Millions of Canadian homes have high levels of cancer-causing radon. Is yours one of them? – CBC

Recent building code update mandates radon mitigation in new houses, but many existing homes still at risk

Jan 28, 2026

You can’t see or smell radon, the cancer-causing gas lurking inside millions of Canadian homes.

Roughly one in five residential buildings in Canada has high radon levels — a figure that’s more than doubled since the late 2000s — while radon-induced lung cancer kills an estimated 3,200 people each year, federal figures show.

This radioactive gas is released from the ground and flows into buildings across the country, but scientists say modern designs and renovations likely play a role in why more Canadians are being exposed in their own homes.

“We are pretty good at keeping air inside of our homes because we want to keep the heat inside … especially in this kind of cold climate that we live in,” said Pawel Mekarski, head of radon technical operations at Health Canada.

Read more: https://www.cbc.ca/news/health/radon-home-mitigation-9.7063662