Experts Urge Radon Testing and Home Mitigation to Cut Lung Cancer Risk

Health professionals and researchers are urging more Canadians to test for radon gas in their homes and, where levels are high, take measures to mitigate exposure — actions they say can reduce the risk of developing lung cancer. Radon is an invisible, odourless radioactive gas that occurs naturally as uranium decays in soil and rock. When it enters buildings and accumulates, especially in basements and lower levels, prolonged exposure increases the likelihood of lung cancer, particularly among non-smokers.

According to public health authorities, radon is one of the most significant environmental causes of lung cancer in Canada. It contributes to thousands of deaths annually, with both smokers and non-smokers at risk — though the risk is highest for people who also smoke. Despite this, many Canadians remain unaware of radon and how to test for it, and fewer still have taken steps to measure or mitigate concentrations in their homes.

Testing for radon is relatively straightforward and inexpensive: homeowners can purchase or rent radon detectors and place them in their main living areas or basements for a long-term measurement (typically over several months) to obtain reliable results. If the measured levels exceed established health guidelines, specialists can install mitigation systems — such as sub-slab depressurization or improved ventilation — to reduce indoor concentrations.

Experts emphasise that no level of radon exposure is completely safe, and even levels below the national guideline carry some risk. However, lowering radon concentrations in homes with high levels can substantially reduce associated lung cancer risk over time. Some public health advocates are calling for greater public awareness campaigns, incentives for testing and remediation, and integration of radon considerations into building codes to protect residents more broadly.

Radon levels can vary widely between neighbouring homes, depending on soil composition, foundation type and ventilation, making individual testing essential for every household. Given that radon is most prevalent in colder months when homes are sealed against the cold, testing during winter can reveal worst-case exposure scenarios.

Authorities recommend that Canadians, particularly those in regions with historically elevated radon, consider long-term testing and act on results. While mitigation can represent an upfront cost, many experts argue it is a cost-effective public health intervention when viewed in terms of lives saved and future cancer burden reduced.