A comprehensive, Canada-wide study found that Canada has some of the highest levels of radon in homes in the world. Roughly half the homes tested failed to meet WHO standards, and even by Canada's more lenient standards, one in five were above the threshold of what's considered safe. The prairie provinces scored worst in the country—but no region was immune.

Long-term impacts of radon exposure can lead to lung cancer—in fact it's the second biggest cause of lung cancer behind smoking. So why don't more Canadians know of this danger? Which homes are most vulnerable to high levels of radon? How can you easily test for it, and what can you do if your home is unsafe? As one researcher says, "This is an avoidable public health crisis."

To learn more about radon exposure visit evictradon.org.

GUEST: Declan Keogh, Investigative Journalism Bureau (You can read the project by the IJB and the Toronto Star right here)

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