could be partially because readings were taken on a ground floor or in a basement compared to the rest of a home. He said new home builds are also more energy efficient and trap radon inside.

He said the new report also contains five times more readings than the 14,000 taken in 2012.

Goodarzi said people need to install radon detectors in their homes and take measures to remove high levels of the gas. He said he also hopes changes will be made in the construction of new homes to account for radon.

A coalition of researchers behind the report also includes scientists from Health Canada and CAREX Canada.

Alison Wallace, a thoracic surgeon at the QEII Health Sciences Centre in Halifax, is a co-author.

B次元官网网址淚B次元官网网址檓 very concerned. I think the data accuracy of the new report is more robust,B次元官网网址� she said.

B次元官网网址淚tB次元官网网址檚 more real numbers and people should take it seriously.B次元官网网址�