Growing number of Canadian households contain dangerous levels of radon gas

Radioactive radon exposure in Canada is rising and continues to be a critical public health concern, according to the 2024 Cross-Canada Survey of Radon Exposure in the Residential Buildings of Urban and Rural Communities.

There are an estimated 10.3 million Canadians living in houses with high radon, increasing their risk of developing lung cancer in the future. The report reveals nearly 18 per cent of Canadian homes contain radon levels at or above 200 Bq/m³, the threshold at which Health Canada advises action to reduce indoor radon levels. This is more than double the seven per cent of households that were estimated to have radon levels at or above this limit in 2012.

Led by Dr. Aaron Goodarzi, the national report defines radon exposure by specific regions, urban to rural communities, and building design types. Radon is a colourless, odourless and radioactive gas that is the second largest contributor to cancer worldwide.

"The new Cross Canada Radon Survey provides a greater understanding of how people living in Canada in the 2020s are being exposured to radon across our diverse communities, houses and regions," says Goodarzi. "Alarmingly, this report concludes that Canadians are among the most highly radon-exposed people on Earth, and that means we urgently need to address this to avoid a future of prevalent, but otherwise avoidable lung cancers."